Bellera, Carine; Proust-Lima, Cécile; Joseph, Lawrence; Richaud, Pierre; Taylor, Jeremy; Sandler, Howard; Hanley, James; Mathoulin-Pélissier, Simone
2018-04-01
Background Biomarker series can indicate disease progression and predict clinical endpoints. When a treatment is prescribed depending on the biomarker, confounding by indication might be introduced if the treatment modifies the marker profile and risk of failure. Objective Our aim was to highlight the flexibility of a two-stage model fitted within a Bayesian Markov Chain Monte Carlo framework. For this purpose, we monitored the prostate-specific antigens in prostate cancer patients treated with external beam radiation therapy. In the presence of rising prostate-specific antigens after external beam radiation therapy, salvage hormone therapy can be prescribed to reduce both the prostate-specific antigens concentration and the risk of clinical failure, an illustration of confounding by indication. We focused on the assessment of the prognostic value of hormone therapy and prostate-specific antigens trajectory on the risk of failure. Methods We used a two-stage model within a Bayesian framework to assess the role of the prostate-specific antigens profile on clinical failure while accounting for a secondary treatment prescribed by indication. We modeled prostate-specific antigens using a hierarchical piecewise linear trajectory with a random changepoint. Residual prostate-specific antigens variability was expressed as a function of prostate-specific antigens concentration. Covariates in the survival model included hormone therapy, baseline characteristics, and individual predictions of the prostate-specific antigens nadir and timing and prostate-specific antigens slopes before and after the nadir as provided by the longitudinal process. Results We showed positive associations between an increased prostate-specific antigens nadir, an earlier changepoint and a steeper post-nadir slope with an increased risk of failure. Importantly, we highlighted a significant benefit of hormone therapy, an effect that was not observed when the prostate-specific antigens trajectory was not accounted for in the survival model. Conclusion Our modeling strategy was particularly flexible and accounted for multiple complex features of longitudinal and survival data, including the presence of a random changepoint and a time-dependent covariate.
Continuous monitoring of prostate position using stereoscopic and monoscopic kV image guidance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stevens, M. Tynan R.; Parsons, Dave D.; Robar, James L.
2016-05-15
Purpose: To demonstrate continuous kV x-ray monitoring of prostate motion using both stereoscopic and monoscopic localizations, assess the spatial accuracy of these techniques, and evaluate the dose delivered from the added image guidance. Methods: The authors implemented both stereoscopic and monoscopic fiducial localizations using a room-mounted dual oblique x-ray system. Recently developed monoscopic 3D position estimation techniques potentially overcome the issue of treatment head interference with stereoscopic imaging at certain gantry angles. To demonstrate continuous position monitoring, a gold fiducial marker was placed in an anthropomorphic phantom and placed on the Linac couch. The couch was used as a programmablemore » translation stage. The couch was programmed with a series of patient prostate motion trajectories exemplifying five distinct categories: stable prostate, slow drift, persistent excursion, transient excursion, and high frequency excursions. The phantom and fiducial were imaged using 140 kVp, 0.63 mAs per image at 1 Hz for a 60 s monitoring period. Both stereoscopic and monoscopic 3D localization accuracies were assessed by comparison to the ground-truth obtained from the Linac log file. Imaging dose was also assessed, using optically stimulated luminescence dosimeter inserts in the phantom. Results: Stereoscopic localization accuracy varied between 0.13 ± 0.05 and 0.33 ± 0.30 mm, depending on the motion trajectory. Monoscopic localization accuracy varied from 0.2 ± 0.1 to 1.1 ± 0.7 mm. The largest localization errors were typically observed in the left–right direction. There were significant differences in accuracy between the two monoscopic views, but which view was better varied from trajectory to trajectory. The imaging dose was measured to be between 2 and 15 μGy/mAs, depending on location in the phantom. Conclusions: The authors have demonstrated the first use of monoscopic localization for a room-mounted dual x-ray system. Three-dimensional position estimation from monoscopic imaging permits continuous, uninterrupted intrafraction motion monitoring even in the presence of gantry rotation, which may block kV sources or imagers. This potentially allows for more accurate treatment delivery, by ensuring that the prostate does not deviate substantially from the initial setup position.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ng, Jin Aun; Institute of Medical Physics, School of Physics, University of Sydney, New South Wales; Booth, Jeremy T.
2012-12-01
Purpose: Most linear accelerators purchased today are equipped with a gantry-mounted kilovoltage X-ray imager which is typically used for patient imaging prior to therapy. A novel application of the X-ray system is kilovoltage intrafraction monitoring (KIM), in which the 3-dimensional (3D) tumor position is determined during treatment. In this paper, we report on the first use of KIM in a prospective clinical study of prostate cancer patients undergoing intensity modulated arc therapy (IMAT). Methods and Materials: Ten prostate cancer patients with implanted fiducial markers undergoing conventionally fractionated IMAT (RapidArc) were enrolled in an ethics-approved study of KIM. KIM involves acquiringmore » kV images as the gantry rotates around the patient during treatment. Post-treatment, markers in these images were segmented to obtain 2D positions. From the 2D positions, a maximum likelihood estimation of a probability density function was used to obtain 3D prostate trajectories. The trajectories were analyzed to determine the motion type and the percentage of time the prostate was displaced {>=}3, 5, 7, and 10 mm. Independent verification of KIM positional accuracy was performed using kV/MV triangulation. Results: KIM was performed for 268 fractions. Various prostate trajectories were observed (ie, continuous target drift, transient excursion, stable target position, persistent excursion, high-frequency excursions, and erratic behavior). For all patients, 3D displacements of {>=}3, 5, 7, and 10 mm were observed 5.6%, 2.2%, 0.7% and 0.4% of the time, respectively. The average systematic accuracy of KIM was measured at 0.46 mm. Conclusions: KIM for prostate IMAT was successfully implemented clinically for the first time. Key advantages of this method are (1) submillimeter accuracy, (2) widespread applicability, and (3) a low barrier to clinical implementation. A disadvantage is that KIM delivers additional imaging dose to the patient.« less
Farris, Megan S; Kopciuk, Karen A; Courneya, Kerry S; McGregor, S Elizabeth; Wang, Qinggang; Friedenreich, Christine M
2017-04-01
The aim of our study was to identify physical and mental health-related quality of life (HRQoL) trajectories after a prostate cancer diagnosis and systematically characterize trajectories by behaviours and prognostic factors. Prostate cancer survivors (n = 817) diagnosed between 1997 and 2000 were recruited between 2000 and 2002 into a prospective repeated measurements study. Behavioural/prognostic data were collected through in-person interviews and questionnaires. HRQoL was collected at three post-diagnosis time-points, approximately 2 years apart using the Short Form (SF)-36 validated questionnaire. To identify physical and mental HRQoL trajectories, group-based trajectory modelling was undertaken. Differences between groups were evaluated by assessing influential dropouts (mortality/poor health), behavioural/prognostic factors at diagnosis or during the follow-up. Three trajectories of physical HRQoL were identified including: average-maintaining HRQoL (32.2%), low-declining HRQoL (40.5%) and very low-maintaining HRQoL (27.3%). In addition, three trajectories for mental HRQoL were identified: average-increasing HRQoL (66.5%), above average-declining HRQoL (19.7%) and low-increasing HRQoL (13.8%). In both physical and mental HRQoL, dropout from mortality/poor health differed between trajectories, thus confirming HRQoL and mortality were related. Furthermore, increased Charlson comorbidity index score was consistently associated with physical and mental HRQoL group membership relative to average maintaining groups, while behaviours such as time-varying physical activity was associated with physical HRQoL trajectories but not mental HRQoL trajectories. It was possible to define three trajectories of physical and mental HRQoL after prostate cancer. These data provide insights regarding means for identifying subgroups of prostate cancer survivors with lower or declining HRQoL after diagnosis whom could be targeted for interventions aimed at improving HRQoL. © 2016 UICC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riofrio, D; Luan, S; Zhou, J
Purpose: In prostate HDR brachytherapy, interstitial implants are placed manually on the fly. The aim for this research is to develop a computer algorithm to find optimal and reliable implant trajectories using minimal number of implants. Methods: Our new algorithm mainly uses these key ideas: (1) positive charged static particles are uniformly placed on the surface of prostate and critical structures such as urethra, bladder, and rectum. (2) Positive charged kinetic particles are placed at a cross-section of the prostate with an initial velocity parallel to the principal implant direction. (3) The kinetic particles move through the prostate, interacting withmore » each other, spreading out, while staying away from the prostate surface and critical structures. The initial velocity ensures that the trajectories observe the curvature constraints of typical implant procedures. (4) The finial trajectories of kinetic particles are smoothed using a third-degree polynomial regression, which become the implant trajectories. (5) The dwelling times and final dose distribution are calculated using least-distance programming. Results: (1) We experimented with previously treated cases. Our plan achieves all prescription goals while reducing the number of implants by 41%! Our plan also has less uniform target dose, which implies a higher dose is delivered to the prostate. (2) We expect future implant procedures will be performed under the guidance of such pre-calculated trajectories. To assess the applicability, we randomly perturb the tracks to mimic the manual implant errors. Our studies showed the impact of these perturbations are negligible, which is compensated by the least distance programming. Conclusions: We developed a new inverse planning system for prostate HDR therapy that can find optimal implant trajectories while minimizing the number of implants. For future work, we plan to integrate our new inverse planning system with an existing needle tracking system.« less
Chambers, Suzanne K; Ng, Shu Kay; Baade, Peter; Aitken, Joanne F; Hyde, Melissa K; Wittert, Gary; Frydenberg, Mark; Dunn, Jeff
2017-10-01
To describe trajectories of health-related quality of life (QoL), life satisfaction, and psychological adjustment for men with prostate cancer over the medium to long term and identify predictors of poorer outcomes using growth mixture models. One-thousand sixty-four (82.4% response) men diagnosed with prostate cancer were recruited close to diagnosis and assessed over a 72-month (6-year) period with self-report assessment of health-related QoL, life satisfaction, cancer-related distress, and prostate specific antigen anxiety. Urinary, bowel, and sexual function were also assessed using validated questionnaires. Poorer physical QOL was predicted by older age, lower education, lower income, comorbidities, and receiving hormone therapy. Lower life satisfaction was related to younger age, lower income, not being partnered, and comorbidities. Poorer psychological trajectories were predicted by younger age, lower income, comorbidities, and receiving radical prostatectomy or brachytherapy. Better urinary, bowel, and sexual function were related to better global outcomes over time. Anxiety about prostate specific antigen testing was rare. Distinct trajectories exist for medium- to long-term QoL, life satisfaction, and psychological adjustment after prostate cancer; with age and socioeconomic deprivation playing a differential role in men's survivorship profile and the impact of functional status on outcomes increasing over time. These results reinforce the need for an appraisal of men's life course in addition to treatment side effects when planning survivorship care after cancer. © 2016 The Authors. Psycho-Oncology Published by John Wiley & Sons Ltd.
Trajectory optimization for dynamic couch rotation during volumetric modulated arc radiotherapy
NASA Astrophysics Data System (ADS)
Smyth, Gregory; Bamber, Jeffrey C.; Evans, Philip M.; Bedford, James L.
2013-11-01
Non-coplanar radiation beams are often used in three-dimensional conformal and intensity modulated radiotherapy to reduce dose to organs at risk (OAR) by geometric avoidance. In volumetric modulated arc radiotherapy (VMAT) non-coplanar geometries are generally achieved by applying patient couch rotations to single or multiple full or partial arcs. This paper presents a trajectory optimization method for a non-coplanar technique, dynamic couch rotation during VMAT (DCR-VMAT), which combines ray tracing with a graph search algorithm. Four clinical test cases (partial breast, brain, prostate only, and prostate and pelvic nodes) were used to evaluate the potential OAR sparing for trajectory-optimized DCR-VMAT plans, compared with standard coplanar VMAT. In each case, ray tracing was performed and a cost map reflecting the number of OAR voxels intersected for each potential source position was generated. The least-cost path through the cost map, corresponding to an optimal DCR-VMAT trajectory, was determined using Dijkstra’s algorithm. Results show that trajectory optimization can reduce dose to specified OARs for plans otherwise comparable to conventional coplanar VMAT techniques. For the partial breast case, the mean heart dose was reduced by 53%. In the brain case, the maximum lens doses were reduced by 61% (left) and 77% (right) and the globes by 37% (left) and 40% (right). Bowel mean dose was reduced by 15% in the prostate only case. For the prostate and pelvic nodes case, the bowel V50 Gy and V60 Gy were reduced by 9% and 45% respectively. Future work will involve further development of the algorithm and assessment of its performance over a larger number of cases in site-specific cohorts.
Marshall, Lynn M.; Holton, Kathleen F.; Parsons, J. Kellogg; Lapidus, Jodi A.; Ramsey, Katrina; Barrett-Connor, Elizabeth
2014-01-01
Background Knowledge of factors associated with the course of lower urinary tract symptoms (LUTS) before treatment is needed to inform preventive interventions. In a prospective study of elderly men untreated for LUTS, we identified factors associated with symptom progression and remission. Methods In community dwelling U.S. men age ≥ 65 years, the American Urological Association Symptom Index (AUA-SI) was repeated four times, once at baseline (2000–2002) and then every two years thereafter. Analyses included 1740 men with all four AUA-SI assessments, who remained free from diagnosed prostate cancer, and who reported no treatment for LUTS or benign prostatic hyperplasia (BPH) during follow-up that averaged 6.9 (±0.4) years. LUTS change was determined with group-based trajectory modeling of the repeated AUA-SI measures. Multivariable logistic regression was then used to determine the baseline factors associated with progressing compared to stable trajectories, and with remitting compared to progressing trajectories. Lifestyle, body mass index (BMI) (kg/m2), mobility, mental health (Short-Form 12), medical history, and prescription medications were considered for selection. Odds ratios (OR) and 95% confidence intervals (CI) were estimated for variables in each model. Results We identified 10 AUA-SI trajectories: four stable (1 277 men, 73%), three progressing (345 men, 20%), two remitting (98 men, 6%), and one mixed (20 men, 1%). Men in progressing compared to stable trajectories were more likely to have mobility limitations (OR=2.0, 95% CI: 1.0–3.8), poor mental health (OR=1.9, 95% CI: 1.1–3.4), BMI ≥ 25.0 kg/m2 (OR=1.7, 95% CI: 1.0–2.8), hypertension (OR=1.5, 95% CI: 1.0–2.4), and back pain (OR=1.5, 95% CI: 1.0–2.4). Men in remitting compared to progressing trajectories more often used central nervous system medications (OR=2.3, 95% CI: 1.1–4.9) and less often had a history of problem drinking (OR=0.4. 95% CI: 0.2–0.9). Conclusions Several non-urological lifestyle and health factors were independently associated with risk of LUTS progression in older men. PMID:25000909
TH-A-9A-10: Prostate SBRT Delivery with Flattening-Filter-Free Mode: Benefit and Accuracy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, T; Yuan, L; Sheng, Y
Purpose: Flattening-filter-free (FFF) beam mode offered on TrueBeam™ linac enables delivering IMRT at 2400 MU/min dose rate. This study investigates the benefit and delivery accuracy of using high dose rate in the context of prostate SBRT. Methods: 8 prostate SBRT patients were retrospectively studied. In 5 cases treated with 600-MU/min dose rate, continuous prostate motion data acquired during radiation-beam-on was used to analyze motion range. In addition, the initial 1/3 of prostate motion trajectories during each radiation-beam-on was separated to simulate motion range if 2400-MU/min were used. To analyze delivery accuracy in FFF mode, MLC trajectory log files from anmore » additional 3 cases treated at 2400-MU/min were acquired. These log files record MLC expected and actual positions every 20ms, and therefore can be used to reveal delivery accuracy. Results: (1) Benefit. On average treatment at 600-MU/min takes 30s per beam; whereas 2400-MU/min requires only 11s. When shortening delivery time to ~1/3, the prostate motion range was significantly smaller (p<0.001). Largest motion reduction occurred in Sup-Inf direction, from [−3.3mm, 2.1mm] to [−1.7mm, 1.7mm], followed by reduction from [−2.1mm, 2.4mm] to [−1.0mm, 2.4mm] in Ant-Pos direction. No change observed in LR direction [−0.8mm, 0.6mm]. The combined motion amplitude (vector norm) confirms that average motion and ranges are significantly smaller when beam-on was limited to the 1st 1/3 of actual delivery time. (2) Accuracy. Trajectory log file analysis showed excellent delivery accuracy with at 2400 MU/min. Most leaf deviations during beam-on were within 0.07mm (99-percentile). Maximum leaf-opening deviations during each beam-on were all under 0.1mm for all leaves. Dose-rate was maintained at 2400-MU/min during beam-on without dipping. Conclusion: Delivery prostate SBRT with 2400 MU/min is both beneficial and accurate. High dose rates significantly reduced both treatment time and intra-beam prostate motion range. Excellent delivery accuracy was confirmed with very small leaf motion deviation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheng, L; Duke University Medical Center, Durham, NC; Fudan University Shanghai Cancer Center, Shanghai
Purpose: To investigate prostate imaging onboard radiation therapy machines using a novel robotic, 49-pinhole Single Photon Emission Computed Tomography (SPECT) system. Methods: Computer-simulation studies were performed for region-of-interest (ROI) imaging using a 49-pinhole SPECT collimator and for broad cross-section imaging using a parallel-hole SPECT collimator. A male XCAT phantom was computersimulated in supine position with one 12mm-diameter tumor added in the prostate. A treatment couch was added to the phantom. Four-minute detector trajectories for imaging a 7cm-diameter-sphere ROI encompassing the tumor were investigated with different parameters, including pinhole focal length, pinhole diameter and trajectory starting angle. Pseudo-random Poisson noise wasmore » included in the simulated projection data, and SPECT images were reconstructed by OSEM with 4 subsets and up to 10 iterations. Images were evaluated by visual inspection, profiles, and Root-Mean- Square-Error (RMSE). Results: The tumor was well visualized above background by the 49-pinhole SPECT system with different pinhole parameters while it was not visible with parallel-hole SPECT imaging. Minimum RMSEs were 0.30 for 49-pinhole imaging and 0.41 for parallelhole imaging. For parallel-hole imaging, the detector trajectory from rightto- left yielded slightly lower RMSEs than that from posterior to anterior. For 49-pinhole imaging, near-minimum RMSEs were maintained over a broader range of OSEM iterations with a 5mm pinhole diameter and 21cm focal length versus a 2mm diameter pinhole and 18cm focal length. The detector with 21cm pinhole focal length had the shortest rotation radius averaged over the trajectory. Conclusion: On-board functional and molecular prostate imaging may be feasible in 4-minute scan times by robotic SPECT. A 49-pinhole SPECT system could improve such imaging as compared to broadcross-section parallel-hole collimated SPECT imaging. Multi-pinhole imaging can be improved by considering pinhole focal length, pinhole diameter, and trajectory starting angle. The project is supported by the NIH grant 5R21-CA156390.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ryu, Bon; Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario; Bax, Jeff
2012-08-01
Purpose: First, to show that low-dose-rate prostate brachytherapy plans using oblique needle trajectories are more successful than parallel trajectories for large prostates with pubic arch interference (PAI); second, to test the accuracy of delivering an oblique plan by using a three-dimensional (3D) transrectal ultrasonography (TRUS)-guided mechatronic system. Methods and Materials: Prostates were contoured for 5 subjects' 3D TRUS images showing a maximum PAI of {<=}1 cm and a prostate volume of <50 cc. Two planning studies were done. First, prostate contours were artificially enlarged to 45 to 80 cc in 5- to 10-cc increments for a single subject. Second, allmore » subject prostate contours were enlarged to 60 cc. For each study, three types of plans were manually created for comparison: a parallel needle template (PT) plan, a parallel needle no-template (PNT) plan, and an oblique needle no-template (OBL) plan. Needle positions and angles were not discretized for nontemplate plans. European Society for Therapeutic Radiology and Oncology dose-volume histogram guidelines, iodine-125 (145-Gy prescription, 0.43 U), and needle angles of <15 Degree-Sign were used. An OBL plan was delivered to a pubic arch containing a 60-cc prostate phantom that mimicked the anatomy of the subject with the greatest PAI (23% by volume). Results: In the increasing-prostate volume study, OBL plans were successful for prostates of {<=}80 cc, and PT plans were successful for prostates of <65 cc. In paired, one-sided t tests for the 60-cc volume study, OBL plans showed dosimetric improvements for all organs compared to both of the parallel type plans (p < 0.05); PNT plans showed a benefit only in planning target volumes receiving more than 100 Gy compared to PT plans. A computed tomography scan of the phantom showed submillimeter seed placement accuracy in all directions. Conclusion: OBL plans were significantly better than parallel plans, and an OBL plan was accurately delivered to a 60-cc prostate phantom with 23% PAI by volume.« less
Trajectory of body shape across the lifespan and cancer risk
Song, Mingyang; Willett, Walter C.; Hu, Frank B.; Spiegelman, Donna; Must, Aviva; Wu, Kana; Chan, Andrew T.; Giovannucci, Edward L.
2016-01-01
The influence of adiposity over life course on cancer risk remains poorly understood. We assessed trajectories of body shape from age 5 up to 60 using a group-based modeling approach among 73,581 women from the Nurses’ Health Study and 32,632 men from the Health Professionals Follow-up Study. After a median of approximately 10 years of follow-up, we compared incidence of total and obesity-related cancers (cancers of the esophagus [adenocarcinoma only], colorectum, pancreas, breast [after menopause], endometrium, ovaries, prostate [advanced only], kidney, liver and gallbladder) between these trajectories. We identified 5 distinct trajectories of body shape: lean-stable, lean-moderate increase, lean-marked increase, medium-stable, and heavy-stable/increase. Compared with women in the lean-stable trajectory, those in the lean-marked increase and heavy-stable/increase trajectories had a higher cancer risk in the colorectum, esophagus, pancreas, kidney, and endometrium (relative risk [RR] ranged from 1.22 to 2.56). Early life adiposity was inversely while late life adiposity was positively associated with postmenopausal breast cancer risk. In men, increased body fatness at any life period was associated with a higher risk of esophageal adenocarcinoma and colorectal cancer (RR ranged from 1.23 to 3.01), and the heavy-stable/increase trajectory was associated with a higher risk of pancreatic cancer, but lower risk of advanced prostate cancer. The trajectory-cancer associations were generally stronger for non-smokers and women who did not use menopausal hormone therapy. In conclusion, trajectories of body shape throughout life were related to cancer risk with varied patterns by sex and organ, indicating a role for lifetime adiposity in carcinogenesis. PMID:26704725
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ge, Y; Keall, P; Poulsen, P
Purpose: Multiple targets with large intrafraction independent motion are often involved in advanced prostate, lung, abdominal, and head and neck cancer radiotherapy. Current standard of care treats these with the originally planned fields, jeopardizing the treatment outcomes. A real-time multi-leaf collimator (MLC) tracking method has been developed to address this problem for the first time. This study evaluates the geometric uncertainty of the multi-target tracking method. Methods: Four treatment scenarios are simulated based on a prostate IMAT plan to treat a moving prostate target and static pelvic node target: 1) real-time multi-target MLC tracking; 2) real-time prostate-only MLC tracking; 3)more » correcting for prostate interfraction motion at setup only; and 4) no motion correction. The geometric uncertainty of the treatment is assessed by the sum of the erroneously underexposed target area and overexposed healthy tissue areas for each individual target. Two patient-measured prostate trajectories of average 2 and 5 mm motion magnitude are used for simulations. Results: Real-time multi-target tracking accumulates the least uncertainty overall. As expected, it covers the static nodes similarly well as no motion correction treatment and covers the moving prostate similarly well as the real-time prostate-only tracking. Multi-target tracking reduces >90% of uncertainty for the static nodal target compared to the real-time prostate-only tracking or interfraction motion correction. For prostate target, depending on the motion trajectory which affects the uncertainty due to leaf-fitting, multi-target tracking may or may not perform better than correcting for interfraction prostate motion by shifting patient at setup, but it reduces ∼50% of uncertainty compared to no motion correction. Conclusion: The developed real-time multi-target MLC tracking can adapt for the independently moving targets better than other available treatment adaptations. This will enable PTV margin reduction to minimize health tissue toxicity while remain tumor coverage when treating advanced disease with independently moving targets involved. The authors acknowledge funding support from the Australian NHMRC Australia Fellowship and NHMRC Project Grant No. APP1042375.« less
[Image fusion: use in the control of the distribution of prostatic biopsies].
Mozer, Pierre; Baumann, Michaël; Chevreau, Grégoire; Troccaz, Jocelyne
2008-02-01
Prostate biopsies are performed under 2D TransRectal UltraSound (US) guidance by sampling the prostate according to a predefined pattern. Modern image processing tools allow better control of biopsy distribution. We evaluated the accuracy of a single operator performing a pattern of 12 ultrasound-guided biopsies by registering 3D ultrasound control images acquired after each biopsy. For each patient, prostate image alignment was performed automatically with a voxel-based registration algorithm allowing visualization of each biopsy trajectory in a single ultrasound reference volume. On average, the operator reached the target in 60% of all cases. This study shows that it is difficult to accurately reach targets in the prostate using 2D ultrasound. In the near future, real-time fusion of MRI and US images will allow selection of a target in previously acquired MR images and biopsy of this target by US guidance.
Gries, Katharine S; Regier, Dean A; Ramsey, Scott D; Patrick, Donald L
2017-06-01
To develop a statistical model generating utility estimates for prostate cancer specific health states, using preference weights derived from the perspectives of prostate cancer patients, men at risk for prostate cancer, and society. Utility estimate values were calculated using standard gamble (SG) methodology. Study participants valued 18 prostate-specific health states with the five attributes: sexual function, urinary function, bowel function, pain, and emotional well-being. Appropriateness of model (linear regression, mixed effects, or generalized estimating equation) to generate prostate cancer utility estimates was determined by paired t-tests to compare observed and predicted values. Mixed-corrected standard SG utility estimates to account for loss aversion were calculated based on prospect theory. 132 study participants assigned values to the health states (n = 40 men at risk for prostate cancer; n = 43 men with prostate cancer; n = 49 general population). In total, 792 valuations were elicited (six health states for each 132 participants). The most appropriate model for the classification system was a mixed effects model; correlations between the mean observed and predicted utility estimates were greater than 0.80 for each perspective. Developing a health-state classification system with preference weights for three different perspectives demonstrates the relative importance of main effects between populations. The predicted values for men with prostate cancer support the hypothesis that patients experiencing the disease state assign higher utility estimates to health states and there is a difference in valuations made by patients and the general population.
Relative Risks for Lethal Prostate Cancer Based on Complete Family History of Prostate Cancer Death.
Albright, Frederick S; Stephenson, Robert A; Agarwal, Neeraj; Cannon-Albright, Lisa A
2017-01-01
There are few published familial relative risks (RR) for lethal prostate cancer. This study estimates RRs for lethal prostate cancer based on comprehensive family history data, with the goal of improving identification of those men at highest risk of dying from prostate cancer. We used a population-based genealogical resource linked to a statewide electronic SEER cancer registry and death certificates to estimate relative risks (RR) for death from prostate cancer based upon family history. Over 600,000 male probands were analyzed, representing a variety of family history constellations of lethal prostate cancer. RR estimates were based on the ratio of the observed to the expected number of lethal prostate cancer cases using internal rates. RRs for lethal prostate cancer based on the number of affected first-degree relatives (FDR) ranged from 2.49 (95% CI: 2.27, 2.73) for exactly 1 FDR to 5.30 (2.13, 10.93) for ≥3 affected FDRs. In an absence of affected FDRs, increased risk was also significant for increasing numbers of affected second-degree or third degree relatives. Equivalent risks were observed for similar maternal and paternal family history. This study provides population-based estimates of lethal prostate cancer risk based on lethal prostate cancer family history. Many family history constellations associated with two to greater than five times increased risk for lethal prostate cancer were identified. These lethal prostate cancer risk estimates hold potential for use in identification, screening, early diagnosis, and treatment of men at high risk for death from prostate cancer. Prostate77:41-48, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Halpin, Michael; Phillips, Melanie; Oliffe, John L
2009-03-01
Despite the popularity of print media as an information source for men with prostate cancer, the representation of prostate cancer within this medium remains relatively understudied. This article details the findings from an analysis of prostate cancer articles published in two Canadian national newspapers, The Globe and Mail and the National Post, from January 2001 through to December 2006. The 817 prostate cancer articles published during this period were retrieved and reviewed using manifest and latent analyses. Three article categories, illness perspectives, medical perspectives and supplementary were identified in the manifest analysis. The latent analysis was guided by the connections between masculinities and prostate cancer in the newspapers' stories. Findings indicated a low frequency of articles that substantively discussed prostate cancer and that the descriptive content reproduced hegemonic masculine ideals, such as competition and stoicism. The presentation of a truncated illness trajectory and privileging of the curative aspects of biomedicine also depicted medicalised male bodies. Any discussion on the negative effects of treatment or explicit references to marginalized forms of masculinity was conspicuously absent. These findings support how representations of prostate cancer in Canadian newspapers predominately replicate detrimental ideologies and perspectives of men's health.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ipsen, S; Bruder, R; Schweikard, A
Purpose: While MLC tracking has been successfully used for motion compensation of moving targets, current real-time target localization methods rely on correlation models with x-ray imaging or implanted electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging yields volumetric data in real-time (4D) without ionizing radiation. We report the first results of online 4D ultrasound-guided MLC tracking in a phantom. Methods: A real-time tracking framework was installed on a 4D ultrasound station (Vivid7 dimension, GE) and used to detect a 2mm spherical lead marker inside a water tank. The volumetric frame rate was 21.3Hz (47ms). The marker wasmore » rigidly attached to a motion stage programmed to reproduce nine tumor trajectories (five prostate, four lung). The 3D marker position from ultrasound was used for real-time MLC aperture adaption. The tracking system latency was measured and compensated by prediction for lung trajectories. To measure geometric accuracy, anterior and lateral conformal fields with 10cm circular aperture were delivered for each trajectory. The tracking error was measured as the difference between marker position and MLC aperture in continuous portal imaging. For dosimetric evaluation, 358° VMAT fields were delivered to a biplanar diode array dosimeter using the same trajectories. Dose measurements with and without MLC tracking were compared to a static reference dose using a 3%/3 mm γ-test. Results: The tracking system latency was 170ms. The mean root-mean-square tracking error was 1.01mm (0.75mm prostate, 1.33mm lung). Tracking reduced the mean γ-failure rate from 13.9% to 4.6% for prostate and from 21.8% to 0.6% for lung with high-modulation VMAT plans and from 5% (prostate) and 18% (lung) to 0% with low modulation. Conclusion: Real-time ultrasound tracking was successfully integrated with MLC tracking for the first time and showed similar accuracy and latency as other methods while holding the potential to measure target motion non-invasively. SI was supported by the Graduate School for Computing in Medicine and Life Science, German Excellence Initiative [grant DFG GSC 235/1].« less
Screening for prostate cancer: estimating the magnitude of overdetection
McGregor, M; Hanley, J A; Boivin, J F; McLean, R G
1998-01-01
BACKGROUND: No randomized controlled trial of prostate cancer screening has been reported and none is likely to be completed in the near future. In the absence of direct evidence, the decision to screen must therefore be based on estimates of benefits and risks. The main risk of screening is overdetection--the detection of cancer that, if left untreated, would not cause death. In this study the authors estimate the level of overdetection that might result from annual screening of men aged 50-70. METHODS: The annual rate of lethal screen-detectable cancer (detectable cancer that would prove fatal before age 85 if left untreated) was calculated from the observed prostate cancer mortality rate in Quebec; the annual rate of all cases of screen-detectable prostate cancer was calculated from 2 recent screening studies. RESULTS: The annual rate of lethal screen-detectable prostate cancer was estimated to be 1.3 per 1000 men. The annual rate of all cases of screen-detectable prostate cancer was estimated to be 8.0 per 1000 men. The estimated case-fatality rate among men up to 85 years of age was 16% (1.3/8.0) (sensitivity analysis 13% to 22%). INTERPRETATION: Of every 100 men with screen-detected prostate cancer, only 16 on average (13 to 22) could have their lives extended by surgery, since the prostate cancer would not cause death before age 85 in the remaining 84 (78 to 87). PMID:9861205
New Image-Based Techniques for Prostate Biopsy and Treatment
2012-04-01
C-arm fluoroscopy, MICCAI 2011, Toronto, Canada, 2011. 4) Poster Presentation: Prostate Cancer Probability Estimation Based on DCE- DTI Features...and P. Kozlowski, “Prostate Cancer Probability Estimation Based on DCE- DTI Features and Support Vector Machine Classification,” Annual Meeting of... DTI ), which characterize the de-phasing of the MR signal caused by molecular diffusion. Prostate cancer causes a pathological change in the tissue
Goodman, Phyllis J.; Till, Cathee; Schenk, Jeannette M.; Lucia, M. Scott; Thompson, Ian M.
2016-01-01
Purpose To identify factors related to who undergoes a prostate biopsy in a screened population and to estimate the impact of biopsy verification on risk factor–prostate cancer associations. Patients and Methods Men who were screened regularly from the placebo arms of two large prostate cancer prevention trials (Prostate Cancer Prevention Trial [PCPT] and Selenium and Vitamin E Cancer Prevention Trial [SELECT]) were examined to define incident prostate cancer cohorts. Because PCPT had an end-of-study biopsy, prostate cancer cases were categorized by a preceding prostate-specific antigen/digital rectal examination prompt (yes/no) and noncases by biopsy-proven negative status (yes v no). We estimated the association of risk factors (age, ethnicity, family history, body mass index, medication use) with prostate cancer and quantified differences in risk associations across cohorts. Results Men 60 to 69 years of age, those with benign prostatic hyperplasia, and those with a family history of prostate cancer were more likely, and those with a higher body mass index (≥ 25), diabetes, or a smoking history were less likely, to undergo biopsy, adjusting for age and longitudinal prostate-specific antigen and digital rectal examination. Medication use, education, and marital status also influenced who underwent biopsy. Some risk factor estimates for prostate cancer varied substantially across cohorts. Black (v other ethnicities) had odds ratios (ORs) that varied from 1.20 for SELECT (community screening standards, epidemiologic-like cohort) to 1.83 for PCPT (end-of-study biopsy supplemented with imputed end points). Statin use in SELECT provided an OR of 0.65 and statin use in in PCPT provided an OR of 0.99, a relative difference of 34%. Conclusion Among screened men enrolled in prostate cancer prevention trials, differences in risk factor estimates for prostate cancer likely underestimate the magnitude of bias found in other cohorts with varying screening and biopsy recommendations and acceptance. Risk factors for prostate cancer derived from epidemiologic studies not only may be erroneous but may lead to misdirected research efforts. PMID:27998216
Design of a Teleoperated Needle Steering System for MRI-guided Prostate Interventions
Seifabadi, Reza; Iordachita, Iulian; Fichtinger, Gabor
2013-01-01
Accurate needle placement plays a key role in success of prostate biopsy and brachytherapy. During percutaneous interventions, the prostate gland rotates and deforms which may cause significant target displacement. In these cases straight needle trajectory is not sufficient for precise targeting. Although needle spinning and fast insertion may be helpful, they do not entirely resolve the issue. We propose robot-assisted bevel-tip needle steering under MRI guidance as a potential solution to compensate for the target displacement. MRI is chosen for its superior soft tissue contrast in prostate imaging. Due to the confined workspace of the MRI scanner and the requirement for the clinician to be present inside the MRI room during the procedure, we designed a MRI-compatible 2-DOF haptic device to command the needle steering slave robot which operates inside the scanner. The needle steering slave robot was designed to be integrated with a previously developed pneumatically actuated transperineal robot for MRI-guided prostate needle placement. We describe design challenges and present the conceptual design of the master and slave robots and the associated controller. PMID:24649480
Ares I-X Best Estimated Trajectory Analysis and Results
NASA Technical Reports Server (NTRS)
Karlgaard, Christopher D.; Beck, Roger E.; Starr, Brett R.; Derry, Stephen D.; Brandon, Jay; Olds, Aaron D.
2011-01-01
The Ares I-X trajectory reconstruction produced best estimated trajectories of the flight test vehicle ascent through stage separation, and of the first and upper stage entries after separation. The trajectory reconstruction process combines on-board, ground-based, and atmospheric measurements to produce the trajectory estimates. The Ares I-X vehicle had a number of on-board and ground based sensors that were available, including inertial measurement units, radar, air-data, and weather balloons. However, due to problems with calibrations and/or data, not all of the sensor data were used. The trajectory estimate was generated using an Iterative Extended Kalman Filter algorithm, which is an industry standard processing algorithm for filtering and estimation applications. This paper describes the methodology and results of the trajectory reconstruction process, including flight data preprocessing and input uncertainties, trajectory estimation algorithms, output transformations, and comparisons with preflight predictions.
Ares I-X Best Estimated Trajectory and Comparison with Pre-Flight Predictions
NASA Technical Reports Server (NTRS)
Karlgaard, Christopher D.; Beck, Roger E.; Derry, Stephen D.; Brandon, Jay M.; Starr, Brett R.; Tartabini, Paul V.; Olds, Aaron D.
2011-01-01
The Ares I-X trajectory reconstruction produced best estimated trajectories of the flight test vehicle ascent through stage separation, and of the first and upper stage entries after separation. The trajectory reconstruction process combines on-board, ground-based, and atmospheric measurements to produce the trajectory estimates. The Ares I-X vehicle had a number of on-board and ground based sensors that were available, including inertial measurement units, radar, air- data, and weather balloons. However, due to problems with calibrations and/or data, not all of the sensor data were used. The trajectory estimate was generated using an Iterative Extended Kalman Filter algorithm, which is an industry standard processing algorithm for filtering and estimation applications. This paper describes the methodology and results of the trajectory reconstruction process, including flight data preprocessing and input uncertainties, trajectory estimation algorithms, output transformations, and comparisons with preflight predictions.
Optical biopsy of the prostate: can we TRUST (trans-rectal ultrasound-coupled spectral tomography)?
NASA Astrophysics Data System (ADS)
Piao, Daqing; Jiang, Zhen; Bartels, Kenneth E.; Holyoak, G. Reed; Ritchey, Jerry W.; Rock, Kendra; Ownby, Charlotte L.; Bunting, Charles F.; Slobodov, Gennady
2011-03-01
Needle-based core-biopsy to locate prostate cancer relies heavily upon trans-rectal ultrasound (TRUS) imaging guidance. Ultrasonographic findings of classic hypoechoic peripheral zone lesions have a low specificity of ~28%, a low positive predictive value of ~29%, and an overall accuracy of ~43%, in prostate cancer diagnosis. The prevalence of isoechoic or nearly invisible prostate cancers on ultrasonography ranges from 25 to 42%. As a result, TRUS is useful and convenient to direct the needle trajectory following a systematic biopsy sampling template rather than to target only the potentially malignant lesion for focal-biopsy. To address this deficiency in the first-line of prostate cancer imaging, a trans-rectal ultrasound-coupled spectral tomography (TRUST) approach is being developed to non-invasively resolve the likely optical signatures of prostate malignancy. The approach has evolved from using one NIR wavelength to two NIR bands, and recently to three bands of NIR spectrum information. The concept has been evaluated on one normal canine prostate and three dogs with implanted prostate tumor developed as a model. The initial results implementing TRUST on the canine prostate tumor model includes: (1) quantifying substantially increased total hemoglobin concentration over the time-course of imaging in a rapidly growing prostate tumor; (2) confirming hypoxia in a prostatic cystic lesion; and (3) imaging hypoxic changes of a necrotic prostate tumor. Despite these interesting results, intensive technologic development is necessary for translating the approach to benefiting clinical practice, wherein the ultimate utility is not possibly to eliminate needle-biopsy but to perform focal-biopsy that is only necessary to confirm the cancer, as well as to monitor and predict treatment responses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takahashi, R; Kamima, T; Tachibana, H
2016-06-15
Purpose: To investigate the effect of the trajectory files from linear accelerator for Clarkson-based independent dose verification in IMRT and VMAT plans. Methods: A CT-based independent dose verification software (Simple MU Analysis: SMU, Triangle Products, Japan) with a Clarksonbased algorithm was modified to calculate dose using the trajectory log files. Eclipse with the three techniques of step and shoot (SS), sliding window (SW) and Rapid Arc (RA) was used as treatment planning system (TPS). In this study, clinically approved IMRT and VMAT plans for prostate and head and neck (HN) at two institutions were retrospectively analyzed to assess the dosemore » deviation between DICOM-RT plan (PL) and trajectory log file (TJ). An additional analysis was performed to evaluate MLC error detection capability of SMU when the trajectory log files was modified by adding systematic errors (0.2, 0.5, 1.0 mm) and random errors (5, 10, 30 mm) to actual MLC position. Results: The dose deviations for prostate and HN in the two sites were 0.0% and 0.0% in SS, 0.1±0.0%, 0.1±0.1% in SW and 0.6±0.5%, 0.7±0.9% in RA, respectively. The MLC error detection capability shows the plans for HN IMRT were the most sensitive and 0.2 mm of systematic error affected 0.7% dose deviation on average. Effect of the MLC random error did not affect dose error. Conclusion: The use of trajectory log files including actual information of MLC location, gantry angle, etc should be more effective for an independent verification. The tolerance level for the secondary check using the trajectory file may be similar to that of the verification using DICOM-RT plan file. From the view of the resolution of MLC positional error detection, the secondary check could detect the MLC position error corresponding to the treatment sites and techniques. This research is partially supported by Japan Agency for Medical Research and Development (AMED)« less
Ballistic projectile trajectory determining system
Karr, Thomas J.
1997-01-01
A computer controlled system determines the three-dimensional trajectory of a ballistic projectile. To initialize the system, predictions of state parameters for a ballistic projectile are received at an estimator. The estimator uses the predictions of the state parameters to estimate first trajectory characteristics of the ballistic projectile. A single stationary monocular sensor then observes the actual first trajectory characteristics of the ballistic projectile. A comparator generates an error value related to the predicted state parameters by comparing the estimated first trajectory characteristics of the ballistic projectile with the observed first trajectory characteristics of the ballistic projectile. If the error value is equal to or greater than a selected limit, the predictions of the state parameters are adjusted. New estimates for the trajectory characteristics of the ballistic projectile are made and are then compared with actual observed trajectory characteristics. This process is repeated until the error value is less than the selected limit. Once the error value is less than the selected limit, a calculator calculates trajectory characteristics such a the origin and destination of the ballistic projectile.
Ballistic projectile trajectory determining system
Karr, T.J.
1997-05-20
A computer controlled system determines the three-dimensional trajectory of a ballistic projectile. To initialize the system, predictions of state parameters for a ballistic projectile are received at an estimator. The estimator uses the predictions of the state parameters to estimate first trajectory characteristics of the ballistic projectile. A single stationary monocular sensor then observes the actual first trajectory characteristics of the ballistic projectile. A comparator generates an error value related to the predicted state parameters by comparing the estimated first trajectory characteristics of the ballistic projectile with the observed first trajectory characteristics of the ballistic projectile. If the error value is equal to or greater than a selected limit, the predictions of the state parameters are adjusted. New estimates for the trajectory characteristics of the ballistic projectile are made and are then compared with actual observed trajectory characteristics. This process is repeated until the error value is less than the selected limit. Once the error value is less than the selected limit, a calculator calculates trajectory characteristics such a the origin and destination of the ballistic projectile. 8 figs.
Wittmann, D; Mehta, A; Northouse, L; Dunn, R; Braun, T; Duby, A; An, L; Arab, L; Bangs, R; Bober, S; Brandon, J; Coward, M; Dunn, M; Galbraith, M; Garcia, M; Giblin, J; Glode, M; Koontz, B; Lowe, A; Mitchell, S; Mulhall, J; Nelson, C; Paich, K; Saigal, C; Skolarus, T; Stanford, J; Walsh, T; Pollack, C E
2017-10-02
Over half of men who receive treatment for prostate suffer from a range of sexual problems that affect negatively their sexual health, sexual intimacy with their partners and their quality of life. In clinical practice, however, care for the sexual side effects of treatment is often suboptimal or unavailable. The goal of the current study is to test a web-based intervention to support the recovery of sexual intimacy of prostate cancer survivors and their partners after treatment. The study team developed an interactive, web-based intervention, tailored to type of treatment received, relationship status (partnered/non-partnered) and sexual orientation. It consists of 10 modules, six follow the trajectory of the illness and four are theme based. They address sexual side effects, rehabilitation, psychological impacts and coaching for self-efficacy. Each includes a video to engage participants, psychoeducation and activities completed by participants on the web. Tailored strategies for identified concerns are sent by email after each module. Six of these modules will be tested in a randomized controlled trial and compared to usual care. Men with localized prostate cancer with partners will be recruited from five academic medical centers. These couples (N = 140) will be assessed prior to treatment, then 3 months and 6 months after treatment. The primary outcome will be the survivors' and partners' Global Satisfaction with Sex Life, assessed by a Patient Reported Outcome Measure Information Systems (PROMIS) measure. Secondary outcomes will include interest in sex, sexual activity, use of sexual aids, dyadic coping, knowledge about sexual recovery, grief about the loss of sexual function, and quality of life. The impact of the intervention on the couple will be assessed using the Actor-Partner Interaction Model, a mixed-effects linear regression model able to estimate both the association of partner characteristics with partner and patient outcomes and the association of patient characteristics with both outcomes. The web-based tool represents a novel approach to addressing the sexual health needs of prostate cancer survivors and their partners that-if found efficacious-will improve access to much needed specialty care in prostate cancer survivorship. Clinicaltrials.gov registration # NCT02702453 , registered on March 3, 2016.
Suzuki, Reiko; Allen, Naomi E; Key, Timothy J; Appleby, Paul N; Tjønneland, Anne; Johnsen, Nina Føns; Jensen, Majken K; Overvad, Kim; Boeing, Heiner; Pischon, Tobias; Kaaks, Rudolf; Rohrmann, Sabine; Trichopoulou, Antonia; Misirli, Gesthimani; Trichopoulos, Dimitrios; Bueno-de-Mesquita, H Bas; van Duijnhoven, Fränzel; Sacerdote, Carlotta; Pala, Valeria; Palli, Domenico; Tumino, Rosario; Ardanaz, Eva; Quirós, José Ramón; Larrañaga, Nerea; Sánchez, Maria-José; Tormo, María-José; Jakszyn, Paula; Johansson, Ingegerd; Stattin, Pär; Berglund, Göran; Manjer, Jonas; Bingham, Sheila; Khaw, Kay-Tee; Egevad, Lars; Ferrari, Pietro; Jenab, Mazda; Riboli, Elio
2009-01-01
Few studies have examined the association between dietary fiber intake and prostate cancer risk. We evaluated the association between dietary fiber intake and the risk of prostate cancer among 142,590 men in the European Prospective Investigation into Cancer and Nutrition (EPIC). Consumption of dietary fiber (total, cereal, fruit and vegetable fiber) was estimated by validated dietary questionnaires and calibrated using 24-hr dietary recalls. Incidence rate ratios were estimated using Cox regression and adjusted for potential confounding factors. During an average of 8.7 years follow-up, prostate cancer was diagnosed in 2,747 men. Overall, there was no association between dietary fiber intake (total, cereal, fruit or vegetable fiber) and prostate cancer risk, although calibrated intakes of total fiber and fruit fiber were associated with nonstatistically significant reductions in risk. There was no association between fiber derived from cereals or vegetables and risk and no evidence for heterogeneity in any of the risk estimates by stage or grade of disease. Our results suggest that dietary fiber intake is not associated with prostate cancer risk.
Attitude and Trajectory Estimation Using Earth Magnetic Field Data
NASA Technical Reports Server (NTRS)
Deutschmann, Julie; Bar-Itzhack, Itzhack Y.
1996-01-01
The magnetometer has long been a reliable, inexpensive sensor used in spacecraft momentum management and attitude estimation. Recent studies show an increased accuracy potential for magnetometer-only attitude estimation systems. Since the Earth's magnetic field is a function of time and position, and since time is known quite precisely, the differences between the computer and measured magnetic field components, as measured by the magnetometers throughout the entire spacecraft orbit, are a function of both the spacecraft trajectory and attitude errors. Therefore, these errors can be used to estimate both trajectory and attitude. Traditionally, satellite attitude and trajectory have been estimated with completely separate system, using different measurement data. Recently, trajectory estimation for low earth orbit satellites was successfully demonstrated in ground software using only magnetometer data. This work proposes a single augmented extended Kalman Filter to simultaneously and autonomously estimate both spacecraft trajectory and attitude with data from a magnetometer and either dynamically determined rates or gyro-measured body rates.
Accuracy and variability of tumor burden measurement on multi-parametric MRI
NASA Astrophysics Data System (ADS)
Salarian, Mehrnoush; Gibson, Eli; Shahedi, Maysam; Gaed, Mena; Gómez, José A.; Moussa, Madeleine; Romagnoli, Cesare; Cool, Derek W.; Bastian-Jordan, Matthew; Chin, Joseph L.; Pautler, Stephen; Bauman, Glenn S.; Ward, Aaron D.
2014-03-01
Measurement of prostate tumour volume can inform prognosis and treatment selection, including an assessment of the suitability and feasibility of focal therapy, which can potentially spare patients the deleterious side effects of radical treatment. Prostate biopsy is the clinical standard for diagnosis but provides limited information regarding tumour volume due to sparse tissue sampling. A non-invasive means for accurate determination of tumour burden could be of clinical value and an important step toward reduction of overtreatment. Multi-parametric magnetic resonance imaging (MPMRI) is showing promise for prostate cancer diagnosis. However, the accuracy and inter-observer variability of prostate tumour volume estimation based on separate expert contouring of T2-weighted (T2W), dynamic contrastenhanced (DCE), and diffusion-weighted (DW) MRI sequences acquired using an endorectal coil at 3T is currently unknown. We investigated this question using a histologic reference standard based on a highly accurate MPMRIhistology image registration and a smooth interpolation of planimetric tumour measurements on histology. Our results showed that prostate tumour volumes estimated based on MPMRI consistently overestimated histological reference tumour volumes. The variability of tumour volume estimates across the different pulse sequences exceeded interobserver variability within any sequence. Tumour volume estimates on DCE MRI provided the lowest inter-observer variability and the highest correlation with histology tumour volumes, whereas the apparent diffusion coefficient (ADC) maps provided the lowest volume estimation error. If validated on a larger data set, the observed correlations could support the development of automated prostate tumour volume segmentation algorithms as well as correction schemes for tumour burden estimation on MPMRI.
Suzuki, Taiji; Aihara, Kazuyuki
2013-09-01
These days prostate cancer is one of the most common types of malignant neoplasm in men. Androgen ablation therapy (hormone therapy) has been shown to be effective for advanced prostate cancer. However, continuous hormone therapy often causes recurrence. This results from the progression of androgen-dependent cancer cells to androgen-independent cancer cells during the continuous hormone therapy. One possible method to prevent the progression to the androgen-independent state is intermittent androgen suppression (IAS) therapy, which ceases dosing intermittently. In this paper, we propose two methods to estimate the dynamics of prostate cancer, and investigate the IAS therapy from the viewpoint of optimality. The two methods that we propose for dynamics estimation are a variational Bayesian method for a piecewise affine (PWA) system and a Gaussian process regression method. We apply the proposed methods to real clinical data and compare their predictive performances. Then, using the estimated dynamics of prostate cancer, we observe how prostate cancer behaves for various dosing schedules. It can be seen that the conventional IAS therapy is a way of imposing high cost for dosing while keeping the prostate cancer in a safe state. We would like to dedicate this paper to the memory of Professor Luigi M. Ricciardi. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Deutschmann, Julie; Bar-Itzhack, Itzhack
1997-01-01
Traditionally satellite attitude and trajectory have been estimated with completely separate systems, using different measurement data. The estimation of both trajectory and attitude for low earth orbit satellites has been successfully demonstrated in ground software using magnetometer and gyroscope data. Since the earth's magnetic field is a function of time and position, and since time is known quite precisely, the differences between the computed and measured magnetic field components, as measured by the magnetometers throughout the entire spacecraft orbit, are a function of both the spacecraft trajectory and attitude errors. Therefore, these errors can be used to estimate both trajectory and attitude. This work further tests the single augmented Extended Kalman Filter (EKF) which simultaneously and autonomously estimates spacecraft trajectory and attitude with data from the Rossi X-Ray Timing Explorer (RXTE) magnetometer and gyro-measured body rates. In addition, gyro biases are added to the state and the filter's ability to estimate them is presented.
Hirasawa, Yosuke; Kato, Yuji; Fujita, Kiichiro
2018-01-01
To investigate the predictive factors for transient urinary incontinence after transurethral enucleation with bipolar. We retrospectively analyzed the data of 584 patients who underwent transurethral enucleation with bipolar between December 2011 and September 2016 operated by a single surgeon. Urinary incontinence after transurethral enucleation with bipolar was defined as involuntary leakage of urine that required the use of pads. It was evaluated at 1 week, and 1, 3, 6, 12 and 24 months after transurethral enucleation with bipolar. We defined transient urinary incontinence as urinary incontinence persisting up to 1 month after transurethral enucleation with bipolar. Based on independent risk factors identified by a multivariate stepwise logistic regression analysis, a nomogram to predict transient urinary incontinence was developed. Of the 584 patients, 17.3%, 13.5%, 3.1%, 0.41%, and 0% patients had urinary incontinence at 1 week, 1, 3, 6 and 12 months after transurethral enucleation with bipolar, respectively. The mean (±standard error) age was 69.6 ± 0.26 years, estimated prostate volume was 54.7 ± 0.91 cm 3 , operative time was 58.0 ± 1.1 min and the prostate specimen weight was 30.6 ± 0.69 g. On univariate analysis, age, prostate volume estimated by transrectal ultrasonography, prostate-specific antigen, prostate specimen weight, operative time, prostate specimen weight/prostate volume and prostate specimen weight/operative time were significant predictive factors for transient urinary incontinence after transurethral enucleation with bipolar. On multivariate analysis, age (hazard ratio 1.07, P-value = 0.0034) and prostate volume (hazard ratio 1.03, P-value < 0.0001) were independent risk factors for transient urinary incontinence after transurethral enucleation with bipolar. Age and prostate volume estimated by transrectal ultrasonography seem to represent significant independent risk factors for transient urinary incontinence after transurethral enucleation with bipolar. This should be well discussed with the patient before surgery. © 2017 The Japanese Urological Association.
Hill, Deborah K.; Heindl, Andreas; Zormpas-Petridis, Konstantinos; Collins, David J.; Euceda, Leslie R.; Rodrigues, Daniel N.; Moestue, Siver A.; Jamin, Yann; Koh, Dow-Mu; Yuan, Yinyin; Bathen, Tone F.; Leach, Martin O.; Blackledge, Matthew D.
2017-01-01
Diffusion-weighted magnetic resonance imaging (DWI) enables non-invasive, quantitative staging of prostate cancer via measurement of the apparent diffusion coefficient (ADC) of water within tissues. In cancer, more advanced disease is often characterized by higher cellular density (cellularity), which is generally accepted to correspond to a lower measured ADC. A quantitative relationship between tissue structure and in vivo measurements of ADC has yet to be determined for prostate cancer. In this study, we establish a theoretical framework for relating ADC measurements with tissue cellularity and the proportion of space occupied by prostate lumina, both of which are estimated through automatic image processing of whole-slide digital histology samples taken from a cohort of six healthy mice and nine transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. We demonstrate that a significant inverse relationship exists between ADC and tissue cellularity that is well characterized by our model, and that a decrease of the luminal space within the prostate is associated with a decrease in ADC and more aggressive tumor subtype. The parameters estimated from our model in this mouse cohort predict the diffusion coefficient of water within the prostate-tissue to be 2.18 × 10−3 mm2/s (95% CI: 1.90, 2.55). This value is significantly lower than the diffusion coefficient of free water at body temperature suggesting that the presence of organelles and macromolecules within tissues can drastically hinder the random motion of water molecules within prostate tissue. We validate the assumptions made by our model using novel in silico analysis of whole-slide histology to provide the simulated ADC (sADC); this is demonstrated to have a significant positive correlation with in vivo measured ADC (r2 = 0.55) in our mouse population. The estimation of the structural properties of prostate tissue is vital for predicting and staging cancer aggressiveness, but prostate tissue biopsies are painful, invasive, and are prone to complications such as sepsis. The developments made in this study provide the possibility of estimating the structural properties of prostate tissue via non-invasive virtual biopsies from MRI, minimizing the need for multiple tissue biopsies and allowing sequential measurements to be made for prostate cancer monitoring. PMID:29250485
Yu, Xue Qin; Luo, Qingwei; Smith, David P; Clements, Mark S; Patel, Manish I; O'Connell, Dianne L
2017-01-01
To develop a method for estimating the future numbers of prostate cancer survivors requiring different levels of care. Analysis of population-based cancer registry data for prostate cancer cases (aged 18-84 years) diagnosed in 1996-2007, and a linked dataset with hospital admission data for men with prostate cancer diagnosed during 2005-2007 in New South Wales (NSW), Australia. Cancer registry data (1996-2007) were used to project complete prostate cancer prevalence in NSW, Australia for 2008-2017, and treatment information from hospital records (2005-2007) was used to estimate the inpatient care needs during the first year after diagnosis. The projected complete prevalence was divided into care needs-based groups. We first divided the cohort into two groups based on patient's age (<75 and 75-84 years). The younger cohort was further divided into initial care and monitoring phases. Cause of death data were used as a proxy for patients requiring last year of life prostate cancer care. Finally, episode data were used to estimate the future number of cases with metastatic progression. Of the estimated total of 60,910 men with a previous diagnosis of prostate cancer in 2017, the largest groups will be older patients (52.0%) and younger men who require monitoring (42.5%). If current treatment patterns continue, in the first year post-diagnosis 41% (1380) of patients (<75 years) will have a radical prostatectomy, and 52.6% (1752) will be likely to have either active surveillance, external beam radiotherapy or androgen deprivation therapy. About 3% will require care for subsequent metastases, and 1288 men with prostate cancer are likely to die from the disease in 2017. This method extends the application of routinely collected population-based data, and can contribute much to the knowledge of the number of men with prostate cancer and their health care requirements. This could be of significant use in planning future cancer care services and facilities in Australia.
Shen, Megan Johnson; Nelson, Christian J; Peters, Ellen; Slovin, Susan F; Hall, Simon J; Hall, Matt; Herrera, Phapichaya Chaoprang; Leventhal, Elaine A; Leventhal, Howard; Diefenbach, Michael A
2015-05-01
Prostate cancer survivors with a rising prostate-specific antigen (PSA) level have few treatment options, experience a heightened state of uncertainty about their disease trajectory that might include the possibility of cancer metastasis and death, and often experience elevated levels of distress as they have to deal with a disease they thought they had conquered. Guided by self-regulation theory, the present study examined the cognitive and affective processes involved in shared decision making between physicians and patients who experience a rising PSA after definitive treatment for prostate cancer. In-depth interviews were conducted with 34 prostate cancer survivors who had been diagnosed with a rising PSA (i.e., biochemical failure) within the past 12 months. Survivors were asked about their experiences and affective responses after being diagnosed with a rising PSA and while weighing potential treatment options. In addition, patients were asked about their decision-making process for the initial prostate cancer treatment. Compared with the initial diagnosis, survivors with a rising PSA reported increased negative affect following their diagnosis, concern about the treatability of their disease, increased planning and health behavior change, heightened levels of worry preceding doctor appointments (especially prior to the discussion of PSA testing results), and a strong reliance on physicians' treatment recommendations. Prostate cancer survivors' decision-making processes for the treatment of a rising PSA are markedly different from those of the initial diagnosis of prostate cancer. Because patients experience heightened distress and rely more heavily on their physicians' recommendations with a rising PSA, interactions with the health care provider provide an excellent opportunity to address and assist patients with managing the uncertainty and distress inherent with rising PSA levels. © The Author(s) 2014.
Pashayan, N; Powles, J; Brown, C; Duffy, S W
2006-01-01
This study aimed to estimate the extent of ‘overdiagnosis' of prostate cancer attributable to prostate-specific antigen (PSA) testing in the Cambridge area between 1996 and 2002. Overdiagnosis was defined conceptually as detection of prostate cancer through PSA testing that otherwise would not have been diagnosed within the patient's lifetime. Records of PSA tests in Addenbrookes Hospital were linked to prostate cancer registrations by NHS number. Differences in prostate cancer registration rates between those receiving and not receiving prediagnosis PSA tests were calculated. The proportion of men aged 40 years or over with a prediagnosis PSA test increased from 1.4 to 5.2% from 1996 to 2002. The rate of diagnosis of prostate cancer was 45% higher (rate ratios (RR)=1.45, 95% confidence intervals (CI) 1.02–2.07) in men with a history of prediagnosis PSA testing. Assuming average lead times of 5 to 10 years, 40–64% of the PSA-detected cases were estimated to be overdiagnosed. In East Anglia, from 1996 to 2000, a 1.6% excess of cases was associated with PSA testing (around a quarter of the 5.3% excess incidence cases observed in East Anglia from 1996 to 2000). Further quantification of the overdiagnosis will result from continued surveillance and from linkage of incidence to testing in other hospitals. PMID:16832417
Gorfine, Malka; Bordo, Nadia; Hsu, Li
2017-01-01
Summary Consider a popular case–control family study where individuals with a disease under study (case probands) and individuals who do not have the disease (control probands) are randomly sampled from a well-defined population. Possibly right-censored age at onset and disease status are observed for both probands and their relatives. For example, case probands are men diagnosed with prostate cancer, control probands are men free of prostate cancer, and the prostate cancer history of the fathers of the probands is also collected. Inherited genetic susceptibility, shared environment, and common behavior lead to correlation among the outcomes within a family. In this article, a novel nonparametric estimator of the marginal survival function is provided. The estimator is defined in the presence of intra-cluster dependence, and is based on consistent smoothed kernel estimators of conditional survival functions. By simulation, it is shown that the proposed estimator performs very well in terms of bias. The utility of the estimator is illustrated by the analysis of case–control family data of early onset prostate cancer. To our knowledge, this is the first article that provides a fully nonparametric marginal survival estimator based on case–control clustered age-at-onset data. PMID:27436674
Chiu, Peter K F; Roobol, Monique J; Teoh, Jeremy Y; Lee, Wai-Man; Yip, Siu-Ying; Hou, See-Ming; Bangma, Chris H; Ng, Chi-Fai
2016-10-01
To investigate PSA- and PHI (prostate health index)-based models for prediction of prostate cancer (PCa) and the feasibility of using DRE-estimated prostate volume (DRE-PV) in the models. This study included 569 Chinese men with PSA 4-10 ng/mL and non-suspicious DRE with transrectal ultrasound (TRUS) 10-core prostate biopsies performed between April 2008 and July 2015. DRE-PV was estimated using 3 pre-defined classes: 25, 40, or 60 ml. The performance of PSA-based and PHI-based predictive models including age, DRE-PV, and TRUS prostate volume (TRUS-PV) was analyzed using logistic regression and area under the receiver operating curves (AUC), in both the whole cohort and the screening age group of 55-75. PCa and high-grade PCa (HGPCa) was diagnosed in 10.9 % (62/569) and 2.8 % (16/569) men, respectively. The performance of DRE-PV-based models was similar to TRUS-PV-based models. In the age group 55-75, the AUCs for PCa of PSA alone, PSA with DRE-PV and age, PHI alone, PHI with DRE-PV and age, and PHI with TRUS-PV and age were 0.54, 0.71, 0.76, 0.78, and 0.78, respectively. The corresponding AUCs for HGPCa were higher (0.60, 0.70, 0.85, 0.83, and 0.83). At 10 and 20 % risk threshold for PCa, 38.4 and 55.4 % biopsies could be avoided in the PHI-based model, respectively. PHI had better performance over PSA-based models and could reduce unnecessary biopsies. A DRE-assessed PV can replace TRUS-assessed PV in multivariate prediction models to facilitate clinical use.
Are strict vegetarians protected against prostate cancer?
Tantamango-Bartley, Yessenia; Knutsen, Synnove F; Knutsen, Raymond; Jacobsen, Bjarne K; Fan, Jing; Beeson, W Lawrence; Sabate, Joan; Hadley, David; Jaceldo-Siegl, Karen; Penniecook, Jason; Herring, Patti; Butler, Terry; Bennett, Hanni; Fraser, Gary
2016-01-01
According to the American Cancer Society, prostate cancer accounts for ∼27% of all incident cancer cases among men and is the second most common (noncutaneous) cancer among men. The relation between diet and prostate cancer is still unclear. Because people do not consume individual foods but rather foods in combination, the assessment of dietary patterns may offer valuable information when determining associations between diet and prostate cancer risk. This study aimed to examine the association between dietary patterns (nonvegetarian, lacto-ovo-vegetarian, pesco-vegetarian, vegan, and semi-vegetarian) and prostate cancer incidence among 26,346 male participants of the Adventist Health Study-2. In this prospective cohort study, cancer cases were identified by matching to cancer registries. Cox proportional hazards regression analysis was performed to estimate HRs by using age as the time variable. In total, 1079 incident prostate cancer cases were identified. Around 8% of the study population reported adherence to the vegan diet. Vegan diets showed a statistically significant protective association with prostate cancer risk (HR: 0.65; 95% CI: 0.49, 0.85). After stratifying by race, the statistically significant association with a vegan diet remained only for the whites (HR: 0.63; 95% CI: 0.46, 0.86), but the multivariate HR for black vegans showed a similar but nonsignificant point estimate (HR: 0.69; 95% CI: 0.41, 1.18). Vegan diets may confer a lower risk of prostate cancer. This lower estimated risk is seen in both white and black vegan subjects, although in the latter, the CI is wider and includes the null. © 2016 American Society for Nutrition.
Are strict vegetarians protected against prostate cancer?1
Knutsen, Synnove F; Knutsen, Raymond; Jacobsen, Bjarne K; Fan, Jing; Beeson, W Lawrence; Sabate, Joan; Hadley, David; Jaceldo-Siegl, Karen; Penniecook, Jason; Herring, Patti; Butler, Terry; Bennett, Hanni; Fraser, Gary
2016-01-01
Background: According to the American Cancer Society, prostate cancer accounts for ∼27% of all incident cancer cases among men and is the second most common (noncutaneous) cancer among men. The relation between diet and prostate cancer is still unclear. Because people do not consume individual foods but rather foods in combination, the assessment of dietary patterns may offer valuable information when determining associations between diet and prostate cancer risk. Objective: This study aimed to examine the association between dietary patterns (nonvegetarian, lacto-ovo-vegetarian, pesco-vegetarian, vegan, and semi-vegetarian) and prostate cancer incidence among 26,346 male participants of the Adventist Health Study-2. Design: In this prospective cohort study, cancer cases were identified by matching to cancer registries. Cox proportional hazards regression analysis was performed to estimate HRs by using age as the time variable. Results: In total, 1079 incident prostate cancer cases were identified. Around 8% of the study population reported adherence to the vegan diet. Vegan diets showed a statistically significant protective association with prostate cancer risk (HR: 0.65; 95% CI: 0.49, 0.85). After stratifying by race, the statistically significant association with a vegan diet remained only for the whites (HR: 0.63; 95% CI: 0.46, 0.86), but the multivariate HR for black vegans showed a similar but nonsignificant point estimate (HR: 0.69; 95% CI: 0.41, 1.18). Conclusion: Vegan diets may confer a lower risk of prostate cancer. This lower estimated risk is seen in both white and black vegan subjects, although in the latter, the CI is wider and includes the null. PMID:26561618
Elshafei, Ahmed; Kovac, Evan; Dhar, Nivedita; Levy, David; Polascik, Thomas; Mouraviev, Vladimir; Yu, Changhong; Jones, J Stephen
2015-09-01
To create a predictive nomogram for biochemical failure following primary whole-gland cryoablation of the prostate for localized prostate cancer (LPCa). We retrospectively analyzed 2,242 patients from the Cryo On-Line Database (COLD) who were treatment naive and had undergone primary whole gland cryoablation of the prostate for biopsy-confirmed LPCa. Kaplan-Meier (KM) curves estimating 5 year biochemical progression-free survival (bPFS) were generated. Multivariable Cox proportional hazards analysis (CoxPH) was performed in order to construct the nomogram. The nomogram was internally validated using the bootstrap technique. Overall, the KM estimated 5 year bPFS was 72.8%. Stratified by D'Amico risk, The KM estimated 5 year bPFS was 82.6%, 71.1%, and 57.8% for low-, intermediate-, and high-risk groups, respectively. Statistically significant predictors of biochemical outcomes from CoxPH analysis were pre-treatment prostate specific antigen (PTPSA) (P < 0.001), total prostate volume (P = 0.004), clinical stage (P = 0.034), and Gleason score (0.004). A nomogram for predicted 5 year biochemical progression free probability was constructed with a concordance index of 0.652. An online risk calculator was also generated. To the best of our knowledge, this is the first predictive nomogram for biochemical outcomes after primary whole gland cryoablation of the prostate using socio-demographic, pretreatment, clinical, and prostate biopsy data. Our nomogram and online risk calculator can guide both patients and urologists for shared decision making regarding definitive treatment options. © 2015 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Li, Lu; Narayanan, Ramakrishnan; Miller, Steve; Shen, Feimo; Barqawi, Al B.; Crawford, E. David; Suri, Jasjit S.
2008-02-01
Real-time knowledge of capsule volume of an organ provides a valuable clinical tool for 3D biopsy applications. It is challenging to estimate this capsule volume in real-time due to the presence of speckles, shadow artifacts, partial volume effect and patient motion during image scans, which are all inherent in medical ultrasound imaging. The volumetric ultrasound prostate images are sliced in a rotational manner every three degrees. The automated segmentation method employs a shape model, which is obtained from training data, to delineate the middle slices of volumetric prostate images. Then a "DDC" algorithm is applied to the rest of the images with the initial contour obtained. The volume of prostate is estimated with the segmentation results. Our database consists of 36 prostate volumes which are acquired using a Philips ultrasound machine using a Side-fire transrectal ultrasound (TRUS) probe. We compare our automated method with the semi-automated approach. The mean volumes using the semi-automated and complete automated techniques were 35.16 cc and 34.86 cc, with the error of 7.3% and 7.6% compared to the volume obtained by the human estimated boundary (ideal boundary), respectively. The overall system, which was developed using Microsoft Visual C++, is real-time and accurate.
Bidirectional segmentation of prostate capsule from ultrasound volumes: an improved strategy
NASA Astrophysics Data System (ADS)
Wei, Liyang; Narayanan, Ramkrishnan; Kumar, Dinesh; Fenster, Aaron; Barqawi, Albaha; Werahera, Priya; Crawford, E. David; Suri, Jasjit S.
2008-03-01
Prostate volume is an indirect indicator for several prostate diseases. Volume estimation is a desired requirement during prostate biopsy, therapy and clinical follow up. Image segmentation is thus necessary. Previously, discrete dynamic contour (DDC) was implemented in orthogonal unidirectional on the slice-by-slice basis for prostate boundary estimation. This suffered from the glitch that it needed stopping criteria during the propagation of segmentation procedure from slice-to-slice. To overcome this glitch, axial DDC was implemented and this suffered from the fact that central axis never remains fixed and wobbles during propagation of segmentation from slice-to-slice. The effect of this was a multi-fold reconstructed surface. This paper presents a bidirectional DDC approach, thereby removing the two glitches. Our bidirectional DDC protocol was tested on a clinical dataset on 28 3-D ultrasound image volumes acquired using side fire Philips transrectal ultrasound. We demonstrate the orthogonal bidirectional DDC strategy achieved the most accurate volume estimation compared with previously published orthogonal unidirectional DDC and axial DDC methods. Compared to the ground truth, we show that the mean volume estimation errors were: 18.48%, 9.21% and 7.82% for unidirectional, axial and bidirectional DDC methods, respectively. The segmentation architecture is implemented in Visual C++ in Windows environment.
Eklund, Martin; Nordström, Tobias; Aly, Markus; Adolfsson, Jan; Wiklund, Peter; Brandberg, Yvonne; Thompson, James; Wiklund, Fredrik; Lindberg, Johan; Presti, Joseph C; StLezin, Mark; Clements, Mark; Egevad, Lars; Grönberg, Henrik
2016-11-23
Prostate cancer screening is associated with low specificity, unnecessary biopsies, and overdiagnosis. We have previously shown that the Stockholm-3 model (S3M) can reduce biopsies compared with using prostate-specific antigen (PSA) ≥3ng/ml as an indication for biopsy. Urologists in today's current prostate cancer testing (CPT) have access to numerous variables in addition to PSA (eg, age, ethnicity, family history, free PSA, PSA velocity, digital rectal examination, and prostate volume) to support biopsy decisions. We estimated the number of prostate cancers diagnosed and prostate biopsies performed if S3M replaced CPT in Stockholm, Sweden, by comparing biopsy results in 56 282 men who underwent PSA testing according to CPT in Stockholm in 2011 with the 47 688 men enrolled in the STHLM3 validation cohort 2012-2015. With the same sensitivity as CPT to diagnose Gleason score ≥7 prostate cancer, S3M was estimated to reduce the number of men biopsied by 53% (95% confidence interval [CI]: 41-65%), avoid 76% (95% CI: 67-81%) of negative biopsies, and reduce Gleason score 6 cancers by 23% (95% CI: 6-40%). S3M has the potential to improve prostate cancer diagnostics by better selecting men with high risk of GS ≥7 prostate cancer. We modeled the effect the Stockholm-3 model would have on prostate cancer diagnostics if it replaced current clinical practice. We found that Stockholm-3 model may substantially reduce the number of biopsies, while maintaining the same sensitivity to diagnose clinically significant prostate cancer. Copyright © 2016. Published by Elsevier B.V.
Scher, Howard I.; Solo, Kirk; Valant, Jason; Todd, Mary B.; Mehra, Maneesha
2015-01-01
Objective To identify patient populations most in need of treatment across the prostate cancer disease continuum, we developed a novel dynamic transition model based on risk of disease progression and mortality. Design and Outcome Measurements We modeled the flow of patient populations through eight prostate cancer clinical states (PCCS) that are characterized by the status of the primary tumor, presence of metastases, prior and current treatment, and testosterone levels. Simulations used published US incidence rates for each year from 1990. Progression and mortality rates were derived from published clinical trials, meta-analyses, and observational studies. Model outputs included the incidence, prevalence, and mortality for each PCCS. The impact of novel treatments was modeled in three distinct scenarios: metastatic castration-resistant prostate cancer (mCRPC), non-metastatic CRPC (nmCRPC), or both. Results and Limitations The model estimated the prevalence of prostate cancer as 2,219,280 in the US in 2009 and 3,072,480 in 2020, and incidence of mCRPC as 36,100 and 42,970, respectively. All-cause mortality in prostate cancer was estimated at 168,290 in 2009 and 219,360 in 2020, with 20.5% and 19.5% of these deaths, respectively, occurring in men with mCRPC. The majority (86%) of incidence flow into mCRPC states was from the nmCRPC clinical state. In the scenario with novel interventions for nmCRPC states, the progression to mCRPC is reduced, thus decreasing mCRPC incidence by 12% in 2020, with a sustained decline in mCRPC mortality. A limitation of the model is that it does not estimate prostate cancer—specific mortality. Conclusion The model informs clinical trial design for prostate cancer by quantifying outcomes in PCCS, and demonstrates the impact of an effective therapy applied in an earlier clinical state of nmCRPC on the incidence of mCRPC morbidity and subsequent mortality. PMID:26460686
Factors Affecting Prostate Volume Estimation in Computed Tomography Images
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Cheng-Hsiu; Wang, Shyh-Jen; Institute of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan
2011-04-01
The aim of this study was to investigate how apex-localizing methods and the computed tomography (CT) slice thickness affected the CT-based prostate volume estimation. Twenty-eight volunteers underwent evaluations of prostate volume by CT, where the contour segmentations were performed by three observers. The bottom of ischial tuberosities (ITs) and the bulb of the penis were used as reference positions to locate the apex, and the distances to the apex were recorded as 1.3 and 2.0 cm, respectively. Interobserver variations to locate ITs and the bulb of the penis were, on average, 0.10 cm (range 0.03-0.38 cm) and 0.30 cm (rangemore » 0.00-0.98 cm), respectively. The range of CT slice thickness varied from 0.08-0.48 cm and was adopted to examine the influence of the variation on volume estimation. The volume deviation from the reference case (0.08 cm), which increases in tandem with the slice thickness, was within {+-} 3 cm{sup 3}, regardless of the adopted apex-locating reference positions. In addition, the maximum error of apex identification was 1.5 times of slice thickness. Finally, based on the precise CT films and the methods of apex identification, there were strong positive correlation coefficients for the estimated prostate volume by CT and the transabdominal ultrasonography, as found in the present study (r > 0.87; p < 0.0001), and this was confirmed by Bland-Altman analysis. These results will help to identify factors that affect prostate volume calculation and to contribute to the improved estimation of the prostate volume based on CT images.« less
Performance of Trajectory Models with Wind Uncertainty
NASA Technical Reports Server (NTRS)
Lee, Alan G.; Weygandt, Stephen S.; Schwartz, Barry; Murphy, James R.
2009-01-01
Typical aircraft trajectory predictors use wind forecasts but do not account for the forecast uncertainty. A method for generating estimates of wind prediction uncertainty is described and its effect on aircraft trajectory prediction uncertainty is investigated. The procedure for estimating the wind prediction uncertainty relies uses a time-lagged ensemble of weather model forecasts from the hourly updated Rapid Update Cycle (RUC) weather prediction system. Forecast uncertainty is estimated using measures of the spread amongst various RUC time-lagged ensemble forecasts. This proof of concept study illustrates the estimated uncertainty and the actual wind errors, and documents the validity of the assumed ensemble-forecast accuracy relationship. Aircraft trajectory predictions are made using RUC winds with provision for the estimated uncertainty. Results for a set of simulated flights indicate this simple approach effectively translates the wind uncertainty estimate into an aircraft trajectory uncertainty. A key strength of the method is the ability to relate uncertainty to specific weather phenomena (contained in the various ensemble members) allowing identification of regional variations in uncertainty.
Kim, Seung Hyup
2008-01-01
Objective To evaluate the correlations between prostate volumes estimated by transabdominal, transrectal, and three-dimensional US and the factors affecting the differences. Materials and Methods The prostate volumes of 94 consecutive patients were measured by both transabdominal and transrectal US. Next, the prostate volumes of 58 other patients was measured by both transrectal and three-dimensional US. We evaluated the degree of correlation and mean difference in each comparison. We also analyzed possible factors affecting the differences, such as the experiences of examiners in transrectal US, bladder volume, and prostate volume. Results In the comparison of transabdominal and transrectal US methods, the mean difference was 8.4 ± 10.5 mL and correlation coefficient (r) was 0.775 (p < 0.01). The experienced examiner for the transrectal US method had the highest correlation (r = 0.967) and the significantly smallest difference (5.4 ± 3.9 mL) compared to the other examiners (the beginner and the trained; p < 0.05). Prostate volume measured by transrectal US showed a weak correlation with the difference (r = 0.360, p < 0.05). Bladder volume did not show significant correlation with the difference (r = -0.043, p > 0.05). The comparison between the transrectal and three-dimensional US methods revealed a mean difference of 3.7 ± 3.4 mL and the correlation coefficient was 0.924 for the experienced examiner. Furthermore, no significant difference existed between examiners (p > 0.05). Prostate volume measured by transrectal US showed a positive correlation with the difference for the beginner only (r = 0.405, p < 0.05). Conclusion In the prostate volume estimation by US, experience in transrectal US is important in the correlation with transabdominal US, but not with three-dimensional US. Also, less experienced examiners' assessment of the prostate volume can be affected by prostate volume itself. PMID:18385560
King's Health Partners' Prostate Cancer Biobank (KHP PCaBB).
Saifuddin, S R; Devlies, W; Santaolalla, A; Cahill, F; George, G; Enting, D; Rudman, S; Cathcart, P; Challacombe, B; Dasgupta, P; Galustian, C; Chandra, A; Chowdhury, S; Gillett, C; Van Hemelrijck, M
2017-11-22
The KHP PCaBB was established in 2013 and recruits donors from the Urology or Oncology Departments at Guy's Hospital in London (UK). Prostate cancer patients may be approached to give their consent for biobanking at any point in their treatment pathway, which allows residual material from their earlier diagnosis to be transferred and used by the Biobank. Currently, patients are specifically asked to donate samples of blood and surplus prostate tissue as well as permitting access to their clinical and pathological data that continues to be added throughout the course of their disease. Between 2013 and 2015, 549 prostate cancer patients gave their consent to the biobank and, the tissue repository collected 489 blood samples, 120 frozen prostate tissue samples and 1064 formalin fixed paraffin embedded diagnostic blocks.Prostate cancer has become a chronic disease in a large proportion of men, with many men receiving multiple subsequent treatments, and their treatment trajectory often spanning over decades. Therefore, this resource aims to provide an ideal research platform to explore potential variations in treatment response as well as disease markers in the different risk categories for prostate cancer.A recent audit of the KHP PCaBB revealed that between 2013 and 2015, 1796 patients were diagnosed with prostate cancer at King's Health Partners (KHP), out of which 549 (30.6%) gave their consent to KHP PCaBB. Comparisons between demographic and clinical characteristics of patients who had consented compared to the total patient population revealed that the KHP PCaBB is demographically representative of the total prostate cancer patient population seen in Guy's and St Thomas' NHS Foundation Trust (GSTT). We observed no differences in distribution of ethnicity (p = 0.507) and socioeconomic status (p = 0.097). Some differences were observed in clinical characteristics, specifically with treatment type - which differed significantly between the patients who had given consent and total patient population.The KHP PCaBB has thereby amassed a rich data and tissue repository that is largely reflective of both the demographic and clinical diversity within the total prostate cancer patient population seen at KHP, making it an ideal platform for prostate cancer research.
Revealing nonergodic dynamics in living cells from a single particle trajectory
NASA Astrophysics Data System (ADS)
Lanoiselée, Yann; Grebenkov, Denis S.
2016-05-01
We propose the improved ergodicity and mixing estimators to identify nonergodic dynamics from a single particle trajectory. The estimators are based on the time-averaged characteristic function of the increments and can thus capture additional information on the process as compared to the conventional time-averaged mean-square displacement. The estimators are first investigated and validated for several models of anomalous diffusion, such as ergodic fractional Brownian motion and diffusion on percolating clusters, and nonergodic continuous-time random walks and scaled Brownian motion. The estimators are then applied to two sets of earlier published trajectories of mRNA molecules inside live Escherichia coli cells and of Kv2.1 potassium channels in the plasma membrane. These statistical tests did not reveal nonergodic features in the former set, while some trajectories of the latter set could be classified as nonergodic. Time averages along such trajectories are thus not representative and may be strongly misleading. Since the estimators do not rely on ensemble averages, the nonergodic features can be revealed separately for each trajectory, providing a more flexible and reliable analysis of single-particle tracking experiments in microbiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyldesley, Scott, E-mail: styldesl@bccancer.bc.c; Delaney, Geoff; Foroudi, Farshad
Purpose: Estimates of the need for radiotherapy (RT) using different methods (criterion based benchmarking [CBB]and the Canadian [C-EBEST]and Australian [A-EBEST]epidemiologically based estimates) exist for various cancer sites. We compared these model estimates to actual RT rates for lung, breast, and prostate cancers in British Columbia (BC). Methods and Materials: All cases of lung, breast, and prostate cancers in BC from 1997 to 2004 and all patients receiving RT within 1 year (RT{sub 1Y}) and within 5 years (RT{sub 5Y}) of diagnosis were identified. The RT{sub 1Y} and RT{sub 5Y} proportions in health regions with a cancer center for the mostmore » recent year were then calculated. RT rates were compared with CBB and EBEST estimates of RT needs. Variation was assessed by time and region. Results: The RT{sub 1Y} in regions with a cancer center for lung, breast, and prostate cancers were 51%, 58%, and 33% compared with 45%, 57%, and 32% for C-EBEST and 41%, 61%, and 37% for CBB models. The RT{sub 5Y} rates in regions with a cancer center for lung, breast, and prostate cancers were 59%, 61%, and 40% compared with 61%, 66%, and 61% for C-EBEST and 75%, 83%, and 60% for A-EBEST models. The RT{sub 1Y} rates increased for breast and prostate cancers. Conclusions: C-EBEST and CBB model estimates are closer to the actual RT rates than the A-EBEST estimates. Application of these model estimates by health care decision makers should be undertaken with an understanding of the methods used and the assumptions on which they were based.« less
SU-F-T-42: MRI and TRUS Image Fusion as a Mode of Generating More Accurate Prostate Contours
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petronek, M; Purysko, A; Balik, S
Purpose: Transrectal Ultrasound (TRUS) imaging is utilized intra-operatively for LDR permanent prostate seed implant treatment planning. Prostate contouring with TRUS can be challenging at the apex and base. This study attempts to improve accuracy of prostate contouring with MRI-TRUS fusion to prevent over- or under-estimation of the prostate volume. Methods: 14 patients with previous MRI guided prostate biopsy and undergone an LDR permanent prostate seed implant have been selected. The prostate was contoured on the MRI images (1 mm slice thickness) by a radiologist. The prostate was also contoured on TRUS images (5 mm slice thickness) during LDR procedure bymore » a urologist. MRI and TRUS images were rigidly fused manually and the prostate contours from MRI and TRUS were compared using Dice similarity coefficient, percentage volume difference and length, height and width differences. Results: The prostate volume was overestimated by 8 ± 18% (range: 34% to −25%) in TRUS images compared to MRI. The mean Dice was 0.77 ± 0.09 (range: 0.53 to 0.88). The mean difference (TRUS-MRI) in the prostate width was 0 ± 4 mm (range: −11 to 5 mm), height was −3 ± 6 mm (range: −13 to 6 mm) and length was 6 ± 6 (range: −10 to 16 mm). Prostate was overestimated with TRUS imaging at the base for 6 cases (mean: 8 ± 4 mm and range: 5 to 14 mm), at the apex for 6 cases (mean: 11 ± 3 mm and range: 5 to 15 mm) and 1 case was underestimated at both base and apex by 4 mm. Conclusion: Use of intra-operative TRUS and MRI image fusion can help to improve the accuracy of prostate contouring by accurately accounting for prostate over- or under-estimations, especially at the base and apex. The mean amount of discrepancy is within a range that is significant for LDR sources.« less
Zanchetta, Margareth Santos; Cognet, Marguerite; Lam-Kin-Teng, Mary Rachel; Dumitriu, Marie Elisabeth; Renaud, Lise; Rhéaume, Jacques
2016-12-16
Survivors' testimonies can reveal much about men's experiences of prostate cancer and impacts on their quality of life (QOL) during the clinical trajectory of the disease. These survivors' shared thoughts and views were hypothesized to reflect salient features of their lived social representation of prostate cancer. We explored the content of testimonies posted by men to a public blog hosted by a French national prostate cancer patients' association. The study question, "What do French bloggers' testimonies reveal about their lived experiences with prostate cancer, especially regarding their quality of life in community settings, that underpin their social representation of prostate cancer?" guided the exploration and analysis of the textual data. The aims were to better understand men's experiences and predominant thoughts and views, to elucidate patients' behaviours, and to enlighten medical policy and practice. Explore issues of QOL as reported by French prostate cancer survivors in a public blog by: (a) identifying the salient aspects and issues of the experience of living with prostate cancer from the perspective of survivors; and (b) analyzing the content in the posted testimonies regarding perceived and lived impacts of prostate cancer on QOL. A critical ethnographic study guided the selection of textual data from 196 male bloggers' testimonies about prostate cancer posted in the period from 2008 to 2013. Media content analysis method was undertaken on blog testimonies, framed by a multidimensional conceptual framework of QOL. Testimonies focused mainly on medical care and rehabilitation, recovery, health education and self-care, as well as on a global vision of prostate cancer and its impacts on personal views of manhood and masculinity. The language used indicated that political, educative and compassionate discourses were intertwined to create a complex representation of the experience and effects of prostate cancer; this multi-faceted representation can inform the public and professional debate about men's capacity to provide emotional support and problem-solve within a community of interest. Findings, while based on data limited to mostly one-time entries to a French blog, contribute to understanding a unique, collective expression of men's lived experiences of prostate cancer. These anonymous survivors shared their varied reactions, ways of coping, and thoughts on needed change.
Allowable Trajectory Variations for Space Shuttle Orbiter Entry-Aeroheating CFD
NASA Technical Reports Server (NTRS)
Wood, William A.; Alter, Stephen J.
2008-01-01
Reynolds-number criteria are developed for acceptable variations in Space Shuttle Orbiter entry trajectories for use in computational aeroheating analyses. The criteria determine if an existing computational fluid dynamics solution for a particular trajectory can be extrapolated to a different trajectory. The criteria development begins by estimating uncertainties for seventeen types of computational aeroheating data, such as boundary layer thickness, at exact trajectory conditions. For each type of datum, the allowable uncertainty contribution due to trajectory variation is set to be half of the value of the estimated exact-trajectory uncertainty. Then, for the twelve highest-priority datum types, Reynolds-number relations between trajectory variation and output uncertainty are determined. From these relations the criteria are established for the maximum allowable trajectory variations. The most restrictive criterion allows a 25% variation in Reynolds number at constant Mach number between trajectories.
Rowe, Steven P; Macura, Katarzyna J; Mena, Esther; Blackford, Amanda L; Nadal, Rosa; Antonarakis, Emmanuel S; Eisenberger, Mario; Carducci, Michael; Fan, Hong; Dannals, Robert F; Chen, Ying; Mease, Ronnie C; Szabo, Zsolt; Pomper, Martin G; Cho, Steve Y
2016-06-01
Current standard of care conventional imaging modalities (CIM) such as X-ray computed tomography (CT) and bone scan can be limited for detection of metastatic prostate cancer and therefore improved imaging methods are an unmet clinical need. We evaluated the utility of a novel second-generation low molecular weight radiofluorinated prostate-specific membrane antigen (PSMA)-targeted positron emission tomography (PET) radiotracer, [(18)F]DCFPyL, in patients with metastatic prostate cancer. Nine patients with suspected prostate cancer recurrence, eight with CIM evidence of metastatic prostate cancer and one with biochemical recurrence, were imaged with [(18)F]DCFPyL PET/CT. Eight of the patients had contemporaneous CIM for comparison. A lesion-by-lesion comparison of the detection of suspected sites of metastatic prostate cancer was carried out between PET and CIM. Statistical analysis for estimated proportions of inter-modality agreement for detection of metastatic disease was calculated accounting for intra-patient correlation using general estimating equation (GEE) intercept-only regression models. One hundred thirty-nine sites of PET positive [(18)F]DCFPyL uptake (138 definite, 1 equivocal) for metastatic disease were detected in the eight patients with available comparison CIM. By contrast, only 45 lesions were identified on CIM (30 definite, 15 equivocal). When lesions were negative or equivocal on CIM, it was estimated that a large portion of these lesions or 0.72 (95 % confidence interval (CI) 0.55-0.84) would be positive on [(18)F]DCFPyL PET. Conversely, of those lesions negative or equivocal on [(18)F]DCFPyL PET, it was estimated that only a very small proportion or 0.03 (95 % CI 0.01-0.07) would be positive on CIM. Delayed 2-h-post-injection time point PET yielded higher tumor radiotracer uptake and higher tumor-to-background ratios than an earlier 1-h-post-injection time point. A novel PSMA-targeted PET radiotracer, [(18)F]DCFPyL, was able to a large number of suspected sites of prostate cancer, many of which were occult or equivocal by CIM. This study provides strong preliminary evidence for the use of this second-generation PSMA-targeted PET radiotracer for detection of metastatic prostate cancer and lends further support for the importance of PSMA-targeted PET imaging in prostate cancer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, D; Usmani, N; Sloboda, R
The study investigated the movement of implanted brachytherapy seeds upon transrectal US probe removal, providing insight into the underlying prostate deformation and an estimate of the impact on prostate dosimetry. Implanted seed distributions, one obtained with the prostate under probe compression and another with the probe removed, were reconstructed using C-arm fluoroscopy imaging. The prostate, delineated on ultrasound images, was registered to the fluoroscopy images using seeds and needle tracks identified on ultrasound. A deformation tensor and shearing model was developed to correlate probe-induced seed movement with position. Changes in prostate TG-43 dosimetry were calculated. The model was used tomore » infer the underlying prostate deformation and to estimate the location of the prostate surface in the absence of probe compression. Seed movement patterns upon probe removal reflected elastic decompression, lateral shearing, and rectal bending. Elastic decompression was characterized by expansion in the anterior-posterior direction and contraction in the superior-inferior and lateral directions. Lateral shearing resulted in large anterior movement for extra-prostatic seeds in the lateral peripheral region. Whole prostate D90 increased up to 8 Gy, mainly due to the small but systematic seed movement associated with elastic decompression. For selected patients, lateral shearing movement increased prostate D90 by 4 Gy, due to increased dose coverage in the anterior-lateral region at the expense of the posterior-lateral region. The effect of shearing movement on whole prostate D90 was small compared to elastic decompression due to the subset of peripheral seeds involved, but is expected to have greater consequences for local dose coverage.« less
Rossi, Peter J; Urbanic, James; Clark, Peter E; McCullough, David L; Lee, W Robert
2008-01-01
This report examines the relationship between pretreatment prostate-specific antigen (PSA) velocity (PSAV) and freedom from biochemical recurrence (FFBR) in men with prostate cancer treated with low-dose-rate prostate brachytherapy (LDRPB). This is a report of 51 men treated with LDRPB between 1997 and 1999. two or more evaluable PSA values >3 months apart and <18 months before treatment. PSAV is calculated using a linear regression equation. All patients had biopsy confirmed, clinically localized prostate cancer. All men were treated with (125)I LDRPB. The prescription dose was 144Gy. Biochemical failure is determined from PSA values over time using the ASTRO Consensus Definition. FFBR is estimated using Kaplan-Meier method. Pretreatment variables analyzed include percentage positive biopsy cores, D(90), risk group, and PSAV. All p values are two-sided. The median followup is 60 months. The median pretreatment PSA is 6.5, 75% of men were Stage T1c, and 88% had Gleason score > or =6; 10% developed evidence of biochemical recurrence at a median of 13 months (range, 6-36). The 6-year estimate of FFBR is 90% for the entire cohort. On univariate analysis, pretreatment PSAV and risk group are associated with FFBR. The 6-year estimate of FFBR in patients with a PSAV <2 ng/mL/yr is 100% vs. 80% (95% confidence interval: 64-96%) when the pretreatment PSAV is > or =2 ng/mL/yr before LDRPB (p = 0.017). Pretreatment PSAV is a predictor of FFBR after LDRPB in this population of men with prostate cancer. Men with a pretreatment PSAV > or =2 ng/mL/yr may warrant more aggressive treatment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewis, C; Jiang, R; Chow, J
2015-06-15
Purpose: We developed a method to predict the change of DVH for PTV due to interfraction organ motion in prostate VMAT without repeating the CT scan and treatment planning. The method is based on a pre-calculated patient database with DVH curves of PTV modelled by the Gaussian error function (GEF). Methods: For a group of 30 patients with different prostate sizes, their VMAT plans were recalculated by shifting their PTVs 1 cm with 10 increments in the anterior-posterior, left-right and superior-inferior directions. The DVH curve of PTV in each replan was then fitted by the GEF to determine parameters describingmore » the shape of curve. Information of parameters, varying with the DVH change due to prostate motion for different prostate sizes, was analyzed and stored in a database of a program written by MATLAB. Results: To predict a new DVH for PTV due to prostate interfraction motion, prostate size and shift distance with direction were input to the program. Parameters modelling the DVH for PTV were determined based on the pre-calculated patient dataset. From the new parameters, DVH curves of PTVs with and without considering the prostate motion were plotted for comparison. The program was verified with different prostate cases involving interfraction prostate shifts and replans. Conclusion: Variation of DVH for PTV in prostate VMAT can be predicted using a pre-calculated patient database with DVH curve fitting. The computing time is fast because CT rescan and replan are not required. This quick DVH estimation can help radiation staff to determine if the changed PTV coverage due to prostate shift is tolerable in the treatment. However, it should be noted that the program can only consider prostate interfraction motions along three axes, and is restricted to prostate VMAT plan using the same plan script in the treatment planning system.« less
Body image predicts quality of life in men with prostate cancer.
Taylor-Ford, Megan; Meyerowitz, Beth E; D'Orazio, Lina M; Christie, Kysa M; Gross, Mitchell E; Agus, David B
2013-04-01
Most men diagnosed with prostate cancer in the USA will survive. Of the many aspects of survivorship affected by prostate cancer, body image receives limited attention despite some indication that it may be important to men with the disease. The present study investigated how body image changes over time and the relations between changes in body image and quality of life (QOL) in men with prostate cancer. In a longitudinal design, patients (N = 74) completed questionnaires before treatment (T1) and at 1 month (T2) and 2 years (T3) following treatment completion. Growth curve modeling indicated that there was no significant change over time in group-level body image scores. However, hormone treatment was associated with a negative trajectory of change over 2 years. Also, analysis of individual difference scores indicated that ≥50% of patients demonstrated change of at least 0.5 standard deviation between time points. Hierarchical regression indicated that change in body image between T1 and T2 was significantly associated with change in QOL between T1 and T3, while controlling for demographic variables, treatment, treatment-related functioning, and general and treatment-specific positive expectations. In predicting change in body image between T1 and T2, treatment-specific positive expectation was the only significant predictor. The present study demonstrates that body image is an important component of the prostate cancer experience. Findings suggest that body image has a meaningful association with QOL among prostate cancer survivors. Copyright © 2012 John Wiley & Sons, Ltd.
Oliffe, John L; Bottorff, Joan L; McKenzie, Michael M; Hislop, T Gregory; Gerbrandt, Julieta S; Oglov, Valerie
2011-11-01
In this article we describe the connections between prostate cancer support groups (PCSGs) and men's health literacy and consumer orientation to health care services. The study findings are drawn from participant observations conducted at 16 PCSGs in British Columbia, Canada and 54 individual interviews that focused on men's experiences of attending group meetings. Men's communication and interactions at PCSGs provide important insights for how men talk about and conceptualize health and illness. For example, biomedical language often predominated at group meetings, and men used numbers and measures to engage with risk discourses in linking prostate cancer markers to various treatment options and morbidity and mortality rates. Many groups afforded opportunities for men to interact with health care providers as a means to better understand the language and logic of prostate cancer management. The health literacy skills fostered at PCSGs along with specific group-informed strategies could be mobilized in the men's subsequent clinical consultations. Consumer discourses and strategies to contest power relations with health care professionals underpinned many men's search for prostate cancer information and their commitment to assisting other men. Key were patients' rights, and perhaps responsibility, to compare diverse health products and services in making decisions across the entire trajectory of their prostate cancer. Overall, the study findings reveal PCSGs as having the capacity to contest as well as align with medical expertise and services facilitating men's transition from patient to informed health care consumers. The processes through which this occurs may direct the design of older men's health promotion programs.
Dahl, Sigrun; Loge, Jon Håvard; Berge, Viktor; Dahl, Alv Andreas; Cvancarova, Milada; Fosså, Sophie Dorothea
2015-06-01
The purpose of this study is to study the influence of radical prostatectomy (RP) for prostate cancer on work status and working life in men 3 years after surgery. In a prospective, questionnaire-based study on adverse effects after RP, 330 prostate cancer (PCa) patients who had been active in the workforce before RP described their work status 3 years after having surgery. We dichotomized their postoperative work status into "unchanged or increased" versus "reduced." The participants also reported whether their working life was influenced by the PCa trajectory to no, some, or a great extent. Univariate and multiple logistic regression models were established with sociodemographic and clinical characteristics as independent variables and "work status" or "influence of PCa trajectory on working life" as dependent variables. Twenty-five percent of the participants had retired. Of the remaining participants, approximately 20 % had a reduced work status, which in the multivariate analyses was significantly associated with increasing age. One third of the men still active in the workforce considered the PCa to negatively influence their working life. This was independently associated with bother related to urinary leakage, fatigue, and having undergone additional oncological therapy (pelvic radiotherapy and/or hormone treatment). Though RP does not affect work status in most men, approximately one third of them experience problems in their working life due to adverse effects related to RP and/or additional post-RP anti-cancer therapy. Most PCa survivors can expect to remain in the workforce for at least 3 years after RP, but for some, persistent adverse effects after RP and /or additional anti-cancer treatment negatively affect their working life. Pre-RP counseling of men within the workforce should cover possible post-RP changes concerning work status and working life.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hassan Rezaeian, N; Chi, Y; Zhou, Y
2016-06-15
Purpose: We are conducting a clinical trial on stereotactic body radiation therapy (SBRT) for high-risk prostate cancer. Doses to three targets, prostate, intra-prostatic lesion, and pelvic lymph node (PLN) region, are escalated to three different levels via simultaneous integrated boost technique. Inter-/intra-fractional organ motions deteriorate planned dose distribution. This study aims at developing a dose reconstruction system to comprehensively understand the impacts of organ motion in our clinical trial. Methods: A 4D dose reconstruction system has been developed for this study. Using a GPU-based Monte-Carlo dose engine and delivery log file, the system is able to reconstruct dose on staticmore » or dynamic anatomy. For prostate and intra-prostatic targets, intra-fractional motion is the main concern. Motion trajectory acquired from Calypso in previously treated SBRT patients were used to perform 4D dose reconstructions. For pelvic target, inter-fractional motion is one concern. Eight patients, each with four cone beam CTs, were used to derive fractional motion. The delivered dose was reconstructed on the deformed anatomy. Dosimetric parameters for delivered dose distributions of the three targets were extracted and compared with planned levels. Results: For prostate intra-fractional motion, the mean 3D motion amplitude during beam delivery ranged from 1.5mm to 5.0mm and the average among all patients was 2.61mm. Inter-fractional motion for the PLN target was more significant. The average amplitude among patients was 4mm with the largest amplitude up to 9.6mm. The D95% deviation from planned level for prostate PTVs and GTVs are on average less than<0.1% and this deviation for intra-prostatic lesion PTVs and GTVs were more prominent. The dose at PLN was significantly affected with D{sub 95}% reduced by up to 44%. Conclusion: Intra-/inter-fractional organ motion is a concern for high-risk prostate SBRT, particularly for the PLN target. Our dose reconstruction approach can also serve as the basis to guide treatment adaptation.« less
Simulating intrafraction prostate motion with a random walk model.
Pommer, Tobias; Oh, Jung Hun; Munck Af Rosenschöld, Per; Deasy, Joseph O
2017-01-01
Prostate motion during radiation therapy (ie, intrafraction motion) can cause unwanted loss of radiation dose to the prostate and increased dose to the surrounding organs at risk. A compact but general statistical description of this motion could be useful for simulation of radiation therapy delivery or margin calculations. We investigated whether prostate motion could be modeled with a random walk model. Prostate motion recorded during 548 radiation therapy fractions in 17 patients was analyzed and used for input in a random walk prostate motion model. The recorded motion was categorized on the basis of whether any transient excursions (ie, rapid prostate motion in the anterior and superior direction followed by a return) occurred in the trace and transient motion. This was separately modeled as a large step in the anterior/superior direction followed by a returning large step. Random walk simulations were conducted with and without added artificial transient motion using either motion data from all observed traces or only traces without transient excursions as model input, respectively. A general estimate of motion was derived with reasonable agreement between simulated and observed traces, especially during the first 5 minutes of the excursion-free simulations. Simulated and observed diffusion coefficients agreed within 0.03, 0.2 and 0.3 mm 2 /min in the left/right, superior/inferior, and anterior/posterior directions, respectively. A rapid increase in variance at the start of observed traces was difficult to reproduce and seemed to represent the patient's need to adjust before treatment. This could be estimated somewhat using artificial transient motion. Random walk modeling is feasible and recreated the characteristics of the observed prostate motion. Introducing artificial transient motion did not improve the overall agreement, although the first 30 seconds of the traces were better reproduced. The model provides a simple estimate of prostate motion during delivery of radiation therapy.
Renal donors with prostate cancer, no longer a reason to decline.
Dholakia, S; Johns, R; Muirhead, L; Papalois, V; Crane, J
2016-01-01
To fully assess the true risk of prostate cancer transmission in during renal transplantation. A full review of all existing literature relevant to the topic. There has not been a single documented case of transmission of prostate cancer during renal transplant. Prostate cancer in deceased organ donors has an incidence estimated between 3% and 18.5% and over 100 transplants have been performed using organs from donor with proven prostate cancer without issue. Transmission of prostate cancer through kidney transplantation seems very unlikely. The risks of remaining on the waiting list are outweighed by a transmission risk and the potential benefit makes the case to have clear guidelines about donor prostate malignancy when accepting potential organs. Copyright © 2015. Published by Elsevier Inc.
Mervin, Merehau C; Lowe, Anthony; Gardiner, Robert A; Smith, David P; Aitken, Joanne; Chambers, Suzanne K; Gordon, Louisa G
2017-06-01
To estimate costs on the Medicare Benefits Schedule (MBS) and the Pharmaceutical Benefits Scheme (PBS) attributable to the diagnosis and treatment of prostate cancer. We used data from a cohort study of 1064 men with localized prostate cancer recruited between 2005 and 2007 by 24 urologists across 10 sites in Queensland, Australia (ProsCan). We estimated the MBS and PBS costs attributable to prostate cancer from the date of initial appointment to 12 months after diagnosis in 2013 Australian dollars using a comparison group without prostate cancer. We used generalized linear modeling to identify key determinants of higher treatment-related costs. From the date of initial appointment to 12 months postdiagnosis, the average MBS costs attributable to prostate cancer were $9,357 (SD $191) per patient. These MBS costs were most sensitive to having private health insurance and the type of primary treatment received. The PBS costs were higher in the control group than in the ProsCan group ($5,641 vs $1,924). The costs of treating and managing prostate cancer are high and these result in a substantial financial burden for the Australian MBS. Costs attributable to prostate cancer appear to vary widely based on initial treatment and these are likely to increase with the introduction of more expensive services and pharmaceuticals. There is a pressing need for better prognostic tools to distinguish between indolent and aggressive prostate tumors to reduce potential over treatment and help ease the burden of prostate cancer. © 2017 John Wiley & Sons Australia, Ltd.
Age-dependent associations between androgenetic alopecia and prostate cancer risk.
Muller, David C; Giles, Graham G; Sinclair, Rod; Hopper, John L; English, Dallas R; Severi, Gianluca
2013-02-01
Both prostate cancer and androgenetic alopecia are strongly age-related conditions that are considered to be androgen dependent, but studies of the relationship between them have yielded inconsistent results. We aimed to assess whether androgenetic alopecia at ages 20 and 40 years are associated with risk of prostate cancer. At a follow-up of the Melbourne Collaborative Cohort Study, men were asked to assess their hair pattern at ages 20 and 40 years relative to eight categories in showcards. Cases were men notified to the Victorian Cancer Registry with prostate cancer diagnosed between cohort enrollment (1990-1994) and follow-up attendance (2003-2009). Flexible parametric survival models were used to estimate age-varying HRs and predicted cumulative probabilities of prostate cancer by androgenetic alopecia categories. Of 9,448 men that attended follow-up and provided data on androgenetic alopecia, we identified 476 prostate cancer cases during a median follow-up of 11 years four months. Cumulative probability of prostate cancer was greater at all ages up to 76 years, for men with vertex versus no androgenetic alopecia at age of 40 years. At age of 76 years, the estimated probabilities converged to 0.15. Vertex androgenetic alopecia at 40 years was also associated with younger age of diagnosis for prostate cancer cases. Vertex androgenetic alopecia at age of 40 years might be a marker of increased risk of early-onset prostate cancer. If confirmed, these results suggest that the apparently conflicting findings of previous studies might be explained by failure to adequately model the age-varying nature of the association between androgenetic alopecia and prostate cancer.
Trajectory Planning by Preserving Flexibility: Metrics and Analysis
NASA Technical Reports Server (NTRS)
Idris, Husni R.; El-Wakil, Tarek; Wing, David J.
2008-01-01
In order to support traffic management functions, such as mitigating traffic complexity, ground and airborne systems may benefit from preserving or optimizing trajectory flexibility. To help support this hypothesis trajectory flexibility metrics have been defined in previous work to represent the trajectory robustness and adaptability to the risk of violating safety and traffic management constraints. In this paper these metrics are instantiated in the case of planning a trajectory with the heading degree of freedom. A metric estimation method is presented based on simplifying assumptions, namely discrete time and heading maneuvers. A case is analyzed to demonstrate the estimation method and its use in trajectory planning in a situation involving meeting a time constraint and avoiding loss of separation with nearby traffic. The case involves comparing path-stretch trajectories, in terms of adaptability and robustness along each, deduced from a map of estimated flexibility metrics over the solution space. The case demonstrated anecdotally that preserving flexibility may result in enhancing certain factors that contribute to traffic complexity, namely reducing proximity and confrontation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Margalit, Danielle N., E-mail: dmargalit@lroc.harvard.edu; Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts
2012-05-01
Purpose: The safety of antioxidant supplementation during radiation therapy (RT) for cancer is controversial. Antioxidants could potentially counteract the pro-oxidant effects of RT and compromise therapeutic efficacy. We performed a prospective study nested within the Physicians' Health Study (PHS) randomized trial to determine if supplemental antioxidant use during RT for prostate cancer is associated with an increased risk of prostate cancer death or metastases. Methods and Materials: PHS participants (383) received RT for prostate cancer while randomized to receive beta-carotene (50 mg on alternate days) or placebo. The primary endpoint was time from RT to lethal prostate cancer, defined asmore » prostate cancer death or bone metastases. The Kaplan-Meier method was used to estimate survival probabilities and the log-rank test to compare groups. Cox proportional hazards regression was used to estimate the effect of beta-carotene compared with that of placebo during RT. Results: With a median follow-up of 10.5 years, there was no significant difference between risk of lethal prostate cancer with the use of beta-carotene during RT compared with that of placebo (hazard ratio = 0.72; 95% confidence interval [CI], 0.42-1.24; p = 0.24). After we adjusted for age at RT, prostate-specific antigen serum level, Gleason score, and clinical stage, the difference remained nonsignificant. The 10-year freedom from lethal prostate cancer was 92% (95% CI, 87-95%) in the beta-carotene group and 89% (95% CI, 84-93%) in the placebo group. Conclusion: The use of supplemental antioxidant beta-carotene during RT was not associated with an increased risk of prostate cancer death or metastases. This study suggests a lack of harm from supplemental beta-carotene during RT for prostate cancer.« less
NASA Astrophysics Data System (ADS)
Shinnaka, Shinji
This paper presents a new unified analysis of estimate errors by model-matching extended-back-EMF estimation methods for sensorless drive of permanent-magnet synchronous motors. Analytical solutions about estimate errors, whose validity is confirmed by numerical experiments, are rich in universality and applicability. As an example of universality and applicability, a new trajectory-oriented vector control method is proposed, which can realize directly quasi-optimal strategy minimizing total losses with no additional computational loads by simply orienting one of vector-control coordinates to the associated quasi-optimal trajectory. The coordinate orientation rule, which is analytically derived, is surprisingly simple. Consequently the trajectory-oriented vector control method can be applied to a number of conventional vector control systems using model-matching extended-back-EMF estimation methods.
Synergistic interaction of benign prostatic hyperplasia and prostatitis on prostate cancer risk
Hung, S-C; Lai, S-W; Tsai, P-Y; Chen, P-C; Wu, H-C; Lin, W-H; Sung, F-C
2013-01-01
Background: The incidence of prostate cancer is much lower in Asian men than in Western men. This study investigated whether prostate cancer is associated with prostatitis, benign prostatic hyperplasia (BPH), and other medical conditions in the low-incidence population. Methods: From the claims data obtained from the universal National Health Insurance of Taiwan, we identified 1184 patients with prostate cancer diagnosed from 1997 to 2008. Controls comprised 4736 men randomly selected from a cancer-free population. Both groups were 50 years of age or above. Medical histories between the two groups were compared. Results: Multivariate logistic regression analysis showed that prostatitis and BPH had stronger association with prostate cancer than the other medical conditions tested. Compared with men without prostatitis and BPH, a higher odds ratio (OR) for prostate cancer was associated with BPH (26.2, 95% confidence interval (CI) 20.8–33.0) than with prostatitis (10.5, 95% CI=3.36–32.7). Men with both conditions had an OR of 49.2 (95% CI=34.7–69.9). Conclusion: Men with prostate cancer have strong association with prostatitis and/or BPH. Prostatitis interacts with BPH, resulting in higher estimated relative risk of prostate cancer in men suffering from both conditions. PMID:23612451
Reduction of Racial Disparities in Prostate Cancer
2006-12-01
hyperplasia, interstitial cystitis/chronic pelvic pain, prostatitis, hypogonadism/androgen deficiency, erectile dysfunction , female sexual...socioeconomically diverse, community-based sample of adults aged 30–79 years in Boston, Massachusetts. This report gives estimates from the 2301 men in...survey is designed to estimate the prevalence of symptoms of urological disorders in a multi-ethnic, community-based sample of adults aged 30−79 years
The Best Estimated Trajectory Analysis for Pad Abort One
NASA Technical Reports Server (NTRS)
Kutty, Prasad; Noonan, Meghan; Karlgaard, Christopher; Beck, Roger
2011-01-01
I. Best Estimated Trajectory (BET) objective: a) Produce reconstructed trajectory of the PA-1 flight to understand vehicle dynamics and aid other post flight analyses. b) Leverage all measurement sources taken of vehicle during flight to produce the most accurate estimate of vehicle trajectory. c) Generate trajectory reconstructions of the Crew Module (CM), Launch Abort System (LAS), and Forward Bay Cover (FBC). II. BET analysis was started immediately following the PA-1 mission and was completed in September, 2010 a) Quick look version of BET released 5/25/2010: initial repackaging of SIGI data. b) Preliminary version of BET released 7/6/2010: first blended solution using available sources of external measurements. c) Final version of BET released 9/1/2010: final blended solution using all available sources of data.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ng, J. A.; Booth, J. T.; O’Brien, R. T.
2014-11-01
Purpose: Kilovoltage intrafraction monitoring (KIM) is a real-time 3D tumor monitoring system for cancer radiotherapy. KIM uses the commonly available gantry-mounted x-ray imager as input, making this method potentially more widely available than dedicated real-time 3D tumor monitoring systems. KIM is being piloted in a clinical trial for prostate cancer patients treated with VMAT (NCT01742403). The purpose of this work was to develop clinical process and quality assurance (QA) practices for the clinical implementation of KIM. Methods: Informed by and adapting existing guideline documents from other real-time monitoring systems, KIM-specific QA practices were developed. The following five KIM-specific QA testsmore » were included: (1) static localization accuracy, (2) dynamic localization accuracy, (3) treatment interruption accuracy, (4) latency measurement, and (5) clinical conditions accuracy. Tests (1)–(4) were performed using KIM to measure static and representative patient-derived prostate motion trajectories using a 3D programmable motion stage supporting an anthropomorphic phantom with implanted gold markers to represent the clinical treatment scenario. The threshold for system tolerable latency is <1 s. The tolerances for all other tests are that both the mean and standard deviation of the difference between the programmed trajectory and the measured data are <1 mm. The (5) clinical conditions accuracy test compared the KIM measured positions with those measured by kV/megavoltage (MV) triangulation from five treatment fractions acquired in a previous pilot study. Results: For the (1) static localization, (2) dynamic localization, and (3) treatment interruption accuracy tests, the mean and standard deviation of the difference are <1.0 mm. (4) The measured latency is 350 ms. (5) For the tests with previously acquired patient data, the mean and standard deviation of the difference between KIM and kV/MV triangulation are <1.0 mm. Conclusions: Clinical process and QA practices for the safe clinical implementation of KIM, a novel real-time monitoring system using commonly available equipment, have been developed and implemented for prostate cancer VMAT.« less
Hakama, Matti; Moss, Sue M; Stenman, Ulf-Hakan; Roobol, Monique J; Zappa, Marco; Carlsson, Sigrid; Randazzo, Marco; Nelen, Vera; Hugosson, Jonas
2017-06-01
Objectives To calculate design-corrected estimates of the effect of screening on prostate cancer mortality by centre in the European Randomised Study of Screening for Prostate Cancer (ERSPC). Setting The ERSPC has shown a 21% reduction in prostate cancer mortality in men invited to screening with follow-up truncated at 13 years. Centres either used pre-consent randomisation (effectiveness design) or post-consent randomisation (efficacy design). Methods In six centres (three effectiveness design, three efficacy design) with follow-up until the end of 2010, or maximum 13 years, the effect of screening was estimated as both effectiveness (mortality reduction in the target population) and efficacy (reduction in those actually screened). Results The overall crude prostate cancer mortality risk ratio in the intervention arm vs control arm for the six centres was 0.79 ranging from a 14% increase to a 38% reduction. The risk ratio was 0.85 in centres with effectiveness design and 0.73 in those with efficacy design. After correcting for design, overall efficacy was 27%, 24% in pre-consent and 29% in post-consent centres, ranging between a 12% increase and a 52% reduction. Conclusion The estimated overall effect of screening in attenders (efficacy) was a 27% reduction in prostate cancer mortality at 13 years' follow-up. The variation in efficacy between centres was greater than the range in risk ratio without correction for design. The centre-specific variation in the mortality reduction could not be accounted for by the randomisation method.
Sun, Yu; Reynolds, Hayley M; Wraith, Darren; Williams, Scott; Finnegan, Mary E; Mitchell, Catherine; Murphy, Declan; Haworth, Annette
2018-04-26
There are currently no methods to estimate cell density in the prostate. This study aimed to develop predictive models to estimate prostate cell density from multiparametric magnetic resonance imaging (mpMRI) data at a voxel level using machine learning techniques. In vivo mpMRI data were collected from 30 patients before radical prostatectomy. Sequences included T2-weighted imaging, diffusion-weighted imaging and dynamic contrast-enhanced imaging. Ground truth cell density maps were computed from histology and co-registered with mpMRI. Feature extraction and selection were performed on mpMRI data. Final models were fitted using three regression algorithms including multivariate adaptive regression spline (MARS), polynomial regression (PR) and generalised additive model (GAM). Model parameters were optimised using leave-one-out cross-validation on the training data and model performance was evaluated on test data using root mean square error (RMSE) measurements. Predictive models to estimate voxel-wise prostate cell density were successfully trained and tested using the three algorithms. The best model (GAM) achieved a RMSE of 1.06 (± 0.06) × 10 3 cells/mm 2 and a relative deviation of 13.3 ± 0.8%. Prostate cell density can be quantitatively estimated non-invasively from mpMRI data using high-quality co-registered data at a voxel level. These cell density predictions could be used for tissue classification, treatment response evaluation and personalised radiotherapy.
Gupta, Manoj; Choudhury, Partha Sarathi; Rawal, Sudhir; Goel, Harish Chandra; Singh, Amitabh; Talwar, Vineet; Sahoo, Saroj Kumar
2017-01-01
Current imaging modalities for prostate cancer (PC) had limitations for risk stratification and staging. Magnetic resonance imaging (MRI) frequently underestimated lymphatic metastasis while bone scintigraphy often had diagnostic dilemmas. Prostatic specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET/CT) has been remarkable in diagnosing PC recurrence and staging. We hypothesized it can become one-stop-shop for initial risk stratification and staging. Ninety seven PSMA PET-CT studies were re analysed for tumor node metastases (TNM) staging and risk stratification of lymphatic and distant metastases proportion. The histopathology of 23/97 patients was available as gold standard. Chi-square test was used for proportion comparison. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), over-estimation, under-estimation and correct-estimation of T and N stages were calculated. Cohen's kappa coefficient (k) was derived for inter-rater agreement. Lymphic or distant metastases detection on PSMA PET/CT increased significantly with increase in risk category. PSMA PET/CT sensitivity, specificity, PPV and NPV for extra prostatic extension (EPE), seminal vesicle invasion (SVI) and lymphatic metastases were 63.16%, 100%, 100%, 36.36% & 55%, 100%, 100%, 25% and 65.62%, 99.31%, 87.50%, 97.53%, respectively. Cohen's kappa coefficient showed substantial agreement between PSMA PET/CT and histopathological lymphic metastases (κ 0.734) however, it was just in fair agreement (κ 0.277) with T stage. PSMA PET/CT over-estimated, under-estimated and correct-estimated T and N stages in 8.71%, 39.13%, 52.17% and 8.71%, 4.35%, 86.96% cases, respectively. We found that PSMA PET/CT has potential for initial risk stratifications with reasonable correct estimation for N stage. However, it can underestimate T stage. Hence, we suggest that PSMA PET/CT should be used for staging and initial risk stratification of PC as one-stop-shop with regional MRI in surgically resectable cases.
Prostate Cancer Stem-Like Cells | Center for Cancer Research
Prostate cancer is the third leading cause of cancer-related death among men, killing an estimated 27,000 men each year in the United States. Men with advanced prostate cancer often become resistant to conventional therapies. Many researchers speculate that the emergence of resistance is due to the presence of cancer stem cells, which are believed to be a small subpopulation
Brenner, David J; Martinez, Alvaro A; Edmundson, Gregory K; Mitchell, Christina; Thames, Howard D; Armour, Elwood P
2002-01-01
A direct approach to the question of whether prostate tumors have an atypically high sensitivity to fractionation (low alpha/beta ratio), more typical of the surrounding late-responding normal tissue. Earlier estimates of alpha/beta for prostate cancer have relied on comparing results from external beam radiotherapy (EBRT) and brachytherapy, an approach with significant pitfalls due to the many differences between the treatments. To circumvent this, we analyze recent data from a single EBRT + high-dose-rate (HDR) brachytherapy protocol, in which the brachytherapy was given in either 2 or 3 implants, and at various doses. For the analysis, standard models of tumor cure based on Poisson statistics were used in conjunction with the linear-quadratic formalism. Biochemical control at 3 years was the clinical endpoint. Patients were matched between the 3 HDR vs. 2 HDR implants by clinical stage, pretreatment prostate-specific antigen (PSA), Gleason score, length of follow-up, and age. The estimated value of alpha/beta from the current analysis of 1.2 Gy (95% CI: 0.03, 4.1 Gy) is consistent with previous estimates for prostate tumor control. This alpha/beta value is considerably less than typical values for tumors (> or =8 Gy), and more comparable to values in surrounding late-responding normal tissues. This analysis provides strong supporting evidence that alpha/beta values for prostate tumor control are atypically low, as indicated by previous analyses and radiobiological considerations. If true, hypofractionation or HDR regimens for prostate radiotherapy (with appropriate doses) should produce tumor control and late sequelae that are at least as good or even better than currently achieved, with the added possibility that early sequelae may be reduced.
Redman, Mary W.; Tangen, Catherine M.; Goodman, Phyllis J.; Parnes, Howard; Ford, Leslie G.; Lucia, M. Scott; Coltman, Charles A.; Thompson, Ian M.
2010-01-01
The Prostate Cancer Prevention Trial found that seven years of administration of finasteride reduced the risk of prostate cancer by 25% but with an apparent increased risk of high grade disease. Subsequent analyses found that finasteride affects cancer detection and improves accuracy of tumor grading at biopsy. We herein estimate the impact of finasteride on the risk of overall and high grade prostate cancer, accounting for these biases. Study endpoints (biopsy-proven cancer or a 7-year end-of-study biopsy) were available in 10,182 of 15,990 subjects assessable for 7-year status and grading information from 500 subjects diagnosed with cancer who underwent radical prostatectomy. Prostate cancer was observed in 22.9% (4.8% with high grade) in the placebo group versus 16.6% (5.8% with high grade) in the finasteride group. In this bias-adjusted analysis, the estimated rates are 21.1% (4.2%) and 14.7% (4.8%), respectively, a 30% risk reduction in prostate cancer (RR =0.70 (95% confidence interval (CI) =0.64-0.76, p<0.0001) and a non-significant 14% increase in high grade cancer (RR=1.14 (95% CI = (0.96-1.35), p=0.12) with finasteride. Incorporating the prostatectomy data, estimated rates of high grade cancers are 8.2% (placebo) versus 6.0% (finasteride), a 27% risk reduction (RR = 0.73 (95% CI=0.56-0.96, p=0.02)) with finasteride. While the observed risk of high grade disease is greater with finasteride, this appears to be through facilitated diagnosis, primarily due to increased biopsy sensitivity. Men undergoing regular prostate cancer screening or who express an interest in cancer prevention should be informed of this prevention opportunity. PMID:19138953
NASA Astrophysics Data System (ADS)
Xu, Robert S.; Michailovich, Oleg V.; Solovey, Igor; Salama, Magdy M. A.
2010-03-01
Prostate specific antigen density is an established parameter for indicating the likelihood of prostate cancer. To this end, the size and volume of the gland have become pivotal quantities used by clinicians during the standard cancer screening process. As an alternative to manual palpation, an increasing number of volume estimation methods are based on the imagery data of the prostate. The necessity to process large volumes of such data requires automatic segmentation algorithms, which can accurately and reliably identify the true prostate region. In particular, transrectal ultrasound (TRUS) imaging has become a standard means of assessing the prostate due to its safe nature and high benefit-to-cost ratio. Unfortunately, modern TRUS images are still plagued by many ultrasound imaging artifacts such as speckle noise and shadowing, which results in relatively low contrast and reduced SNR of the acquired images. Consequently, many modern segmentation methods incorporate prior knowledge about the prostate geometry to enhance traditional segmentation techniques. In this paper, a novel approach to the problem of TRUS segmentation, particularly the definition of the prostate shape prior, is presented. The proposed approach is based on the concept of distribution tracking, which provides a unified framework for tracking both photometric and morphological features of the prostate. In particular, the tracking of morphological features defines a novel type of "weak" shape priors. The latter acts as a regularization force, which minimally bias the segmentation procedure, while rendering the final estimate stable and robust. The value of the proposed methodology is demonstrated in a series of experiments.
Non-Rigid Structure Estimation in Trajectory Space from Monocular Vision
Wang, Yaming; Tong, Lingling; Jiang, Mingfeng; Zheng, Junbao
2015-01-01
In this paper, the problem of non-rigid structure estimation in trajectory space from monocular vision is investigated. Similar to the Point Trajectory Approach (PTA), based on characteristic points’ trajectories described by a predefined Discrete Cosine Transform (DCT) basis, the structure matrix was also calculated by using a factorization method. To further optimize the non-rigid structure estimation from monocular vision, the rank minimization problem about structure matrix is proposed to implement the non-rigid structure estimation by introducing the basic low-rank condition. Moreover, the Accelerated Proximal Gradient (APG) algorithm is proposed to solve the rank minimization problem, and the initial structure matrix calculated by the PTA method is optimized. The APG algorithm can converge to efficient solutions quickly and lessen the reconstruction error obviously. The reconstruction results of real image sequences indicate that the proposed approach runs reliably, and effectively improves the accuracy of non-rigid structure estimation from monocular vision. PMID:26473863
Ginsburg, Shoshana B; Taimen, Pekka; Merisaari, Harri; Vainio, Paula; Boström, Peter J; Aronen, Hannu J; Jambor, Ivan; Madabhushi, Anant
2016-12-01
To develop and evaluate a prostate-based method (PBM) for estimating pharmacokinetic parameters on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) by leveraging inherent differences in pharmacokinetic characteristics between the peripheral zone (PZ) and transition zone (TZ). This retrospective study, approved by the Institutional Review Board, included 40 patients who underwent a multiparametric 3T MRI examination and subsequent radical prostatectomy. A two-step PBM for estimating pharmacokinetic parameters exploited the inherent differences in pharmacokinetic characteristics associated with the TZ and PZ. First, the reference region model was implemented to estimate ratios of K trans between normal TZ and PZ. Subsequently, the reference region model was leveraged again to estimate values for K trans and v e for every prostate voxel. The parameters of PBM were compared with those estimated using an arterial input function (AIF) derived from the femoral arteries. The ability of the parameters to differentiate prostate cancer (PCa) from benign tissue was evaluated on a voxel and lesion level. Additionally, the effect of temporal downsampling of the DCE MRI data was assessed. Significant differences (P < 0.05) in PBM K trans between PCa lesions and benign tissue were found in 26/27 patients with TZ lesions and in 33/38 patients with PZ lesions; significant differences in AIF-based K trans occurred in 26/27 and 30/38 patients, respectively. The 75 th and 100 th percentiles of K trans and v e estimated using PBM positively correlated with lesion size (P < 0.05). Pharmacokinetic parameters estimated via PBM outperformed AIF-based parameters in PCa detection. J. Magn. Reson. Imaging 2016;44:1405-1414. © 2016 International Society for Magnetic Resonance in Medicine.
Ginsburg, Shoshana B.; Taimen, Pekka; Merisaari, Harri; Vainio, Paula; Boström, Peter J.; Aronen, Hannu J.; Jambor, Ivan; Madabhushi, Anant
2017-01-01
Purpose To develop and evaluate a prostate-based method (PBM) for estimating pharmacokinetic parameters on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) by leveraging inherent differences in pharmacokinetic characteristics between the peripheral zone (PZ) and transition zone (TZ). Materials and Methods This retrospective study, approved by the Institutional Review Board, included 40 patients who underwent a multiparametric 3T MRI examination and subsequent radical prostatectomy. A two-step PBM for estimating pharmacokinetic parameters exploited the inherent differences in pharmacokinetic characteristics associated with the TZ and PZ. First, the reference region model was implemented to estimate ratios of Ktrans between normal TZ and PZ. Subsequently, the reference region model was leveraged again to estimate values for Ktrans and ve for every prostate voxel. The parameters of PBM were compared with those estimated using an arterial input function (AIF) derived from the femoral arteries. The ability of the parameters to differentiate prostate cancer (PCa) from benign tissue was evaluated on a voxel and lesion level. Additionally, the effect of temporal downsampling of the DCE MRI data was assessed. Results Significant differences (P < 0.05) in PBM Ktrans between PCa lesions and benign tissue were found in 26/27 patients with TZ lesions and in 33/38 patients with PZ lesions; significant differences in AIF-based Ktrans occurred in 26/27 and 30/38 patients, respectively. The 75th and 100th percentiles of Ktrans and ve estimated using PBM positively correlated with lesion size (P < 0.05). Conclusion Pharmacokinetic parameters estimated via PBM outperformed AIF-based parameters in PCa detection. PMID:27285161
NASA Technical Reports Server (NTRS)
Kelly, G. M.; Mcconnell, J. G.; Findlay, J. T.; Heck, M. L.; Henry, M. W.
1984-01-01
The STS-11 (41-B) postflight data processing is completed and the results published. The final reconstructed entry trajectory is presented. The various atmospheric sources available for this flight are discussed. Aerodynamic Best Estimate of Trajectory BET generation and plots from this file are presented. A definition of the major maneuvers effected is given. Physical constants, including spacecraft mass properties; final residuals from the reconstruction process; trajectory parameter listings; and an archival section are included.
Real-time individual predictions of prostate cancer recurrence using joint models
Taylor, Jeremy M. G.; Park, Yongseok; Ankerst, Donna P.; Proust-Lima, Cecile; Williams, Scott; Kestin, Larry; Bae, Kyoungwha; Pickles, Tom; Sandler, Howard
2012-01-01
Summary Patients who were previously treated for prostate cancer with radiation therapy are monitored at regular intervals using a laboratory test called Prostate Specific Antigen (PSA). If the value of the PSA test starts to rise, this is an indication that the prostate cancer is more likely to recur, and the patient may wish to initiate new treatments. Such patients could be helped in making medical decisions by an accurate estimate of the probability of recurrence of the cancer in the next few years. In this paper, we describe the methodology for giving the probability of recurrence for a new patient, as implemented on a web-based calculator. The methods use a joint longitudinal survival model. The model is developed on a training dataset of 2,386 patients and tested on a dataset of 846 patients. Bayesian estimation methods are used with one Markov chain Monte Carlo (MCMC) algorithm developed for estimation of the parameters from the training dataset and a second quick MCMC developed for prediction of the risk of recurrence that uses the longitudinal PSA measures from a new patient. PMID:23379600
Is prostate cancer different in black men? Answers from three natural history models
Tsodikov, Alex; Gulati, Roman; de Carvalho, Tiago M.; Heijnsdijk, Eveline A. M.; Hunter-Merrill, Rachel A.; Mariotto, Angela B.; de Koning, Harry J.; Etzioni, Ruth
2017-01-01
Background Black men in the US have substantially higher prostate cancer incidence rates than the general population. The extent to which the incidence disparity is due to prostate cancer being more prevalent, more aggressive, and/or more frequently diagnosed in black men is unknown. Methods We estimated three independently developed models of prostate cancer natural history in black men and in the general population using an updated reconstruction of PSA screening, based on the National Health Interview Survey in 2005, and prostate cancer incidence from the Surveillance, Epidemiology, and End Results program in 1975–2000. Using the estimated models, we compared prostate cancer natural history in black men and in the general population. Results The models projected that 30–43% (range across models) of black men develop preclinical prostate cancer by age 85 years, a risk that is (relatively) 28–56% higher than in the general population. Among men who have had preclinical disease onset, black men have a similar risk of diagnosis (35–49%) compared with the general population (32–44%), but their risk of progression to metastatic disease by the time of diagnosis is 44–75% higher than in the general population. Conclusions Prostate cancer incidence patterns implicate higher incidence of preclinical disease and higher risk of metastatic progression among black men. The findings suggest screening black men earlier than white men and support further research into the benefit-harm tradeoffs of more aggressive screening policies for black men. PMID:28436011
FitzGerald, Liesel M.; Kwon, Erika M.; Koopmeiners, Joseph S.; Salinas, Claudia A.; Stanford, Janet L.; Ostrander, Elaine A.
2009-01-01
Purpose Two recent genome-wide association studies have highlighted several SNPs purported to be associated with prostate cancer risk. We investigated the significance of these SNPs in a population-based study of Caucasian men, testing the effects of each SNP in relation to family history of prostate cancer and clinicopathological features of disease. Experimental Design We genotyped 13 SNPs in 1,308 prostate cancer patients and 1,267 unaffected controls frequency matched to cases by five-year age groups. The association of each SNP with disease risk and stratified by family history of prostate cancer and clinicopathological features of disease was calculated using logistic and polytomous regression. Results These results confirm the importance of multiple previously reported SNPs in relation to prostate cancer susceptibility; 11 of the 13 SNPs were significantly associated with risk of developing prostate cancer. However, none of the SNP associations were of comparable magnitude to that associated with having a first-degree family history of the disease. Risk estimates associated with SNPs rs4242382 and rs2735839 varied by family history, while risk estimates for rs10993994 and rs5945619 varied by Gleason score. Conclusions Our results confirm that several recently identified SNPs are associated with prostate cancer risk; however the variant alleles only confer a low to moderate relative risk of disease and are generally not associated with more aggressive disease features. PMID:19366831
Ma, Qingtong; Qi, Can; Tie, Chong; Guo, Zhanjun
2013-11-10
Many studies have reported the role of xeroderma pigmentosum group D (XPD) with prostate cancer risk, but the results remained controversial. To derive a more precise estimation of the relationship, a meta-analysis was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between XPD Asp312Asn and Lys751Gln polymorphisms and prostate cancer risk. A total of 8 studies including 2620 cases and 3225 controls described Asp312Asn genotypes, among which 10 articles involving 3230 cases and 3582 controls described Lys751Gln genotypes and were also involved in this meta-analysis. When all the eligible studies were pooled into this meta-analysis, a significant association between prostate cancer risk and XPD Asp312Asn polymorphism was found. For Asp312Asn polymorphism, in the stratified analysis by ethnicity and source of controls, prostate cancer risk was observed in co-dominant, dominant and recessive models, while no evidence of any associations of XPD Lys751Gln polymorphism with prostate cancer was found in the overall or subgroup analyses. Our meta-analysis supports that the XPD Asp312Asn polymorphism contributed to the risk of prostate cancer from currently available evidence. However, a study with a larger sample size is needed to further evaluate gene-environment interaction on XPD Asp312Asn and Lys751Gln polymorphisms and prostate cancer risk. © 2013.
Udeh, Emeka I; Nnabugwu, Ikenna I; Ozoemena, Francis O; Ugwumba, Fred O; Aderibigbe, Adesina S O; Ohayi, Samuel R; Echetabu, Kevin N
2016-06-29
This study aims to estimate the prostate-specific antigen density (PSAD) cutoff level for detecting prostate cancer (CAP) in Nigerian men with "grey zone PSA" (4-10 ng/ml) and normal digital rectal examination findings. We addressed this research question: Is the international PSAD cutoff of 0.15 ideal for detecting CAP in our symptomatic patients with "grey zone PSA?" To estimate the prostate-specific antigen density (PSAD) cutoff level for detecting CAP in Nigerian men with "grey zone PSA" (4-10 ng/ml) and normal digital rectal examination findings. Prospective. A tertiary medical center in Enugu, Nigeria. Two hundred and fifty-four men with either benign prostatic hyperplasia (BPH) or CAP were recruited. Patients with PSA above 4 ng/ml or abnormal digital rectal examination or hypoechoic lesion in the prostate were biopsied. PSAD and histology report of BPH or CAP. Ninety-seven patients had CAP while 157 had benign prostatic hyperplasia (BPH). Seventy-two patients had their serum PSA value within the range of 4.0 and 10 ng/ml. PSAD cutoff level to detect CAP was 0.04 (sensitivity 95.88 %; specificity 28.7 %). The PSAD cutoff level generated for Nigerian men in this study is 0.04 which is relatively different from international consensus. This PSAD cutoff level has a positive correlation with histology and could detect patients with CAP who have "grey zone PSA."
Carleton, Amanda J; Sievenpiper, John L; de Souza, Russell; McKeown-Eyssen, Gail; Jenkins, David J A
2013-01-01
Objective α-Linolenic acid (ALA) is considered to be a cardioprotective nutrient; however, some epidemiological studies have suggested that dietary ALA intake increases the risk of prostate cancer. The main objective was to conduct a systematic review and meta-analysis of case–control and prospective studies investigating the association between dietary ALA intake and prostate cancer risk. Design A systematic review and meta-analysis were conducted by searching MEDLINE and EMBASE for relevant prospective and case–control studies. Included studies We included all prospective cohort, case–control, nested case-cohort and nested case–control studies that investigated the effect of dietary ALA intake on the incidence (or diagnosis) of prostate cancer and provided relative risk (RR), HR or OR estimates. Primary outcome measure Data were pooled using the generic inverse variance method with a random effects model from studies that compared the highest ALA quantile with the lowest ALA quantile. Risk estimates were expressed as RR with 95% CIs. Heterogeneity was assessed by χ2 and quantified by I2. Results Data from five prospective and seven case–control studies were pooled. The overall RR estimate showed ALA intake to be positively but non-significantly associated with prostate cancer risk (1.08 (0.90 to 1.29), p=0.40; I2=85%), but the interpretation was complicated by evidence of heterogeneity not explained by study design. A weak, non-significant protective effect of ALA intake on prostate cancer risk in the prospective studies became significant (0.91 (0.83 to 0.99), p=0.02) without evidence of heterogeneity (I2=8%, p=0.35) on removal of one study during sensitivity analyses. Conclusions This analysis failed to confirm an association between dietary ALA intake and prostate cancer risk. Larger and longer observational and interventional studies are needed to define the role of ALA and prostate cancer. PMID:23674441
Reconciling the effects of screening on prostate cancer mortality in the ERSPC and PLCO trials
Tsodikov, Alex; Gulati, Roman; Heijnsdijk, Eveline AM; Pinsky, Paul F; Moss, Sue M; Qiu, Sheng; de Carvalho, Tiago M; Hugosson, Jonas; Berg, Christine D; Auvinen, Anssi; Andriole, Gerald L; Roobol, Monique J; Crawford, E David; Nelen, Vera; Kwiatkowski, Maciej; Zappa, Marco; Luján, Marcos; Villers, Arnauld; Feuer, Eric J; de Koning, Harry J; Mariotto, Angela B; Etzioni, Ruth
2017-01-01
Background The European Randomized Study of Screening for Prostate Cancer (ERSPC) found screening reduced prostate cancer (PC) mortality, but the Prostate, Lung, Colorectal, and Ovarian trial (PLCO) found no reduction. Objective To evaluate whether effects of screening on PC mortality relative to no screening differed between the ERSPC and PLCO. Design Cox regression of PC death in each trial arm adjusted for age and trial, and extended analyses that accounted for increased incidence due to screening and diagnostic workup on each arm via mean lead times (MLTs). MLTs were estimated empirically and using analytic or microsimulation models. Setting Randomized controlled trials in Europe and the US. Participants Men aged 55–69 (ERSPC) or 55–74 (PLCO) at randomization. Intervention Prostate cancer screening. Measurements PC incidence and survival from randomization; PC incidence in the US before screening began. Results Estimated MLTs were similar in the ERSPC and PLCO intervention arms but were longer in the PLCO control arm than the ERSPC control arm. Extended analyses found no evidence that effects of screening differed between trials (P=0.37–0.47, range across MLT estimation approaches) but strong evidence that benefit increased with MLT (P=0.0027–0.0032). Screening was estimated to confer a 7–9% reduction in PC death per year of MLT. This translated into an estimated 25–31% and 27–32% lower risk of PC death under screening as performed in the ERSPC and PLCO intervention arms, respectively, relative to no screening. Limitations MLT is a simple metric of screening and diagnostic workup. Conclusion After accounting for differences in implementation and settings, the ERSPC and PLCO provide compatible evidence that screening reduces PC mortality. PMID:28869989
NASA Astrophysics Data System (ADS)
Shinnaka, Shinji; Sano, Kousuke
This paper presents a new unified analysis of estimate errors by model-matching phase-estimation methods such as rotor-flux state-observers, back EMF state-observers, and back EMF disturbance-observers, for sensorless drive of permanent-magnet synchronous motors. Analytical solutions about estimate errors, whose validity is confirmed by numerical experiments, are rich in universality and applicability. As an example of universality and applicability, a new trajectory-oriented vector control method is proposed, which can realize directly quasi-optimal strategy minimizing total losses with no additional computational loads by simply orienting one of vector-control coordinates to the associated quasi-optimal trajectory. The coordinate orientation rule, which is analytically derived, is surprisingly simple. Consequently the trajectory-oriented vector control method can be applied to a number of conventional vector control systems using one of the model-matching phase-estimation methods.
Song, Shu-qi; Zhang, Ya-qiang
2009-12-01
The etiology, pathogenesis, and diagnostic criteria of chronic prostatitis were reviewed in this article. Based on clinical practice, the authors systematically discussed the thoughts and methods for the treatment of chronic prostatitis by integrated traditional Chinese and Western medicine. Meanwhile, advice on disputed problems in clinical study of prostatits were given, such as curative effect estimation value of the number of leukocytes in expressed prostatic secretion (EPS) and bacterial culture in EPS, the opportunity and treatment course of antibiotics, National Institutes of Health chronic prostatitis symptom index, classification of syndromes of traditional Chinese medicine (TCM), TCM symptom score, and clinical study period.
Dodani, Sunjay S; Lu, Charles W; Aldridge, J Wayne; Chou, Kelvin L; Patil, Parag G
2018-06-01
Accurate electrode placement is critical to the success of deep brain stimulation (DBS) surgery. Suboptimal targeting may arise from poor initial target localization, frame-based targeting error, or intraoperative brain shift. These uncertainties can make DBS surgery challenging. To develop a computerized system to guide subthalamic nucleus (STN) DBS electrode localization and to estimate the trajectory of intraoperative microelectrode recording (MER) on magnetic resonance (MR) images algorithmically during DBS surgery. Our method is based upon the relationship between the high-frequency band (HFB; 500-2000 Hz) signal from MER and voxel intensity on MR images. The HFB profile along an MER trajectory recorded during surgery is compared to voxel intensity profiles along many potential trajectories in the region of the surgically planned trajectory. From these comparisons of HFB recordings and potential trajectories, an estimate of the MER trajectory is calculated. This calculated trajectory is then compared to actual trajectory, as estimated by postoperative high-resolution computed tomography. We compared 20 planned, calculated, and actual trajectories in 13 patients who underwent STN DBS surgery. Targeting errors for our calculated trajectories (2.33 mm ± 0.2 mm) were significantly less than errors for surgically planned trajectories (2.83 mm ± 0.2 mm; P = .01), improving targeting prediction in 70% of individual cases (14/20). Moreover, in 4 of 4 initial MER trajectories that missed the STN, our method correctly indicated the required direction of targeting adjustment for the DBS lead to intersect the STN. A computer-based algorithm simultaneously utilizing MER and MR information potentially eases electrode localization during STN DBS surgery.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Worm, Esben S., E-mail: esbeworm@rm.dk; Department of Medical Physics, Aarhus University Hospital, Aarhus; Hoyer, Morten
2012-05-01
Purpose: To develop and evaluate accurate and objective on-line patient setup based on a novel semiautomatic technique in which three-dimensional marker trajectories were estimated from two-dimensional cone-beam computed tomography (CBCT) projections. Methods and Materials: Seven treatment courses of stereotactic body radiotherapy for liver tumors were delivered in 21 fractions in total to 6 patients by a linear accelerator. Each patient had two to three gold markers implanted close to the tumors. Before treatment, a CBCT scan with approximately 675 two-dimensional projections was acquired during a full gantry rotation. The marker positions were segmented in each projection. From this, the three-dimensionalmore » marker trajectories were estimated using a probability based method. The required couch shifts for patient setup were calculated from the mean marker positions along the trajectories. A motion phantom moving with known tumor trajectories was used to examine the accuracy of the method. Trajectory-based setup was retrospectively used off-line for the first five treatment courses (15 fractions) and on-line for the last two treatment courses (6 fractions). Automatic marker segmentation was compared with manual segmentation. The trajectory-based setup was compared with setup based on conventional CBCT guidance on the markers (first 15 fractions). Results: Phantom measurements showed that trajectory-based estimation of the mean marker position was accurate within 0.3 mm. The on-line trajectory-based patient setup was performed within approximately 5 minutes. The automatic marker segmentation agreed with manual segmentation within 0.36 {+-} 0.50 pixels (mean {+-} SD; pixel size, 0.26 mm in isocenter). The accuracy of conventional volumetric CBCT guidance was compromised by motion smearing ({<=}21 mm) that induced an absolute three-dimensional setup error of 1.6 {+-} 0.9 mm (maximum, 3.2) relative to trajectory-based setup. Conclusions: The first on-line clinical use of trajectory estimation from CBCT projections for precise setup in stereotactic body radiotherapy was demonstrated. Uncertainty in the conventional CBCT-based setup procedure was eliminated with the new method.« less
Prostate cancer and inflammation: the evidence
Sfanos, Karen S; De Marzo, Angelo M
2014-01-01
Chronic inflammation is now known to contribute to several forms of human cancer, with an estimated 20% of adult cancers attributable to chronic inflammatory conditions caused by infectious agents, chronic noninfectious inflammatory diseases and / or other environmental factors. Indeed, chronic inflammation is now regarded as an ‘enabling characteristic’ of human cancer. The aim of this review is to summarize the current literature on the evidence for a role for chronic inflammation in prostate cancer aetiology, with a specific focus on recent advances regarding the following: (i) potential stimuli for prostatic inflammation; (ii) prostate cancer immunobiology; (iii) inflammatory pathways and cytokines in prostate cancer risk and development; (iv) proliferative inflammatory atrophy (PIA) as a risk factor lesion to prostate cancer development; and (v) the role of nutritional or other antiinflammatory compounds in reducing prostate cancer risk. PMID:22212087
SU-F-T-40: Can CBCT Images Be Used for Volume Studies of Prostate Seed Implants for Boost Treatment?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, H; Lee, S; Diwanji, T
Purpose: In our clinic, the planning CT is used for definitive and boost low-dose-rate (LDR) brachytherapy treatments to determine the ultrasound volume in the operating room (OR) at the time of the implant. While the CT overestimation of OR volume is known, a larger estimation discrepancy has been observed for boost treatments. A possible reason is the prostate size reduction during EBRT for boost patients. Since cone-beam CT (CBCT) is often used as routine imaging guidance of EBRT, this prostate volume change may be captured. This study investigates if CBCT taken during EBRT includes the volume change information and thereforemore » beats CT in estimating the prostate OR volumes. Methods: 9 prostate patients treated with EBRT (45Gy in 1.8Gy per fractions to the whole pelvis) and I-125 seed implants (108Gy) were involved in this study. During EBRT, CBCT image guidance was performed on a weekly basis. For each patient, the prostate volumes on the first and the last available CBCT images were manually contoured by a physician. These volumes were then compared to each other and with the contoured volumes from the planning CT and from the ultrasound images in the OR. Results: The first and the last CBCT images did not show significant prostate volume change. Their average +/− standard deviation of prostate volumes were 24.4cc+/−14.6cc and 29.9cc+/−16.1cc, respectively (T-test p=0.68). The ratio of the OR volume to the last CBCT (0.71+/−0.21) was not significantly different from the ratio of OR volumes to the planning CT (0.61+/−0.13) (p=0.25). Conclusion: In this study, CBCT does not show significant prostate volume changes during EBRT. CBCT and CT volumes are quite consistent and no improvement of volume estimation using CBCT is observed. The advantage of CBCT as a replacement of CT for volume study of boost LDR brachytherapy is limited.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pursley, Jennifer; Risholm, Petter; Fedorov, Andriy
2012-11-15
Purpose: This study introduces a probabilistic nonrigid registration method for use in image-guided prostate brachytherapy. Intraoperative imaging for prostate procedures, usually transrectal ultrasound (TRUS), is typically inferior to diagnostic-quality imaging of the pelvis such as endorectal magnetic resonance imaging (MRI). MR images contain superior detail of the prostate boundaries and provide substructure features not otherwise visible. Previous efforts to register diagnostic prostate images with the intraoperative coordinate system have been deterministic and did not offer a measure of the registration uncertainty. The authors developed a Bayesian registration method to estimate the posterior distribution on deformations and provide a case-specific measuremore » of the associated registration uncertainty. Methods: The authors adapted a biomechanical-based probabilistic nonrigid method to register diagnostic to intraoperative images by aligning a physician's segmentations of the prostate in the two images. The posterior distribution was characterized with a Markov Chain Monte Carlo method; the maximum a posteriori deformation and the associated uncertainty were estimated from the collection of deformation samples drawn from the posterior distribution. The authors validated the registration method using a dataset created from ten patients with MRI-guided prostate biopsies who had both diagnostic and intraprocedural 3 Tesla MRI scans. The accuracy and precision of the estimated posterior distribution on deformations were evaluated from two predictive distance distributions: between the deformed central zone-peripheral zone (CZ-PZ) interface and the physician-labeled interface, and based on physician-defined landmarks. Geometric margins on the registration of the prostate's peripheral zone were determined from the posterior predictive distance to the CZ-PZ interface separately for the base, mid-gland, and apical regions of the prostate. Results: The authors observed variation in the shape and volume of the segmented prostate in diagnostic and intraprocedural images. The probabilistic method allowed us to convey registration results in terms of posterior distributions, with the dispersion providing a patient-specific estimate of the registration uncertainty. The median of the predictive distance distribution between the deformed prostate boundary and the segmented boundary was Less-Than-Or-Slanted-Equal-To 3 mm (95th percentiles within {+-}4 mm) for all ten patients. The accuracy and precision of the internal deformation was evaluated by comparing the posterior predictive distance distribution for the CZ-PZ interface for each patient, with the median distance ranging from -0.6 to 2.4 mm. Posterior predictive distances between naturally occurring landmarks showed registration errors of Less-Than-Or-Slanted-Equal-To 5 mm in any direction. The uncertainty was not a global measure, but instead was local and varied throughout the registration region. Registration uncertainties were largest in the apical region of the prostate. Conclusions: Using a Bayesian nonrigid registration method, the authors determined the posterior distribution on deformations between diagnostic and intraprocedural MR images and quantified the uncertainty in the registration results. The feasibility of this approach was tested and results were positive. The probabilistic framework allows us to evaluate both patient-specific and location-specific estimates of the uncertainty in the registration result. Although the framework was tested on MR-guided procedures, the preliminary results suggest that it may be applied to TRUS-guided procedures as well, where the addition of diagnostic MR information may have a larger impact on target definition and clinical guidance.« less
Pursley, Jennifer; Risholm, Petter; Fedorov, Andriy; Tuncali, Kemal; Fennessy, Fiona M.; Wells, William M.; Tempany, Clare M.; Cormack, Robert A.
2012-01-01
Purpose: This study introduces a probabilistic nonrigid registration method for use in image-guided prostate brachytherapy. Intraoperative imaging for prostate procedures, usually transrectal ultrasound (TRUS), is typically inferior to diagnostic-quality imaging of the pelvis such as endorectal magnetic resonance imaging (MRI). MR images contain superior detail of the prostate boundaries and provide substructure features not otherwise visible. Previous efforts to register diagnostic prostate images with the intraoperative coordinate system have been deterministic and did not offer a measure of the registration uncertainty. The authors developed a Bayesian registration method to estimate the posterior distribution on deformations and provide a case-specific measure of the associated registration uncertainty. Methods: The authors adapted a biomechanical-based probabilistic nonrigid method to register diagnostic to intraoperative images by aligning a physician's segmentations of the prostate in the two images. The posterior distribution was characterized with a Markov Chain Monte Carlo method; the maximum a posteriori deformation and the associated uncertainty were estimated from the collection of deformation samples drawn from the posterior distribution. The authors validated the registration method using a dataset created from ten patients with MRI-guided prostate biopsies who had both diagnostic and intraprocedural 3 Tesla MRI scans. The accuracy and precision of the estimated posterior distribution on deformations were evaluated from two predictive distance distributions: between the deformed central zone-peripheral zone (CZ-PZ) interface and the physician-labeled interface, and based on physician-defined landmarks. Geometric margins on the registration of the prostate's peripheral zone were determined from the posterior predictive distance to the CZ-PZ interface separately for the base, mid-gland, and apical regions of the prostate. Results: The authors observed variation in the shape and volume of the segmented prostate in diagnostic and intraprocedural images. The probabilistic method allowed us to convey registration results in terms of posterior distributions, with the dispersion providing a patient-specific estimate of the registration uncertainty. The median of the predictive distance distribution between the deformed prostate boundary and the segmented boundary was ⩽3 mm (95th percentiles within ±4 mm) for all ten patients. The accuracy and precision of the internal deformation was evaluated by comparing the posterior predictive distance distribution for the CZ-PZ interface for each patient, with the median distance ranging from −0.6 to 2.4 mm. Posterior predictive distances between naturally occurring landmarks showed registration errors of ⩽5 mm in any direction. The uncertainty was not a global measure, but instead was local and varied throughout the registration region. Registration uncertainties were largest in the apical region of the prostate. Conclusions: Using a Bayesian nonrigid registration method, the authors determined the posterior distribution on deformations between diagnostic and intraprocedural MR images and quantified the uncertainty in the registration results. The feasibility of this approach was tested and results were positive. The probabilistic framework allows us to evaluate both patient-specific and location-specific estimates of the uncertainty in the registration result. Although the framework was tested on MR-guided procedures, the preliminary results suggest that it may be applied to TRUS-guided procedures as well, where the addition of diagnostic MR information may have a larger impact on target definition and clinical guidance. PMID:23127078
2010-01-01
Over the past decade, several large epidemiologic investigations of meat intake and prostate cancer have been published. Therefore, a meta-analysis of prospective studies was conducted to estimate potential associations between red or processed meat intake and prostate cancer. Fifteen studies of red meat and 11 studies of processed meat were included in the analyses. High vs. low intake and dose-response analyses were conducted using random effects models to generate summary relative risk estimates (SRRE). No association between high vs. low red meat consumption (SRRE = 1.00, 95% CI: 0.96-1.05) or each 100 g increment of red meat (SRRE = 1.00, 95% CI: 0.95-1.05) and total prostate cancer was observed. Similarly, no association with red meat was observed for advanced prostate cancer (SRRE = 1.01, 95% CI: 0.94-1.09). A weakly elevated summary association between processed meat and total prostate cancer was found (SRRE = 1.05, 95% CI: 0.99-1.12), although heterogeneity was present, the association was attenuated in a sub-group analysis of studies that adjusted for multiple potential confounding factors, and publication bias likely affected the summary effect. In conclusion, the results of this meta-analysis are not supportive of an independent positive association between red or processed meat intake and prostate cancer. PMID:21044319
Quantitative three-dimensional transrectal ultrasound (TRUS) for prostate imaging
NASA Astrophysics Data System (ADS)
Pathak, Sayan D.; Aarnink, Rene G.; de la Rosette, Jean J.; Chalana, Vikram; Wijkstra, Hessel; Haynor, David R.; Debruyne, Frans M. J.; Kim, Yongmin
1998-06-01
With the number of men seeking medical care for prostate diseases rising steadily, the need of a fast and accurate prostate boundary detection and volume estimation tool is being increasingly experienced by the clinicians. Currently, these measurements are made manually, which results in a large examination time. A possible solution is to improve the efficiency by automating the boundary detection and volume estimation process with minimal involvement from the human experts. In this paper, we present an algorithm based on SNAKES to detect the boundaries. Our approach is to selectively enhance the contrast along the edges using an algorithm called sticks and integrate it with a SNAKES model. This integrated algorithm requires an initial curve for each ultrasound image to initiate the boundary detection process. We have used different schemes to generate the curves with a varying degree of automation and evaluated its effects on the algorithm performance. After the boundaries are identified, the prostate volume is calculated using planimetric volumetry. We have tested our algorithm on 6 different prostate volumes and compared the performance against the volumes manually measured by 3 experts. With the increase in the user inputs, the algorithm performance improved as expected. The results demonstrate that given an initial contour reasonably close to the prostate boundaries, the algorithm successfully delineates the prostate boundaries in an image, and the resulting volume measurements are in close agreement with those made by the human experts.
Fowke, Jay H; Koyama, Tatsuki; Fadare, Oluwole; Clark, Peter E
2016-01-01
BPH is a common disease associated with age and obesity. However, the biological pathways between obesity and BPH are unknown. Our objective was to investigate biomarkers of systemic and prostate tissue inflammation as potential mediators of the obesity and BPH association. Participants included 191 men without prostate cancer at prostate biopsy. Trained staff measured weight, height, waist and hip circumferences, and body composition by bioelectric impedance analysis. Systemic inflammation was estimated by serum IL-6, IL-1β, IL-8, and TNF-α; and by urinary prostaglandin E2 metabolite (PGE-M), F2-isoprostane (F2iP), and F2-isoprostane metabolite (F2iP-M) levels. Prostate tissue was scored for grade, aggressiveness, extent, and location of inflammatory regions, and also stained for CD3 and CD20 positive lymphocytes. Analyses investigated the association between multiple body composition scales, systemic inflammation, and prostate tissue inflammation against BPH outcomes, including prostate size at ultrasound and LUTS severity by the AUA-symptom index (AUA-SI). Prostate size was significantly associated with all obesity measures. For example, prostate volume was 5.5 to 9.0 mls larger comparing men in the 25th vs. 75th percentile of % body fat, fat mass (kg) or lean mass (kg). However, prostate size was not associated with proinflammatory cytokines, PGE-M, F2iP, F2iP-M, prostate tissue inflammation scores or immune cell infiltration. In contrast, the severity of prostate tissue inflammation was significantly associated with LUTS, such that there was a 7 point difference in AUA-SI between men with mild vs. severe inflammation (p = 0.004). Additionally, men with a greater waist-hip ratio (WHR) were significantly more likely to have severe prostate tissue inflammation (p = 0.02), and a high WHR was significantly associated with moderate/severe LUTS (OR = 2.56, p = 0.03) among those participants with prostate tissue inflammation. The WHR, an estimate of centralized obesity, was associated with the severity of inflammatory regions in prostate tissue and with LUTS severity among men with inflammation. Our results suggest centralized obesity advances prostate tissue inflammation to increase LUTS severity. Clinically targeting centralized fat deposition may reduce LUTS severity. Mechanistically, the lack of a clear relationship between systemic inflammatory or oxidative stress markers in blood or urine with prostate size or LUTS suggests pathways other than systemic inflammatory signaling may link body adiposity to BPH outcomes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chi, Y; Rezaeian, N Hassan; Hannan, R
Purpose: Intra-fractional prostate motion leads uncertainty on delivered dose in radiotherapy and may cause significant dose deviation from the planned dose distribution. This is especially a concern in scenarios with a high dose per fraction and hence a long delivery time, e.g. stereotactic body radiotherapy. Knowledge about intra-fractional prostate motion is valuable to address this problem, e.g. by reconstructing delivered dose and performing adaptation. This study proposes a new approach to determine intra-fractional prostate motion in VMAT via 2D/3D maker registration. Methods: At our institution, each patient has three markers implanted in the prostate. During treatment delivery, kV triggered imagesmore » were taken every three seconds to acquire 2D projection of 3D anatomy at the direction orthogonal to the therapeutic beam. Projected marker locations were identified on each projection image using template matching with geometric constraints. 3D prostate translation and rotation for each triggered image were obtained by solving an optimization problem, such that the calculated marker locations match the measured ones. Inter-image motion smoothness was employed as a constraint. We tested this method in simulation studies with five realistic prostate motion trajectories acquired via Calypso and in real phantom experiments. Results: For the simulation case, the motion range for these patients was 0.5∼6.0 mm. Root mean square (RMS) error of calculated motion along left-right (LR), anterior-posterior (AP) and cranial-caudal (CC) directions were 0.26mm, 0.36mm, and 0.016mm, respectively. The motion range in the phantom study along LR, AP, and CC directions were 15mm, 20mm and 10mm. The mean RMS errors along these directions were 1.99mm, 1.37mm and 0.22mm. Conclusion: A new prostate motion tracking algorithm based on kV triggered images has been developed and validated. Clinically acceptable accuracy has been achieved.« less
Shanechi, Maryam M.; Williams, Ziv M.; Wornell, Gregory W.; Hu, Rollin C.; Powers, Marissa; Brown, Emery N.
2013-01-01
Real-time brain-machine interfaces (BMI) have focused on either estimating the continuous movement trajectory or target intent. However, natural movement often incorporates both. Additionally, BMIs can be modeled as a feedback control system in which the subject modulates the neural activity to move the prosthetic device towards a desired target while receiving real-time sensory feedback of the state of the movement. We develop a novel real-time BMI using an optimal feedback control design that jointly estimates the movement target and trajectory of monkeys in two stages. First, the target is decoded from neural spiking activity before movement initiation. Second, the trajectory is decoded by combining the decoded target with the peri-movement spiking activity using an optimal feedback control design. This design exploits a recursive Bayesian decoder that uses an optimal feedback control model of the sensorimotor system to take into account the intended target location and the sensory feedback in its trajectory estimation from spiking activity. The real-time BMI processes the spiking activity directly using point process modeling. We implement the BMI in experiments consisting of an instructed-delay center-out task in which monkeys are presented with a target location on the screen during a delay period and then have to move a cursor to it without touching the incorrect targets. We show that the two-stage BMI performs more accurately than either stage alone. Correct target prediction can compensate for inaccurate trajectory estimation and vice versa. The optimal feedback control design also results in trajectories that are smoother and have lower estimation error. The two-stage decoder also performs better than linear regression approaches in offline cross-validation analyses. Our results demonstrate the advantage of a BMI design that jointly estimates the target and trajectory of movement and more closely mimics the sensorimotor control system. PMID:23593130
Johannsen, M; Gneveckow, U; Eckelt, L; Feussner, A; Waldöfner, N; Scholz, R; Deger, S; Wust, P; Loening, S A; Jordan, A
2005-11-01
The aim of this pilot study was to evaluate whether the technique of magnetic fluid hyperthermia can be used for minimally invasive treatment of prostate cancer. This paper presents the first clinical application of interstitial hyperthermia using magnetic nanoparticles in locally recurrent prostate cancer. Treatment planning was carried out using computerized tomography (CT) of the prostate. Based on the individual anatomy of the prostate and the estimated specific absorption rate (SAR) of magnetic fluids in prostatic tissue, the number and position of magnetic fluid depots required for sufficient heat deposition was calculated while rectum and urethra were spared. Nanoparticle suspensions were injected transperineally into the prostate under transrectal ultrasound and flouroscopy guidance. Treatments were delivered in the first magnetic field applicator for use in humans, using an alternating current magnetic field with a frequency of 100 kHz and variable field strength (0-18 kA m(-1)). Invasive thermometry of the prostate was carried out in the first and last of six weekly hyperthermia sessions of 60 min duration. CT-scans of the prostate were repeated following the first and last hyperthermia treatment to document magnetic nanoparticle distribution and the position of the thermometry probes in the prostate. Nanoparticles were retained in the prostate during the treatment interval of 6 weeks. Using appropriate software (AMIRA), a non-invasive estimation of temperature values in the prostate, based on intra-tumoural distribution of magnetic nanoparticles, can be performed and correlated with invasively measured intra-prostatic temperatures. Using a specially designed cooling device, treatment was well tolerated without anaesthesia. In the first patient treated, maximum and minimum intra-prostatic temperatures measured at a field strength of 4.0-5.0 kA m(-1) were 48.5 degrees C and 40.0 degrees C during the 1st treatment and 42.5 degrees C and 39.4 degrees C during the 6th treatment, respectively. These first clinical experiences prompted us to initiate a phase I study to evaluate feasibility, toxicity and quality of life during hyperthermia using magnetic nanoparticles in patients with biopsy-proven local recurrence of prostate cancer following radiotherapy with curative intent. To the authors' knowledge, this is the first report on clinical application of interstitial hyperthermia using magnetic nanoparticles in the treatment of human cancer.
Hyper-X Post-Flight Trajectory Reconstruction
NASA Technical Reports Server (NTRS)
Karlgaard, Christopher D.; Tartabini, Paul V.; Blanchard, RobertC.; Kirsch, Michael; Toniolo, Matthew D.
2004-01-01
This paper discusses the formulation and development of a trajectory reconstruction tool for the NASA X{43A/Hyper{X high speed research vehicle, and its implementation for the reconstruction and analysis of ight test data. Extended Kalman ltering techniques are employed to reconstruct the trajectory of the vehicle, based upon numerical integration of inertial measurement data along with redundant measurements of the vehicle state. The equations of motion are formulated in order to include the effects of several systematic error sources, whose values may also be estimated by the ltering routines. Additionally, smoothing algorithms have been implemented in which the nal value of the state (or an augmented state that includes other systematic error parameters to be estimated) and covariance are propagated back to the initial time to generate the best-estimated trajectory, based upon all available data. The methods are applied to the problem of reconstructing the trajectory of the Hyper-X vehicle from ight data.
Dawes, Richard; Passalacqua, Alessio; Wagner, Albert F; Sewell, Thomas D; Minkoff, Michael; Thompson, Donald L
2009-04-14
We develop two approaches for growing a fitted potential energy surface (PES) by the interpolating moving least-squares (IMLS) technique using classical trajectories. We illustrate both approaches by calculating nitrous acid (HONO) cis-->trans isomerization trajectories under the control of ab initio forces from low-level HF/cc-pVDZ electronic structure calculations. In this illustrative example, as few as 300 ab initio energy/gradient calculations are required to converge the isomerization rate constant at a fixed energy to approximately 10%. Neither approach requires any preliminary electronic structure calculations or initial approximate representation of the PES (beyond information required for trajectory initial conditions). Hessians are not required. Both approaches rely on the fitting error estimation properties of IMLS fits. The first approach, called IMLS-accelerated direct dynamics, propagates individual trajectories directly with no preliminary exploratory trajectories. The PES is grown "on the fly" with the computation of new ab initio data only when a fitting error estimate exceeds a prescribed tight tolerance. The second approach, called dynamics-driven IMLS fitting, uses relatively inexpensive exploratory trajectories to both determine and fit the dynamically accessible configuration space. Once exploratory trajectories no longer find configurations with fitting error estimates higher than the designated accuracy, the IMLS fit is considered to be complete and usable in classical trajectory calculations or other applications.
Is prostate cancer different in black men? Answers from 3 natural history models.
Tsodikov, Alex; Gulati, Roman; de Carvalho, Tiago M; Heijnsdijk, Eveline A M; Hunter-Merrill, Rachel A; Mariotto, Angela B; de Koning, Harry J; Etzioni, Ruth
2017-06-15
Black men in the United States have substantially higher prostate cancer incidence rates than the general population. The extent to which this incidence disparity is because prostate cancer is more prevalent, more aggressive, and/or more frequently diagnosed in black men is unknown. The authors estimated 3 independently developed models of prostate cancer natural history in black men and in the general population using an updated reconstruction of prostate-specific antigen screening, based on the National Health Interview Survey in 2005 and on prostate cancer incidence data from the Surveillance, Epidemiology, and End Results program during 1975 through 2000. By using the estimated models, the natural history of prostate cancer was compared between black men and the general population. The models projected that from 30% to 43% (range across models) of black men develop preclinical prostate cancer by age 85 years, a risk that is (relatively) 28% to 56% higher than that in the general population. Among men who had preclinical disease onset, black men had a similar risk of diagnosis (range, 35%-49%) compared with the general population (32%-44%), but their risk of progression to metastatic disease by the time of diagnosis was from 44% to 75% higher than that in the general population. Prostate cancer incidence patterns implicate higher incidence of preclinical disease and higher risk of metastatic progression among black men. The findings suggest screening black men earlier than white men and support further research into the benefit-harm tradeoffs of more aggressive screening policies for black men. Cancer 2017;123:2312-2319. © 2017 American Cancer Society. © 2017 American Cancer Society.
Replication of prostate cancer risk loci in a Japanese case-control association study.
Yamada, Hiroki; Penney, Kathryn L; Takahashi, Hiroyuki; Katoh, Takahiko; Yamano, Yuko; Yamakado, Minoru; Kimura, Takahiro; Kuruma, Hidetoshi; Kamata, Yuko; Egawa, Shin; Freedman, Matthew L
2009-10-07
Two prostate cancer genome-wide scans in populations of European ancestry identified several genetic variants that are strongly associated with prostate cancer risk. The effect of these risk variants and their cumulative effect in other populations are unknown. We evaluated the association of 23 risk single-nucleotide polymorphisms (SNPs) with prostate cancer risk and clinical covariates (Gleason score, tumor aggressiveness, and age at diagnosis) in men of Japanese ancestry (311 case subjects and 1035 control subjects) using unconditional logistic regression. We also used logistic regression to test the association between increasing numbers of independently associated risk alleles and the risk of prostate cancer, prostate cancer aggressiveness, and age at diagnosis. All statistical tests were two-sided. Seven of the 23 SNPs (five independent loci) were associated with prostate cancer risk (P values ranged from .0084 to 2.3 x 10(-8) and effect sizes [estimated as odds ratios, ORs] ranged from 1.35 to 1.82). None of the seven SNPs was associated with Gleason score or aggressive disease. rs6983561 and rs4430796 were associated with age at diagnosis (Ps = .0188 and .0339, respectively). Men with six or more risk alleles (27% of case patients and 11% of control subjects) had a higher risk of prostate cancer than men with two or fewer risk alleles (7% of case patients and 20% of control subjects) (OR = 6.22, P = 1.5 x 10(-12)). These results highlight the critical importance of considering ancestry in understanding how risk alleles influence disease and suggest that risk estimates and variants differ across populations. It is important to perform studies in multiple ancestral populations so that the composite genetic architecture of prostate cancer can be rigorously addressed.
Clinical Utility of Five Genetic Variants for Predicting Prostate Cancer Risk and Mortality
Salinas, Claudia A.; Koopmeiners, Joseph S.; Kwon, Erika M.; FitzGerald, Liesel; Lin, Daniel W.; Ostrander, Elaine A.; Feng, Ziding; Stanford, Janet L.
2009-01-01
Background A recent report suggests that the combination of five single-nucleotide polymorphisms (SNPs) at 8q24, 17q12, 17q24.3 and a family history of the disease may predict risk of prostate cancer. The present study tests the performance of these factors in prediction models for prostate cancer risk and prostate cancer-specific mortality. Methods SNPs were genotyped in population-based samples from Caucasians in King County, Washington. Incident cases (n=1308), aged 35–74, were compared to age-matched controls (n=1266) using logistic regression to estimate odds ratios (OR) associated with genotypes and family history. Cox proportional hazards models estimated hazard ratios for prostate cancer-specific mortality according to genotypes. Results The combination of SNP genotypes and family history was significantly associated with prostate cancer risk (ptrend=1.5 × 10−20). Men with ≥ five risk factors had an OR of 4.9 (95% CI 1.6 to 18.5) compared to men with none. However, this combination of factors did not improve the ROC curve after accounting for known risk predictors (i.e., age, serum PSA, family history). Neither the individual nor combined risk factors was associated with prostate cancer-specific mortality. Conclusion Genotypes for five SNPs plus family history are associated with a significant elevation in risk for prostate cancer and may explain up to 45% of prostate cancer in our population. However, they do not improve prediction models for assessing who is at risk of getting or dying from the disease, once known risk or prognostic factors are taken into account. Thus, this SNP panel may have limited clinical utility. PMID:19058137
Halpern, Joshua A; Shoag, Jonathan E; Artis, Amanda S; Ballman, Karla V; Sedrakyan, Art; Hershman, Dawn L; Wright, Jason D; Shih, Ya Chen Tina; Hu, Jim C
2017-02-01
Studies demonstrate that use of prostate-specific antigen screening decreased significantly following the US Preventive Services Task Force (USPSTF) recommendation against prostate-specific antigen screening in 2012. To determine downstream effects on practice patterns in prostate cancer diagnosis and treatment following the 2012 USPSTF recommendation. Procedural volumes of certifying and recertifying urologists from 2009 through 2016 were evaluated for variation in prostate biopsy and radical prostatectomy (RP) volume. Trends were confirmed using the New York Statewide Planning and Research Cooperative System and Nationwide Inpatient Sample. The study included a representative sample of urologists across practice settings and nationally representative sample of all RP discharges. We obtained operative case logs from the American Board of Urology and identified urologists performing at least 1 prostate biopsy (n = 5173) or RP (n = 3748), respectively. The 2012 USPSTF recommendation against routine population-wide prostate-specific antigen screening. Change in median biopsy and RP volume per urologist and national procedural volume. Following the USPSTF recommendation, median biopsy volume per urologist decreased from 29 to 21 (interquartile range [IQR}, 12-34; P < .001). After adjusting for physician and practice characteristics, biopsy volume decreased by 28.7% following 2012 (parameter estimate, -0.25; SE, 0.03; P < .001). Similarly, following the USPSTF recommendation, median RP volume per urologist decreased from 7 (IQR, 3-15) to 6 (IQR, 2-12) (P < .001), and in adjusted analyses, RP volume decreased 16.2% (parameter estimate, -0.15; SE, 0.05; P = .003). Following the 2012 USPSTF recommendation, prostate biopsy and RP volumes decreased significantly. A panoramic vantage point is needed to evaluate the long-term consequences of the 2012 USPSTF recommendation.
A model describing diffusion in prostate cancer.
Gilani, Nima; Malcolm, Paul; Johnson, Glyn
2017-07-01
Quantitative diffusion MRI has frequently been studied as a means of grading prostate cancer. Interpretation of results is complicated by the nature of prostate tissue, which consists of four distinct compartments: vascular, ductal lumen, epithelium, and stroma. Current diffusion measurements are an ill-defined weighted average of these compartments. In this study, prostate diffusion is analyzed in terms of a model that takes explicit account of tissue compartmentalization, exchange effects, and the non-Gaussian behavior of tissue diffusion. The model assumes that exchange between the cellular (ie, stromal plus epithelial) and the vascular and ductal compartments is slow. Ductal and cellular diffusion characteristics are estimated by Monte Carlo simulation and a two-compartment exchange model, respectively. Vascular pseudodiffusion is represented by an additional signal at b = 0. Most model parameters are obtained either from published data or by comparing model predictions with the published results from 41 studies. Model prediction error is estimated using 10-fold cross-validation. Agreement between model predictions and published results is good. The model satisfactorily explains the variability of ADC estimates found in the literature. A reliable model that predicts the diffusion behavior of benign and cancerous prostate tissue of different Gleason scores has been developed. Magn Reson Med 78:316-326, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Najafi, M; Han, B; Hancock, S
Purpose: Prostate SABR is emerging as a clinically viable, potentially cost effective alternative to prostate IMRT but its adoption is contingent on providing solutions for accurate tracking during beam delivery. Our goal is to evaluate the performance of the Clarity Autoscan ultrasound monitoring system for inter-fractional prostate motion tracking in both phantoms and in-vivo. Methods: In-vivo evaluation was performed under IRB protocol to allow data collection in prostate patients treated with VMAT whereby prostate was imaged through the acoustic window of the perineum. The probe was placed before KV imaging and real-time tracking was started and continued until the endmore » of treatment. Initial absolute 3D positions of fiducials were estimated from KV images. Fiducial positions in MV images subsequently acquired during beam delivery were compared with predicted positions based on Clarity estimated motion. Results: Phantom studies with motion amplitudes of ±1.5, ±3, ±6 mm in lateral direction and ±2 mm in longitudinal direction resulted in tracking errors of −0.03 ± 0.3, −0.04 ± 0.6, −0.2 ± 0.9 mm, respectively, in lateral direction and −0.05 ± 0.30 mm in longitudinal direction. In phantom, measured and predicted fiducial positions in MV images were within 0.1 ± 0.6 mm. Four patients consented to participate in the study and data was acquired over a total of 140 fractions. MV imaging tracking was possible in about 75% of the time (due to occlusion of fiducials) compared to 100% with Clarity. Overall range of estimated motion by Clarity was 0 to 4.0 mm. In-vivo fiducial localization error was 1.2 ± 1.0 mm compared to 1.8 ± 1.9 mm if not taking Clarity estimated motion into account. Conclusion: Real-time transperineal ultrasound tracking reduces uncertainty in prostate position due to intrafractional motion. Research was supported by Elekta.« less
Fractionated changes in prostate cancer radiotherapy using cone-beam computed tomography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Tzung-Chi, E-mail: tzungchi.huang@mail.cmu.edu.tw; Department of Biomedical Informatics, Asia University, Taichung City, Taiwan; Chou, Kuei-Ting
2015-10-01
The high mobility of the bladder and the rectum causes uncertainty in radiation doses prescribed to patients with prostate cancer who undergo radiotherapy (RT) multifraction treatments. The purpose of this study was to estimate the dose received by the bladder, rectum, and prostate from multifraction treatments using daily cone-beam computed tomography (CBCT). Overall, 28 patients with prostate cancer who planned to receive radiation treatments were enrolled in the study. The acquired CBCT before the treatment delivery was registered with the planning CT to map the dose distribution used in the treatment plan for estimating the received dose during clinical treatment.more » For all 28 patients with 112 data sets, the mean percentage differences (± standard deviation) in the volume and radiation dose were 44% (± 41) and 18% (± 17) for the bladder, 20% (± 21) and 2% (± 2) for the prostate, and 36% (± 29) and 22% (± 15) for the rectum, respectively. Substantial differences between the volumes and radiation dose and those specified in treatment plans were observed. Besides the use of image-guided RT to improve patient setup accuracy, further consideration of large changes in bladder and rectum volumes is strongly suggested when using external beam radiation for prostate cancer.« less
2013-10-01
collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources...gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate...variants which explain much more than a small amount of risk for prostate cancer among a small population of men. Even less progress has been made
Prostate Cancer Risk Prediction Models
Developing statistical models that estimate the probability of developing prostate cancer over a defined period of time will help clinicians identify individuals at higher risk of specific cancers, allowing for earlier or more frequent screening and counseling of behavioral changes to decrease risk.
A supervoxel-based segmentation method for prostate MR images
NASA Astrophysics Data System (ADS)
Tian, Zhiqiang; Liu, LiZhi; Fei, Baowei
2015-03-01
Accurate segmentation of the prostate has many applications in prostate cancer diagnosis and therapy. In this paper, we propose a "Supervoxel" based method for prostate segmentation. The prostate segmentation problem is considered as assigning a label to each supervoxel. An energy function with data and smoothness terms is used to model the labeling process. The data term estimates the likelihood of a supervoxel belongs to the prostate according to a shape feature. The geometric relationship between two neighboring supervoxels is used to construct a smoothness term. A threedimensional (3D) graph cut method is used to minimize the energy function in order to segment the prostate. A 3D level set is then used to get a smooth surface based on the output of the graph cut. The performance of the proposed segmentation algorithm was evaluated with respect to the manual segmentation ground truth. The experimental results on 12 prostate volumes showed that the proposed algorithm yields a mean Dice similarity coefficient of 86.9%+/-3.2%. The segmentation method can be used not only for the prostate but also for other organs.
Hurtado, Felipe K.; Weber, Benjamin; Derendorf, Hartmut; Hochhaus, Guenther
2014-01-01
Levofloxacin is a broad-spectrum fluoroquinolone used in the treatment of both acute and chronic bacterial prostatitis. Currently, the treatment of bacterial prostatitis is still difficult, especially due to the poor distribution of many antimicrobials into the prostate, thus preventing the drug to reach effective interstitial concentrations at the infection site. Newer fluoroquinolones show a greater penetration into the prostate. In the present study, we compared the unbound levofloxacin prostate concentrations measured by microdialysis to those in plasma after a 7-mg/kg intravenous bolus dose to Wistar rats. Plasma and dialysate samples were analyzed using a validated high-pressure liquid chromatography-fluorescence method. Both noncompartmental analysis (NCA) and population-based compartmental modeling (NONMEM 6) were performed. Unbound prostate tissue concentrations represented 78% of unbound plasma levels over a period of 12 h by comparing the extent of exposure (unbound AUC0–∞) of 6.4 and 4.8 h·μg/ml in plasma and tissue, respectively. A three-compartment model with simultaneous passive diffusion and saturable distribution kinetics from the prostate to the central compartment gave the best results in terms of curve fitting, precision of parameter estimates, and model stability. The following parameter values were estimated by the population model: V1 (0.38 liter; where V1 represents the volume of the central compartment), CL (0.22 liter/h), k12 (2.27 h−1), k21 (1.44 h−1), k13 (0.69 h−1), Vmax (7.19 μg/h), kM (0.35 μg/ml), V3/fuprostate (0.05 liter; where fuprostate represents the fraction unbound in the prostate), and k31 (3.67 h−1). The interindividual variability values for V1, CL, Vmax, and kM were 21, 37, 42, and 76%, respectively. Our results suggest that levofloxacin is likely to be substrate for efflux transporters in the prostate. PMID:24217697
Prevalence of BPH and lower urinary tract symptoms in West Africans.
Chokkalingam, A P; Yeboah, E D; Demarzo, A; Netto, G; Yu, K; Biritwum, R B; Tettey, Y; Adjei, A; Jadallah, S; Li, Y; Chu, L W; Chia, D; Niwa, S; Partin, A; Thompson, I M; Roehrborn, C; Hoover, R N; Hsing, A W
2012-06-01
BPH and lower urinary tract symptoms (LUTS) are very common among older men in Western countries. However, the prevalence of these two conditions in the developing countries is less clear. We assessed the age-standardized prevalence of BPH and/or LUTS among West Africans in a probability sample of 950 men aged 50-74 in Accra, Ghana, with no evidence of biopsy-confirmed prostate cancer after screening with PSA and digital rectal examination (DRE). Information on LUTS was based on self-reports of the International Prostate Symptom Score (IPSS). BPH was estimated using DRE, PSA levels and imputed prostate volume. The prevalence of DRE-detected enlarged prostate was 62.3%, while that of PSA≥1.5 ng ml(-1) (an estimate of prostate volume ≥ 30 cm(3)) was 35.3%. The prevalence of moderate-to-severe LUTS (IPSS≥8) was 19.9%. The prevalence of IPSS≥8 and an enlarged prostate on DRE was 13.3%. Although there is no universally agreed-upon definition of BPH/LUTS, making comparisons across populations difficult, BPH and/or LUTS appear to be quite common among older Ghanaian men. We found that after age standardization, the prevalence of DRE-detected enlarged prostate in Ghanaian men is higher than previously reported for American men, but the prevalence of LUTS was lower than previously reported for African Americans. Further studies are needed to confirm these findings and identify the risk factors for BPH in both Africans and African Americans.
NASA Astrophysics Data System (ADS)
Casasent, David P.; Shenoy, Rajesh
1997-10-01
Classification and pose estimation of distorted input objects are considered. The feature space trajectory representation of distorted views of an object is used with a new eigenfeature space. For a distorted input object, the closest trajectory denotes the class of the input and the closest line segment on it denotes its pose. If an input point is too far from a trajectory, it is rejected as clutter. New methods for selecting Fukunaga-Koontz discriminant vectors, the number of dominant eigenvectors per class and for determining training, and test set compatibility are presented.
Sharpley, Christopher F; Christie, David R H; Bitsika, Vicki; Miller, Bradley J
2017-01-01
The aim of this study was to investigate the effects of hormone therapy (HT) on depression and depressive symptoms in prostate cancer patients undergoing 6 months of HT. One hundred two prostate cancer patients who had been prescribed HT completed the Zung Self-rating Depression Scale (SDS) and two questions about their sexual enjoyment and performance, plus a background questionnaire before HT, after 8 to 10 weeks of HT and again after 16 to 20 weeks of HT. There was a significant increase in SDS scores from before to during HT. High depression score before HT was a significant predictor of later increases in depression during HT. Increases in depressive symptoms were restricted to 8 of the 20 SDS symptoms, the most powerful change being in sexual anhedonia, which was a result of decreased ability to perform during sexual activity. The association between HT and elevated depression is confirmed, but the relative influence of sexual anhedonia over other depressive symptoms expands the understanding of this association. The effects of decreased ability to perform during sex appear to dominate the increase in depression during HT. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Roobol, Monique J; Kerkhof, Melissa; Schröder, Fritz H; Cuzick, Jack; Sasieni, Peter; Hakama, Matti; Stenman, Ulf Hakan; Ciatto, Stefano; Nelen, Vera; Kwiatkowski, Maciej; Lujan, Marcos; Lilja, Hans; Zappa, Marco; Denis, Louis; Recker, Franz; Berenguer, Antonio; Ruutu, Mirja; Kujala, Paula; Bangma, Chris H; Aus, Gunnar; Tammela, Teuvo L J; Villers, Arnauld; Rebillard, Xavier; Moss, Sue M; de Koning, Harry J; Hugosson, Jonas; Auvinen, Anssi
2009-10-01
Prostate-specific antigen (PSA) based screening for prostate cancer (PCa) has been shown to reduce prostate specific mortality by 20% in an intention to screen (ITS) analysis in a randomised trial (European Randomised Study of Screening for Prostate Cancer [ERSPC]). This effect may be diluted by nonattendance in men randomised to the screening arm and contamination in men randomised to the control arm. To assess the magnitude of the PCa-specific mortality reduction after adjustment for nonattendance and contamination. We analysed the occurrence of PCa deaths during an average follow-up of 9 yr in 162,243 men 55-69 yr of age randomised in seven participating centres of the ERSPC. Centres were also grouped according to the type of randomisation (ie, before or after informed written consent). Nonattendance was defined as nonattending the initial screening round in ERSPC. The estimate of contamination was based on PSA use in controls in ERSPC Rotterdam. Relative risks (RRs) with 95% confidence intervals (CIs) were compared between an ITS analysis and analyses adjusting for nonattendance and contamination using a statistical method developed for this purpose. In the ITS analysis, the RR of PCa death in men allocated to the intervention arm relative to the control arm was 0.80 (95% CI, 0.68-0.96). Adjustment for nonattendance resulted in a RR of 0.73 (95% CI, 0.58-0.93), and additional adjustment for contamination using two different estimates led to estimated reductions of 0.69 (95% CI, 0.51-0.92) to 0.71 (95% CI, 0.55-0.93), respectively. Contamination data were obtained through extrapolation of single-centre data. No heterogeneity was found between the groups of centres. PSA screening reduces the risk of dying of PCa by up to 31% in men actually screened. This benefit should be weighed against a degree of overdiagnosis and overtreatment inherent in PCa screening.
Hanly, Paul; Timmons, Aileen; Walsh, Paul M; Sharp, Linda
2012-05-01
Productivity costs constitute a substantial proportion of the total societal costs associated with cancer. We compared the results of applying two different analytical methods--the traditional human capital approach (HCA) and the emerging friction cost approach (FCA)--to estimate breast and prostate cancer productivity costs in Ireland in 2008. Data from a survey of breast and prostate cancer patients were combined with population-level survival estimates and a national wage data set to calculate costs of temporary disability (cancer-related work absence), permanent disability (workforce departure, reduced working hours), and premature mortality. For breast cancer, productivity costs per person using the HCA were € 193,425 and those per person using the FCA were € 8,103; for prostate cancer, the comparable estimates were € 109,154 and € 8,205, respectively. The HCA generated higher costs for younger patients (breast cancer) because of greater lifetime earning potential. In contrast, the FCA resulted in higher productivity costs for older male patients (prostate cancer) commensurate with higher earning capacity over a shorter time period. Reduced working hours postcancer was a key driver of total HCA productivity costs. HCA costs were sensitive to assumptions about discount and growth rates. FCA costs were sensitive to assumptions about the friction period. The magnitude of the estimates obtained in this study illustrates the importance of including productivity costs when considering the economic impact of illness. Vastly different results emerge from the application of the HCA and the FCA, and this finding emphasizes the importance of choosing the study perspective carefully and being explicit about assumptions that underpin the methods. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Adjacent slice prostate cancer prediction to inform MALDI imaging biomarker analysis
NASA Astrophysics Data System (ADS)
Chuang, Shao-Hui; Sun, Xiaoyan; Cazares, Lisa; Nyalwidhe, Julius; Troyer, Dean; Semmes, O. John; Li, Jiang; McKenzie, Frederic D.
2010-03-01
Prostate cancer is the second most common type of cancer among men in US [1]. Traditionally, prostate cancer diagnosis is made by the analysis of prostate-specific antigen (PSA) levels and histopathological images of biopsy samples under microscopes. Proteomic biomarkers can improve upon these methods. MALDI molecular spectra imaging is used to visualize protein/peptide concentrations across biopsy samples to search for biomarker candidates. Unfortunately, traditional processing methods require histopathological examination on one slice of a biopsy sample while the adjacent slice is subjected to the tissue destroying desorption and ionization processes of MALDI. The highest confidence tumor regions gained from the histopathological analysis are then mapped to the MALDI spectra data to estimate the regions for biomarker identification from the MALDI imaging. This paper describes a process to provide a significantly better estimate of the cancer tumor to be mapped onto the MALDI imaging spectra coordinates using the high confidence region to predict the true area of the tumor on the adjacent MALDI imaged slice.
Orion Exploration Flight Test 1 (EFT-1) Best Estimated Trajectory Development
NASA Technical Reports Server (NTRS)
Holt, Greg N.; Brown, Aaron
2016-01-01
The Orion Exploration Flight Test 1 (EFT-1) mission successfully flew on Dec 5, 2014 atop a Delta IV Heavy launch vehicle. The goal of Orions maiden flight was to stress the system by placing an uncrewed vehicle on a high-energy trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. The Orion navigation team combined all trajectory data from the mission into a Best Estimated Trajectory (BET) product. There were significant challenges in data reconstruction and many lessons were learned for future missions. The team used an estimation filter incorporating radar tracking, onboard sensors (Global Positioning System and Inertial Measurement Unit), and day-of-flight weather balloons to evaluate the true trajectory flown by Orion. Data was published for the entire Orion EFT-1 flight, plus objects jettisoned during entry such as the Forward Bay Cover. The BET customers include approximately 20 disciplines within Orion who will use the information for evaluating vehicle performance and influencing future design decisions.
Hyper-X Mach 10 Trajectory Reconstruction
NASA Technical Reports Server (NTRS)
Karlgaard, Christopher D.; Martin, John G.; Tartabini, Paul V.; Thornblom, Mark N.
2005-01-01
This paper discusses the formulation and development of a trajectory reconstruction tool for the NASA X-43A/Hyper-X high speed research vehicle, and its implementation for the reconstruction and analysis of flight test data. Extended Kalman filtering techniques are employed to reconstruct the trajectory of the vehicle, based upon numerical integration of inertial measurement data along with redundant measurements of the vehicle state. The equations of motion are formulated in order to include the effects of several systematic error sources, whose values may also be estimated by the filtering routines. Additionally, smoothing algorithms have been implemented in which the final value of the state (or an augmented state that includes other systematic error parameters to be estimated) and covariance are propagated back to the initial time to generate the best-estimated trajectory, based upon all available data. The methods are applied to the problem of reconstructing the trajectory of the Hyper-X vehicle from data obtained during the Mach 10 test flight, which occurred on November 16th 2004.
Red wine consumption and risk of prostate cancer: the California men's health study.
Chao, Chun; Haque, Reina; Van Den Eeden, Stephen K; Caan, Bette J; Poon, Kwun-Yee T; Quinn, Virginia P
2010-01-01
Red wine contains polyphenol antioxidants that inhibit prostate cancer development in animal studies. We investigated the effect of red wine intake on the risk of prostate cancer using data prospectively collected in the California Men's Health Study (CMHS). CMHS is a multiethnic cohort of 84,170 men aged 45-69 years who were members of the Kaiser Permanente Southern and Northern California Health Plans. Information on demographic and lifestyle factors was collected using mailed questionnaires between 2002 and 2003. We used Cox models to estimate the effect of red wine on prostate cancer risk, adjusting for potential confounders. A total of 1,340 incident prostate cancer cases identified from Surveillance, Epidemiology and End Result-affiliated cancer registries were included in the analyses. We did not find a clear association between red wine intake and risk of prostate cancer. Hazard ratio (HR) estimates for consuming <1 drink/week, > or =1 drink/week but <1 drink/day and > or =1 drink/day were 0.89, 95% confidence interval (0.74-1.07), 0.99 (0.83-1.17) and 0.88 (0.70-1.12), respectively. Further, we observed no linear dose response. The lack of association for red wine intake was consistently observed when we restricted the analyses to those with and without a history of PSA screening. In addition, we also did not observe any association with prostate cancer for beer, white wine, liquor or combined alcoholic beverage intake (HR for combined alcoholic beverage intake of > or =5 drinks/day = 1.16 (0.83-1.63). Neither red wine nor total alcohol consumption were associated with prostate cancer risk in this population of moderate drinkers.
Anderson, Emma L; Tilling, Kate; Fraser, Abigail; Macdonald-Wallis, Corrie; Emmett, Pauline; Cribb, Victoria; Northstone, Kate; Lawlor, Debbie A; Howe, Laura D
2013-07-01
Methods for the assessment of changes in dietary intake across the life course are underdeveloped. We demonstrate the use of linear-spline multilevel models to summarize energy-intake trajectories through childhood and adolescence and their application as exposures, outcomes, or mediators. The Avon Longitudinal Study of Parents and Children assessed children's dietary intake several times between ages 3 and 13 years, using both food frequency questionnaires (FFQs) and 3-day food diaries. We estimated energy-intake trajectories for 12,032 children using linear-spline multilevel models. We then assessed the associations of these trajectories with maternal body mass index (BMI), and later offspring BMI, and also their role in mediating the relation between maternal and offspring BMIs. Models estimated average and individual energy intake at 3 years, and linear changes in energy intake from age 3 to 7 years and from age 7 to 13 years. By including the exposure (in this example, maternal BMI) in the multilevel model, we were able to estimate the average energy-intake trajectories across levels of the exposure. When energy-intake trajectories are the exposure for a later outcome (in this case offspring BMI) or a mediator (between maternal and offspring BMI), results were similar, whether using a two-step process (exporting individual-level intercepts and slopes from multilevel models and using these in linear regression/path analysis), or a single-step process (multivariate multilevel models). Trajectories were similar when FFQs and food diaries were assessed either separately, or when combined into one model. Linear-spline multilevel models provide useful summaries of trajectories of dietary intake that can be used as an exposure, outcome, or mediator.
Estimation of Center of Mass Trajectory using Wearable Sensors during Golf Swing.
Najafi, Bijan; Lee-Eng, Jacqueline; Wrobel, James S; Goebel, Ruben
2015-06-01
This study suggests a wearable sensor technology to estimate center of mass (CoM) trajectory during a golf swing. Groups of 3, 4, and 18 participants were recruited, respectively, for the purpose of three validation studies. Study 1 examined the accuracy of the system to estimate a 3D body segment angle compared to a camera-based motion analyzer (Vicon®). Study 2 assessed the accuracy of three simplified CoM trajectory models. Finally, Study 3 assessed the accuracy of the proposed CoM model during multiple golf swings. A relatively high agreement was observed between wearable sensors and the reference (Vicon®) for angle measurement (r > 0.99, random error <1.2° (1.5%) for anterior-posterior; <0.9° (2%) for medial-lateral; and <3.6° (2.5%) for internal-external direction). The two-link model yielded a better agreement with the reference system compared to one-link model (r > 0.93 v. r = 0.52, respectively). On the same note, the proposed two-link model estimated CoM trajectory during golf swing with relatively good accuracy (r > 0.9, A-P random error <1cm (7.7%) and <2cm (10.4%) for M-L). The proposed system appears to accurately quantify the kinematics of CoM trajectory as a surrogate of dynamic postural control during an athlete's movement and its portability, makes it feasible to fit the competitive environment without restricting surface type. Key pointsThis study demonstrates that wearable technology based on inertial sensors are accurate to estimate center of mass trajectory in complex athletic task (e.g., golf swing)This study suggests that two-link model of human body provides optimum tradeoff between accuracy and minimum number of sensor module for estimation of center of mass trajectory in particular during fast movements.Wearable technologies based on inertial sensors are viable option for assessing dynamic postural control in complex task outside of gait laboratory and constraints of cameras, surface, and base of support.
Sutcliffe, Siobhan; Grubb, Robert L.; Platz, Elizabeth A.; Ragard, Lawrence R.; Riley, Thomas L.; Kazin, Sally S.; Hayes, Richard B.; Hsing, Ann W.; Andriole, Gerald L.
2011-01-01
Objectives To investigate the relationship between non-steroidal anti-inflammatory drug (NSAID) use and the incidence of benign prostatic hyperplasia (BPH)-related outcomes and nocturia, a lower urinary tract symptom (LUTS) of BPH, in light of accumulating evidence suggesting a role for inflammation in BPH/LUTS development. Patients and methods At baseline, participants in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial completed questions on recent, regular aspirin and ibuprofen use, BPH surgery, diagnosis of an enlarged prostate/BPH, and nocturia. Participants in the intervention arm also underwent a digital rectal examination (DRE), from which prostate dimensions were estimated, as well as a prostate-specific antigen (PSA) test. Only participants in the intervention arm without BPH/LUTS at baseline were included in the analysis (n = 4771). During follow-up, participants underwent annual DREs and PSA tests, provided annual information on finasteride use, and completed a supplemental questionnaire in 2006–2008 that included additional questions on diagnosis of an enlarged prostate/BPH and nocturia. Information collected was used to investigate regular aspirin or ibuprofen use in relation to the incidence of six BPH/LUTS definitions: diagnosis of an enlarged prostate/BPH, nocturia (waking two or more times per night to urinate), finasteride use, any self-reported BPH/LUTS, prostate enlargement (estimated prostate volume ≥ 30 mL on any follow-up DRE) and elevation in PSA level (> 1.4 ng/mL on any follow-up PSA test). Results Generally, null results were observed for any recent, regular aspirin or ibuprofen use (risk ratio = 0.92–1.21, P = 0.043–0.91) and frequency of use (risk ratio for one category increase in NSAID use = 0.98–1.11, P-trends = 0.10–0.99) with incident BPH/LUTS. Conclusions The findings obtained in the present study do not support a protective role for recent NSAID use in BPH/LUTS development. PMID:22429766
De Luca, Stefano; Passera, Roberto; Bollito, Enrico; Manfredi, Matteo; Scarpa, Roberto Mario; Sottile, Antonino; Randone, Donato Franco; Porpiglia, Francesco
2014-12-01
To determine if prostate cancer gene 3 (PCA3) score, Prostate Health Index (PHI), and percent free prostate-specific antigen (%fPSA) may be used to differentiate prostatitis from prostate cancer (PCa), benign prostatic hyperplasia (BPH) and high-grade prostate intraepithelial neoplasia (HG-PIN) in patients with elevated PSA and negative digital rectal examination (DRE). in the present prospective study, 274 patients, undergoing PCA3 score, PHI and %fPSA assessments before initial biopsy, were enrolled. Three multivariate logistic regression models were used to test PCA3 score, PHI and %fPSA as risk factors for prostatitis vs. PCa, vs. BPH, and vs. HG-PIN. All the analyses were performed for the whole patient cohort and for the 'gray zone' of PSA (4-10 ng/ml) cohort (188 individuals). The determinants for prostatitis vs. PCa were PCA3 score, PHI and %fPSA (Odds Ratio [OR]=0.97, 0.96 and 0.94, respectively). Unit increase of PHI was the only risk factor for prostatitis vs. BPH (OR=1.06), and unit increase of PCA3 score for HG-PIN vs. prostatitis (OR=0.98). In the 'gray zone' PSA cohort, the determinants for prostatitis vs. PCa were PCA3 score, PHI and %fPSA (OR=0.96, 0.94 and 0.92, respectively), PCA3 score and PHI for prostatitis vs. BPH (OR=0.96 and 1.08, respectively), and PCA3 score for prostatitis vs. HG-PIN (OR=0.97). The clinical benefit of using PCA3 score and PHI to estimate prostatitis vs. PCa was comparable; even %fPSA had good diagnostic performance, being a faster and cheaper marker. PHI was the only determinant for prostatitis vs. BPH, while PCA3 score for prostatitis vs. HG-PIN. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
Lo, Kam W
2017-06-01
The trajectory of a supersonic bullet, which is subjected to drag and gravity, is curvilinear and the supersonic flight of the bullet generates a ballistic shock wave (SW). A model for the differential time of arrival (DTOA) of the SW at a pair of acoustic sensors is derived for a given bullet trajectory, which is fully described by seven parameters including the drag coefficient exponent and ballistic constant of the bullet. Assuming that the drag coefficient exponent is 0.5, the DTOA model is used to develop a nonlinear least-squares (NLS) method to estimate the other six trajectory parameters using DTOA of SW measurements from each node (which comprises a small acoustic sensor array) of an asynchronous sensor network. The position of the shooter and the muzzle speed of the bullet are then determined by tracing the estimated bullet trajectory back to topographic or man-made obstructions on a digital map. The effectiveness of the NLS method is verified using simulated data for different types of real bullets, and the error standard deviations in the parameter estimates are close to the Cramer-Rao lower bounds.
NASA Astrophysics Data System (ADS)
Latypov, A. F.
2009-03-01
The fuel economy was estimated at boost trajectory of aerospace plane during energy supply to the free stream. Initial and final velocities of the flight were given. A model of planning flight above cold air in infinite isobaric thermal wake was used. The comparison of fuel consumption was done at optimal trajectories. The calculations were done using a combined power plant consisting of ramjet and liquid-propellant engine. An exergy model was constructed in the first part of the paper for estimating the ramjet thrust and specific impulse. To estimate the aerodynamic drag of aircraft a quadratic dependence on aerodynamic lift is used. The energy for flow heating is obtained at the sacrifice of an equivalent decrease of exergy of combustion products. The dependencies are obtained for increasing the range coefficient of cruise flight at different Mach numbers. In the second part of the paper, a mathematical model is presented for the boost part of the flight trajectory of the flying vehicle and computational results for reducing the fuel expenses at the boost trajectory at a given value of the energy supplied in front of the aircraft.
Hu, Xinyao; Zhao, Jun; Peng, Dongsheng; Sun, Zhenglong; Qu, Xingda
2018-02-01
Postural control is a complex skill based on the interaction of dynamic sensorimotor processes, and can be challenging for people with deficits in sensory functions. The foot plantar center of pressure (COP) has often been used for quantitative assessment of postural control. Previously, the foot plantar COP was mainly measured by force plates or complicated and expensive insole-based measurement systems. Although some low-cost instrumented insoles have been developed, their ability to accurately estimate the foot plantar COP trajectory was not robust. In this study, a novel individual-specific nonlinear model was proposed to estimate the foot plantar COP trajectories with an instrumented insole based on low-cost force sensitive resistors (FSRs). The model coefficients were determined by a least square error approximation algorithm. Model validation was carried out by comparing the estimated COP data with the reference data in a variety of postural control assessment tasks. We also compared our data with the COP trajectories estimated by the previously well accepted weighted mean approach. Comparing with the reference measurements, the average root mean square errors of the COP trajectories of both feet were 2.23 mm (±0.64) (left foot) and 2.72 mm (±0.83) (right foot) along the medial-lateral direction, and 9.17 mm (±1.98) (left foot) and 11.19 mm (±2.98) (right foot) along the anterior-posterior direction. The results are superior to those reported in previous relevant studies, and demonstrate that our proposed approach can be used for accurate foot plantar COP trajectory estimation. This study could provide an inexpensive solution to fall risk assessment in home settings or community healthcare center for the elderly. It has the potential to help prevent future falls in the elderly.
Hu, Xinyao; Zhao, Jun; Peng, Dongsheng
2018-01-01
Postural control is a complex skill based on the interaction of dynamic sensorimotor processes, and can be challenging for people with deficits in sensory functions. The foot plantar center of pressure (COP) has often been used for quantitative assessment of postural control. Previously, the foot plantar COP was mainly measured by force plates or complicated and expensive insole-based measurement systems. Although some low-cost instrumented insoles have been developed, their ability to accurately estimate the foot plantar COP trajectory was not robust. In this study, a novel individual-specific nonlinear model was proposed to estimate the foot plantar COP trajectories with an instrumented insole based on low-cost force sensitive resistors (FSRs). The model coefficients were determined by a least square error approximation algorithm. Model validation was carried out by comparing the estimated COP data with the reference data in a variety of postural control assessment tasks. We also compared our data with the COP trajectories estimated by the previously well accepted weighted mean approach. Comparing with the reference measurements, the average root mean square errors of the COP trajectories of both feet were 2.23 mm (±0.64) (left foot) and 2.72 mm (±0.83) (right foot) along the medial–lateral direction, and 9.17 mm (±1.98) (left foot) and 11.19 mm (±2.98) (right foot) along the anterior–posterior direction. The results are superior to those reported in previous relevant studies, and demonstrate that our proposed approach can be used for accurate foot plantar COP trajectory estimation. This study could provide an inexpensive solution to fall risk assessment in home settings or community healthcare center for the elderly. It has the potential to help prevent future falls in the elderly. PMID:29389857
Jiang, Wenwen; Larson, Peder E Z; Lustig, Michael
2018-03-09
To correct gradient timing delays in non-Cartesian MRI while simultaneously recovering corruption-free auto-calibration data for parallel imaging, without additional calibration scans. The calibration matrix constructed from multi-channel k-space data should be inherently low-rank. This property is used to construct reconstruction kernels or sensitivity maps. Delays between the gradient hardware across different axes and RF receive chain, which are relatively benign in Cartesian MRI (excluding EPI), lead to trajectory deviations and hence data inconsistencies for non-Cartesian trajectories. These in turn lead to higher rank and corrupted calibration information which hampers the reconstruction. Here, a method named Simultaneous Auto-calibration and Gradient delays Estimation (SAGE) is proposed that estimates the actual k-space trajectory while simultaneously recovering the uncorrupted auto-calibration data. This is done by estimating the gradient delays that result in the lowest rank of the calibration matrix. The Gauss-Newton method is used to solve the non-linear problem. The method is validated in simulations using center-out radial, projection reconstruction and spiral trajectories. Feasibility is demonstrated on phantom and in vivo scans with center-out radial and projection reconstruction trajectories. SAGE is able to estimate gradient timing delays with high accuracy at a signal to noise ratio level as low as 5. The method is able to effectively remove artifacts resulting from gradient timing delays and restore image quality in center-out radial, projection reconstruction, and spiral trajectories. The low-rank based method introduced simultaneously estimates gradient timing delays and provides accurate auto-calibration data for improved image quality, without any additional calibration scans. © 2018 International Society for Magnetic Resonance in Medicine.
NASA Technical Reports Server (NTRS)
Haering, E. A., Jr.; Burcham, F. W., Jr.
1984-01-01
A simulation study was conducted to optimize minimum time and fuel consumption paths for an F-15 airplane powered by two F100 Engine Model Derivative (EMD) engines. The benefits of using variable stall margin (uptrim) to increase performance were also determined. This study supports the NASA Highly Integrated Digital Electronic Control (HIDEC) program. The basis for this comparison was minimum time and fuel used to reach Mach 2 at 13,716 m (45,000 ft) from the initial conditions of Mach 0.15 at 1524 m (5000 ft). Results were also compared to a pilot's estimated minimum time and fuel trajectory determined from the F-15 flight manual and previous experience. The minimum time trajectory took 15 percent less time than the pilot's estimate for the standard EMD engines, while the minimum fuel trajectory used 1 percent less fuel than the pilot's estimate for the minimum fuel trajectory. The F-15 airplane with EMD engines and uptrim, was 23 percent faster than the pilot's estimate. The minimum fuel used was 5 percent less than the estimate.
NASA Astrophysics Data System (ADS)
Sikora, Grzegorz; Teuerle, Marek; Wyłomańska, Agnieszka; Grebenkov, Denis
2017-08-01
The most common way of estimating the anomalous scaling exponent from single-particle trajectories consists of a linear fit of the dependence of the time-averaged mean-square displacement on the lag time at the log-log scale. We investigate the statistical properties of this estimator in the case of fractional Brownian motion (FBM). We determine the mean value, the variance, and the distribution of the estimator. Our theoretical results are confirmed by Monte Carlo simulations. In the limit of long trajectories, the estimator is shown to be asymptotically unbiased, consistent, and with vanishing variance. These properties ensure an accurate estimation of the scaling exponent even from a single (long enough) trajectory. As a consequence, we prove that the usual way to estimate the diffusion exponent of FBM is correct from the statistical point of view. Moreover, the knowledge of the estimator distribution is the first step toward new statistical tests of FBM and toward a more reliable interpretation of the experimental histograms of scaling exponents in microbiology.
The economic impact of chronic prostatitis.
Calhoun, Elizabeth A; McNaughton Collins, Mary; Pontari, Michel A; O'Leary, Michael; Leiby, Benjamin E; Landis, J Richard; Kusek, John W; Litwin, Mark S
2004-06-14
Little information exists on the economic impact of chronic prostatitis. The objective of this study was to determine the direct and indirect costs associated with chronic prostatitis. Outcomes were assessed using a questionnaire designed to capture health care resource utilization. Resource estimates were converted into unit costs with direct medical cost estimates based on hospital cost-accounting data and indirect costs based on modified labor force, employment, and earnings data from the US Census Bureau. The total direct costs for the 3 months prior to entry into the cohort, excluding hospitalization, were $126 915 for the 167 study participants for an average of $954 per person among the 133 consumers. Of the men, 26% reported work loss valued at an average of $551. The average total costs (direct and indirect) for the 3 months was $1099 per person for those 137 men who had resource consumption with an expected annual total cost per person of $4397. For those study participants with any incurred costs, tests for association revealed that the National Institutes of Health Chronic Prostatitis Symptom Index (P<.001) and each of the 3 subcategories of pain (P =.003), urinary function (P =.03), and quality-of-life (P =.002) were significantly associated with resource use, although the quality-of-life subscale score from the National Institutes of Health Chronic Prostatitis Symptom Index was the only predictor of resource consumption. Chronic prostatitis is associated with substantial costs and lower quality-of-life scores, which predicted resource consumption. The economic impact of chronic prostatitis warrants increased medical attention and resources to identify and test effective treatment strategies.
Careful assessment key in managing prostatitis.
Gujadhur, Rahul; Aning, Jonathan
2015-04-01
Prostatitis is a common condition estimated to affect up to 30% of men in their lifetime, it is most prevalent in men aged between 35 and 50. Prostatitis is subclassified into: acute bacterial prostatitis, chronic bacterial prostatitis, chronic pelvic pain and asymptomatic inflammatory prostatitis. Acute bacterial prostatitis presents with acute onset pelvic pain which may or may not be related to voiding, lower urinary tract symptoms, sometimes haematuria or haematospermia and systemic symptoms such as fever and rigors. A documented history of recurrent urinary tract infections is the key feature of chronic bacterial prostatitis. Duration of symptoms > 3 months defines chronicity. The key symptom of chronic pelvic pain syndrome is pain. Patients may describe pain during or after ejaculation as their predominant symptom. Clinical assessment includes a thorough history and examination. A digital rectal examination should be performed after a midstream urine (MSU) sample has been collected for urine dipstick, microscopy and culture. The prostate should be checked for nodules. In acute bacterial prostatitis the MSU is the only laboratory investigation required. Chronic pelvic pain syndrome may be multifactorial and part of a more generalised pain disorder. Pelvic floor muscle abnormalities, altered neuroendocrine pathways, chemically induced inflammation, bacterial infection, autoimmune processes, dysfunctional voiding as well intraprostatic ductal reflux mechanisms have all been identified in men with chronic pelvic pain syndrome.
Russo, A; Autelitano, M; Bellini, A; Bisanti, L
2002-01-01
The use of the prostate specific antigen (PSA) test in the period 1999-2000 in a population of 311 822 men, aged 40 years or more, resident in Milan, Italy, was examined. Data were drawn from the outpatient database of the local health information system. A total of 139 350 PSA tests were used in 83 943 subjects. Overall, 26.9% of the male population aged 40 or older, with no history of prostate cancer, received a PSA test in the 2 year study period. For subjects older than 50 the rate rose to 34%. Results show a high coverage of the male population in northern Italy with screening using the PSA test for prostate cancer.
Trajectories of Delinquency among Puerto Rican Children and Adolescents at Two Sites
ERIC Educational Resources Information Center
Maldonado-Molina, Mildred M.; Piquero, Alex R.; Jennings, Wesley G.; Bird, Hector; Canino, Glorisa
2009-01-01
This study examined the trajectories of delinquency among Puerto Rican children and adolescents in two cultural contexts. Relying on data from the Boricua Youth Study, a longitudinal study of children and youth from Bronx, New York, and San Juan, Puerto Rico, a group-based trajectory procedure estimated the number of delinquency trajectories,…
Acute Bacterial Prostatitis: Diagnosis and Management.
Coker, Timothy J; Dierfeldt, Daniel M
2016-01-15
Acute bacterial prostatitis is an acute infection of the prostate gland that causes pelvic pain and urinary tract symptoms, such as dysuria, urinary frequency, and urinary retention, and may lead to systemic symptoms, such as fevers, chills, nausea, emesis, and malaise. Although the true incidence is unknown, acute bacterial prostatitis is estimated to comprise approximately 10% of all cases of prostatitis. Most acute bacterial prostatitis infections are community acquired, but some occur after transurethral manipulation procedures, such as urethral catheterization and cystoscopy, or after transrectal prostate biopsy. The physical examination should include abdominal, genital, and digital rectal examination to assess for a tender, enlarged, or boggy prostate. Diagnosis is predominantly made based on history and physical examination, but may be aided by urinalysis. Urine cultures should be obtained in all patients who are suspected of having acute bacterial prostatitis to determine the responsible bacteria and its antibiotic sensitivity pattern. Additional laboratory studies can be obtained based on risk factors and severity of illness. Radiography is typically unnecessary. Most patients can be treated as outpatients with oral antibiotics and supportive measures. Hospitalization and broad-spectrum intravenous antibiotics should be considered in patients who are systemically ill, unable to voluntarily urinate, unable to tolerate oral intake, or have risk factors for antibiotic resistance. Typical antibiotic regimens include ceftriaxone and doxycycline, ciprofloxacin, and piperacillin/tazobactam. The risk of nosocomial bacterial prostatitis can be reduced by using antibiotics, such as ciprofloxacin, before transrectal prostate biopsy.
Pan, Jiahua; Xue, Wei; Sha, Jianjun; Yang, Hu; Xu, Fan; Xuan, Hanqing; Li, Dong; Huang, Yiran
2014-01-01
To evaluate the incidence and the clinicopathological features of incidental prostate cancer detected in radical cystoprostatectomy (RCP) specimens in Chinese men and to estimate the oncological risk of prostate apex-sparing surgery for such patients. The clinical data and pathological feature of 504 patients who underwent RCP for bladder cancer from January 1999 to March 2013 were retrospectively reviewed. Whole mount serial section of the RCP specimens were cut transversely at 3-4 mm intervals and examined in same pathological institution. Thirty-four out of 504 patients (6.8%) had incidental prostate cancer with a mean age of 70.3 years. 12 cases (35.2%) were diagnosed as significant disease. 4 cases were found to have apex involvement of adenocarcinoma of the prostate while in 5 cases the prostate stroma invasion by urothelial carcinoma were identified (one involved prostate apex). The mean follow-up time was 46.4±33.8 months. Biochemical recurrence occurred in 3 patients but no prostate cancer-related death during the follow-up. There was no statistical significance in cancer specific survival between the clinically significant and insignificant cancer group. The prevalence of incidental prostate cancer in RCP specimens in Chinese patients was remarkably lower than in western people. Most of the incidental prostate cancer was clinically insignificant and patient's prognosis was mainly related to the bladder cancer. Sparing the prostate apex was potentially associated with a 1.0% risk of leaving significant cancer of the prostate or urothelial carcinoma.
2014-01-01
Background The role of lycopene in prostate cancer prevention remains controversial. We examined the associations between dietary lycopene intake and prostate cancer, paying particular attention to the influence of prostate-specific antigen screening, and evaluated tissue biomarkers in prostate cancers in relation to lycopene intake. Methods Among 49898 male health professionals, we obtained dietary information through questionnaires and ascertained total and lethal prostate cancer cases from 1986 through January 31, 2010. Cox regression was used to estimate multivariable hazard ratios (HRs) and 95% confidence intervals (CIs). Tissue microarrays and immunohistochemistry were used to assess tumor biomarker expression in a subset of men. Two-sided χ2 tests were used to calculate the P values. Results Higher lycopene intake was inversely associated with total prostate cancer and more strongly with lethal prostate cancer (top vs bottom quintile: HR = 0.72; 95% CI = 0.56 to 0.94; P trend = .04). In a restricted population of screened participants, the inverse associations became markedly stronger (for lethal prostate cancer: HR = 0.47; 95% CI = 0.29 to 0.75; P trend = .009). Comparing different measures of dietary lycopene, early intake, but not recent intake, was inversely associated with prostate cancer. Higher lycopene intake was associated with biomarkers in the cancer indicative of less angiogenic potential. Conclusions Dietary intake of lycopene was associated with reduced risk of lethal prostate cancer and with a lesser degree of angiogenesis in the tumor. Because angiogenesis is a strong progression factor, an endpoint of lethal prostate cancer may be more relevant than an endpoint of indolent prostate cancer for lycopene in the era of highly prevalent prostate-specific antigen screening. PMID:24463248
NASA Astrophysics Data System (ADS)
Striepe, Scott Allen
The objectives of this research were to develop a reconstruction capability using the Program to Optimize Simulated Trajectories II (POST2), apply this capability to reconstruct the Huygens Titan probe entry, descent, and landing (EDL) trajectory, evaluate the newly developed POST2 reconstruction module, analyze the reconstructed trajectory, and assess the pre-flight simulation models used for Huygens EDL simulation. An extended Kalman filter (EKF) module was developed and integrated into POST2 to enable trajectory reconstruction (especially when using POST2-based mission specific simulations). Several validation cases, ranging from a single, constant parameter estimate to multivariable estimation cases similar to an actual mission flight, were executed to test the POST2 reconstruction module. Trajectory reconstruction of the Huygens entry probe at Titan was accomplished using accelerometer measurements taken during flight to adjust an estimated state (e.g., position, velocity, parachute drag, wind velocity, etc.) in a POST2-based simulation developed to support EDL analyses and design prior to entry. Although the main emphasis of the trajectory reconstruction was to evaluate models used in the NASA pre-entry trajectory simulation, the resulting reconstructed trajectory was also assessed to provide an independent evaluation of the ESA result. Major findings from this analysis include: Altitude profiles from this analysis agree well with other NASA and ESA results but not with Radar data, whereas a scale factor of about 0.93 would bring the radar measurements into compliance with these results; entry capsule aerodynamics predictions (axial component only) were well within 3-sigma bounds established pre-flight for most of the entry when compared to reconstructed values; Main parachute drag of 9% to 19% above ESA model was determined from the reconstructed trajectory; based on the tilt sensor and accelerometer data, the conclusion from this assessment was that the probe was tilted about 10 degrees during the Drogue parachute phase.
Calabro, Finnegan J.; Beardsley, Scott A.; Vaina, Lucia M.
2012-01-01
Estimation of time-to-arrival for moving objects is critical to obstacle interception and avoidance, as well as to timing actions such as reaching and grasping moving objects. The source of motion information that conveys arrival time varies with the trajectory of the object raising the question of whether multiple context-dependent mechanisms are involved in this computation. To address this question we conducted a series of psychophysical studies to measure observers’ performance on time-to-arrival estimation when object trajectory was specified by angular motion (“gap closure” trajectories in the frontoparallel plane), looming (colliding trajectories, TTC) or both (passage courses, TTP). We measured performance of time-to-arrival judgments in the presence of irrelevant motion, in which a perpendicular motion vector was added to the object trajectory. Data were compared to models of expected performance based on the use of different components of optical information. Our results demonstrate that for gap closure, performance depended only on the angular motion, whereas for TTC and TTP, both angular and looming motion affected performance. This dissociation of inputs suggests that gap closures are mediated by a separate mechanism than that used for the detection of time-to-collision and time-to-passage. We show that existing models of TTC and TTP estimation make systematic errors in predicting subject performance, and suggest that a model which weights motion cues by their relative time-to-arrival provides a better account of performance. PMID:22056519
Martorana, Eugenio; Pirola, Giacomo Maria; Scialpi, Michele; Micali, Salvatore; Iseppi, Andrea; Bonetti, Luca Reggiani; Kaleci, Shaniko; Torricelli, Pietro; Bianchi, Giampaolo
2017-07-01
To demonstrate the association between magnetic resonance imaging (MRI) estimated lesion volume (LV), prostate cancer detection and tumour clinical significance, evaluating this variable alone and matched with Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score. We retrospectively analysed 157 consecutive patients, with at least one prior negative systematic prostatic biopsy, who underwent transperineal prostate MRI/ultrasonography fusion-targeted biopsy between January 2014 and February 2016. Suspicious lesions were delineated using a 'region of interest' and the system calculated prostate volume and LV. Patients were divided in groups considering LV (≤0.5, 0.5-1, ≥1 mL) and PI-RADS score (1-5). We considered clinically significant prostate cancer as all cancers with a Gleason score of ≥3 + 4 as suggested by PI-RADS v2. A direct comparison between MRI estimated LV (MRI LV) and histological tumour volume (HTV) was done in 23 patients who underwent radical prostatectomy during the study period. Differences between MRI LV and HTV were assessed using the paired sample t-test. MRI LV and HTV concordance was verified using a Bland-Altman plot. The chi-squared test and logistic and ordinal regression models were used to evaluate difference in frequencies. The MRI LV and PI-RADS score were associated both with prostate cancer detection (both P < 0.001) and with significant prostate cancer detection (P < 0.001 and P = 0.008, respectively). When the two variables were matched, increasing LV increased the risk within each PI-RADS group. Prostate cancer detection was 1.4-times higher for LVs of 0.5-1 mL and 1.8-times higher for LVs of ≥1 mL; significant prostate cancer detection was 2.6-times for LVs of 0.5-1 mL and 4-times for LVs of ≥1 mL. There was a positive correlation between MRI LV and HTV (r = 0.9876, P < 0.001). Finally, Bland-Altman analysis showed that MRI LV was underestimated by 4.2% compared to HTV. Study limitations include its monocentric and retrospective design and the limited cohort. This study demonstrates that PI-RADS score and the MRI LV, independently and in combination, are associated with prostate cancer detection and with tumour clinical significance. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.
Yeboah, E D
2016-01-01
There have been several publications on population or community prevalence of benign prostatic hyperplasia and prostate cancer from various countries and races but few reports are from Africa on Africans. A review on the prevalence of benign prostatic hyperplasia and prostate cancer in Africans and other races. The current literature on prevalence of benign prostatic hyperplasia (BPH), prostate cancer (PC), and benign prostatic hyperplasia co-existing with prostate cancer in Africans and other races is reviewed. Benign prostatic hyperplasia (BPH) prevalence in Ghana is responsible for 60% acute retention of urine and 28.6% of haematuria. Worldwide prevalence of BPH varies from 20 - 62% in men over 50 years and this includes USA, UK, Japan and Ghana. Reports from South Africa indicate prevalence of over 50% in adult males of 60 years. BPH co-existing with PC - Reports from USA, UK and Japan and Ghana reveal moderate association of BPH and PC. The co-existence of PC in patients being treated for BPH is 3 - 20% Prostate Cancer prevalence - There is high prevalence in USA, Scandinavian Countries, African Americans (AA) and Caribbean blacks. Ghana, Trinidad & Tobago have reported high prevalence of 6 -10% in men aged 50 years and above but others reported low prevalence in Africans from Africa. The low reporting from Africa of 10 - 40:100,000 is attributable to under reporting, absence of PSA screening/testing, lack of reliable cancer registries and poor medical facilities. Economic Costs of BPH and PC: BPH in the USA national direct costs are estimated at U$4Billion and individual costs of US$1536 annually. In Ghana, individual costs for BPH medications range from US$300 - 550 per year and cost for simple prostatectomy/TURP is estimated at US$1100. For prostate cancer, individual direct costs from Europe range from 6,575 - 12,000 euros, £2818.00 UK and over U$12,000 - 20,000 in USA per annum. In Ghana, individual direct costs ranges, for radical prostatectomy and external beam radiotherapy US$1250 - 1500, for brachytherapy 9,000 Euros, for hormonal therapy US$1600 - 3200) per year and US$510 for orchidectomy. Recent evidence although sparse indicate there is high prevalence of BPH and PC in Africans and men of African descent in diaspora, the low prevalence of BPH and PC reported from some African countries is likely to under reporting and future prevalence studies both in the living and deceased are recommended to reveal the true prevalence of BPH and PC in Africans though screening for PC in the living remains controversial.
2011-01-01
Background Readthrough fusions across adjacent genes in the genome, or transcription-induced chimeras (TICs), have been estimated using expressed sequence tag (EST) libraries to involve 4-6% of all genes. Deep transcriptional sequencing (RNA-Seq) now makes it possible to study the occurrence and expression levels of TICs in individual samples across the genome. Methods We performed single-end RNA-Seq on three human prostate adenocarcinoma samples and their corresponding normal tissues, as well as brain and universal reference samples. We developed two bioinformatics methods to specifically identify TIC events: a targeted alignment method using artificial exon-exon junctions within 200,000 bp from adjacent genes, and genomic alignment allowing splicing within individual reads. We performed further experimental verification and characterization of selected TIC and fusion events using quantitative RT-PCR and comparative genomic hybridization microarrays. Results Targeted alignment against artificial exon-exon junctions yielded 339 distinct TIC events, including 32 gene pairs with multiple isoforms. The false discovery rate was estimated to be 1.5%. Spliced alignment to the genome was less sensitive, finding only 18% of those found by targeted alignment in 33-nt reads and 59% of those in 50-nt reads. However, spliced alignment revealed 30 cases of TICs with intervening exons, in addition to distant inversions, scrambled genes, and translocations. Our findings increase the catalog of observed TIC gene pairs by 66%. We verified 6 of 6 predicted TICs in all prostate samples, and 2 of 5 predicted novel distant gene fusions, both private events among 54 prostate tumor samples tested. Expression of TICs correlates with that of the upstream gene, which can explain the prostate-specific pattern of some TIC events and the restriction of the SLC45A3-ELK4 e4-e2 TIC to ERG-negative prostate samples, as confirmed in 20 matched prostate tumor and normal samples and 9 lung cancer cell lines. Conclusions Deep transcriptional sequencing and analysis with targeted and spliced alignment methods can effectively identify TIC events across the genome in individual tissues. Prostate and reference samples exhibit a wide range of TIC events, involving more genes than estimated previously using ESTs. Tissue specificity of TIC events is correlated with expression patterns of the upstream gene. Some TIC events, such as MSMB-NCOA4, may play functional roles in cancer. PMID:21261984
Depaoli, Sarah; van de Schoot, Rens; van Loey, Nancy; Sijbrandij, Marit
2015-01-01
After traumatic events, such as disaster, war trauma, and injuries including burns (which is the focus here), the risk to develop posttraumatic stress disorder (PTSD) is approximately 10% (Breslau & Davis, 1992). Latent Growth Mixture Modeling can be used to classify individuals into distinct groups exhibiting different patterns of PTSD (Galatzer-Levy, 2015). Currently, empirical evidence points to four distinct trajectories of PTSD patterns in those who have experienced burn trauma. These trajectories are labeled as: resilient, recovery, chronic, and delayed onset trajectories (e.g., Bonanno, 2004; Bonanno, Brewin, Kaniasty, & Greca, 2010; Maercker, Gäbler, O'Neil, Schützwohl, & Müller, 2013; Pietrzak et al., 2013). The delayed onset trajectory affects only a small group of individuals, that is, about 4-5% (O'Donnell, Elliott, Lau, & Creamer, 2007). In addition to its low frequency, the later onset of this trajectory may contribute to the fact that these individuals can be easily overlooked by professionals. In this special symposium on Estimating PTSD trajectories (Van de Schoot, 2015a), we illustrate how to properly identify this small group of individuals through the Bayesian estimation framework using previous knowledge through priors (see, e.g., Depaoli & Boyajian, 2014; Van de Schoot, Broere, Perryck, Zondervan-Zwijnenburg, & Van Loey, 2015). We used latent growth mixture modeling (LGMM) (Van de Schoot, 2015b) to estimate PTSD trajectories across 4 years that followed a traumatic burn. We demonstrate and compare results from traditional (maximum likelihood) and Bayesian estimation using priors (see, Depaoli, 2012, 2013). Further, we discuss where priors come from and how to define them in the estimation process. We demonstrate that only the Bayesian approach results in the desired theory-driven solution of PTSD trajectories. Since the priors are chosen subjectively, we also present a sensitivity analysis of the Bayesian results to illustrate how to check the impact of the prior knowledge integrated into the model. We conclude with recommendations and guidelines for researchers looking to implement theory-driven LGMM, and we tailor this discussion to the context of PTSD research.
NASA Astrophysics Data System (ADS)
Rühs, Siren; Zhurbas, Victor; Durgadoo, Jonathan V.; Biastoch, Arne
2017-04-01
The Lagrangian description of fluid motion by sets of individual particle trajectories is extensively used to characterize connectivity between distinct oceanic locations. One important factor influencing the connectivity is the average rate of particle dispersal, generally quantified as Lagrangian diffusivity. In addition to Lagrangian observing programs, Lagrangian analyses are performed by advecting particles with the simulated flow field of ocean general circulation models (OGCMs). However, depending on the spatio-temporal model resolution, not all scale-dependent processes are explicitly resolved in the simulated velocity fields. Consequently, the dispersal of advective Lagrangian trajectories has been assumed not to be sufficiently diffusive compared to observed particle spreading. In this study we present a detailed analysis of the spatially variable lateral eddy diffusivity characteristics of advective drifter trajectories simulated with realistically forced OGCMs and compare them with estimates based on observed drifter trajectories. The extended Agulhas Current system around South Africa, known for its intricate mesoscale dynamics, serves as a test case. We show that a state-of-the-art eddy-resolving OGCM indeed features theoretically derived dispersion characteristics for diffusive regimes and realistically represents Lagrangian eddy diffusivity characteristics obtained from observed surface drifter trajectories. The estimates for the maximum and asymptotic lateral single-particle eddy diffusivities obtained from the observed and simulated drifter trajectories show a good agreement in their spatial pattern and magnitude. We further assess the sensitivity of the simulated lateral eddy diffusivity estimates to the temporal and lateral OGCM output resolution and examine the impact of the different eddy diffusivity characteristics on the Lagrangian connectivity between the Indian Ocean and the South Atlantic.
MARS Science Laboratory Post-Landing Location Estimation Using Post2 Trajectory Simulation
NASA Technical Reports Server (NTRS)
Davis, J. L.; Shidner, Jeremy D.; Way, David W.
2013-01-01
The Mars Science Laboratory (MSL) Curiosity rover landed safely on Mars August 5th, 2012 at 10:32 PDT, Earth Received Time. Immediately following touchdown confirmation, best estimates of position were calculated to assist in determining official MSL locations during entry, descent and landing (EDL). Additionally, estimated balance mass impact locations were provided and used to assess how predicted locations compared to actual locations. For MSL, the Program to Optimize Simulated Trajectories II (POST2) was the primary trajectory simulation tool used to predict and assess EDL performance from cruise stage separation through rover touchdown and descent stage impact. This POST2 simulation was used during MSL operations for EDL trajectory analyses in support of maneuver decisions and imaging MSL during EDL. This paper presents the simulation methodology used and results of pre/post-landing MSL location estimates and associated imagery from Mars Reconnaissance Orbiter s (MRO) High Resolution Imaging Science Experiment (HiRISE) camera. To generate these estimates, the MSL POST2 simulation nominal and Monte Carlo data, flight telemetry from onboard navigation, relay orbiter positions from MRO and Mars Odyssey and HiRISE generated digital elevation models (DEM) were utilized. A comparison of predicted rover and balance mass location estimations against actual locations are also presented.
Conflict Probability Estimation for Free Flight
NASA Technical Reports Server (NTRS)
Paielli, Russell A.; Erzberger, Heinz
1996-01-01
The safety and efficiency of free flight will benefit from automated conflict prediction and resolution advisories. Conflict prediction is based on trajectory prediction and is less certain the farther in advance the prediction, however. An estimate is therefore needed of the probability that a conflict will occur, given a pair of predicted trajectories and their levels of uncertainty. A method is developed in this paper to estimate that conflict probability. The trajectory prediction errors are modeled as normally distributed, and the two error covariances for an aircraft pair are combined into a single equivalent covariance of the relative position. A coordinate transformation is then used to derive an analytical solution. Numerical examples and Monte Carlo validation are presented.
2013-05-01
for initial test of object coverage for these scanning trajectories. I have also acquired real data of physical phantoms by using a clinical CBCT system...scan. To test the extension of axial coverage, I car- ried out a simulated data study using numerical disk and anthropomorphic XCAT phantoms [15]. As an...imaging model in Eq. (1), I investigated the choice of data divergence, such as the Euclidean distance or Kullback - Leibler (K-L) divergence, which are
Hirasawa, Yosuke; Ohno, Yoshio; Nakashima, Jun; Shimodaira, Kenji; Hashimoto, Takeshi; Gondo, Tatsuo; Ohori, Makoto; Tachibana, Masaaki; Yoshioka, Kunihiko
2016-09-01
To assess the impact of preoperatively estimated prostate volume (PV) using transrectal ultrasonography (TRUS) on surgical and oncological outcomes in robot-assisted radical prostatectomy (RARP). We analyzed the experience of a single surgeon at our hospital who performed 436 RARPs without neoadjuvant hormone therapy between August 2006 and December 2013. Patients were divided into three groups according to their preoperative PV calculated using TRUS (PV ≤ 20 cm(3): group 1, n = 61; 20 < PV < 50 cm(3): group 2, n = 303; PV ≥ 50 cm(3): group 3, n = 72). Blood loss was significantly higher in group 3 than in group 1 and group 2. In stage pT2 patients, the rate of positive surgical margin (PSM) was significantly lower in group 3 than in group 1. In addition, perioperative complications significantly increased with increasing PV, while the extraprostatic extension (EPE) rate significantly decreased with increasing PV. The preoperative biopsy Gleason score, prostate-specific antigen (PSA) density, and clinical T2 stage were inversely correlated with increasing PV. Biochemical recurrence-free survival after RARP was significantly lower in group 1 than in groups 2 and 3. A large prostate size was significantly associated with increased blood loss and a higher rate of perioperative complications. A small prostate size was associated with a higher PSM rate, PSA density, Gleason score, EPE rate, and biochemical recurrence rate. These results suggest that RARP was technically challenging in patients with large prostates, whereas small prostates were associated with unfavorable oncological outcomes.
Carlsson, Sigrid V; Peltola, Mari T; Sjoberg, Daniel; Schröder, Fritz H; Hugosson, Jonas; Pettersson, Kim; Scardino, Peter T; Vickers, Andrew J; Lilja, Hans; Roobol, Monique J
2013-09-01
To explore whether a panel of kallikrein markers in blood: total, free and intact prostate-specific antigen (PSA) and kallikrein-related peptidase 2, could be used as a non-invasive alternative for predicting prostate cancer on biopsy in a screening setting. The study cohort comprised previously unscreened men who underwent sextant biopsy owing to elevated PSA (≥3 ng/mL) in two different centres of the European Randomized Study of Screening for Prostate Cancer, Rotterdam (n = 2914) and Göteborg (n = 740). A statistical model, based on kallikrein markers, was compared with one based on established clinical factors for the prediction of biopsy outcome. The clinical tests were found to be no better than blood markers, with an area under the curve in favour of the blood measurements of 0.766 vs. 0.763 in Rotterdam and 0.809 vs. 0.774 in Göteborg. Adding digital rectal examination (DRE) or DRE plus transrectal ultrasonography (TRUS) volume to the markers improved discrimination, although the increases were small. Results were similar for predicting high-grade cancer. There was a strong correlation between the blood measurements and TRUS-estimated prostate volume (Spearman's correlation 0.60 in Rotterdam and 0.57 in Göteborg). In previously unscreened men, each with indication for biopsy, a statistical model based on kallikrein levels was similar to a clinical model in predicting prostate cancer in a screening setting, outside the day-to-day clinical practice. Whether a clinical approach can be replaced by laboratory analyses or used in combination with decision models (nomograms) is a clinical judgment that may vary from clinician to clinician depending on how they weigh the different advantages and disadvantages (harms, costs, time, invasiveness) of both approaches. © 2013 BJU International.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khalvati, Farzad, E-mail: farzad.khalvati@uwaterloo.ca; Tizhoosh, Hamid R.; Salmanpour, Aryan
Purpose: Accurate segmentation and volume estimation of the prostate gland in magnetic resonance (MR) and computed tomography (CT) images are necessary steps in diagnosis, treatment, and monitoring of prostate cancer. This paper presents an algorithm for the prostate gland volume estimation based on the semiautomated segmentation of individual slices in T2-weighted MR and CT image sequences. Methods: The proposedInter-Slice Bidirectional Registration-based Segmentation (iBRS) algorithm relies on interslice image registration of volume data to segment the prostate gland without the use of an anatomical atlas. It requires the user to mark only three slices in a given volume dataset, i.e., themore » first, middle, and last slices. Next, the proposed algorithm uses a registration algorithm to autosegment the remaining slices. We conducted comprehensive experiments to measure the performance of the proposed algorithm using three registration methods (i.e., rigid, affine, and nonrigid techniques). Results: The results with the proposed technique were compared with manual marking using prostate MR and CT images from 117 patients. Manual marking was performed by an expert user for all 117 patients. The median accuracies for individual slices measured using the Dice similarity coefficient (DSC) were 92% and 91% for MR and CT images, respectively. The iBRS algorithm was also evaluated regarding user variability, which confirmed that the algorithm was robust to interuser variability when marking the prostate gland. Conclusions: The proposed algorithm exploits the interslice data redundancy of the images in a volume dataset of MR and CT images and eliminates the need for an atlas, minimizing the computational cost while producing highly accurate results which are robust to interuser variability.« less
Kim, Fernando J; Cerqueira, Michael A; Almeida, Jose C; Pompeo, Alexandre; Sehrt, David; Calheiros, Jose M; Martins, Fernando A; Molina, Wilson R
2012-01-01
The objective of our study is to present the first Brazilian cryoablation experience in the treatment of low and intermediate risk localized prostate cancer using 3rd generation cryoablation and real-time biplanar transrectal ultrasonography. Ten Brazilian patients underwent primary cryoablation for localized prostate cancer between October 2010 and June 2011. All patients consented for whole gland primary cryotherapy. The procedures were performed by 3rd generation cryoablation with the Cryocare System ® (Endocare, Irvine, California). Preoperative data collection included patient demographics along with prostate gland size, Gleason score, serum prostate specific antigen, and erectile function status. Operative and post--operative assessment involved estimated blood loss, operative time, complications, serum PSA level, erectile function status, urinary incontinence, biochemical disease free survival (BDFS), and follow-up time. All patients in the study successfully underwent whole gland cryoablation. The mean of: age, prostate size, PSA level, and Gleason score, was 66.2 years old; 40.7 g; 7.8 ng/mL; and 6 respectively. All patients were classified as low or moderate D' Amico risk (5 low and 5 moderate). Erectile dysfunction was present in 50% of patients. The estimated blood loss was minimal, operative time was 46.1 minutes. All patients that developed erectile dysfunction post-treatment responded to oral or intracavernosal medications with early penile rehabilitation. All patients maintained urinary continence by the end of a 10 months evaluation period and none had biochemical relapse within the mean follow-up of 13 months (7-15 months). Our initial experience shows that cryoablation is a minimally invasive option for the treatment of localized prostate cancer. Short term data seems to be promising but longer follow-up is necessary to verify oncological and functional results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khalvati, Farzad, E-mail: farzad.khalvati@uwaterloo.ca; Tizhoosh, Hamid R.; Salmanpour, Aryan
2013-12-15
Purpose: Accurate segmentation and volume estimation of the prostate gland in magnetic resonance (MR) and computed tomography (CT) images are necessary steps in diagnosis, treatment, and monitoring of prostate cancer. This paper presents an algorithm for the prostate gland volume estimation based on the semiautomated segmentation of individual slices in T2-weighted MR and CT image sequences. Methods: The proposedInter-Slice Bidirectional Registration-based Segmentation (iBRS) algorithm relies on interslice image registration of volume data to segment the prostate gland without the use of an anatomical atlas. It requires the user to mark only three slices in a given volume dataset, i.e., themore » first, middle, and last slices. Next, the proposed algorithm uses a registration algorithm to autosegment the remaining slices. We conducted comprehensive experiments to measure the performance of the proposed algorithm using three registration methods (i.e., rigid, affine, and nonrigid techniques). Results: The results with the proposed technique were compared with manual marking using prostate MR and CT images from 117 patients. Manual marking was performed by an expert user for all 117 patients. The median accuracies for individual slices measured using the Dice similarity coefficient (DSC) were 92% and 91% for MR and CT images, respectively. The iBRS algorithm was also evaluated regarding user variability, which confirmed that the algorithm was robust to interuser variability when marking the prostate gland. Conclusions: The proposed algorithm exploits the interslice data redundancy of the images in a volume dataset of MR and CT images and eliminates the need for an atlas, minimizing the computational cost while producing highly accurate results which are robust to interuser variability.« less
Prostate cancer burden in Central and South America.
Sierra, Mónica S; Soerjomataram, Isabelle; Forman, David
2016-09-01
The incidence of prostate cancer has increased in Central and South America (CSA) in the last few decades. We describe the geographical patterns and trends of prostate cancer in CSA. We obtained regional and national-level cancer incidence data from 48 population-based registries in 13 countries and nation-wide cancer deaths from the WHO mortality database for 18 countries. We estimated world population age-standardized incidence (ASR) and mortality (ASMR) rates per 100,000 person-years for 2003-2007 and the estimated annual percent change (EAPC) to describe time trends. Prostate cancer was the most common cancer diagnosis and one of the leading causes of cancer deaths among males in most CSA countries. From 2003-2007, ASRs varied between countries (6-fold) and within countries (Brazil: 3-6-fold). French Guyana (147.1) and Brazil (91.4) had the highest ASRs whereas Mexico (28.9) and Cuba (24.3) had the lowest. ASMRs varied by 4-fold. Belize, Uruguay and Cuba (24.1-28.9) had the highest ASMRs while Peru, Nicaragua, and El Salvador (6.8-9.7) had the lowest. In Argentina, Brazil, Chile and Costa Rica prostate cancer incidence increased by 2.8-4.8% annually whereas mortality remained stable between 1997 and 2008. The geographic and temporal variation of prostate cancer rates observed in CSA may in part reflect differences in diagnostic and registration practices, healthcare access, treatment and death certification, and public awareness. The incidence of prostate cancer is expected to increase given recent early detection activities and increased public awareness; however, the impact of these factors on mortality remains to be elucidated. Copyright © 2016 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.
Duboureau, H; Achkar, K; Stephan, R; Schmit, J L; Saint, F
2017-05-01
The biopsies of prostate are the reference examination to assert the diagnosis of prostate cancer. Even if the urinary infectious complications are rare thanks to the systematic oral antibiotic prophylaxis, they may still be serious. The SPILF (Society of Infectious Pathology and French language) published in 2014, an important increase of the resistances in fluoroquinolones for Escherichia coli (3 to 25%), whereas this is the most bacterium frequently found in the urinary infections (70-80%). The objectives of this study were to estimate the indicence of the febrile urinary tract infections after prostate needle biopsy and to define the ecology and the profile of E. coli's resistance. A total of 466 transrectal ultrasound-guided needle prostate biopsy were included in the study from 2012 to 2015. All the patients were taken care according to the recommendations of the AFU (Ouzzane et al., 2011). We estimated, for all the inclusive patients, if they had presented a clinic sign of urinary infection like fever or burning which suggestive of an urinary infection, and having a urines and blood culture, in the next 30 days the realization of the medical exam. Among 466 realized biopsies, seven patients developed a febril urinary tract infection (1.5%) [prostatitis (n=6), orchitis (n=1)]. Five infections to E. coli were identified; two were resistant for fluoroquinolones (40%). No germ was able to be identified for two patients. The infectious complications post-biopsy of prostate are rare (1.5%). E. coli is the germ most frequently identified with 40% of resistance with fluoroquinolones. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Corbett, Elaine A; Perreault, Eric J; Körding, Konrad P
2012-06-01
Neuroprosthetic devices promise to allow paralyzed patients to perform the necessary functions of everyday life. However, to allow patients to use such tools it is necessary to decode their intent from neural signals such as electromyograms (EMGs). Because these signals are noisy, state of the art decoders integrate information over time. One systematic way of doing this is by taking into account the natural evolution of the state of the body--by using a so-called trajectory model. Here we use two insights about movements to enhance our trajectory model: (1) at any given time, there is a small set of likely movement targets, potentially identified by gaze; (2) reaches are produced at varying speeds. We decoded natural reaching movements using EMGs of muscles that might be available from an individual with spinal cord injury. Target estimates found from tracking eye movements were incorporated into the trajectory model, while a mixture model accounted for the inherent uncertainty in these estimates. Warping the trajectory model in time using a continuous estimate of the reach speed enabled accurate decoding of faster reaches. We found that the choice of richer trajectory models, such as those incorporating target or speed, improves decoding particularly when there is a small number of EMGs available.
Hill, Terrence D.; Uchino, Bert N.; Eckhardt, Jessica L.; Angel, Jacqueline L.
2016-01-01
Although numerous studies of non-Hispanic whites and blacks show that social integration and social support tend to favor longevity, it is unclear whether this general pattern extends to the Mexican American population. Building on previous research, we employed seven waves of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to examine the association between perceived social support trajectories and the all-cause mortality risk of older Mexican Americans. Growth mixture estimates revealed three latent classes of support trajectories: high, moderate, and low. Cox regression estimates indicated that older Mexican American men in the low support trajectory tend to exhibit a higher mortality risk than their counterparts in the high support trajectory. Social support trajectories were unrelated to the mortality risk of older Mexican American women. A statistically significant interaction term confirmed that social support was more strongly associated with the mortality risk of men. PMID:26966256
Hill, Terrence D; Uchino, Bert N; Eckhardt, Jessica L; Angel, Jacqueline L
2016-04-01
Although numerous studies of non-Hispanic Whites and Blacks show that social integration and social support tend to favor longevity, it is unclear whether this general pattern extends to the Mexican American population. Building on previous research, we employed seven waves of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to examine the association between perceived social support trajectories and the all-cause mortality risk of older Mexican Americans. Growth mixture estimates revealed three latent classes of support trajectories: high, moderate, and low. Cox regression estimates indicated that older Mexican American men in the low support trajectory tend to exhibit a higher mortality risk than their counterparts in the high support trajectory. Social support trajectories were unrelated to the mortality risk of older Mexican American women. A statistically significant interaction term confirmed that social support was more strongly associated with the mortality risk of men. © The Author(s) 2015.
Body mass index influences prostate cancer risk at biopsy in Japanese men.
Masuda, Hitoshi; Kagawa, Makoto; Kawakami, Satoru; Numao, Noboru; Matsuoka, Yoh; Yokoyama, Minato; Yamamoto, Shinya; Yonese, Junji; Fukui, Iwao; Kihara, Kazunori
2013-07-01
To determine the relationship between body mass index and prostate cancer risk at biopsy in Japanese men, and to compared the risk with that of Caucasian men. We retrospectively evaluated 3966 men with prostate-specific antigen levels from 2.5 to 19.9 ng/mL who underwent an initial extended prostate biopsy. Using logistic regression, odds ratios of each body mass index category for risk of prostate cancer and high-grade disease (Gleason score ≥4 + 3) were estimated after controlling for age, prostate-specific antigen, %free prostate-specific antigen, prostate volume, digital rectal examination findings, family history of prostate cancer and the number of biopsy cores. Patients were divided into six categories according to their body mass index (kg/m(2) ) as follows: <21.0, 21.0-22.9, 23.0-24.9, 25.0-26.9, 27.0-29.9 and ≥30.0. A significant positive association was observed between body mass index and prostate cancer risk at biopsy, with an increased risk observed in men whose body mass index was ≥27.0 compared with the reference group. A significantly increased risk starting at body mass index ≥25.0 was found in high-grade disease. In contrast to our results, there has been no reported increase in the risk of prostate cancer at biopsy in Caucasians within the overweight range (body mass index of 25.0-29.9 based on World Health Organization classification). Japanese men within the overweight body mass index range who have an elevated prostate-specific antigen level also have a significant risk of harboring prostate cancer, especially high-grade disease. Overweight Japanese might be at greater prostate cancer risk at biopsy than overweight Caucasians. © 2012 The Japanese Urological Association.
Technology diffusion and diagnostic testing for prostate cancer.
Schroeck, Florian R; Kaufman, Samuel R; Jacobs, Bruce L; Skolarus, Ted A; Miller, David C; Weizer, Alon Z; Montgomery, Jeffrey S; Wei, John T; Shahinian, Vahakn B; Hollenbeck, Brent K
2013-11-01
While the dissemination of robotic prostatectomy and intensity modulated radiotherapy may fuel the increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with the receipt of prostate specific antigen testing and prostate biopsy. In this retrospective cohort study we included 117,857 men 66 years old or older from the 5% sample of Medicare beneficiaries living in Surveillance, Epidemiology and End Results (SEER) areas from 2003 to 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or intensity modulated radiotherapy per population in a health care market, ie hospital referral region. We assessed the association of technology penetration with the prostate specific antigen testing rate and prostate biopsy using generalized estimating equations. High technology penetration was associated with an increased rate of prostate specific antigen testing (442 vs 425/1,000 person-years, p<0.01) and a similar rate of prostate biopsy (10.1 vs 9.9/1,000 person-years, p=0.69). The impact of technology penetration on prostate specific antigen testing and prostate biopsy was much less than the effect of age, race and comorbidity, eg the prostate specific antigen testing rate per 1,000 person-years was 485 vs 373 for men with only 1 vs 3+ comorbid conditions (p<0.01). Increased technology penetration is associated with a slightly higher rate of prostate specific antigen testing and no change in the prostate biopsy rate. Collectively, our findings temper concerns that adopting new technology accelerates diagnostic testing for prostate cancer. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Estimation of Center of Mass Trajectory using Wearable Sensors during Golf Swing
Najafi, Bijan; Lee-Eng, Jacqueline; Wrobel, James S.; Goebel, Ruben
2015-01-01
This study suggests a wearable sensor technology to estimate center of mass (CoM) trajectory during a golf swing. Groups of 3, 4, and 18 participants were recruited, respectively, for the purpose of three validation studies. Study 1 examined the accuracy of the system to estimate a 3D body segment angle compared to a camera-based motion analyzer (Vicon®). Study 2 assessed the accuracy of three simplified CoM trajectory models. Finally, Study 3 assessed the accuracy of the proposed CoM model during multiple golf swings. A relatively high agreement was observed between wearable sensors and the reference (Vicon®) for angle measurement (r > 0.99, random error <1.2° (1.5%) for anterior-posterior; <0.9° (2%) for medial-lateral; and <3.6° (2.5%) for internal-external direction). The two-link model yielded a better agreement with the reference system compared to one-link model (r > 0.93 v. r = 0.52, respectively). On the same note, the proposed two-link model estimated CoM trajectory during golf swing with relatively good accuracy (r > 0.9, A-P random error <1cm (7.7%) and <2cm (10.4%) for M-L). The proposed system appears to accurately quantify the kinematics of CoM trajectory as a surrogate of dynamic postural control during an athlete’s movement and its portability, makes it feasible to fit the competitive environment without restricting surface type. Key points This study demonstrates that wearable technology based on inertial sensors are accurate to estimate center of mass trajectory in complex athletic task (e.g., golf swing) This study suggests that two-link model of human body provides optimum tradeoff between accuracy and minimum number of sensor module for estimation of center of mass trajectory in particular during fast movements. Wearable technologies based on inertial sensors are viable option for assessing dynamic postural control in complex task outside of gait laboratory and constraints of cameras, surface, and base of support. PMID:25983585
Cowlishaw, Sean; Suomi, Aino; Rodgers, Bryan
2016-09-01
To evaluate (1) whether gambling problems predict overall trajectories of change in family or interpersonal adjustment and (2) whether annual measures of gambling problems predict time-specific decreases in family or interpersonal adjustment, concurrently and prospectively. The Quinte Longitudinal Study (QLS) involved random-digit dialling of telephone numbers around the city of Belleville, Canada to recruit 'general population' and 'at-risk' groups (the latter oversampling people likely to develop problems). Five waves of assessment were conducted (2006-10). Latent Trajectory Modelling (LTM) estimated overall trajectories of family and interpersonal adjustment, which were predicted by gambling problems, and also estimated how time-specific problems predicted deviations from these trajectories. Southeast Ontario, Canada. Community sample of Canadian adults (n = 4121). The Problem Gambling Severity Index (PGSI) defined at-risk gambling (ARG: PGSI 1-2) and moderate-risk/problem gambling (MR/PG: PGSI 3+). Outcomes included: (1) family functioning, assessed using a seven-point rating of overall functioning; (2) social support, assessed using items from the Non-support subscale of the Personality Assessment Inventory; and (3) relationship satisfaction, measured by the Kansas Marital Satisfaction Scale. Baseline measures of ARG and MR/PG did not predict rates of change in trajectories of family or interpersonal adjustment. Rather, the annual measures of MR/PG predicted time-specific decreases in family functioning (estimate: -0.11, P < 0.01), social support (estimate: -0.28, P < 0.01) and relationship satisfaction (estimate: -0.53, P < 0.01). ARG predicted concurrent levels of family functioning (estimate: -0.07, P < 0.01). There were time-lagged effects of MR/PG on subsequent levels of family functioning (estimate: -0.12, P < 0.01) and social support (estimate: -0.24, P < 0.01). In a longitudinal study of Canadian adults, moderate-risk/problem gambling did not predict overall trajectories of family or interpersonal adjustment. Rather, the annual measures of moderate-risk/problem gambling predicted time-specific and concurrent decreases in all outcomes, and lower family functioning and social support across adjacent waves. © 2016 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.
Worldwide Prevalence of Human Papillomavirus and Relative Risk of Prostate Cancer: A Meta-analysis
Yang, Lin; Xie, Shuanghua; Feng, Xiaoshuang; Chen, Yuheng; Zheng, Tongzhang; Dai, Min; Ke Zhou, Cindy; Hu, Zhibin; Li, Ni; Hang, Dong
2015-01-01
Despite the increasing number of studies conducted recently to evaluate the association between HPV infections and the risk of prostate cancer, the results remain inconclusive. Furthermore, the prevalence and distribution of overall and individual HPV types worldwide in prostate cancer has not been reported until now. Therefore, we estimated the prevalence of HPV in prostate cancer by pooling data of 46 studies with 4919 prostate cancer cases, taking into account the heterogeneity of major related parameters, including study region, specimen type, HPV DNA source, detection method, publication calendar period and Gleason score. Moreover, we tested the association of HPV infections with prostate cancer risks by a meta-analysis of 26 tissue-based case-control studies. We found that the prevalence of HPV infection was 18.93% (95% CI = 17.84–20.05%) in prostate cancer cases, and most of which were high-risk HPV types (17.73%, 95% CI = 16.52–18.99%). The prevalence varied by region, PCR primers used, publication calendar period and Gleason score. Our study also showed a significantly increased risk of prostate cancer with the positivity of overall HPV detected in prostate tissues (OR = 1.79, 95% CI = 1.29–2.49) and revealed the geographic variation of association strength (P < 0.001). In conclusion, HPV infections may contribute to the risk of prostate cancer. PMID:26441160
Influence of the number of elongated fiducial markers on the localization accuracy of the prostate
NASA Astrophysics Data System (ADS)
de Boer, Johan; de Bois, Josien; van Herk, Marcel; Sonke, Jan-Jakob
2012-10-01
Implanting fiducial markers for localization purposes has become an accepted practice in radiotherapy for prostate cancer. While many correction strategies correct for translations only, advanced correction protocols also require knowledge of the rotation of the prostate. For this purpose, typically, three or more markers are implanted. Elongated fiducial markers provide more information about their orientation than traditional round or cylindrical markers. Potentially, fewer markers are required. In this study, we evaluate the effect of the number of elongated markers on the localization accuracy of the prostate. To quantify the localization error, we developed a model that estimates, at arbitrary locations in the prostate, the registration error caused by translational and rotational uncertainties of the marker registration. Every combination of one, two and three markers was analysed for a group of 24 patients. The average registration errors at the prostate surface were 0.3-0.8 mm and 0.4-1 mm for registrations on, respectively, three markers and two markers located on different sides of the prostate. Substantial registration errors (2.0-2.2 mm) occurred at the prostate surface contralateral to the markers when two markers were implanted on the same side of the prostate or only one marker was used. In conclusion, there is no benefit in using three elongated markers: two markers accurately localize the prostate if they are implanted at some distance from each other.
Coffee and tea consumption in relation to prostate cancer prognosis
Geybels, Milan S.; Neuhouser, Marian L.; Wright, Jonathan L.; Stott-Miller, Marni; Stanford, Janet L.
2013-01-01
Background Bioactive compounds found in coffee and tea may delay the progression of prostate cancer. Methods We investigated associations of pre-diagnostic coffee and tea consumption with risk of prostate cancer recurrence/progression. Study participants were men diagnosed with prostate cancer in 2002–2005 in King County, Washington, USA. We assessed the usual pattern of coffee and tea consumption two years before diagnosis date. Prostate cancer outcome events were identified using a detailed follow-up survey. Multivariable Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results The analysis of coffee intake in relation to prostate cancer recurrence/progression included 630 patients with a median follow-up of 6.4 years, during which 140 prostate cancer recurrence/progression events were recorded. Approximately 61% of patients consumed at least one cup of coffee per day. Coffee consumption was associated with a reduced risk of prostate cancer recurrence/progression; the adjusted HR for ≥4 cups/day versus ≤1 cup/week was 0.41 (95% CI: 0.20, 0.81; P for trend = 0.01). Approximately 14% of patients consumed one or more cups of tea per day, and tea consumption was unrelated to prostate cancer recurrence/progression. Conclusion Results indicate that pre-diagnostic coffee consumption is associated with a lower risk of prostate cancer recurrence/progression. This finding will require replication in larger studies. PMID:23907772
Vertosick, Emily A; Poon, Bing Ying; Vickers, Andrew J
2014-09-01
Many guidelines suggest earlier screening for prostate cancer in men at high risk, with risk defined in terms of race and family history. Recent evidence suggests that baseline prostate specific antigen is strongly predictive of the long-term risk of aggressive prostate cancer. We compared the usefulness of risk stratifying early screening by race, family history and prostate specific antigen at age 45 years. Using estimates from the literature we calculated the proportion of men targeted for early screening using family history, black race or prostate specific antigen as the criterion for high risk. We calculated the proportion of prostate cancer deaths that would occur in those men by age 75 years. Screening based on family history involved 10% of men, accounting for 14% of prostate cancer deaths. Using black race as a risk criterion involved 13% of men, accounting for 28% of deaths. In contrast, 44% of prostate cancer deaths occurred in the 10% of men with the highest prostate specific antigen at age 45 years. In no sensitivity analysis for race and family history did the ratio of risk group size to number of prostate cancer deaths in that risk group approach that of prostate specific antigen. Basing decisions for early screening on prostate specific antigen at age 45 years provided the best ratio between men screened and potential cancer deaths avoided. Given the lack of evidence that race or family history affects the relationship between prostate specific antigen and risk, prostate specific antigen based risk stratification would likely include any black men or men with a family history who are destined to experience aggressive disease. Differential screening based on risk should be informed by baseline prostate specific antigen. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Estimating preferences for treatments in patients with localized prostate cancer.
Ávila, Mónica; Becerra, Virginia; Guedea, Ferran; Suárez, José Francisco; Fernandez, Pablo; Macías, Víctor; Mariño, Alfonso; Hervás, Asunción; Herruzo, Ismael; Ortiz, María José; Ponce de León, Javier; Sancho, Gemma; Cunillera, Oriol; Pardo, Yolanda; Cots, Francesc; Ferrer, Montse
2015-02-01
Studies of patients' preferences for localized prostate cancer treatments have assessed radical prostatectomy and external radiation therapy, but none of them has evaluated brachytherapy. The aim of our study was to assess the preferences and willingness to pay of patients with localized prostate cancer who had been treated with radical prostatectomy, external radiation therapy, or brachytherapy, and their related urinary, sexual, and bowel side effects. This was an observational, prospective cohort study with follow-up until 5 years after treatment. A total of 704 patients with low or intermediate risk localized prostate cancer were consecutively recruited from 2003 to 2005. The estimation of preferences was conducted using time trade-off, standard gamble, and willingness-to-pay methods. Side effects were measured with the Expanded Prostate Index Composite (EPIC), a prostate cancer-specific questionnaire. Tobit models were constructed to assess the impact of treatment and side effects on patients' preferences. Propensity score was applied to adjust for treatment selection bias. Of the 580 patients reporting preferences, 165 were treated with radical prostatectomy, 152 with external radiation therapy, and 263 with brachytherapy. Both time trade-off and standard gamble results indicated that the preferences of patients treated with brachytherapy were 0.06 utilities higher than those treated with radical prostatectomy (P=.01). Similarly, willingness-to-pay responses showed a difference of €57/month (P=.004) between these 2 treatments. Severe urinary incontinence presented an independent impact on the preferences elicited (P<.05), whereas no significant differences were found by bowel and sexual side effects. Our findings indicate that urinary incontinence is the side effect with the highest impact on preferences and that brachytherapy and external radiation therapy are more valued than radical prostatectomy. These time trade-off and standard gamble preference assessments as well as the willingness-to-pay estimation could be useful to perform respectively cost-utility or cost-benefit analyses, which can guide health policy decisions. Copyright © 2015 Elsevier Inc. All rights reserved.
Estimating Preferences for Treatments in Patients With Localized Prostate Cancer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ávila, Mónica; CIBER en Epidemiología y Salud Pública; Universitat Pompeu Fabra, Barcelona
Purpose: Studies of patients' preferences for localized prostate cancer treatments have assessed radical prostatectomy and external radiation therapy, but none of them has evaluated brachytherapy. The aim of our study was to assess the preferences and willingness to pay of patients with localized prostate cancer who had been treated with radical prostatectomy, external radiation therapy, or brachytherapy, and their related urinary, sexual, and bowel side effects. Methods and Materials: This was an observational, prospective cohort study with follow-up until 5 years after treatment. A total of 704 patients with low or intermediate risk localized prostate cancer were consecutively recruited from 2003more » to 2005. The estimation of preferences was conducted using time trade-off, standard gamble, and willingness-to-pay methods. Side effects were measured with the Expanded Prostate Index Composite (EPIC), a prostate cancer-specific questionnaire. Tobit models were constructed to assess the impact of treatment and side effects on patients' preferences. Propensity score was applied to adjust for treatment selection bias. Results: Of the 580 patients reporting preferences, 165 were treated with radical prostatectomy, 152 with external radiation therapy, and 263 with brachytherapy. Both time trade-off and standard gamble results indicated that the preferences of patients treated with brachytherapy were 0.06 utilities higher than those treated with radical prostatectomy (P=.01). Similarly, willingness-to-pay responses showed a difference of €57/month (P=.004) between these 2 treatments. Severe urinary incontinence presented an independent impact on the preferences elicited (P<.05), whereas no significant differences were found by bowel and sexual side effects. Conclusions: Our findings indicate that urinary incontinence is the side effect with the highest impact on preferences and that brachytherapy and external radiation therapy are more valued than radical prostatectomy. These time trade-off and standard gamble preference assessments as well as the willingness-to-pay estimation could be useful to perform respectively cost-utility or cost-benefit analyses, which can guide health policy decisions.« less
Elastic registration of prostate MR images based on state estimation of dynamical systems
NASA Astrophysics Data System (ADS)
Marami, Bahram; Ghoul, Suha; Sirouspour, Shahin; Capson, David W.; Davidson, Sean R. H.; Trachtenberg, John; Fenster, Aaron
2014-03-01
Magnetic resonance imaging (MRI) is being increasingly used for image-guided biopsy and focal therapy of prostate cancer. A combined rigid and deformable registration technique is proposed to register pre-treatment diagnostic 3T magnetic resonance (MR) images, with the identified target tumor(s), to the intra-treatment 1.5T MR images. The pre-treatment 3T images are acquired with patients in strictly supine position using an endorectal coil, while 1.5T images are obtained intra-operatively just before insertion of the ablation needle with patients in the lithotomy position. An intensity-based registration routine rigidly aligns two images in which the transformation parameters is initialized using three pairs of manually selected approximate corresponding points. The rigid registration is followed by a deformable registration algorithm employing a generic dynamic linear elastic deformation model discretized by the finite element method (FEM). The model is used in a classical state estimation framework to estimate the deformation of the prostate based on a similarity metric between pre- and intra-treatment images. Registration results using 10 sets of prostate MR images showed that the proposed method can significantly improve registration accuracy in terms of target registration error (TRE) for all prostate substructures. The root mean square (RMS) TRE of 46 manually identified fiducial points was found to be 2.40+/-1.20 mm, 2.51+/-1.20 mm, and 2.28+/-1.22mm for the whole gland (WG), central gland (CG), and peripheral zone (PZ), respectively after deformable registration. These values are improved from 3.15+/-1.60 mm, 3.09+/-1.50 mm, and 3.20+/-1.73mm in the WG, CG and PZ, respectively resulted from rigid registration. Registration results are also evaluated based on the Dice similarity coefficient (DSC), mean absolute surface distances (MAD) and maximum absolute surface distances (MAXD) of the WG and CG in the prostate images.
Estimation of a Nonlinear Intervention Phase Trajectory for Multiple-Baseline Design Data
ERIC Educational Resources Information Center
Hembry, Ian; Bunuan, Rommel; Beretvas, S. Natasha; Ferron, John M.; Van den Noortgate, Wim
2015-01-01
A multilevel logistic model for estimating a nonlinear trajectory in a multiple-baseline design is introduced. The model is applied to data from a real multiple-baseline design study to demonstrate interpretation of relevant parameters. A simple change-in-levels (?"Levels") model and a model involving a quadratic function…
Benchmarking Foot Trajectory Estimation Methods for Mobile Gait Analysis
Ollenschläger, Malte; Roth, Nils; Klucken, Jochen
2017-01-01
Mobile gait analysis systems based on inertial sensing on the shoe are applied in a wide range of applications. Especially for medical applications, they can give new insights into motor impairment in, e.g., neurodegenerative disease and help objectify patient assessment. One key component in these systems is the reconstruction of the foot trajectories from inertial data. In literature, various methods for this task have been proposed. However, performance is evaluated on a variety of datasets due to the lack of large, generally accepted benchmark datasets. This hinders a fair comparison of methods. In this work, we implement three orientation estimation and three double integration schemes for use in a foot trajectory estimation pipeline. All methods are drawn from literature and evaluated against a marker-based motion capture reference. We provide a fair comparison on the same dataset consisting of 735 strides from 16 healthy subjects. As a result, the implemented methods are ranked and we identify the most suitable processing pipeline for foot trajectory estimation in the context of mobile gait analysis. PMID:28832511
Choo, Richard; Klotz, Laurence; Deboer, Gerrit; Danjoux, Cyril; Morton, Gerard C
2004-08-01
To assess the prostate specific antigen (PSA) doubling time of untreated, clinically localized, low-to-intermediate grade prostate carcinoma. A prospective single-arm cohort study has been in progress since November 1995 to assess the feasibility of a watchful-observation protocol with selective delayed intervention for clinically localized, low-to-intermediate grade prostate adenocarcinoma. The PSA doubling time was estimated from a linear regression of ln(PSA) against time, assuming a simple exponential growth model. As of March 2003, 231 patients had at least 6 months of follow-up (median 45) and at least three PSA measurements (median 8, range 3-21). The distribution of the doubling time was: < 2 years, 26 patients; 2-5 years, 65; 5-10 years, 42; 10-20 years, 26; 20-50 years, 16; >50 years, 56. The median doubling time was 7.0 years; 42% of men had a doubling time of >10 years. The doubling time of untreated clinically localized, low-to-intermediate grade prostate cancer varies widely.
A Survey of Methods for Computing Best Estimates of Endoatmospheric and Exoatmospheric Trajectories
NASA Technical Reports Server (NTRS)
Bernard, William P.
2018-01-01
Beginning with the mathematical prediction of planetary orbits in the early seventeenth century up through the most recent developments in sensor fusion methods, many techniques have emerged that can be employed on the problem of endo and exoatmospheric trajectory estimation. Although early methods were ad hoc, the twentieth century saw the emergence of many systematic approaches to estimation theory that produced a wealth of useful techniques. The broad genesis of estimation theory has resulted in an equally broad array of mathematical principles, methods and vocabulary. Among the fundamental ideas and methods that are briefly touched on are batch and sequential processing, smoothing, estimation, and prediction, sensor fusion, sensor fusion architectures, data association, Bayesian and non Bayesian filtering, the family of Kalman filters, models of the dynamics of the phases of a rocket's flight, and asynchronous, delayed, and asequent data. Along the way, a few trajectory estimation issues are addressed and much of the vocabulary is defined.
Trajectories of Parenting Processes and Adolescent Substance Use: Reciprocal Effects
ERIC Educational Resources Information Center
Coley, Rebekah Levine; Votruba-Drzal, Elizabeth; Schindler, Holly S.
2008-01-01
Drawing on transactional theories of child development, we assessed bidirectional links between trajectories of adolescent substance use and parenting processes from early through mid adolescence. Hierarchical generalized models estimated trajectories for 3,317 adolescents from the National Longitudinal Survey of Youth 1997, exploring both…
NASA Astrophysics Data System (ADS)
Chen, Wo-Hsing; Sanghvi, Narendra T.; Carlson, Roy; Schatzl, Georg; Marberger, Michael
2012-10-01
The Sonablate® 500 has quantitative, real-time Tissue Change Monitoring (TCM) software that estimates changes in tissue properties due to HIFU treatment of prostate cancer. This study validates the Sonablate 500 TCM system using real-time thermometry. Five patients with histologically confirmed, organ-confined prostate cancer were enrolled. Four patients with focal cancer had hemiablation and one had whole gland ablation. TCM generates energy reading based on spectral analysis on the RF backscattered ultrasound signals; results are used as an estimator of tissue temperature. Needle thermocouples were placed transperineally under TRUS guidance in the prostate to monitor temperatures from focal zone, posterior to the focal zone and on the lateral gland where no HIFU was applied. The HIFU treatments averaged 37, 35 and 19.7 Watts for the treatment for anterior, middle and posterior zones. The measured temperatures (Average, Max, and Min) in the HIFU treatment zones were 84, 114 and 70 degrees C. The temperature estimated by TCM energy readings were 83% 75-100 degrees C and 17% 60-75 degrees C with an average of 91 degrees C. Outside the focal zone, average recorded temperature was 50 degrees C. Average temperature in the lateral lobe where no HIFU was applied was 40.7 degrees C.
NASA Technical Reports Server (NTRS)
Idris, Husni; Vivona, Robert A.; Al-Wakil, Tarek
2009-01-01
This document describes exploratory research on a distributed, trajectory oriented approach for traffic complexity management. The approach is to manage traffic complexity based on preserving trajectory flexibility and minimizing constraints. In particular, the document presents metrics for trajectory flexibility; a method for estimating these metrics based on discrete time and degree of freedom assumptions; a planning algorithm using these metrics to preserve flexibility; and preliminary experiments testing the impact of preserving trajectory flexibility on traffic complexity. The document also describes an early demonstration capability of the trajectory flexibility preservation function in the NASA Autonomous Operations Planner (AOP) platform.
NASA Astrophysics Data System (ADS)
Li, Chunhui; Guan, Guangying; Ling, Yuting; Lang, Stephen; Wang, Ruikang K.; Huang, Zhihong; Nabi, Ghulam
2015-03-01
Objectives. Prostate cancer is the most frequently diagnosed malignancy in men. Digital rectal examination (DRE) - a known clinical tool based on alteration in the mechanical properties of tissues due to cancer has traditionally been used for screening prostate cancer. Essentially, DRE estimates relative stiffness of cancerous and normal prostate tissue. Optical coherence elastography (OCE) are new optical imaging techniques capable of providing cross-sectional imaging of tissue microstructure as well as elastogram in vivo and in real time. In this preliminary study, OCE was used in the setting of the human prostate biopsies ex vivo, and the images acquired were compared with those obtained using standard histopathologic methods. Methods. 120 prostate biopsies were obtained by TRUS guided needle biopsy procedures from 9 patients with clinically suspected cancer of the prostate. The biopsies were approximately 0.8mm in diameter and 12mm in length, and prepared in Formalin solution. Quantitative assessment of biopsy samples using OCE was obtained in kilopascals (kPa) before histopathologic evaluation. The results obtained from OCE and standard histopathologic evaluation were compared provided the cross-validation. Sensitivity, specificity, and positive and negative predictive values were calculated for OCE (histopathology was a reference standard). Results. OCE could provide quantitative elasticity properties of prostate biopsies within benign prostate tissue, prostatic intraepithelial neoplasia, atypical hyperplasia and malignant prostate cancer. Data analysed showed that the sensitivity and specificity of OCE for PCa detection were 1 and 0.91, respectively. PCa had significantly higher stiffness values compared to benign tissues, with a trend of increasing in stiffness with increasing of malignancy. Conclusions. Using OCE, microscopic resolution elastogram is promising in diagnosis of human prostatic diseases. Further studies using this technique to improve the detection and staging of malignant cancer of the prostate are ongoing.
Reading, Stephanie R; Porter, Kimberly R; Hsu, Jin-Wen Y; Wallner, Lauren P; Loo, Ronald K; Jacobsen, Steven J
2016-10-01
To examine the racial and ethnic variation in time to prostate biopsy after an elevated screening level of serum prostate-specific antigen (PSA). Male members of the Kaiser Permanente of Southern California health plan, 45 years of age or older, with no history of prostate cancer or a prostate biopsy, and at least 1 elevated screening level of serum PSA between January 1, 1998 and December 31, 2007 were retrospectively identified (n = 59,506). All participants were passively followed via electronic health records until their time of prostate biopsy, death, membership disenrollment, or study conclusion (December 31, 2014), whichever was the initial event. Proportional hazard regression analyses were used to estimate the association between time from an elevated screening level of serum PSA to prostate biopsy, adjusting for age, benign prostatic hyperplasia, prostatitis, type 2 diabetes mellitus, hypertension, and Charlson Comorbidity Index score. Median time until biopsy was 0.6 years (214 days), with approximately 41% of participants receiving a prostate biopsy within the study period. Results from the fully adjusted analysis indicated that the non-Hispanic Asian or Pacific Islanders (hazard ratio: 1.10, 95% confidence interval: [1.04, 1.15]) and the non-Hispanic blacks (hazard ratio: 1.04, 95% confidence interval: [1.00, 1.08]) had a slightly shorter time to prostate biopsy after an elevated screening level of serum PSA compared to the non-Hispanic whites. These data suggest that, within an integrated healthcare organization, minimal differences exist between racial and ethnic subgroups in their time to prostate biopsy after an elevated screening level of serum PSA. Copyright © 2016. Published by Elsevier Inc.
Andren, Ove; Ohlson, Anna‐Lena; Carlsson, Jessica; Andersson, Swen‐Olof; Giunchi, Francesca; Rider, Jennifer R.; Fiorentino, Michelangelo
2017-01-01
Background The tumor promoting or counteracting effects of the immune response to cancer development are thought to be mediated to some extent by the infiltration of regulatory T cells (Tregs). In the present study we evaluated the prevalence of Treg populations in stromal and epithelial compartments of normal, post atrophic hyperplasia (PAH), prostatic intraepithelial neoplasia (PIN), and tumor lesions in men with and without prostate cancer. Methods Study subjects were 102 men consecutively diagnosed with localized prostate cancer undergoing radical prostatectomy and 38 men diagnosed with bladder cancer undergoing cystoprostatectomy without prostate cancer at the pathological examination. Whole mount sections from all patients were evaluated for the epithelial and stromal expression of CD4+ Tregs and CD8+ Tregs in normal, PAH, PIN, and tumor lesions. A Friedmańs test was used to investigate differences in the mean number of Tregs across histological lesions. Logistic regression was used to estimate crude and adjusted odds ratios (OR) for prostate cancer for each histological area. Results In men with prostate cancer, similarly high numbers of stromal CD4+ Tregs were identified in PAH and tumor, but CD4+ Tregs were less common in PIN. Greater numbers of epithelial CD4+ Tregs in normal prostatic tissue were positively associated with both Gleason score and pT‐stage. We observed a fourfold increased risk of prostate cancer in men with epithelial CD4+ Tregs in the normal prostatic tissue counterpart. Conclusions Our results may suggest a possible pathway through which PAH develops directly into prostate cancer in the presence of CD4+ Tregs and indicate that transformation of the anti‐tumor immune response may be initiated even before the primary tumor is established. PMID:29105795
Distinct Trajectories in the Transition to Adulthood: Are Children of Immigrants Advantaged?
ERIC Educational Resources Information Center
Hao, Lingxin; Woo, Han S.
2012-01-01
Studies on children of immigrants have generally ignored distinct developmental trajectories during adolescence and their role in the transition to adulthood. This study identifies distinct trajectories in cognitive, sociobehavioral, and psychological domains and estimates their consequences for young adults. Drawing data from a nationally…
Skorpil, M; Brynolfsson, P; Engström, M
2017-06-01
Multiparametric magnetic resonance imaging (MRI) and PI-RADS (Prostate Imaging - Reporting and Data System) has become the standard to determine a probability score for a lesion being a clinically significant prostate cancer. T2-weighted and diffusion-weighted imaging (DWI) are essential in PI-RADS, depending partly on visual assessment of signal intensity, while dynamic-contrast enhanced imaging is less important. To decrease inter-rater variability and further standardize image evaluation, complementary objective measures are in need. We here demonstrate a sequence enabling simultaneous quantification of apparent diffusion coefficient (ADC) and T2-relaxation, as well as calculation of the perfusion fraction f from low b-value intravoxel incoherent motion data. Expandable wait pulses were added to a FOCUS DW SE-EPI sequence, allowing the effective echo time to change at run time. To calculate both ADC and f, b-values 200s/mm 2 and 600s/mm 2 were chosen, and for T2-estimation 6 echo times between 64.9ms and 114.9ms were used. Three patients with prostate cancer were examined and all had significantly decreased ADC and T2-values, while f was significantly increased in 2 of 3 tumors. T2 maps obtained in phantom measurements and in a healthy volunteer were compared to T2 maps from a SE sequence with consecutive scans, showing good agreement. In addition, a motion correction procedure was implemented to reduce the effects of prostate motion, which improved T2-estimation. This sequence could potentially enable more objective tumor grading, and decrease the inter-rater variability in the PI-RADS classification. Copyright © 2017 Elsevier Inc. All rights reserved.
Perlroth, Daniella J; Bhattacharya, Jay; Goldman, Dana P; Garber, Alan M
2012-12-01
Comparative effectiveness research suggests that conservative management (CM) strategies are no less effective than active initial treatment for many men with localized prostate cancer. We estimate longer-term costs of initial management strategies and potential US health expenditure savings by increased use of conservative management for men with localized prostate cancer. Five-year total health expenditures attributed to initial management strategies for localized prostate cancer were calculated using commercial claims data from 1998 to 2006, and savings were estimated from a US population health-care expenditure model. Our analysis finds that patients receiving combinations of active treatments have the highest additional costs over conservative management at $63 500, followed by $48 550 for intensity-modulated radiation therapy, $37 500 for primary androgen deprivation therapy, and $28 600 for brachytherapy. Radical prostatectomy ($15 200) and external beam radiation therapy ($18 900) were associated with the lowest costs. The population model estimated that US health expenditures could be lowered by 1) use of initial CM over all active treatment ($2.9-3.25 billion annual savings), 2) shifting patients receiving intensity-modulated radiation therapy to CM ($680-930 million), 3) foregoing primary androgen deprivation therapy($555 million), 4) reducing the use of adjuvant androgen deprivation in addition to local therapies ($630 million), and 5) using single treatments rather than combination local treatment ($620-655 million). In conclusion, we find that all active treatments are associated with higher longer-term costs than CM. Substantial savings, representing up to 30% of total costs, could be realized by adopting CM strategies, including active surveillance, for initial management of men with localized prostate cancer.
Danylov, Iu V; Motkov, K V; Shevchenko, T I
2014-01-01
The morphometric estimation of parenchyma and stroma condition included the determination of 25 parameters in a prostate gland at 27 persons. The mathematical model of morphogenesis of prostate gland was created by Bayes' method. The method of differential diagnosis of a prostate gland tissues' changes conditioned by the influence of the Chernobyl factor and/or unfavorable terms of the work in underground coal mines have been worked out. Its practical use provides exactness and reliability of the diagnosis (not less than 95%), independence from the level of the qualification and personal experience of the doctor, allows us to unify, optimize and individualize the diagnostic algorithms, answer the requirements of evidential medicine.
Prostate Cancer Stem-Like Cells | Center for Cancer Research
Prostate cancer is the third leading cause of cancer-related death among men, killing an estimated 27,000 men each year in the United States. Men with advanced prostate cancer often become resistant to conventional therapies. Many researchers speculate that the emergence of resistance is due to the presence of cancer stem cells, which are believed to be a small subpopulation of tumor cells that can self-renew and give rise to more differentiated tumor cells. It is thought that these stem cells survive initial therapies (such as chemotherapy and hormone therapy) and then generate new tumor cells that are resistant to these standard treatments. If prostate cancer stem cells could be identified and characterized, it might be possible to design treatments that prevent resistance.
Horizontal mixing in the Southern Ocean from Argo float trajectories
NASA Astrophysics Data System (ADS)
Roach, Christopher J.; Balwada, Dhruv; Speer, Kevin
2016-08-01
We provide the first observational estimate of the circumpolar distribution of cross-stream eddy diffusivity at 1000 m in the Southern Ocean using Argo float trajectories. We show that Argo float trajectories, from the float surfacing positions, can be used to estimate lateral eddy diffusivities in the ocean and that these estimates are comparable to those obtained from RAFOS floats, where they overlap. Using the Southern Ocean State Estimate (SOSE) velocity fields to advect synthetic particles with imposed behavior that is "Argo-like" and "RAFOS-like" diffusivity estimates from both sets of synthetic particles agreed closely at the three dynamically very different test sites, the Kerguelen Island region, the Southeast Pacific Ocean, and the Scotia Sea, and support our approach. Observed cross-stream diffusivities at 1000 m, calculated from Argo float trajectories, ranged between 300 and 2500 m2 s-1, with peaks corresponding to topographic features associated with the Scotia Sea, the Kerguelen Plateau, the Campbell Plateau, and the Southeast Pacific Ridge. These observational estimates agree with previous regional estimates from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) near the Drake Passage, and other estimates from natural tracers (helium), inverse modeling studies, and current meter measurements. These estimates are also compared to the suppressed eddy diffusivity in the presence of mean flows. The comparison suggests that away from regions of strong topographic steering suppression explains both the structure and magnitude of eddy diffusivity but that eddy diffusivities in the regions of topographic steering are greater than what would be theoretically expected and the ACC experiences localized enhanced cross-stream mixing in these regions.
U.S. dietary exposures to heterocyclic amines.
Bogen, K T; Keating, G A
2001-01-01
Heterocyclic amines (HAs) formed in fried, broiled or grilled meats are potent mutagens that increase rates of colon, mammary, prostate and other cancers in bioassay rodents. Studies of how human dietary HA exposures may affect cancer risks have so far relied on fairly crudely defined HA-exposure categories. Recently, an integrated, quantitative approach to HA-exposure assessment (HAEA) was developed to estimate compound-specific intakes for particular individuals based on corresponding HA-concentration estimates that reflect their meat-type, intake-rate, cooking-method and meat-doneness preferences. This method was applied in the present study to U.S. national Continuing Survey of Food Intakes by Individuals (CSFII) data on meats consumed and cooking methods used by >25,000 people, after adjusting for underreported energy intake and conditional on meat-doneness preferences estimated from additional survey data. The U.S. population average lifetime time-weighted average of total HAs consumed was estimated to be approximately 9 ng/kg/day, with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) estimated to comprise about two thirds of this intake. Pan-fried meats were the largest source of HA in the diet and chicken the largest source of HAs among different meat types. Estimated total HA intakes by male vs. female children were generally similar, with those by (0- to 15-year-old) children approximately 25% greater than those by (16+-year-old) adults. Race-, age- and sex-specific mean HA intakes were estimated to be greatest for African American males, who were estimated to consume approximately 2- and approximately 3-fold more PhIP than white males at ages <16 and 30+ years, respectively, after considering a relatively greater preference for more well-done items among African Americans based on national survey data. This difference in PhIP intakes may at least partly explain why prostate cancer (PC) kills approximately 2-fold more African American than white men, in view of experimental data indicating that PhIP mutates prostate DNA and causes prostate tumors in rats.
Pataky, Reka; Gulati, Roman; Etzioni, Ruth; Black, Peter; Chi, Kim N.; Coldman, Andrew J.; Pickles, Tom; Tyldesley, Scott; Peacock, Stuart
2015-01-01
Prostate-specific antigen (PSA) screening for prostate cancer may reduce mortality, but it incurs considerable risk of overdiagnosis and potential harm to quality of life. Our objective was to evaluate the cost-effectiveness of PSA screening, with and without adjustment for quality of life, for the British Columbia (BC) population. We adapted an existing natural history model using BC incidence, treatment, cost and mortality patterns. The modeled mortality benefit of screening derives from a stage-shift mechanism, assuming mortality reduction consistent with the European Study of Randomized Screening for Prostate Cancer. The model projected outcomes for 40 year-old men under 14 combinations of screening ages and frequencies. Cost and utility estimates were explored with deterministic sensitivity analysis. The incremental cost-effectiveness of regular screening ranged from $36,300/LYG, for screening every four years from ages 55-69, to $588,300/LYG, for screening every two years from ages 40-74. The marginal benefits of increasing screening frequency to two years or starting screening at age 40 were small and came at significant cost. After utility adjustment, all screening strategies resulted in a loss of QALYs; however, this result was very sensitive to utility estimates. Plausible outcomes under a range of screening strategies inform discussion of prostate cancer screening policy in BC and similar jurisdictions. Screening may be cost-effective but the sensitivity of results to utility values suggests individual preferences for quality versus quantity of life should be a key consideration. PMID:24443367
Bolch, Charlotte A; Chu, Haitao; Jarosek, Stephanie; Cole, Stephen R; Elliott, Sean; Virnig, Beth
2017-07-10
To illustrate the 10-year risks of urinary adverse events (UAEs) among men diagnosed with prostate cancer and treated with different types of therapy, accounting for the competing risk of death. Prostate cancer is the second most common malignancy among adult males in the United States. Few studies have reported the long-term post-treatment risk of UAEs and those that have, have not appropriately accounted for competing deaths. This paper conducts an inverse probability of treatment (IPT) weighted competing risks analysis to estimate the effects of different prostate cancer treatments on the risk of UAE, using a matched-cohort of prostate cancer/non-cancer control patients from the Surveillance, Epidemiology and End Results (SEER) Medicare database. Study dataset included men age 66 years or older that are 83% white and had a median follow-up time of 4.14 years. Patients that underwent combination radical prostatectomy and external beam radiotherapy experienced the highest risk of UAE (IPT-weighted competing risks: HR 3.65 with 95% CI (3.28, 4.07); 10-yr. cumulative incidence = 36.5%). Findings suggest that IPT-weighted competing risks analysis provides an accurate estimator of the cumulative incidence of UAE taking into account the competing deaths as well as measured confounding bias.
NASA Astrophysics Data System (ADS)
Galanti, Eli; Durante, Daniele; Iess, Luciano; Kaspi, Yohai
2017-04-01
The ongoing Juno spacecraft measurements are improving our knowledge of Jupiter's gravity field. Similarly, the Cassini Grand Finale will improve the gravity estimate of Saturn. The analysis of the Juno and Cassini Doppler data will provide a very accurate reconstruction of spacial gravity variations, but these measurements will be very accurate only over a limited latitudinal range. In order to deduce the full gravity fields of Jupiter and Saturn, additional information needs to be incorporated into the analysis, especially with regards to the planets' wind structures. In this work we propose a new iterative approach for the estimation of Jupiter and Saturn gravity fields, using simulated measurements, a trajectory estimation model, and an adjoint based inverse thermal wind model. Beginning with an artificial gravitational field, the trajectory estimation model is used to obtain the gravitational moments. The solution from the trajectory model is then used as an initial guess for the thermal wind model, and together with an optimization method, the likely penetration depth of the winds is computed, and its uncertainty is evaluated. As a final step, the gravity harmonics solution from the thermal wind model is given back to the trajectory model, along with an estimate of their uncertainties, to be used as a priori for a new calculation of the gravity field. We test this method both for zonal harmonics only and with a full gravity field including tesseral harmonics. The results show that by using this method some of the gravitational moments are fitted better to the `observed' ones, mainly due to the added information from the dynamical model which includes the wind structure and its depth. Thus, it is suggested that the method presented here has the potential of improving the accuracy of the expected gravity moments estimated from the Juno and Cassini radio science experiments.
Maximum likelihood-based analysis of single-molecule photon arrival trajectories
NASA Astrophysics Data System (ADS)
Hajdziona, Marta; Molski, Andrzej
2011-02-01
In this work we explore the statistical properties of the maximum likelihood-based analysis of one-color photon arrival trajectories. This approach does not involve binning and, therefore, all of the information contained in an observed photon strajectory is used. We study the accuracy and precision of parameter estimates and the efficiency of the Akaike information criterion and the Bayesian information criterion (BIC) in selecting the true kinetic model. We focus on the low excitation regime where photon trajectories can be modeled as realizations of Markov modulated Poisson processes. The number of observed photons is the key parameter in determining model selection and parameter estimation. For example, the BIC can select the true three-state model from competing two-, three-, and four-state kinetic models even for relatively short trajectories made up of 2 × 103 photons. When the intensity levels are well-separated and 104 photons are observed, the two-state model parameters can be estimated with about 10% precision and those for a three-state model with about 20% precision.
Annualized TASAR Benefit Estimate for Alaska Airlines Operations
NASA Technical Reports Server (NTRS)
Henderson, Jeffrey
2015-01-01
The Traffic Aware Strategic Aircrew Request (TASAR) concept offers onboard automation for the purpose of advising the pilot of traffic compatible trajectory changes that would be beneficial to the flight. A fast-time simulation study was conducted to assess the benefits of TASAR to Alaska Airlines. The simulation compares historical trajectories without TASAR to trajectories developed with TASAR and evaluated by controllers against their objectives. It was estimated that between 8,000 and 12,000 gallons of fuel and 900 to 1,300 minutes could be saved annually per aircraft. These savings were applied fleet-wide to produce an estimated annual cost savings to Alaska Airlines in excess of $5 million due to fuel, maintenance, and depreciation cost savings. Switching to a more wind-optimal trajectory was found to be the use case that generated the highest benefits out of the three TASAR use cases analyzed. Alaska TASAR requests peaked at four to eight requests per hour in high-altitude Seattle center sectors south of Seattle-Tacoma airport.
Annualized TASAR Benefit Estimate for Virgin America Operations
NASA Technical Reports Server (NTRS)
Henderson, Jeffrey
2015-01-01
The Traffic Aware Strategic Aircrew Request (TASAR) concept offers onboard automation for the purpose of advising the pilot of traffic compatible trajectory changes that would be beneficial to the flight. A fast-time simulation study was conducted to assess the benefits of TASAR to Virgin America. The simulation compares historical trajectories without TASAR to trajectories developed with TASAR and evaluated by controllers against their objectives. It was estimated that about 25,000 gallons of fuel and about 2,500 minutes could be saved annually per aircraft. These savings were applied fleet-wide to produce an estimated annual cost savings to Virgin America in excess of $5 million due to fuel, maintenance, and depreciation cost savings. Switching to a more wind-optimal trajectory was found to be the use case that generated the highest benefits out of the three TASAR use cases analyzed. Virgin America TASAR requests peaked at two to four requests per hour per sector in high-altitude Oakland and Salt Lake City center sectors east of San Francisco.
Unemployment and prostate cancer mortality in the OECD, 1990–2009
Maruthappu, Mahiben; Watkins, Johnathan; Taylor, Abigail; Williams, Callum; Ali, Raghib; Zeltner, Thomas; Atun, Rifat
2015-01-01
The global economic downturn has been associated with increased unemployment in many countries. Insights into the impact of unemployment on specific health conditions remain limited. We determined the association between unemployment and prostate cancer mortality in members of the Organisation for Economic Co-operation and Development (OECD). We used multivariate regression analysis to assess the association between changes in unemployment and prostate cancer mortality in OECD member states between 1990 and 2009. Country-specific differences in healthcare infrastructure, population structure, and population size were controlled for and lag analyses conducted. Several robustness checks were also performed. Time trend analyses were used to predict the number of excess deaths from prostate cancer following the 2008 global recession. Between 1990 and 2009, a 1% rise in unemployment was associated with an increase in prostate cancer mortality. Lag analysis showed a continued increase in mortality years after unemployment rises. The association between unemployment and prostate cancer mortality remained significant in robustness checks with 46 controls. Eight of the 21 OECD countries for which a time trend analysis was conducted, exhibited an estimated excess of prostate cancer deaths in at least one of 2008, 2009, or 2010, based on 2000–2007 trends. Rises in unemployment are associated with significant increases in prostate cancer mortality. Initiatives that bolster employment may help to minimise prostate cancer mortality during times of economic hardship. PMID:26045715
Unemployment and prostate cancer mortality in the OECD, 1990-2009.
Maruthappu, Mahiben; Watkins, Johnathan; Taylor, Abigail; Williams, Callum; Ali, Raghib; Zeltner, Thomas; Atun, Rifat
2015-01-01
The global economic downturn has been associated with increased unemployment in many countries. Insights into the impact of unemployment on specific health conditions remain limited. We determined the association between unemployment and prostate cancer mortality in members of the Organisation for Economic Co-operation and Development (OECD). We used multivariate regression analysis to assess the association between changes in unemployment and prostate cancer mortality in OECD member states between 1990 and 2009. Country-specific differences in healthcare infrastructure, population structure, and population size were controlled for and lag analyses conducted. Several robustness checks were also performed. Time trend analyses were used to predict the number of excess deaths from prostate cancer following the 2008 global recession. Between 1990 and 2009, a 1% rise in unemployment was associated with an increase in prostate cancer mortality. Lag analysis showed a continued increase in mortality years after unemployment rises. The association between unemployment and prostate cancer mortality remained significant in robustness checks with 46 controls. Eight of the 21 OECD countries for which a time trend analysis was conducted, exhibited an estimated excess of prostate cancer deaths in at least one of 2008, 2009, or 2010, based on 2000-2007 trends. Rises in unemployment are associated with significant increases in prostate cancer mortality. Initiatives that bolster employment may help to minimise prostate cancer mortality during times of economic hardship.
de Vogel, Stefan; Ulvik, Arve; Meyer, Klaus; Ueland, Per Magne; Nygård, Ottar; Vollset, Stein Emil; Tell, Grethe S; Gregory, Jesse F; Tretli, Steinar; Bjørge, Tone
2014-01-01
Methyl group donors and intermediates of one-carbon metabolism affect DNA synthesis and DNA methylation, and may thereby affect prostate carcinogenesis. Choline, the precursor of betaine, and the one-carbon metabolite sarcosine have been associated with increased prostate cancer risk. Within JANUS, a prospective cohort in Norway (n = 317,000) with baseline serum samples, we conducted a nested case-control study among 3,000 prostate cancer cases and 3,000 controls. Using conditional logistic regression, odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer risk were estimated according to quintiles of circulating betaine, dimethylglycine (DMG), sarcosine, glycine and serine. High sarcosine and glycine concentrations were associated with reduced prostate cancer risk of borderline significance (sarcosine: highest vs. lowest quintile OR = 0.86, CI = 0.72-1.01, p(trend) = 0.03; glycine: OR = 0.83, CI = 0.70-1.00, p(trend) = 0.07). Serum betaine, DMG and serine were not associated with prostate cancer risk. However, individuals with a high glycine/serine ratio were at decreased prostate cancer risk (OR = 0.74, CI = 0.69-0.85, p(trend) < 0.001). This population-based study suggested that men with high serum sarcosine or glycine concentrations have modestly reduced prostate cancer risk. Ratios of metabolites reflecting one-carbon balance may be associated with prostate cancer risk, as demonstrated for the glycine/serine ratio, and should be explored in future studies. © 2013 UICC.
Sreenivasulu, Karli; Nandeesha, Hanumanthappa; Dorairajan, Lalgudi Narayanan; Rajappa, Medha; Vinayagam, Vickneshwaran
2017-06-01
Insulin and insulin like growth factor-1 (IGF-1) have growth promoting effects, while insulin like growth factor binding protein-3 (IGFBP-3) has growth inhibitory effects. The present study was designed to assess the concentrations of insulin, IGF-1, IGFBP-3 and their association with prostate size in patients with BPH. Ninety 90 BPH cases and 90 controls were enrolled in the study. Insulin, IGF-1, IGFBP-3, PSA, testosterone and estradiol were estimated in both the groups. Insulin, IGF-1 and estradiol were increased and IGFBP-3/PSA was decreased in BPH cases when compared with controls. Insulin (r=0.64, p=0.001) and IGF-1 (r=0.22, p=0.03) were positively correlated and IGFBP-3/PSA (r=-0.316, p=0.002) were negatively correlated with prostate size in BPH. Multivariate analysis showed that insulin (p=0.001) and IGFBP-3/PSA (p=0.004) predicts the prostate size in patients with BPH. Insulin was increased and IGFBP-3/PSA was reduced in BPH patients with increased prostate size. At a cutoff concentration of 527.52, IGFBP-3/PSA ratio was found to differentiate benign growth of prostate from normal prostate with 96% sensitivity and 96% specificity. Insulin is elevated and IGFBP-3/PSA is reduced with increase prostate size in BPH cases. Copyright © 2017 Elsevier B.V. All rights reserved.
Liu, Hai-Ying; Skjetne, Erik; Kobernus, Mike
2013-11-04
We propose a new approach to assess the impact of traffic-related air pollution on public health by mapping personal trajectories using mobile phone tracking technology in an urban environment. Although this approach is not based on any empirical studies, we believe that this method has great potential and deserves serious attention. Mobile phone tracking technology makes it feasible to generate millions of personal trajectories and thereby cover a large fraction of an urban population. Through analysis, personal trajectories are not only associated to persons, but it can also be associated with vehicles, vehicle type, vehicle speed, vehicle emission rates, and sources of vehicle emissions. Pollution levels can be estimated by dispersion models from calculated traffic emissions. Traffic pollution exposure to individuals can be estimated based on the exposure along the individual human trajectories in the estimated pollution concentration fields by utilizing modelling tools. By data integration, one may identify trajectory patterns of particularly exposed human groups. The approach of personal trajectories may open a new paradigm in understanding urban dynamics and new perspectives in population-wide empirical public health research. This new approach can be further applied to individual commuter route planning, land use planning, urban traffic network planning, and used by authorities to formulate air pollution mitigation policies and regulations.
2013-01-01
We propose a new approach to assess the impact of traffic-related air pollution on public health by mapping personal trajectories using mobile phone tracking technology in an urban environment. Although this approach is not based on any empirical studies, we believe that this method has great potential and deserves serious attention. Mobile phone tracking technology makes it feasible to generate millions of personal trajectories and thereby cover a large fraction of an urban population. Through analysis, personal trajectories are not only associated to persons, but it can also be associated with vehicles, vehicle type, vehicle speed, vehicle emission rates, and sources of vehicle emissions. Pollution levels can be estimated by dispersion models from calculated traffic emissions. Traffic pollution exposure to individuals can be estimated based on the exposure along the individual human trajectories in the estimated pollution concentration fields by utilizing modelling tools. By data integration, one may identify trajectory patterns of particularly exposed human groups. The approach of personal trajectories may open a new paradigm in understanding urban dynamics and new perspectives in population-wide empirical public health research. This new approach can be further applied to individual commuter route planning, land use planning, urban traffic network planning, and used by authorities to formulate air pollution mitigation policies and regulations. PMID:24188173
Takada, Junya; Honda, Norihiro; Hazama, Hisanao; Ioritani, Naomasa
2016-01-01
Background and Aims: Laser vaporization of the prostate is expected as a less invasive treatment for benign prostatic hyperplasia (BPH), via the photothermal effect. In order to develop safer and more effective laser vaporization of the prostate, it is essential to set optimal irradiation parameters based on quantitative evaluation of temperature distribution and thermally denatured depth in prostate tissue. Method: A simulation model was therefore devised with light propagation and heat transfer calculation, and the vaporized and thermally denatured depths were estimated by the simulation model. Results: The results of the simulation were compared with those of an ex vivo experiment and clinical trial. Based on the accumulated data, the vaporized depth strongly depended on the distance between the optical fiber and the prostate tissue, and it was suggested that contact laser irradiation could vaporize the prostate tissue most effectively. Additionally, it was suggested by analyzing thermally denatured depth comprehensively that laser irradiation at the distance of 3 mm between the optical fiber and the prostate tissue was useful for hemostasis. Conclusions: This study enabled quantitative and reproducible analysis of laser vaporization for BPH and will play a role in clarification of the safety and efficacy of this treatment. PMID:28765672
Acupuncture for chronic prostatitis: A systematic review and meta-analysis protocol.
Peng, Tianzhong; Cheng, Ying; Jin, Yuhao; Xu, Na; Guo, Taipin
2018-04-01
Chronic prostatitis (CP) is a prevalent genitourinary condition. Considering its safety profile, acupuncture can be an option treating CP symptoms. The aim of this review is to undertake a systematic review to estimate the effectiveness and safety of acupuncture on CP. We will search all randomized controlled trials for CP in August 2018 in the databases of MEDLINE, Cochrane Library, Web of Science, EMBASE, Springer, WHO International Clinical Trials Registry Platform (ICTRP), China National Knowledge Infrastructure (CNKI), Wan fang, Chinese Biomedical Literature Database (CBM), PsycInfo, Chinese Scientific Journal Database (VIP), and other available resources. Languages are limited as English and Chinese. Search terms used are will "acupuncture," and "chronic prostatitis," "non-bacterial prostatitis," "abacterial prostatitis." And duplicates will be screened. The primary outcomes consisted of improvement rate and pain relief evaluated by The National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) index. Secondary outcomes include the recurrence rate and side effects, such as pneumothorax, discomforts, and infection. This study will demonstrate an evidence-based review of acupuncture for chronic prostatitis. The study will provide clear evidence to assess the effectiveness and side effects of acupuncture for chronic prostatitis. There is no requirement of ethical approval and it will be in print or disseminated by electronic copies. CRD42018088834.
Nandeesha, H; Eldhose, A; Dorairajan, L N; Anandhi, B
2017-09-01
Elevated iron, high-sensitivity C-reactive protein (CRP) and hypoadiponectinemia are known to initiate tumour development. There is paucity of data regarding the above-mentioned parameters and their relation with prostate size in benign prostatic hyperplasia (BPH). The present study was designed to assess the levels of iron, hs-CRP and adiponectin levels and their association with prostate size in BPH patients. A total of 37 BPH cases and 36 controls were enrolled in the study. Iron, hs-CRP and adiponectin were estimated in both the groups. Iron and hs-CRP were significantly increased and adiponectin was significantly reduced in BPH cases when compared with controls. Iron (r = .397, p = .015), hs-CRP (r = .341, p = .039) and adiponectin (r = -.464, p = .004) were significantly associated with prostate size in BPH cases. Multivariate linear regression analysis showed that iron acts as predictor of prostate size in BPH (R 2 = 0.395, β = 0.526, p = .001). We conclude that iron and hs-CRP are elevated and adiponectin is reduced in BPH cases and associated with prostate size. © 2016 Blackwell Verlag GmbH.
A supervoxel-based segmentation method for prostate MR images.
Tian, Zhiqiang; Liu, Lizhi; Zhang, Zhenfeng; Xue, Jianru; Fei, Baowei
2017-02-01
Segmentation of the prostate on MR images has many applications in prostate cancer management. In this work, we propose a supervoxel-based segmentation method for prostate MR images. A supervoxel is a set of pixels that have similar intensities, locations, and textures in a 3D image volume. The prostate segmentation problem is considered as assigning a binary label to each supervoxel, which is either the prostate or background. A supervoxel-based energy function with data and smoothness terms is used to model the label. The data term estimates the likelihood of a supervoxel belonging to the prostate by using a supervoxel-based shape feature. The geometric relationship between two neighboring supervoxels is used to build the smoothness term. The 3D graph cut is used to minimize the energy function to get the labels of the supervoxels, which yields the prostate segmentation. A 3D active contour model is then used to get a smooth surface by using the output of the graph cut as an initialization. The performance of the proposed algorithm was evaluated on 30 in-house MR image data and PROMISE12 dataset. The mean Dice similarity coefficients are 87.2 ± 2.3% and 88.2 ± 2.8% for our 30 in-house MR volumes and the PROMISE12 dataset, respectively. The proposed segmentation method yields a satisfactory result for prostate MR images. The proposed supervoxel-based method can accurately segment prostate MR images and can have a variety of application in prostate cancer diagnosis and therapy. © 2016 American Association of Physicists in Medicine.
Prevalence of prostatitis-like symptoms in a managed care population.
Clemens, J Quentin; Meenan, Richard T; O'Keeffe-Rosetti, Maureen C; Gao, Sara Y; Brown, Sheila O; Calhoun, Elizabeth A
2006-08-01
We calculated the prevalence of symptoms typically associated with chronic prostatitis/chronic pelvic pain syndrome in men in a managed care population in the Pacific Northwest. A questionnaire mailing to 5,000 male enrollees 25 to 80 years old in the Kaiser Permanente Northwest (Portland, Oregon) health plan was performed. The questionnaires included screening questions about the presence, duration and severity of pelvic pain, and the National Institutes of Health Chronic Prostatitis Symptom Index. Chronic prostatitis/chronic pelvic pain syndrome symptoms were defined in 2 ways: 1) presence of any of the following for a duration of 3 or more months: pain in the perineum, testicles, tip of penis, pubic or bladder area, dysuria, ejaculatory pain; and 2) perineal and/or ejaculatory pain, and a National Institutes of Health Chronic Prostatitis Symptom Index total pain score of 4 or more. Prevalence estimates were age adjusted to the total Kaiser Permanente Northwest male population. A total of 1,550 questionnaires were returned. The prevalence of chronic prostatitis/chronic pelvic pain syndrome symptoms was 7.5% for definition 1 and 5.9% for definition 2. Mean National Institutes of Health Chronic Prostatitis Symptom Index scores were 17 for definitions 1 and 2. Of those with prostatitis-like symptoms, 30% met criteria for having both definitions present. The prevalence of prostatitis-like symptoms using either of the 2 diagnoses was 11.2%. This population based study indicates that approximately 1 in 9 men have prostatitis-like symptoms. Application of 2 different definitions for prostatitis-like symptoms identified unique groups of men, with limited overlap in the groups.
Dose calculation of dynamic trajectory radiotherapy using Monte Carlo.
Manser, P; Frauchiger, D; Frei, D; Volken, W; Terribilini, D; Fix, M K
2018-04-06
Using volumetric modulated arc therapy (VMAT) delivery technique gantry position, multi-leaf collimator (MLC) as well as dose rate change dynamically during the application. However, additional components can be dynamically altered throughout the dose delivery such as the collimator or the couch. Thus, the degrees of freedom increase allowing almost arbitrary dynamic trajectories for the beam. While the dose delivery of such dynamic trajectories for linear accelerators is technically possible, there is currently no dose calculation and validation tool available. Thus, the aim of this work is to develop a dose calculation and verification tool for dynamic trajectories using Monte Carlo (MC) methods. The dose calculation for dynamic trajectories is implemented in the previously developed Swiss Monte Carlo Plan (SMCP). SMCP interfaces the treatment planning system Eclipse with a MC dose calculation algorithm and is already able to handle dynamic MLC and gantry rotations. Hence, the additional dynamic components, namely the collimator and the couch, are described similarly to the dynamic MLC by defining data pairs of positions of the dynamic component and the corresponding MU-fractions. For validation purposes, measurements are performed with the Delta4 phantom and film measurements using the developer mode on a TrueBeam linear accelerator. These measured dose distributions are then compared with the corresponding calculations using SMCP. First, simple academic cases applying one-dimensional movements are investigated and second, more complex dynamic trajectories with several simultaneously moving components are compared considering academic cases as well as a clinically motivated prostate case. The dose calculation for dynamic trajectories is successfully implemented into SMCP. The comparisons between the measured and calculated dose distributions for the simple as well as for the more complex situations show an agreement which is generally within 3% of the maximum dose or 3mm. The required computation time for the dose calculation remains the same when the additional dynamic moving components are included. The results obtained for the dose comparisons for simple and complex situations suggest that the extended SMCP is an accurate dose calculation and efficient verification tool for dynamic trajectory radiotherapy. This work was supported by Varian Medical Systems. Copyright © 2018. Published by Elsevier GmbH.
NASA Technical Reports Server (NTRS)
Engelland, Shawn A.; Capps, Alan
2011-01-01
Current aircraft departure release times are based on manual estimates of aircraft takeoff times. Uncertainty in takeoff time estimates may result in missed opportunities to merge into constrained en route streams and lead to lost throughput. However, technology exists to improve takeoff time estimates by using the aircraft surface trajectory predictions that enable air traffic control tower (ATCT) decision support tools. NASA s Precision Departure Release Capability (PDRC) is designed to use automated surface trajectory-based takeoff time estimates to improve en route tactical departure scheduling. This is accomplished by integrating an ATCT decision support tool with an en route tactical departure scheduling decision support tool. The PDRC concept and prototype software have been developed, and an initial test was completed at air traffic control facilities in Dallas/Fort Worth. This paper describes the PDRC operational concept, system design, and initial observations.
NASA Technical Reports Server (NTRS)
Lane, John E.; Kasparis, Takis; Jones, W. Linwood; Metzger, Philip T.
2009-01-01
Methodologies to improve disdrometer processing, loosely based on mathematical techniques common to the field of particle flow and fluid mechanics, are examined and tested. The inclusion of advection and vertical wind field estimates appear to produce significantly improved results in a Lagrangian hydrometeor trajectory model, in spite of very strict assumptions of noninteracting hydrometeors, constant vertical air velocity, and time independent advection during the scan time interval. Wind field data can be extracted from each radar elevation scan by plotting and analyzing reflectivity contours over the disdrometer site and by collecting the radar radial velocity data to obtain estimates of advection. Specific regions of disdrometer spectra (drop size versus time) often exhibit strong gravitational sorting signatures, from which estimates of vertical velocity can be extracted. These independent wind field estimates become inputs and initial conditions to the Lagrangian trajectory simulation of falling hydrometeors.
Prostate contouring in MRI guided biopsy.
Vikal, Siddharth; Haker, Steven; Tempany, Clare; Fichtinger, Gabor
2009-03-27
With MRI possibly becoming a modality of choice for detection and staging of prostate cancer, fast and accurate outlining of the prostate is required in the volume of clinical interest. We present a semi-automatic algorithm that uses a priori knowledge of prostate shape to arrive at the final prostate contour. The contour of one slice is then used as initial estimate in the neighboring slices. Thus we propagate the contour in 3D through steps of refinement in each slice. The algorithm makes only minimum assumptions about the prostate shape. A statistical shape model of prostate contour in polar transform space is employed to narrow search space. Further, shape guidance is implicitly imposed by allowing only plausible edge orientations using template matching. The algorithm does not require region-homogeneity, discriminative edge force, or any particular edge profile. Likewise, it makes no assumption on the imaging coils and pulse sequences used and it is robust to the patient's pose (supine, prone, etc.). The contour method was validated using expert segmentation on clinical MRI data. We recorded a mean absolute distance of 2.0 ± 0.6 mm and dice similarity coefficient of 0.93 ± 0.3 in midsection. The algorithm takes about 1 second per slice.
Prostate contouring in MRI guided biopsy
Vikal, Siddharth; Haker, Steven; Tempany, Clare; Fichtinger, Gabor
2010-01-01
With MRI possibly becoming a modality of choice for detection and staging of prostate cancer, fast and accurate outlining of the prostate is required in the volume of clinical interest. We present a semi-automatic algorithm that uses a priori knowledge of prostate shape to arrive at the final prostate contour. The contour of one slice is then used as initial estimate in the neighboring slices. Thus we propagate the contour in 3D through steps of refinement in each slice. The algorithm makes only minimum assumptions about the prostate shape. A statistical shape model of prostate contour in polar transform space is employed to narrow search space. Further, shape guidance is implicitly imposed by allowing only plausible edge orientations using template matching. The algorithm does not require region-homogeneity, discriminative edge force, or any particular edge profile. Likewise, it makes no assumption on the imaging coils and pulse sequences used and it is robust to the patient's pose (supine, prone, etc.). The contour method was validated using expert segmentation on clinical MRI data. We recorded a mean absolute distance of 2.0 ± 0.6 mm and dice similarity coefficient of 0.93 ± 0.3 in midsection. The algorithm takes about 1 second per slice. PMID:21132083
Benejam-Gual, J M; Sanz-Granda, A; García-Miralles Grávalos, R; Severa-Ruíz de Velasco, A; Pons-Viver, J
2014-05-01
Transurethral resection of the prostate is the gold standard of surgical treatment of lower urinary tract symptoms associated to benign prostate hyperplasia. The new Green Light Photovaporization has been shown to be an alternative that is as effective for this condition as the transurethral resection of the prostate. To compare the efficiency of Green Light Photovaporization 120 W versus transurethral resection of the prostate in the treatment of benign prostate hyperplasia (BPH) in a 2-year time horizon from the perspective of the Spanish health service perspective. A cost utility analysis was performed retrospectively with the data from 98 patients treated sequentially with transurethral resection of the prostate (n: 50) and Green Light Photovaporization 120 W (n: 48). A Markov model was designed to estimate the cost (2012€) and results (quality adjusted life years) in a 2-year time horizon. The total cost associated to Green Light Photovaporization 120 W treatment was less (3,377€; 95% CI: 3,228; 3,537) than that of the transurethral resection of the prostate (3,770€; 95% CI: 3,579; 3,945). The determining factor of the cost was the surgical phase (difference: -450€; 95% CI: -625; -158) because admission to hospital after surgery was not necessary with the GreenLight-PhotoVaporization. Surgical treatment of BPH patients with GreenLight-PhotoVaporization 120 W is more efficient than transurethral resection of the prostate in the surgical treatment of benign prostate hyperplasia as it has similar effectiveness and lower cost (-393€; 95% CI: -625; -158). Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.
Yang, Xiaoli; Li, Hongtao; Zhang, Chengdong; Lin, Zhidi; Zhang, Xinhua; Zhang, Youjie; Yu, Yanbao; Liu, Kun; Li, Muyan; Zhang, Yuening; Lv, Wenxin; Xie, Yuanliang; Lu, Zheng; Wu, Chunlei; Teng, Ruobing; Lu, Shaoming; He, Min; Mo, Zengnan
2015-10-01
Prostatitis is one of the most common urological problems afflicting adult men. The etiology and pathogenesis of nonbacterial prostatitis, which accounts for 90-95% of cases, is largely unknown. As serum proteins often indicate the overall pathologic status of patients, we hypothesized that protein biomarkers of prostatitis might be identified by comparing the serum proteomes of patients with and without nonbacterial prostatitis. All untreated samples were collected from subjects attending the Fangchenggang Area Male Health and Examination Survey (FAMHES). We profiled pooled serum samples from four carefully selected groups of patients (n = 10/group) representing the various categories of nonbacterial prostatitis (IIIa, IIIb, and IV) and matched healthy controls using a mass spectrometry-based 4-plex iTRAQ proteomic approach. More than 160 samples were validated by ELISA. Overall, 69 proteins were identified. Among them, 42, 52, and 37 proteins were identified with differential expression in Category IIIa, IIIb, and IV prostatitis, respectively. The 19 common proteins were related to immunity and defense, ion binding, transport, and proteolysis. Two zinc-binding proteins, superoxide dismutase 3 (SOD3), and carbonic anhydrase I (CA1), were significantly higher in all types of prostatitis than in the control. A receiver operating characteristic curve estimated sensitivities of 50.4 and 68.1% and specificities of 92.1 and 83.8% for CA1 and SOD3, respectively, in detecting nonbacterial prostatitis. The serum CA1 concentration was inversely correlated to the zinc concentration in expressed-prostatic secretions. Our findings suggest that SOD3 and CA1 are potential diagnostic markers of nonbacterial prostatitis, although further large-scale studies are required. The molecular profiles of nonbacterial prostatitis pathogenesis may lay a foundation for discovery of new therapies. © 2015 Wiley Periodicals, Inc.
Słapa, Rafał Z.; Jakubowski, Wiesław S.; Migda, Bartosz; Dmowski, Tadeusz
2014-01-01
Aim Sonoelastography is a technique that assesses tissue hardness/compressibility. Utility and sensitivity of the method in prostate cancer diagnostics were assessed compared to the current gold standard in prostate cancer diagnostics i.e. systematic biopsy. Material and methods The study involved 84 patients suspected of prostate cancer based on elevated PSA levels or abnormal per rectal examination findings. Sonoelastography was used to evaluate the prostate gland. In the case of regions with hardness two-fold greater than that of symmetric prostate area (strain ratio >2), targeted biopsy was used; which was followed by an ultrasound-guided 8- or 10-core systematic biopsy (regardless of sonoelastography-indicated sites) as a reference point. Results The mean age of patients was 69 years. PSA serum levels ranged between 1.02 and 885 ng/dl. The mean prostate volume was 62 ml (19–149 ml). Prostate cancer was found in 39 out of 84 individuals. Statistically significant differences in strain ratios between cancers and benign lesions were shown. Sonoelastography guided biopsy revealed 30 lesions – overall sensitivity 77% (sensitivity of the method – 81%). Sonoelastographic sensitivity increased depending on cancer stage according to the Gleason grading system: 6–60%, 7–75%, 8–83%, 9/10–100%. The estimated sensitivity of systematic biopsy was 92%. Conclusions Sonoelastography shows higher diagnostic sensitivity in prostate cancer diagnostics compared to conventional imaging techniques, i.e. grey-scale TRUS, Doppler ultrasound. It allows to reduce the number of collected tissue cores, and thus limit the incidence of complications as well as the costs involved. Sonoelastography using the determination of compressibility ratio for symmetrical prostatic regions may prove useful in the detection of clinically significant prostate cancer. PMID:26674065
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Hao; Mey, Antonia S. J. S.; Noé, Frank
2014-12-07
We propose a discrete transition-based reweighting analysis method (dTRAM) for analyzing configuration-space-discretized simulation trajectories produced at different thermodynamic states (temperatures, Hamiltonians, etc.) dTRAM provides maximum-likelihood estimates of stationary quantities (probabilities, free energies, expectation values) at any thermodynamic state. In contrast to the weighted histogram analysis method (WHAM), dTRAM does not require data to be sampled from global equilibrium, and can thus produce superior estimates for enhanced sampling data such as parallel/simulated tempering, replica exchange, umbrella sampling, or metadynamics. In addition, dTRAM provides optimal estimates of Markov state models (MSMs) from the discretized state-space trajectories at all thermodynamic states. Under suitablemore » conditions, these MSMs can be used to calculate kinetic quantities (e.g., rates, timescales). In the limit of a single thermodynamic state, dTRAM estimates a maximum likelihood reversible MSM, while in the limit of uncorrelated sampling data, dTRAM is identical to WHAM. dTRAM is thus a generalization to both estimators.« less
Underwood, Marion K; Beron, Kurt J; Rosen, Lisa H
2009-01-01
For a sample followed from age 9-13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression.
Underwood, Marion K.; Beron, Kurt J.; Rosen, Lisa H.
2009-01-01
For a sample followed from age 9–13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression. PMID:19685551
Estimating Basic Preliminary Design Performances of Aerospace Vehicles
NASA Technical Reports Server (NTRS)
Luz, Paul L.; Alexander, Reginald
2004-01-01
Aerodynamics and Performance Estimation Toolset is a collection of four software programs for rapidly estimating the preliminary design performance of aerospace vehicles represented by doing simplified calculations based on ballistic trajectories, the ideal rocket equation, and supersonic wedges through standard atmosphere. The program consists of a set of Microsoft Excel worksheet subprograms. The input and output data are presented in a user-friendly format, and calculations are performed rapidly enough that the user can iterate among different trajectories and/or shapes to perform "what-if" studies. Estimates that can be computed by these programs include: 1. Ballistic trajectories as a function of departure angles, initial velocities, initial positions, and target altitudes; assuming point masses and no atmosphere. The program plots the trajectory in two-dimensions and outputs the position, pitch, and velocity along the trajectory. 2. The "Rocket Equation" program calculates and plots the trade space for a vehicle s propellant mass fraction over a range of specific impulse and mission velocity values, propellant mass fractions as functions of specific impulses and velocities. 3. "Standard Atmosphere" will estimate the temperature, speed of sound, pressure, and air density as a function of altitude in a standard atmosphere, properties of a standard atmosphere as functions of altitude. 4. "Supersonic Wedges" will calculate the free-stream, normal-shock, oblique-shock, and isentropic flow properties for a wedge-shaped body flying supersonically through a standard atmosphere. It will also calculate the maximum angle for which a shock remains attached, and the minimum Mach number for which a shock becomes attached, all as functions of the wedge angle, altitude, and Mach number.
Integrating animal movement with habitat suitability for estimating dynamic landscape connectivity
van Toor, Mariëlle L.; Kranstauber, Bart; Newman, Scott H.; Prosser, Diann J.; Takekawa, John Y.; Technitis, Georgios; Weibel, Robert; Wikelski, Martin; Safi, Kamran
2018-01-01
Context High-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of importance. Objectives We introduce an approach that combines movement-informed simulated trajectories with an environment-informed estimate of the trajectories’ plausibility to derive connectivity. Using the example of bar-headed geese we estimated migratory connectivity at a landscape level throughout the annual cycle in their native range. Methods We used tracking data of bar-headed geese to develop a multi-state movement model and to estimate temporally explicit habitat suitability within the species’ range. We simulated migratory movements between range fragments, and calculated a measure we called route viability. The results are compared to expectations derived from published literature. Results Simulated migrations matched empirical trajectories in key characteristics such as stopover duration. The viability of the simulated trajectories was similar to that of the empirical trajectories. We found that, overall, the migratory connectivity was higher within the breeding than in wintering areas, corroborating previous findings for this species. Conclusions We show how empirical tracking data and environmental information can be fused for meaningful predictions of animal movements throughout the year and even outside the spatial range of the available data. Beyond predicting migratory connectivity, our framework will prove useful for modelling ecological processes facilitated by animal movement, such as seed dispersal or disease ecology.
Maeda, Yoshikazu; Sato, Yoshitaka; Minami, Hiroki; Yasukawa, Yutaka; Yamamoto, Kazutaka; Tamamura, Hiroyasu; Shibata, Satoshi; Bou, Sayuri; Sasaki, Makoto; Tameshige, Yuji; Kume, Kyo; Ooto, Hiroshi; Kasahara, Shigeru; Shimizu, Yasuhiro; Saga, Yusuke; Omoya, Akira; Saitou, Makoto
2018-05-01
To evaluate the effectiveness of CT image-guided proton radiotherapy for prostate cancer by analyzing the positioning uncertainty and assessing daily dose change due to anatomical variations. Patients with prostate cancer were treated by opposed lateral proton beams based on a passive scattering method using an in-room CT image-guided system. The system employs a single couch for both CT scanning and beam delivery. The patient was positioned by matching the boundary between the prostate and the rectum's anterior region identified in the CT images to the corresponding boundary in the simulator images after bone matching. We acquired orthogonal kV x-ray images after couch movement and confirmed the body position by referring to the bony structure prior to treatment. In offline analyses, we contoured the targeted anatomical structures on 375 sets of daily in-room CT images for 10 patients. The uncertainty of the image-matching procedure was evaluated using the prostate contours and actual couch corrections. We also performed dose calculations using the same set of CT images, and evaluated daily change of dose-volume histograms (DVHs) to compare the effectiveness of the treatment using prostate matching to the bone-matching procedure. The isocenter shifts by prostate matching after bone matching were 0.5 ± 1.8 and -0.8 ± 2.6 mm along the superior-inferior (SI) and anterior-posterior (AP) directions, respectively. The body movement errors (σ) after couch movement were 0.7, 0.5, and 0.3 mm along the lateral, SI and AP direction, respectively, for 30 patients. The estimated errors (σ) in the prostate matching were 1.0 and 1.3 mm, and, in conjunction with the movement errors, the total positioning uncertainty was estimated to be 1.0 and 1.4 mm along the SI and AP directions, respectively. Daily DVH analyses showed that in the prostate matching, 98.7% and 86.1% of the total 375 irradiations maintained a dose condition of V 95% > 95% for the prostate and a dose constraint of V 77% < 18% for the rectum, whereas 90.4% and 66.1% of the total irradiations did so when bone matching was used. The dose constraint of the rectum and dose coverage of the prostate were better maintained by prostate matching than bone matching (P < 0.001). The daily variation in the dose to the seminal vesicles (SVs) was large, and only 40% of the total irradiations maintained the initial planned values of V 95% for high-risk treatment. Nevertheless, the deviations from the original value were -4 ± 7% and -5 ± 11% in the prostate and bone matching, respectively, and a better dose coverage of the SV was achieved by the prostate matching. The correction of repositioning along the AP and SI direction from conventional bone matching in CT image-guided proton therapy was found to be effective to maintain the dose constraint of the rectum and the dose coverage of the prostate. This work indicated that prostate cancer treatment by prostate matching using CT image guidance may be effective to reduce the rectal complications and achieve better tumor control of the prostate. However, an adaptive approach is desirable to maintain better dose coverage of the SVs. © 2018 American Association of Physicists in Medicine.
An RBF-PSO based approach for modeling prostate cancer
NASA Astrophysics Data System (ADS)
Perracchione, Emma; Stura, Ilaria
2016-06-01
Prostate cancer is one of the most common cancers in men; it grows slowly and it could be diagnosed in an early stage by dosing the Prostate Specific Antigen (PSA). However, a relapse after the primary therapy could arise in 25 - 30% of cases and different growth characteristics of the new tumor are observed. In order to get a better understanding of the phenomenon, a two parameters growth model is considered. To estimate the parameters values identifying the disease risk level a novel approach, based on combining Particle Swarm Optimization (PSO) with meshfree interpolation methods, is proposed.
Advanced methods of structural and trajectory analysis for transport aircraft
NASA Technical Reports Server (NTRS)
Ardema, Mark D.
1995-01-01
This report summarizes the efforts in two areas: (1) development of advanced methods of structural weight estimation, and (2) development of advanced methods of trajectory optimization. The majority of the effort was spent in the structural weight area. A draft of 'Analytical Fuselage and Wing Weight Estimation of Transport Aircraft', resulting from this research, is included as an appendix.
Multi-Target Tracking via Mixed Integer Optimization
2016-05-13
solving these two problems separately, however few algorithms attempt to solve these simultaneously and even fewer utilize optimization. In this paper we...introduce a new mixed integer optimization (MIO) model which solves the data association and trajectory estimation problems simultaneously by minimizing...Kalman filter [5], which updates the trajectory estimates before the algorithm progresses forward to the next scan. This process repeats sequentially
NASA Astrophysics Data System (ADS)
Latypov, A. F.
2008-12-01
Fuel economy at boost trajectory of the aerospace plane was estimated during energy supply to the free stream. Initial and final flight velocities were specified. The model of a gliding flight above cold air in an infinite isobaric thermal wake was used. The fuel consumption rates were compared at optimal trajectory. The calculations were carried out using a combined power plant consisting of ramjet and liquid-propellant engine. An exergy model was built in the first part of the paper to estimate the ramjet thrust and specific impulse. A quadratic dependence on aerodynamic lift was used to estimate the aerodynamic drag of aircraft. The energy for flow heating was obtained at the expense of an equivalent reduction of the exergy of combustion products. The dependencies were obtained for increasing the range coefficient of cruise flight for different Mach numbers. The second part of the paper presents a mathematical model for the boost interval of the aircraft flight trajectory and the computational results for the reduction of fuel consumption at the boost trajectory for a given value of the energy supplied in front of the aircraft.
Khan, Muhammad Sohaib; Khan, Bilal Masood; Naz, Sumbul; Pirzada, Muhammad Taqi
2013-02-15
Operative management of all gunshot's traumas carries a high rate of unwarranted interventions that are known to cause serious complications. Selective nonoperative management is thus being increasingly practiced which has reduced these avoidable interventions. Physical examination and computed tomography scans are most sensitive in assessing need of laparotomy. Assessment of internal injuries on the basis of an estimated bullet trajectory is often practiced but has seldom been studied. We report a case of conservative management of a thoraco abdominal gun shot patient where an estimated bullet trajectory was indicative of serious injuries. To the best of our knowledge this is the first report of a thoraco abdominal gunshot that, despite of a protracted trajectory, had no sequelae and was thus managed nonoperatively. A 30 year old male patient having height of 180 cm and weight of 70 kg (Body Mass Index 21.6) presented with complaint of a penetrating injury at left side of upper torso. The patient had no symptoms or obvious bleeding and was vitally stable. On examination a 1 cm × 1 cm entry wound at the left 3rd intercostal space in the mid clavicular line was identified. The chest and abdomen were otherwise unremarkable on examination. The chest radiograph displayed clear lung fields. The abdominal radiographs displayed a bullet in the upper left quadrant of the abdomen lateral to the spine. The bullets estimated trajectory from 3rd intercostal space and its lodgment in the abdomen lateral to the spine indicated severe visceral injury. The computed tomography scan showed that the bullet was lodged postero-medially to the left kidney. All thoracic, intra peritoneal and retroperitoneal visceral structures were identified to be normal. The patient remained clinically and vitally stable, hence was managed nonoperatively being discharged after 48 h of observation. From this case we conclude that decision for managing gun shot patients should be based on objective clinical and diagnostic findings. We recommend further investigation of the predictability of estimated trajectory for visceral injuries and consequent operative intervention as we found it to be misleading in this case.
2013-01-01
Background Operative management of all gunshot’s traumas carries a high rate of unwarranted interventions that are known to cause serious complications. Selective nonoperative management is thus being increasingly practiced which has reduced these avoidable interventions. Physical examination and computed tomography scans are most sensitive in assessing need of laparotomy. Assessment of internal injuries on the basis of an estimated bullet trajectory is often practiced but has seldom been studied. We report a case of conservative management of a thoraco abdominal gun shot patient where an estimated bullet trajectory was indicative of serious injuries. To the best of our knowledge this is the first report of a thoraco abdominal gunshot that, despite of a protracted trajectory, had no sequelae and was thus managed nonoperatively. Case presentation A 30 year old male patient having height of 180 cm and weight of 70 kg (Body Mass Index 21.6) presented with complaint of a penetrating injury at left side of upper torso. The patient had no symptoms or obvious bleeding and was vitally stable. On examination a 1 cm × 1 cm entry wound at the left 3rd intercostal space in the mid clavicular line was identified. The chest and abdomen were otherwise unremarkable on examination. The chest radiograph displayed clear lung fields. The abdominal radiographs displayed a bullet in the upper left quadrant of the abdomen lateral to the spine. The bullets estimated trajectory from 3rd intercostal space and its lodgment in the abdomen lateral to the spine indicated severe visceral injury. The computed tomography scan showed that the bullet was lodged postero-medially to the left kidney. All thoracic, intra peritoneal and retroperitoneal visceral structures were identified to be normal. The patient remained clinically and vitally stable, hence was managed nonoperatively being discharged after 48 h of observation. Conclusion From this case we conclude that decision for managing gun shot patients should be based on objective clinical and diagnostic findings. We recommend further investigation of the predictability of estimated trajectory for visceral injuries and consequent operative intervention as we found it to be misleading in this case. PMID:23414905
Hughes, Lucinda; Ruth, Karen; Rebbeck, Timothy R.; Giri, Veda N.
2013-01-01
Background Men with a family history of prostate cancer and African American men are at high risk for prostate cancer and in need of personalized risk estimates to inform screening decisions. This study evaluated genetic variants in genes encoding microRNA (miRNA) binding sites for informing of time to prostate cancer diagnosis among ethnically-diverse, high-risk men undergoing prostate cancer screening. Methods The Prostate Cancer Risk Assessment Program (PRAP) is a longitudinal screening program for high-risk men. Eligibility includes men ages 35-69 with a family history of prostate cancer or African descent. Participants with ≥ 1 follow-up visit were included in the analyses (n=477). Genetic variants in regions encoding miRNA binding sites in four target genes (ALOX15, IL-16, IL-18, and RAF1) previously implicated in prostate cancer development were evaluated. Genotyping methods included Taqman® SNP Genotyping Assay (Applied Biosystems) or pyrosequencing. Cox models were used to assess time to prostate cancer diagnosis by risk genotype. Results Among 256 African Americans with ≥ one follow-up visit, the TT genotype at rs1131445 in IL-16 was significantly associated with earlier time to prostate cancer diagnosis vs. the CC/CT genotypes (p=0.013), with a suggestive association after correction for false-discovery (p=0.065). Hazard ratio after controlling for age and PSA for TT vs. CC/CT among African Americans was 3.0 (95% CI 1.26-7.12). No association to time to diagnosis was detected among Caucasians by IL-16 genotype. No association to time to prostate cancer diagnosis was found for the other miRNA target genotypes. Conclusions Genetic variation in IL-16 encoding miRNA target site may be informative of time to prostate cancer diagnosis among African American men enrolled in prostate cancer risk assessment, which may inform individualized prostate cancer screening strategies in the future. PMID:24061634
Davidsson, Sabina; Andren, Ove; Ohlson, Anna-Lena; Carlsson, Jessica; Andersson, Swen-Olof; Giunchi, Francesca; Rider, Jennifer R; Fiorentino, Michelangelo
2018-01-01
The tumor promoting or counteracting effects of the immune response to cancer development are thought to be mediated to some extent by the infiltration of regulatory T cells (T regs ). In the present study we evaluated the prevalence of T reg populations in stromal and epithelial compartments of normal, post atrophic hyperplasia (PAH), prostatic intraepithelial neoplasia (PIN), and tumor lesions in men with and without prostate cancer. Study subjects were 102 men consecutively diagnosed with localized prostate cancer undergoing radical prostatectomy and 38 men diagnosed with bladder cancer undergoing cystoprostatectomy without prostate cancer at the pathological examination. Whole mount sections from all patients were evaluated for the epithelial and stromal expression of CD4 + T regs and CD8 + T regs in normal, PAH, PIN, and tumor lesions. A Friedmańs test was used to investigate differences in the mean number of T regs across histological lesions. Logistic regression was used to estimate crude and adjusted odds ratios (OR) for prostate cancer for each histological area. In men with prostate cancer, similarly high numbers of stromal CD4 + T regs were identified in PAH and tumor, but CD4 + T regs were less common in PIN. Greater numbers of epithelial CD4+ T regs in normal prostatic tissue were positively associated with both Gleason score and pT-stage. We observed a fourfold increased risk of prostate cancer in men with epithelial CD4 + T regs in the normal prostatic tissue counterpart. Our results may suggest a possible pathway through which PAH develops directly into prostate cancer in the presence of CD4 + T regs and indicate that transformation of the anti-tumor immune response may be initiated even before the primary tumor is established. © 2017 The Authors. The Prostate Published by Wiley Periodicals Inc.
Radiosensitization in prostate cancer: mechanisms and targets
2013-01-01
Prostate cancer is the second most commonly diagnosed cancer in American men over the age of 45 years and is the third most common cause of cancer related deaths in American men. In 2012 it is estimated that 241,740 men will be diagnosed with prostate cancer and 28,170 men will succumb to prostate cancer. Currently, radiation therapy is one of the most common definitive treatment options for localized prostate cancer. However, significant number of patients undergoing radiation therapy will develop locally persistent/recurrent tumours. The varying response rates to radiation may be due to 1) tumor microenvironment, 2) tumor stage/grade, 3) modality used to deliver radiation, and 4) dose of radiation. Higher doses of radiation has not always proved to be effective and have been associated with increased morbidity. Compounds designed to enhance the killing effects of radiation, radiosensitizers, have been extensively investigated over the past decade. The development of radiosensitizing agents could improve survival, improve quality of life and reduce costs, thus benefiting both patients and healthcare systems. Herin, we shall review the role and mechanisms of various agents that can sensitize tumours, specifically prostate cancer. PMID:23351141
Kargar, Soudabeh; Borisch, Eric A; Froemming, Adam T; Kawashima, Akira; Mynderse, Lance A; Stinson, Eric G; Trzasko, Joshua D; Riederer, Stephen J
2018-05-01
To describe an efficient numerical optimization technique using non-linear least squares to estimate perfusion parameters for the Tofts and extended Tofts models from dynamic contrast enhanced (DCE) MRI data and apply the technique to prostate cancer. Parameters were estimated by fitting the two Tofts-based perfusion models to the acquired data via non-linear least squares. We apply Variable Projection (VP) to convert the fitting problem from a multi-dimensional to a one-dimensional line search to improve computational efficiency and robustness. Using simulation and DCE-MRI studies in twenty patients with suspected prostate cancer, the VP-based solver was compared against the traditional Levenberg-Marquardt (LM) strategy for accuracy, noise amplification, robustness to converge, and computation time. The simulation demonstrated that VP and LM were both accurate in that the medians closely matched assumed values across typical signal to noise ratio (SNR) levels for both Tofts models. VP and LM showed similar noise sensitivity. Studies using the patient data showed that the VP method reliably converged and matched results from LM with approximate 3× and 2× reductions in computation time for the standard (two-parameter) and extended (three-parameter) Tofts models. While LM failed to converge in 14% of the patient data, VP converged in the ideal 100%. The VP-based method for non-linear least squares estimation of perfusion parameters for prostate MRI is equivalent in accuracy and robustness to noise, while being more reliably (100%) convergent and computationally about 3× (TM) and 2× (ETM) faster than the LM-based method. Copyright © 2017 Elsevier Inc. All rights reserved.
Lansford, Jennifer E.; Malone, Patrick S.; Castellino, Domini R.; Dodge, Kenneth A.; Pettit, Gregory S.; Bates, John E.
2009-01-01
This study examined whether the occurrence and timing of parental separation or divorce was related to trajectories of academic grades and mother- and teacher-reported internalizing and externalizing problems. The authors used hierarchical linear models to estimate trajectories for children who did and did not experience their parents' divorce or separation in kindergarten through 10th grade (N = 194). A novel approach to analyzing the timing of divorce/separation was adopted, and trajectories were estimated from 1 year prior to the divorce/separation to 3 years after the event. Results suggest that early parental divorce/separation is more negatively related to trajectories of internalizing and externalizing problems than is later divorce/separation, whereas later divorce/separation is more negatively related to grades. One implication of these findings is that children may benefit most from interventions focused on preventing internalizing and externalizing problems, whereas adolescents may benefit most from interventions focused on promoting academic achievement. PMID:16756405
Lansford, Jennifer E; Malone, Patrick S; Castellino, Domini R; Dodge, Kenneth A; Pettit, Gregory S; Bates, John E
2006-06-01
This study examined whether the occurrence and timing of parental separation or divorce was related to trajectories of academic grades and mother- and teacher-reported internalizing and externalizing problems. The authors used hierarchical linear models to estimate trajectories for children who did and did not experience their parents' divorce or separation in kindergarten through 10th grade (N = 194). A novel approach to analyzing the timing of divorce/separation was adopted, and trajectories were estimated from 1 year prior to the divorce/separation to 3 years after the event. Results suggest that early parental divorce/separation is more negatively related to trajectories of internalizing and externalizing problems than is later divorce/separation, whereas later divorce/separation is more negatively related to grades. One implication of these findings is that children may benefit most from interventions focused on preventing internalizing and externalizing problems, whereas adolescents may benefit most from interventions focused on promoting academic achievement. ((c) 2006 APA, all rights reserved).
De Luca, Stefano; Passera, Roberto; Fiori, Cristian; Bollito, Enrico; Cappia, Susanna; Mario Scarpa, Roberto; Sottile, Antonino; Franco Randone, Donato; Porpiglia, Francesco
2015-10-01
To determine if prostate health index (PHI), prostate cancer antigen gene 3 (PCA3) score, and percentage of free prostate-specific antigen (%fPSA) may be used to differentiate asymptomatic acute and chronic prostatitis from prostate cancer (PCa), benign prostatic hyperplasia (BPH), and high-grade prostate intraepithelial neoplasia (HG-PIN) in patients with elevated PSA levels and negative findings on digital rectal examination at repeat biopsy (re-Bx). In this prospective study, 252 patients were enrolled, undergoing PHI, PCA3 score, and %fPSA assessments before re-Bx. We used 3 multivariate logistic regression models to test the PHI, PCA3 score, and %fPSA as risk factors for prostatitis vs. PCa, vs. BPH, and vs. HG-PIN. All the analyses were performed for the whole patient cohort and for the "gray zone" of PSA (4-10ng/ml) cohort (171 individuals). Of the 252 patients, 43 (17.1%) had diagnosis of PCa. The median PHI was significantly different between men with a negative biopsy and those with a positive biopsy (34.9 vs. 48.1, P<0.001), as for the PCA3 score (24 vs. 54, P<0.001) and %fPSA (11.8% vs. 15.8%, P = 0.012). The net benefit of using PCA3 and PHI to differentiate prostatitis and PCa was moderate, although it extended to a good range of threshold probabilities (40%-100%), whereas that from using %fPSA was negligible: this pattern was reported for the whole population as for the "gray zone" PSA cohort. In front of a good diagnostic performance of all the 3 biomarkers in distinguishing negative biopsy vs. positive biopsy, the clinical benefit of using the PCA3 score and PHI to estimate prostatitis vs. PCa was comparable. PHI was the only determinant for prostatitis vs. BPH, whereas no biomarkers could differentiate prostate inflammation from HG-PIN. Copyright © 2015 Elsevier Inc. All rights reserved.
Mancio, Jennifer; Leal, Cátia; Ferreira, Marta; Norton, Pedro; Lunet, Nuno
2018-04-27
Recent studies suggested that the relation between night-shift work and prostate cancer may differ between rotating and fixed schedules. We aimed to quantify the independent association between night-shift work and prostate cancer, for rotating and fixed schedules. We searched MEDLINE for studies assessing the association of night-shift work, by rotating or fixed schedules, with prostate cancer. We computed summary relative risk (RR) estimates with 95% confidence intervals (95% CI) using the inverse variance method and quantified heterogeneity using the I 2 statistic. Meta-regression analysis was used to compare the summary RR estimates for rotating and fixed schedules, while reducing heterogeneity. A total of nine studies assessed the effect of rotating and, in addition, four of them provided the effect of fixed night-shift work, in relation to daytime workers. Rotating night-shift work was associated with a significantly increased risk of prostate cancer (RR = 1.06, 95% CI of 1.01 to 1.12; I 2 = 50%), but not fixed night-shift work (RR of 1.01, 95% CI of 0.81 to 1.26; I 2 = 33%). In meta-regression model including study design, type of population, and control of confounding, the summary RR was 20% higher for rotating vs. fixed schedule, with heterogeneity fully explained by these variables. This is the first meta-analysis suggesting that an increased risk of prostate cancer may be restricted to workers with rotating night shifts. However, the association was weak and additional studies are needed to further clarify this relation before it can be translated into measures for risk reduction in occupational settings.
MSMB gene variant alters the association between prostate cancer and number of sexual partners
Stott-Miller, Marni; Wright, Jonathan L.; Stanford, Janet L.
2014-01-01
Background Recently, a genetic variant (rs10993994) in the MSMB gene associated with prostate cancer (PCa) risk was shown to correlate with reduced prostate secretory protein of 94 amino acids (PSP94) levels. Although the biological activity of PSP94 is unclear, one of its hypothesized functions is to protect prostatic cells from pathogens. Number of sexual partners and a history of sexually transmitted infections (STIs) have been positively associated with PCa risk, and these associations may be related to pathogen-induced chronic prostatic inflammation. Based on these observations, we investigated whether MSMB genotype modifies the PCa-sexual history association. Methods We estimated odds ratios (OR) and 95% confidence intervals (CI) for the association between number of sexual partners and PCa by fitting logistic regression models, stratified by MSMB genotype, and adjusted for age, family history of PCa, and PCa screening history among 1,239 incident cases and 1,232 controls. Results Compared with 1–4 female sexual partners, men with ≥15 such partners who carried the variant T allele of rs10993994 were at increased risk for PCa (OR=1.32; 95% CI, 1.03–1.71); no association was observed in men with the CC genotype (OR=1.03; 95% CI, 0.73–1.46; p=0.05 for interaction). Similar estimates were observed for total sexual partners (any T allele OR=1.37; 95% CI, 1.07–1.77; CC genotype OR=1.11; 95% CI, 0.79–1.55; p=0.06 for interaction). Conclusions The rs10993994 genotype in the MSMB gene modifies the association between number of sexual partners and PCa risk. These findings support a hypothesized biological mechanism whereby prostatic infection/inflammation may enhance risk of PCa. PMID:24037734
In vivo optoacoustic temperature imaging for image-guided cryotherapy of prostate cancer
NASA Astrophysics Data System (ADS)
Petrova, E. V.; Brecht, H. P.; Motamedi, M.; Oraevsky, A. A.; Ermilov, S. A.
2018-03-01
The objective of this study is to demonstrate in vivo the feasibility of optoacoustic temperature imaging during cryotherapy of prostate cancer. We developed a preclinical prototype optoacoustic temperature imager that included pulsed optical excitation at a wavelength of 805 nm, a modified clinical transrectal ultrasound probe, a parallel data acquisition system, image processing and visualization software. Cryotherapy of a canine prostate was performed in vivo using a commercial clinical system, Cryocare® CS, with an integrated ultrasound imaging. The universal temperature-dependent optoacoustic response of blood was employed to convert reconstructed optoacoustic images to temperature maps. Optoacoustic imaging of temperature during prostate cryotherapy was performed in the longitudinal view over a region of 30 mm (long) × 10 mm (deep) that covered the rectum, the Denonvilliers fascia, and the posterior portion of the treated gland. The transrectal optoacoustic images showed high-contrast vascularized regions, which were used for quantitative estimation of local temperature profiles. The constructed temperature maps and their temporal dynamics were consistent with the arrangement of the cryoprobe and readouts of the thermal needle sensors. The temporal profiles of the readouts from the thermal needle sensors and the temporal profile estimated from the normalized optoacoustic intensity of the selected vascularized region showed significant resemblance, except for the initial overshoot, that may be explained as a result of the physiological thermoregulatory compensation. The temperature was mapped with errors not exceeding ±2 °C (standard deviation) consistent with the clinical requirements for monitoring cryotherapy of the prostate. In vivo results showed that the optoacoustic temperature imaging is a promising non-invasive technique for real-time imaging of tissue temperature during cryotherapy of prostate cancer, which can be combined with transrectal ultrasound—the current standard for guiding clinical cryotherapy procedure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Falchook, Aaron D.; Salloum, Ramzi G.; Hendrix, Laura H.
Purpose: For patients with a high likelihood of having metastatic disease (high-risk prostate cancer), bone scan is the standard, guideline-recommended test to look for bony metastasis. We quantified the use of bone scans and downstream procedures, along with associated costs, in patients with high-risk prostate cancer, and their use in low- and intermediate-risk patients for whom these tests are not recommended. Methods and Materials: Patients in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database diagnosed with prostate cancer from 2004 to 2007 were included. Prostate specific antigen (PSA), Gleason score, and clinical T stage were used to define D'Amico riskmore » categories. We report use of bone scans from the date of diagnosis to the earlier of treatment or 6 months. In patients who underwent bone scans, we report use of bone-specific x-ray, computed tomography (CT), and magnetic resonance imaging (MRI) scans, and bone biopsy within 3 months after bone scan. Costs were estimated using 2012 Medicare reimbursement rates. Results: In all, 31% and 48% of patients with apparent low- and intermediate-risk prostate cancer underwent a bone scan; of these patients, 21% underwent subsequent x-rays, 7% CT, and 3% MRI scans. Bone biopsies were uncommon. Overall, <1% of low- and intermediate-risk patients were found to have metastatic disease. The annual estimated Medicare cost for bone scans and downstream procedures was $11,300,000 for low- and intermediate-risk patients. For patients with apparent high-risk disease, only 62% received a bone scan, of whom 14% were found to have metastasis. Conclusions: There is overuse of bone scans in patients with low- and intermediate-risk prostate cancers, which is unlikely to yield clinically actionable information and results in a potential Medicare waste. However, there is underuse of bone scans in high-risk patients for whom metastasis is likely.« less
Effects of pulsed electromagnetic fields on benign prostate hyperplasia.
Giannakopoulos, Xenophon K; Giotis, Christos; Karkabounas, Spyridon Ch; Verginadis, Ioannis I; Simos, Yannis V; Peschos, Dimitrios; Evangelou, Angelos M
2011-12-01
Benign prostate hyperplasia (BPH) has been treated with various types of electromagnetic radiation methods such as transurethral needle ablation (TUNA), interstitial laser therapy (ILC), holmium laser resection (HoLRP). In the present study, the effects of a noninvasive method based on the exposure of patients with BPH to a pulsative EM Field at radiofrequencies have been investigated. Twenty patients with BPH, aging 68-78 years old (y.o), were enrolled in the study. Patients were randomly divided into two groups: the treatment group (10 patients, 74.0 ± 5.7 y.o) treated with the α-blocker Alfusosin, 10 mg/24 h for at least 4 weeks, and the electromagnetic group (10 patients, 73.7 ± 6.3 y.o) exposed for 2 weeks in a very short wave duration, pulsed electromagnetic field at radiofrequencies generated by an ion magnetic inductor, for 30 min daily, 5 consecutive days per week. Patients of both groups were evaluated before and after drug and EMF treatment by values of total PSA and prostatic PSA fraction, acid phosphate, U/S estimation of prostate volume and urine residue, urodynamic estimation of urine flow rate, and International Prostate Symptom Score (IPSS). There was a statistically significant decrease before and after treatment of IPSS (P < 0.02), U/S prostate volume (P < 0.05), and urine residue (P < 0.05), as well as of mean urine flow rate (P < 0.05) in patients of the electromagnetic group, in contrast to the treatment group who had only improved IPSS (P < 0.05). There was also a significant improvement in clinical symptoms in patients of the electromagnetic group. Follow-up of the patients of this group for one year revealed that results obtained by EMFs treatment are still remaining. Pulsed electromagnetic field at radiofrequencies may benefit patients with benign prostate hyperplasia treated by a non-invasive method.
Lipiński, Marek I; Peszyński-Drews, Cezary; Jeromin, Marek Z; Jeromin, Leszek M
2006-01-01
Benign prostatic hyperplasia (BPH) exist in about 70% men after 60 years old. High power KTP laser is a new tool for the treatment of BPH. 49 men were treated by photoselective vaporisation of the prostate (PVP) from August 2003 to May 2004. Thirty patients with follow-up period longer than 12 weeks (12 to 26 weeks) were analyzed. Preoperative prostate volume ranged from 31 to 136 cc. PSA range, estimated before treatment, was normal in all patients (pts). International Prostate Symptom Score (I-PSS) estimated before treatment was over 24 and Quality of Life (QoL) was over 3 in all pts. The maximum peak urinary flow (Qmax) before treatment ranged from 7.2 to 14.1 ml/s. One patient was catheterized with Foley catheter at the finish of the procedure. Two pts required catheterization in the first day after treatment. In two pts increasing of body temperature to 38 degrees C was observed in the first day after treatment. Twenty four hours after treatment haematuria required catheterization was observed in one patient. Seven days after treatment in 4 pts massive haematuria was observed (two required hospitalisation). In one patient because of urinary retention 4 weeks after PVP transurethral resection of the prostate was performed. Four weeks after PVP I-PSS decreased from 24 to 20 and after 12 weeks to 15. The Qmax increased and ranged from 11.3 ml/s to 17.1 ml/s 4 weeks after PVP and 12 weeks after PVP ranged from 15.1 to 22.8 ml/s. Photoselective vaporization of the prostate reduces I-PSS in all patients 12 weeks after procedure. Short follow-up period and a limited number of patients in study group cannot lead to ultimate conclusions. However the results encourage to undertaking further studies on PVP for the treatment of BPH.
Prostate Mechanical Imaging: A New Method For Prostate Assessment
Weiss, Robert E; Egorov, Vladimir; Ayrapetyan, Suren; Sarvazyan, Noune; Sarvazyan, Armen
2008-01-01
Objectives To evaluate the ability of Prostate Mechanical Imaging (PMI) technology to provide an objective and reproducible image and to assess the prostate nodularity. Methods The PMI device developed by Artann Laboratories was evaluated in a pilot clinical study. For the 168 patients (ages 44 to 94) presented to an urologist for prostate evaluation, PMI-produced images and assessment of prostate size, shape, consistency/hardness, mobility, nodularity, and was compared with digital rectal examination (DRE) findings. The PMI and DRE results were further tested for correlation against a transrectal ultrasound of the prostate (TRUS) guided biopsy for a sub-group of 21 patients with an elevated PSA level. Results In 84% of the cases the PMI device was able to reconstruct 3-D and 2-D cross-sectional images of the prostate. The PMI System and DRE pre-tests were able to determine malignant nodules in 10 and 6 patients, respectively, of the 13 patients with biopsy-confirmed malignant inclusions. The PMI System findings were consistent with all 8 biopsy negative cases, while the DRE had 1 abnormal reading for this group. The correlation between PMI and DRE detection of palpable nodularity was 81%, as indicated by the area under the receiver operating characteristic (ROC) curve. Estimates of the prostate size provided by PMI and DRE were found to be statistically significantly correlated. Conclusions The PMI has the potential to enable a physician to obtain, examine and store a three dimensional image of the prostate based on mechanical and geometrical characteristics of the gland and its internal structures. PMID:18342178
Shelton, Jeremy B; Barocas, Daniel A; Conway, Frances; Hart, Kathleen; Nelson, Kinloch; Richstone, Lee; Gonzalez, Ricardo R; Raman, Jay D; Scherr, Douglas S
2005-05-01
To estimate the incidence of prostate cancer among African-American men and Caribbean immigrants to the United States, to assess the applicability of large-scale prostate screening trials to a community screening program, and to recruit unscreened men. African-American and Caribbean-American men were targeted with a community-based prostate cancer screening program in Jamaica, New York. Serum prostate-specific antigen determination and digital rectal examination were used to determine abnormal findings. The incidence of an abnormal screening examination was used to project the incidence of prostate cancer, which was compared with that in other reported trials. The projected incidence of prostate cancer among African-Americans and Caribbean-Americans older than 50 years was 8% and 7%, respectively, similar to that reported in other trials of African-American men. The projected incidence of prostate cancer in Caribbean-American men aged 40 to 49 years was 1%, the same as the high rate reported among Caribbean men. As in other trials, a family history of prostate cancer and age were strong predictors of abnormal findings. Of the recruited men older than 50 years, 58% had never been screened compared with 42% nationally. Large population-based screening trials have identified ethnic groups at high risk of prostate cancer. This trial detected high rates of abnormal screening findings by targeting ethnicity. The incidence of an abnormal examination was high in Caribbean-American men younger than 50 years old. Finally, this trial successfully recruited underscreened men.
Wiklund, Fredrik; Zheng, S. Lilly; Sun, Jielin; Adami, Hans-Olov; Lilja, Hans; Hsu, Fang-Chi; Stattin, Pär; Adolfsson, Jan; Cramer, Scott D.; Duggan, David; Carpten, John D.; Chang, Bao-Li; Isaacs, William B.; Grönberg, Henrik; Xu, Jianfeng
2012-01-01
BACKGROUND Prostate specific antigen (PSA) is widely used for prostate cancer screening but its levels are influenced by many non cancer-related factors. The goal of the study is to estimate the effect of genetic variants on PSA levels. METHODS We evaluated the association of SNPs that were reported to be associated with prostate cancer risk in recent genome-wide association studies with plasma PSA levels in a Swedish study population, including 1,722 control subjects without a diagnosis of prostate cancer. RESULTS Of the 16 SNPs analyzed in control subjects, significant associations with PSA levels (P≤0.05) were found for six SNPs. These six SNPs had a cumulative effect on PSA levels; the mean PSA levels in men were almost twofold increased across increasing quintile of number of PSA associated alleles, P-trend=3.4×10−14. In this Swedish study population risk allele frequencies were similar among T1c case patients (cancer detected by elevated PSA levels alone) as compared to T2 and above prostate cancer case patients. CONCLUSIONS Results from this study may have two important clinical implications. The cumulative effect of six SNPs on PSA levels suggests genetic-specific PSA cutoff values may be used to improve the discriminatory performance of this test for prostate cancer; and the dual associations of these SNPs with PSA levels and prostate cancer risk raise a concern that some of reported prostate cancer risk-associated SNPs may be confounded by the prevalent use of PSA screening. PMID:19116992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, B; Miften, M
2014-06-15
Purpose: Cone-beam CT (CBCT) projection images provide anatomical data in real-time over several respiratory cycles, forming a comprehensive picture of tumor movement. We developed a method using these projections to determine the trajectory and dose of highly mobile tumors during each fraction of treatment. Methods: CBCT images of a respiration phantom were acquired, where the trajectory mimicked a lung tumor with high amplitude (2.4 cm) and hysteresis. A template-matching algorithm was used to identify the location of a steel BB in each projection. A Gaussian probability density function for tumor position was calculated which best fit the observed trajectory ofmore » the BB in the imager geometry. Two methods to improve the accuracy of tumor track reconstruction were investigated: first, using respiratory phase information to refine the trajectory estimation, and second, using the Monte Carlo method to sample the estimated Gaussian tumor position distribution. 15 clinically-drawn abdominal/lung CTV volumes were used to evaluate the accuracy of the proposed methods by comparing the known and calculated BB trajectories. Results: With all methods, the mean position of the BB was determined with accuracy better than 0.1 mm, and root-mean-square (RMS) trajectory errors were lower than 5% of marker amplitude. Use of respiratory phase information decreased RMS errors by 30%, and decreased the fraction of large errors (>3 mm) by half. Mean dose to the clinical volumes was calculated with an average error of 0.1% and average absolute error of 0.3%. Dosimetric parameters D90/D95 were determined within 0.5% of maximum dose. Monte-Carlo sampling increased RMS trajectory and dosimetric errors slightly, but prevented over-estimation of dose in trajectories with high noise. Conclusions: Tumor trajectory and dose-of-the-day were accurately calculated using CBCT projections. This technique provides a widely-available method to evaluate highly-mobile tumors, and could facilitate better strategies to mitigate or compensate for motion during SBRT.« less
Amin Al Olama, Ali; Benlloch, Sara; Antoniou, Antonis C; Giles, Graham G; Severi, Gianluca; Neal, David E; Hamdy, Freddie C; Donovan, Jenny L; Muir, Kenneth; Schleutker, Johanna; Henderson, Brian E; Haiman, Christopher A; Schumacher, Fredrick R; Pashayan, Nora; Pharoah, Paul D P; Ostrander, Elaine A; Stanford, Janet L; Batra, Jyotsna; Clements, Judith A; Chambers, Suzanne K; Weischer, Maren; Nordestgaard, Børge G; Ingles, Sue A; Sorensen, Karina D; Orntoft, Torben F; Park, Jong Y; Cybulski, Cezary; Maier, Christiane; Doerk, Thilo; Dickinson, Joanne L; Cannon-Albright, Lisa; Brenner, Hermann; Rebbeck, Timothy R; Zeigler-Johnson, Charnita; Habuchi, Tomonori; Thibodeau, Stephen N; Cooney, Kathleen A; Chappuis, Pierre O; Hutter, Pierre; Kaneva, Radka P; Foulkes, William D; Zeegers, Maurice P; Lu, Yong-Jie; Zhang, Hong-Wei; Stephenson, Robert; Cox, Angela; Southey, Melissa C; Spurdle, Amanda B; FitzGerald, Liesel; Leongamornlert, Daniel; Saunders, Edward; Tymrakiewicz, Malgorzata; Guy, Michelle; Dadaev, Tokhir; Little, Sarah J; Govindasami, Koveela; Sawyer, Emma; Wilkinson, Rosemary; Herkommer, Kathleen; Hopper, John L; Lophatonanon, Aritaya; Rinckleb, Antje E; Kote-Jarai, Zsofia; Eeles, Rosalind A; Easton, Douglas F
2015-07-01
Genome-wide association studies have identified multiple genetic variants associated with prostate cancer risk which explain a substantial proportion of familial relative risk. These variants can be used to stratify individuals by their risk of prostate cancer. We genotyped 25 prostate cancer susceptibility loci in 40,414 individuals and derived a polygenic risk score (PRS). We estimated empirical odds ratios (OR) for prostate cancer associated with different risk strata defined by PRS and derived age-specific absolute risks of developing prostate cancer by PRS stratum and family history. The prostate cancer risk for men in the top 1% of the PRS distribution was 30.6 (95% CI, 16.4-57.3) fold compared with men in the bottom 1%, and 4.2 (95% CI, 3.2-5.5) fold compared with the median risk. The absolute risk of prostate cancer by age of 85 years was 65.8% for a man with family history in the top 1% of the PRS distribution, compared with 3.7% for a man in the bottom 1%. The PRS was only weakly correlated with serum PSA level (correlation = 0.09). Risk profiling can identify men at substantially increased or reduced risk of prostate cancer. The effect size, measured by OR per unit PRS, was higher in men at younger ages and in men with family history of prostate cancer. Incorporating additional newly identified loci into a PRS should improve the predictive value of risk profiles. We demonstrate that the risk profiling based on SNPs can identify men at substantially increased or reduced risk that could have useful implications for targeted prevention and screening programs. ©2015 American Association for Cancer Research.
Pham, Khanh N; Cullen, Jennifer; Hurwitz, Lauren M; Wolff, Erika M; Levie, Katherine E; Odem-Davis, Katherine; Banerji, John S; Rosner, Inger L; Brand, Timothy C; L'Esperance, James O; Sterbis, Joseph R; Porter, Christopher R
2016-08-01
Active surveillance is an important alternative to definitive therapy for men with low risk prostate cancer. However, the impact of active surveillance on health related quality of life compared to that in men without cancer remains unknown. In this study we evaluated health related quality of life outcomes in men on active surveillance compared to men followed after negative prostate needle biopsy. A prospective study was conducted on men who were enrolled into the Center for Prostate Disease Research Multicenter National Database and underwent prostate needle biopsy for suspicion of prostate cancer between 2007 and 2014. Health related quality of life was assessed at biopsy (baseline) and annually for up to 3 years using SF-36 and EPIC questionnaires. Health related quality of life scores were modeled using generalized estimating equations, adjusting for baseline health related quality of life, and demographic and clinical characteristics. Of the 1,204 men who met the initial eligibility criteria 420 had a negative prostate needle biopsy (noncancer comparison group). Among the 411 men diagnosed with low risk prostate cancer 89 were on active surveillance. Longitudinal analysis revealed that for most health related quality of life subscales there were no significant differences between the groups in adjusted health related quality of life score trends over time. In this study most health related quality of life outcomes in patients with low risk prostate cancer on active surveillance did not differ significantly from those of men without prostate cancer. A comparison group of men with a similar risk of prostate cancer detection is critical to clarify the psychological and physical impact of active surveillance. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
The Utility of PET/CT in the Planning of External Radiation Therapy for Prostate Cancer.
Calais, Jeremie; Cao, Minsong; Nickols, Nicholas G
2018-04-01
Radiotherapy and radical prostatectomy are the definitive treatment options for patients with localized prostate cancer. A rising level of prostate-specific antigen after radical prostatectomy indicates prostate cancer recurrence, and these patients may still be cured with salvage radiotherapy. To maximize chance for cure, the irradiated volumes should completely encompass the extent of disease. Therefore, accurate estimation of the location of disease is critical for radiotherapy planning in both the definitive and the salvage settings. Current first-line imaging for prostate cancer has limited sensitivity for detection of disease both at initial staging and at biochemical recurrence. Integration of PET into routine evaluation of prostate cancer patients may improve both staging accuracy and radiotherapy planning. 18 F-FDG PET/CT is now routinely used in radiation planning for several cancer types. However, 18 F-FDG PET/CT has low sensitivity for prostate cancer. Additional PET probes evaluated in prostate cancer include 18 F-sodium fluoride, 11 C-acetate, 11 C- or 18 F-choline, 18 F-fluciclovine, and 68 Ga- or 18 F-labeled ligands that bind prostate-specific membrane antigen (PSMA). PSMA ligands appear to be the most sensitive and specific but have not yet received Food and Drug Administration New Drug Application approval for use in the United States. Retrospective and prospective investigations suggest a potential major impact of PET/CT on prostate radiation treatment planning. Prospective trials randomizing patients to routine radiotherapy planning versus PET/CT-aided planning may show meaningful clinical outcomes. Prospective clinical trials evaluating the addition of 18 F-fluciclovine PET/CT for planning of salvage radiotherapy with clinical endpoints are under way. Prospective trials evaluating the clinical impact of PSMA PET/CT on prostate radiation planning are indicated. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.
Ebot, Ericka M; Gerke, Travis; Labbé, David P; Sinnott, Jennifer A; Zadra, Giorgia; Rider, Jennifer R; Tyekucheva, Svitlana; Wilson, Kathryn M; Kelly, Rachel S; Shui, Irene M; Loda, Massimo; Kantoff, Philip W; Finn, Stephen; Vander Heiden, Matthew G; Brown, Myles; Giovannucci, Edward L; Mucci, Lorelei A
2017-11-01
Obese men are at higher risk of advanced prostate cancer and cancer-specific mortality; however, the biology underlying this association remains unclear. This study examined gene expression profiles of prostate tissue to identify biological processes differentially expressed by obesity status and lethal prostate cancer. Gene expression profiling was performed on tumor (n = 402) and adjacent normal (n = 200) prostate tissue from participants in 2 prospective cohorts who had been diagnosed with prostate cancer from 1982 to 2005. Body mass index (BMI) was calculated from the questionnaire immediately preceding cancer diagnosis. Men were followed for metastases or prostate cancer-specific death (lethal disease) through 2011. Gene Ontology biological processes differentially expressed by BMI were identified using gene set enrichment analysis. Pathway scores were computed by averaging the signal intensities of member genes. Odds ratios (ORs) for lethal prostate cancer were estimated with logistic regression. Among 402 men, 48% were healthy weight, 31% were overweight, and 21% were very overweight/obese. Fifteen gene sets were enriched in tumor tissue, but not normal tissue, of very overweight/obese men versus healthy-weight men; 5 of these were related to chromatin modification and remodeling (false-discovery rate < 0.25). Patients with high tumor expression of chromatin-related genes had worse clinical characteristics (Gleason grade > 7, 41% vs 17%; P = 2 × 10 -4 ) and an increased risk of lethal disease that was independent of grade and stage (OR, 5.26; 95% confidence interval, 2.37-12.25). This study improves our understanding of the biology of aggressive prostate cancer and identifies a potential mechanistic link between obesity and prostate cancer death that warrants further study. Cancer 2017;123:4130-4138. © 2017 American Cancer Society. © 2017 American Cancer Society.
Petimar, Joshua; Wilson, Kathryn M; Wu, Kana; Wang, Molin; Albanes, Demetrius; van den Brandt, Piet A; Cook, Michael B; Giles, Graham G; Giovannucci, Edward L; Goodman, Gary E; Goodman, Phyllis J; Håkansson, Niclas; Helzlsouer, Kathy; Key, Timothy J; Kolonel, Laurence N; Liao, Linda M; Männistö, Satu; McCullough, Marjorie L; Milne, Roger L; Neuhouser, Marian L; Park, Yikyung; Platz, Elizabeth A; Riboli, Elio; Sawada, Norie; Schenk, Jeannette M; Tsugane, Shoichiro; Verhage, Bas; Wang, Ying; Wilkens, Lynne R; Wolk, Alicja; Ziegler, Regina G; Smith-Warner, Stephanie A
2017-08-01
Background: Relationships between fruit, vegetable, and mature bean consumption and prostate cancer risk are unclear. Methods: We examined associations between fruit and vegetable groups, specific fruits and vegetables, and mature bean consumption and prostate cancer risk overall, by stage and grade, and for prostate cancer mortality in a pooled analysis of 15 prospective cohorts, including 52,680 total cases and 3,205 prostate cancer-related deaths among 842,149 men. Diet was measured by a food frequency questionnaire or similar instrument at baseline. We calculated study-specific relative risks using Cox proportional hazards regression, and then pooled these estimates using a random effects model. Results: We did not observe any statistically significant associations for advanced prostate cancer or prostate cancer mortality with any food group (including total fruits and vegetables, total fruits, total vegetables, fruit and vegetable juice, cruciferous vegetables, and tomato products), nor specific fruit and vegetables. In addition, we observed few statistically significant results for other prostate cancer outcomes. Pooled multivariable relative risks comparing the highest versus lowest quantiles across all fruit and vegetable exposures and prostate cancer outcomes ranged from 0.89 to 1.09. There was no evidence of effect modification for any association by age or body mass index. Conclusions: Results from this large, international, pooled analysis do not support a strong role of collective groupings of fruits, vegetables, or mature beans in prostate cancer. Impact: Further investigation of other dietary exposures, especially indicators of bioavailable nutrient intake or specific phytochemicals, should be considered for prostate cancer risk. Cancer Epidemiol Biomarkers Prev; 26(8); 1276-87. ©2017 AACR . ©2017 American Association for Cancer Research.
An angle-dependent estimation of CT x-ray spectrum from rotational transmission measurements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Yuan, E-mail: yuan.lin@duke.edu; Samei, Ehsan; Ramirez-Giraldo, Juan Carlos
2014-06-15
Purpose: Computed tomography (CT) performance as well as dose and image quality is directly affected by the x-ray spectrum. However, the current assessment approaches of the CT x-ray spectrum require costly measurement equipment and complicated operational procedures, and are often limited to the spectrum corresponding to the center of rotation. In order to address these limitations, the authors propose an angle-dependent estimation technique, where the incident spectra across a wide range of angular trajectories can be estimated accurately with only a single phantom and a single axial scan in the absence of the knowledge of the bowtie filter. Methods: Themore » proposed technique uses a uniform cylindrical phantom, made of ultra-high-molecular-weight polyethylene and positioned in an off-centered geometry. The projection data acquired with an axial scan have a twofold purpose. First, they serve as a reflection of the transmission measurements across different angular trajectories. Second, they are used to reconstruct the cross sectional image of the phantom, which is then utilized to compute the intersection length of each transmission measurement. With each CT detector element recording a range of transmission measurements for a single angular trajectory, the spectrum is estimated for that trajectory. A data conditioning procedure is used to combine information from hundreds of collected transmission measurements to accelerate the estimation speed, to reduce noise, and to improve estimation stability. The proposed spectral estimation technique was validated experimentally using a clinical scanner (Somatom Definition Flash, Siemens Healthcare, Germany) with spectra provided by the manufacturer serving as the comparison standard. Results obtained with the proposed technique were compared against those obtained from a second conventional transmission measurement technique with two materials (i.e., Cu and Al). After validation, the proposed technique was applied to measure spectra from the clinical system across a range of angular trajectories [−15°, 15°] and spectrum settings (80, 100, 120, 140 kVp). Results: At 140 kVp, the proposed technique was comparable to the conventional technique in terms of the mean energy difference (MED, −0.29 keV) and the normalized root mean square difference (NRMSD, 0.84%) from the comparison standard compared to 0.64 keV and 1.56%, respectively, with the conventional technique. The average absolute MEDs and NRMSDs across kVp settings and angular trajectories were less than 0.61 keV and 3.41%, respectively, which indicates a high level of estimation accuracy and stability. Conclusions: An angle-dependent estimation technique of CT x-ray spectra from rotational transmission measurements was proposed. Compared with the conventional technique, the proposed method simplifies the measurement procedures and enables incident spectral estimation for a wide range of angular trajectories. The proposed technique is suitable for rigorous research objectives as well as routine clinical quality control procedures.« less
Robotic Assistance for Ultrasound-Guided Prostate Brachytherapy
Fichtinger, Gabor; Fiene, Jonathan P.; Kennedy, Christopher W.; Kronreif, Gernot; Iordachita, Iulian; Song, Danny Y.; Burdette, Everette C.; Kazanzides, Peter
2016-01-01
We present a robotically assisted prostate brachytherapy system and test results in training phantoms and Phase-I clinical trials. The system consists of a transrectal ultrasound (TRUS) and a spatially co-registered robot, fully integrated with an FDA-approved commercial treatment planning system. The salient feature of the system is a small parallel robot affixed to the mounting posts of the template. The robot replaces the template interchangeably, using the same coordinate system. Established clinical hardware, workflow and calibration remain intact. In all phantom experiments, we recorded the first insertion attempt without adjustment. All clinically relevant locations in the prostate were reached. Non-parallel needle trajectories were achieved. The pre-insertion transverse and rotational errors (measured with a Polaris optical tracker relative to the template’s coordinate frame) were 0.25mm (STD=0.17mm) and 0.75° (STD=0.37°). In phantoms, needle tip placement errors measured in TRUS were 1.04mm (STD=0.50mm). A Phase-I clinical feasibility and safety trial has been successfully completed with the system. We encountered needle tip positioning errors of a magnitude greater than 4mm in only 2 out of 179 robotically guided needles, in contrast to manual template guidance where errors of this magnitude are much more common. Further clinical trials are necessary to determine whether the apparent benefits of the robotic assistant will lead to improvements in clinical efficacy and outcomes. PMID:18650122
Saad, F; Ivanescu, C; Phung, D; Loriot, Y; Abhyankar, S; Beer, T M; Tombal, B; Holmstrom, S
2017-03-01
We investigated the impact of skeletal-related events (SREs) on health-related quality of life (HRQoL) in patients with metastatic castration-resistant prostate cancer (mCRPC) in phase III trials of enzalutamide versus placebo. Patients with mCRPC experiencing at least one SRE during AFFIRM and PREVAIL were assessed for trajectory-adjusted mean change in HRQoL by first SRE using Functional Assessment of Cancer Therapy-Prostate (FACT-P; AFFIRM, three domains, and PREVAIL, nine domains) and EQ-5D (PREVAIL) instruments. First SREs caused HRQoL deterioration in both trials. Spinal cord compression had the largest impact, with clinically meaningful reductions in seven of nine FACT-P domains in PREVAIL and all three in AFFIRM (mean (95% confidence interval (CI)) change in FACT-P total score -16.95 (-26.47, -7.44) and -9.69 (-16.10, -3.27), respectively). In PREVAIL, first SREs caused clinically meaningful declines in EQ-5D utility index, irrespective of category; spinal cord compression had the largest impact (mean (95% CI) change -0.24 (-0.39, -0.08)). In AFFIRM, FACT-P and FACT-General total scores showed clinically meaningful declines after radiation/surgery to bone. SREs were associated with clinically meaningful functional declines in the daily lives of patients with mCRPC. Spinal cord compression had the largest impact on HRQoL.
Emeville, Elise; Ferdinand, Séverine; Punga, Augustin; Lufuma, Simon; Blanchet, Pascal; Romana, Marc; Multigner, Luc
2016-01-01
Background Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer. Objective We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry. Methods In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Results The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations. Conclusions These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry. PMID:27074016
Liu, Xin; Tang, Jie; Fei, Xiang; Li, Qiu-Yang
2015-11-01
We aimed to value the usefulness of free to total prostate-specific antigen and Prostate-specific antigen (PSA) density for prostate cancer in the patients with PSA levels of 4.0 ng/ml or less. A total of 343 subjects with PSA levels of 4.0 ng/ml or less were biopsied. All patients were divided into four groups according to the PSA levels: 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml. The reliability of cancer detection in relation to the f/t PSA ratio and PSAD were estimated. Overall, 65 people were diagnosed with prostate cancer. The detection rate was 16.28%、17.17%, 21.82%, 25.00% in subjects with PSA levels of 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml, respectively. The f/t PSA ratio was significantly lower in patients with prostate cancer and PSA levels of 2.1 to 4.0 ng/ml (P<0.05). The PSAD had no statistical significance between the two groups. Routine prostate biopsy should be undertaken if the f/t PSA ratio less than 15% with /without abnormal DRE/TRUS findings.
Suskind, Anne M; Berry, Sandra H; Ewing, Brett A; Elliott, Marc N; Suttorp, Marika J; Clemens, J Quentin
2013-01-01
As part of the RICE (RAND Interstitial Cystitis Epidemiology) study, we developed validated case definitions to identify interstitial cystitis/bladder pain syndrome in women and chronic prostatitis/chronic pelvic pain syndrome in men. Using population based screening methods, we applied these case definitions to determine the prevalence of these conditions in men. A total of 6,072 households were contacted by telephone to screen for men who had symptoms of interstitial cystitis/bladder pain syndrome or chronic prostatitis/chronic pelvic pain syndrome. An initial 296 men screened positive, of whom 149 met the inclusionary criteria and completed the telephone interview. For interstitial cystitis/bladder pain syndrome 2 case definitions were applied (1 with high sensitivity and 1 with high specificity), while for chronic prostatitis/chronic pelvic pain syndrome a single case definition (with high sensitivity and specificity) was used. These case definitions were used to classify subjects into groups based on diagnosis. The interstitial cystitis/bladder pain syndrome weighted prevalence estimates for the high sensitivity and high specificity definitions were 4.2% (3.1-5.3) and 1.9% (1.1-2.7), respectively. The chronic prostatitis/chronic pelvic pain syndrome weighted prevalence estimate was 1.8% (0.9-2.7). These values equate to 1,986,972 (95% CI 966,042-2,996,924) men with chronic prostatitis/chronic pelvic pain syndrome and 2,107,727 (95% CI 1,240,485-2,974,969) men with the high specificity definition of interstitial cystitis/bladder pain syndrome in the United States. The overlap between men who met the high specificity interstitial cystitis/bladder pain syndrome case definition or the chronic prostatitis/chronic pelvic pain syndrome case definition was 17%. Symptoms of interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome are widespread among men in the United States. The prevalence of interstitial cystitis/bladder pain syndrome symptoms in men approaches that in women, suggesting that this condition may be underdiagnosed in the male population. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Improving absolute gravity estimates by the L p -norm approximation of the ballistic trajectory
NASA Astrophysics Data System (ADS)
Nagornyi, V. D.; Svitlov, S.; Araya, A.
2016-04-01
Iteratively re-weighted least squares (IRLS) were used to simulate the L p -norm approximation of the ballistic trajectory in absolute gravimeters. Two iterations of the IRLS delivered sufficient accuracy of the approximation without a significant bias. The simulations were performed on different samplings and perturbations of the trajectory. For the platykurtic distributions of the perturbations, the L p -approximation with 3 < p < 4 was found to yield several times more precise gravity estimates compared to the standard least-squares. The simulation results were confirmed by processing real gravity observations performed at the excessive noise conditions.
SU-E-T-473: A Patient-Specific QC Paradigm Based On Trajectory Log Files and DICOM Plan Files
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeMarco, J; McCloskey, S; Low, D
Purpose: To evaluate a remote QC tool for monitoring treatment machine parameters and treatment workflow. Methods: The Varian TrueBeamTM linear accelerator is a digital machine that records machine axis parameters and MLC leaf positions as a function of delivered monitor unit or control point. This information is saved to a binary trajectory log file for every treatment or imaging field in the patient treatment session. A MATLAB analysis routine was developed to parse the trajectory log files for a given patient, compare the expected versus actual machine and MLC positions as well as perform a cross-comparison with the DICOM-RT planmore » file exported from the treatment planning system. The parsing routine sorts the trajectory log files based on the time and date stamp and generates a sequential report file listing treatment parameters and provides a match relative to the DICOM-RT plan file. Results: The trajectory log parsing-routine was compared against a standard record and verify listing for patients undergoing initial IMRT dosimetry verification and weekly and final chart QC. The complete treatment course was independently verified for 10 patients of varying treatment site and a total of 1267 treatment fields were evaluated including pre-treatment imaging fields where applicable. In the context of IMRT plan verification, eight prostate SBRT plans with 4-arcs per plan were evaluated based on expected versus actual machine axis parameters. The average value for the maximum RMS MLC error was 0.067±0.001mm and 0.066±0.002mm for leaf bank A and B respectively. Conclusion: A real-time QC analysis program was tested using trajectory log files and DICOM-RT plan files. The parsing routine is efficient and able to evaluate all relevant machine axis parameters during a patient treatment course including MLC leaf positions and table positions at time of image acquisition and during treatment.« less
Relationship of urinary isoprostanes to prostate cancer occurrence.
Brys, Magdalena; Morel, Agnieszka; Forma, Ewa; Krzeslak, Anna; Wilkosz, Jacek; Rozanski, Waldemar; Olas, Beata
2013-01-01
To estimate the oxidative stress in patients with prostate cancer and in a control group, we used the biomarker of lipid peroxidation-isoprostanes (8-isoPGF(2)) and the level of selected antioxidants (glucose and uric acid [UA]). The level of urinary isoprostanes was determined in patients and controls using an immunoassay kit according to the manufacturer's instruction. The levels of UA and glucose were also determined in serum by the use of UA Assay Kit and Glucose Assay Kit. We observed a statistically increased the level of isoprostanes in urine of patients with prostate cancer in compared with a control group. The concentration of tested antioxidants in blood from patients with prostate cancer was also higher than in healthy subjects. Moreover, our experiments indicate that the correlation between the increased amount of UA and the lipid peroxidation exists in prostate cancer patients (in all tested groups). Prostate cancer risk by urinary isoprostanes level was analyzed, and a positive association was found (relative risk for highest vs. lowest quartile of urinary isoprostanes = 1.6; 95 % confidence interval 1.2-2.4; p for trend = 0.03). We suggest that reactive oxygen species induce peroxidation of unsaturated fatty acid in patients with prostate cancer, and the level of isoprostanes may be used as a non-invasive marker for determination of oxidative stress. We also propose that UA may enhance the oxidative stress in patients with prostate cancer.
Urine Flow Dynamics Through Prostatic Urethra With Tubular Organ Modeling Using Endoscopic Imagery
Kambara, Yoichi; Yamanishi, Tomonori; Naya, Yukio; Igarashi, Tatsuo
2014-01-01
Voiding dysfunction is common in the aged male population. However, the obstruction mechanism in the lower urinary tract and critical points for obstruction remains uncertain. The aim of this paper was to develop a system to investigate the relationship between voiding dysfunction and alteration of the shape of the prostatic urethra by processing endoscopic video images of the urethra and analyzing the fluid dynamics of the urine stream. A panoramic image of the prostatic urethra was generated from cystourethroscopic video images. A virtual 3-D model of the urethra was constructed using the luminance values in the image. Fluid dynamics using the constructed model was then calculated assuming a static urethra and maximum urine flow rate. Cystourethroscopic videos from 11 patients with benign prostatic hyperplasia were recorded around administration of an alpha-1 adrenoceptor antagonist. The calculated pressure loss through the prostatic urethra in each model corresponded to the prostatic volume, and the improvements of the pressure loss after treatment correlated to the conventional clinical indices. As shown by the proposed method, the shape of the prostatic urethra affects the transporting urine fluid energy, and this paper implies a possible method for detecting critical lesions responsible for voiding dysfunction. The proposed method provides critical information about deformation of the prostatic urethra on voiding function. Detailed differences in the various types of relaxants for the lower urinary tract could be estimated. PMID:27170869
Reentry trajectory optimization based on a multistage pseudospectral method.
Zhao, Jiang; Zhou, Rui; Jin, Xuelian
2014-01-01
Of the many direct numerical methods, the pseudospectral method serves as an effective tool to solve the reentry trajectory optimization for hypersonic vehicles. However, the traditional pseudospectral method is time-consuming due to large number of discretization points. For the purpose of autonomous and adaptive reentry guidance, the research herein presents a multistage trajectory control strategy based on the pseudospectral method, capable of dealing with the unexpected situations in reentry flight. The strategy typically includes two subproblems: the trajectory estimation and trajectory refining. In each processing stage, the proposed method generates a specified range of trajectory with the transition of the flight state. The full glide trajectory consists of several optimal trajectory sequences. The newly focused geographic constraints in actual flight are discussed thereafter. Numerical examples of free-space flight, target transition flight, and threat avoidance flight are used to show the feasible application of multistage pseudospectral method in reentry trajectory optimization.
Reentry Trajectory Optimization Based on a Multistage Pseudospectral Method
Zhou, Rui; Jin, Xuelian
2014-01-01
Of the many direct numerical methods, the pseudospectral method serves as an effective tool to solve the reentry trajectory optimization for hypersonic vehicles. However, the traditional pseudospectral method is time-consuming due to large number of discretization points. For the purpose of autonomous and adaptive reentry guidance, the research herein presents a multistage trajectory control strategy based on the pseudospectral method, capable of dealing with the unexpected situations in reentry flight. The strategy typically includes two subproblems: the trajectory estimation and trajectory refining. In each processing stage, the proposed method generates a specified range of trajectory with the transition of the flight state. The full glide trajectory consists of several optimal trajectory sequences. The newly focused geographic constraints in actual flight are discussed thereafter. Numerical examples of free-space flight, target transition flight, and threat avoidance flight are used to show the feasible application of multistage pseudospectral method in reentry trajectory optimization. PMID:24574929
Maximum likelihood-based analysis of single-molecule photon arrival trajectories.
Hajdziona, Marta; Molski, Andrzej
2011-02-07
In this work we explore the statistical properties of the maximum likelihood-based analysis of one-color photon arrival trajectories. This approach does not involve binning and, therefore, all of the information contained in an observed photon strajectory is used. We study the accuracy and precision of parameter estimates and the efficiency of the Akaike information criterion and the Bayesian information criterion (BIC) in selecting the true kinetic model. We focus on the low excitation regime where photon trajectories can be modeled as realizations of Markov modulated Poisson processes. The number of observed photons is the key parameter in determining model selection and parameter estimation. For example, the BIC can select the true three-state model from competing two-, three-, and four-state kinetic models even for relatively short trajectories made up of 2 × 10(3) photons. When the intensity levels are well-separated and 10(4) photons are observed, the two-state model parameters can be estimated with about 10% precision and those for a three-state model with about 20% precision.
NASA Astrophysics Data System (ADS)
Matsunaga, Y.; Sugita, Y.
2018-06-01
A data-driven modeling scheme is proposed for conformational dynamics of biomolecules based on molecular dynamics (MD) simulations and experimental measurements. In this scheme, an initial Markov State Model (MSM) is constructed from MD simulation trajectories, and then, the MSM parameters are refined using experimental measurements through machine learning techniques. The second step can reduce the bias of MD simulation results due to inaccurate force-field parameters. Either time-series trajectories or ensemble-averaged data are available as a training data set in the scheme. Using a coarse-grained model of a dye-labeled polyproline-20, we compare the performance of machine learning estimations from the two types of training data sets. Machine learning from time-series data could provide the equilibrium populations of conformational states as well as their transition probabilities. It estimates hidden conformational states in more robust ways compared to that from ensemble-averaged data although there are limitations in estimating the transition probabilities between minor states. We discuss how to use the machine learning scheme for various experimental measurements including single-molecule time-series trajectories.
Cognitive Trajectory Changes Over 20 Years Before Dementia Diagnosis: A Large Cohort Study.
Li, Ge; Larson, Eric B; Shofer, Jane B; Crane, Paul K; Gibbons, Laura E; McCormick, Wayne; Bowen, James D; Thompson, Mary Lou
2017-12-01
Longitudinal studies have shown an increase in cognitive decline many years before clinical diagnosis of dementia. We sought to estimate changes, relative to "normal" aging, in the trajectory of scores on a global cognitive function test-the Cognitive Abilities Screening Instrument (CASI). A prospective cohort study. Community-dwelling members of a U.S. health maintenance organization. Individuals aged 65 and older who had no dementia diagnosis at baseline and had at least two visits with valid CASI test score (N = 4,315). Average longitudinal trajectories, including changes in trajectory before clinical diagnosis in those who would be diagnosed with dementia, were estimated for CASI item response theory (IRT) scores. The impact of sex, education level, and APOE genotype on cognitive trajectories was assessed. Increased cognitive decline relative to "normal" aging was evident in CASI IRT at least 10 years before clinical diagnosis. Male gender, lower education, and presence of ≥1 APOE ε4 alleles were associated with lower average IRT scores. In those who would be diagnosed with dementia, a trajectory change point was estimated at an average of 3.1 years (95% confidence interval 3.0-3.2) before clinical diagnosis, after which cognitive decline appeared to accelerate. The change point did not differ by sex, education level, or APOE ε4 genotype. There were subtle differences in trajectory slopes by sex and APOE ε4 genotype, but not by education. Decline in average global cognitive function was evident at least 10 years before clinical diagnosis of dementia. The decline accelerated about 3 years before clinical diagnosis. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.
Wang, Kai; Li, Yao; Teng, Jing-Fei; Zhou, Hai-Yong; Xu, Dan-Feng; Fan, Yi
2015-01-01
To evaluate the efficacy and safety of plasmakinetic resection of the prostate (PKRP) versus transurethral resection of the prostate (TURP) for the treatment of patients with benign prostate hyperplasia (BPH), a meta-analysis of randomized controlled trials was carried out. We searched PubMed, Embase, Web of Science and the Cochrane Library. The pooled estimates of maximum flow rate, International Prostate Symptom Score, operation time, catheterization time, irrigated volume, hospital stay, transurethral resection syndrome, transfusion, clot retention, urinary retention and urinary stricture were assessed. There was no notable difference in International Prostate Symptom Score between TURP and PKRP groups during the 1-month, 3 months, 6 months and 12 months follow-up period, while the pooled Q max at 1-month favored PKRP group. PKRP group was related to a lower risk rate of transurethral resection syndrome, transfusion and clot retention, and the catheterization time and operation time were also shorter than that of TURP. The irrigated volume, length of hospital stay, urinary retention and urinary stricture rate were similar between groups. In conclusion, our study suggests that the PKRP is a reliable minimal invasive technique and may anticipatorily prove to be an alternative electrosurgical procedure for the treatment of BPH.
Ciatto, Stefano; Bonardi, Rita; Lombardi, Claudio; Zappa, Marco; Gervasi, Ginetta
2002-01-01
To evaluate the sensitivity at transrectal ultrasonography (TRUS) for prostate cancer. A consecutive series of 170 prostate cancers identified by matching local cancer registry and TRUS archives at the Centro per lo Studio e la Prevenzione Oncologica of Florence. TRUS sensitivity was determined as the ratio of TRUS positive to total prostate cancers occurring at different intervals from TRUS date. Univariate and multivariate analyses of sensitivity determinants were performed. Sensitivity at 6 months, 1, 2 and 3 years after the test was 94.1% (95% CI, 90-98), 89.8% (95% CI, 85-95), 80.4% (95% CI, 74-87) and 74.1% (95% CI, 68-81%), respectively. A higher sensitivity (statistically significant) of TRUS was observed only if digital rectal examination was suspicious, whereas no association to sensitivity was observed for age, prostate-specific antigen or prostate-specific antigen density. The study provided a reliable estimate of TRUS sensitivity, particularly reliable being checked against a cancer registry: observed sensitivity was high, at least of the same magnitude of other cancer screening tests. TRUS, which is known to allow for considerable diagnostic anticipation and is more specific than prostate-specific antigen, might still be considered for its contribution to a screening approach.
Deep Learning Role in Early Diagnosis of Prostate Cancer
Reda, Islam; Khalil, Ashraf; Elmogy, Mohammed; Abou El-Fetouh, Ahmed; Shalaby, Ahmed; Abou El-Ghar, Mohamed; Elmaghraby, Adel; Ghazal, Mohammed; El-Baz, Ayman
2018-01-01
The objective of this work is to develop a computer-aided diagnostic system for early diagnosis of prostate cancer. The presented system integrates both clinical biomarkers (prostate-specific antigen) and extracted features from diffusion-weighted magnetic resonance imaging collected at multiple b values. The presented system performs 3 major processing steps. First, prostate delineation using a hybrid approach that combines a level-set model with nonnegative matrix factorization. Second, estimation and normalization of diffusion parameters, which are the apparent diffusion coefficients of the delineated prostate volumes at different b values followed by refinement of those apparent diffusion coefficients using a generalized Gaussian Markov random field model. Then, construction of the cumulative distribution functions of the processed apparent diffusion coefficients at multiple b values. In parallel, a K-nearest neighbor classifier is employed to transform the prostate-specific antigen results into diagnostic probabilities. Finally, those prostate-specific antigen–based probabilities are integrated with the initial diagnostic probabilities obtained using stacked nonnegativity constraint sparse autoencoders that employ apparent diffusion coefficient–cumulative distribution functions for better diagnostic accuracy. Experiments conducted on 18 diffusion-weighted magnetic resonance imaging data sets achieved 94.4% diagnosis accuracy (sensitivity = 88.9% and specificity = 100%), which indicate the promising results of the presented computer-aided diagnostic system. PMID:29804518
Contemporary treatment options for chronic prostatitis/chronic pelvic pain syndrome.
Ismail, M; Mackenzie, K; Hashim, H
2013-07-01
The prostate gland, about the size a walnut, forms part of the male reproductive system and sits directly underneath the bladder surrounding the urethra. It is a fibromuscular exocrine gland that secretes a complex proteolytic fluid which constitutes one-third of the volume of the seminal fluid. Prostatitis refers to a group of disorders that affect the prostate and cause genitourinary pain, dysuria, urinary frequency and sexual dysfunction. The prevalence of prostatitis in the United States has been estimated to be around 9%, while the worldwide prevalence ranges from 2 to 10%, and 15% of men experience prostatitis-like symptoms at some point in their lives. There are a number of treatments which have been used for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), with only a small amount of high-level evidence. The current recommended treatment for CP/CPPS is predominantly a multimodal approach using a combination of antibiotics, α-blockers, antimuscarinic and anti-inflammatory drugs. The response to treatment and improvement in symptoms is very variable; therefore, as the evidence evolves, it is likely that treatment will become symptom specific rather than a generic, 'one strategy fits all' treatment for CP/CPPS. Copyright 2013 Prous Science, S.A.U. or its licensors. All rights reserved.
Development of a 6DOF robotic motion phantom for radiation therapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Belcher, Andrew H.; Liu, Xinmin; Grelewicz, Zachary
Purpose: The use of medical technology capable of tracking patient motion or positioning patients along 6 degree-of-freedom (6DOF) has steadily increased in the field of radiation therapy. However, due to the complex nature of tracking and performing 6DOF motion, it is critical that such technology is properly verified to be operating within specifications in order to ensure patient safety. In this study, a robotic motion phantom is presented that can be programmed to perform highly accurate motion along any X (left–right), Y (superior–inferior), Z (anterior–posterior), pitch (around X), roll (around Y), and yaw (around Z) axes. In addition, highly synchronizedmore » motion along all axes can be performed in order to simulate the dynamic motion of a tumor in 6D. The accuracy and reproducibility of this 6D motion were characterized. Methods: An in-house designed and built 6D robotic motion phantom was constructed following the Stewart–Gough parallel kinematics platform archetype. The device was controlled using an inverse kinematics formulation, and precise movements in all 6 degrees-of-freedom (X, Y, Z, pitch, roll, and yaw) were performed, both simultaneously and separately for each degree-of-freedom. Additionally, previously recorded 6D cranial and prostate motions were effectively executed. The robotic phantom movements were verified using a 15 fps 6D infrared marker tracking system and the measured trajectories were compared quantitatively to the intended input trajectories. The workspace, maximum 6D velocity, backlash, and weight load capabilities of the system were also established. Results: Evaluation of the 6D platform demonstrated translational root mean square error (RMSE) values of 0.14, 0.22, and 0.08 mm over 20 mm in X and Y and 10 mm in Z, respectively, and rotational RMSE values of 0.16°, 0.06°, and 0.08° over 10° of pitch, roll, and yaw, respectively. The robotic stage also effectively performed controlled 6D motions, as well as reproduced cranial trajectories over 15 min, with a maximal RMSE of 0.04 mm translationally and 0.04° rotationally, and a prostate trajectory over 2 min, with a maximal RMSE of 0.06 mm translationally and 0.04° rotationally. Conclusions: This 6D robotic phantom has proven to be accurate under clinical standards and capable of reproducing tumor motion in 6D. Such functionality makes the robotic phantom usable for either quality assurance or research purposes.« less
Goddard trajectory determination subsystem: Mathematical specifications
NASA Technical Reports Server (NTRS)
Wagner, W. E. (Editor); Velez, C. E. (Editor)
1972-01-01
The mathematical specifications of the Goddard trajectory determination subsystem of the flight dynamics system are presented. These specifications include the mathematical description of the coordinate systems, dynamic and measurement model, numerical integration techniques, and statistical estimation concepts.
A genome-wide pleiotropy scan for prostate cancer risk.
Panagiotou, Orestis A; Travis, Ruth C; Campa, Daniele; Berndt, Sonja I; Lindstrom, Sara; Kraft, Peter; Schumacher, Fredrick R; Siddiq, Afshan; Papatheodorou, Stefania I; Stanford, Janet L; Albanes, Demetrius; Virtamo, Jarmo; Weinstein, Stephanie J; Diver, W Ryan; Gapstur, Susan M; Stevens, Victoria L; Boeing, Heiner; Bueno-de-Mesquita, H Bas; Barricarte Gurrea, Aurelio; Kaaks, Rudolf; Khaw, Kay-Tee; Krogh, Vittorio; Overvad, Kim; Riboli, Elio; Trichopoulos, Dimitrios; Giovannucci, Edward; Stampfer, Meir; Haiman, Christopher; Henderson, Brian; Le Marchand, Loic; Gaziano, J Michael; Hunter, David J; Koutros, Stella; Yeager, Meredith; Hoover, Robert N; Chanock, Stephen J; Wacholder, Sholom; Key, Timothy J; Tsilidis, Konstantinos K
2015-04-01
No single-nucleotide polymorphisms (SNPs) specific for aggressive prostate cancer have been identified in genome-wide association studies (GWAS). To test if SNPs associated with other traits may also affect the risk of aggressive prostate cancer. SNPs implicated in any phenotype other than prostate cancer (p≤10(-7)) were identified through the catalog of published GWAS and tested in 2891 aggressive prostate cancer cases and 4592 controls from the Breast and Prostate Cancer Cohort Consortium (BPC3). The 40 most significant SNPs were followed up in 4872 aggressive prostate cancer cases and 24,534 controls from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. Odds ratios (ORs) and 95% confidence intervals (CIs) for aggressive prostate cancer were estimated. A total of 4666 SNPs were evaluated by the BPC3. Two signals were seen in regions already reported for prostate cancer risk. rs7014346 at 8q24.21 was marginally associated with aggressive prostate cancer in the BPC3 trial (p=1.6×10(-6)), whereas after meta-analysis by PRACTICAL the summary OR was 1.21 (95% CI 1.16-1.27; p=3.22×10(-18)). rs9900242 at 17q24.3 was also marginally associated with aggressive disease in the meta-analysis (OR 0.90, 95% CI 0.86-0.94; p=2.5×10(-6)). Neither of these SNPs remained statistically significant when conditioning on correlated known prostate cancer SNPs. The meta-analysis by BPC3 and PRACTICAL identified a third promising signal, marked by rs16844874 at 2q34, independent of known prostate cancer loci (OR 1.12, 95% CI 1.06-1.19; p=4.67×10(-5)); it has been shown that SNPs correlated with this signal affect glycine concentrations. The main limitation is the heterogeneity in the definition of aggressive prostate cancer between BPC3 and PRACTICAL. We did not identify new SNPs for aggressive prostate cancer. However, rs16844874 may provide preliminary genetic evidence on the role of the glycine pathway in prostate cancer etiology. We evaluated whether genetic variants associated with several traits are linked to the risk of aggressive prostate cancer. No new such variants were identified. Copyright © 2014 European Association of Urology. All rights reserved.
Habib, Ashraf S; Moul, Judd W; Polascik, Thomas J; Robertson, Cary N; Roche, Anthony M; White, William D; Hill, Stephen E; Nosnick, Israel; Gan, Tong J
2014-05-01
To compare acute normovolemic hemodilution versus low central venous pressure strategy versus conventional fluid management in reducing intraoperative estimated blood loss, hematocrit drop and need for blood transfusion in patients undergoing radical retropubic prostatectomy under general anesthesia. Patients undergoing radical retropubic prostatectomy under general anesthesia were randomized to conventional fluid management, acute normovolemic hemodilution or low central venous pressure (≤5 mmHg). Treatment effects on estimated blood loss and hematocrit change were tested in multivariable regression models accounting for surgeon, prostate size, and all two-way interactions. Ninety-two patients completed the study. Estimated blood loss (mean ± SD) was significantly lower with low central venous pressure (706 ± 362 ml) compared to acute normovolemic hemodilution (1103 ± 635 ml) and conventional (1051 ± 714 ml) groups (p = 0.0134). There was no difference between the groups in need for blood transfusion, or hematocrit drop from preoperative values. The multivariate model predicting estimated blood loss showed a significant effect of treatment (p = 0.0028) and prostate size (p = 0.0323), accounting for surgeon (p = 0.0013). In the model predicting hematocrit change, accounting for surgeon difference (p = 0.0037), the treatment effect depended on prostate size (p = 0.0007) with the slope of low central venous pressure differing from the other two groups. Hematocrit was predicted to drop more with increased prostate size in acute normovolemic hemodilution and conventional groups but not with low central venous pressure. Limitations include the inability to blind providers to group assignment, possible variability between providers in estimation of blood loss, and the relatively small sample size that was not powered to detect differences between the groups in need for blood transfusion. Maintaining low central venous pressure reduced estimated blood loss compared to conventional fluid management and acute normovolemic hemodilution in patients undergoing radical retropubic prostatectomy but there was no difference in allogeneic blood transfusion between the groups.
Body mass trajectories, diabetes mellitus, and mortality in a large cohort of Austrian adults.
Peter, Raphael Simon; Keller, Ferdinand; Klenk, Jochen; Concin, Hans; Nagel, Gabriele
2016-12-01
There are only few studies on latent trajectories of body mass index (BMI) and their association with diabetes incidence and mortality in adults.We used data of the Vorarlberg Health Monitoring & Prevention Program and included individuals (N=24,875) with BMI measurements over a 12-year period. Trajectory classes were identified using growth mixture modeling for predefined age groups (<50, 50-65, >65 years of age) and men, women separately. Poisson models were applied to estimate incidence and prevalence of diabetes for each trajectory class. Relative all-cause mortality and diabetes-related mortality was estimated using Cox proportional hazard regression.We identified 4 trajectory classes for the age groups <50 years and 50 to 65 years, and 3 for age groups >65 years. For all age groups, a stable BMI trajectory class was the largest, with about 90% of men and 70% to 80% of women. For the low stable BMI classes, the corresponding fasting glucose levels were the lowest. The highest diabetes prevalences were observed for decreasing trajectories. During subsequent follow-up of mean 8.1 (SD 2.0) years, 2741 individuals died. For men <50 years, highest mortality was observed for steady weight gainers. For all other age-sex groups, mortality was the highest for decreasing trajectories.We found considerably heterogeneity in BMI trajectories by sex and age. Stable weight, however, was the largest class over all age and sex groups, and was associated with the lowest diabetes incidence and mortality suggesting that maintaining weight at a moderate level is an important public health goal.
Schalk, Stefan G; Demi, Libertario; Smeenge, Martijn; Mills, David M; Wallace, Kirk D; de la Rosette, Jean J M C H; Wijkstra, Hessel; Mischi, Massimo
2015-05-01
Currently, nonradical treatment for prostate cancer is hampered by the lack of reliable diagnostics. Contrastultrasound dispersion imaging (CUDI) has recently shown great potential as a prostate cancer imaging technique. CUDI estimates the local dispersion of intravenously injected contrast agents, imaged by transrectal dynamic contrast-enhanced ultrasound (DCE-US), to detect angiogenic processes related to tumor growth. The best CUDI results have so far been obtained by similarity analysis of the contrast kinetics in neighboring pixels. To date, CUDI has been investigated in 2-D only. In this paper, an implementation of 3-D CUDI based on spatiotemporal similarity analysis of 4-D DCE-US is described. Different from 2-D methods, 3-D CUDI permits analysis of the entire prostate using a single injection of contrast agent. To perform 3-D CUDI, a new strategy was designed to estimate the similarity in the contrast kinetics at each voxel, and data processing steps were adjusted to the characteristics of 4-D DCE-US images. The technical feasibility of 4-D DCE-US in 3-D CUDI was assessed and confirmed. Additionally, in a preliminary validation in two patients, dispersion maps by 3-D CUDI were quantitatively compared with those by 2-D CUDI and with 12-core systematic biopsies with promising results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lo, Andrea C.; Morris, W. James, E-mail: JMorris@bccancer.bc.ca; Pickles, Tom
Objectives: This study examined patterns of recurrence after low–dose-rate prostate brachytherapy (LDR-PB), estimated local recurrence rate and compared that rate to the estimated local recurrence rate after radical prostatectomy (RP). Methods and Materials: A prospective database was maintained with clinical, dosimetric, and outcome data for all LDR-PB implantation procedures performed at our institution. From 1998 to 2008, 2223 patients with prostate cancer received LDR-PB without supplemental external beam radiation therapy. Patients who developed Phoenix-defined biochemical failure were reviewed for sites of relapse and investigations completed. Results: At a median follow-up of 5 years, 108 of 2223 patients (4.8%) developed biochemical relapse.more » In 1 additional patient, local relapse was found on transurethral prostate resection, but his prostate-specific antigen concentration was well short of triggering Phoenix-defined failure. Of the 109 patients with disease relapse, 18 of 2223 (0.8%) had a proven local recurrence, and 30 of 2223 (1.3%) had a proven distant recurrence. The remaining 61 of 2223 patients (2.7%) had unidentified sites of recurrence; of these, 57 patients (93%) had digital rectal examinations (DREs), 18 (30%) had post-treatment biopsies, 45 (74%) had bone scans, and 34 (56%) had computed tomography imaging of the abdomen and pelvis. If every biochemical failure were local, the local recurrence rate would be as high as 4.9%; however, by excluding those with proven distant failure and those with both a negative DRE and biopsy, we estimate that the local recurrence rate is 2.7% or less. Conclusions: In the context of limitations of the study design, our population-based analysis indicates that the local recurrence rate after LDR-PB is as low or lower than that after RP in our jurisdiction.« less
Dall'Era, Marc A; Lo, Mary J; Chen, Jaclyn; Cress, Rosemary; Hamilton, Ann S
2018-05-01
To the authors' knowledge, the survival benefit of local therapy in the setting of advanced prostate cancer remains unknown. The authors investigated whether prostate-directed treatment with either surgery or radiotherapy versus conservative treatment in the setting of locally advanced or metastatic disease was associated with improved survival within a cohort of men from the Centers for Disease Control and Prevention's (CDC) Breast and Prostate Cancer Data Quality and Patterns of Care Study (CDC POC-BP). Men diagnosed with locally advanced (cT3-T4 or N+ and M0) or metastatic prostate cancer were identified. The authors compared survival by treatment type, categorized as conservative (androgen deprivation therapy only) versus aggressive (radical prostatectomy or any type of radiotherapy). Nine-year overall survival and prostate cancer-specific survival were estimated using the Kaplan-Meier method. The Cox proportional hazards model was used to determine factors independently associated with 9-year prostate cancer-specific survival. For men with advanced, nonmetastatic prostate cancer, conservative treatment alone was associated with a 4 times higher likelihood of prostate cancer mortality compared with men treated with surgery (hazard ratio, 4.18; 95% confidence interval, 1.44-12.14). In contrast, no difference was found between conservative versus aggressive treatment after adjusting for covariates for men with metastatic disease. The 9-year prostate cancer-specific survival rate was 27% for those receiving aggressive treatment versus 24% for men undergoing conservative treatment. The authors did not observe a survival advantage with local therapy in addition to standard androgen deprivation therapy for men with metastatic prostate cancer. However, the results of the current study did affirm advantages in the setting of locally advanced disease. Aggressive local therapy in the setting of metastatic disease needs to be studied carefully before clinical adoption. Cancer 2018;124:1921-8. © 2018 American Cancer Society. © 2018 American Cancer Society.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, D; Usmani, N; Sloboda, R
Purpose: To characterize the movement of implanted brachytherapy seeds due to transrectal ultrasound probe-induced prostate deformation and to estimate the effects on prostate dosimetry. Methods: Implanted probe-in and probe-removed seed distributions were reconstructed for 10 patients using C-arm fluoroscopy imaging. The prostate was delineated on ultrasound and registered to the fluoroscopy seeds using a visible subset of seeds and residual needle tracks. A linear tensor and shearing model correlated the seed movement with position. The seed movement model was used to infer the underlying prostate deformation and to simulate the prostate contour without probe compression. Changes in prostate and surrogatemore » urethra dosimetry were calculated. Results: Seed movement patterns reflecting elastic decompression, lateral shearing, and rectal bending were observed. Elastic decompression was characterized by anterior-posterior expansion and superior-inferior and lateral contractions. For lateral shearing, anterior movement up to 6 mm was observed for extraprostatic seeds in the lateral peripheral region. The average intra-prostatic seed movement was 1.3 mm, and the residual after linear modeling was 0.6 mm. Prostate D90 increased by 4 Gy on average (8 Gy max) and was correlated with elastic decompression. For selected patients, lateral shearing resulted in differential change in D90 of 7 Gy between anterior and posterior quadrants, and increase in whole prostate D90 of 4 Gy. Urethra D10 increased by 4 Gy. Conclusion: Seed movement upon probe removal was characterized. The proposed model captured the linear correlation between seed movement and position. Whole prostate dose coverage increased slightly, due to the small but systematic seed movement associated with elastic decompression. Lateral shearing movement increased dose coverage in the anterior-lateral region, at the expense of the posterior-lateral region. The effect on whole prostate D90 was smaller due to the subset of peripheral seeds involved, but lateral shearing movement can have greater consequences for local dose coverage.« less
Bhadra, Dhiman; Daniels, Michael J.; Kim, Sungduk; Ghosh, Malay; Mukherjee, Bhramar
2014-01-01
In a typical case-control study, exposure information is collected at a single time-point for the cases and controls. However, case-control studies are often embedded in existing cohort studies containing a wealth of longitudinal exposure history on the participants. Recent medical studies have indicated that incorporating past exposure history, or a constructed summary measure of cumulative exposure derived from the past exposure history, when available, may lead to more precise and clinically meaningful estimates of the disease risk. In this paper, we propose a flexible Bayesian semiparametric approach to model the longitudinal exposure profiles of the cases and controls and then use measures of cumulative exposure based on a weighted integral of this trajectory in the final disease risk model. The estimation is done via a joint likelihood. In the construction of the cumulative exposure summary, we introduce an influence function, a smooth function of time to characterize the association pattern of the exposure profile on the disease status with different time windows potentially having differential influence/weights. This enables us to analyze how the present disease status of a subject is influenced by his/her past exposure history conditional on the current ones. The joint likelihood formulation allows us to properly account for uncertainties associated with both stages of the estimation process in an integrated manner. Analysis is carried out in a hierarchical Bayesian framework using Reversible jump Markov chain Monte Carlo (RJMCMC) algorithms. The proposed methodology is motivated by, and applied to a case-control study of prostate cancer where longitudinal biomarker information is available for the cases and controls. PMID:22313248
Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study.
Lynch, Brigid M; Friedenreich, Christine M; Kopciuk, Karen A; Hollenbeck, Albert R; Moore, Steven C; Matthews, Charles E
2014-05-01
Sedentary behavior (sitting time) has been proposed as an independent risk factor for some cancers; however, its role in the development of prostate cancer has not been determined. We examined the prospective associations of self-reported daily sitting time and daily television/video viewing time with the risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated HRs and 95% confidence intervals (CI) using Cox proportional hazards regression. Between 1996 and 2006, there were 13,751 incident (including 1,365 advanced) prostate cancer cases identified; prostate cancer mortality (through 2008) was 669. No strong or significant association with prostate cancer risk was seen in fully adjusted models for either daily sitting or television/video time. There were some suggestions of effect modification by body mass index (BMI; interaction for television/video time and BMI, P = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but nonsignificant, increase amongst obese men (HR = 1.28; 95% CI, 0.98-1.69); a null association was observed amongst overweight men (HR = 1.04; 0.89-1.22); and, for men with a normal BMI, television/video time was associated with a nonsignificant risk decrease (HR = 0.82; 95% CI, 0.66-1.01). Similar patterns were observed for total daily sitting and television/video time in advanced prostate cancer and prostate cancer mortality. Sedentary behavior seems to play a limited role in the development of prostate cancer; however, we cannot rule out potential effect modification by BMI or the impact of measurement error on results. ©2014 AACR.
Robot-assisted laparoscopic prostatectomy for a giant prostate with retrieval of vesical stones.
Singh, Iqbal; Hudson, Jon E; Hemal, Ashok K
2010-09-01
To report and describe the technique of robot assisted prostatectomy (RAP) and retrieval of vesical stones. We describe the technique of RAP and retrieval of vesical stones under endoscopic guidance. The relevant published English literature (Pub Med™) was also searched for giant enlargement of prostate glands in order to ascertain their management. An elderly, male with a BMI of 32.49, clinically diagnosed as a case of giant BPH (prior negative prostate biopsy) with vesical stones and severe LUTS, was successfully managed by modified robot assisted laparoscopic technique of prostatectomy with removal of bladder stones. The specimen weighed 384 g. The total ORT, estimated blood loss and hospital stay was 300 min, 600 cc and 3 days, respectively. The final histology was predominant BPH with an incidental focal adenocarcinoma within the distal left prostate. The patient is continent and doing fine at a follow up of 12 months with the serum PSA < 0.006 ng/ml. Giant prostatic enlargement is an uncommonly reported entity. Minimally invasive management of massively enlarged prostate with associated bladder stones is a challenging task. Traditionally such patients have been managed with open surgery. The present case of giant prostate enlargement (incidental localized prostate cancer) with vesical stones was successfully managed by a combination of robotic prostatectomy and removal of bladder stones under flexible endoscopic guidance. The technical problems and nuances associated with the technique of robotic assisted prostatectomy (RAP) for giant prostate enlargement have been discussed. To the best of our knowledge the present case is the largest (384 g) reported case of cancer prostate (concomitant vesical stone), to be removed by minimally invasive robot assisted laparoscopic technique in the English literature (PubMed™).
Tang, Li; Yao, Song; Till, Cathee; Goodman, Phyllis J.; Tangen, Catherine M.; Wu, Yue; Kristal, Alan R.; Platz, Elizabeth A.; Neuhouser, Marian L.; Stanczyk, Frank Z.; Reichardt, Juergen K.V.; Santella, Regina M.; Hsing, Ann; Hoque, Ashraful; Lippman, Scott M.; Thompson, Ian M.; Ambrosone, Christine B.
2011-01-01
The etiology of prostate cancer remains elusive, although steroid hormones probably play a role. Considering the carcinogenic potential of estrogen metabolites as well as altered intraprostatic estrogen biosynthesis during the development of prostate cancer, we investigated associations between repeat polymorphisms of three key estrogen-related genes (CYP11A1, CYP19A1, UGT1A1) and risk of prostate cancer in the Prostate Cancer Prevention Trial (PCPT), designed to test finasteride versus placebo as a chemoprevention agent. Using data and specimens from 1154 cases and 1351 controls who were frequency matched on age, family history of prostate cancer and PCPT treatment arm, we used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) separately in the placebo and finasteride arms. Among men in the placebo arm, CYP19A1 7/8 genotype carriers had a significantly higher risk of prostate cancer compared with those with the 7/7 genotype (OR = 1.70, 95% CI = 1.16–2.5), regardless of Gleason grade. This genotype was also associated with elevated serum estrogen levels. For the (TA)n repeat polymorphism in UGT1A1, the heterozygous short (<7 repeats)/long (≥7 repeats) genotype was significantly associated with the risk of low-grade prostate cancer (OR = 1.34, 95% CI = 1.05–1.70) compared with the short/short genotype. No significant association was found with CYP11A1. These associations were not observed among men in the finasteride arm. The results indicate that repeat polymorphisms in genes involved in estrogen biosynthesis and metabolism may influence risk of prostate cancer but that their effects may be modified by factors altering hormone metabolism, such as finasteride treatment. PMID:21771722
Vicari, Enzo; La Vignera, Sandro; Arcoria, Domenico; Condorelli, Rosita; Vicari, Lucia O.; Castiglione, Roberto; Mangiameli, Andrea; Calogero, Aldo E.
2011-01-01
Background Although prostatitis syndrome (PS) and irritable bowel syndrome (IBS) are common disorders, information on the prevalence of IBS in infertile patients with PS is relatively scanty. Therefore, this study was undertaken to estimate the frequency of PS and IBS and to evaluate the prevalence of the various diagnostic categories of prostatitis. Methodology/Principal Findings This study enrolled 152 patients with PS, diagnosed by the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) in an andrological setting, and 204 patients with IBS, diagnosed according to the Rome III diagnostic criteria in a gastroenterological setting. The patients with PS were asked to fulfill the Rome III questionnaire for IBS, whereas patients with IBS were asked to complete the NIH-CPSI. The simultaneous presence of PS and IBS was observed in 30.2% and 31.8% of the patients screened by andrologists and gastroenterologists, respectively. Altogether, 111 patients had PS plus IBS (31.2%). They had a total NIH-CPSI and pain subscale scores significantly higher than patients with PS alone. Gastrointestinal symptoms in patients with PS plus IBS were similar to those reported by patients with IBS alone and significantly greater in patients with PS alone. Patients with PS plus IBS had a significantly higher frequency of chronic bacterial prostatitis (category II) and lower of non-inflammatory prostatitis (category IIIB), compared to patients with PS alone. The frequency of inflammatory prostatitis (category IIIA) resulted similar. Conclusions/Significance Prostatitis syndromes and IBS are frequently associated in patients with PS- or IBS-related symptoms. These patients have an increased prevalence of chronic bacterial and non-inflammatory prostatitis. PMID:21494624
Travis, Ruth C.; Appleby, Paul N.; Tsilidis, Konstantinos K.; Tjønneland, Anne; Olsen, Anja; Overvad, Kim; Katzke, Verena; Kühn, Tilman; Trichopoulou, Antonia; Peppa, Eleni; Kritikou, Maria; Sieri, Sabina; Palli, Domenico; Sacerdote, Carlotta; Tumino, Rosario; Bueno‐de‐Mesquita, H. B(as); Agudo, Antonio; Larrañaga, Nerea; Molina‐Portillo, Elena; Ardanaz, Eva; Chirlaque, Maria‐Dolores; Lasheras, Cristina; Stattin, Pär; Wennberg, Maria; Drake, Isabel; Malm, Johan; Schmidt, Julie A.; Khaw, Kay‐Tee; Gunter, Marc; Freisling, Heinz; Huybrechts, Inge; Aune, Dagfinn; Cross, Amanda J; Riboli, Elio; Key, Timothy J.
2017-01-01
Several dietary factors have been studied in relation to prostate cancer; however, most studies have not reported on subtypes of fruit and vegetables or tumor characteristics, and results obtained so far are inconclusive. This study aimed to examine the prospective association of total and subtypes of fruit and vegetable intake with the incidence of prostate cancer overall, by grade and stage of disease, and prostate cancer death. Lifestyle information for 142,239 men participating in the European Prospective Investigation into Cancer and Nutrition from 8 European countries was collected at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). After an average follow‐up time of 13.9 years, 7,036 prostate cancer cases were identified. Compared with the lowest fifth, those in the highest fifth of total fruit intake had a significantly reduced prostate cancer risk (HR = 0.91; 95% CI = 0.83–0.99; p‐trend = 0.01). No associations between fruit subtypes and prostate cancer risk were observed, except for citrus fruits, where a significant trend was found (HR = 0.94; 95% CI = 0.86–1.02; p‐trend = 0.01). No associations between total and subtypes of vegetables and prostate cancer risk were observed. We found no evidence of heterogeneity in these associations by tumor grade and stage, with the exception of significant heterogeneity by tumor grade (p heterogeneity<0.001) for leafy vegetables. No significant associations with prostate cancer death were observed. The main finding of this prospective study was that a higher fruit intake was associated with a small reduction in prostate cancer risk. Whether this association is causal remains unclear. PMID:28419475
Sedentary behavior and prostate cancer risk in the NIH-AARP Diet and Health Study
Lynch, Brigid M.; Friedenreich, Christine M.; Kopciuk, Karen A.; Hollenbeck, Albert R.; Moore, Steven C.; Matthews, Charles E.
2014-01-01
Sedentary behavior (sitting time) has been proposed as an independent risk factor for some cancers; however, its role in the development of prostate cancer has not been determined. We examined the prospective associations of self-reported daily sitting time and daily television/video viewing time with risk of developing or dying from prostate cancer among 170,481 men in the NIH-AARP Diet and Health Study. We estimated hazard ratios and 95% confidence intervals using Cox Proportional Hazards regression. Between 1996 and 2006 there were 13,751 incident (including 1,365 advanced) prostate cancer cases identified; prostate cancer mortality (through 2008) was 669. No strong or significant association with prostate cancer risk was seen in fully adjusted models for either daily sitting or television/video time. There was some suggestion of effect modification by body mass index (interaction for television/video time and body mass index, p = 0.02). For total prostate cancer risk, television/video time was associated with a slightly elevated, but non-significant increased amongst obese men (HR=1.28, 95%CI: 0.98, 1.69); a null association was observed amongst overweight men (HR=1.04, 0.89, 1.22); and, for men with a normal body mass index, television/video time was associated with a non-significant risk decrease (HR=0.82, 95%CI: 0.66, 1.01). Similar patterns were observed for total daily sitting and television/video time in advanced prostate cancer and prostate cancer mortality. Sedentary behavior appears to play a limited role in the development of prostate cancer, however we cannot rule out potential effect modification by body mass index or the impact of measurement error on results. PMID:24526287
Gurel, Bora; Lucia, M. Scott; Thompson, Ian M.; Goodman, Phyllis J.; Tangen, Catherine M.; Kristal, Alan R.; Parnes, Howard L.; Hoque, Ashraful; Lippman, Scott M.; Sutcliffe, Siobhan; Peskoe, Sarah B.; Drake, Charles G.; Nelson, William G.; De Marzo, Angelo M.; Platz, Elizabeth A.
2014-01-01
Background Chronic inflammation is hypothesized to influence prostate cancer development, although a definitive link has not been established. Methods Prostate cancer cases (N=191) detected on a for-cause (clinically indicated) or end-of-study (protocol directed) biopsy, and frequency-matched controls (N=209), defined as negative for cancer on an end-of-study biopsy, were sampled from the placebo arm of the Prostate Cancer Prevention Trial. Inflammation prevalence and extent in benign areas of biopsy cores were visually assessed using digital images of H&E stained sections. Logistic regression was used to estimate associations. Results 86.2% of cases and 78.2% of controls had at least one biopsy core (of 3 assessed) with inflammation in benign areas, most of which was chronic. Men who had at least one biopsy core with inflammation had 1.78 (95% CI 1.04–3.06) times the odds of prostate cancer compared with men who had zero cores with inflammation. The association was stronger for high-grade disease (Gleason sum 7–10, N=94; odds ratio [OR]=2.24, 95% CI 1.06–4.71). These patterns were present when restricting to cases and controls in whom intraprostatic inflammation was the least likely to have influenced biopsy recommendation because their PSA was low (<2 ng/mL at biopsy). Conclusion Inflammation, most of which was chronic, was common in benign prostate tissue, and was positively associated with prostate cancer, especially high-grade. The association did not appear to be due to detection bias. Impact This study supports an etiologic link between inflammation and prostate carcinogenesis, and suggests an avenue for prevention by mitigating intraprostatic inflammation. PMID:24748218
Du, Lifen; Lei, Yongfang; Chen, Jinglou; Song, Hongping; Wu, Xinying
2017-01-01
Cadmium (Cd) is an environmental pollutant with reproductive toxicity. Swertia mileensis is used in Chinese medicine for the treatment of prostatic deficits and named as Qing Ye Dan (QYD). This study was undertaken to investigate the potential protective effects of QYD against Cd-induced prostatic deficits. Rat model of prostatic deficits was induced by 0.2 mg/kg/d CdCl2 subcutaneous injection for 15 days. The prostatic oxidative stress was evaluated by detecting the levels of malondialdehyde, nitric oxide, reduced/ oxidized glutathione, total sulfhydryl groups and enzymatic antioxidant status. The prostatic inflammation was estimated by testing the levels of pro-inflammatory cytokines. The levels of epithelial-mesenchymal transition (EMT) markers E-cadherin, fibronectin, vimentin and α-smooth muscle actin were measured by qPCR analysis. Additionally, the prostatic expressions of transforming growth factor-β1 (TGF-β1), type I TGF-β receptor (TGF-βRI), Smad2, phosphorylation-Smad2 (p-Smad2), Smad3, p-Smad3, Smad7, nuclear related factor-2 (Nrf-2), heme oxygenase-1 (HO-1), B-cell CLL/lymphoma (Bcl)-2 and Bcl-2-associated X protein (Bax) were measured by western blot assay. It was found that QYD ameliorated the Cd-induced prostatic oxidative stress and inflammation, attenuated prostatic EMT, inhibited the TGF-β1/Smad pathway, increased Bcl-2/Bax ratio and enhanced the activity of Nrf-2/HO-1 pathway. These results showed that QYD could ameliorate Cd-induced prostatic deficits via modulating Nrf-2/HO-1 and TGF-β1/Smad pathways. © 2017 The Author(s). Published by S. Karger AG, Basel.
Ganzer, Roman; Bründl, Johannes; Koch, Daniel; Wieland, Wolf F; Burger, Maximilian; Blana, Andreas
2015-01-01
To determine which pretreatment clinical parameters were predictive of a low prostate-specific antigen (PSA) nadir following high-intensity focused ultrasound (HIFU) treatment. Retrospective study of patients with clinically localised prostate cancer undergoing HIFU at a single centre between December 1997 and September 2009. Whole-gland treatment was applied. Patients also included if they had previously undergone transurethral resection of the prostate (TURP). TURP was also conducted simultaneously to HIFU. Biochemical failure based on Phoenix definition (PSA nadir + 2). Univariate and multivariate analysis of pretreatment clinical parameters conducted to assess those factors predictive of a PSA nadir ≤0.2 and >0.2 ng/ml. Mean (SD) follow-up was 6.2 (2.8) years; median (range) was 6.3 (1.1-12.2) years. Kaplan-Meier estimate of biochemical disease-free survival rate at 8 years was 83 and 48 % for patients achieving a PSA nadir of ≤0.2 and >0.2 ng/ml, respectively. Prostate volume and incidental finding of cancer were significant predictors of low PSA nadir (≤0.2 ng/ml). Prostate volume and incidental finding of cancer could be predictors for oncologic success of HIFU based on post-treatment PSA nadir.
Stefani, Eduardo De; Boffetta, Paolo L; Ronco, Alvaro; Deneo-Pellegrini, Hugo
2016-01-01
In order to determine the role of meat consumption and related nutrients in the etiology of prostate cancer we conducted a case-control study among Uruguayan men in the time period 1998-2007. The study included 464 cases and 472 controls, frequency matched for age and residence. Both series were drawn from the four major public hospitals in Montevideo. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (95 % CI) of prostate cancer by quartiles of meat intake and related nutrients. The highest vs. the lowest quartile of intake of total meat (OR = 5.19, 95 % CI 3.46-7.81), red meat (OR = 4.64, 95 % CI 3.10-6.95), and processed meat (OR = 1.78, 95% CI 1.22-2.59) were associated with increased risk of prostate cancer. Meat nutrients were directly associated with the risk of prostate cancer (OR for cholesterol 5.61, 95 % CI 3.75-8.50). Moreover, both total meat and red meat displayed higher risks among obese patients. This study suggests that total and red meat and meat nutrients may play a role in the etiology of prostate cancer in Uruguay.
Sjoberg, Daniel D; Vickers, Andrew J; Assel, Melissa; Dahlin, Anders; Poon, Bing Ying; Ulmert, David; Lilja, Hans
2018-06-01
Prostate-specific antigen (PSA) screening reduces prostate cancer deaths but leads to harm from overdiagnosis and overtreatment. To determine the long-term risk of prostate cancer mortality using kallikrein blood markers measured at baseline in a large population of healthy men to identify men with low risk for prostate cancer death. Study based on the Malmö Diet and Cancer cohort enrolling 11 506 unscreened men aged 45-73 yr during 1991-1996, providing cryopreserved blood at enrollment and followed without PSA screening to December 31, 2014. We measured four kallikrein markers in the blood of 1223 prostate cancer cases and 3028 controls. Prostate cancer death (n=317) by PSA and a prespecified statistical model based on the levels of four kallikrein markers. Baseline PSA predicted prostate cancer death with a concordance index of 0.86. In men with elevated PSA (≥2.0ng/ml), predictive accuracy was enhanced by the four-kallikrein panel compared with PSA (0.80 vs 0.73; improvement 0.07; 95% confidence interval 0.04, 0.10). Nearly half of men aged 60+ yr with elevated PSA had a four-kallikrein panel score of <7.5%, translating into 1.7% risk of prostate cancer death at 15 yr-a similar estimate to that of a man with a PSA of 1.6ng/ml. Men with a four-kallikrein panel score of ≥7.5% had a 13% risk of prostate cancer death at 15 yr. A prespecified statistical model based on four kallikrein markers (commercially available as the 4Kscore) reclassified many men with modestly elevated PSA, to have a low long-term risk of prostate cancer death. Men with elevated PSA but low scores from the four-kallikrein panel can be monitored rather than being subject to biopsy. Men with elevated prostate-specific antigen (PSA) are often referred for prostate biopsy. However, men with elevated PSA but low scores from the four-kallikrein panel can be monitored rather than being subject to biopsy. Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Zinc Intake and Risk of Prostate Cancer: Case-Control Study and Meta-Analysis.
Mahmoud, Abeer M; Al-Alem, Umaima; Dabbous, Firas; Ali, Mohamed M; Batai, Ken; Shah, Ebony; Kittles, Rick A
2016-01-01
Zinc is an essential dietary element that has been implicated in the pathogenesis of prostate cancer, a cancer that disproportionately affects men of African descent. Studies assessing the association of zinc intake and prostate cancer have yielded inconsistent results. Furthermore, very little is known about the relationship between zinc intake and prostate cancer among African Americans. We examined the association between self-reported zinc intake and prostate cancer in a hospital-based case-control study of African Americans. We then compared our results with previous studies by performing a meta-analysis to summarize the evidence regarding the association between zinc and prostate cancer. Newly diagnosed African American men with histologically confirmed prostate cancer (n = 127) and controls (n = 81) were recruited from an urban academic urology clinic in Washington, DC. Controls had higher zinc intake, with a mean of 14 mg/day versus 11 mg/day for cases. We observed a non-significant, non-linear increase in prostate cancer when comparing tertiles of zinc intake (OR <6.5 vs 6.5-12.5mg/day 1.8, 95% CI: 0.6,5.6; OR <6.5 vs >12.5mg/day 1.3, 95% CI: 0.2,6.5). The pooled estimate from 17 studies (including 3 cohorts, 2 nested case-control, 11 case-control studies, and 1 randomized clinical trial, with a total of 111,199 participants and 11,689 cases of prostate cancer) was 1.07hi vs lo 95% CI: 0.98-1.16. Using a dose-response meta-analysis, we observed a non-linear trend in the relationship between zinc intake and prostate cancer (p for nonlinearity = 0.0022). This is the first study to examine the relationship between zinc intake in black men and risk of prostate cancer and systematically evaluate available epidemiologic evidence about the magnitude of the relationship between zinc intake and prostate cancer. Despite of the lower intake of zinc by prostate cancer patients, our meta-analysis indicated that there is no evidence for an association between zinc intake and prostate cancer.
Technology diffusion and diagnostic testing for prostate cancer
Schroeck, Florian R.; Kaufman, Samuel R.; Jacobs, Bruce L.; Skolarus, Ted A.; Miller, David C.; Weizer, Alon Z.; Montgomery, Jeffrey S.; Wei, John T.; Shahinian, Vahakn B.; Hollenbeck, Brent K.
2013-01-01
Purpose While the dissemination of robotic prostatectomy and intensity-modulated radiotherapy (IMRT) may fuel increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with receipt of prostate specific antigen (PSA) testing and prostate biopsy. Methods In this retrospective cohort study, we included 117,857 men age 66 and older from the 5% sample of Medicare beneficiaries living in the Surveillance Epidemiology and End Results (SEER) areas from 2003 – 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or IMRT per population in a healthcare market (i.e., hospital referral region). We assessed the association of technology penetration with rates of PSA testing and prostate biopsy with generalized estimating equations. Results High technology penetration was associated with increased rates of PSA testing (442 versus 425 per 1,000 person-years, p<0.01) and similar rates of prostate biopsy (10.1 versus 9.9 per 1,000 person-years, p=0.69). The impact of technology penetration on PSA testing and prostate biopsy was much smaller than the effect of age, race, and comorbidity (e.g., PSA testing rate per 1,000 person-years: 485 versus 373 for men with only one versus 3+ co-morbid conditions, p<0.01). Conclusions Increased technology penetration was associated with slightly higher rates of PSA testing and no change in prostate biopsy rates. Collectively, our findings temper concerns that adoption of new technology accelerates diagnostic testing for prostate cancer. PMID:23669564
Introduction to Mobile Trajectory Based Services: A New Direction in Mobile Location Based Services
NASA Astrophysics Data System (ADS)
Khokhar, Sarfraz; Nilsson, Arne A.
The mandate of E911 gave birth to the idea of Location Based Services (LBS) capitalizing on the knowledge of the mobile location. The underlying estimated location is a feasible area. There is yet another class of mobile services that could be based on the mobility profiling of a mobile user. The mobility profile of a mobile user is a set of the routine trajectories of his or her travel paths. We called such services as Mobile Trajectory Based Services (MTBS). This paper introduces MTBS and functional architecture of an MTBS system. Suitability of different location estimation technologies for MTBS has been discussed and supported with simulation results.
NASA Astrophysics Data System (ADS)
Holmgren, J.; Tulldahl, H. M.; Nordlöf, J.; Nyström, M.; Olofsson, K.; Rydell, J.; Willén, E.
2017-10-01
A system was developed for automatic estimations of tree positions and stem diameters. The sensor trajectory was first estimated using a positioning system that consists of a low precision inertial measurement unit supported by image matching with data from a stereo-camera. The initial estimation of the sensor trajectory was then calibrated by adjustments of the sensor pose using the laser scanner data. Special features suitable for forest environments were used to solve the correspondence and matching problems. Tree stem diameters were estimated for stem sections using laser data from individual scanner rotations and were then used for calibration of the sensor pose. A segmentation algorithm was used to associate stem sections to individual tree stems. The stem diameter estimates of all stem sections associated to the same tree stem were then combined for estimation of stem diameter at breast height (DBH). The system was validated on four 20 m radius circular plots and manual measured trees were automatically linked to trees detected in laser data. The DBH could be estimated with a RMSE of 19 mm (6 %) and a bias of 8 mm (3 %). The calibrated sensor trajectory and the combined use of circle fits from individual scanner rotations made it possible to obtain reliable DBH estimates also with a low precision positioning system.
Coelho, Rafael F; Chauhan, Sanket; Sivaraman, Ananthakrishnan; Palmer, Kenneth J; Orvieto, Marcelo A; Rocco, Bernardo; Coughlin, Geoff; Patel, Vipul R
2012-02-01
To describe a technical modification during robotic-assisted simple prostatectomy (RASP) aiming to decrease perioperative blood loss, shorten the length of hospital stay and eliminate the need of postoperative continuous bladder irrigation. To describe perioperative outcomes, pathological findings and functional outcomes of our single-surgeon series using this technique. We analysed six consecutive patients who underwent RASP using our technical modification between February and September 2010. Transrectal ultrasonography (TRUS) guided prostate biopsy was performed in all cases and revealed benign prostatic hyperplasia in two cases and benign prostatic hyperplasia plus chronic prostatitis in four cases. The mean estimated prostate volume in the TRUS was 157 ± 74 (range 90-300) mL and the average preoperative International Prostate Symptom score was 19.8 ± 9.6 (10-32). Two patients were in urinary retention before surgery. Our technique of RASP includes the standard operative steps reported during open and laparoscopic simple prostatectomy; however, with the addition of some technical modifications during the reconstructive part of the procedure. Following the resection of the adenoma, instead of performing the classical 'trigonization' of the bladder neck and closure of the prostatic capsule, we propose three modified surgical steps: plication of the posterior prostatic capsule, a modified van Velthoven continuous vesico-urethral anastomosis and, finally, suture of the anterior prostatic capsule to the anterior bladder wall. The patients' average age was 69 ± 4.9 (63-74) years; the mean estimated blood loss was 208 ± 66 (100-300) mL and the mean operative time was 90 ± 17.6 (75-120) min. All patients were discharged on postoperative day 1 without the need of continuous bladder irrigation at any time after RASP. No blood transfusion or perioperative complications were reported. The mean weight of the surgical specimen was 145 ± 41.6 (84-186) g. Histopathological evaluation revealed benign prostatic hyperplasia plus chronic prostatitis in five patients and prostatic adenocarcinoma (Gleason score 3+3, pT1a) with negative surgical margins in one patient. The mean serum prostate-specific antigen level decreased from 7 ± 2.5 (4.2-11) ng/mL preoperatively to 1.05 ± 0.8 (0.2-2.5) after RASP. Significant improvement from baseline was reported in the average International Prostate Symptom score (average preoperative vs postoperative, 19.8 ± 9.6 vs 5.5 ± 2.5, P= 0.01) and in mean maximum urine flow (average preoperative vs postoperative 7.75 ± 3.3 vs 19 ± 4.5 mL/s, P= 0.019) at 2 months after RASP. All patients were continent (defined as the use of no pads) at 2 months after RASP. Our modified technique of RASP is a safe and feasible option for treatment of lower urinary tract symptoms caused by large prostatic adenomas. Potential advantages of our technique include reduced blood loss, lower blood transfusion rates and shorter length of hospital stay with no need of postoperative continuous bladder irrigation. Larger series with longer follow-up are necessary to determine long-term outcomes in comparison to open simple prostatectomy or to the standard technique of RASP. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.
NASA Astrophysics Data System (ADS)
Mozaffari, Ahmad; Vajedi, Mahyar; Azad, Nasser L.
2015-06-01
The main proposition of the current investigation is to develop a computational intelligence-based framework which can be used for the real-time estimation of optimum battery state-of-charge (SOC) trajectory in plug-in hybrid electric vehicles (PHEVs). The estimated SOC trajectory can be then employed for an intelligent power management to significantly improve the fuel economy of the vehicle. The devised intelligent SOC trajectory builder takes advantage of the upcoming route information preview to achieve the lowest possible total cost of electricity and fossil fuel. To reduce the complexity of real-time optimization, the authors propose an immune system-based clustering approach which allows categorizing the route information into a predefined number of segments. The intelligent real-time optimizer is also inspired on the basis of interactions in biological immune systems, and is called artificial immune algorithm (AIA). The objective function of the optimizer is derived from a computationally efficient artificial neural network (ANN) which is trained by a database obtained from a high-fidelity model of the vehicle built in the Autonomie software. The simulation results demonstrate that the integration of immune inspired clustering tool, AIA and ANN, will result in a powerful framework which can generate a near global optimum SOC trajectory for the baseline vehicle, that is, the Toyota Prius PHEV. The outcomes of the current investigation prove that by taking advantage of intelligent approaches, it is possible to design a computationally efficient and powerful SOC trajectory builder for the intelligent power management of PHEVs.
Navigation in GPS Denied Environments: Feature-Aided Inertial Systems
2010-03-01
21] Brown , R. G. and Hwang , P. Y. C., Introduction to Random Signals and Applied Kalman Filtering, Third Edition, John Wiley & Sons, Inc., New York...knowledge is provided in [17]. An online (extended Kalman filter-based) method for calculating a trajectory by tracking features at an unknown location on...Finally, the trajectory error is estimated using these associated features in a Kalman estimator. The next couple of paragraphs will explain these
NASA Technical Reports Server (NTRS)
Nishimura, T.
1975-01-01
This paper proposes a worst-error analysis for dealing with problems of estimation of spacecraft trajectories in deep space missions. Navigation filters in use assume either constant or stochastic (Markov) models for their estimated parameters. When the actual behavior of these parameters does not follow the pattern of the assumed model, the filters sometimes result in very poor performance. To prepare for such pathological cases, the worst errors of both batch and sequential filters are investigated based on the incremental sensitivity studies of these filters. By finding critical switching instances of non-gravitational accelerations, intensive tracking can be carried out around those instances. Also the worst errors in the target plane provide a measure in assignment of the propellant budget for trajectory corrections. Thus the worst-error study presents useful information as well as practical criteria in establishing the maneuver and tracking strategy of spacecraft's missions.
Guevara Hidalgo, Esteban; Nemoto, Takahiro; Lecomte, Vivien
2017-06-01
Rare trajectories of stochastic systems are important to understand because of their potential impact. However, their properties are by definition difficult to sample directly. Population dynamics provides a numerical tool allowing their study, by means of simulating a large number of copies of the system, which are subjected to selection rules that favor the rare trajectories of interest. Such algorithms are plagued by finite simulation time and finite population size, effects that can render their use delicate. In this paper, we present a numerical approach which uses the finite-time and finite-size scalings of estimators of the large deviation functions associated to the distribution of rare trajectories. The method we propose allows one to extract the infinite-time and infinite-size limit of these estimators, which-as shown on the contact process-provides a significant improvement of the large deviation function estimators compared to the standard one.
Under-sampling trajectory design for compressed sensing based DCE-MRI.
Liu, Duan-duan; Liang, Dong; Zhang, Na; Liu, Xin; Zhang, Yuan-ting
2013-01-01
Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) needs high temporal and spatial resolution to accurately estimate quantitative parameters and characterize tumor vasculature. Compressed Sensing (CS) has the potential to accomplish this mutual importance. However, the randomness in CS under-sampling trajectory designed using the traditional variable density (VD) scheme may translate to uncertainty in kinetic parameter estimation when high reduction factors are used. Therefore, accurate parameter estimation using VD scheme usually needs multiple adjustments on parameters of Probability Density Function (PDF), and multiple reconstructions even with fixed PDF, which is inapplicable for DCE-MRI. In this paper, an under-sampling trajectory design which is robust to the change on PDF parameters and randomness with fixed PDF is studied. The strategy is to adaptively segment k-space into low-and high frequency domain, and only apply VD scheme in high-frequency domain. Simulation results demonstrate high accuracy and robustness comparing to VD design.
Botoseneanu, Anda; Allore, Heather G; Gahbauer, Evelyne A; Gill, Thomas M
2013-07-01
Gender-specific trajectories of lower extremity function (LEF) and the potential for bias in LEF estimation due to differences in survival have been understudied. We evaluated longitudinal data from 690 initially nondisabled adults age 70 or older from the Precipitating Events Project. LEF was assessed every 18 months for 12 years using a modified Short Physical Performance Battery (mSPPB). Hierarchical linear models with adjustments for length-of-survival estimated the intraindividual trajectory of LEF and differences in trajectory intercept and slope between men and women. LEF declined following a nonlinear trajectory. In the full sample, and among participants with high (mSPPB 10-12) and intermediate (mSPPB 7-9) baseline LEF, the rate-of-decline in mSPPB was slower in women than in men, with no gender differences in baseline mSPPB scores. Among participants with low baseline LEF (mSPPB ≤6), men had a higher starting mSPPB score, whereas women experienced a deceleration in the rate-of-decline over time. In all groups, participants who survived longer had higher starting mSPPB scores and slower rates-of-decline compared with those who died sooner. Over the course of 12 years, older women preserve LEF better than men. Nonadjustment for differences in survival results in overestimating the level and underestimating the rate-of-decline in LEF over time.
Kok, Esther T; Bohnen, Arthur M; Jonkheijm, Rikkert; Gouweloos, Jochem; Groeneveld, Frans P M J; Thomas, Siep; Bosch, J L H Ruud
2006-10-01
To determine which case-definition of clinical benign prostatic hyperplasia (BPH) has the best predictive value for general practitioner visits for lower urinary tract symptoms (LUTS) suggestive of BPH. The incidence and prevalence rates of general practitioner visits for LUTS were also determined. A longitudinal, population-based study from 1995 to 2003 was conducted among 1688 men aged 50 to 78 years old. Data were collected on physical urologic parameters, quality of life, and symptom severity as determined from the International Prostate Symptom Score. Information on health-care-seeking behavior of all participants was collected from the general practitioner (GP) record using a computerized search engine and an additional manual check of the electronically selected files. The incidence and prevalence rate of the men at risk was 19.6% and 14.0%, respectively, and these rates increased with age. For sensitivity and the positive predictive value, the case-definition of clinical BPH as an International Prostate Symptom Score greater than 7 had the best predictive value for GP visits for LUTS within 2 years after baseline. Because only marginal improvement (greater specificity but lower sensitivity) in the prediction of GP visits for LUTS was possible by adding information on prostate volume and flow, for the prediction of future GP visits for LUTS suggestive of BPH, we suggest that the International Prostate Symptom Score questionnaire be used and that estimation of the prostate volume and flow is not required.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nguyen, Paul L., E-mail: E-pnguyen@LROC.harvard.ed; Harvard Medical School, Boston, MA; Chen, Ming H.
Background: Brachytherapy for prostate cancer can be technically challenging in men with small prostates ({<=}20 cc), but it is unknown whether their outcomes are different than those of men with larger prostates. Methods and Materials: We studied 6,416 men treated with brachytherapy in one of 21 community-based practices. Cox regression and Fine and Gray's regression were used to determine whether volume {<=}20 cc was associated with a higher risk of all-cause mortality (ACM) or prostate cancer-specific mortality (PCSM), respectively, after adjustment for other known prognostic factors. Results: 443 patients (6.9%) had a prostate volume {<=}20 cc. After a median follow-upmore » of 2.91 years (interquartile range, 1.06-4.79), volume {<=}20 cc was associated with a significantly higher risk of ACM (adjusted hazard ratio = 1.33 [95% CI 1.08-1.65], p = 0.0085) with 3-year estimates of ACM for {<=}20 cc vs. >20 cc of 13.0% vs. 6.9% (p = 0.028). Only 23 men (0.36%) have died of prostate cancer, and no difference was seen in PCSM by volume (p = 0.4). Conclusion: Men with small prostates at the time of implant had a 33% higher risk of ACM, and the underlying cause of this remains uncertain. No increase in PCSM was observed in men with volume {<=}20cc, suggesting that a small prostate should not in itself be a contraindication for brachytherapy, but inasmuch as absolute rates of PCSM were small, further follow-up will be needed to confirm this finding.« less
A critical review of the epidemiology of Agent Orange/TCDD and prostate cancer.
Chang, Ellen T; Boffetta, Paolo; Adami, Hans-Olov; Cole, Philip; Mandel, Jack S
2014-10-01
To inform risk assessment and regulatory decision-making, the relationship between 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and prostate cancer requires clarification. This article systematically and critically reviews the epidemiologic evidence on the association between exposure to TCDD or Agent Orange, a TCDD-contaminated herbicide used during the Vietnam War, and prostate cancer risk. Articles evaluated include 11 studies of three cohorts, four case-control or cross-sectional studies, and three case-only studies of military veterans with information on estimated Agent Orange or TCDD exposure; 13 studies of seven cohorts, one case-control study, and eight proportionate morbidity or mortality studies of Vietnam veterans without information on Agent Orange exposure; 11 cohort studies of workers with occupational exposure to TCDD; and two studies of one community cohort with environmental exposure to TCDD. The most informative studies, including those of Vietnam veterans involved in Agent Orange spraying or other handling, herbicide manufacturing or spraying workers with occupational TCDD exposure, and community members exposed to TCDD through an industrial accident, consistently reported no significant increase in prostate cancer incidence or mortality. Only some potentially confounded studies of Vietnam veterans compared with the general population, studies with unreliable estimates of Agent Orange exposure, and analyses of selected subgroups of Vietnam veterans reported positive associations. Overall, epidemiologic research offers no consistent or convincing evidence of a causal relationship between exposure to Agent Orange or TCDD and prostate cancer. More accurate exposure assessment is needed in large epidemiologic studies to rule out a causal association more conclusively.
Kote-Jarai, Zsofia; Easton, Douglas F.; Stanford, Janet L.; Ostrander, Elaine A.; Schleutker, Johanna; Ingles, Sue A.; Schaid, Daniel; Thibodeau, Stephen; Dörk, Thilo; Neal, David; Cox, Angela; Maier, Christiane; Vogel, Walter; Guy, Michelle; Muir, Kenneth; Lophatananon, Artitaya; Kedda, Mary-Anne; Spurdle, Amanda; Steginga, Suzanne; John, Esther M.; Giles, Graham; Hopper, John; Chappuis, Pierre O.; Hutter, Pierre; Foulkes, William D.; Hamel, Nancy; Salinas, Claudia A.; Koopmeiners, Joseph S.; Karyadi, Danielle M.; Johanneson, Bo; Wahlfors, Tiina; Tammela, Teuvo L.; Stern, Mariana C.; Corral, Roman; McDonnell, Shannon K.; Schürmann, Peter; Meyer, Andreas; Kuefer, Rainer; Leongamornlert, Daniel A.; Tymrakiewicz, Malgorzata; Liu, Jo-fen; O'Mara, Tracy; Gardiner, R.A. (Frank); Aitken, Joanne; Joshi, Amit D.; Severi, Gianluca; English, Dallas R.; Southey, Melissa; Edwards, Stephen M.; Amin Al Olama, Ali; Eeles, Rosalind A.
2009-01-01
A recent genome-wide association study found that genetic variants on chromosomes 3, 6, 7, 10, 11, 19 and X were associated with prostate cancer risk. We evaluated the most significant single-nucleotide polymorphisms (SNP) in these loci using a worldwide consortium of 13 groups (PRACTICAL). Blood DNA from 7,370 prostate cancer cases and 5,742 male controls was analyzed by genotyping assays. Odds ratios (OR) associated with each genotype were estimated using unconditional logistic regression. Six of the seven SNPs showed clear evidence of association with prostate cancer (P = 0.0007-P = 10−17). For each of these six SNPs, the estimated per-allele OR was similar to those previously reported and ranged from 1.12 to 1.29. One SNP on 3p12 (rs2660753) showed a weaker association than previously reported [per-allele OR, 1.08 (95% confidence interval, 1.00-1.16; P = 0.06) versus 1.18 (95% confidence interval, 1.06-1.31)]. The combined risks associated with each pair of SNPs were consistent with a multiplicative risk model. Under this model, and in combination with previously reported SNPs on 8q and 17q, these loci explain 16% of the familial risk of the disease, and men in the top 10% of the risk distribution have a 2.1-fold increased risk relative to general population rates. This study provides strong confirmation of these susceptibility loci in multiple populations and shows that they make an important contribution to prostate cancer risk prediction. PMID:18708398
Koch, M O; Miller, D A; Butler, R; Lebos, L; Collings, D; Smith, J A
1998-02-01
To determine our accuracy in selecting patients with at least a 10-year life expectancy for aggressive treatment of localized prostate cancer. The medical records of 261 consecutive patients who underwent radical retropubic prostatectomy were submitted to the actuarial division of American General Life and Accident Insurance Company (AGLA) for estimation of life expectancy, excluding the diagnosis of prostate cancer. Survival curves were generated from predicted individual survivals. In patients with less than a 10-year life expectancy, AGLA provided us with the basis for assigning suboptimal survival rates. The mean life expectancy for the group was 15.2 years. Two hundred ten men (80%) were projected to have a life expectancy of more than 10 years, including 27 of 55 (49%) and 4 of 8 (50%) men who were older than or equal to 70 and 75 years of age, respectively. Coronary artery disease and diabetes mellitus were the most common coexisting medical conditions that adversely affected risk as single disease entities. Although clinicians do not estimate life expectancy with the scientific exactitude of an actuary, the ability to assess the patient in person and assimilate pertinent medical information in a less rigid format yields similar results. Selection of men for definitive treatment of localized prostate cancer should be based on the inherent aggressiveness of the disease and the health of the individual and should not be limited by specific age cutoffs. Populations of men undergoing radical prostatectomy are younger and healthier than those in reported series of watchful waiting for prostate cancer.
Slator, Paddy J.; Cairo, Christopher W.; Burroughs, Nigel J.
2015-01-01
We develop a Bayesian analysis framework to detect heterogeneity in the diffusive behaviour of single particle trajectories on cells, implementing model selection to classify trajectories as either consistent with Brownian motion or with a two-state (diffusion coefficient) switching model. The incorporation of localisation accuracy is essential, as otherwise false detection of switching within a trajectory was observed and diffusion coefficient estimates were inflated. Since our analysis is on a single trajectory basis, we are able to examine heterogeneity between trajectories in a quantitative manner. Applying our method to the lymphocyte function-associated antigen 1 (LFA-1) receptor tagged with latex beads (4 s trajectories at 1000 frames s−1), both intra- and inter-trajectory heterogeneity were detected; 12–26% of trajectories display clear switching between diffusive states dependent on condition, whilst the inter-trajectory variability is highly structured with the diffusion coefficients being related by D 1 = 0.68D 0 − 1.5 × 104 nm2 s−1, suggestive that on these time scales we are detecting switching due to a single process. Further, the inter-trajectory variability of the diffusion coefficient estimates (1.6 × 102 − 2.6 × 105 nm2 s−1) is very much larger than the measurement uncertainty within trajectories, suggesting that LFA-1 aggregation and cytoskeletal interactions are significantly affecting mobility, whilst the timescales of these processes are distinctly different giving rise to inter- and intra-trajectory variability. There is also an ‘immobile’ state (defined as D < 3.0 × 103 nm2 s−1) that is rarely involved in switching, immobility occurring with the highest frequency (47%) under T cell activation (phorbol-12-myristate-13-acetate (PMA) treatment) with enhanced cytoskeletal attachment (calpain inhibition). Such ‘immobile’ states frequently display slow linear drift, potentially reflecting binding to a dynamic actin cortex. Our methods allow significantly more information to be extracted from individual trajectories (ultimately limited by time resolution and time-series length), and allow statistical comparisons between trajectories thereby quantifying inter-trajectory heterogeneity. Such methods will be highly informative for the construction and fitting of molecule mobility models within membranes incorporating aggregation, binding to the cytoskeleton, or traversing membrane microdomains. PMID:26473352
Costa, Marcilia P; Feitosa, Anderson C S; Oliveira, Fátima C E; Cavalcanti, Bruno C; da Silva, Eufrânio N; Dias, Gleiston G; Sales, Francisco A M; Sousa, Bruno L; Barroso-Neto, Ito L; Pessoa, Cláudia; Caetano, Ewerton W S; Di Fiore, Stefano; Fischer, Rainer; Ladeira, Luiz O; Freire, Valder N
2016-07-02
Prostate cancer is one of the most common malignant tumors in males and it has become a major worldwide public health problem. This study characterizes the encapsulation of Nor-β-lapachone (NβL) in poly(d,l-lactide-co-glycolide) (PLGA) microcapsules and evaluates the cytotoxicity of the resulting drug-loaded system against metastatic prostate cancer cells. The microcapsules presented appropriate morphological features and the presence of drug molecules in the microcapsules was confirmed by different methods. Spherical microcapsules with a size range of 1.03 ± 0.46 μm were produced with an encapsulation efficiency of approximately 19%. Classical molecular dynamics calculations provided an estimate of the typical adsorption energies of NβL on PLGA. Finally, the cytotoxic activity of NβL against PC3M human prostate cancer cells was demonstrated to be significantly enhanced when delivered by PLGA microcapsules in comparison with the free drug.
Dusek, L; Pavlík, T; Májek, O; Büchler, T; Muzik, J; Maluskova, D; Koptíková, J; Bortlicek, Z; Abrahámová, J
2015-01-01
Cancer burden in the Czech population ranks among the highest worldwide, which introduces a strong need for a prospective modelling of cancer incidence and prevalence rates. Moreover, a prediction of number of cancer patients requiring active antitumor therapy is also an important issue. This paper presents the stage-specific predictions of cancer incidence and prevalence, and the stage- and region-specific patients requiring active antitumor therapy for the most common cancer diagnoses in the Czech Republic for years 2015 and 2020. The stage-specific estimates are also presented with regard to the treatment phase as newly diagnosed patients, patients treated for non-terminal recurrence, and patients treated for terminal recurrence. Data of the Czech National Cancer Registry from 1977 to 2011 has been used for the analysis, omitting the records of patients diagnosed as death certificate only or at autopsy. In total, 1,777,775 incidences have been considered for the estimation using a statistical model utilizing solely the population-based cancer registry data. All estimates have been calculated with respect to the changing demographic structure of the Czech population and the clinical stage at diagnosis. Considering year 2011 as the baseline, we predict 89%, 15%, 31% and 32% increase in prostate, colorectal, female breast and lung cancer incidence, respectively, in 2020 resulting in 13,153, 9,368, 8,695, and 8,604 newly dia-g--nosed cancer patients in that year, respectively. Regarding cancer prevalence in 2020, the estimated increase is 140%, 40%, 51%, and 17% for prostate, colorectal, female breast and lung cancer, respectively, meaning that more than 100,000 prevalent female breast cancer patients as well as more than 100,000 prevalent prostate cancer patients are expected in the Czech Republic. The estimated numbers of patients requiring active antitumor therapy for prostate, colorectal, female breast and lung cancer in the Czech Republic in 2020 are 23,652, 14,006, 14,759 and 8,272; respectively. The analysis documents a serious increase in cancer incidence and prevalence in the Czech Republic in years 2015 and 2020 when compared to the situation in 2011. Regarding the estimated numbers of patients requiring active antitumor therapy, the model confirms a continuous increase that must be accounted for in the future planning of health care in the Czech Republic.
Calculating tumor trajectory and dose-of-the-day using cone-beam CT projections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, Bernard L., E-mail: bernard.jones@ucdenver.edu; Westerly, David; Miften, Moyed
2015-02-15
Purpose: Cone-beam CT (CBCT) projection images provide anatomical data in real-time over several respiratory cycles, forming a comprehensive picture of tumor movement. The authors developed and validated a method which uses these projections to determine the trajectory of and dose to highly mobile tumors during each fraction of treatment. Methods: CBCT images of a respiration phantom were acquired, the trajectory of which mimicked a lung tumor with high amplitude (up to 2.5 cm) and hysteresis. A template-matching algorithm was used to identify the location of a steel BB in each CBCT projection, and a Gaussian probability density function for themore » absolute BB position was calculated which best fit the observed trajectory of the BB in the imager geometry. Two modifications of the trajectory reconstruction were investigated: first, using respiratory phase information to refine the trajectory estimation (Phase), and second, using the Monte Carlo (MC) method to sample the estimated Gaussian tumor position distribution. The accuracies of the proposed methods were evaluated by comparing the known and calculated BB trajectories in phantom-simulated clinical scenarios using abdominal tumor volumes. Results: With all methods, the mean position of the BB was determined with accuracy better than 0.1 mm, and root-mean-square trajectory errors averaged 3.8% ± 1.1% of the marker amplitude. Dosimetric calculations using Phase methods were more accurate, with mean absolute error less than 0.5%, and with error less than 1% in the highest-noise trajectory. MC-based trajectories prevent the overestimation of dose, but when viewed in an absolute sense, add a small amount of dosimetric error (<0.1%). Conclusions: Marker trajectory and target dose-of-the-day were accurately calculated using CBCT projections. This technique provides a method to evaluate highly mobile tumors using ordinary CBCT data, and could facilitate better strategies to mitigate or compensate for motion during stereotactic body radiotherapy.« less
Yano, Masataka; Kitahara, Satoshi; Yasuda, Kosaku; Yamanishi, Tomonori; Nakai, Hideo; Yanagisawa, Ryouzo; Morozumi, Makoto; Homma, Yukio
2004-05-01
To evaluate the extent to which our newly developed questionnaire, the Saitama Prostate Symptom Score (SPSS), for prostatic symptom scoring reflects objective findings in benign prostatic hyperplasia (clinical BPH) and to compare it with the International Prostate Symptom Score (IPSS) with regard to diagnostic sensitivity in clinical BPH. In this study, both the SPSS and the IPSS were self-administered by patients. Free uroflowmetry, a pressure-flow study and the measurement of prostatic volume were carried out. There was no significant correlation between the results of the IPSS questionnaire and the urethral obstruction grade estimated by Schaefer or Abrams-Griffiths nomograms. The total score of the SPSS was correlated with these nomograms (P = 0.0487 and P = 0.0413, respectively). There was no significant correlation between the results of the IPSS questionnaire and the total volume or transition zone volume of the prostate, whereas the total score of the SPSS correlated with the total volume of the gland and transition zone volume (P = 0.0044 and P= 0.0051, respectively). This study revealed the SPSS to correlate with objective findings satisfactorily. However, there are still several aspects of the SPSS which need to be improved upon, and the questionnaire should be studied in larger numbers of patients suffering from lower urinary tract symptoms.
Effects of radiation on the incidence of prostate cancer among Nagasaki atomic bomb survivors.
Kondo, Hisayoshi; Soda, Midori; Mine, Mariko; Yokota, Kenichi
2013-10-01
Atomic bomb survivors have been reported to have an increased risk of some cancers, especially leukemia. However, the risk of prostate cancer in atomic bomb survivors is not known to have been examined previously. This study examined the association between atomic bomb radiation and the incidence of prostate cancer among male Nagasaki atomic bomb survivors. The subjects were classified by distance from the hypocenter into a proximal group (<2 km), a distal group (≥2 km), and an early entrance group (those who entered the region <2 km from the hypocenter within 2 weeks after the explosion). Between 1996 and 2009, 631 new cases of prostate cancer were identified among approximately 18 400 male Nagasaki atomic bomb survivors who were alive in 1996. The Cox proportional hazard model was used to estimate the risk of prostate cancer development, with adjustment for age at atomic bomb explosion, attained age, smoking status, and alcohol consumption. Compared with the distal group, the proximal group had significant increased risks of total, localized, and high-grade prostate cancer (relative risk and 95% confidence interval: 1.51 [1.21-1.89]; 1.80 [1.26-2.57]; and 1.88 [1.20-2.94], respectively). This report is the first known to reveal a significant relationship between atomic bomb radiation and prostate cancer. © 2013 Japanese Cancer Association.
Prostate cancer testing: behaviour, motivation and attitudes among Western Australian men.
Slevin, T J; Donnelly, N; Clarkson, J P; English, D R; Ward, J E
1999-08-16
To estimate the proportion of Western Australian men aged 40-80 years who had been tested for prostate cancer, their experiences of screening and perception of its benefit. Cross-sectional survey (random telephone survey) of Western Australian men conducted in February 1998. 400 men aged 40-80 years from 670 eligible households (60% response rate from contactable households with eligible men). Proportion of respondents tested for prostate cancer (by prostate-specific antigen [PSA] test or digital rectal examination); reasons for having been tested; information provided by the doctor before testing; reasons given for and beliefs about the benefits of testing. Of 391 asymptomatic men, 220 (56%) recalled having been tested for prostate cancer and 167 (43%) had had a PSA test. Of those tested, 86% had their first test in the previous five years. The two most common reasons for testing were media publicity and general practitioner recommendation. Thirty-eight per cent of men tested during the previous five years reported that the doctor did not discuss the "pros and cons" of the test; 39% reported a discussion of less than five minutes' duration; 17% were given printed information before undergoing the test for the first time. Half were "very convinced" of the benefits of testing for prostate cancer. Men are being tested for prostate cancer with minimal pretest counselling or written information.
Prevalence of and Risk Factors for Asymptomatic Inflammatory (NIH-IV) Prostatitis in Chinese Men
Wu, Chunlei; Zhang, Zhifu; Lu, Zheng; Liao, Ming; Zhang, Youjie; Xie, Yuanliang; Guo, Xuefeng; Yu, Xiaoxiang; Yang, Xiaobo; Gao, Yong; Tan, Aihua; Mo, Zengnan
2013-01-01
Background While many investigators have studied symptomatic prostatitis, little research has been done with regard to asymptomatic (NIH-IV) prostatitis. Purpose To describe the prevalence of and risk factors for NIH-IV prostatitis among a large male population. Methods The study population was comprised of 1,868 men at the second phase recruitment of a population-based cohort in China. Asymptomatic and symptomatic men were defined by the National Institutes of Health Chronic Prostatitis (CP) Symptom Index. Meanwhile, EPS specimens and their leukocyte count were collected. Lifestyle and demographic characteristics were obtained through a questionnaire. Results Prevalence of NIH-IV prostatitis was 21.1% among 1,868 asymptomatic men aged 19–78 years and increased with age. After adjusteing for potential confounding variables (age, smoking habits, alcohol drinking habits, education, physical activity, hypertension, dyslipidemia, obesity and diabetes), age remained a significant factor for NIH-IV prostatitis (OR = 1.35; 95% CI = 1.06–1.71; P = 0.01) and the risk of NIH-IV prostatitis was significantly higher in smokers≧15 pack/years than non-smokers (OR = 1.33; 95% CI = 1.01–1.75; P = 0.03). In addition, compared with non-drinkers, the OR of NIH-IV prostatitis in drinkers ≧1 drinks/week was 1.35 (95% CI = 1.03, 1.77, p = 0.02) after adjusting for the other variables above. In addition, having less than a college education may be a risk factor for NIH-IV prostatitis, although a statistically significant difference did not exist in our data (OR = 1.22; 95% CI = 0.97–1.52; P = 0.08). Conclusions Our findings suggest that NIH-IV prostatitis is prevalent in China. Age, smoking, drinking and lower education levels were associated with an increased risk of NIH-IV prostatitis. The prevalence of NIH-IV prostatitis should be taken into account when estimating the total prevalence of CP in future studies. PMID:23967188
Human arm stiffness and equilibrium-point trajectory during multi-joint movement.
Gomi, H; Kawato, M
1997-03-01
By using a newly designed high-performance manipulandum and a new estimation algorithm, we measured human multi-joint arm stiffness parameters during multi-joint point-to-point movements on a horizontal plane. This manipulandum allows us to apply a sufficient perturbation to subject's arm within a brief period during movement. Arm stiffness parameters were reliably estimated using a new algorithm, in which all unknown structural parameters could be estimated independent of arm posture (i.e., constant values under any arm posture). Arm stiffness during transverse movement was considerably greater than that during corresponding posture, but not during a longitudinal movement. Although the ratios of elbow, shoulder, and double-joint stiffness were varied in time, the orientation of stiffness ellipses during the movement did not change much. Equilibrium-point trajectories that were predicted from measured stiffness parameters and actual trajectories were slightly sinusoidally curved in Cartesian space and their velocity profiles were quite different from the velocity profiles of actual hand trajectories. This result contradicts the hypothesis that the brain does not take the dynamics into account in movement control depending on the neuromuscular servo mechanism; rather, it implies that the brain needs to acquire some internal models of controlled objects.
Assessment of the age for a preventive ultrasonographic examination of the prostate in the dog.
Mantziaras, G; Alonge, S; Faustini, M; Luvoni, G C
2017-09-15
The prostate commonly develops benign prostatic hyperplasia (BPH) in dogs over 5 years, while in aged dogs other pathological findings might be revealed by ultrasonographic exam. The aim of the present study was to estimate the most suitable age for a preventive ultrasonographic examination of the prostate in the dog. The prostate of 1003 intact male dogs of 64 different breeds, of different ages (1-18 years) and bodyweights (2-55 kg) was evaluated with ultrasound, irrespective of the reason for clinical examination. The age of each dog was expressed as the ratio between the actual age and the maximum longevity expected for the breed. Dogs were divided in two groups based on breeds' life expectancy as short life (SL) and long life (LL). The size of the prostate (normal, enlarged or small) and the presence of abnormal sonographic findings were recorded for each dog. The results of the present study indicate that the most suitable age for a preventive ultrasonographic exam of the prostate in the dog is approximately at 40% of its expected longevity, both in short and long life breeds, because at this age there is a strong possibility to be able to detect abnormal prostatic findings. In 47.5% of the dogs at least one abnormal finding of the prostate was revealed by ultrasonographic exam, while dogs with long life expectancy showed a significantly higher prevalence of abnormalities, than dogs with short life expectancy. The most frequent findings were the increase of prostatic size (33.5%) and the presence of at least one cyst (33.6%), with no difference between SL and LL dogs. In conclusion, a preventive examination of the prostate starting at 40% of expected longevity in dogs of short and long life breeds is strongly recommended for early detection of abnormalities, for scheduling specific follow up and for suggesting effective therapeutic protocols. Copyright © 2017 Elsevier Inc. All rights reserved.
An incremental DPMM-based method for trajectory clustering, modeling, and retrieval.
Hu, Weiming; Li, Xi; Tian, Guodong; Maybank, Stephen; Zhang, Zhongfei
2013-05-01
Trajectory analysis is the basis for many applications, such as indexing of motion events in videos, activity recognition, and surveillance. In this paper, the Dirichlet process mixture model (DPMM) is applied to trajectory clustering, modeling, and retrieval. We propose an incremental version of a DPMM-based clustering algorithm and apply it to cluster trajectories. An appropriate number of trajectory clusters is determined automatically. When trajectories belonging to new clusters arrive, the new clusters can be identified online and added to the model without any retraining using the previous data. A time-sensitive Dirichlet process mixture model (tDPMM) is applied to each trajectory cluster for learning the trajectory pattern which represents the time-series characteristics of the trajectories in the cluster. Then, a parameterized index is constructed for each cluster. A novel likelihood estimation algorithm for the tDPMM is proposed, and a trajectory-based video retrieval model is developed. The tDPMM-based probabilistic matching method and the DPMM-based model growing method are combined to make the retrieval model scalable and adaptable. Experimental comparisons with state-of-the-art algorithms demonstrate the effectiveness of our algorithm.
Saad, F; Ivanescu, C; Phung, D; Loriot, Y; Abhyankar, S; Beer, T M; Tombal, B; Holmstrom, S
2017-01-01
Background: We investigated the impact of skeletal-related events (SREs) on health-related quality of life (HRQoL) in patients with metastatic castration-resistant prostate cancer (mCRPC) in phase III trials of enzalutamide versus placebo. Methods: Patients with mCRPC experiencing at least one SRE during AFFIRM and PREVAIL were assessed for trajectory-adjusted mean change in HRQoL by first SRE using Functional Assessment of Cancer Therapy-Prostate (FACT-P; AFFIRM, three domains, and PREVAIL, nine domains) and EQ-5D (PREVAIL) instruments. Results: First SREs caused HRQoL deterioration in both trials. Spinal cord compression had the largest impact, with clinically meaningful reductions in seven of nine FACT-P domains in PREVAIL and all three in AFFIRM (mean (95% confidence interval (CI)) change in FACT-P total score –16.95 (–26.47, –7.44) and –9.69 (–16.10, –3.27), respectively). In PREVAIL, first SREs caused clinically meaningful declines in EQ-5D utility index, irrespective of category; spinal cord compression had the largest impact (mean (95% CI) change –0.24 (–0.39, –0.08)). In AFFIRM, FACT-P and FACT-General total scores showed clinically meaningful declines after radiation/surgery to bone. Conclusions: SREs were associated with clinically meaningful functional declines in the daily lives of patients with mCRPC. Spinal cord compression had the largest impact on HRQoL. PMID:28045115
Green, Mark A; Eitel, Jacob A; Fletcher, James W; Mathias, Carla J; Tann, Mark A; Gardner, Thomas; Koch, Michael O; Territo, Wendy; Polson, Heather; Hutchins, Gary D
2017-03-01
This study was performed to estimate the human radiation dosimetry for [ 68 Ga]Ga-HBED-CC (PSMA-11) ( 68 Ga PSMA-11). Under an RDRC-approved research protocol, we evaluated the biodistribution and pharmacokinetics of 68 Ga PSMA-11 with serial PET imaging following intravenous administration to nine prostate cancer patients in whom clinical [ 11 C]acetate PET/CT exams had been independently performed under Expanded Access IND 118,204. List-mode imaging was performed over the initial 0-10min post-injection with the pelvis in the field-of-view. Whole-body images were acquired, pelvis-to-head, at 15, 60, and 90-min post-injection. Additional images of the pelvis were acquired at 40-min and 115-min, and voided urine collected from each subject at 48-min and 120-min post-injection. Radiation dosimetry estimates were calculated from these data using the OLINDA software package. Renal uptake was high and relatively invariant, ranging from 11% to 14% of the injected dose between 15 and 90-min post-injection. Radioactivity collected in the voided urine accounted for 14% of the injected dose over a period of 120-min. Lymph nodes and skeletal metastases suspicious for prostate cancer recurrence were detected in a greater number of patients using 68 Ga PSMA-11 than using 11 C-acetate. Kidneys are the critical organ following 68 Ga PSMA-11 administration, receiving an estimated dose of 0.413mGy/MBq. This study confirms that the kidneys will be the critical organ following intravenous administration of 68 Ga PSMA-11, and provided data consistent with the expectation that 68 Ga PSMA-11 will be superior to [ 11 C]acetate for defining sites of recurrence in prostate cancer patients presenting with biochemical relapse. Copyright © 2016 Elsevier Inc. All rights reserved.
Garcia-Reyes, Kirema; Nguyen, Hao G; Zagoria, Ronald J; Shinohara, Katsuto; Carroll, Peter R; Behr, Spencer C; Westphalen, Antonio C
2017-09-20
The purpose of this study was to estimate the impact of lesion visibility with transrectal ultrasound on the prediction of clinically significant prostate cancer with transrectal ultrasound-magnetic resonance imaging fusion biopsy. This HIPAA (Health Insurance Portability and Accountability Act) compliant, institutional review board approved, retrospective study was performed in 178 men who were 64.7 years old with prostate specific antigen 8.9 ng/ml. They underwent transrectal ultrasound-magnetic resonance imaging fusion biopsy from January 2013 to September 2016. Visible lesions on magnetic resonance imaging were assigned a PI-RADS™ (Prostate Imaging Reporting and Data System), version 2 score of 3 or greater. Transrectal ultrasound was positive when a hypoechoic lesion was identified. We used a 3-level, mixed effects logistic regression model to determine how transrectal ultrasound-magnetic resonance imaging concordance predicted the presence of clinically significant prostate cancer. The diagnostic performance of the 2 methods was estimated using ROC curves. A total of 1,331 sextants were targeted by transrectal ultrasound-magnetic resonance imaging fusion or systematic biopsies, of which 1,037 were negative, 183 were Gleason score 3 + 3 and 111 were Gleason score 3 + 4 or greater. Clinically significant prostate cancer was diagnosed by transrectal ultrasound and magnetic resonance imaging alone at 20.5% and 19.7% of these locations, respectively. Men with positive imaging had higher odds of clinically significant prostate cancer than men without visible lesions regardless of modality (transrectal ultrasound OR 14.75, 95% CI 5.22-41.69, magnetic resonance imaging OR 12.27, 95% CI 6.39-23.58 and the 2 modalities OR 28.68, 95% CI 14.45-56.89, all p <0.001). The ROC AUC to detect clinically significant prostate cancer using the 2 methods (0.85, 95% CI 0.81-0.89) was statistically greater than that of transrectal ultrasound alone (0.80, 95% CI 0.76-0.85, p = 0.001) and magnetic resonance imaging alone (0.83, 95% CI 0.79-0.87, p = 0.04). The sensitivity and specificity of transrectal ultrasound were 42.3% and 91.6%, and the sensitivity and specificity of magnetic resonance imaging were 62.2% and 84.1%, respectively. Lesion visibility on magnetic resonance imaging or transrectal ultrasound denotes a similar probability of clinically significant prostate cancer. This probability is greater when each examination is positive. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Mitcham, Trevor; Taghavi, Houra; Long, James; Wood, Cayla; Fuentes, David; Stefan, Wolfgang; Ward, John; Bouchard, Richard
2017-09-01
Photoacoustic (PA) imaging is capable of probing blood oxygen saturation (sO 2 ), which has been shown to correlate with tissue hypoxia, a promising cancer biomarker. However, wavelength-dependent local fluence changes can compromise sO 2 estimation accuracy in tissue. This work investigates using PA imaging with interstitial irradiation and local fluence correction to assess precision and accuracy of sO 2 estimation of blood samples through ex vivo bovine prostate tissue ranging from 14% to 100% sO 2 . Study results for bovine blood samples at distances up to 20 mm from the irradiation source show that local fluence correction improved average sO 2 estimation error from 16.8% to 3.2% and maintained an average precision of 2.3% when compared to matched CO-oximeter sO 2 measurements. This work demonstrates the potential for future clinical translation of using fluence-corrected and interstitially driven PA imaging to accurately and precisely assess sO 2 at depth in tissue with high resolution.
Shih, H-J; Kao, M-C; Tsai, P-S; Fan, Y-C; Huang, C-J
2017-09-01
Clinical observations indicated an increased risk of developing prostate cancer in gout patients. Chronic inflammation is postulated to be one crucial mechanism for prostate carcinogenesis. Allopurinol, a widely used antigout agent, possesses potent anti-inflammation capacity. We elucidated whether allopurinol decreases the risk of prostate cancer in gout patients. We analyzed data retrieved from Taiwan National Health Insurance Database between January 2000 and December 2012. Patients diagnosed with gout during the study period with no history of prostate cancer and who had never used allopurinol were selected. Four allopurinol use cohorts (that is, allopurinol use (>365 days), allopurinol use (181-365 days), allopurinol use (91-180 days) and allopurinol use (31-90 days)) and one cohort without using allopurinol (that is, allopurinol use (No)) were included. The study end point was the diagnosis of new-onset prostate cancer. Multivariable Cox proportional hazards regression and propensity score-adjusted Cox regression models were used to estimate the association between the risk of prostate cancer and allopurinol treatment in gout patients after adjusting for potential confounders. A total of 25 770 gout patients (aged between 40 and 100 years) were included. Multivariable Cox regression analyses revealed that the risk of developing prostate cancer in the allopurinol use (>365 days) cohort was significantly lower than the allopurinol use (No) cohort (adjusted hazard ratio (HR)=0.64, 95% confidence interval (CI)=0.45-0.9, P=0.011). After propensity score adjustment, the trend remained the same (adjusted HR=0.66, 95% CI=0.46-0.93, P=0.019). Long-term (more than 1 year) allopurinol use may associate with a decreased risk of prostate cancer in gout patients.
Sex steroid hormone metabolism in relation to risk of aggressive prostate cancer
Black, Amanda; Pinsky, Paul F.; Grubb, Robert L.; Falk, Roni T.; Hsing, Ann W.; Chu, Lisa; Meyer, Tamra; Veenstra, Timothy D.; Xu, Xia; Yu, Kai; Ziegler, Regina G.; Brinton, Louise A.; Hoover, Robert N.; Cook, Michael B.
2014-01-01
Background The combined action of androgens and estrogens—specifically their balance—may play a role in prostate carcinogenesis but existing evidence is sparse and inconsistent. We investigated associations between serum sex steroid hormones, including estrogen metabolites, and risk of aggressive prostate cancer. Methods In a case-control study nested within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial cohort we measured serum estrone, estradiol and 13 estrogen metabolites, in the 2-, 4, or 16-hydroxylation pathways, using a liquid chromatography-tandem mass spectrometry assay. Cases (n=195) were non-Hispanic white men aged 55–70 years when diagnosed with aggressive prostate cancer (stage III or IV and/or Gleason ≥7). Controls (n=195) were non-Hispanic white men without prostate cancer who were frequency-matched to cases by age and year at blood draw, time since baseline screen. Only men with serum testosterone and sex hormone-binding globulin measured previously were eligible. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (95%CI). Results Risk of aggressive prostate cancer was strongly inversely associated with estradiol:testosterone ratio (OR4th quartile vs. 1st =0.27, 95% CI 0.12–0.59, p trend=0.003) and positively associated with 2:16α-hydroxyestrone ratio (OR4th quartile vs. 1st =2.44, 95% CI 1.34–4.45, p trend=0.001). Estradiol, estrone and estrogen metabolites were unrelated to risk. Conclusions Our findings suggest that sex steroid hormones, specifically the estrogen-androgen balance, may be important in the development of aggressive prostate cancer. Impact Improved understanding of the hormonal etiology of prostate cancer is critical for prevention and therapeutic interventions. PMID:25178985
Frequency of Unnecessarily Biopsies among Patients with Suspicion of Prostate Cancer in Syrian Men.
Bachour, Dala-Maria; Chahin, Emil; Al-Fahoum, Sahar
2015-01-01
The prevalence of prostate cancer is considered high in many countries, and screening tests are very important in order to detect prostate cancer in its early stages; however false positivity with these screening tests means that a lot of patients undergo unnecessary biopsy, which is an invasive procedure, for the confirmatory test. The purpose of this study was to estimate the frequency of unnecessary biopsy cases in patients referred for prostate biopsy in one of the most important and overload cancer centers in Syria. Retrospective data for a period of four years between January 2009 and December 2012 were collected in Al- Bayrouni University Medical hospital in Damascus, Syria. The patients from whom data were collected were referred to our histopathological department because of elevated prostate specific antigen (PSA) serum or an abnormal digital rectal examination (DRE). All patients underwent prostatic TRUS-guided biopsies. Diagnosis of prostate cancer (PCa) or benign prostatic hyperplasia (BPH) was based on histopathological examination and prostate cancers cases were graded and scored according to the Gleason score system. For the 406 patients referred to biopsy, the mean±SD age was 58.4 ±23.3 years. The mean ± SD PSA level was 49.2±21.5 ng/ ml. Of the total we found 237 patients diagnosed with PCa (58. 4%), 166 patients with BPH (40.9%) and 3 cases were unable to be diagnosed (0.7%) because of biopsy collection errors. Our study shows that a high percentage of patients are undergoing unnecessary biopsy, which suggests that the performed screening tests had a high level of false positive and may need re-evaluation.
Martin, Richard M.; Geybels, Milan S.; Stanford, Janet L.; Shui, Irene; Eeles, Rosalind; Easton, Doug; Kote‐Jarai, Zsofia; Amin Al Olama, Ali; Benlloch, Sara; Muir, Kenneth; Giles, Graham G; Wiklund, Fredrik; Gronberg, Henrik; Haiman, Christopher A; Schleutker, Johanna; Nordestgaard, Børge G.; Travis, Ruth C; Neal, David; Pashayan, Nora; Khaw, Kay‐Tee; Blot, William; Thibodeau, Stephen; Maier, Christiane; Kibel, Adam S; Cybulski, Cezary; Cannon‐Albright, Lisa; Brenner, Hermann; Park, Jong; Kaneva, Radka; Batra, Jyotsna; Teixeira, Manuel R; Pandha, Hardev; Donovan, Jenny; Munafò, Marcus R.
2016-01-01
Coffee consumption has been shown in some studies to be associated with lower risk of prostate cancer. However, it is unclear if this association is causal or due to confounding or reverse causality. We conducted a Mendelian randomisation analysis to investigate the causal effects of coffee consumption on prostate cancer risk and progression. We used two genetic variants robustly associated with caffeine intake (rs4410790 and rs2472297) as proxies for coffee consumption in a sample of 46,687 men of European ancestry from 25 studies in the PRACTICAL consortium. Associations between genetic variants and prostate cancer case status, stage and grade were assessed by logistic regression and with all‐cause and prostate cancer‐specific mortality using Cox proportional hazards regression. There was no clear evidence that a genetic risk score combining rs4410790 and rs2472297 was associated with prostate cancer risk (OR per additional coffee increasing allele: 1.01, 95% CI: 0.98,1.03) or having high‐grade compared to low‐grade disease (OR: 1.01, 95% CI: 0.97,1.04). There was some evidence that the genetic risk score was associated with higher odds of having nonlocalised compared to localised stage disease (OR: 1.03, 95% CI: 1.01, 1.06). Amongst men with prostate cancer, there was no clear association between the genetic risk score and all‐cause mortality (HR: 1.00, 95% CI: 0.97,1.04) or prostate cancer‐specific mortality (HR: 1.03, 95% CI: 0.98,1.08). These results, which should have less bias from confounding than observational estimates, are not consistent with a substantial effect of coffee consumption on reducing prostate cancer incidence or progression. PMID:27741566
Nordström, Tobias; Bratt, Ola; Örtegren, Joakim; Aly, Markus; Adolfsson, Jan; Grönberg, Henrik
2016-01-01
The aim of this study was to determine whether educational length affects prostate-specific antigen (PSA) testing and the time to prostate biopsy for men with raised PSA values. Using register data on all men in Stockholm County in 2013 (n = 1,052,841), the limited-duration point prevalence of PSA testing and time between test and prostate biopsy or repeat testing were analysed. Patterns of follow-up were assessed using Kaplan-Meier product limit estimators and Cox proportional hazard models. Educational length was categorized as short (≤ 9 years), intermediate (10-12 years) or long (≥ 13 years). PSA testing increased with educational length in all age groups. Among men aged 50-69 years, 61% with long and 54% with short education had had a PSA test within the preceding 10 years (p < 0.001). In men with PSA 4-10 ng/ml, 40% [95% confidence interval (CI) 38-41] with long and 27% (95% CI 26-29) with short education underwent a prostate biopsy within 12 months. After adjusting for PSA level and age, educational length was still associated with the chance of having a prostate biopsy in men with PSA 4-10 ng/ml (hazard ratio 1.22, 95% CI 1.12-1.31), but not in men with higher PSA values. PSA testing increased with educational length. Men with long education were more likely to have a prostate biopsy after an increased PSA value below 10 ng/ml than men with short education. These differences may contribute to the worse prostate cancer outcomes observed among men with lower socioeconomic status.
Implications of pleiotrophin in human PC3 prostate cancer cell growth in vivo.
Tsirmoula, Sotiria; Dimas, Kostas; Hatziapostolou, Maria; Lamprou, Margarita; Ravazoula, Panagiota; Papadimitriou, Evangelia
2012-10-01
Pleiotrophin (PTN) is a heparin-binding growth factor with diverse functions related to tumor growth, angiogenesis, and metastasis. Pleiotrophin seems to have a significant role in prostate cancer cell growth and to mediate the stimulatory actions of other factors that affect prostate cancer cell functions. However, all studies carried out up to date are in vitro, using different types of human prostate cancer cell lines. The aim of the present work was to study the role of endogenous PTN in human prostate cancer growth in vivo. For this purpose, human prostate cancer PC3 cells were stably transfected with a plasmid vector, bearing the antisense PTN sequence, in order to inhibit PTN expression (AS-PC3). Migration, apoptosis, and adhesion on osteoblastic cells were measured in vitro. In vivo, PC3 cells were s.c. injected into male NOD/SCID mice, and tumor growth, survival rates, angiogenesis, apoptosis, and the number of metastasis were estimated. Pleiotrophin depletion resulted in a decreased migration capability of AS-PC3 cells compared with the corresponding mock-transfected or the non-transfected PC3 cells, as well as increased apoptosis and decreased adhesiveness to osteoblastic cells in vitro. In prostate cancer NOD/SCID mouse xenografts, PTN depletion significantly suppressed tumor growth and angiogenesis and induced apoptosis of cancer cells. In addition, PTN depletion decreased the number of metastases, providing a survival benefit for the animals bearing AS-PC3 xenografts. Our data suggest that PTN is implicated in human prostate cancer growth in vivo and could be considered a potential target for the development of new therapeutic approaches for prostate cancer. © 2012 Japanese Cancer Association.
Paksarian, Diana; Cui, Lihong; Angst, Jules; Ajdacic-Gross, Vladeta; Rössler, Wulf; Merikangas, Kathleen R
2016-10-01
Epidemiologic evidence indicates that most of the general population will experience a mental health disorder at some point in their lives. However, few prospective population-based studies have estimated trajectories of risk for mental disorders from young through middle adulthood to estimate the proportion of individuals who experience persistent mental disorder across this age period. To describe the proportion of the population who experience persistent mental disorder across adulthood and to estimate latent trajectories of disorder risk across this age period. A population-based, prospective cohort study was conducted between 1979 and 2008 in the canton of Zurich, Switzerland. A stratified random sample of 591 Swiss citizens was enrolled in 1978 at ages 19 years (men) and 20 years (women); 7 interviews were performed during a 29-year period. Men were sampled from military enrollment records and women from electoral records. From those initially enrolled, participants with high levels of psychiatric symptoms were oversampled for follow-up. Data analysis was performed from July 28, 2015, to June 8, 2016. Latent trajectories, estimated using growth mixture modeling, of past-year mood/anxiety disorder (ie, major depressive episode, phobias, panic, generalized anxiety disorder, and obsessive-compulsive disorder), substance use disorder (ie, drug abuse or dependence and alcohol abuse or dependence), and any mental disorder (ie, any of the above) assessed during in-person semistructured interviews at each wave. Diagnoses were based on DSM-III, DSM-III-R, and DSM-IV criteria. Of the 591 participants at baseline, 299 (50.6%) were female. Persistent mental health disorder across multiple study waves was rare. Among 252 individuals (42.6%) who participated in all 7 study waves, only 1.2% met criteria for disorder every time. Growth mixture modeling identified 3 classes of risk for any disorder across adulthood: low (estimated prevalence, 40.0%; 95% CI, -8.7% to 88.9%), increasing-decreasing (estimated prevalence, 15.3%; 95% CI, 1.0% to 29.6%), and increasing (estimated prevalence, 44.7%; 95% CI, -0.9% to 90.1%). Although no classes were characterized by persistently high disorder risk, for those in the increasing-decreasing class, risk was high from the late 20s to early 40s. Sex-specific models indicated 4 trajectory classes for women but only 3 for men. Persistently high mental health disorder risk across 3 decades of adulthood was rare in this population-based sample. Identifying early determinants of sex-specific risk trajectories would benefit prevention efforts.
Sokoll, Lori J; Zhang, Zhen; Chan, Daniel W; Reese, Adam C; Bivalacqua, Trinity J; Partin, Alan W; Walsh, Patrick C
2016-02-01
In this study we evaluate an ultrasensitive prostate specific antigen assay in patients with prostate cancer after radical prostatectomy to predict long-term biochemical recurrence-free survival. A total of 754 men who underwent radical prostatectomy and had an undetectable prostate specific antigen after surgery (less than 0.1 ng/ml) were studied. Prostate specific antigen was measured in banked serum specimens with an ultrasensitive assay (Hybritech® PSA, Beckman Coulter Access® 2) using a cutoff of 0.01 ng/ml. Prostate specific antigen was also measured in 44 men after cystoprostatectomy who had no pathological evidence of prostate cancer with the Hybritech assay and with the Quanterix AccuPSA™ assay. Of the 754 men 17% (131) experienced biochemical recurrence (median 4.0 years). Those men without biochemical recurrence (83%, 623) had a minimum of 5 years of followup (median 11). Prostate specific antigen was less than 0.01 ng/ml in 93.4% of men with no biochemical recurrence, whereas 30.5% of men with biochemical recurrence had a prostate specific antigen of 0.01 ng/ml or greater. On multivariate analysis postoperative prostate specific antigen at a 0.01 ng/ml cutoff, pathological stage and Gleason score, and surgical margins were significant independent predictors of biochemical recurrence risk. Kaplan-Meier estimates for mean biochemical recurrence-free survival were 15.2 years (95% CI 14.9-15.6) for prostate specific antigen less than 0.01 ng/ml and 10.0 years (95% CI 8.4-11.5) for prostate specific antigen 0.01 ng/ml or greater (p <0.0001). Biochemical recurrence-free rates 11 years after surgery were 86.1% (95% CI 83.2-89.0) for prostate specific antigen less than 0.01 ng/ml and 48.9% (95% CI 37.5-60.3) for prostate specific antigen 0.01 ng/ml or greater (p <0.0001). Prostate specific antigen concentrations in 44 men after cystoprostatectomy were all less than 0.03 ng/ml, with 95.4% less than 0.01 ng/ml. In men with a serum prostate specific antigen less than 0.1 ng/ml after radical prostatectomy a tenfold lower cutoff (0.01 ng/ml) stratified biochemical recurrence-free survival and was a significant independent predictor of biochemical recurrence, as were pathological features. Prostate specific antigen concentrations in men without pathological evidence of prostate cancer suggest that a higher prostate specific antigen concentration (0.03 ng/ml) in the ultrasensitive range may be needed to define the detection threshold. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Müller, Arndt-Christian, E-mail: arndt-christian.mueller@med.uni-tuebingen.de; Eckert, Franziska; Paulsen, Frank
2016-02-01
Purpose: To assess the efficacy of individual sentinel node (SN)-guided pelvic intensity modulated radiation therapy (IMRT) by determining nodal clearance rate [(n expected nodal involvement − n observed regional recurrences)/n expected nodal involvement] in comparison with surgically staged patients. Methods and Materials: Data on 475 high-risk prostate cancer patients were examined. Sixty-one consecutive patients received pelvic SN-based IMRT (5 × 1.8 Gy/wk to 50.4 Gy [pelvic nodes + individual SN] and an integrated boost with 5 × 2.0 Gy/wk to 70.0 Gy to prostate + [base of] seminal vesicles) and neo-/adjuvant long-term androgen deprivation therapy; 414 patients after SN–pelvic lymph node dissection were used to calculate the expected nodal involvement rate for the radiation therapymore » sample. Biochemical control and overall survival were estimated for the SN-IMRT patients using the Kaplan-Meier method. The expected frequency of nodal involvement in the radiation therapy group was estimated by imputing frequencies of node-positive patients in the surgical sample to the pattern of Gleason, prostate-specific antigen, and T category in the radiation therapy sample. Results: After a median follow-up of 61 months, 5-year OS after SN-guided IMRT reached 84.4%. Biochemical control according to the Phoenix definition was 73.8%. The nodal clearance rate of SN-IMRT reached 94%. Retrospective follow-up evaluation is the main limitation. Conclusions: Radiation treatment of pelvic nodes individualized by inclusion of SNs is an effective regional treatment modality in high-risk prostate cancer patients. The pattern of relapse indicates that the SN-based target volume concept correctly covers individual pelvic nodes. Thus, this SN-based approach justifies further evaluation, including current dose-escalation strategies to the prostate in a larger prospective series.« less
Møller, Mette H; Kristiansen, Ivar S; Beisland, Christian; Rørvik, Jarle; Støvring, Henrik
2016-10-01
To estimate changes in the stage distribution of prostate cancer during the time period where opportunistic prostate-specific antigen (PSA) testing was introduced. Cancer stage, age, and year of diagnosis were obtained for all men aged >50 years diagnosed with prostate cancer in Norway during the period 1980-2010. Three calendar-time periods (1980-1989, 1990-2000, and 2001-2010) and three age groups (50-65, 66-74, and ≥75 years) were defined. Birth cohorts were categorised into four intervals: ≤1915, 1916-1925, 1926-1940 and ≥1941. We used Poisson regressions to conduct both a time period and cohort-based analysis of trends in the incidence of localised, regional, and distant cancer for each combination of age groups and calendar-time periods or birth cohorts, respectively. Additionally, we explored the effect of cohorts on the stage-specific incidence graphically with a Poisson regression using 5-year age groups, and by estimating cumulative incidence rates for each birth cohort. The annual incidence of localised cancers among men aged 50-65 and 66-74 years rose from 41.4 and 255.2 per 100 000, respectively, before the introduction of PSA testing to 137.9 and 418.7 in 2001-2010 afterwards, corresponding to 3.3 [95% confidence interval (CI) 3.1-3.5] and 1.6 (95% CI 1.6-1.7) fold increases. The incidence of regional cancers increased by a factor seven among men aged <75 years. The incidence of distant cancers in men aged ≥75 years decreased by 29% (95% CI 25-33%). These findings were confirmed in the cohort-based approach. Opportunistic PSA testing substantially increased the incidence of localised and regional prostate cancers among men aged 50-74 years, which was not fully compensated by the 30% decrease in incidence of distant prostate cancers in older men. © 2015 The Authors BJU International © 2015 BJU International Published by John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joensuu, Greetta; International Comprehensive Cancer Center Docrates, Helsinki; Joensuu, Timo
Purpose: To estimate the safety and tolerability of daily administration of 250 mg of gefitinib given concurrently with three-dimensional conformal radiotherapy for patients with nonmetastatic prostate cancer. Methods and Materials: A total of 42 patients with T2-T3N0M0 tumors were treated in a nonrandomized single-center study. A prostate-specific antigen (PSA) level of <20 and a good performance status (WHO, 0-1) were required. Adjuvant or neoadjuvant hormone treatments were not allowed. A daily regimen of 250 mg of gefitinib was started 1 week before radiation therapy began and lasted for the duration of radiation therapy. A dose of 50.4 Gy (1.8 Gy/day)more » was administered to the tumor, prostate, and seminal vesicles, followed by a 22-Gy booster (2 Gy/day) for a total dose of 72.4 Gy. Correlative studies included analysis of epidermal growth factor receptor (EGFR), EGFRvIII, and phosphorylated EGFR in tumors and tumor necrosis factor, interleukin-1{alpha} (IL-1{alpha}), and IL-6 in serum. Results: Maximum tolerated dose was not reached in phase I (12 patients), and 30 additional patients were treated in phase II. Thirty (71.4%) patients completed trial medication. Dose-limiting toxicities were recorded for 16 (38.1%) patients, the most common of which was a grade 3 to 4 increase in transaminase (6 patients). After a median follow-up of 38 months, there were no deaths due to prostate cancer. The estimated PSA relapse-free survival rate at 4 years (Kaplan-Meier) was 97%, the salvage therapy-free survival rate was 91%, and the overall survival rate was 87%. These figures compared favorably with those of matched patients treated with radiation only at higher doses. Conclusions: The combination of gefitinib and radiation is reasonably well tolerated and has promising activity against nonmetastatic prostate cancer.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nanda, Akash, E-mail: ananda@partners.or; Chen, M.-H.; Moran, Brian J.
2010-05-01
Purpose: To identify clinical factors associated with prostate cancer-specific mortality (PCSM), adjusting for comorbidity, in elderly men with intermediate-risk prostate cancer treated with brachytherapy alone or in conjunction with external beam radiation therapy. Methods and Materials: The study cohort comprised 1,978 men of median age 71 (interquartile range, 66-75) years with intermediate-risk disease (Gleason score 7, prostate-specific antigen (PSA) 20 ng/mL or less, tumor category T2c or less). Fine and Gray's multivariable competing risks regression was used to assess whether prevalent cardiovascular disease (CVD), age, treatment, year of brachytherapy, PSA level, or tumor category was associated with the risk ofmore » PCSM. Results: After a median follow-up of 3.2 (interquartile range, 1.7-5.4) years, the presence of CVD was significantly associated with a decreased risk of PCSM (adjusted hazard ratio, 0.20; 95% CI 0.04-0.99; p = 0.05), whereas an increasing PSA level was significantly associated with an increased risk of PCSM (adjusted hazard ratio 1.14; 95% CI 1.02-1.27; p = 0.02). In the absence of CVD, cumulative incidence estimates of PCSM were higher (p = 0.03) in men with PSA levels above as compared with the median PSA level (7.3 ng/mL) or less; however, in the setting of CVD there was no difference (p = 0.27) in these estimates stratified by the median PSA level (6.9 ng/mL). Conclusions: In elderly men with intermediate-risk prostate cancer, CVD status is a negative predictor of PCSM and affects the prognostic capacity of pretreatment PSA level. These observations support the potential utility of prerandomization stratification by comorbidity to more accurately assess prognostic factors and treatment effects within this population.« less
Depaoli, Sarah
2013-06-01
Growth mixture modeling (GMM) represents a technique that is designed to capture change over time for unobserved subgroups (or latent classes) that exhibit qualitatively different patterns of growth. The aim of the current article was to explore the impact of latent class separation (i.e., how similar growth trajectories are across latent classes) on GMM performance. Several estimation conditions were compared: maximum likelihood via the expectation maximization (EM) algorithm and the Bayesian framework implementing diffuse priors, "accurate" informative priors, weakly informative priors, data-driven informative priors, priors reflecting partial-knowledge of parameters, and "inaccurate" (but informative) priors. The main goal was to provide insight about the optimal estimation condition under different degrees of latent class separation for GMM. Results indicated that optimal parameter recovery was obtained though the Bayesian approach using "accurate" informative priors, and partial-knowledge priors showed promise for the recovery of the growth trajectory parameters. Maximum likelihood and the remaining Bayesian estimation conditions yielded poor parameter recovery for the latent class proportions and the growth trajectories. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
Translational Regulation of PTEN/MMAC1 Expression in Prostate Cancer
2005-05-01
Ac reporting burden for this collection of information is estimated to average 1 hour per response , including the time for reviewing instructions... responsible for constitutive production of the PTEN mRNAs with shorter 5’-UTRs in prostate cancer cells which would be compatible for cap-dependent...LIMITATION 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON OF ABSTRACT OF PAGES a. REPORT b. ABSTRACT c. THIS PAGE 19b. TELEPHONE NUMBER (include area U U U UU
SU-F-T-258: Efficacy of Exit Fluence-Based Dose Calculation for Prostate Radiation Therapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siebers, J; Gardner, J; Neal, B
Purpose: To investigate the efficacy of exit-fluence-based dose computation for prostate radiotherapy by determining if it estimates true dose more accurately than the original planning dose. Methods: Virtual exit-fluencebased dose computation was performed for 19 patients, each with 9–12 repeat CT images. For each patient, a 78 Gy treatment plan was created utilizing 5 mm CTV-to-PTV and OAR-to-PRV margins. A Monte Carlo framework was used to compute dose and exit-fluence images for the planning image and for each repeat CT image based on boney-anatomyaligned and prostate-centroid-aligned CTs. Identical source particles were used for the MC dose-computations on the planning andmore » repeat CTs to maximize correlation. The exit-fluence-based dose and image were computed by multiplying source particle weights by FC(x,y)=FP(x,y)/FT(x,y), where (x,y) are the source particle coordinates projected to the exit-fluence plane and we denote the dose/fluence from the plan by (DP,FP), from the repeat-CT as (DT,FT), and the exit-fluence computation by (DFC,FFC). DFC mimics exit-fluence backprojection through the planning image as FT=FFC. Dose estimates were intercompared to judge the efficacy of exit-fluence-based dose computation. Results: Boney- and prostate-centroid aligned results are combined as there is no statistical difference between them, yielding 420 dose comparisons per dose-volume metric. DFC is more accurate than DP for 46%, 33%, and 44% of cases in estimating CTV D98, D50, and D2 respectively. DFC improved rectum D50 and D2 estimates 54% and 49% respectively and bladder D50 and D2 47 and 49% respectively. While averaged over all patients and images DFC and DP were within 3.1% of DT, they differed from DT by as much as 22% for GTV D98, 71% for the Bladder D50, 17% for Bladder D2, 19% for Rectum D2. Conclusion: Exit-fluence based dose computations infrequently improve CTV or OAR dose estimates and should be used with caution. Research supported in part by Varian Medical Systems.« less
Li, Chunyu; Zeliadt, Steven B; Hall, Ingrid J; Smith, Judith Lee; Ekwueme, Donatus U; Moinpour, Carol M; Penson, David F; Thompson, Ian M; Keane, Thomas E; Ramsey, Scott D
2013-12-01
Informal care plays an important role in the overall care for people with cancer. This study estimates lost productivity and informal caregiving and associated costs among partner caregivers of localized prostate cancer patients within 1 year after diagnosis. We applied data from the Family and Cancer Therapy Selection study, a three-wave self-administered survey among patients diagnosed with localized prostate cancer and their partner caregivers in multiple clinics in the USA. Time spent was measured by the sum of working hours lost, informal caregiving hours performed, and hours spent on household chores. The national median income for women 55 years or older was used to calculate costs associated with the time spent using the opportunity cost method. Descriptive and bivariate analyses were conducted. The average working hours decreased from 14.0 h/week (SD = 17.6) to 10.9 h/week (SD = 15.9), without a significant change in responsibility/intensity at work. The mean annual time spent on informal caregiving and household chores was 65.9 h/year (SD = 172.4) and 76.2 h/year (SD = 193.3), respectively. The mean annual economic burden among partner caregivers was US$6,063 (range US$571-US$47,105) in 2009 dollars accounted for by a mean of 276.2 h (range 26-2,146) in the study sample. The time spent on informal caregiving and household chores varied by patient and caregiver characteristics. Pilot estimates on non-medical economic burden among partner caregivers (spouses) during the initial phase of the treatment provide important information for comprehensive estimation of disease burden and can be used in cost-effectiveness analyses of prostate cancer interventions.
An Estimate of the Incidence of Prostate Cancer in Africa: A Systematic Review and Meta-Analysis
Aderemi, Adewale Victor; Iseolorunkanmi, Alexander; Oyedokun, Ayo; Ayo, Charles K.
2016-01-01
Background Prostate cancer (PCa) is rated the second most common cancer and sixth leading cause of cancer deaths among men globally. Reports show that African men suffer disproportionately from PCa compared to men from other parts of the world. It is still quite difficult to accurately describe the burden of PCa in Africa due to poor cancer registration systems. We systematically reviewed the literature on prostate cancer in Africa and provided a continent-wide incidence rate of PCa based on available data in the region. Methods A systematic literature search of Medline, EMBASE and Global Health from January 1980 to June 2015 was conducted, with additional search of Google Scholar, International Association of Cancer Registries (IACR), International Agency for Research on Cancer (IARC), and WHO African region websites, for studies that estimated incidence rate of PCa in any African location. Having assessed quality and consistency across selected studies, we extracted incidence rates of PCa and conducted a random effects meta-analysis. Results Our search returned 9766 records, with 40 studies spreading across 16 African countries meeting our selection criteria. We estimated a pooled PCa incidence rate of 22.0 (95% CI: 19.93–23.97) per 100,000 population, and also reported a median incidence rate of 19.5 per 100,000 population. We observed an increasing trend in PCa incidence with advancing age, and over the main years covered. Conclusion Effective cancer registration and extensive research are vital to appropriately quantifying PCa burden in Africa. We hope our findings may further assist at identifying relevant gaps, and contribute to improving knowledge, research, and interventions targeted at prostate cancer in Africa. PMID:27073921
Smith, Matthew R; Saad, Fred; Rathkopf, Dana E; Mulders, Peter F A; de Bono, Johann S; Small, Eric J; Shore, Neal D; Fizazi, Karim; Kheoh, Thian; Li, Jinhui; De Porre, Peter; Todd, Mary B; Yu, Margaret K; Ryan, Charles J
2017-07-01
In the COU-AA-302 trial, abiraterone acetate plus prednisone significantly increased overall survival for patients with chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC). Limited information exists regarding response to subsequent androgen signaling-directed therapies following abiraterone acetate plus prednisone in patients with mCRPC. We investigated clinical outcomes associated with subsequent abiraterone acetate plus prednisone (55 patients) and enzalutamide (33 patients) in a post hoc analysis of COU-AA-302. Prostate-specific antigen (PSA) response was assessed. Median time to PSA progression was estimated using the Kaplan-Meier method. The PSA response rate (≥50% PSA decline, unconfirmed) was 44% and 67%, respectively. The median time to PSA progression was 3.9 mo (range 2.6-not estimable) for subsequent abiraterone acetate plus prednisone and 2.8 mo (range 1.8-not estimable) for subsequent enzalutamide. The majority of patients (68%) received intervening chemotherapy before subsequent abiraterone acetate plus prednisone or enzalutamide. While acknowledging the limitations of post hoc analyses and high censoring (>75%) in both treatment groups, these results suggest that subsequent therapy with abiraterone acetate plus prednisone or enzalutamide for patients who progressed on abiraterone acetate is associated with limited clinical benefit. This analysis showed limited clinical benefit for subsequent abiraterone acetate plus prednisone or enzalutamide in patients with metastatic castration-resistant prostate cancer following initial treatment with abiraterone acetate plus prednisone. This analysis does not support prioritization of subsequent abiraterone acetate plus prednisone or enzalutamide following initial therapy with abiraterone acetate plus prednisone. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Determination of trajectories of fireballs using seismic network data
NASA Astrophysics Data System (ADS)
Ishihara, Y.
2006-12-01
Fireballs, Bolides, which are caused by high velocity passages of meteoroids through the atmosphere, generate shockwaves. Meteor shockwave provide us very important information (arrival time and amplitude) to study meteor physics. The shockwave arrival time data enable us to determine trajectories of the fireballs. On the other hand, the shockwave amplitude tells us size and ablation history of the meteoroid. Infrasound observation is one of the ways of detecting bolide shockwaves. However, we have no infrasound observational networks extends for large area with enough spatial distribution for determination of trajectories and estimate ablation histories. We have only a few infrasound arrays that have three or four elements, in the Japanese islands. Last decade, digital seismic networks are greatly improved for the purpose of monitoring micro earthquakes. Those seismic networks are quite sensitive for detecting micro ground vibration, and then those networks could detect not only seismic wave generated by earthquakes, but also ground oscillations generated by coupling of meteor shockwave with the ground near station. Last years, I analyses this kind of ground motion data recorded by seismic network, as meteor shockwave signals. For example, we estimate some great fireball's aerial path from arrival times of shockwaves (e.g., Ishihara et. al., 2003 Earth Planets, and Space, 2004 Geophysical Research. Letters.; Pujol et al., 2006 Planetary and Space Science), and we estimate sizes and ablation history of some great fireball and a meteorite fall (Ishihara et al., 2004 Meteoroids2004). In Japan, some great fireball falls occurred during 2004 to 2005. In this presentation, I show the trajectories of these fireballs determined from shockwave analysis. Some fireballs trajectories are also determined from photographic records. The trajectories determined from shockwave and that from photos show good agreement.
Entropy of Ultrasound-Contrast-Agent Velocity Fields for Angiogenesis Imaging in Prostate Cancer.
van Sloun, Ruud J G; Demi, Libertario; Postema, Arnoud W; Jmch De La Rosette, Jean; Wijkstra, Hessel; Mischi, Massimo
2017-03-01
Prostate cancer care can benefit from accurate and cost-efficient imaging modalities that are able to reveal prognostic indicators for cancer. Angiogenesis is known to play a central role in the growth of tumors towards a metastatic or a lethal phenotype. With the aim of localizing angiogenic activity in a non-invasive manner, Dynamic Contrast Enhanced Ultrasound (DCE-US) has been widely used. Usually, the passage of ultrasound contrast agents thought the organ of interest is analyzed for the assessment of tissue perfusion. However, the heterogeneous nature of blood flow in angiogenic vasculature hampers the diagnostic effectiveness of perfusion parameters. In this regard, quantification of the heterogeneity of flow may provide a relevant additional feature for localizing angiogenesis. Statistics based on flow magnitude as well as its orientation can be exploited for this purpose. In this paper, we estimate the microbubble velocity fields from a standard bolus injection and provide a first statistical characterization by performing a spatial entropy analysis. By testing the method on 24 patients with biopsy-proven prostate cancer, we show that the proposed method can be applied effectively to clinically acquired DCE-US data. The method permits estimation of the in-plane flow vector fields and their local intricacy, and yields promising results (receiver-operating-characteristic curve area of 0.85) for the detection of prostate cancer.
Specialty Supplements and Prostate Cancer Risk in the VITamins And Lifestyle (VITAL) Cohort
Brasky, Theodore M.; Kristal, Alan R.; Navarro, Sandi L.; Lampe, Johanna W.; Patterson, Ruth E.; Peters, Ulrike; White, Emily
2011-01-01
Although there is evidence from studies of prostate cancer cell lines and rodent models that several supplements may have anti-inflammatory, anti-oxidant, or other anti-cancer properties, few epidemiologic studies have examined the association between non-vitamin, non-mineral, “specialty” supplement use and prostate cancer risk. Participants, 50–76 years, were 35,239 male members of the VITamins And Lifestyle (VITAL) cohort who were residents of western Washington State, and who completed an extensive baseline questionnaire in 2000–2002. Participants responded about their frequency (days/week) and duration (years) of specialty supplement uses. 1,602 incident invasive prostate cancers were obtained from the Surveillance, Epidemiology, and End Results registry. Multivariate-adjusted hazards ratios (HR) and 95% confidence intervals (95% CI) were estimated by Cox proportional hazards models. Any use of grapeseed supplements was associated with a 41% (HR 0.59, 95% CI: 0.40–0.86) reduced risk of total prostate cancer. There were no associations for use of chondroitin, co-enzyme Q10, fish oil, garlic, ginkgo biloba, ginseng, glucosamine, or saw palmetto. Grapeseed may be a potential chemopreventive agent, however as current evidence is limited, it should not yet be promoted for prevention of prostate cancer. PMID:21598177
Assessing the performance of dynamical trajectory estimates
NASA Astrophysics Data System (ADS)
Bröcker, Jochen
2014-06-01
Estimating trajectories and parameters of dynamical systems from observations is a problem frequently encountered in various branches of science; geophysicists for example refer to this problem as data assimilation. Unlike as in estimation problems with exchangeable observations, in data assimilation the observations cannot easily be divided into separate sets for estimation and validation; this creates serious problems, since simply using the same observations for estimation and validation might result in overly optimistic performance assessments. To circumvent this problem, a result is presented which allows us to estimate this optimism, thus allowing for a more realistic performance assessment in data assimilation. The presented approach becomes particularly simple for data assimilation methods employing a linear error feedback (such as synchronization schemes, nudging, incremental 3DVAR and 4DVar, and various Kalman filter approaches). Numerical examples considering a high gain observer confirm the theory.
Assessing the performance of dynamical trajectory estimates.
Bröcker, Jochen
2014-06-01
Estimating trajectories and parameters of dynamical systems from observations is a problem frequently encountered in various branches of science; geophysicists for example refer to this problem as data assimilation. Unlike as in estimation problems with exchangeable observations, in data assimilation the observations cannot easily be divided into separate sets for estimation and validation; this creates serious problems, since simply using the same observations for estimation and validation might result in overly optimistic performance assessments. To circumvent this problem, a result is presented which allows us to estimate this optimism, thus allowing for a more realistic performance assessment in data assimilation. The presented approach becomes particularly simple for data assimilation methods employing a linear error feedback (such as synchronization schemes, nudging, incremental 3DVAR and 4DVar, and various Kalman filter approaches). Numerical examples considering a high gain observer confirm the theory.
In vivo prostate IMRT dosimetry with MOSFET detectors using brass buildup caps
Varadhan, Raj; Miller, John; Garrity, Brenden; Weber, Michael
2006-01-01
The feasibility of using dual bias metal oxide semiconductor field effect transistor (MOSFET) detectors with the new hemispherical brass buildup cap for in vivo dose measurements in prostate intensity‐modulated radiotherapy (IMRT) treatments was investigated and achieved. In this work, MOSFET detectors with brass buildup caps placed on the patient's skin surface on the central axis of the individual IMRT beams are used to determine the maximum entrance dose (Dmax) from the prostate IMRT fields. A general formalism with various correction factors taken into account to predict Dmax entrance dose for the IMRT fields with MOSFETs was developed and compared against predicted dose from the treatment‐planning system (TPS). We achieved an overall accuracy of better than ±5% on all measured fields for both 6‐MV and 10‐MV beams when compared to predicted doses from the Philips Pinnacle 3 and CMS XiO TPSs, respectively. We also estimate the total uncertainty in estimation of MOSFET dose in the high‐sensitivity mode for IMRT therapy to be 4.6%. PACS numbers: 87.53Xd, 87.56Fc PMID:17533354
Barry, Kathryn Hughes; Moore, Lee E; Sampson, Joshua N; Koutros, Stella; Yan, Liying; Meyer, Ann; Reddy, Mahitha; Oler, Andrew J; Cook, Michael B; Fraumeni, Joseph F; Yeager, Meredith; Amundadottir, Laufey T; Berndt, Sonja I
2017-05-23
Chromosome 8q24 has emerged as an important genetic susceptibility region for several cancers, including prostate cancer; however, little is known about the contribution of DNA methylation in this region to risk. We prospectively evaluated DNA methylation at 8q24 in relation to prostate cancer using pre-diagnostic blood samples from 694 prostate cancer cases (including 172 aggressive cases) and 703 controls in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We used logistic regression to estimate odds ratios and 95% confidence intervals. Although none remained significant after adjustment for multiple testing (q>0.05), of the 50 CpG sites meeting quality control, we identified 8 sites that were nominally associated with prostate cancer (P trend <0.05), including 6 correlated (Spearman ρ: 0.20-0.52) sites in POU5F1B and 2 intergenic sites (most significant site: Chr8:128428897 in POU5F1B, P trend =0.01). We also identified two correlated (ρ=0.39) sites in MYC (Chr8:128753187 and Chr8:128753154) that were associated with aggressive (P trend =0.02 and 0.03), but not non-aggressive disease (P trend =0.70 and 0.20; P heterogeneity =0.01 and 4.6 × 10 -3 ). These findings persisted after adjustment for the top 8q24 prostate cancer variants in our study. Although requiring replication, our findings provide some evidence that 8q24 DNA methylation levels may be associated with prostate cancer risk.
Sarafanov, A.G.; Todorov, T.I.; Kajdacsy-Balla, A.; Gray, Michael A.; MacIas, V.; Centeno, J.A.
2008-01-01
Formalin-fixed paraffin-embedded (FFPE) tissue specimens represent a valuable and abundant resource of pathologic material for various biomedical studies. In the present study, we report the application of high-resolution inductively coupled mass-spectrometry (ICP-MS) for quantification of Fe, Zn, Se and Cd in FFPE prostate tissue. These elements have a possible role in the development of prostate diseases: while Zn and Se are needed for a healthy prostate, Cd shows multiple toxic and carcinogenic effects. Excessive accumulation of Fe induces the production of highly reactive hydroxyl radical species, which may play a role in cancer etiopathogenesis. To assess whether the levels of these metals in the FFPE prostate tissue represent their original content, we compared their levels with those in the fresh tissue (on dry weight basis) in samples obtained from 15 patients. We found that in FFPE tissue, the recoveries of Se, Fe, Cd and Zn were progressively decreased, 97??11% (r=0.88), 82??22% (r=0.86), 59??23% (r=0.69) and 24??11% (r=0.38), respectively. Thus, the use of correction factors, determined as k=0.16 for Se, k=0.20 for Fe, k=0.27 for Cd and k=0.67 for Zn, is required to estimate the retrospective levels of these elements in the parental non-processed fresh (wet) prostate tissue. The technique used in this study enables the analysis of archival FFPE prostate tissue for the concentrations of Fe, Zn, Se and Cd to study association between the levels of these metals and prostate disease. ?? 2008.
Vidlar, Ales; Vostalova, Jitka; Ulrichova, Jitka; Student, Vladimir; Stejskal, David; Reichenbach, Richard; Vrbkova, Jana; Ruzicka, Filip; Simanek, Vilim
2010-10-01
Lower urinary tract symptoms (LUTS) are a common condition in older men. The objective of the present study was to evaluate the efficacy and tolerability of cranberry (Vaccinium macrocarpon) powder in men at risk of prostate disease with LUTS, elevated prostate-specific antigen (PSA), negative prostate biopsy and clinically confirmed chronic non-bacterial prostatitis. Forty-two participants received either 1500 mg of the dried powdered cranberries per d for 6 months (cranberry group; n 21) or no cranberry treatment (control group; n 21). Physical examination, International Prostate Symptom Score, quality of life (QoL), five-item version of the International Index of Erectile Function (IIEF-5), basic clinical chemistry parameters, haematology, Se, testosterone, PSA (free and total), C-reactive protein (CRP), antioxidant status, transrectal ultrasound prostate volume, urinary flow rate, ultrasound-estimated post-void residual urine volume at baseline, and at 3 and 6 months, and urine ex vivo anti-adherence activity were determined in all subjects. In contrast to the control group, patients in the cranberry group had statistically significant improvement in International Prostate Symptom Score, QoL, urination parameters including voiding parameters (rate of urine flow, average flow, total volume and post-void residual urine volume), and lower total PSA level on day 180 of the study. There was no influence on blood testosterone or serum CRP levels. There was no statistically significant improvement in the control group. The results of the present trial are the first firm evidence that cranberries may ameliorate LUTS, independent of benign prostatic hyperplasia or C-reactive protein level.
Weikert, S; Baumunk, D; Stephan, C; Cash, H; Jahnke, K; Steiner, U; Werthemann, P; Kempkensteffen, C; Magheli, A; Hinz, S; Jagota, A; Reichelt, U; Busch, J; Klopf, C; Miller, K; Schostak, M
2011-09-01
The introduction of prostate cancer treatment centers according to the criteria of the German Cancer Society ("Deutsche Krebsgesellschaft", DKG) aims at improving the quality of care for patients with prostate cancer. Systematic analyses of the effects and costs are lacking as yet. Three years after certification of the Interdisciplinary Prostate Cancer Center at the Charité Hospital Berlin we observed a decrease in the rate of positive surgical margins (tumor stage pT2), but other parameters of treatment quality including patient satisfaction remained unchanged. A survey among urologists of the region showed a high acceptance of prostate cancer centers in general. The majority of participating urologists appreciated the work of the Charité center, in particular the treatment recommendations given by the center were mostly followed and the majority of urologists regularly use educational activities of the center. However, only 30% of the participating urologists confirmed short-term improvements in the quality of patient care. Yearly additional costs for the Charité prostate cancer center are estimated at 205,000 euro (precertification phase and certification) and 138,000 euro (monitoring phase), despite the initial drop in mean treatment costs per case (radical prostatectomy). The introduction of prostate cancer treatment centers certified by the DKG is cost intensive, increases in treatment efficiency notwithstanding. Short-term improvements in quality of care cannot be unequivocally demonstrated. Prostate cancer centers serve an important role in counseling and medical education and may thus help disseminate evidence-based treatment strategies.
Optimal estimates of the diffusion coefficient of a single Brownian trajectory.
Boyer, Denis; Dean, David S; Mejía-Monasterio, Carlos; Oshanin, Gleb
2012-03-01
Modern developments in microscopy and image processing are revolutionizing areas of physics, chemistry, and biology as nanoscale objects can be tracked with unprecedented accuracy. The goal of single-particle tracking is to determine the interaction between the particle and its environment. The price paid for having a direct visualization of a single particle is a consequent lack of statistics. Here we address the optimal way to extract diffusion constants from single trajectories for pure Brownian motion. It is shown that the maximum likelihood estimator is much more efficient than the commonly used least-squares estimate. Furthermore, we investigate the effect of disorder on the distribution of estimated diffusion constants and show that it increases the probability of observing estimates much smaller than the true (average) value.
Fractional dynamics using an ensemble of classical trajectories
NASA Astrophysics Data System (ADS)
Sun, Zhaopeng; Dong, Hao; Zheng, Yujun
2018-01-01
A trajectory-based formulation for fractional dynamics is presented and the trajectories are generated deterministically. In this theoretical framework, we derive a new class of estimators in terms of confluent hypergeometric function (F11) to represent the Riesz fractional derivative. Using this method, the simulation of free and confined Lévy flight are in excellent agreement with the exact numerical and analytical results. In addition, the barrier crossing in a bistable potential driven by Lévy noise of index α is investigated. In phase space, the behavior of trajectories reveal the feature of Lévy flight in a better perspective.
Circumcision and prostate cancer: a population-based case-control study in Montréal, Canada
Spence, Andrea R; Rousseau, Marie-Claude; Karakiewicz, Pierre I; Parent, Marie-Élise
2014-01-01
Objectives To investigate the possible association between circumcision and prostate cancer risk, to examine whether age at circumcision influences prostate cancer risk, and to determine whether race modifies the circumcision–prostate cancer relationship. Subjects and Methods PROtEuS (Prostate Cancer and Environment Study), a population-based case-control study set amongst the mainly French-speaking population in Montréal, Canada, was used to address study objectives. The study included 1590 pathologically confirmed prostate cancer cases diagnosed in a Montréal French hospital between 2005 and 2009, and 1618 population controls ascertained from the French electoral list, frequency-matched to cases by age. In-person interviews elicited information on sociodemographic, lifestyle and environmental factors. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) between circumcision, age at circumcision and prostate cancer risk, adjusting for age, ancestry, family history of prostate cancer, prostate cancer screening history, education, and history of sexually transmitted infections. Results Circumcised men had a slightly lower risk, albeit not statistically significant, of developing prostate cancer than uncircumcised men (OR 0.89, 95% CI 0.76–1.04). Circumcision was found to be protective in men circumcised aged ≥36 years (OR 0.55, 95% CI 0.30–0.98). A weaker protective effect was seen among men circumcised within 1 year of birth (OR 0.86, 95% CI 0.72–1.04). The strongest protective effect of circumcision was recorded in Black men (OR 0.40, 95% CI 0.19–0.86, P-value for interaction 0.02) but no association was found with other ancestral groups. Conclusion Our findings provide novel evidence for a protective effect of circumcision against prostate cancer development, especially in those circumcised aged ≥36 years; although circumcision before the age of 1 year may also confer protection. Circumcision appeared to be protective only among Black men, a group that has the highest rate of disease. Further research into the differences in effect of circumcision on prostate cancer risk by ancestry is warranted, as is the influence of age at circumcision. PMID:24655933
NASA Astrophysics Data System (ADS)
St. Hill, Catherine; Lutfiyya, M. Nawal
2015-08-01
Prostate cancer is the second leading cause of cancer-related deaths in US males, yet much remains to be learned about the role of inflammation in its etiology. We hypothesized that preexisting exposure to chronic inflammatory conditions caused by infectious agents or inflammatory diseases increase the risk of prostate cancer. Using the 2009-2010 National Health and Nutrition Examination Survey, we examined the relationships between demographic variables, inflammation, infection, circulating plasma C-reactive protein (CRP), and the risk of occurrence of prostate cancer in US men over 18 years of age. Using IBM SPSS, we performed bivariate and logistic regression analyses using high CRP values as the dependent variable and five study covariates including prostate cancer status. From 2009 - 2010, an estimated 5,448,373 men reported having prostate cancer of which the majority were Caucasian (70.1%) and were aged 40 years and older (62.7%). Bivariate analyses demonstrated that high CRP was not associated with an increased risk of prostate cancer. Greater odds of having prostate cancer were revealed for men that had inflammation related to disease (OR = 1.029, CI 1.029-1.029) and those who were not taking drugs to control inflammation (OR = 1.330, CI 1.324-1.336). Men who did not have inflammation resulting from non-infectious diseases had greater odds of not having prostate cancer (OR = 1.031, CI 1.030-1.031). Logistic regression analysis yielded that men with the highest CRP values had greater odds of having higher household incomes and lower odds of having received higher education, being aged 40 years or older, being of a race or ethnicity different from other, and of having prostate cancer. Our results show that chronic inflammation of multiple etiologies is a risk factor for prostate cancer and that CRP is not associated with this increased risk. Further research is needed to elucidate the complex interactions between inflammation and prostate cancer.
Traffic Aware Strategic Aircrew Requests (TASAR)
NASA Technical Reports Server (NTRS)
Wing, David J.
2014-01-01
The Traffic Aware Strategic Aircrew Request (TASAR) concept offers onboard automation for the purpose of advising the pilot of traffic compatible trajectory changes that would be beneficial to the flight. A fast-time simulation study was conducted to assess the benefits of TASAR to Alaska Airlines. The simulation compares historical trajectories without TASAR to trajectories developed with TASAR and evaluated by controllers against their objectives. It was estimated that between 8,000 and 12,000 gallons of fuel and 900 to 1,300 minutes could be saved annually per aircraft. These savings were applied fleet-wide to produce an estimated annual cost savings to Alaska Airlines in excess of $5 million due to fuel, maintenance, and depreciation cost savings. Switching to a more wind-optimal trajectory was found to be the use case that generated the highest benefits out of the three TASAR use cases analyzed. Alaska TASAR requests peaked at four to eight requests per hour in high-altitude Seattle center sectors south of Seattle-Tacoma airport..
Annualized TASAR Benefits for Virgin America Operations
NASA Technical Reports Server (NTRS)
2014-01-01
The Traffic Aware Strategic Aircrew Request (TASAR) concept offers onboard automation for the purpose of advising the pilot of traffic compatible trajectory changes that would be beneficial to the flight. A fast-time simulation study was conducted to assess the benefits of TASAR to Virgin America. The simulation compares historical trajectories without TASAR to trajectories developed with TASAR and evaluated by controllers against their objectives. It was estimated that about 25,000 gallons of fuel and about 2,500 minutes could be saved annually per aircraft. These savings were applied fleet-wide to produce an estimated annual cost savings to Virgin America in excess of $5 million due to fuel, maintenance, and depreciation cost savings. Switching to a more wind-optimal trajectory was found to be the use case that generated the highest benefits out of the three TASAR use cases analyzed. Virgin America TASAR requests peaked at two to four requests per hour per sector in high-altitude Oakland and Salt Lake City center sectors east of San Francisco.
Marriage and parenthood in relation to obesogenic neighborhood trajectories: The CARDIA Study
Boone-Heinonen, Janne; Howard, Annie Green; Meyer, Katie; Lewis, Cora E.; Kiefe, Catarina I.; Laroche, Helena H.; Gunderson, Erica P.; Gordon-Larsen, Penny
2015-01-01
Marriage and parenthood are associated with weight gain and residential mobility. Little is known about how obesity-relevant environmental contexts differ according to family structure. We estimated trajectories of neighborhood poverty, population density, and density of fast food restaurants, supermarkets, and commercial and public physical activity facilities for adults from a biracial cohort (CARDIA, n=4,174, aged 25–50) over 13 years (1992–93 through 2005–06) using latent growth curve analysis. We estimated associations of marriage, parenthood, and race with the observed neighborhood trajectories. Married participants tended to live in neighborhoods with lower poverty, population density, and availability of all types of food and physical activity amenities. Parenthood was similarly but less consistently related to neighborhood characteristics. Marriage and parenthood were more strongly related to neighborhood trajectories in whites (versus blacks), who, in prior studies, exhibit weaker associations between neighborhood characteristics and health. Greater understanding of how interactive family and neighborhood environments contribute to healthy living is needed. PMID:26093081
Sullivan, Amanda L; Kohli, Nidhi; Farnsworth, Elyse M; Sadeh, Shanna; Jones, Leila
2017-09-01
Accurate estimation of developmental trajectories can inform instruction and intervention. We compared the fit of linear, quadratic, and piecewise mixed-effects models of reading development among students with learning disabilities relative to their typically developing peers. We drew an analytic sample of 1,990 students from the nationally representative Early Childhood Longitudinal Study-Kindergarten Cohort of 1998, using reading achievement scores from kindergarten through eighth grade to estimate three models of students' reading growth. The piecewise mixed-effects models provided the best functional form of the students' reading trajectories as indicated by model fit indices. Results showed slightly different trajectories between students with learning disabilities and without disabilities, with varying but divergent rates of growth throughout elementary grades, as well as an increasing gap over time. These results highlight the need for additional research on appropriate methods for modeling reading trajectories and the implications for students' response to instruction. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Treatment planning for prostate focal laser ablation in the face of needle placement uncertainty
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cepek, Jeremy, E-mail: jcepek@robarts.ca; Fenster, Aaron; Lindner, Uri
2014-01-15
Purpose: To study the effect of needle placement uncertainty on the expected probability of achieving complete focal target destruction in focal laser ablation (FLA) of prostate cancer. Methods: Using a simplified model of prostate cancer focal target, and focal laser ablation region shapes, Monte Carlo simulations of needle placement error were performed to estimate the probability of completely ablating a region of target tissue. Results: Graphs of the probability of complete focal target ablation are presented over clinically relevant ranges of focal target sizes and shapes, ablation region sizes, and levels of needle placement uncertainty. In addition, a table ismore » provided for estimating the maximum target size that is treatable. The results predict that targets whose length is at least 5 mm smaller than the diameter of each ablation region can be confidently ablated using, at most, four laser fibers if the standard deviation in each component of needle placement error is less than 3 mm. However, targets larger than this (i.e., near to or exceeding the diameter of each ablation region) require more careful planning. This process is facilitated by using the table provided. Conclusions: The probability of completely ablating a focal target using FLA is sensitive to the level of needle placement uncertainty, especially as the target length approaches and becomes greater than the diameter of ablated tissue that each individual laser fiber can achieve. The results of this work can be used to help determine individual patient eligibility for prostate FLA, to guide the planning of prostate FLA, and to quantify the clinical benefit of using advanced systems for accurate needle delivery for this treatment modality.« less
Bonilla, Carolina; Lewis, Sarah J; Rowlands, Mari-Anne; Gaunt, Tom R; Davey Smith, George; Gunnell, David; Palmer, Tom; Donovan, Jenny L; Hamdy, Freddie C; Neal, David E; Eeles, Rosalind; Easton, Doug; Kote-Jarai, Zsofia; Al Olama, Ali Amin; Benlloch, Sara; Muir, Kenneth; Giles, Graham G; Wiklund, Fredrik; Grönberg, Henrik; Haiman, Christopher A; Schleutker, Johanna; Nordestgaard, Børge G; Travis, Ruth C; Pashayan, Nora; Khaw, Kay-Tee; Stanford, Janet L; Blot, William J; Thibodeau, Stephen; Maier, Christiane; Kibel, Adam S; Cybulski, Cezary; Cannon-Albright, Lisa; Brenner, Hermann; Park, Jong; Kaneva, Radka; Batra, Jyotsna; Teixeira, Manuel R; Pandha, Hardev; Lathrop, Mark; Martin, Richard M; Holly, Jeff M P
2016-10-01
Circulating insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are associated with prostate cancer. Using genetic variants as instruments for IGF peptides, we investigated whether these associations are likely to be causal. We identified from the literature 56 single nucleotide polymorphisms (SNPs) in the IGF axis previously associated with biomarker levels (8 from a genome-wide association study [GWAS] and 48 in reported candidate genes). In ∼700 men without prostate cancer and two replication cohorts (N ∼ 900 and ∼9,000), we examined the properties of these SNPS as instrumental variables (IVs) for IGF-I, IGF-II, IGFBP-2 and IGFBP-3. Those confirmed as strong IVs were tested for association with prostate cancer risk, low (< 7) vs. high (≥ 7) Gleason grade, localised vs. advanced stage, and mortality, in 22,936 controls and 22,992 cases. IV analysis was used in an attempt to estimate the causal effect of circulating IGF peptides on prostate cancer. Published SNPs in the IGFBP1/IGFBP3 gene region, particularly rs11977526, were strong instruments for IGF-II and IGFBP-3, less so for IGF-I. Rs11977526 was associated with high (vs. low) Gleason grade (OR per IGF-II/IGFBP-3 level-raising allele 1.05; 95% CI: 1.00, 1.10). Using rs11977526 as an IV we estimated the causal effect of a one SD increase in IGF-II (∼265 ng/mL) on risk of high vs. low grade disease as 1.14 (95% CI: 1.00, 1.31). Because of the potential for pleiotropy of the genetic instruments, these findings can only causally implicate the IGF pathway in general, not any one specific biomarker. © 2016 UICC.
Optimization of PSA screening policies: a comparison of the patient and societal perspectives.
Zhang, Jingyu; Denton, Brian T; Balasubramanian, Hari; Shah, Nilay D; Inman, Brant A
2012-01-01
To estimate the benefit of PSA-based screening for prostate cancer from the patient and societal perspectives. A partially observable Markov decision process model was used to optimize PSA screening decisions. Age-specific prostate cancer incidence rates and the mortality rates from prostate cancer and competing causes were considered. The model trades off the potential benefit of early detection with the cost of screening and loss of patient quality of life due to screening and treatment. PSA testing and biopsy decisions are made based on the patient's probability of having prostate cancer. Probabilities are inferred based on the patient's complete PSA history using Bayesian updating. The results of all PSA tests and biopsies done in Olmsted County, Minnesota, from 1993 to 2005 (11,872 men and 50,589 PSA test results). Patients' perspective: to maximize expected quality-adjusted life years (QALYs); societal perspective: to maximize the expected monetary value based on societal willingness to pay for QALYs and the cost of PSA testing, prostate biopsies, and treatment. From the patient perspective, the optimal policy recommends stopping PSA testing and biopsy at age 76. From the societal perspective, the stopping age is 71. The expected incremental benefit of optimal screening over the traditional guideline of annual PSA screening with threshold 4.0 ng/mL for biopsy is estimated to be 0.165 QALYs per person from the patient perspective and 0.161 QALYs per person from the societal perspective. PSA screening based on traditional guidelines is found to be worse than no screening at all. PSA testing done with traditional guidelines underperforms and therefore underestimates the potential benefit of screening. Optimal screening guidelines differ significantly depending on the perspective of the decision maker.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shaffer, Richard, E-mail: rickyshaffer@yahoo.co.u; Department of Clinical Oncology, Imperial College London National Health Service Trust, London; Pickles, Tom
Purpose: Prior studies have derived low values of alpha-beta ratio (a/ss) for prostate cancer of approximately 1-2 Gy. These studies used poorly matched groups, differing definitions of biochemical failure, and insufficient follow-up. Methods and Materials: National Comprehensive Cancer Network low- or low-intermediate risk prostate cancer patients, treated with external beam radiotherapy or permanent prostate brachytherapy, were matched for prostate-specific antigen, Gleason score, T-stage, percentage of positive cores, androgen deprivation therapy, and era, yielding 118 patient pairs. The Phoenix definition of biochemical failure was used. The best-fitting value for a/ss was found for up to 90-month follow-up using maximum likelihood analysis,more » and the 95% confidence interval using the profile likelihood method. Linear quadratic formalism was applied with the radiobiological parameters of relative biological effectiveness = 1.0, potential doubling time = 45 days, and repair half-time = 1 hour. Bootstrap analysis was performed to estimate uncertainties in outcomes, and hence in a/ss. Sensitivity analysis was performed by varying the values of the radiobiological parameters to extreme values. Results: The value of a/ss best fitting the outcomes data was >30 Gy, with lower 95% confidence limit of 5.2 Gy. This was confirmed on bootstrap analysis. Varying parameters to extreme values still yielded best-fit a/ss of >30 Gy, although the lower 95% confidence interval limit was reduced to 0.6 Gy. Conclusions: Using carefully matched groups, long follow-up, the Phoenix definition of biochemical failure, and well-established statistical methods, the best estimate of a/ss for low and low-tier intermediate-risk prostate cancer is likely to be higher than that of normal tissues, although a low value cannot be excluded.« less
Cancer survival in Cali, Colombia: A population-based study, 1995-2004
García, Luz Stella; Collazos, Paola Andrea
2014-01-01
Background: There is limited information on population-based cancer survival data in Latin America. Objetive: To obtain estimates of survival for some cancers recognized as a public health priority in Colombia using data from the Cancer Registry of Cali for 1995-2004. Methods: All cancer cases for residents of Cali were included for the following sites: breast (3,984), cervix uteri (2,469), prostate (3,999), stomach (3,442) and lung (2,170). Five-year relative survival estimates were calculated using the approach described by Estève. Results: Five-year relative survival was 79% in patients with prostate cancer and 68% and 60% in women with breast or cervix uteri cancer, respectively. The cure fraction was close to zero in subjects with lung cancer and less than 10% in those with stomach cancer. The probability of dying from breast or prostate cancer in people in the lower socio-economic strata (SES) was 1.8 and 2.6 times, respectively, when compared to upper SES, p <0.001. Excess mortality associated with cancer was independent of age in prostate or breast cancer. After adjusting for age, sex and SES, the risk of dying from breast, cervix uteri, prostate and lung cancer during the 2000-2004 period decreased 19%, 13%, 48% and 16%, respectively, when compared with the period of 1995-1999. There was no change in the prognosis for patients with stomach cancer. Conclusions: Survival for some kinds of cancer improved through the 1995-2004 period, however health care programs for cancer patients in Cali are inequitable. People from lower SES are the most vulnerable and the least likely to survive. PMID:25386036
Antioxidant effects of gamma-oryzanol on human prostate cancer cells.
Klongpityapong, Papavadee; Supabphol, Roongtawan; Supabphol, Athikom
2013-01-01
To assess the antioxidant effects of gamma-oryzanol on human prostate cancer cells. Cytotoxic activity of gamma-oryzanol on human DU145 and PC3 prostate cancer cells was determined by proliferation assay using 3-(4, 5-dimethylthiazol, 2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) reagent. mRNA levels of genes involved in the intracellular antioxidant system, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GSR) were determined by reverse transcription-polymerase chain reaction (RT-PCR). Cancer cell lysates were used to measure lipid peroxidation using thiobarbituric acid reactive substance (TBARS). Glutathione contents of the cell lysates were estimated by the reaction between sulfhydryl group of 5, 5'-dithio (bis) nitrobenzoic acid (DTNB) to produce a yellow- color of 5-thio-2-nitrobenzoic acid using colorimetric assay. Catalase activity was also analysed by examining peroxidative function. Protein concentration was estimated by Bradford's assay. All concentrations of gamma-oryzanol, 0.1-2.0mg/ml, significantly inhibited cell growth in a dose- and time-dependent fashion in both prostate cancer cell lines, DU145 and PC3. Gene expression of catalase in DU145 and PC3 exposed to gamma-orizanol at 0.5mg/ml for 14 days was down regulated, while mRNA of GPX was also down regulated in PC3. The MDA and glutathione levels including catalase activity in the cell lysates of DU145 and PC3 treated with gamma-oryzanol 0.1 and 0.5mg/ml were generally decreased. This study highlighted effects of gamma-oryzanol via the down-regulation of antioxidant genes, catalase and GPX, not cytotoxic roles. This might be interesting for adjuvant chemotherapy to make prostate cancer cells more sensitive to free radicals. It might be useful for the reduction of cytotoxic agents and cancer chemoprevention.
Longitudinal regret after treatment for low- and intermediate-risk prostate cancer.
Hurwitz, Lauren M; Cullen, Jennifer; Kim, Daniel J; Elsamanoudi, Sally; Hudak, Jane; Colston, Maryellen; Travis, Judith; Kuo, Huai-Ching; Rice, Kevin R; Porter, Christopher R; Rosner, Inger L
2017-11-01
Prostate cancer patients diagnosed with low- and intermediate-risk disease have several treatment options. Decisional regret after treatment is a concern, especially when poor oncologic outcomes or declines in health-related quality of life (HRQoL) occur. This study assessed determinants of longitudinal decisional regret in prostate cancer patients attending a multidisciplinary clinic and treated with radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy (BT), or active surveillance (AS). Patients newly diagnosed with prostate cancer at the Walter Reed National Military Medical Center who attended a multidisciplinary clinic were enrolled into a prospective study from 2006 to 2014. The Decision Regret Scale was administered at 6, 12, 24, and 36 months posttreatment. HRQoL was also assessed at regular intervals using the Expanded Prostate Cancer Index Composite and 36-item RAND Medical Outcomes Study Short Form questionnaires. Adjusted probabilities of reporting regret were estimated via multivariable logistic regression fitted with generalized estimating equations. A total of 652 patients met the inclusion criteria (395 RP, 141 EBRT, 41 BT, 75 AS). Decisional regret was consistently low after all of these treatments. In multivariable models, only African American race (odds ratio, 1.67; 95% confidence interval, 1.12-2.47) was associated with greater regret across time. Age and control preference were marginally associated with regret. Regret scores were similar between RP patients who did and did not experience biochemical recurrence. Declines in HRQoL were weakly correlated with greater decisional regret. In the context of a multidisciplinary clinic, decisional regret did not differ significantly between treatment groups but was greater in African Americans and those reporting poorer HRQoL. Cancer 2017;123:4252-4258. © 2017 American Cancer Society. © 2017 American Cancer Society.
Pathmanathan, Angela U; van As, Nicholas J; Kerkmeijer, Linda G W; Christodouleas, John; Lawton, Colleen A F; Vesprini, Danny; van der Heide, Uulke A; Frank, Steven J; Nill, Simeon; Oelfke, Uwe; van Herk, Marcel; Li, X Allen; Mittauer, Kathryn; Ritter, Mark; Choudhury, Ananya; Tree, Alison C
2018-02-01
Radiation therapy to the prostate involves increasingly sophisticated delivery techniques and changing fractionation schedules. With a low estimated α/β ratio, a larger dose per fraction would be beneficial, with moderate fractionation schedules rapidly becoming a standard of care. The integration of a magnetic resonance imaging (MRI) scanner and linear accelerator allows for accurate soft tissue tracking with the capacity to replan for the anatomy of the day. Extreme hypofractionation schedules become a possibility using the potentially automated steps of autosegmentation, MRI-only workflow, and real-time adaptive planning. The present report reviews the steps involved in hypofractionated adaptive MRI-guided prostate radiation therapy and addresses the challenges for implementation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Howard, David H.; Tangka, Florence K.; Guy, Gery P.; Ekwueme, Donatus U.; Lipscomb, Joseph
2016-01-01
In 2008 the US Preventive Services Task Force recommended against screening men ages 75 and older for prostate cancer. Using Medicare Current Beneficiary Survey Access to Care files and linked claims, we compared trends in prostate-specific antigen (PSA) testing rates between men ages 75 and older and men ages 65–74. We estimate that the revised recommendation led to a 7.9-percentage-point decline in annual PSA testing rates over two years among men ages 75 and older. Although 42 percent of men in this age group continue to receive PSA tests, our results highlight the potential of guidelines with negative recommendations to reduce the use of low-value medical care. PMID:23459740
A Robot Trajectory Optimization Approach for Thermal Barrier Coatings Used for Free-Form Components
NASA Astrophysics Data System (ADS)
Cai, Zhenhua; Qi, Beichun; Tao, Chongyuan; Luo, Jie; Chen, Yuepeng; Xie, Changjun
2017-10-01
This paper is concerned with a robot trajectory optimization approach for thermal barrier coatings. As the requirements of high reproducibility of complex workpieces increase, an optimal thermal spraying trajectory should not only guarantee an accurate control of spray parameters defined by users (e.g., scanning speed, spray distance, scanning step, etc.) to achieve coating thickness homogeneity but also help to homogenize the heat transfer distribution on the coating surface. A mesh-based trajectory generation approach is introduced in this work to generate path curves on a free-form component. Then, two types of meander trajectories are generated by performing a different connection method. Additionally, this paper presents a research approach for introducing the heat transfer analysis into the trajectory planning process. Combining heat transfer analysis with trajectory planning overcomes the defects of traditional trajectory planning methods (e.g., local over-heating), which helps form the uniform temperature field by optimizing the time sequence of path curves. The influence of two different robot trajectories on the process of heat transfer is estimated by coupled FEM models which demonstrates the effectiveness of the presented optimization approach.
On Integral Invariants for Effective 3-D Motion Trajectory Matching and Recognition.
Shao, Zhanpeng; Li, Youfu
2016-02-01
Motion trajectories tracked from the motions of human, robots, and moving objects can provide an important clue for motion analysis, classification, and recognition. This paper defines some new integral invariants for a 3-D motion trajectory. Based on two typical kernel functions, we design two integral invariants, the distance and area integral invariants. The area integral invariants are estimated based on the blurred segment of noisy discrete curve to avoid the computation of high-order derivatives. Such integral invariants for a motion trajectory enjoy some desirable properties, such as computational locality, uniqueness of representation, and noise insensitivity. Moreover, our formulation allows the analysis of motion trajectories at a range of scales by varying the scale of kernel function. The features of motion trajectories can thus be perceived at multiscale levels in a coarse-to-fine manner. Finally, we define a distance function to measure the trajectory similarity to find similar trajectories. Through the experiments, we examine the robustness and effectiveness of the proposed integral invariants and find that they can capture the motion cues in trajectory matching and sign recognition satisfactorily.
Ju-Kun, Song; Yuan, Dong-Bo; Rao, Hao-Fu; Chen, Tian-Fei; Luan, Bo-Shi; Xu, Xiao-Ming; Jiang, Fu-Neng; Zhong, Wei-De; Zhu, Jian-Guo
2016-02-01
Several observational studies on the association between Cd exposure and risk of prostate cancer have yielded inconsistent results. To address this issue, we conducted a meta-analysis to evaluate the correlation between Cd exposure and risk of prostate cancer.Relevant studies in PubMed and Embase databases were retrieved until October 2015. We compared the highest and lowest meta-analyses to quantitatively evaluate the relationship between Cd exposure and risk of prostate cancer. Summary estimates were obtained using a random-effects model.In the general population, high Cd exposure was not associated with increased prostate cancer (OR 1.21; 95% CI 0.91-1.64), whereas the combined standardized mortality ratio of the association between Cd exposure and risk of prostate cancer was 1.66 (95% CI 1.10-2.50) in populations exposed to occupational Cd. In addition, high D-Cd intake (OR 1.07; 95% CI 0.96-1.20) and U-Cd concentration (OR 0.86; 95% CI 0.48-1.55) among the general population was not related to the increased risk of prostate cancer. In the dose analysis, the summary relative risk was 1.07 (95% CI 0.73-1.57) for each 0.5 μg/g creatinine increase in U-Cd and 1.02 (95% CI 0.99-1.06) for each 10 μg/day increase of dietary Cd intake. However, compared with nonoccupational exposure, high occupational Cd exposure may be associated with the increased risk of prostate cancer.This meta-analysis suggests high Cd exposure as a risk factor for prostate cancer in occupational rather than nonoccupational populations. However, these results should be carefully interpreted because of the significant heterogeneity among studies. Additional large-scale and high-quality prospective studies are needed to confirm the association between Cd exposure and risk of prostate cancer.
Association Between Cd Exposure and Risk of Prostate Cancer
Ju-Kun, Song; Yuan, Dong-Bo; Rao, Hao-Fu; Chen, Tian-Fei; Luan, Bo-Shi; Xu, Xiao-Ming; Jiang, Fu-Neng; Zhong, Wei-De; Zhu, Jian-Guo
2016-01-01
Abstract Several observational studies on the association between Cd exposure and risk of prostate cancer have yielded inconsistent results. To address this issue, we conducted a meta-analysis to evaluate the correlation between Cd exposure and risk of prostate cancer. Relevant studies in PubMed and Embase databases were retrieved until October 2015. We compared the highest and lowest meta-analyses to quantitatively evaluate the relationship between Cd exposure and risk of prostate cancer. Summary estimates were obtained using a random-effects model. In the general population, high Cd exposure was not associated with increased prostate cancer (OR 1.21; 95% CI 0.91–1.64), whereas the combined standardized mortality ratio of the association between Cd exposure and risk of prostate cancer was 1.66 (95% CI 1.10–2.50) in populations exposed to occupational Cd. In addition, high D-Cd intake (OR 1.07; 95% CI 0.96–1.20) and U-Cd concentration (OR 0.86; 95% CI 0.48–1.55) among the general population was not related to the increased risk of prostate cancer. In the dose analysis, the summary relative risk was 1.07 (95% CI 0.73–1.57) for each 0.5 μg/g creatinine increase in U-Cd and 1.02 (95% CI 0.99–1.06) for each 10 μg/day increase of dietary Cd intake. However, compared with nonoccupational exposure, high occupational Cd exposure may be associated with the increased risk of prostate cancer. This meta-analysis suggests high Cd exposure as a risk factor for prostate cancer in occupational rather than nonoccupational populations. However, these results should be carefully interpreted because of the significant heterogeneity among studies. Additional large-scale and high-quality prospective studies are needed to confirm the association between Cd exposure and risk of prostate cancer. PMID:26871808
A Contemporary Prostate Biopsy Risk Calculator Based on Multiple Heterogeneous Cohorts.
Ankerst, Donna P; Straubinger, Johanna; Selig, Katharina; Guerrios, Lourdes; De Hoedt, Amanda; Hernandez, Javier; Liss, Michael A; Leach, Robin J; Freedland, Stephen J; Kattan, Michael W; Nam, Robert; Haese, Alexander; Montorsi, Francesco; Boorjian, Stephen A; Cooperberg, Matthew R; Poyet, Cedric; Vertosick, Emily; Vickers, Andrew J
2018-05-16
Prostate cancer prediction tools provide quantitative guidance for doctor-patient decision-making regarding biopsy. The widely used online Prostate Cancer Prevention Trial Risk Calculator (PCPTRC) utilized data from the 1990s based on six-core biopsies and outdated grading systems. We prospectively gathered data from men undergoing prostate biopsy in multiple diverse North American and European institutions participating in the Prostate Biopsy Collaborative Group (PBCG) in order to build a state-of-the-art risk prediction tool. We obtained data from 15 611 men undergoing 16 369 prostate biopsies during 2006-2017 at eight North American institutions for model-building and three European institutions for validation. We used multinomial logistic regression to estimate the risks of high-grade prostate cancer (Gleason score ≥7) on biopsy based on clinical characteristics, including age, prostate-specific antigen, digital rectal exam, African ancestry, first-degree family history, and prior negative biopsy. We compared the PBCG model to the PCPTRC using internal cross-validation and external validation on the European cohorts. Cross-validation on the North American cohorts (5992 biopsies) yielded the PBCG model area under the receiver operating characteristic curve (AUC) as 75.5% (95% confidence interval: 74.2-76.8), a small improvement over the AUC of 72.3% (70.9-73.7) for the PCPTRC (p<0.0001). However, calibration and clinical net benefit were far superior for the PBCG model. Using a risk threshold of 10%, clinical use of the PBCG model would lead to the equivalent of 25 fewer biopsies per 1000 patients without missing any high-grade cancers. Results were similar on external validation on 10 377 European biopsies. The PBCG model should be used in place of the PCPTRC for prediction of prostate biopsy outcome. A contemporary risk tool for outcomes on prostate biopsy based on the routine clinical risk factors is now available for informed decision-making. Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Benign Prostatic Hyperplasia and the Risk of Prostate Cancer and Bladder Cancer
Dai, Xiaoyu; Fang, Xiangming; Ma, Ying; Xianyu, Jianbo
2016-01-01
Abstract Benign prostatic hyperplasia (BPH) has been suggested to be a risk factor for certain urologic cancers, but the current evidence is inconsistent. The aim of this study was to investigate the association between BPH and urologic cancers. MEDLINE, EMBASE, Cochrane Library, and Web of Science were searched for potential eligible studies. We included case-control studies or cohort studies, which evaluated the association between BPH and urologic cancers (including prostate cancer, bladder cancer, kidney cancer, testicular cancer, or penile cancer). Overall effect estimates were calculated using the DerSimonian–Laird method for a random-effects model. Summary effect-size was calculated as risk ratio (RR), together with the 95% confidence interval (CI). This systematic review included 16 case-control studies and 10 cohort studies evaluating the association of BPH and prostate or bladder cancer; we did not identify any study about other urologic cancers. Meta-analyses demonstrated that BPH was associated with an increased incidence of prostate cancer (case-control study: RR = 3.93, 95% CI = 2.18–7.08; cohort-study: RR = 1.41, 95% CI = 1.00–1.99) and bladder cancer (case-control study: RR = 2.50, 95% CI = 1.63–3.84; cohort-study: RR = 1.58, 95% CI = 1.28–1.95). Subgroup analysis by ethnicity suggested that the association between BPH and prostate cancer was much stronger in Asians (RR = 6.09, 95% CI = 2.96–12.54) than in Caucasians (RR = 1.54, 95% CI = 1.19–2.01). Egger's tests indicated low risk of publication bias (prostate cancer: P = 0.11; bladder cancer: P = 0.95). BPH is associated with an increased risk of prostate cancer and bladder cancer. The risk of prostate cancer is particularly high in Asian BPH patients. Given the limitations of included studies, additional prospective studies with strict design are needed to confirm our findings. PMID:27149447
Abhyankar, Nikita; Hoskins, Kent F; Abern, Michael R; Calip, Gregory S
2017-09-25
Current evidence on risk of prostate cancer following a diagnosis of male breast cancer is limited and guidance for screening in this potentially higher-risk population remainsunclear. Our objective was to quantify prostate cancer risk in men diagnosed with breast cancer. We identified men diagnosed with first primary breast cancer between 1988 and 2012 using the Surveillance, Epidemiology and End Results Program registry databases. Men were followed for occurrence of a second primary prostate cancer and secondary outcomes of cancer-specific and overall survival. Stratified analyses were performed by age, breast cancer stage, race, and breast cancer hormone receptor status. Excess risk per 10,000 person-years and standardized incidence ratios (SIR) with 95% confidence intervals (95% CI) were calculated. We used multivaraible Cox proportional hazard models to estimate hazard ratios (HR) and 95% CI for characteristics associated with secondary prostate cancer and survival. From a cohort of 5753 men with breast cancer with median follow up of 4.3 years, we identified 250 cases of second primary prostate cancer. Overall, the incidence of second primary prostate cancer was modestly greater than expected (SIR = 1.12, 95% CI 0.93-1.33), although not statistically significant. Stratified analyses demonstrated associations for men ages 65-74 at the time of breast cancer diagnosis (SIR = 1.34, 95%CI 1.01-1.73), hormone receptor-positive breast cancer (SIR = 1.23, 95%CI 1.11-1.39) or AJCC stage I breast cancer (SIR = 1.36, 95%CI 1.04-1.75) and second primary prostate cancer diagnosis. The incidence of prostate cancer in men with history of breast cancer is similar to the general population. Men with favorable characteristics of their breast cancer were more likely to develop prostate cancer, possibly due to a lower competing risk of breast cancer mortality.
Perez-Cornago, Aurora; Travis, Ruth C; Appleby, Paul N; Tsilidis, Konstantinos K; Tjønneland, Anne; Olsen, Anja; Overvad, Kim; Katzke, Verena; Kühn, Tilman; Trichopoulou, Antonia; Peppa, Eleni; Kritikou, Maria; Sieri, Sabina; Palli, Domenico; Sacerdote, Carlotta; Tumino, Rosario; Bueno-de-Mesquita, H B As; Agudo, Antonio; Larrañaga, Nerea; Molina-Portillo, Elena; Ardanaz, Eva; Chirlaque, Maria-Dolores; Lasheras, Cristina; Stattin, Pär; Wennberg, Maria; Drake, Isabel; Malm, Johan; Schmidt, Julie A; Khaw, Kay-Tee; Gunter, Marc; Freisling, Heinz; Huybrechts, Inge; Aune, Dagfinn; Cross, Amanda J; Riboli, Elio; Key, Timothy J
2017-07-15
Several dietary factors have been studied in relation to prostate cancer; however, most studies have not reported on subtypes of fruit and vegetables or tumor characteristics, and results obtained so far are inconclusive. This study aimed to examine the prospective association of total and subtypes of fruit and vegetable intake with the incidence of prostate cancer overall, by grade and stage of disease, and prostate cancer death. Lifestyle information for 142,239 men participating in the European Prospective Investigation into Cancer and Nutrition from 8 European countries was collected at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). After an average follow-up time of 13.9 years, 7,036 prostate cancer cases were identified. Compared with the lowest fifth, those in the highest fifth of total fruit intake had a significantly reduced prostate cancer risk (HR = 0.91; 95% CI = 0.83-0.99; p-trend = 0.01). No associations between fruit subtypes and prostate cancer risk were observed, except for citrus fruits, where a significant trend was found (HR = 0.94; 95% CI = 0.86-1.02; p-trend = 0.01). No associations between total and subtypes of vegetables and prostate cancer risk were observed. We found no evidence of heterogeneity in these associations by tumor grade and stage, with the exception of significant heterogeneity by tumor grade (p heterogeneity <0.001) for leafy vegetables. No significant associations with prostate cancer death were observed. The main finding of this prospective study was that a higher fruit intake was associated with a small reduction in prostate cancer risk. Whether this association is causal remains unclear. © 2017 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.
Body mass index in relation to serum prostate-specific antigen levels and prostate cancer risk.
Bonn, Stephanie E; Sjölander, Arvid; Tillander, Annika; Wiklund, Fredrik; Grönberg, Henrik; Bälter, Katarina
2016-07-01
High Body mass index (BMI) has been directly associated with risk of aggressive or fatal prostate cancer. One possible explanation may be an effect of BMI on serum levels of prostate-specific antigen (PSA). To study the association between BMI and serum PSA as well as prostate cancer risk, a large cohort of men without prostate cancer at baseline was followed prospectively for prostate cancer diagnoses until 2015. Serum PSA and BMI were assessed among 15,827 men at baseline in 2010-2012. During follow-up, 735 men were diagnosed with prostate cancer with 282 (38.4%) classified as high-grade cancers. Multivariable linear regression models and natural cubic linear regression splines were fitted for analyses of BMI and log-PSA. For risk analysis, Cox proportional hazards regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) and natural cubic Cox regression splines producing standardized cancer-free probabilities were fitted. Results showed that baseline Serum PSA decreased by 1.6% (95% CI: -2.1 to -1.1) with every one unit increase in BMI. Statistically significant decreases of 3.7, 11.7 and 32.3% were seen for increasing BMI-categories of 25 < 30, 30 < 35 and ≥35 kg/m(2), respectively, compared to the reference (18.5 < 25 kg/m(2)). No statistically significant associations were seen between BMI and prostate cancer risk although results were indicative of a positive association to incidence rates of high-grade disease and an inverse association to incidence of low-grade disease. However, findings regarding risk are limited by the short follow-up time. In conclusion, BMI was inversely associated to PSA-levels. BMI should be taken into consideration when referring men to a prostate biopsy based on serum PSA-levels. © 2016 UICC.
Farag, Adam; Peterson, Justin Charles; Szekeres, Trevor; Bauman, Glenn; Chin, Joseph; Romagnoli, Cesare; Bartha, Robert; Scholl, Timothy J
2015-08-01
To develop and optimize radiofrequency (RF) hardware for the detection of endogenous sodium ((23) Na) by 3.0 Tesla (T) MRI in the human prostate. A transmit-only receive-only (TORO) RF system of resonators consisting of an unshielded, asymmetric, quadrature birdcage (transmit), and an endorectal (ER), linear, surface (receive) coil were developed and tested on a 3T MRI scanner. Two different ER receivers were constructed; a single-tuned ((23) Na) and a dual-tuned ((1) H/(23) Na). Both receivers were evaluated by the measurements of signal-to-noise ratio (SNR) and B1 homogeneity. For tissue sodium concentration (TSC) quantification, vials containing known sodium concentrations were incorporated into the ER. The system was used to measure the prostate TSC of three men (age 55 ± 5 years) with biopsy-proven prostate cancer. B1 field inhomogeneity of the asymmetric transmitter was estimated to be less than 5%. The mean SNR measured in a region of interest within the prostate using the single-tuned ER coil was 54.0 ± 4.6. The mean TSC in the central gland was 60.2 ± 5.7 mmol/L and in the peripheral gland was 70.5 ± 9.0 mmol/L. A TORO system was developed and optimized for (23) Na MRI of the human prostate which showed good sensitivity throughout the prostate for quantitative measurement of TSC. © 2014 Wiley Periodicals, Inc.
The incidence of prostate cancer in Iran: a systematic review and meta-analysis.
Hassanipour, Soheil; Fathalipour, Mohammad; Salehiniya, Hamid
2018-06-01
Prostate cancer is one of the most common cancers among men. There are various estimates of prostate cancer incidence from different geographical areas in Iran. In addition, no systematic reviews are available regarding the incidence rate of prostate cancer in Iran. Therefore, the present systematic review aimed to address this epidemiological gap. This systematic review was performed based on the preferred reporting items for systematic reviews and meta-analyses in July 2017. In doing so, the researchers searched Medline/PubMed, Scopus, Embase, ScienceDirect, and Google Scholar for international articles and four Iranian databases (Scientific Information Database, MagIran, IranMedex, and IranDoc) for Persian articles. A total of 274 titles were retrieved in the initial search of the databases. Further refinement and screening of the retrieved studies produced a total of 21 studies. Based on the random-effect model, the age-standardized rate of prostate cancer was 9.11 and 95% confidence interval was 8.19-10.04. Besides, the results of Cochran's test indicated the heterogeneity of the studies (Q = 1457.8, df = 46.0, I 2 = 96.8%, P < 0.001). The incidence of prostate cancer was lower in Iran than in the other parts of the world. Yet, establishing cancer registries covering a broader perspective of the population and conducting further studies are required to map out the exact incidence rate and trend of prostate cancer in Iran.
Clinical development of holmium:YAG laser prostatectomy
NASA Astrophysics Data System (ADS)
Kabalin, John N.
1996-05-01
Holmium:YAG (Ho:YAG) laser vaporization and resection of the prostate offers advantages in immediate tissue removal compared to the Neodymium:YAG (Nd:YAG) laser. Ongoing development of appropriate operative techniques and Ho:YAG laser delivery systems suitable for endoscopic prostate surgery, including side-firing optical delivery fibers, have facilitated this approach. We performed Ho:YAG laser prostatectomy in 20 human subjects, including 2 men treated immediately prior to radical prostatectomy to assess Ho:YAG laser effects in the prostate. A total of 18 men were treated in an initial clinical trial of Ho:YAG prostatectomy. Estimated excess hyperplastic prostate tissue averaged 24 g (range 5 - 50 g). A mean of 129 kj Ho:YAG laser energy was delivered, combined with a mean of 11 kj Nd:YAG energy to provide supplemental coagulation for hemostasis. We have observed no significant perioperative or late complications. No significant intraoperative changes in hematocrit or serum electrolytes were documented. In addition to providing acute removal of obstructing prostate tissue, Ho:YAG laser resection allowed tissue specimen to be obtained for histologic examination. A total of 16 of 18 patients (90%) underwent successful removal of their urinary catheter and voiding trial within 24 hours following surgery. Immediate improvement in voiding, comparable to classic transurethral electrocautery resection of the prostate (TURP), was reported by all patients. Ho:YAG laser resection of the prostate appears to be a viable surgical technique associated with minimal morbidity and immediate improvement in voiding.
Zhou, Cindy Ke; Young, Denise; Yeboah, Edward D; Coburn, Sally B; Tettey, Yao; Biritwum, Richard B; Adjei, Andrew A; Tay, Evelyn; Niwa, Shelley; Truelove, Ann; Welsh, Judith; Mensah, James E; Hoover, Robert N; Sesterhenn, Isabell A; Hsing, Ann W; Srivastava, Shiv; Cook, Michael B
2017-01-01
Abstract The prevalence of fusions of the transmembrane protease, serine 2, gene (TMPRSS2) with the erythroblast transformation-specific–related gene (ERG), or TMPRSS2:ERG, in prostate cancer varies by race. However, such somatic aberration and its association with prognostic factors have neither been studied in a West African population nor been systematically reviewed in the context of racial differences. We used immunohistochemistry to assess oncoprotein encoded by the ERG gene as the established surrogate of ERG fusion genes among 262 prostate cancer biopsies from the Ghana Prostate Study (2004–2006). Poisson regression with robust variance estimation provided prevalence ratios and 95% confidence intervals of ERG expression in relation to patient characteristics. We found that 47 of 262 (18%) prostate cancers were ERG-positive, and being negative for ERG staining was associated with higher Gleason score. We further conducted a systematic review and meta-analysis of TMPRSS2:ERG fusions in relation to race, Gleason score, and tumor stage, combining results from Ghana with 40 additional studies. Meta-analysis showed the prevalence of TMPRSS2:ERG fusions in prostate cancer to be highest in men of European descent (49%), followed by men of Asian (27%) and then African (25%) descent. The lower prevalence of TMPRSS2:ERG fusions in men of African descent implies that alternative genomic mechanisms might explain the disproportionately high prostate cancer burden in such populations. PMID:28633309
Etzioni, Ruth; Gulati, Roman; Cooperberg, Matt R; Penson, David M; Weiss, Noel S; Thompson, Ian M
2013-04-01
The US Preventive Services Task Force recently recommended against prostate-specific antigen screening for prostate cancer based primarily on evidence from the European Randomized Study of Screening for Prostate Cancer (ERSPC) and the US Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. : To examine limitations of basing screening policy on evidence from screening trials. We reviewed published modeling studies that examined population and trial data. The studies (1) project the roles of screening and changes in primary treatment in the US mortality decline; (2) extrapolate the ERSPC mortality reduction to the long-term US setting; (3) estimate overdiagnosis based on US incidence trends; and (4) quantify the impact of control arm screening on PLCO mortality results. Screening plausibly explains 45% and changes in primary treatment can explain 33% of the US prostate cancer mortality decline. Extrapolating the ERSPC results to the long-term US setting implies an absolute mortality reduction at least 5 times greater than that observed in the trial. Approximately 28% of screen-detected cases are overdiagnosed in the United States versus 58% of screen-detected cases suggested by the ERSPC results. Control arm screening can explain the null result in the PLCO trial. Modeling studies indicate that population trends and trial results extended to the long-term population setting are consistent with greater benefit of prostate-specific antigen screening-and more favorable harm-benefit tradeoffs-than has been suggested by empirical trial evidence.
Research in navigation and optimization for space trajectories
NASA Technical Reports Server (NTRS)
Pines, S.; Kelley, H. J.
1979-01-01
Topics covered include: (1) initial Cartesian coordinates for rapid precision orbit prediction; (2) accelerating convergence in optimization methods using search routines by applying curvilinear projection ideas; (3) perturbation-magnitude control for difference-quotient estimation of derivatives; and (4) determining the accelerometer bias for in-orbit shuttle trajectories.
2016-09-01
US (Siegel et al., 2014). The introduction of the prostate specific antigen ( PSA ) test has greatly aided to the early detection of PCa. Detectable...levels of PSA are the earliest sign of recurrent disease after radical prostatectomy (RP) (Pound et al., 1999). Besides its sensitiveness, it is...estimated that 23-44% of patients submitted to RP will progress with detectable PSA levels and will never present recurrence (Draisma et al., 2009). Thus
Li, Luyang; Liu, Yun-Hui; Jiang, Tianjiao; Wang, Kai; Fang, Mu
2018-02-01
Despite tremendous efforts made for years, trajectory tracking control (TC) of a nonholonomic mobile robot (NMR) without global positioning system remains an open problem. The major reason is the difficulty to localize the robot by using its onboard sensors only. In this paper, a newly designed adaptive trajectory TC method is proposed for the NMR without its position, orientation, and velocity measurements. The controller is designed on the basis of a novel algorithm to estimate position and velocity of the robot online from visual feedback of an omnidirectional camera. It is theoretically proved that the proposed algorithm yields the TC errors to asymptotically converge to zero. Real-world experiments are conducted on a wheeled NMR to validate the feasibility of the control system.
Tampubolon, Gindo
2015-07-01
In the public mind, later life is being transformed by the emerging possibility of a flourishing third age with sustained quality of life. We draw trajectories of life quality measured using CASP-19 over eight years. We refine these trajectories by jointly modelling attrition, since older people tend to leave longitudinal studies (attrite) not at random. Growth curve models are applied to the English Longitudinal Study of Ageing waves 1 to 5. Then joint model is estimated where attrition is considered. Extensive predictors are entered including demographic attributes, social and economic status, health conditions, and behaviours. Strong non-linear age trajectory of life quality is revealed by the growth curve models where the peak is achieved in the late 60s. Then the joint model uncovers the peak somewhat later in time, and also reveals secular improvement in life quality experienced by recent cohorts. Sharp estimates for many predictors of higher levels of life quality are also found. For the first time, the trajectories of life quality in the third age are drawn and improvement across cohorts is demonstrated. The contributions are estimated for predictors amenable to intervention such as social capital. This can help in policy discussion on improving the lives of older people in the third age.
NASA Technical Reports Server (NTRS)
Waters, Eric D.
2013-01-01
Recent high level interest in the capability of small launch vehicles has placed significant demand on determining the trade space these vehicles occupy. This has led to the development of a zero level analysis tool that can quickly determine the minimum expected vehicle gross liftoff weight (GLOW) in terms of vehicle stage specific impulse (Isp) and propellant mass fraction (pmf) for any given payload value. Utilizing an extensive background in Earth to orbit trajectory experience a total necessary delta v the vehicle must achieve can be estimated including relevant loss terms. This foresight into expected losses allows for more specific assumptions relating to the initial estimates of thrust to weight values for each stage. This tool was further validated against a trajectory model, in this case the Program to Optimize Simulated Trajectories (POST), to determine if the initial sizing delta v was adequate to meet payload expectations. Presented here is a description of how the tool is setup and the approach the analyst must take when using the tool. Also, expected outputs which are dependent on the type of small launch vehicle being sized will be displayed. The method of validation will be discussed as well as where the sizing tool fits into the vehicle design process.
Bullet trajectory reconstruction - Methods, accuracy and precision.
Mattijssen, Erwin J A T; Kerkhoff, Wim
2016-05-01
Based on the spatial relation between a primary and secondary bullet defect or on the shape and dimensions of the primary bullet defect, a bullet's trajectory prior to impact can be estimated for a shooting scene reconstruction. The accuracy and precision of the estimated trajectories will vary depending on variables such as, the applied method of reconstruction, the (true) angle of incidence, the properties of the target material and the properties of the bullet upon impact. This study focused on the accuracy and precision of estimated bullet trajectories when different variants of the probing method, ellipse method, and lead-in method are applied on bullet defects resulting from shots at various angles of incidence on drywall, MDF and sheet metal. The results show that in most situations the best performance (accuracy and precision) is seen when the probing method is applied. Only for the lowest angles of incidence the performance was better when either the ellipse or lead-in method was applied. The data provided in this paper can be used to select the appropriate method(s) for reconstruction and to correct for systematic errors (accuracy) and to provide a value of the precision, by means of a confidence interval of the specific measurement. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Visual Persons Behavior Diary Generation Model based on Trajectories and Pose Estimation
NASA Astrophysics Data System (ADS)
Gang, Chen; Bin, Chen; Yuming, Liu; Hui, Li
2018-03-01
The behavior pattern of persons was the important output of the surveillance analysis. This paper focus on the generation model of visual person behavior diary. The pipeline includes the person detection, tracking, and the person behavior classify. This paper adopts the deep convolutional neural model YOLO (You Only Look Once)V2 for person detection module. Multi person tracking was based on the detection framework. The Hungarian assignment algorithm was used to the matching. The person appearance model was integrated by HSV color model and Hash code model. The person object motion was estimated by the Kalman Filter. The multi objects were matching with exist tracklets through the appearance and motion location distance by the Hungarian assignment method. A long continuous trajectory for one person was get by the spatial-temporal continual linking algorithm. And the face recognition information was used to identify the trajectory. The trajectories with identification information can be used to generate the visual diary of person behavior based on the scene context information and person action estimation. The relevant modules are tested in public data sets and our own capture video sets. The test results show that the method can be used to generate the visual person behavior pattern diary with certain accuracy.
Estimates of cancer burden in Lazio.
Rashid, Ivan; Pannozzo, Fabio; Rossi, Silvia; Foschi, Roberto
2013-01-01
Since 1983 a population-based cancer registry has been operating in Lazio which provides incidence and survival data and covers the entire Latina province, amounting to 10% of the regional population. The aim of this paper is to provide estimates of the incidence, mortality and prevalence for seven major cancers in the Lazio region for the period 1970-2015. The estimates were obtained by applying the MIAMOD method, a statistical back-calculation approach to derive incidence and prevalence figures starting from mortality and relative survival data. Survival was modeled on the basis of published data from the Italian cancer registries. In 2012 the most frequent cancer sites were breast, colon-rectum and prostate with 5,529, 5,315 and 4,759 new diagnosed cases, respectively. The cancers with increasing incidence trends were breast cancer, lung cancer and skin melanoma in women, and prostate cancer, colorectal cancer and melanoma in men. The incidence rates of uterine cervix and stomach cancer decreased. The male lung cancer rates increased, reaching a peak in the late 1980s, and then decreased. Prevalence increased for all the considered cancers except cervix cancer. In 2012 breast, colorectal and prostate cancer had the highest prevalence, with 68,239, 36,617 and 33,934 prevalent cases, respectively. In the final period of the study the mortality declined for all cancers except female lung cancer. In 2012, the highest mortality rates were estimated for lung cancer in both men and women, with 89 and 40 deaths per 100,000, respectively. These estimates give a useful description of the present and future cancer patterns in the Lazio region. Incidence, mortality and prevalence projections provide new information for health resource planning. Furthermore, they point to the need to reinforce the organized screening programs, especially for breast and colorectal cancer.
Robot acting on moving bodies (RAMBO): Preliminary results
NASA Technical Reports Server (NTRS)
Davis, Larry S.; Dementhon, Daniel; Bestul, Thor; Ziavras, Sotirios; Srinivasan, H. V.; Siddalingaiah, Madju; Harwood, David
1989-01-01
A robot system called RAMBO is being developed. It is equipped with a camera, which, given a sequence of simple tasks, can perform these tasks on a moving object. RAMBO is given a complete geometric model of the object. A low level vision module extracts and groups characteristic features in images of the object. The positions of the object are determined in a sequence of images, and a motion estimate of the object is obtained. This motion estimate is used to plan trajectories of the robot tool to relative locations nearby the object sufficient for achieving the tasks. More specifically, low level vision uses parallel algorithms for image enchancement by symmetric nearest neighbor filtering, edge detection by local gradient operators, and corner extraction by sector filtering. The object pose estimation is a Hough transform method accumulating position hypotheses obtained by matching triples of image features (corners) to triples of model features. To maximize computing speed, the estimate of the position in space of a triple of features is obtained by decomposing its perspective view into a product of rotations and a scaled orthographic projection. This allows the use of 2-D lookup tables at each stage of the decomposition. The position hypotheses for each possible match of model feature triples and image feature triples are calculated in parallel. Trajectory planning combines heuristic and dynamic programming techniques. Then trajectories are created using parametric cubic splines between initial and goal trajectories. All the parallel algorithms run on a Connection Machine CM-2 with 16K processors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chung, Hyekyun
Purpose: Cone-beam CT (CBCT) is a widely used imaging modality for image-guided radiotherapy. Most vendors provide CBCT systems that are mounted on a linac gantry. Thus, CBCT can be used to estimate the actual 3-dimensional (3D) position of moving respiratory targets in the thoracic/abdominal region using 2D projection images. The authors have developed a method for estimating the 3D trajectory of respiratory-induced target motion from CBCT projection images using interdimensional correlation modeling. Methods: Because the superior–inferior (SI) motion of a target can be easily analyzed on projection images of a gantry-mounted CBCT system, the authors investigated the interdimensional correlation ofmore » the SI motion with left–right and anterior–posterior (AP) movements while the gantry is rotating. A simple linear model and a state-augmented model were implemented and applied to the interdimensional correlation analysis, and their performance was compared. The parameters of the interdimensional correlation models were determined by least-square estimation of the 2D error between the actual and estimated projected target position. The method was validated using 160 3D tumor trajectories from 46 thoracic/abdominal cancer patients obtained during CyberKnife treatment. The authors’ simulations assumed two application scenarios: (1) retrospective estimation for the purpose of moving tumor setup used just after volumetric matching with CBCT; and (2) on-the-fly estimation for the purpose of real-time target position estimation during gating or tracking delivery, either for full-rotation volumetric-modulated arc therapy (VMAT) in 60 s or a stationary six-field intensity-modulated radiation therapy (IMRT) with a beam delivery time of 20 s. Results: For the retrospective CBCT simulations, the mean 3D root-mean-square error (RMSE) for all 4893 trajectory segments was 0.41 mm (simple linear model) and 0.35 mm (state-augmented model). In the on-the-fly simulations, prior projections over more than 60° appear to be necessary for reliable estimations. The mean 3D RMSE during beam delivery after the simple linear model had established with a prior 90° projection data was 0.42 mm for VMAT and 0.45 mm for IMRT. Conclusions: The proposed method does not require any internal/external correlation or statistical modeling to estimate the target trajectory and can be used for both retrospective image-guided radiotherapy with CBCT projection images and real-time target position monitoring for respiratory gating or tracking.« less
Measuring Systematic Long-Term Trajectories of School Effectiveness Improvement
ERIC Educational Resources Information Center
Valenzuela, Juan Pablo; Bellei, Cristián; Allende, Claudio
2016-01-01
The objective of this study was to identify trajectories of school improvement experienced by Chilean elementary schools over the last decade. Using econometric analysis and controlling for potential confounding factors, we created an index of school performance combining outcome indicators focused on different school dimensions, and estimated the…
NASA Astrophysics Data System (ADS)
Swartling, Johannes; Höglund, Odd V.; Hansson, Kerstin; Södersten, Fredrik; Axelsson, Johan; Lagerstedt, Anne-Sofie
2016-02-01
Online light dosimetry with real-time feedback was applied for temoporfin-mediated interstitial photodynamic therapy (PDT) of dog prostate. The aim was to investigate the performance of online dosimetry by studying the correlation between light dose plans and the tissue response, i.e., extent of induced tissue necrosis and damage to surrounding organs at risk. Light-dose planning software provided dose plans, including light source positions and light doses, based on ultrasound images. A laser instrument provided therapeutic light and dosimetric measurements. The procedure was designed to closely emulate the procedure for whole-prostate PDT in humans with prostate cancer. Nine healthy dogs were subjected to the procedure according to a light-dose escalation plan. About 0.15 mg/kg temoporfin was administered 72 h before the procedure. The results of the procedure were assessed by magnetic resonance imaging, and gross pathology and histopathology of excised tissue. Light dose planning and online dosimetry clearly resulted in more focused effect and less damage to surrounding tissue than interstitial PDT without dosimetry. A light energy dose-response relationship was established where the threshold dose to induce prostate gland necrosis was estimated from 20 to 30 J/cm2.
Tanaka, Shiro; Matsuyama, Yutaka; Ohashi, Yasuo
2017-08-30
Increasing attention has been focused on the use and validation of surrogate endpoints in cancer clinical trials. Previous literature on validation of surrogate endpoints are classified into four approaches: the proportion explained approach; the indirect effects approach; the meta-analytic approach; and the principal stratification approach. The mainstream in cancer research has seen the application of a meta-analytic approach. However, VanderWeele (2013) showed that all four of these approaches potentially suffer from the surrogate paradox. It was also shown that, if a principal surrogate satisfies additional criteria called one-sided average causal sufficiency, the surrogate cannot exhibit a surrogate paradox. Here, we propose a method for estimating principal effects under a monotonicity assumption. Specifically, we consider cancer clinical trials which compare a binary surrogate endpoint and a time-to-event clinical endpoint under two naturally ordered treatments (e.g. combined therapy vs. monotherapy). Estimation based on a mean score estimating equation will be implemented by the expectation-maximization algorithm. We will also apply the proposed method as well as other surrogacy criteria to evaluate the surrogacy of prostate-specific antigen using data from a phase III advanced prostate cancer trial, clarifying the complementary roles of both the principal stratification and meta-analytic approaches in the evaluation of surrogate endpoints in cancer. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Choo, Min Soo; Yoo, Changwon; Cho, Sung Yong; Jeong, Seong Jin; Jeong, Chang Wook; Ku, Ja Hyeon; Oh, Seung-June
2017-04-01
As the elderly population increases, a growing number of patients have lower urinary tract symptom (LUTS)/benign prostatic hyperplasia (BPH). The aim of this study was to develop decision support formulas and nomograms for the prediction of bladder outlet obstruction (BOO) and for BOO-related surgical decision-making, and to validate them in patients with LUTS/BPH. Patient with LUTS/BPH between October 2004 and May 2014 were enrolled as a development cohort. The available variables included age, International Prostate Symptom Score, free uroflowmetry, postvoid residual volume, total prostate volume, and the results of a pressure-flow study. A causal Bayesian network analysis was used to identify relevant parameters. Using multivariate logistic regression analysis, formulas were developed to calculate the probabilities of having BOO and requiring prostatic surgery. Patients between June 2014 and December 2015 were prospectively enrolled for internal validation. Receiver operating characteristic curve analysis, calibration plots, and decision curve analysis were performed. A total of 1,179 male patients with LUTS/BPH, with a mean age of 66.1 years, were included as a development cohort. Another 253 patients were enrolled as an internal validation cohort. Using multivariate logistic regression analysis, 2 and 4 formulas were established to estimate the probabilities of having BOO and requiring prostatic surgery, respectively. Our analysis of the predictive accuracy of the model revealed area under the curve values of 0.82 for BOO and 0.87 for prostatic surgery. The sensitivity and specificity were 53.6% and 87.0% for BOO, and 91.6% and 50.0% for prostatic surgery, respectively. The calibration plot indicated that these prediction models showed a good correspondence. In addition, the decision curve analysis showed a high net benefit across the entire spectrum of probability thresholds. We established nomograms for the prediction of BOO and BOO-related prostatic surgery in patients with LUTS/BPH. Internal validation of the nomograms demonstrated that they predicted both having BOO and requiring prostatic surgery very well.
Heaphy, Christopher M.; Gaonkar, Gaurav; Peskoe, Sarah B.; Joshu, Corinne E.; De Marzo, Angelo M.; Lucia, M. Scott; Goodman, Phyllis J.; Lippman, Scott M.; Thompson, Ian M.; Platz, Elizabeth A.; Meeker, Alan K.
2015-01-01
Background Telomeres are repetitive nucleoproteins that help maintain chromosomal stability by inhibiting exonucleolytic degradation, prohibiting inappropriate homologous recombination, and preventing chromosomal fusions by suppressing double-strand break signals. We recently observed that men treated for clinically localized prostate cancer with shorter telomeres in their cancer-associated stromal cells, in combination with greater variation in cancer cell telomere lengths, were significantly more likely to progress to distant metastases and die from their disease. Here, we hypothesized that shorter stromal cell telomere length would be associated with prostate cancer risk at time of biopsy. Methods Telomere-specific fluorescence in situ hybridization (FISH) analysis was performed in normal-appearing stromal, basal epithelial, and luminal epithelial cells in biopsies from men randomized to the placebo arm of the Prostate Cancer Prevention Trial. Prostate cancer cases (N=32) were either detected on a biopsy performed for cause or at the end of the study per trial protocol, and controls (N=50), defined as negative for cancer on an end-of-study biopsy performed per trial protocol (e.g. irrespective of indication), were sampled. Logistic regression was used to estimate the association between mean telomere length of the particular cell populations, cell-to-cell telomere length variability, and risk of prostate cancer. Results Men with short stromal cell telomere lengths (below median) had 2.66 (95% CI 1.04-3.06; p=0.04) times the odds of prostate cancer compared with men who had longer lengths (at or above median). Conversely, we did not observe statistically significant associations for short telomere lengths in normal-appearing basal (OR=2.15, 95% CI 0.86-5.39; p=0.10) or luminal (OR=1.15, 95% CI 0.47-2.80; p=0.77) cells. Conclusions These findings suggest that telomere shortening in normal stromal cells is associated with prostate cancer risk. It is essential to extend and validate these findings, while also identifying the cellular milieu that comprises the subset of cells with short telomeres within the prostate tumor microenvironment. PMID:25893825
Heaphy, Christopher M; Gaonkar, Gaurav; Peskoe, Sarah B; Joshu, Corinne E; De Marzo, Angelo M; Lucia, M Scott; Goodman, Phyllis J; Lippman, Scott M; Thompson, Ian M; Platz, Elizabeth A; Meeker, Alan K
2015-08-01
Telomeres are repetitive nucleoproteins that help maintain chromosomal stability by inhibiting exonucleolytic degradation, prohibiting inappropriate homologous recombination, and preventing chromosomal fusions by suppressing double-strand break signals. We recently observed that men treated for clinically localized prostate cancer with shorter telomeres in their cancer-associated stromal cells, in combination with greater variation in cancer cell telomere lengths, were significantly more likely to progress to distant metastases, and die from their disease. Here, we hypothesized that shorter stromal cell telomere length would be associated with prostate cancer risk at time of biopsy. Telomere-specific fluorescence in situ hybridization (FISH) analysis was performed in normal-appearing stromal, basal epithelial, and luminal epithelial cells in biopsies from men randomized to the placebo arm of the Prostate Cancer Prevention Trial. Prostate cancer cases (N = 32) were either detected on a biopsy performed for cause or at the end of the study per trial protocol, and controls (N = 50), defined as negative for cancer on an end-of-study biopsy performed per trial protocol (e.g., irrespective of indication), were sampled. Logistic regression was used to estimate the association between mean telomere length of the particular cell populations, cell-to-cell telomere length variability, and risk of prostate cancer. Men with short stromal cell telomere lengths (below median) had 2.66 (95% CI 1.04-3.06; P = 0.04) times the odds of prostate cancer compared with men who had longer lengths (at or above median). Conversely, we did not observe statistically significant associations for short telomere lengths in normal-appearing basal (OR = 2.15, 95% CI 0.86-5.39; P= 0 .10) or luminal (OR = 1.15, 95% CI 0.47-2.80; P = 0.77) cells. These findings suggest that telomere shortening in normal stromal cells is associated with prostate cancer risk. It is essential to extend and validate these findings, while also identifying the cellular milieu that comprises the subset of cells with short telomeres within the prostate tumor microenvironment. © 2015 Wiley Periodicals, Inc.
Guidance, steering, load relief and control of an asymmetric launch vehicle. M.S. Thesis - MIT
NASA Technical Reports Server (NTRS)
Boelitz, Frederick W.
1989-01-01
A new guidance, steering, and control concept is described and evaluated for the Third Phase of an asymmetrical configuration of the Advanced Launch System (ALS). The study also includes the consideration of trajectory shaping issues and trajectory design as well as the development of angular rate, angular acceleration, angle of attack, and dynamic pressure estimators. The Third Phase guidance, steering and control system is based on controlling the acceleration-direction of the vehicle after an initial launch maneuver. Unlike traditional concepts, the alignment of the estimated and commanded acceleration-directions is unimpaired by an add-on load relief. Instead, the acceleration-direction steering-control system features a control override that limits the product of estimated dynamic pressure and estimated angle of attack. When this product is not being limited, control is based exclusively on the commanded acceleration-direction without load relief. During limiting, control is based on nulling the error between the limited angle of attack and the estimated angle of attack. This limiting feature provides full freedom to the acceleration-direction steering and control to shape the trajectory within the limit, and also gives full priority to the limiting of angle of attack when necessary. The flight software concepts were analyzed on the basis of their effects on pitch plane motion.
NASA Astrophysics Data System (ADS)
Galanti, Eli; Durante, Daniele; Finocchiaro, Stefano; Iess, Luciano; Kaspi, Yohai
2017-07-01
The upcoming Juno spacecraft measurements have the potential of improving our knowledge of Jupiter’s gravity field. The analysis of the Juno Doppler data will provide a very accurate reconstruction of spatial gravity variations, but these measurements will be very accurate only over a limited latitudinal range. In order to deduce the full gravity field of Jupiter, additional information needs to be incorporated into the analysis, especially regarding the Jovian flow structure and its depth, which can influence the measured gravity field. In this study we propose a new iterative method for the estimation of the Jupiter gravity field, using a simulated Juno trajectory, a trajectory estimation model, and an adjoint-based inverse model for the flow dynamics. We test this method both for zonal harmonics only and with a full gravity field including tesseral harmonics. The results show that this method can fit some of the gravitational harmonics better to the “measured” harmonics, mainly because of the added information from the dynamical model, which includes the flow structure. Thus, it is suggested that the method presented here has the potential of improving the accuracy of the expected gravity harmonics estimated from the Juno and Cassini radio science experiments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Galanti, Eli; Kaspi, Yohai; Durante, Daniele
The upcoming Juno spacecraft measurements have the potential of improving our knowledge of Jupiter’s gravity field. The analysis of the Juno Doppler data will provide a very accurate reconstruction of spatial gravity variations, but these measurements will be very accurate only over a limited latitudinal range. In order to deduce the full gravity field of Jupiter, additional information needs to be incorporated into the analysis, especially regarding the Jovian flow structure and its depth, which can influence the measured gravity field. In this study we propose a new iterative method for the estimation of the Jupiter gravity field, using a simulatedmore » Juno trajectory, a trajectory estimation model, and an adjoint-based inverse model for the flow dynamics. We test this method both for zonal harmonics only and with a full gravity field including tesseral harmonics. The results show that this method can fit some of the gravitational harmonics better to the “measured” harmonics, mainly because of the added information from the dynamical model, which includes the flow structure. Thus, it is suggested that the method presented here has the potential of improving the accuracy of the expected gravity harmonics estimated from the Juno and Cassini radio science experiments.« less
Calcium-Sensing Receptor Tumor Expression and Lethal Prostate Cancer Progression.
Ahearn, Thomas U; Tchrakian, Nairi; Wilson, Kathryn M; Lis, Rosina; Nuttall, Elizabeth; Sesso, Howard D; Loda, Massimo; Giovannucci, Edward; Mucci, Lorelei A; Finn, Stephen; Shui, Irene M
2016-06-01
Prostate cancer metastases preferentially target bone, and the calcium-sensing receptor (CaSR) may play a role in promoting this metastatic progression. We evaluated the association of prostate tumor CaSR expression with lethal prostate cancer. A validated CaSR immunohistochemistry assay was performed on tumor tissue microarrays. Vitamin D receptor (VDR) expression and phosphatase and tensin homolog tumor status were previously assessed in a subset of cases by immunohistochemistry. Cox proportional hazards models adjusting for age and body mass index at diagnosis, Gleason grade, and pathological tumor node metastasis stage were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of CaSR expression with lethal prostate cancer. The investigation was conducted in the Health Professionals Follow-up Study and Physicians' Health Study. We studied 1241 incident prostate cancer cases diagnosed between 1983 and 2009. Participants were followed up or cancer-specific mortality or development of metastatic disease. On average, men were followed up 13.6 years, during which there were 83 lethal events. High CaSR expression was associated with lethal prostate cancer independent of clinical and pathological variables (HR 2.0; 95% CI 1.2-3.3). Additionally, there was evidence of effect modification by VDR expression; CaSR was associated with lethal progression among men with low tumor VDR expression (HR 3.2; 95% CI 1.4-7.3) but not in cases with high tumor VDR expression (HR 0.8; 95% CI 0.2-3.0). Tumor CaSR expression is associated with an increased risk of lethal prostate cancer, particularly in tumors with low VDR expression. These results support further investigating the mechanism linking CaSR with metastases.
Travis, Ruth C.; Appleby, Paul N.; Martin, Richard M.; Holly, Jeff M.P.; Albanes, Demetrius; Black, Amanda; Bueno-de-Mesquita, H.B(as).; Chan, June M.; Chen, Chu; Chirlaque, Maria-Dolores; Cook, Michael B.; Deschasaux, Mélanie; Donovan, Jenny L.; Ferrucci, Luigi; Galan, Pilar; Giles, Graham G.; Giovannucci, Edward L.; Gunter, Marc J.; Habel, Laurel A.; Hamdy, Freddie C.; Helzlsouer, Kathy J.; Hercberg, Serge; Hoover, Robert N.; Janssen, Joseph A.M.J.L.; Kaaks, Rudolf; Kubo, Tatsuhiko; Le Marchand, Loic; Metter, E. Jeffrey; Mikami, Kazuya; Morris, Joan K.; Neal, David E.; Neuhouser, Marian L.; Ozasa, Kotaro; Palli, Domenico; Platz, Elizabeth A.; Pollak, Michael; Price, Alison J.; Roobol, Monique J.; Schaefer, Catherine; Schenk, Jeannette M.; Severi, Gianluca; Stampfer, Meir J.; Stattin, Pär; Tamakoshi, Akiko; Tangen, Catherine M.; Touvier, Mathilde; Wald, Nicholas J.; Weiss, Noel S.; Ziegler, Regina G.
2016-01-01
The role of insulin-like growth factors (IGFs) in prostate cancer development is not fully understood. To investigate the association between circulating concentrations of IGFs (IGF-I, IGF-II, IGFBP-1, IGFBP-2, IGFBP-3) and prostate cancer risk, we pooled individual participant data from 17 prospective and two cross-sectional studies, including up to 10,554 prostate cancer cases and 13,618 control participants. Conditional logistic regression was used to estimate the odds ratios (ORs) for prostate cancer based on the study-specific fifth of each analyte. Overall, IGF-I, IGF-II, IGFBP-2, and IGFBP-3 concentrations were positively associated with prostate cancer risk (Ptrend all ≤ 0.005), and IGFBP-1 was weakly inversely associated with risk (Ptrend = 0.05). However, heterogeneity between the prospective and cross-sectional studies was evident (Pheterogeneity = 0.03), unless the analyses were restricted to prospective studies (with the exception of IGF-II, Pheterogeneity = 0.02). For prospective studies, the OR for men in the highest versus the lowest fifth of each analyte was 1.29 (95% confidence interval=1.16-1.43) for IGF-I, 0.81 (0.68-0.96) for IGFBP-1, and 1.25 (1.12-1.40) for IGFBP-3. These associations did not differ significantly by time-to-diagnosis or tumor stage or grade. After mutual adjustment for each of the other analytes, only IGF-I remained associated with risk. Our collaborative study represents the largest pooled analysis of the relationship between prostate cancer risk and circulating concentrations of IGF-I, providing strong evidence that IGF-I is highly likely to be involved in prostate cancer development. PMID:26921328
Hutchinson, Ryan C; Costa, Daniel N; Lotan, Yair
2016-07-01
Prostate magnetic resonance imaging (MRI) is a maturing imaging modality that has been used to improve detection and staging of prostate cancer. The goal of this review is to evaluate the economic effect of the use of MRI and MRI fusion in the diagnosis of prostate cancer. A literature review was used to identify articles regarding efficacy and cost of MRI and MRI-guided biopsies. There are currently a limited number of studies evaluating cost of incorporating MRI into clinical practice. These studies are primarily models projecting cost estimates based on meta-analyses of the literature. There is considerable variance in the effectiveness of MRI-guided biopsies, both cognitive and fusion, based on user experience, type of MRI (3T vs. 1.5T), use of endorectal coil and type of scoring system for abnormalities such that there is still potential for improvement in accuracy. There is also variability in assumed costs of incorporating MRI into clinical practice. The addition of MRI to the diagnostic algorithm for prostate cancer has caused a shift in how we understand the disease and in what tumors are found on initial and repeat biopsies. Further risk stratification may allow more men to pursue noncurative therapy, which in and of itself is cost-effective in properly selected men. As prostate cancer care comes under increasing scrutiny on a national level, there is pressure on providers to be more accurate in their diagnoses. This in turn can lead to additional testing including Multiparametric MRI, which adds upfront cost. Whether the additional cost of prostate MRI is warranted in detection of prostate cancer is an area of intense research. Copyright © 2016 Elsevier Inc. All rights reserved.
Hoffmann, Richard; Logan, Callum; O'Callaghan, Michael; Gormly, Kirsten; Chan, Ken; Foreman, Darren
2018-01-01
Multiparametric MRI (mpMRI) is useful in detecting anterior prostate tumours. Due to the location of anterior tumours, they are often diagnosed with a large size and may be suspicious for extra-prostatic extension (EPE). We aim to evaluate whether PI-RADS v2 is more accurate in assessing anterior prostate lesions identified on mpMRI compared to PI-RADS v1. Patients with anterior prostate lesions diagnosed on mpMRI who proceeded to a cognitive fusion transperineal prostate biopsy were identified. Each mpMRI was blinded and read by two experienced prostate MRI radiologists and assigned a PI-RADS v1 and PI-RADS v2 score, and the presence of EPE was estimated. Correlation was made with transperineal histopathology and, where relevant, radical prostatectomy histopathology. Concordance measures between PI-RADS v1 and PI-RADS v2, and between examiners of the same PI-RADS score were calculated using a weighted kappa. Fifty-eight consecutive men were identified. Concordance between the examiners for PI-RADS v1 and for v2 showed substantial agreement (version 1: weighted kappa 0.71; version 2: weighted kappa 0.69). There was no difference in accuracy when using PI-RADS v1 or PI-RADS v2 to predict clinically significant cancer. There was poor correlation between EPE measured on mpMRI compared with EPE in radical prostatectomy histopathology. PI-RADS v2 is reproducible between radiologists but does not have improved accuracy for diagnosing anterior tumours of the prostate when compared to PI-RADS v1. Multiparametric MRI is accurate at detecting anterior tumours with a sensitivity of 86-88%.
MAGI2 is an independent predictor of biochemical recurrence in prostate cancer.
David, Stephanie N; Arnold Egloff, Shanna A; Goyal, Rajen; Clark, Peter E; Phillips, Sharon; Gellert, Lan L; Hameed, Omar; Giannico, Giovanna A
2018-06-01
Membrane-associated guanylate kinase, WW and PDZ domain-containing protein 2 (MAGI2) promotes the activity of phosphatase and tensin homolog (PTEN). Recent studies suggest that dysregulation of this signaling pathway has a role in prostate carcinogenesis. Our study aims to determine the prognostic significance of MAGI2 expression in prostate cancer. Tissue microarrays from 51 radical prostatectomy cases including benign prostatic tissue, high grade prostatic intraepithelial neoplasia (HGPIN), and adenocarcinoma were constructed. Immunohistochemistry with double staining for MAGI2 and p63 was performed and analyzed by image analysis as percent of analyzed area (%AREA). Multivariable logistic regression was used to correlate MAGI2 expression with clinical outcomes. Generalized Estimating Equations (GEE) with linear and logistic regression was used to correlate MAGI2 with intrapatient histology. MAGI2 %AREA was inversely associated with progression from HGPIN to adenocarcinoma of low to high Gleason score (OR, 0.980; slope, -0.02; P = 0.005) and HGPIN to cancer of any Gleason score (OR, 0.969; P = 0.007). After adjusting for grade, stage, and margin status, MAGI2 %AREA was a significant independent predictor of biochemical recurrence (BCR) (OR, 0.936; 95%CI, 0.880-0.996; P = 0.037; bootstrap P = 0.017). The addition of MAGI2 %AREA to these standard clinical parameters improved accuracy of predicting BCR by 2.9% (91.0% vs 88.1%). These results reveal that MAGI2 expression is reduced during prostate cancer progression and that retention of MAGI2 signal reduces odds of BCR. The study results further suggest a possible role of MAGI2 in prostate neoplasia. Decreased MAGI2 expression may help predict prostate cancer aggressiveness and provide new insight for treatment decisions and post-operative surveillance intervals. © 2018 Wiley Periodicals, Inc.
Zöller, Bengt; Li, Xinjun; Sundquist, Jan; Sundquist, Kristina
2014-09-01
Familial clustering of prostate, breast and colorectal cancer is well established, but the familial risk of these cancers has not been determined among adoptees. The aim was to disentangle the contributions of genetic and environmental factors to the familial transmission of prostate, breast and colorectal cancer. The Swedish Multi-Generation Register was used to follow all adoptees born between 1932 and 1969 (n=70,965) for prostate, breast and colorectal cancer from January 1958 up to December 2010. The risk of prostate, breast and colorectal cancer was estimated in adoptees with at least one biological parent with the same cancer type compared with adoptees without a biological parent with the same cancer type. The risk of cancer was also determined in adoptees with at least one adoptive parent with cancer compared with adoptees with an adoptive parent without cancer. Adoptees with at least one biological parent with prostate, breast or colorectal cancer were more likely to have cancer of the same type than adoptees with biological parents not affected by these respective cancer types (standardised incidence ratio=SIR: 1.8 [95% confidence interval 1.2-2.7], 2.0 [1.6-2.5] and 1.9 [1.2-2.9], respectively). In contrast, adoptees with at least one adoptive parent with prostate, breast or colorectal cancer were not at an increased risk of these respective cancer types (SIR=1.2 [0.94-1.6], 0.97 [0.71-1.3], and 1.1 [0.71-1.5], respectively). The findings of the study support the importance of genetic/biological factors in the familial transmission of prostate, breast and colorectal cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.
Asthma and risk of lethal prostate cancer in the Health Professionals Follow-Up Study.
Platz, Elizabeth A; Drake, Charles G; Wilson, Kathryn M; Sutcliffe, Siobhan; Kenfield, Stacey A; Mucci, Lorelei A; Stampfer, Meir J; Willett, Walter C; Camargo, Carlos A; Giovannucci, Edward
2015-08-15
Inflammation, and more generally, the immune response are thought to influence the development of prostate cancer. To determine the components of the immune response that are potentially contributory, we prospectively evaluated the association of immune-mediated conditions, asthma and hayfever, with lethal prostate cancer risk in the Health Professionals Follow-up Study. We included 47,880 men aged 40-75 years with no prior cancer diagnosis. On the baseline questionnaire in 1986, the men reported diagnoses of asthma and hayfever and year of onset. On the follow-up questionnaires, they reported new asthma and prostate cancer diagnoses. We used Cox proportional hazards regression to estimate relative risks (RRs). In total, 9.2% reported ever having been diagnosed with asthma. In all, 25.3% reported a hayfever diagnosis at baseline. During 995,176 person-years of follow-up by 2012, we confirmed 798 lethal prostate cancer cases (diagnosed with distant metastases, progressed to distant metastasis or died of prostate cancer [N = 625]). Ever having a diagnosis of asthma was inversely associated with risk of lethal (RR = 0.71, 95% confidence interval [CI] = 0.51-1.00) and fatal (RR = 0.64, 95% CI = 0.42-0.96) disease. Hayfever with onset in the distant past was possibly weakly positively associated with risk of lethal (RR = 1.10, 95% CI = 0.92-1.33) and fatal (RR = 1.12, 95% CI = 0.91-1.37) disease. Men who were ever diagnosed with asthma were less likely to develop lethal and fatal prostate cancer. Our findings may lead to testable hypotheses about specific immune profiles in the etiology of lethal prostate cancer. © 2015 UICC.
Alignment of cryo-EM movies of individual particles by optimization of image translations.
Rubinstein, John L; Brubaker, Marcus A
2015-11-01
Direct detector device (DDD) cameras have revolutionized single particle electron cryomicroscopy (cryo-EM). In addition to an improved camera detective quantum efficiency, acquisition of DDD movies allows for correction of movement of the specimen, due to both instabilities in the microscope specimen stage and electron beam-induced movement. Unlike specimen stage drift, beam-induced movement is not always homogeneous within an image. Local correlation in the trajectories of nearby particles suggests that beam-induced motion is due to deformation of the ice layer. Algorithms have already been described that can correct movement for large regions of frames and for >1 MDa protein particles. Another algorithm allows individual <1 MDa protein particle trajectories to be estimated, but requires rolling averages to be calculated from frames and fits linear trajectories for particles. Here we describe an algorithm that allows for individual <1 MDa particle images to be aligned without frame averaging or linear trajectories. The algorithm maximizes the overall correlation of the shifted frames with the sum of the shifted frames. The optimum in this single objective function is found efficiently by making use of analytically calculated derivatives of the function. To smooth estimates of particle trajectories, rapid changes in particle positions between frames are penalized in the objective function and weighted averaging of nearby trajectories ensures local correlation in trajectories. This individual particle motion correction, in combination with weighting of Fourier components to account for increasing radiation damage in later frames, can be used to improve 3-D maps from single particle cryo-EM. Copyright © 2015 Elsevier Inc. All rights reserved.
Results of the Magnetometer Navigation (MAGNAV)lnflight Experiment
NASA Technical Reports Server (NTRS)
Thienel, Julie K.; Harman, Richard R.; Bar-Itzhack, Itzhack Y.; Lambertson, Mike
2004-01-01
The Magnetometer Navigation (MAGNAV) algorithm is currently running as a flight experiment as part of the Wide Field Infrared Explorer (WIRE) Post-Science Engineering Testbed. Initialization of MAGNAV occurred on September 4, 2003. MAGNAV is designed to autonomously estimate the spacecraft orbit, attitude, and rate using magnetometer and sun sensor data. Since the Earth's magnetic field is a function of time and position, and since time is known quite precisely, the differences between the computed magnetic field and measured magnetic field components, as measured by the magnetometer throughout the entire spacecraft orbit, are a function of the spacecraft trajectory and attitude errors. Therefore, these errors are used to estimate both trajectory and attitude. In addition, the time rate of change of the magnetic field vector is used to estimate the spacecraft rotation rate. The estimation of the attitude and trajectory is augmented with the rate estimation into an Extended Kalman filter blended with a pseudo-linear Kalman filter. Sun sensor data is also used to improve the accuracy and observability of the attitude and rate estimates. This test serves to validate MAGNAV as a single low cost navigation system which utilizes reliable, flight qualified sensors. MAGNAV is intended as a backup algorithm, an initialization algorithm, or possibly a prime navigation algorithm for a mission with coarse requirements. Results from the first six months of operation are presented.
The Effects of Partnered Exercise on Physical Intimacy in Couples Coping with Prostate Cancer
Lyons, Karen S.; Winters-Stone, Kerri M.; Bennett, Jill A.; Beer, Tomasz M.
2015-01-01
Objective The study examined whether couples coping with prostate cancer participating in a partnered exercise program - Exercising Together (ET) - experienced higher levels of physical intimacy (i.e., affectionate & sexual behavior) than couples in a usual care (UC) control group. Method Men and their wives (n=64 couples) were randomly assigned to either the ET or UC group. Couples in the ET group engaged in partnered strength-training twice weekly for six months. Multilevel modeling was used to explore the effects of ET on husband and wife engagement in both affectionate and sexual behaviors over time. Results Controlling for relationship quality, wives in ET showed significant increases in engagement in affectionate behaviors compared to wives in UC. No intervention effects were found for husbands. Conclusion Couple-based approaches to physical intimacy, after a cancer diagnosis, that facilitate collaborative engagement in non-sexual physical activities for the couple have potential to be effective for wives. More research is needed in this area to determine couples most amenable to such exercise strategies, optimal timing in the cancer trajectory, and the benefits of combining partnered exercise with more traditional relationship-focused strategies. PMID:26462060
Short- and long-term use of medication for psychological distress after the diagnosis of cancer.
Wang, Cheng-Hsu; Huang, Lynn Chu; Yang, Chen-Chang; Chen, Chi-Liang; Chou, Yiing-Jenq; Chen, Yen-Yuan; Yang, Wei-Chih; Chen, Likwang
2017-03-01
This study investigated the short- and long-term use of medication for psychological distress after the diagnosis of cancer. Longitudinal data from the Taiwan National Health Insurance database were used to follow 35,137 cancer patients for 2.5 years after being diagnosed in 2006 and 2007. Among those patients who survived for at least 180 days, 20.9 % had used psychotropic medications; sedatives were the most frequently prescribed (14.3 %), followed by antidepressants (5.5 %), anxiolytics (3.6 %), and antipsychotics (2.7 %). Lung cancer, prostate cancer, and oral cancer showed a significant association with the regular use of medication in the first 180 days. Among patients who survived for at least 2.5 years, 4.8 % still used psychotropic medication on a regular basis. Lung cancer and prostate cancer were associated with such prolonged use. This longitudinal study found that the type of cancer was significantly associated with the use of psychotropic drugs after the diagnosis was made. It provided information about the trajectory of that use and found that a small number of patients were still using those medications after 2.5 years.
Folio, Les R; Fischer, Tatjana; Shogan, Paul; Frew, Michael; Dwyer, Andrew; Provenzale, James M
2011-08-01
The purpose of this study is to determine the agreement with which radiologists identify wound paths in vivo on MDCT and calculate missile trajectories on the basis of Cartesian coordinates using a Cartesian positioning system (CPS). Three radiologists retrospectively identified 25 trajectories on MDCT in 19 casualties who sustained penetrating trauma in Iraq. Trajectories were described qualitatively in terms of directional path descriptors and quantitatively as trajectory vectors. Directional descriptors, trajectory angles, and angles between trajectories were calculated based on Cartesian coordinates of entrance and terminus or exit recorded in x, y image and table space (z) using a Trajectory Calculator created using spreadsheet software. The consistency of qualitative descriptor determinations was assessed in terms of frequency of observer agreement and multirater kappa statistics. Consistency of trajectory vectors was evaluated in terms of distribution of magnitude of the angles between vectors and the differences between their paraaxial and parasagittal angles. In 68% of trajectories, the observers' visual assessment of qualitative descriptors was congruent. Calculated descriptors agreed across observers in 60% of the trajectories. Estimated kappa also showed good agreement (0.65-0.79, p < 0.001); 70% of calculated paraaxial and parasagittal angles were within 20° across observers, and 61.3% of angles between trajectory vectors were within 20° across observers. Results show agreement of visually assessed and calculated qualitative descriptors and trajectory angles among observers. The Trajectory Calculator describes trajectories qualitatively similar to radiologists' visual assessment, showing the potential feasibility of automated trajectory analysis.
Modern Methods for Modeling Change in Obesity Research in Nursing.
Sereika, Susan M; Zheng, Yaguang; Hu, Lu; Burke, Lora E
2017-08-01
Persons receiving treatment for weight loss often demonstrate heterogeneity in lifestyle behaviors and health outcomes over time. Traditional repeated measures approaches focus on the estimation and testing of an average temporal pattern, ignoring the interindividual variability about the trajectory. An alternate person-centered approach, group-based trajectory modeling, can be used to identify distinct latent classes of individuals following similar trajectories of behavior or outcome change as a function of age or time and can be expanded to include time-invariant and time-dependent covariates and outcomes. Another latent class method, growth mixture modeling, builds on group-based trajectory modeling to investigate heterogeneity within the distinct trajectory classes. In this applied methodologic study, group-based trajectory modeling for analyzing changes in behaviors or outcomes is described and contrasted with growth mixture modeling. An illustration of group-based trajectory modeling is provided using calorie intake data from a single-group, single-center prospective study for weight loss in adults who are either overweight or obese.
NASA Astrophysics Data System (ADS)
Saroglou, Charalampos; Asteriou, Pavlos; Zekkos, Dimitrios; Tsiambaos, George; Clark, Marin; Manousakis, John
2018-01-01
We present field evidence and a kinematic study of a rock block mobilized in the Ponti area by a Mw = 6.5 earthquake near the island of Lefkada on 17 November 2015. A detailed survey was conducted using an unmanned aerial vehicle (UAV) with an ultrahigh definition (UHD) camera, which produced a high-resolution orthophoto and a digital terrain model (DTM). The sequence of impact marks from the rock trajectory on the ground surface was identified from the orthophoto and field verified. Earthquake characteristics were used to estimate the acceleration of the rock slope and the initial condition of the detached block. Using the impact points from the measured rockfall trajectory, an analytical reconstruction of the trajectory was undertaken, which led to insights on the coefficients of restitution (CORs). The measured trajectory was compared with modeled rockfall trajectories using recommended parameters. However, the actual trajectory could not be accurately predicted, revealing limitations of existing rockfall analysis software used in engineering practice.
Potential sources of precipitation in Lake Baikal basin
NASA Astrophysics Data System (ADS)
Shukurov, K. A.; Mokhov, I. I.
2017-11-01
Based on the data of long-term measurements at 23 meteorological stations in the Russian part of the Lake Baikal basin the probabilities of daily precipitation with different intensity and their contribution to the total precipitation are estimated. Using the trajectory model HYSPLIT_4 for each meteorological station for the period 1948-2016 the 10-day backward trajectories of air parcels, the height of these trajectories and distribution of specific humidity along the trajectories are calculated. The average field of power of potential sources of daily precipitation (less than 10 mm) for all meteorological stations in the Russian part of the Lake Baikal basin was obtained using the CWT (concentration weighted trajectory) method. The areas have been identified from which within 10 days water vapor can be transported to the Lake Baikal basin, as well as regions of the most and least powerful potential sources. The fields of the mean height of air parcels trajectories and the mean specific humidity along the trajectories are compared with the field of mean power of potential sources.
Prostate Cancer and Ambient Pesticide Exposure in Agriculturally Intensive Areas in California
Cockburn, Myles; Mills, Paul; Zhang, Xinbo; Zadnick, John; Goldberg, Dan; Ritz, Beate
2011-01-01
In a population-based case-control study in California's intensely agricultural Central Valley (2005–2006), the authors investigated relations between environmental pesticide/fungicide exposure and prostate cancer. Cases (n = 173) were obtained from a population-based cancer registry, and controls (n = 162) were obtained from Medicare listings and tax assessor mailings. Past ambient exposures to pesticides/fungicides were derived from residential history and independently recorded pesticide and land-use data, using a novel geographic information systems approach. In comparison with unexposed persons, increased risks of prostate cancer were observed among persons exposed to compounds which may have prostate-specific biologic effects (methyl bromide (odds ratio = 1.62, 95% confidence interval: 1.02, 2.59) and a group of organochlorines (odds ratio = 1.64, 95% confidence interval: 1.02, 2.63)) but not among those exposed to other compounds that were included as controls (simazine, maneb, and paraquat dichloride). The authors assessed the possibility of selection bias due to less-than-100% enrollment of eligible cases and controls (a critical methodological concern in studies of this kind) and determined that there was little evidence of bias affecting the estimated effect size. This study provides evidence of an association between prostate cancer and ambient pesticide exposures in and around homes in intensely agricultural areas. The associations appear specific to compounds with a plausible biologic role in prostate carcinogenesis. PMID:21447478
Major, Jacqueline M; Norman Oliver, M; Doubeni, Chyke A; Hollenbeck, Albert R; Graubard, Barry I; Sinha, Rashmi
2012-07-01
The purpose of this study was to separately examine the impact of neighborhood socioeconomic deprivation and availability of healthcare resources on prostate cancer risk among African American and Caucasian men. In the large, prospective NIH-AARP Diet and Health Study, we analyzed baseline (1995-1996) data from adult men, aged 50-71 years. Incident prostate cancer cases (n = 22,523; 1,089 among African Americans) were identified through December 2006. Lifestyle and health risk information was ascertained by questionnaires administered at baseline. Area-level socioeconomic indicators were ascertained by linkage to the US Census and the Area Resource File. Multilevel Cox models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs). A differential effect among African Americans and Caucasians was observed for neighborhood deprivation (p-interaction = 0.04), percent uninsured (p-interaction = 0.02), and urologist density (p-interaction = 0.01). Compared to men living in counties with the highest density of urologists, those with fewer had a substantially increased risk of developing advanced prostate cancer (HR = 2.68, 95 % CI = 1.31, 5.47) among African American. Certain socioeconomic indicators were associated with an increased risk of prostate cancer among African American men compared to Caucasians. Minimizing differences in healthcare availability may be a potentially important pathway to minimizing disparities in prostate cancer risk.
Robot Acting on Moving Bodies (RAMBO): Interaction with tumbling objects
NASA Technical Reports Server (NTRS)
Davis, Larry S.; Dementhon, Daniel; Bestul, Thor; Ziavras, Sotirios; Srinivasan, H. V.; Siddalingaiah, Madhu; Harwood, David
1989-01-01
Interaction with tumbling objects will become more common as human activities in space expand. Attempting to interact with a large complex object translating and rotating in space, a human operator using only his visual and mental capacities may not be able to estimate the object motion, plan actions or control those actions. A robot system (RAMBO) equipped with a camera, which, given a sequence of simple tasks, can perform these tasks on a tumbling object, is being developed. RAMBO is given a complete geometric model of the object. A low level vision module extracts and groups characteristic features in images of the object. The positions of the object are determined in a sequence of images, and a motion estimate of the object is obtained. This motion estimate is used to plan trajectories of the robot tool to relative locations rearby the object sufficient for achieving the tasks. More specifically, low level vision uses parallel algorithms for image enhancement by symmetric nearest neighbor filtering, edge detection by local gradient operators, and corner extraction by sector filtering. The object pose estimation is a Hough transform method accumulating position hypotheses obtained by matching triples of image features (corners) to triples of model features. To maximize computing speed, the estimate of the position in space of a triple of features is obtained by decomposing its perspective view into a product of rotations and a scaled orthographic projection. This allows use of 2-D lookup tables at each stage of the decomposition. The position hypotheses for each possible match of model feature triples and image feature triples are calculated in parallel. Trajectory planning combines heuristic and dynamic programming techniques. Then trajectories are created using dynamic interpolations between initial and goal trajectories. All the parallel algorithms run on a Connection Machine CM-2 with 16K processors.
Precomputing Process Noise Covariance for Onboard Sequential Filters
NASA Technical Reports Server (NTRS)
Olson, Corwin G.; Russell, Ryan P.; Carpenter, J. Russell
2017-01-01
Process noise is often used in estimation filters to account for unmodeled and mismodeled accelerations in the dynamics. The process noise covariance acts to inflate the state covariance over propagation intervals, increasing the uncertainty in the state. In scenarios where the acceleration errors change significantly over time, the standard process noise covariance approach can fail to provide effective representation of the state and its uncertainty. Consider covariance analysis techniques provide a method to precompute a process noise covariance profile along a reference trajectory using known model parameter uncertainties. The process noise covariance profile allows significantly improved state estimation and uncertainty representation over the traditional formulation. As a result, estimation performance on par with the consider filter is achieved for trajectories near the reference trajectory without the additional computational cost of the consider filter. The new formulation also has the potential to significantly reduce the trial-and-error tuning currently required of navigation analysts. A linear estimation problem as described in several previous consider covariance analysis studies is used to demonstrate the effectiveness of the precomputed process noise covariance, as well as a nonlinear descent scenario at the asteroid Bennu with optical navigation.
Precomputing Process Noise Covariance for Onboard Sequential Filters
NASA Technical Reports Server (NTRS)
Olson, Corwin G.; Russell, Ryan P.; Carpenter, J. Russell
2017-01-01
Process noise is often used in estimation filters to account for unmodeled and mismodeled accelerations in the dynamics. The process noise covariance acts to inflate the state covariance over propagation intervals, increasing the uncertainty in the state. In scenarios where the acceleration errors change significantly over time, the standard process noise covariance approach can fail to provide effective representation of the state and its uncertainty. Consider covariance analysis techniques provide a method to precompute a process noise covariance profile along a reference trajectory, using known model parameter uncertainties. The process noise covariance profile allows significantly improved state estimation and uncertainty representation over the traditional formulation. As a result, estimation performance on par with the consider filter is achieved for trajectories near the reference trajectory without the additional computational cost of the consider filter. The new formulation also has the potential to significantly reduce the trial-and-error tuning currently required of navigation analysts. A linear estimation problem as described in several previous consider covariance analysis publications is used to demonstrate the effectiveness of the precomputed process noise covariance, as well as a nonlinear descent scenario at the asteroid Bennu with optical navigation.
Spyropoulos, Evangelos; Kotsiris, Dimitrios; Spyropoulos, Katherine; Panagopoulos, Aggelos; Galanakis, Ioannis; Mavrikos, Stamatios
2017-02-01
We developed a mathematical "prostate cancer (PCa) conditions simulating" predictive model (PCP-SMART), from which we derived a novel PCa predictor (prostate cancer risk determinator [PCRD] index) and a PCa risk equation. We used these to estimate the probability of finding PCa on prostate biopsy, on an individual basis. A total of 371 men who had undergone transrectal ultrasound-guided prostate biopsy were enrolled in the present study. Given that PCa risk relates to the total prostate-specific antigen (tPSA) level, age, prostate volume, free PSA (fPSA), fPSA/tPSA ratio, and PSA density and that tPSA ≥ 50 ng/mL has a 98.5% positive predictive value for a PCa diagnosis, we hypothesized that correlating 2 variables composed of 3 ratios (1, tPSA/age; 2, tPSA/prostate volume; and 3, fPSA/tPSA; 1 variable including the patient's tPSA and the other, a tPSA value of 50 ng/mL) could operate as a PCa conditions imitating/simulating model. Linear regression analysis was used to derive the coefficient of determination (R 2 ), termed the PCRD index. To estimate the PCRD index's predictive validity, we used the χ 2 test, multiple logistic regression analysis with PCa risk equation formation, calculation of test performance characteristics, and area under the receiver operating characteristic curve analysis using SPSS, version 22 (P < .05). The biopsy findings were positive for PCa in 167 patients (45.1%) and negative in 164 (44.2%). The PCRD index was positively signed in 89.82% positive PCa cases and negative in 91.46% negative PCa cases (χ 2 test; P < .001; relative risk, 8.98). The sensitivity was 89.8%, specificity was 91.5%, positive predictive value was 91.5%, negative predictive value was 89.8%, positive likelihood ratio was 10.5, negative likelihood ratio was 0.11, and accuracy was 90.6%. Multiple logistic regression revealed the PCRD index as an independent PCa predictor, and the formulated risk equation was 91% accurate in predicting the probability of finding PCa. On the receiver operating characteristic analysis, the PCRD index (area under the curve, 0.926) significantly (P < .001) outperformed other, established PCa predictors. The PCRD index effectively predicted the prostate biopsy outcome, correctly identifying 9 of 10 men who were eventually diagnosed with PCa and correctly ruling out PCa for 9 of 10 men who did not have PCa. Its predictive power significantly outperformed established PCa predictors, and the formulated risk equation accurately calculated the probability of finding cancer on biopsy, on an individual patient basis. Copyright © 2016 Elsevier Inc. All rights reserved.
Park, Bumsoo; Choo, Seol Ho; Jeon, Hwang Gyun; Jeong, Byong Chang; Seo, Seong Il; Jeon, Seong Soo; Lee, Hyun Moo; Choi, Han Yong
2014-12-01
Traditionally, urologists recommend an interval of at least 4 weeks after prostate biopsy before radical prostatectomy. The aim of our study was to evaluate whether the interval from prostate biopsy to radical prostatectomy affects immediate operative outcomes, with a focus on differences in surgical approach. The study population of 1,848 radical prostatectomy patients was divided into two groups according to the surgical approach: open or minimally invasive. Open group included perineal and retropubic approach, and minimally invasive group included laparoscopic and robotic approach. The cut-off of the biopsy-to-surgery interval was 4 weeks. Positive surgical margin status, operative time and estimated blood loss were evaluated as endpoint parameters. In the open group, there were significant differences in operative time and estimated blood loss between the <4-week and ≥4-week interval subgroups, but there was no difference in positive margin rate. In the minimally invasive group, there were no differences in the three outcome parameters between the two subgroups. Multivariate analysis revealed that the biopsy-to-surgery interval was not a significant factor affecting immediate operative outcomes in both open and minimally invasive groups, with the exception of the interval ≥4 weeks as a significant factor decreasing operative time in the minimally invasive group. In conclusion, performing open or minimally invasive radical prostatectomy within 4 weeks of prostate biopsy is feasible for both approaches, and is even beneficial for minimally invasive radical prostatectomy to reduce operative time.
Markovina, Stephanie; Weschenfelder, Débora Cristina; Gay, Hiram; McCandless, Audrey; Carey, Bethany; DeWees, Todd; Knutson, Nels; Michalski, Jeff
2014-01-01
To evaluate serum testosterone and the incidence of biochemical hypogonadism in men treated with intensity modulated radiation therapy (IMRT) for prostate cancer. Serum testosterone was evaluated prospectively in 51 men at pretreatment and at 6-month time points for 2 years posttreatment with IMRT for prostate cancer. Forty-one patients (80%) were treated with definitive intent and 10 patients with postprostatectomy radiation to median total doses of 7380 cGy and 6480 cGy, respectively. No patients received hormone therapy within 12 months of any serum testosterone value. Biochemical hypogonadism was defined as a total serum testosterone level ≤ 300 ng/dL. Incidental testicular dose was calculated using planning software when computed tomography information was available (n = 21) and using a published method of estimation when not available (n = 24), and was available for 45 patients. A statistically significant decrease in testosterone, though small in magnitude, was seen at 6 months after completion of therapy, with no significant difference by 1 year after completion of therapy. There was no increase in biochemical hypogonadism after IMRT. Below-normal pretreatment testosterone was not associated with a transient decrease. Estimated cumulative testicular dose, including dose from daily imaging, was not associated with a change in testosterone, nor was radiation therapy prescription dose or treatment intent (postoperative vs definitive). The mild transient decrease in serum testosterone following IMRT monotherapy for prostate cancer is not associated with new biochemical hypogonadism.
Bayesian semiparametric estimation of covariate-dependent ROC curves
Rodríguez, Abel; Martínez, Julissa C.
2014-01-01
Receiver operating characteristic (ROC) curves are widely used to measure the discriminating power of medical tests and other classification procedures. In many practical applications, the performance of these procedures can depend on covariates such as age, naturally leading to a collection of curves associated with different covariate levels. This paper develops a Bayesian heteroscedastic semiparametric regression model and applies it to the estimation of covariate-dependent ROC curves. More specifically, our approach uses Gaussian process priors to model the conditional mean and conditional variance of the biomarker of interest for each of the populations under study. The model is illustrated through an application to the evaluation of prostate-specific antigen for the diagnosis of prostate cancer, which contrasts the performance of our model against alternative models. PMID:24174579
Abend, M; Badie, C; Quintens, R; Kriehuber, R; Manning, G; Macaeva, E; Njima, M; Oskamp, D; Strunz, S; Moertl, S; Doucha-Senf, S; Dahlke, S; Menzel, J; Port, M
2016-02-01
The risk of a large-scale event leading to acute radiation exposure necessitates the development of high-throughput methods for providing rapid individual dose estimates. Our work addresses three goals, which align with the directive of the European Union's Realizing the European Network of Biodosimetry project (EU-RENB): 1. To examine the suitability of different gene expression platforms for biodosimetry purposes; 2. To perform this examination using blood samples collected from prostate cancer patients (in vivo) and from healthy donors (in vitro); and 3. To compare radiation-induced gene expression changes of the in vivo with in vitro blood samples. For the in vitro part of this study, EDTA-treated whole blood was irradiated immediately after venipuncture using single X-ray doses (1 Gy/min(-1) dose rate, 100 keV). Blood samples used to generate calibration curves as well as 10 coded (blinded) samples (0-4 Gy dose range) were incubated for 24 h in vitro, lysed and shipped on wet ice. For the in vivo part of the study PAXgene tubes were used and peripheral blood (2.5 ml) was collected from prostate cancer patients before and 24 h after the first fractionated 2 Gy dose of localized radiotherapy to the pelvis [linear accelerator (LINAC), 580 MU/min, exposure 1-1.5 min]. Assays were run in each laboratory according to locally established protocols using either microarray platforms (2 laboratories) or qRT-PCR (2 laboratories). Report times on dose estimates were documented. The mean absolute difference of estimated doses relative to the true doses (Gy) were calculated. Doses were also merged into binary categories reflecting aspects of clinical/diagnostic relevance. For the in vitro part of the study, the earliest report time on dose estimates was 7 h for qRT-PCR and 35 h for microarrays. Methodological variance of gene expression measurements (CV ≤10% for technical replicates) and interindividual variance (≤twofold for all genes) were low. Dose estimates based on one gene, ferredoxin reductase (FDXR), using qRT-PCR were as precise as dose estimates based on multiple genes using microarrays, but the precision decreased at doses ≥2 Gy. Binary dose categories comprising, for example, unexposed compared with exposed samples, could be completely discriminated with most of our methods. Exposed prostate cancer blood samples (n = 4) could be completely discriminated from unexposed blood samples (n = 4, P < 0.03, two-sided Fisher's exact test) without individual controls. This could be performed by introducing an in vitro-to-in vivo correction factor of FDXR, which varied among the laboratories. After that the in vitro-constructed calibration curves could be used for dose estimation of the in vivo exposed prostate cancer blood samples within an accuracy window of ±0.5 Gy in both contributing qRT-PCR laboratories. In conclusion, early and precise dose estimates can be performed, in particular at doses ≤2 Gy in vitro. Blood samples of prostate cancer patients exposed to 0.09-0.017 Gy could be completely discriminated from pre-exposure blood samples with the doses successfully estimated using adjusted in vitro-constructed calibration curves.
NASA Technical Reports Server (NTRS)
Gay, Robert S.; Holt, Greg N.; Zanetti, Renato
2016-01-01
This paper details the post-flight navigation performance assessment of the Orion Exploration Flight Test-1 (EFT-1). Results of each flight phase are presented: Ground Align, Ascent, Orbit, and Entry Descent and Landing. This study examines the on-board Kalman Filter uncertainty along with state deviations relative to the Best Estimated Trajectory (BET). Overall the results show that the Orion Navigation System performed as well or better than expected. Specifically, the Global Positioning System (GPS) measurement availability was significantly better than anticipated at high altitudes. In addition, attitude estimation via processing GPS measurements along with Inertial Measurement Unit (IMU) data performed very well and maintained good attitude throughout the mission.
Thomsen, Frederik B; Berg, Kasper D; Røder, M Andreas; Iversen, Peter; Brasso, Klaus
2015-02-01
Evidence supports active surveillance (AS) as a means to reduce overtreatment of low-risk prostate cancer (PCa). The consequences of close and long-standing follow-up with regard to outpatient visits, tests and repeated biopsies are widely unknown. This study investigated the trajectory and costs of AS in patients with localized PCa. In total, 317 PCa patients were followed in a prospective, single-arm AS cohort. The primary outcomes were number of patient contacts, prostate-specific antigen (PSA) tests, biopsies, hospital admissions due to biopsy complications and patients eventually undergoing curative treatment. The secondary outcome was cost. The 5 year cumulative incidence of discontinued AS in a competing-risk model was 40%. During the first 5 years of AS patients underwent a median of two biopsy sets, and patients were seen in an outpatient clinic including PSA testing three to four times annually. In total, 38 of the 406 biopsy sessions led to hospital admission and 87 of the 317 patients required treatment for bladder outlet obstruction (BOO). With a median of 3.7 years' follow-up, the total cost of AS was euro (€) 1,240,286. Assuming all patients had otherwise undergone primary radical prostatectomy, the cost difference favoured AS with a net benefit of €662,661 (35% reduction). AS entails a close clinical follow-up with a considerable risk of rebiopsy complication, treatment of BOO and subsequent delayed definitive therapy. This risk should be weighed against a potential economic benefit and reduction in the risk of overtreatment compared to immediate radical treatment.
Fast T2*-weighted MRI of the prostate at 3 Tesla.
Hardman, Rulon L; El-Merhi, Fadi; Jung, Adam J; Ware, Steve; Thompson, Ian M; Friel, Harry T; Peng, Qi
2011-04-01
To describe a rapid T2*-weighted (T2*W), three-dimensional (3D) echo planar imaging (EPI) sequence and its application in mapping local magnetic susceptibility variations in 3 Tesla (T) prostate MRI. To compare the sensitivity of T2*W EPI with routinely used T1-weighted turbo-spin echo sequence (T1W TSE) in detecting hemorrhage and the implications on sequences sensitive to field inhomogeneities such as MR spectroscopy (MRS). B(0) susceptibility weighted mapping was performed using a 3D EPI sequence featuring a 2D spatial excitation pulse with gradients of spiral k-space trajectory. A series of 11 subjects were imaged using 3T MRI and combination endorectal (ER) and six-channel phased array cardiac coils. T1W TSE and T2*W EPI sequences were analyzed quantitatively for hemorrhage contrast. Point resolved spectroscopy (PRESS MRS) was performed and data quality was analyzed. Two types of susceptibility variation were identified: hemorrhagic and nonhemorrhagic T2*W-positive areas. Post-biopsy hemorrhage lesions showed on average five times greater contrast on the T2*W images than T1W TSE images. Six nonhemorrhage regions of severe susceptibility artifact were apparent on the T2*W images that were not seen on standard T1W or T2W images. All nonhemorrhagic susceptibility artifact regions demonstrated compromised spectral quality on 3D MRS. The fast T2*W EPI sequence identifies hemorrhagic and nonhemorrhagic areas of susceptibility variation that may be helpful in prostate MRI planning at 3.0T. Copyright © 2011 Wiley-Liss, Inc.
Variation in Trajectories of Women's Marital Quality
James, Spencer L.
2014-01-01
I examine variation in trajectories of women's marital quality across the life course. The analysis improves upon earlier research in three ways: (1) the analysis uses a sequential cohort design and data from the first 35 years of marriage; (2) I analyze rich data from a national sample; (3) I examine multiple dimensions of marital quality. Latent class growth analyses estimated on data from women in the National Longitudinal Survey of Youth-1979 (N = 2604) suggest multiple trajectories for each of three dimensions of marital quality, including two trajectories of marital happiness, two trajectories of marital communication, and three trajectories of marital conflict. Socioeconomic and demographic covariates are then used to illustrate how factors such as income, cohabitation, and race-ethnicity set individuals at risk of poor marital quality throughout the life course by differentiating between high and low trajectories of marital quality. Women on low marital quality trajectories are, as expected, at much greater risk of divorce. Taken together, these findings show how fundamental socioeconomic and demographic characteristics contribute to subsequent marital outcomes via their influence on trajectories of marital quality as well as providing a better picture of the complexity in contemporary patterns of marital quality. PMID:25432600
NASA Astrophysics Data System (ADS)
Guevara Hidalgo, Esteban; Nemoto, Takahiro; Lecomte, Vivien
Rare trajectories of stochastic systems are important to understand because of their potential impact. However, their properties are by definition difficult to sample directly. Population dynamics provide a numerical tool allowing their study, by means of simulating a large number of copies of the system, which are subjected to a selection rule that favors the rare trajectories of interest. However, such algorithms are plagued by finite simulation time- and finite population size- effects that can render their use delicate. Using the continuous-time cloning algorithm, we analyze the finite-time and finite-size scalings of estimators of the large deviation functions associated to the distribution of the rare trajectories. We use these scalings in order to propose a numerical approach which allows to extract the infinite-time and infinite-size limit of these estimators.
The General Mission Analysis Tool (GMAT): Current Features And Adding Custom Functionality
NASA Technical Reports Server (NTRS)
Conway, Darrel J.; Hughes, Steven P.
2010-01-01
The General Mission Analysis Tool (GMAT) is a software system for trajectory optimization, mission analysis, trajectory estimation, and prediction developed by NASA, the Air Force Research Lab, and private industry. GMAT's design and implementation are based on four basic principles: open source visibility for both the source code and design documentation; platform independence; modular design; and user extensibility. The system, released under the NASA Open Source Agreement, runs on Windows, Mac and Linux. User extensions, loaded at run time, have been built for optimization, trajectory visualization, force model extension, and estimation, by parties outside of GMAT's development group. The system has been used to optimize maneuvers for the Lunar Crater Observation and Sensing Satellite (LCROSS) and ARTEMIS missions and is being used for formation design and analysis for the Magnetospheric Multiscale Mission (MMS).
Vallo, Stefan; Gilfrich, Christian; Burger, Maximilian; Volkmer, Björn; Boehm, Katharina; Rink, Michael; Chun, Felix K; Roghmann, Florian; Novotny, Vladimir; Mani, Jens; Brisuda, Antonin; Mayr, Roman; Stredele, Regina; Noldus, Joachim; Schnabel, Marco; May, Matthias; Fritsche, Hans-Martin; Pycha, Armin; Martini, Thomas; Wirth, Manfred; Roigas, Jan; Bastian, Patrick J; Nuhn, Philipp; Dahlem, Roland; Haferkamp, Axel; Fisch, Margit; Aziz, Atiqullah
2016-10-01
To evaluate the prognostic relevance of different prostatic invasion patterns in pT4a urothelial carcinoma of the bladder (UCB) after radical cystectomy. Our study comprised a total of 358 men with pT4a UCB. Patients were divided in 2 groups-group A with stromal infiltration of the prostate via the prostatic urethra with additional muscle-invasive UCB (n = 121, 33.8%) and group B with continuous infiltration of the prostate through the entire bladder wall (n = 237, 66.2%). The effect of age, tumor grade, carcinoma in situ, lymphovascular invasion, soft tissue surgical margin, lymph node metastases, administration of adjuvant chemotherapy, and prostatic invasion patterns on cancer-specific mortality (CSM) was evaluated using competing-risk regression analysis. Decision curve analysis was used to evaluate the net benefit of including the variable invasion pattern within our model. The estimated 5-year CSM-rates for group A and B were 50.1% and 66.0%, respectively. In multivariable competing-risk analysis, lymph node metastases (hazard ratio [HR] = 1.73, P<0.001), lymphovascular invasion (HR = 1.62, P = 0.0023), soft tissue surgical margin (HR = 1.49, P = 0.026), absence of adjuvant chemotherapy (HR = 2.11, P<0.001), and tumor infiltration of the prostate by continuous infiltration of the entire bladder wall (HR = 1.37, P = 0.044) were significantly associated with a higher risk for CSM. Decision curve analysis showed a net benefit of our model including the variable invasion pattern. Continuous infiltration of the prostate through the entire bladder wall showed an adverse effect on CSM. Besides including these patients into clinical trials for an adjuvant therapy, we recommend including prostatic invasion patterns in predictive models in pT4a UCB in men. Copyright © 2016 Elsevier Inc. All rights reserved.
Taylor, Amy E; Martin, Richard M; Geybels, Milan S; Stanford, Janet L; Shui, Irene; Eeles, Rosalind; Easton, Doug; Kote-Jarai, Zsofia; Amin Al Olama, Ali; Benlloch, Sara; Muir, Kenneth; Giles, Graham G; Wiklund, Fredrik; Gronberg, Henrik; Haiman, Christopher A; Schleutker, Johanna; Nordestgaard, Børge G; Travis, Ruth C; Neal, David; Pashayan, Nora; Khaw, Kay-Tee; Blot, William; Thibodeau, Stephen; Maier, Christiane; Kibel, Adam S; Cybulski, Cezary; Cannon-Albright, Lisa; Brenner, Hermann; Park, Jong; Kaneva, Radka; Batra, Jyotsna; Teixeira, Manuel R; Pandha, Hardev; Donovan, Jenny; Munafò, Marcus R
2017-01-15
Coffee consumption has been shown in some studies to be associated with lower risk of prostate cancer. However, it is unclear if this association is causal or due to confounding or reverse causality. We conducted a Mendelian randomisation analysis to investigate the causal effects of coffee consumption on prostate cancer risk and progression. We used two genetic variants robustly associated with caffeine intake (rs4410790 and rs2472297) as proxies for coffee consumption in a sample of 46,687 men of European ancestry from 25 studies in the PRACTICAL consortium. Associations between genetic variants and prostate cancer case status, stage and grade were assessed by logistic regression and with all-cause and prostate cancer-specific mortality using Cox proportional hazards regression. There was no clear evidence that a genetic risk score combining rs4410790 and rs2472297 was associated with prostate cancer risk (OR per additional coffee increasing allele: 1.01, 95% CI: 0.98,1.03) or having high-grade compared to low-grade disease (OR: 1.01, 95% CI: 0.97,1.04). There was some evidence that the genetic risk score was associated with higher odds of having nonlocalised compared to localised stage disease (OR: 1.03, 95% CI: 1.01, 1.06). Amongst men with prostate cancer, there was no clear association between the genetic risk score and all-cause mortality (HR: 1.00, 95% CI: 0.97,1.04) or prostate cancer-specific mortality (HR: 1.03, 95% CI: 0.98,1.08). These results, which should have less bias from confounding than observational estimates, are not consistent with a substantial effect of coffee consumption on reducing prostate cancer incidence or progression. © 2016 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Viraganathan, H; Jiang, R; Chow, J
Purpose: We proposed a method to predict the change of dose-volume histogram (DVH) for PTV due to patient weight loss in prostate volumetric modulated arc therapy (VMAT). This method is based on a pre-calculated patient dataset and DVH curve fitting using the Gaussian error function (GEF). Methods: Pre-calculated dose-volume data from patients having weight loss in prostate VMAT was employed to predict the change of PTV coverage due to reduced depth in external contour. The effect of patient weight loss in treatment was described by a prostate dose-volume factor (PDVF), which was evaluated by the prostate PTV. Along with themore » PDVF, the GEF was used to fit into the DVH curve for the PTV. To predict a new DVH due to weight loss, parameters from the GEF describing the shape of DVH curve were determined. Since the parameters were related to the PDVF as per the specific reduced depth, we could first predict the PDVF at a reduced depth based on the prostate size from the pre-calculated dataset. Then parameters of the GEF could be determined from the PDVF to plot the new DVH for the PTV corresponding to the reduced depth. Results: A MATLAB program was built basing on the patient dataset with different prostate sizes. We input data of the prostate size and reduced depth of the patient into the program. The program then calculated the PDVF and DVH for the PTV considering the patient weight loss. The program was verified by different patient cases with various reduced depths. Conclusion: Our method can estimate the change of DVH for the PTV due to patient weight loss quickly without CT rescan and replan. This would help the radiation staff to predict the change of PTV coverage, when patient’s external contour reduced in prostate VMAT.« less
Aly, Markus; Dyrdak, Robert; Nordström, Tobias; Jalal, Shah; Weibull, Caroline E; Giske, Christian G; Grönberg, Henrik
2015-06-15
Bloodstream infection following a transrectal prostate biopsy is a well-known and feared complication. Previous studies have shown an increase in multi-resistant bacterial infections as a consequence of higher usage of antibiotics in investigated populations. Our aim was to analyze bacterial resistance patterns in positive blood cultures, after prostate biopsies in Stockholm, Sweden, where the use of antibiotics has been low and decreasing during the last 10 years. From the three pathology laboratories in Stockholm, reports of prostate examinations were retrieved (n = 56,076) from 2003 to 2012. By linking men to the National Patient Register all but prostate core biopsies were excluded (n = 12,024). Prostate biopsies in men younger than 30 years of age were excluded (n = 5) leaving 44,047 biopsies for analysis. From laboratory information systems data regarding blood cultures were retrieved. Proportions of blood cultures within 30 days by year were calculated. Crude and adjusted logistic regression models were used to estimate ORs. In total, 44,047 prostate biopsies were performed in 32,916 men over 10 years. On 620 occasions a blood culture was drawn within 30 days of the biopsy; 266 of these were positive. The proportions with positive blood cultures in 2003 and 2012 were 0.38 and 1.14%, respectively. The proportion of multidrug-resistant bacteria increased significantly during the study. In the crude and the adjusted analysis, the year of biopsy and Charlson Comorbidity Index were associated with the risk of having a positive blood culture. Multidrug-resistant enteric bacilli are becoming a problem in Sweden, despite low antimicrobial use. Men need to be informed about the increasing risks of infectious complications of transrectal prostate biopsy. One out of 50 men undergoing a prostate biopsy will develop symptoms suggestive of a bloodstream infection after the biopsy and one in 100 men will have a positive blood culture. © 2015 Wiley Periodicals, Inc.
Coupled Inertial Navigation and Flush Air Data Sensing Algorithm for Atmosphere Estimation
NASA Technical Reports Server (NTRS)
Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberger, Mark
2015-01-01
This paper describes an algorithm for atmospheric state estimation that is based on a coupling between inertial navigation and flush air data sensing pressure measurements. In this approach, the full navigation state is used in the atmospheric estimation algorithm along with the pressure measurements and a model of the surface pressure distribution to directly estimate atmospheric winds and density using a nonlinear weighted least-squares algorithm. The approach uses a high fidelity model of atmosphere stored in table-look-up form, along with simplified models of that are propagated along the trajectory within the algorithm to provide prior estimates and covariances to aid the air data state solution. Thus, the method is essentially a reduced-order Kalman filter in which the inertial states are taken from the navigation solution and atmospheric states are estimated in the filter. The algorithm is applied to data from the Mars Science Laboratory entry, descent, and landing from August 2012. Reasonable estimates of the atmosphere and winds are produced by the algorithm. The observability of winds along the trajectory are examined using an index based on the discrete-time observability Gramian and the pressure measurement sensitivity matrix. The results indicate that bank reversals are responsible for adding information content to the system. The algorithm is then applied to the design of the pressure measurement system for the Mars 2020 mission. The pressure port layout is optimized to maximize the observability of atmospheric states along the trajectory. Linear covariance analysis is performed to assess estimator performance for a given pressure measurement uncertainty. The results indicate that the new tightly-coupled estimator can produce enhanced estimates of atmospheric states when compared with existing algorithms.
Nderitu, Paul; Van Hemelrijck, Mieke; Ashworth, Mark; Mathur, Rohini; Hull, Sally; Dudek, Alexandra; Chowdhury, Simon
2016-07-12
To investigate the association between factors influencing prostate-specific antigen (PSA) testing prevalence including prostate cancer risk factors (age, ethnicity, obesity) and non-risk factors (social deprivation and comorbidity). A cross-sectional database of 136 inner London general practices from 1 August 2009 to 31 July 2014. Men aged ≥40 years without prostate cancer were included (n=150 481). Logistic regression analyses were used to estimate the association between PSA testing and age, ethnicity, social deprivation, body mass index (BMI) and comorbidity while adjusting for age, benign prostatic hypertrophy, prostatitis and tamsulosin or finasteride use. PSA testing prevalence was 8.2% (2013-2014), and the mean age was 54 years (SD 11). PSA testing was positively associated with age (OR 70-74 years compared to 40-44 years: 7.34 (95% CI 6.82 to 7.90)), ethnicity (black) (OR compared to white: 1.78 (95% CI 1.71 to 1.85)), increasing BMI and cardiovascular comorbidity. Testing was negatively associated with Chinese ethnicity and with increasing social deprivation. PSA testing among black patients was higher compared to that among white patients, which differs from lower testing rates seen in previous studies. PSA testing was positively associated with prostate cancer risk factors and non-risk factors. Association with non-risk factors may increase the risk of unnecessary invasive diagnostic procedures. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Cary, C; Odisho, A Y; Cooperberg, M R
2016-06-01
We sought to assess variation in the primary treatment of prostate cancer by examining the effect of population density of the county of residence on treatment for clinically localized prostate cancer and quantify variation in primary treatment attributable to the county and state level. A total 138 226 men with clinically localized prostate cancer in the Surveillance, Epidemiology and End Result (SEER) database in 2005 through 2008 were analyzed. The main association of interest was between prostate cancer treatment and population density using multilevel hierarchical logit models while accounting for the random effects of counties nested within SEER regions. To quantify the effect of county and SEER region on individual treatment, the percent of total variance in treatment attributable to county of residence and SEER site was estimated with residual intraclass correlation coefficients. Men with localized prostate cancer in metropolitan counties had 23% higher odds of being treated with surgery or radiation compared with men in rural counties, controlling for number of urologists per county as well as clinical and sociodemographic characteristics. Three percent (95% confidence interval (CI): 1.2-6.2%) of the total variation in treatment was attributable to SEER site, while 6% (95% CI: 4.3-9.0%) of variation was attributable to county of residence, adjusting for clinical and sociodemographic characteristics. Variation in treatment for localized prostate cancer exists for men living in different population-dense counties of the country. These findings highlight the importance of comparative effectiveness research to improve understanding of this variation and lead to a reduction in unwarranted variation.
Bhaskaran, Natarajan; Gupta, Sanjay
2014-01-01
Oxidative stress has been linked to prostate carcinogenesis as human prostate tissue is vulnerable to oxidative DNA damage. Apigenin, a dietary plant flavone, possesses anti-proliferative and anticancer effects; however, its antioxidant properties have not been fully elucidated. We investigated sub-cellular distribution of apigenin, it’s binding to DNA and protective effects against H2O2-induced DNA damage using transformed human prostate epithelial RWPE-1 cells and prostate cancer LNCaP, PC-3 and DU145 cells. Exposure of cells to apigenin exhibited higher accumulation in RWPE-1 and LNCaP cells, compared to PC-3 and DU145 cells. The kinetics of apigenin uptake in LNCaP cells was estimated with a Km value of 5 µmole/L and Vmax of 190 pmoles/million cells/h. Sub-cellular fractionation demonstrated that nuclear matrix retains the highest concentration of apigenin (45.3%), followed by cytosol (23.9%), nuclear membranes (17.9%) and microsomes (12.9%), respectively. Spectroscopic analysis of apigenin with calf-thymus DNA exhibited intercalation as the dominant binding mode to DNA duplex. Apigenin exposure resulted in significant genoprotective effects in H2O2-stressed RWPE-1 cells by reduction in reactive oxygen species levels. In addition, apigenin exposure suppressed the formation of 8-hydroxy-2′ deoxyguanosine and protected exposed cells from apoptosis. Our studies demonstrate that apigenin is readily taken up by normal prostatic epithelial cells and prostate cancer cells, and is incorporated into their nuclei, where its intercalation with nucleic acid bases may account for its antioxidant and chemopreventive activities. PMID:24614817
Chua, Michael E.; Sio, Maria Christina D.; Sorongon, Mishell C.; Morales, Marcelino L.
2013-01-01
Objective: Our objective was to systematically analyze the evidence for an association between serum level long chain omega-3 polyunsaturated fatty acid (n-3 PUFA) and prostate cancer risk from human epidemiological studies. Study Procedures: We searched biomedical literature databases up to November 2011 and included epidemiological studies with description of long chain n-3 PUFA and incidence of prostate cancer in humans. Critical appraisal was done by two independent reviewers. Data were pooled using the general variance-based method with random-effects model; effect estimates were expressed as risk ratio with 95% confidence interval (CI). Heterogeneity was assessed by Chi2 and quantified by I2, publication bias was also determined. Results: In total, 12 studies were included. Significant negative association was noted between high serum level of n-3 PUFA doc-osapentaenoic acid (DPA) and total prostate cancer risk (RR:0.756; 95% CI 0.599, 0.955; p = 0.019). Likewise, a positive association between high blood level of fish oil contents, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and high-grade prostate tumour incidence (RR:1.381; 95% CI 1.050, 1.817; p = 0.021) was noted; however, this finding was evident only after adjustment was done on interstudy variability through the removal of a lower quality study from the pool. Conclusions: High serum levels of long chain n-3 PUFA DPA is associated with reduced total prostate cancer risk. While high blood level of EPA and DHA is possibly associated with increased high-grade prostate tumour risk. PMID:23766835
Sharma, Haripaul; Kanwal, Rajnee; Bhaskaran, Natarajan; Gupta, Sanjay
2014-01-01
Oxidative stress has been linked to prostate carcinogenesis as human prostate tissue is vulnerable to oxidative DNA damage. Apigenin, a dietary plant flavone, possesses anti-proliferative and anticancer effects; however, its antioxidant properties have not been fully elucidated. We investigated sub-cellular distribution of apigenin, it's binding to DNA and protective effects against H2O2-induced DNA damage using transformed human prostate epithelial RWPE-1 cells and prostate cancer LNCaP, PC-3 and DU145 cells. Exposure of cells to apigenin exhibited higher accumulation in RWPE-1 and LNCaP cells, compared to PC-3 and DU145 cells. The kinetics of apigenin uptake in LNCaP cells was estimated with a Km value of 5 µmole/L and Vmax of 190 pmoles/million cells/h. Sub-cellular fractionation demonstrated that nuclear matrix retains the highest concentration of apigenin (45.3%), followed by cytosol (23.9%), nuclear membranes (17.9%) and microsomes (12.9%), respectively. Spectroscopic analysis of apigenin with calf-thymus DNA exhibited intercalation as the dominant binding mode to DNA duplex. Apigenin exposure resulted in significant genoprotective effects in H2O2-stressed RWPE-1 cells by reduction in reactive oxygen species levels. In addition, apigenin exposure suppressed the formation of 8-hydroxy-2' deoxyguanosine and protected exposed cells from apoptosis. Our studies demonstrate that apigenin is readily taken up by normal prostatic epithelial cells and prostate cancer cells, and is incorporated into their nuclei, where its intercalation with nucleic acid bases may account for its antioxidant and chemopreventive activities.
Dwivedi, Shailendra; Goel, Apul; Natu, Shanker M; Mandhani, Anil; Khattri, Sanjay; Pant, Kamlesh K
2011-01-01
Prostate cancer is one of the most common cancers afflicting men today. Prostate biopsy, an invasive procedure is generally used for diagnoses but attempts are being made to find accurate and precise non-invasive biomarkers. Diagnostic accuracy of prostate specific antigen (PSA) has been well documented. Serum interleukin-18 (IL-18) and interleukin-10 (IL-10) have shown their diagnostic ability in other cancers but not investigated well in prostate cancer. This study, thus determines the diagnostic and prognostic significance of PSA, IL-18 and IL-10 prospectively in patients with carcinoma prostate. A total of 149 patients, aged 40-84 yrs were investigated during April 2007 to July 2010 and recruited for this study after Institutional ethical approval. Of the total of 149 patients, 71 had biopsy proven prostate cancers (TNM stage: T2=17, T3=26 and T4=28) and 78 clinical benign prostate hyperplasia (BPH). Peripheral blood samples of all patients and 71 age matched control subjects were obtained at baseline and estimation of PSA, IL-18 and IL-10 was done by enzyme linked immunosorbent assay (ELISA). Carcinoma prostate patients were followed for three years. Data were analyzed with ANOVA, ROC curve analysis and survival analysis. The baseline levels of PSA, IL-18 and IL-10 in all groups of carcinoma prostate were found to be significantly (p<0.01) higher than both Control and BPH. The levels of IL-18 and IL-10 also found to be elevated significantly in stage T3 (p<0.05) and T4 (p<0.01) as compared to stage T2. The levels especially of IL-18 is found to be well associated with progression of the disease of various groups (r=0.84, p<0.01). In contrast, IL-10 showed significant direct association with progression of carcinoma (r=0.84, p<0.01) while inverse relation with survival duration (r=-0.48, p<0.01) and survival rate (χ2=8.98, p=0.0027; Hazard ratio=0.37, 95% CI=0.18-0.69). Study concluded that serum IL-18 has potential to be a better diagnostic marker with higher specificity and sensitivity and IL-10 may be valuable as a prognostic marker than PSA in carcinoma prostate.
Alcohol consumption and PSA-detected prostate cancer risk—A case-control nested in the ProtecT study
Zuccolo, Luisa; Lewis, Sarah J; Donovan, Jenny L; Hamdy, Freddie C; Neal, David E; Smith, George Davey
2013-01-01
Alcohol is an established carcinogen but not an established risk factor for prostate cancer, despite some recent prospective studies suggesting increased risk among heavy drinkers. The aim of this study was to investigate the role of alcohol on prostate-specific antigen (PSA) levels and prostate cancer risk. Two thousand four hundred PSA detected prostate cancer cases and 12,700 controls matched on age and general practice were identified through a case-control study nested in the PSA-testing phase of a large UK-based randomized controlled trial for prostate cancer treatment (ProtecT). Linear and multinomial logistic regression models were used to estimate ratios of geometric means (RGMs) of PSA and relative risk ratios (RRRs) of prostate cancer by stage and grade, with 95% confidence intervals (CIs), associated with weekly alcohol intake and drinking patterns. We found evidence of lower PSA (RGM 0.98, 95% CI: 0.98–0.99) and decreased risk of low Gleason-grade (RRR 0.96; 95%CI 0.93–0.99) but increased risk of high-grade prostate cancer (RRR 1.04; 95%CI 0.99–1.08; pdifference=0.004) per 10 units/week increase in alcohol consumption, not explained by current BMI, blood pressure, comorbidities, or reverse causation. This is the first large population-based study to find evidence of lower PSA levels for increasing alcohol consumption, with potential public health implications for the detection of prostate cancer. Our results also support a modestly higher risk of high-grade disease for heavy drinkers, but require independent replication to establish the nature of the association of alcohol with low-grade disease, preferably in cohorts with a heterogeneous case-mix. What's new? Alcohol is not an established risk factor for prostate cancer; however, the current work suggests that heavy drinking could cause a small increase in risk of the more aggressive forms. If the results are confirmed to be causal, prostate cancer risk will be added to the many long-term health risks of heavy drinking, and public health strategies will then also reduce high-risk, poorer prognosis prostate cancer. The authors also found that heavy drinkers have lower PSA levels, suggesting that heavy alcohol consumption could be used as a marker to identify men in whom some cancers might be missed. PMID:23024014
Ultrasound-contrast-agent dispersion and velocity imaging for prostate cancer localization.
van Sloun, Ruud Jg; Demi, Libertario; Postema, Arnoud W; de la Rosette, Jean Jmch; Wijkstra, Hessel; Mischi, Massimo
2017-01-01
Prostate cancer (PCa) is the second-leading cause of cancer death in men; however, reliable tools for detection and localization are still lacking. Dynamic Contrast Enhanced UltraSound (DCE-US) is a diagnostic tool that is suitable for analysis of vascularization, by imaging an intravenously injected microbubble bolus. The localization of angiogenic vascularization associated with the development of tumors is of particular interest. Recently, methods for the analysis of the bolus convective dispersion process have shown promise to localize angiogenesis. However, independent estimation of dispersion was not possible due to the ambiguity between convection and dispersion. Therefore, in this study we propose a new method that considers the vascular network as a dynamic linear system, whose impulse response can be locally identified. To this end, model-based parameter estimation is employed, that permits extraction of the apparent dispersion coefficient (D), velocity (v), and Péclet number (Pe) of the system. Clinical evaluation using data recorded from 25 patients shows that the proposed method can be applied effectively to DCE-US, and is able to locally characterize the hemodynamics, yielding promising results (receiver-operating-characteristic curve area of 0.84) for prostate cancer localization. Copyright © 2016 Elsevier B.V. All rights reserved.
Li, Shuting; Shi, Min; Zhao, Jingjin; Zhang, Liangliang; Huang, Yong; Zhao, Shulin
2017-07-01
An enzyme and antibody dual labeled gold nanoparticles enhancing chemiluminescence strategy was developed for highly sensitive CE immunoassay (IA) of prostate-specific antigen (PSA). In this work, gold nanoparticles were labeled with horseradish peroxidase and antiprostate specific antigen-antibody, and used as the marker (Ab * ). After PSA (antigen, Ag) was added into the system, a noncompetitive immune reaction was happen between Ab * and Ag to form an immune complex (Ag-Ab * ). Subsequently, the obtained Ag-Ab * and unreacted Ab * were separated by CE, and the chemiluminescence intensity of Ag-Ab * was used to estimate PSA concentration. The calibration curve showed a good linearity in the range of 0.25-10 ng/mL. Based on a S/N of 3, the detection limit for PAS was estimated to be 0.092 ng/mL. Proposed CE method was applied for PSA quantification in human serum samples from healthy volunteers and patients with prostate cancer. The obtained results demonstrated that the proposed CE method may serve as an alternative tool for clinical analysis of PSA. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Insaf, Tabassum Z; Shaw, Benjamin A; Yucel, Recai M; Chasan-Taber, Lisa; Strogatz, David S
2014-01-01
Objective To evaluate the association between lifecourse socioeconomic position (SEP) and changes in body mass index (BMI), and assess disparities in these associations across racial/ethnic groups. Methods With longitudinal data from 4 waves of the Americans Changing Lives Study (1986–2002), we employed mixed-effects modeling to estimate BMI trajectories for 1,174 Blacks and 2,323 White adults. We also estimated associations between these trajectories and lifecourse SEP variables, including father’s education, perceived childhood SEP, own education, income, wealth, and financial security. Results Blacks had higher baseline BMI’s, and steeper increases in BMI, compared to Whites. Childhood SEP, as measured by high father’s education, was associated with lower baseline BMI among Whites. High education was associated with a lower baseline BMI within both race and sex categories. Income had contrasting effects among men and women. Higher income, was associated with higher BMI only among males Associations between indicators of SEP and BMI trajectories were only found for Whites. Conclusions Our study demonstrates that lifecourse SEP may influence adult BMI differently within different racial and sex groups. PMID:24967954
An online x-ray based position validation system for prostate hypofractionated radiotherapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arumugam, Sankar, E-mail: Sankar.Arumugam@sswahs.nsw.gov.au; Xing, Aitang; Sidhom, Mark
Purpose: Accurate positioning of the target volume during treatment is paramount for stereotactic body radiation therapy (SBRT). In this work, the authors present the development of an in-house software tool to verify target position with an Elekta-Synergy linear accelerator using kV planar images acquired during treatment delivery. Methods: In-house software, SeedTracker, was developed in MATLAB to perform the following three functions: 1. predict intended seed positions in a planar view perpendicular to any gantry angle, simulating a portal imaging device, from the 3D seed co-ordinates derived from the treatment planning system; 2. autosegment seed positions in kV planar images; andmore » 3. report the position shift based on the seed positions in the projection images. The performance of SeedTracker was verified using a CIRS humanoid phantom (CIRS, VA, USA) implanted with three Civco gold seed markers (Civco, IA, USA) in the prostate. The true positive rate of autosegmentation (TPR{sub seg}) and the accuracy of the software in alerting the user when the isocenter position was outside the tolerance (TPR{sub trig}) were studied. Two-dimensional and 3D static position offsets introduced to the humanoid phantom and 3D dynamic offsets introduced to a gel phantom containing gold seeds were used for evaluation of the system. Results: SeedTracker showed a TPR{sub seg} of 100% in the humanoid phantom for projection images acquired at all angles except in the ranges of 80°–100° and 260°–280° where seeds are obscured by anatomy. This resulted in a TPR{sub trig} of 88% over the entire treatment range for considered 3D static offsets introduced to the phantom. For 2D static offsets where the position offsets were only introduced in the anterior–posterior and lateral directions, the TPR{sub trig} of SeedTracker was limited by both seed detectability and positional offset. SeedTracker showed a false positive trigger in the projection angle range between 130°–170° and 310°–350° (a maximum of 24% of treatment time) due to limited information that can be derived from monoscopic images. The system accurately determined the dynamic trajectory of the isocenter position in the superior and inferior direction for the studied dynamic offset scenarios based on the seed position in monoscopic images. Conclusions: The developed software has been shown to accurately autosegment the seed positions in kV planar images except for two 20° arcs where seeds are obscured by anatomical structures. The isocenter trajectories determined by the system, based on the monoscopic images, provide useful information for monitoring the prostate position. The developed system has potential application for monitoring prostate position during treatment delivery in linear accelerator based SBRT.« less
Electromagnetic guided couch and multileaf collimator tracking on a TrueBeam accelerator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Rune; Ravkilde, Thomas; Worm, Esben Schjødt
2016-05-15
Purpose: Couch and MLC tracking are two promising methods for real-time motion compensation during radiation therapy. So far, couch and MLC tracking experiments have mainly been performed by different research groups, and no direct comparison of couch and MLC tracking of volumetric modulated arc therapy (VMAT) plans has been published. The Varian TrueBeam 2.0 accelerator includes a prototype tracking system with selectable couch or MLC compensation. This study provides a direct comparison of the two tracking types with an otherwise identical setup. Methods: Several experiments were performed to characterize the geometric and dosimetric performance of electromagnetic guided couch and MLCmore » tracking on a TrueBeam accelerator equipped with a Millennium MLC. The tracking system latency was determined without motion prediction as the time lag between sinusoidal target motion and the compensating motion of the couch or MLC as recorded by continuous MV portal imaging. The geometric and dosimetric tracking accuracies were measured in tracking experiments with motion phantoms that reproduced four prostate and four lung tumor trajectories. The geometric tracking error in beam’s eye view was determined as the distance between an embedded gold marker and a circular MLC aperture in continuous MV images. The dosimetric tracking error was quantified as the measured 2%/2 mm gamma failure rate of a low and a high modulation VMAT plan delivered with the eight motion trajectories using a static dose distribution as reference. Results: The MLC tracking latency was approximately 146 ms for all sinusoidal period lengths while the couch tracking latency increased from 187 to 246 ms with decreasing period length due to limitations in the couch acceleration. The mean root-mean-square geometric error was 0.80 mm (couch tracking), 0.52 mm (MLC tracking), and 2.75 mm (no tracking) parallel to the MLC leaves and 0.66 mm (couch), 1.14 mm (MLC), and 2.41 mm (no tracking) perpendicular to the leaves. The motion-induced gamma failure rate was in mean 0.1% (couch tracking), 8.1% (MLC tracking), and 30.4% (no tracking) for prostate motion and 2.9% (couch), 2.4% (MLC), and 41.2% (no tracking) for lung tumor motion. The residual tracking errors were mainly caused by inadequate adaptation to fast lung tumor motion for couch tracking and to prostate motion perpendicular to the MLC leaves for MLC tracking. Conclusions: Couch and MLC tracking markedly improved the geometric and dosimetric accuracies of VMAT delivery. However, the two tracking types have different strengths and weaknesses. While couch tracking can correct perfectly for slowly moving targets such as the prostate, MLC tracking may have considerably larger dose errors for persistent target shift perpendicular to the MLC leaves. Advantages of MLC tracking include faster dynamics with better adaptation to fast moving targets, the avoidance of moving the patient, and the potential to track target rotations and deformations.« less
NASA Astrophysics Data System (ADS)
Vorotnikov, A. A.; Klimov, D. D.; Romash, E. V.; Bashevskaya, O. S.; Poduraev, Yu. V.; Bazykyan, E. A.; Chunihin, A. A.
2018-03-01
Industrial robots perform technological operations, such as spot and arc welding, machining and laser cutting along different trajectories within their performance characteristics. The evaluation of these characteristics is carried out according to the criteria of the standard ISO 9283. The criteria of this standard are applicable in industrial manufacturing, but not in the medical industry, as they are not developed in the framework of medical tasks. Therefore, it is necessary to evaluate according to criteria built on different principles. In this article, the question of comparative evaluation of trajectories from program movements of a robot and manual movements of a surgeon, arising during the development of robotic medical complexes using industrial robots, is considered. A comparative evaluation is required to prove the expediency of automating medical operations in maxillofacial surgery. This study focuses on the estimation of velocity accuracy of a medical instrument. To obtain the velocity of the medical instrument, coordinates of the trajectory points from the program movements of the robot KUKA LWR4+ and trajectories from the manual movements of a professional surgeon have been measured. The measurement was carried out using a coordinate measuring machine, the laser tracker Leica LTD800. The accuracy estimation was carried out by two criteria: the criterion set out in the ISO 9283 standard, and the developed alternative criterion, the description of which is presented in this article. A quantitative comparative evaluation of the trajectories of a robot and a surgeon was obtained.
Photogrammetric Trajectory Estimation of Foam Debris Ejected From an F-15 Aircraft
NASA Technical Reports Server (NTRS)
Smith, Mark S.
2006-01-01
Photogrammetric analysis of high-speed digital video data was performed to estimate trajectories of foam debris ejected from an F-15B aircraft. This work was part of a flight test effort to study the transport properties of insulating foam shed by the Space Shuttle external tank during ascent. The conical frustum-shaped pieces of debris, called "divots," were ejected from a flight test fixture mounted underneath the F-15B aircraft. Two onboard cameras gathered digital video data at two thousand frames per second. Time histories of divot positions were determined from the videos post flight using standard photogrammetry techniques. Divot velocities were estimated by differentiating these positions with respect to time. Time histories of divot rotations were estimated using four points on the divot face. Estimated divot position, rotation, and Mach number for selected cases are presented. Uncertainty in the results is discussed.
NASA Astrophysics Data System (ADS)
Meng, Deyuan; Tao, Guoliang; Liu, Hao; Zhu, Xiaocong
2014-07-01
Friction compensation is particularly important for motion trajectory tracking control of pneumatic cylinders at low speed movement. However, most of the existing model-based friction compensation schemes use simple classical models, which are not enough to address applications with high-accuracy position requirements. Furthermore, the friction force in the cylinder is time-varying, and there exist rather severe unmodelled dynamics and unknown disturbances in the pneumatic system. To deal with these problems effectively, an adaptive robust controller with LuGre model-based dynamic friction compensation is constructed. The proposed controller employs on-line recursive least squares estimation (RLSE) to reduce the extent of parametric uncertainties, and utilizes the sliding mode control method to attenuate the effects of parameter estimation errors, unmodelled dynamics and disturbances. In addition, in order to realize LuGre model-based friction compensation, the modified dual-observer structure for estimating immeasurable friction internal state is developed. Therefore, a prescribed motion tracking transient performance and final tracking accuracy can be guaranteed. Since the system model uncertainties are unmatched, the recursive backstepping design technology is applied. In order to solve the conflicts between the sliding mode control design and the adaptive control design, the projection mapping is used to condition the RLSE algorithm so that the parameter estimates are kept within a known bounded convex set. Finally, the proposed controller is tested for tracking sinusoidal trajectories and smooth square trajectory under different loads and sudden disturbance. The testing results demonstrate that the achievable performance of the proposed controller is excellent and is much better than most other studies in literature. Especially when a 0.5 Hz sinusoidal trajectory is tracked, the maximum tracking error is 0.96 mm and the average tracking error is 0.45 mm. This paper constructs an adaptive robust controller which can compensate the friction force in the cylinder.
Effects of camera location on the reconstruction of 3D flare trajectory with two cameras
NASA Astrophysics Data System (ADS)
Özsaraç, Seçkin; Yeşilkaya, Muhammed
2015-05-01
Flares are used as valuable electronic warfare assets for the battle against infrared guided missiles. The trajectory of the flare is one of the most important factors that determine the effectiveness of the counter measure. Reconstruction of the three dimensional (3D) position of a point, which is seen by multiple cameras, is a common problem. Camera placement, camera calibration, corresponding pixel determination in between the images of different cameras and also the triangulation algorithm affect the performance of 3D position estimation. In this paper, we specifically investigate the effects of camera placement on the flare trajectory estimation performance by simulations. Firstly, 3D trajectory of a flare and also the aircraft, which dispenses the flare, are generated with simple motion models. Then, we place two virtual ideal pinhole camera models on different locations. Assuming the cameras are tracking the aircraft perfectly, the view vectors of the cameras are computed. Afterwards, using the view vector of each camera and also the 3D position of the flare, image plane coordinates of the flare on both cameras are computed using the field of view (FOV) values. To increase the fidelity of the simulation, we have used two sources of error. One is used to model the uncertainties in the determination of the camera view vectors, i.e. the orientations of the cameras are measured noisy. Second noise source is used to model the imperfections of the corresponding pixel determination of the flare in between the two cameras. Finally, 3D position of the flare is estimated using the corresponding pixel indices, view vector and also the FOV of the cameras by triangulation. All the processes mentioned so far are repeated for different relative camera placements so that the optimum estimation error performance is found for the given aircraft and are trajectories.
Adaptive estimation of hand movement trajectory in an EEG based brain-computer interface system
NASA Astrophysics Data System (ADS)
Robinson, Neethu; Guan, Cuntai; Vinod, A. P.
2015-12-01
Objective. The various parameters that define a hand movement such as its trajectory, speed, etc, are encoded in distinct brain activities. Decoding this information from neurophysiological recordings is a less explored area of brain-computer interface (BCI) research. Applying non-invasive recordings such as electroencephalography (EEG) for decoding makes the problem more challenging, as the encoding is assumed to be deep within the brain and not easily accessible by scalp recordings. Approach. EEG based BCI systems can be developed to identify the neural features underlying movement parameters that can be further utilized to provide a detailed and well defined control command set to a BCI output device. A real-time continuous control is better suited for practical BCI systems, and can be achieved by continuous adaptive reconstruction of movement trajectory than discrete brain activity classifications. In this work, we adaptively reconstruct/estimate the parameters of two-dimensional hand movement trajectory, namely movement speed and position, from multi-channel EEG recordings. The data for analysis is collected by performing an experiment that involved center-out right-hand movement tasks in four different directions at two different speeds in random order. We estimate movement trajectory using a Kalman filter that models the relation between brain activity and recorded parameters based on a set of defined predictors. We propose a method to define these predictor variables that includes spatial, spectral and temporally localized neural information and to select optimally informative variables. Main results. The proposed method yielded correlation of (0.60 ± 0.07) between recorded and estimated data. Further, incorporating the proposed predictor subset selection, the correlation achieved is (0.57 ± 0.07, p {\\lt }0.004) with significant gain in stability of the system, as well as dramatic reduction in number of predictors (76%) for the savings of computational time. Significance. The proposed system provides a real time movement control system using EEG-BCI with control over movement speed and position. These results are higher and statistically significant compared to existing techniques in EEG based systems and thus promise the applicability of the proposed method for efficient estimation of movement parameters and for continuous motor control.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bakhtiari, M; Schmitt, J; Sarfaraz, M
2015-06-15
Purpose: To establish a minimum number of patients required to obtain statistically accurate Planning Target Volume (PTV) margins for prostate Intensity Modulated Radiation Therapy (IMRT). Methods: A total of 320 prostate patients, consisting of a total number of 9311 daily setups, were analyzed. These patients had gone under IMRT treatments. Daily localization was done using the skin marks and the proper shifts were determined by the CBCT to match the prostate gland. The Van Herk formalism is used to obtain the margins using the systematic and random setup variations. The total patient population was divided into different grouping sizes varyingmore » from 1 group of 320 patients to 64 groups of 5 patients. Each grouping was used to determine the average PTV margin and its associated standard deviation. Results: Analyzing all 320 patients lead to an average Superior-Inferior margin of 1.15 cm. The grouping with 10 patients per group (32 groups) resulted to an average PTV margin between 0.6–1.7 cm with the mean value of 1.09 cm and a standard deviation (STD) of 0.30 cm. As the number of patients in groups increases the mean value of average margin between groups tends to converge to the true average PTV of 1.15 cm and STD decreases. For groups of 20, 64, and 160 patients a Superior-Inferior margin of 1.12, 1.14, and 1.16 cm with STD of 0.22, 0.11, and 0.01 cm were found, respectively. Similar tendency was observed for Left-Right and Anterior-Posterior margins. Conclusion: The estimation of the required margin for PTV strongly depends on the number of patients studied. According to this study at least ∼60 patients are needed to calculate a statistically acceptable PTV margin for a criterion of STD < 0.1 cm. Numbers greater than ∼60 patients do little to increase the accuracy of the PTV margin estimation.« less
NASA Astrophysics Data System (ADS)
O'Shea, Tuathan P.; Garcia, Leo J.; Rosser, Karen E.; Harris, Emma J.; Evans, Philip M.; Bamber, Jeffrey C.
2014-04-01
This study investigates the use of a mechanically-swept 3D ultrasound (3D-US) probe for soft-tissue displacement monitoring during prostate irradiation, with emphasis on quantifying the accuracy relative to CyberKnife® x-ray fiducial tracking. An US phantom, implanted with x-ray fiducial markers was placed on a motion platform and translated in 3D using five real prostate motion traces acquired using the Calypso system. Motion traces were representative of all types of motion as classified by studying Calypso data for 22 patients. The phantom was imaged using a 3D swept linear-array probe (to mimic trans-perineal imaging) and, subsequently, the kV x-ray imaging system on CyberKnife. A 3D cross-correlation block-matching algorithm was used to track speckle in the ultrasound data. Fiducial and US data were each compared with known phantom displacement. Trans-perineal 3D-US imaging could track superior-inferior (SI) and anterior-posterior (AP) motion to ≤0.81 mm root-mean-square error (RMSE) at a 1.7 Hz volume rate. The maximum kV x-ray tracking RMSE was 0.74 mm, however the prostate motion was sampled at a significantly lower imaging rate (mean: 0.04 Hz). Initial elevational (right-left RL) US displacement estimates showed reduced accuracy but could be improved (RMSE <2.0 mm) using a correlation threshold in the ultrasound tracking code to remove erroneous inter-volume displacement estimates. Mechanically-swept 3D-US can track the major components of intra-fraction prostate motion accurately but exhibits some limitations. The largest US RMSE was for elevational (RL) motion. For the AP and SI axes, accuracy was sub-millimetre. It may be feasible to track prostate motion in 2D only. 3D-US also has the potential to improve high tracking accuracy for all motion types. It would be advisable to use US in conjunction with a small (˜2.0 mm) centre-of-mass displacement threshold in which case it would be possible to take full advantage of the accuracy and high imaging rate capability.
NASA Astrophysics Data System (ADS)
Ghafaryasl, Babak; Baart, Robert; de Boer, Johannes F.; Vermeer, Koenraad A.; van Vliet, Lucas J.
2017-02-01
Optical coherence tomography (OCT) yields high-resolution, three-dimensional images of the retina. A better understanding of retinal nerve fiber bundle (RNFB) trajectories in combination with visual field data may be used for future diagnosis and monitoring of glaucoma. However, manual tracing of these bundles is a tedious task. In this work, we present an automatic technique to estimate the orientation of RNFBs from volumetric OCT scans. Our method consists of several steps, starting from automatic segmentation of the RNFL. Then, a stack of en face images around the posterior nerve fiber layer interface was extracted. The image showing the best visibility of RNFB trajectories was selected for further processing. After denoising the selected en face image, a semblance structure-oriented filter was applied to probe the strength of local linear structure in a discrete set of orientations creating an orientation space. Gaussian filtering along the orientation axis in this space is used to find the dominant orientation. Next, a confidence map was created to supplement the estimated orientation. This confidence map was used as pixel weight in normalized convolution to regularize the semblance filter response after which a new orientation estimate can be obtained. Finally, after several iterations an orientation field corresponding to the strongest local orientation was obtained. The RNFB orientations of six macular scans from three subjects were estimated. For all scans, visual inspection shows a good agreement between the estimated orientation fields and the RNFB trajectories in the en face images. Additionally, a good correlation between the orientation fields of two scans of the same subject was observed. Our method was also applied to a larger field of view around the macula. Manual tracing of the RNFB trajectories shows a good agreement with the automatically obtained streamlines obtained by fiber tracking.
NASA Astrophysics Data System (ADS)
Chatzidakis, Stylianos; Liu, Zhengzhi; Hayward, Jason P.; Scaglione, John M.
2018-03-01
This work presents a generalized muon trajectory estimation algorithm to estimate the path of a muon in either uniform or nonuniform media. The use of cosmic ray muons in nuclear nonproliferation and safeguard verification applications has recently gained attention due to the non-intrusive and passive nature of the inspection, penetrating capabilities, as well as recent advances in detectors that measure position and direction of the individual muons before and after traversing the imaged object. However, muon image reconstruction techniques are limited in resolution due to low muon flux and the effects of multiple Coulomb scattering (MCS). Current reconstruction algorithms, e.g., point of closest approach (PoCA) or straight-line path (SLP), rely on overly simple assumptions for muon path estimation through the imaged object. For robust muon tomography, efficient and flexible physics-based algorithms are needed to model the MCS process and accurately estimate the most probable trajectory of a muon as it traverses an object. In the present work, the use of a Bayesian framework and a Gaussian approximation of MCS is explored for estimation of the most likely path of a cosmic ray muon traversing uniform or nonuniform media and undergoing MCS. The algorithm's precision is compared to Monte Carlo simulated muon trajectories. It was found that the algorithm is expected to be able to predict muon tracks to less than 1.5 mm root mean square (RMS) for 0.5 GeV muons and 0.25 mm RMS for 3 GeV muons, a 50% improvement compared to SLP and 15% improvement when compared to PoCA. Further, a 30% increase in useful muon flux was observed relative to PoCA. Muon track prediction improved for higher muon energies or smaller penetration depth where energy loss is not significant. The effect of energy loss due to ionization is investigated, and a linear energy loss relation that is easy to use is proposed.
Chatzidakis, Stylianos; Liu, Zhengzhi; Hayward, Jason P.; ...
2018-03-28
Here, this work presents a generalized muon trajectory estimation (GMTE) algorithm to estimate the path of a muon in either uniform or nonuniform media. The use of cosmic ray muons in nuclear nonproliferation and safeguards verification applications has recently gained attention due to the non-intrusive and passive nature of the inspection, penetrating capabilities, as well as recent advances in detectors that measure position and direction of the individual muons before and after traversing the imaged object. However, muon image reconstruction techniques are limited in resolution due to low muon flux and the effects of multiple Coulomb scattering (MCS). Current reconstructionmore » algorithms, e.g., point of closest approach (PoCA) or straight-line path (SLP), rely on overly simple assumptions for muon path estimation through the imaged object. For robust muon tomography, efficient and flexible physics-based algorithms are needed to model the MCS process and accurately estimate the most probable trajectory of a muon as it traverses an object. In the present work, the use of a Bayesian framework and a Gaussian approximation of MCS are explored for estimation of the most likely path of a cosmic ray muon traversing uniform or nonuniform media and undergoing MCS. The algorithm’s precision is compared to Monte Carlo simulated muon trajectories. It was found that the algorithm is expected to be able to predict muon tracks to less than 1.5 mm RMS for 0.5 GeV muons and 0.25 mm RMS for 3 GeV muons, a 50% improvement compared to SLP and 15% improvement when compared to PoCA. Further, a 30% increase in useful muon flux was observed relative to PoCA. Muon track prediction improved for higher muon energies or smaller penetration depth where energy loss is not significant. Finally, the effect of energy loss due to ionization is investigated, and a linear energy loss relation that is easy to use is proposed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chatzidakis, Stylianos; Liu, Zhengzhi; Hayward, Jason P.
Here, this work presents a generalized muon trajectory estimation (GMTE) algorithm to estimate the path of a muon in either uniform or nonuniform media. The use of cosmic ray muons in nuclear nonproliferation and safeguards verification applications has recently gained attention due to the non-intrusive and passive nature of the inspection, penetrating capabilities, as well as recent advances in detectors that measure position and direction of the individual muons before and after traversing the imaged object. However, muon image reconstruction techniques are limited in resolution due to low muon flux and the effects of multiple Coulomb scattering (MCS). Current reconstructionmore » algorithms, e.g., point of closest approach (PoCA) or straight-line path (SLP), rely on overly simple assumptions for muon path estimation through the imaged object. For robust muon tomography, efficient and flexible physics-based algorithms are needed to model the MCS process and accurately estimate the most probable trajectory of a muon as it traverses an object. In the present work, the use of a Bayesian framework and a Gaussian approximation of MCS are explored for estimation of the most likely path of a cosmic ray muon traversing uniform or nonuniform media and undergoing MCS. The algorithm’s precision is compared to Monte Carlo simulated muon trajectories. It was found that the algorithm is expected to be able to predict muon tracks to less than 1.5 mm RMS for 0.5 GeV muons and 0.25 mm RMS for 3 GeV muons, a 50% improvement compared to SLP and 15% improvement when compared to PoCA. Further, a 30% increase in useful muon flux was observed relative to PoCA. Muon track prediction improved for higher muon energies or smaller penetration depth where energy loss is not significant. Finally, the effect of energy loss due to ionization is investigated, and a linear energy loss relation that is easy to use is proposed.« less
Chen, Jing; Toghi Eshghi, Shadi; Bova, George Steven; Li, Qing Kay; Li, Xingde; Zhang, Hui
2013-12-01
The rapid advancement of high-throughput tools for quantitative measurement of proteins has demonstrated the potential for the identification of proteins associated with cancer. However, the quantitative results on cancer tissue specimens are usually confounded by tissue heterogeneity, e.g. regions with cancer usually have significantly higher epithelium content yet lower stromal content. It is therefore necessary to develop a tool to facilitate the interpretation of the results of protein measurements in tissue specimens. Epithelial cell adhesion molecule (EpCAM) and cathepsin L (CTSL) are two epithelial proteins whose expressions in normal and tumorous prostate tissues were confirmed by measuring staining intensity with immunohistochemical staining (IHC). The expressions of these proteins were measured by ELISA in protein extracts from OCT embedded frozen prostate tissues. To eliminate the influence of tissue heterogeneity on epithelial protein quantification measured by ELISA, a color-based segmentation method was developed in-house for estimation of epithelium content using H&E histology slides from the same prostate tissues and the estimated epithelium percentage was used to normalize the ELISA results. The epithelium contents of the same slides were also estimated by a pathologist and used to normalize the ELISA results. The computer based results were compared with the pathologist's reading. We found that both EpCAM and CTSL levels, measured by ELISA assays itself, were greatly affected by epithelium content in the tissue specimens. Without adjusting for epithelium percentage, both EpCAM and CTSL levels appeared significantly higher in tumor tissues than normal tissues with a p value less than 0.001. However, after normalization by the epithelium percentage, ELISA measurements of both EpCAM and CTSL were in agreement with IHC staining results, showing a significant increase only in EpCAM with no difference in CTSL expression in cancer tissues. These results were obtained with normalization by both the computer estimated and pathologist estimated epithelium percentage. Our results show that estimation of tissue epithelium percentage using our color-based segmentation method correlates well with pathologists' estimation of tissue epithelium percentages. The epithelium contents estimated by color-based segmentation may be useful in immuno-based analysis or clinical proteomic analysis of tumor proteins. The codes used for epithelium estimation as well as the micrographs with estimated epithelium content are available online.
Reliable Change and Outcome Trajectories Across Levels of Care in a Mental Health System for Youth.
Jackson, David S; Keir, Scott S; Sender, Max; Mueller, Charles W
2017-01-01
Knowledge of mental health treatment outcome trajectories across various service types can be valuable for both system- and client-level decision-making. Using longitudinal youth functional impairment scores across 2807 treatment episodes, this study examined outcome trajectories and estimated the number of months required for reliable change across nine major services (or levels of care). Results indicate logarithmic improvement trajectories for a majority of levels of care and significant differences in time until improvement ranging from 4 to 12 months. Findings can guide system-level policies on lengths of treatment and service authorizations and provide expected treatment response data for client-level treatment decisions.
Trajectory-based visual localization in underwater surveying missions.
Burguera, Antoni; Bonin-Font, Francisco; Oliver, Gabriel
2015-01-14
We present a new vision-based localization system applied to an autonomous underwater vehicle (AUV) with limited sensing and computation capabilities. The traditional EKF-SLAM approaches are usually expensive in terms of execution time; the approach presented in this paper strengthens this method by adopting a trajectory-based schema that reduces the computational requirements. The pose of the vehicle is estimated using an extended Kalman filter (EKF), which predicts the vehicle motion by means of a visual odometer and corrects these predictions using the data associations (loop closures) between the current frame and the previous ones. One of the most important steps in this procedure is the image registration method, as it reinforces the data association and, thus, makes it possible to close loops reliably. Since the use of standard EKFs entail linearization errors that can distort the vehicle pose estimations, the approach has also been tested using an iterated Kalman filter (IEKF). Experiments have been conducted using a real underwater vehicle in controlled scenarios and in shallow sea waters, showing an excellent performance with very small errors, both in the vehicle pose and in the overall trajectory estimates.
The trajectory and atmospheric impact of asteroid 2014 AA
NASA Astrophysics Data System (ADS)
Farnocchia, Davide; Chesley, Steven R.; Brown, Peter G.; Chodas, Paul W.
2016-08-01
Near-Earth asteroid 2014 AA entered the Earth's atmosphere on 2014 January 2, only 21 h after being discovered by the Catalina Sky Survey. In this paper we compute the trajectory of 2014 AA by combining the available optical astrometry, seven ground-based observations over 69 min, and the International Monitoring System detection of the atmospheric impact infrasonic airwaves in a least-squares orbit estimation filter. The combination of these two sources of observations results in a tremendous improvement in the orbit uncertainties. The impact time is 3:05 UT with a 1σ uncertainty of 6 min, while the impact location corresponds to a west longitude of 44.2° and a latitude of 13.1° with a 1σ uncertainty of 140 km. The minimum impact energy estimated from the infrasound data and the impact velocity result in an estimated minimum mass of 22.6 t. By propagating the trajectory of 2014 AA backwards we find that the only window for finding precovery observations is for the three days before its discovery.
NASA Technical Reports Server (NTRS)
Lugo, Rafael A.; Tolson, Robert H.; Schoenenberger, Mark
2013-01-01
As part of the Mars Science Laboratory (MSL) trajectory reconstruction effort at NASA Langley Research Center, free-flight aeroballistic experiments of instrumented MSL scale models was conducted at Aberdeen Proving Ground in Maryland. The models carried an inertial measurement unit (IMU) and a flush air data system (FADS) similar to the MSL Entry Atmospheric Data System (MEADS) that provided data types similar to those from the MSL entry. Multiple sources of redundant data were available, including tracking radar and on-board magnetometers. These experimental data enabled the testing and validation of the various tools and methodologies that will be used for MSL trajectory reconstruction. The aerodynamic parameters Mach number, angle of attack, and sideslip angle were estimated using minimum variance with a priori to combine the pressure data and pre-flight computational fluid dynamics (CFD) data. Both linear and non-linear pressure model terms were also estimated for each pressure transducer as a measure of the errors introduced by CFD and transducer calibration. Parameter uncertainties were estimated using a "consider parameters" approach.
Equilibrium-point control hypothesis examined by measured arm stiffness during multijoint movement.
Gomi, H; Kawato
1996-04-05
For the last 20 years, it has been hypothesized that well-coordinated, multijoint movements are executed without complex computation by the brain, with the use of springlike muscle properties and peripheral neural feedback loops. However, it has been technically and conceptually difficult to examine this "equilibrium-point control" hypothesis directly in physiological or behavioral experiments. A high-performance manipulandum was developed and used here to measure human arm stiffness, the magnitude of which during multijoint movement is important for this hypothesis. Here, the equilibrium-point trajectory was estimated from the measured stiffness, the actual trajectory, and the generated torque. Its velocity profile differed from that of the actual trajectory. These results argue against the hypothesis that the brain sends as a motor command only an equilibrium-point trajectory similar to the actual trajectory.
NASA Technical Reports Server (NTRS)
Keppenne, Christian L.; Rienecker, Michele M.; Kovach, Robin M.; Vernieres, Guillaume; Koster, Randal D. (Editor)
2014-01-01
An attractive property of ensemble data assimilation methods is that they provide flow dependent background error covariance estimates which can be used to update fields of observed variables as well as fields of unobserved model variables. Two methods to estimate background error covariances are introduced which share the above property with ensemble data assimilation methods but do not involve the integration of multiple model trajectories. Instead, all the necessary covariance information is obtained from a single model integration. The Space Adaptive Forecast error Estimation (SAFE) algorithm estimates error covariances from the spatial distribution of model variables within a single state vector. The Flow Adaptive error Statistics from a Time series (FAST) method constructs an ensemble sampled from a moving window along a model trajectory. SAFE and FAST are applied to the assimilation of Argo temperature profiles into version 4.1 of the Modular Ocean Model (MOM4.1) coupled to the GEOS-5 atmospheric model and to the CICE sea ice model. The results are validated against unassimilated Argo salinity data. They show that SAFE and FAST are competitive with the ensemble optimal interpolation (EnOI) used by the Global Modeling and Assimilation Office (GMAO) to produce its ocean analysis. Because of their reduced cost, SAFE and FAST hold promise for high-resolution data assimilation applications.
NASA Technical Reports Server (NTRS)
Keppenne, Christian L.; Rienecker, Michele; Kovach, Robin M.; Vernieres, Guillaume
2014-01-01
An attractive property of ensemble data assimilation methods is that they provide flow dependent background error covariance estimates which can be used to update fields of observed variables as well as fields of unobserved model variables. Two methods to estimate background error covariances are introduced which share the above property with ensemble data assimilation methods but do not involve the integration of multiple model trajectories. Instead, all the necessary covariance information is obtained from a single model integration. The Space Adaptive Forecast error Estimation (SAFE) algorithm estimates error covariances from the spatial distribution of model variables within a single state vector. The Flow Adaptive error Statistics from a Time series (FAST) method constructs an ensemble sampled from a moving window along a model trajectory.SAFE and FAST are applied to the assimilation of Argo temperature profiles into version 4.1 of the Modular Ocean Model (MOM4.1) coupled to the GEOS-5 atmospheric model and to the CICE sea ice model. The results are validated against unassimilated Argo salinity data. They show that SAFE and FAST are competitive with the ensemble optimal interpolation (EnOI) used by the Global Modeling and Assimilation Office (GMAO) to produce its ocean analysis. Because of their reduced cost, SAFE and FAST hold promise for high-resolution data assimilation applications.
Murray, Louise; Mason, Joshua; Henry, Ann M; Hoskin, Peter; Siebert, Frank-Andre; Venselaar, Jack; Bownes, Peter
2016-08-01
To estimate the risks of radiation-induced rectal and bladder cancers following low dose rate (LDR) and high dose rate (HDR) brachytherapy as monotherapy for localised prostate cancer and compare to external beam radiotherapy techniques. LDR and HDR brachytherapy monotherapy plans were generated for three prostate CT datasets. Second cancer risks were assessed using Schneider's concept of organ equivalent dose. LDR risks were assessed according to a mechanistic model and a bell-shaped model. HDR risks were assessed according to a bell-shaped model. Relative risks and excess absolute risks were estimated and compared to external beam techniques. Excess absolute risks of second rectal or bladder cancer were low for both LDR (irrespective of the model used for calculation) and HDR techniques. Average excess absolute risks of rectal cancer for LDR brachytherapy according to the mechanistic model were 0.71 per 10,000 person-years (PY) and 0.84 per 10,000 PY respectively, and according to the bell-shaped model, were 0.47 and 0.78 per 10,000 PY respectively. For HDR, the average excess absolute risks for second rectal and bladder cancers were 0.74 and 1.62 per 10,000 PY respectively. The absolute differences between techniques were very low and clinically irrelevant. Compared to external beam prostate radiotherapy techniques, LDR and HDR brachytherapy resulted in the lowest risks of second rectal and bladder cancer. This study shows both LDR and HDR brachytherapy monotherapy result in low estimated risks of radiation-induced rectal and bladder cancer. LDR resulted in lower bladder cancer risks than HDR, and lower or similar risks of rectal cancer. In absolute terms these differences between techniques were very small. Compared to external beam techniques, second rectal and bladder cancer risks were lowest for brachytherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Knipe, Duleeka W; Evans, David M; Kemp, John P.; Eeles, Rosalind; Easton, Douglas F; Kote-Jarai, Zsofia; Al Olama, Ali Amin; Benlloch, Sara; Donovan, Jenny L.; Hamdy, Freddie C.; Neal, David E
2014-01-01
Background Only a minority of the genetic component of prostate cancer (PrCa) risk has been explained. Some observed associations of single nucleotide polymorphisms (SNPs) with PrCa might arise from associations of these SNPs with circulating prostate specific antigen (PSA) because PSA values are used to select controls. Methods We undertook a genome-wide association study (GWAS) of screen detected PrCa (ProtecT 1146 cases and 1804 controls); meta-analysed the results with those from the previously published UK Genetic Prostate Cancer Study (1854 cases and 1437 controls); investigated associations of SNPs with PrCa using either ‘low’ (PSA <0.5ng/ml) or ‘high’ (PSA ≥3ng/ml, biopsy negative) PSA controls; and investigated associations of SNPs with PSA. Results The ProtecT GWAS confirmed previously reported associations of PrCa at 3 loci: 10q11.23, 17q24.3 and 19q13.33. The meta-analysis confirmed associations of PrCa with SNPs near 4 previously identified loci (8q24.21,10q11.23, 17q24.3 and 19q13.33). When comparing PrCa cases with low PSA controls, alleles at genetic markers rs1512268, rs445114, rs10788160, rs11199874, rs17632542, rs266849 and rs2735839 were associated with an increased risk of PrCa, but the effect-estimates were attenuated to the null when using high PSA controls (p for heterogeneity in effect-estimates<0.04). We found a novel inverse association of rs9311171-T with circulating PSA. Conclusions Differences in effect estimates for PrCa observed when comparing low vs. high PSA controls, may be explained by associations of these SNPs with PSA. Impact These findings highlight the need for inferences from genetic studies of PrCa risk to carefully consider the influence of control selection criteria. PMID:24753544
Adrenergic blockers and the risk for common solid cancers: a case-control study.
Numbere, Beade; Fleming, Kate M; Walker, Alex; Card, Timothy R
2017-01-01
Laboratory studies have suggested that adrenergic blockers may inhibit the proliferation and migration of cancer cells, but epidemiological evidence of their effect on cancer incidence has proven inconsistent. We therefore conducted a case-control study using the Clinical Practice Research Datalink to assess the effect of adrenergic blockers on the incidence of prostate, lung, bowel and breast cancers. From among patients aged 18 years or older who contributed at least 2 years of prospectively gathered data between 1 January 1987 and 31 December 2012, we selected incident cases of relevant cancers and controls, frequency matched 10 : 1 by age. Logistic regression was used to adjust effect estimates for age, sex, smoking, alcohol use, and a number of potentially confounding comorbidities and coprescriptions. A total of 18 968 colorectal, 19 082 lung, 21 608 prostate and 29 109 breast cancers were identified. We found no evidence of a protective effect of adrenergic blockade in lung and prostate cancers and found a slightly increased risk for colorectal and breast cancers in users. This was largely explained by the effects of confounding in multivariate analyses, with final odds ratio estimates for lung, colorectal, breast and prostate cancers of 0.99 [95% confidence interval (0.96-1.04)], 1.14 (1.09-1.18), 1.10 (1.06-1.14), and 1.01 (0.98-1.05), respectively, for β-blocker exposure, and final odds ratio estimates for lung, colorectal and breast cancer of 1.03 (0.97-1.09), 1.13 (1.07-1.20), and 1.08 (1.00-1.17), respectively, for α-blocker exposure. We found no evidence to suggest that adrenergic blocker use prevents common cancers. Indeed, we found a slightly increased risk for colorectal and breast cancers, which may reflect residual confounding.
Pizza consumption and the risk of breast, ovarian and prostate cancer.
Gallus, Silvano; Talamini, Renato; Bosetti, Cristina; Negri, Eva; Montella, Maurizio; Franceschi, Silvia; Giacosa, Attilio; La Vecchia, Carlo
2006-02-01
Pizza has been favourably related to the risk of prostate cancer in North America. Scanty information, however, is available on sex hormone-related cancer sites. We therefore studied the role of pizza consumption on the risk of breast, ovarian and prostate cancers using data from three hospital-based case-control studies conducted in Italy between 1991 and 2002. These included 2569 women with breast cancer, 1031 with ovarian cancer, 1294 men with prostate cancer, and a total of 4864 controls. Compared with non-pizza eaters, the multivariate odds ratios for eaters were 0.97 (95% confidence interval (CI) 0.86-1.10) for breast, 1.06 (95% CI 0.89-1.26) for ovarian and 1.04 (95% CI 0.88-1.23) for prostate cancer. Corresponding estimates for regular eaters (i.e. > or =1 portion per week) were 0.92 (95% CI 0.78-1.08), 1.00 (95% CI 0.80-1.25) and 1.12 (95% CI 0.88-1.43), respectively. Our results do not show a relevant role of pizza on the risk of sex hormone-related cancers. The difference with selected studies from North America suggests that dietary and lifestyle correlates of pizza eating vary between different populations and social groups.
A monte carlo study of restricted diffusion: Implications for diffusion MRI of prostate cancer.
Gilani, Nima; Malcolm, Paul; Johnson, Glyn
2017-04-01
Diffusion MRI is used frequently to assess prostate cancer. The prostate consists of cellular tissue surrounding fluid filled ducts. Here, the diffusion properties of the ductal fluid alone were studied. Monte Carlo simulations were used to investigate ductal residence times to determine whether ducts can be regarded as forming a separate compartment and whether ductal radius could determine the Apparent Diffusion Coefficient (ADC) of the ductal fluid. Random walks were simulated in cavities. Average residence times were estimated for permeable cavities. Signal reductions resulting from application of a Stejskal-Tanner pulse sequence were calculated in impermeable cavities. Simulations were repeated for cavities of different radii and different diffusion times. Residence times are at least comparable with diffusion times even in relatively high grade tumors. ADCs asymptotically approach theoretical limiting values. At large radii and short diffusion times, ADCs are similar to free diffusion. At small radii and long diffusion times, ADCs are reduced toward zero, and kurtosis approaches a value of -1.2. Restricted diffusion in cavities of similar sizes to prostate ducts may reduce ductal ADCs. This may contribute to reductions in total ADC seen in prostate cancer. Magn Reson Med 77:1671-1677, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
Statin and NSAID Use and Prostate Cancer Risk
Coogan, Patricia F.; Kelly, Judith Parsells; Strom, Brian L.; Rosenberg, Lynn
2010-01-01
Purpose Some studies have reported reduced risks of advanced, but not early, prostate cancer among statin users, and one study found a reduced risk only among statin users who had also used nonsteroidal anti-inflammatory drugs (NSAIDs). We have previously reported no association between statin use and prostate cancer in our hospital-based Case Control Surveillance Study. The purpose of the present analyses was to update the findings by cancer stage and to evaluate the joint use of statins and NSAIDs. Methods Cases were 1367 men with prostate cancer and controls were 2007 men with diagnoses unrelated to statin or NSAID use. We used multivariable logistic regression analyses to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for statin use compared with no use, and joint use of statin and NSAIDs compared with use of neither. Results The odds ratio among regular statin users was 1.1 (95% CI 0.9–1.5), and odds ratios were similar among early and late stage cancers. The odds ratio among joint statin and NSAID users was 1.1 (95% CI 0.7–1.6). Conclusion The present results do not support a protective effect of statin use, or statin and NSAID use, on the risk of advanced prostate cancer. PMID:20582910
2D trajectory estimation during free walking using a tiptoe-mounted inertial sensor.
Sagawa, Koichi; Ohkubo, Kensuke
2015-07-16
An estimation method for a two-dimensional walking trajectory during free walking, such as forward walking, side stepping and backward walking, was investigated using a tiptoe-mounted inertial sensor. The horizontal trajectory of the toe-tip is obtained by double integration of toe-tip acceleration during the moving phase in which the sensor is rotated before foot-off or after foot-contact, in addition to the swing phase. Special functions that determine the optimum moving phase as the integral duration in every one step are developed statistically using the gait cycle and the resultant angular velocity of dorsi/planter flexion, pronation/supination and inversion/eversion so that the difference between the estimated trajectory and actual one gives a minimum value during free walking with several cadences. To develop the functions, twenty healthy volunteers participated in free walking experiments in which subjects performed forward walking, side stepping to the right, side stepping to the left, and backward walking at 39 m down a straight corridor with several predetermined cadences. To confirm the effect of the developed functions, five healthy subjects participated in the free walking experiment in which each subject performed free walking with different velocities of normal, fast, and slow based on their own assessment in a square course with 7 m side. The experimentally obtained results of free walking with a combination of forward walking, backward walking, and side stepping indicate that the proposed method produces walking trajectory with high precision compared with the constant threshold method which determines swing phase using the size of the angular velocity. Copyright © 2015 Elsevier Ltd. All rights reserved.
Prostate cancer risk prediction based on complete prostate cancer family history.
Albright, Frederick; Stephenson, Robert A; Agarwal, Neeraj; Teerlink, Craig C; Lowrance, William T; Farnham, James M; Albright, Lisa A Cannon
2015-03-01
Prostate cancer (PC) relative risks (RRs) are typically estimated based on status of close relatives or presence of any affected relatives. This study provides RR estimates using extensive and specific PC family history. A retrospective population-based study was undertaken to estimate RRs for PC based on complete family history of PC. A total of 635,443 males, all with ancestral genealogy data, were analyzed. RRs for PC were determined based upon PC rates estimated from males with no PC family history (without PC in first, second, or third degree relatives). RRs were determined for a variety of constellations, for example, number of first through third degree relatives; named (grandfather, father, uncle, cousins, brothers); maternal, paternal relationships, and age of onset. In the 635,443 males analyzed, 18,105 had PC. First-degree RRs ranged from 2.46 (=1 first-degree relative affected, CI = 2.39-2.53) to 7.65 (=4 first-degree relatives affected, CI = 6.28-9.23). Second-degree RRs for probands with 0 affected first-degree relatives ranged from 1.51 (≥1 second-degree relative affected, CI = 1.47-1.56) to 3.09 (≥5 second-degree relatives affected, CI = 2.32-4.03). Third-degree RRs with 0 affected first- and 0 affected second-degree relatives ranged from 1.15 (≥1 affected third-degree relative, CI = 1.12-1.19) to 1.50 (≥5 affected third-degree relatives, CI = 1.35-1.66). RRs based on age at diagnosis were higher for earlier age at diagnoses; for example, RR = 5.54 for ≥1 first-degree relative diagnosed before age 50 years (CI = 1.12-1.19) and RR = 1.78 for >1 second-degree relative diagnosed before age 50 years, CI = 1.33, 2.33. RRs for equivalent maternal versus paternal family history were not significantly different. A more complete PC family history using close and distant relatives and age at diagnosis results in a wider range of estimates of individual RR that are potentially more accurate than RRs estimated from summary family history. The presence of PC in second- and even third-degree relatives contributes significantly to risk. Maternal family history is just as significant as paternal family history. PC RRs based on a proband's complete constellation of affected relatives will allow patients and care providers to make more informed screening, monitoring, and treatment decisions. © 2014 The Authors. The Prostate Published by Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Mosquera Lopez, Clara; Agaian, Sos
2013-02-01
Prostate cancer detection and staging is an important step towards patient treatment selection. Advancements in digital pathology allow the application of new quantitative image analysis algorithms for computer-assisted diagnosis (CAD) on digitized histopathology images. In this paper, we introduce a new set of features to automatically grade pathological images using the well-known Gleason grading system. The goal of this study is to classify biopsy images belonging to Gleason patterns 3, 4, and 5 by using a combination of wavelet and fractal features. For image classification we use pairwise coupling Support Vector Machine (SVM) classifiers. The accuracy of the system, which is close to 97%, is estimated through three different cross-validation schemes. The proposed system offers the potential for automating classification of histological images and supporting prostate cancer diagnosis.
Hypersonic entry vehicle state estimation using nonlinearity-based adaptive cubature Kalman filters
NASA Astrophysics Data System (ADS)
Sun, Tao; Xin, Ming
2017-05-01
Guidance, navigation, and control of a hypersonic vehicle landing on the Mars rely on precise state feedback information, which is obtained from state estimation. The high uncertainty and nonlinearity of the entry dynamics make the estimation a very challenging problem. In this paper, a new adaptive cubature Kalman filter is proposed for state trajectory estimation of a hypersonic entry vehicle. This new adaptive estimation strategy is based on the measure of nonlinearity of the stochastic system. According to the severity of nonlinearity along the trajectory, the high degree cubature rule or the conventional third degree cubature rule is adaptively used in the cubature Kalman filter. This strategy has the benefit of attaining higher estimation accuracy only when necessary without causing excessive computation load. The simulation results demonstrate that the proposed adaptive filter exhibits better performance than the conventional third-degree cubature Kalman filter while maintaining the same performance as the uniform high degree cubature Kalman filter but with lower computation complexity.
BASU, ANIRBAN
2014-01-01
SUMMARY This paper builds on the methods of local instrumental variables developed by Heckman and Vytlacil (1999, 2001, 2005) to estimate person-centered treatment (PeT) effects that are conditioned on the person’s observed characteristics and averaged over the potential conditional distribution of unobserved characteristics that lead them to their observed treatment choices. PeT effects are more individualized than conditional treatment effects from a randomized setting with the same observed characteristics. PeT effects can be easily aggregated to construct any of the mean treatment effect parameters and, more importantly, are well suited to comprehend individual-level treatment effect heterogeneity. The paper presents the theory behind PeT effects, and applies it to study the variation in individual-level comparative effects of prostate cancer treatments on overall survival and costs. PMID:25620844
Bonmati, Ester; Hu, Yipeng; Villarini, Barbara; Rodell, Rachael; Martin, Paul; Han, Lianghao; Donaldson, Ian; Ahmed, Hashim U; Moore, Caroline M; Emberton, Mark; Barratt, Dean C
2018-04-01
Image-guided systems that fuse magnetic resonance imaging (MRI) with three-dimensional (3D) ultrasound (US) images for performing targeted prostate needle biopsy and minimally invasive treatments for prostate cancer are of increasing clinical interest. To date, a wide range of different accuracy estimation procedures and error metrics have been reported, which makes comparing the performance of different systems difficult. A set of nine measures are presented to assess the accuracy of MRI-US image registration, needle positioning, needle guidance, and overall system error, with the aim of providing a methodology for estimating the accuracy of instrument placement using a MR/US-guided transperineal approach. Using the SmartTarget fusion system, an MRI-US image alignment error was determined to be 2.0 ± 1.0 mm (mean ± SD), and an overall system instrument targeting error of 3.0 ± 1.2 mm. Three needle deployments for each target phantom lesion was found to result in a 100% lesion hit rate and a median predicted cancer core length of 5.2 mm. The application of a comprehensive, unbiased validation assessment for MR/US guided systems can provide useful information on system performance for quality assurance and system comparison. Furthermore, such an analysis can be helpful in identifying relationships between these errors, providing insight into the technical behavior of these systems. © 2018 American Association of Physicists in Medicine.
Solution to Projectile Motion with Quadratic Drag and Graphing the Trajectory in Spreadsheets
ERIC Educational Resources Information Center
Benacka, Jan
2010-01-01
This note gives the analytical solution to projectile motion with quadratic drag by decomposing the velocity vector to "x," "y" coordinate directions. The solution is given by definite integrals. First, the impact angle is estimated from above, then the projectile coordinates are computed, and the trajectory is graphed at various launch angles and…
ERIC Educational Resources Information Center
Lee, Jaekyung
2012-01-01
This study addresses missing links in "college for all" debates by investigating gaps between actual and desirable math achievement trajectories for students' college readiness. Linking multiple national data sets across P-16 education levels, the study estimates college readiness benchmarks separately for two-year and four-year college…
ERIC Educational Resources Information Center
Whittaker, Tiffany A.; Khojasteh, Jam
2017-01-01
Latent growth modeling (LGM) is a popular and flexible technique that may be used when data are collected across several different measurement occasions. Modeling the appropriate growth trajectory has important implications with respect to the accurate interpretation of parameter estimates of interest in a latent growth model that may impact…
ERIC Educational Resources Information Center
Lee, Chung Gun; Seo, Dong-Chul; Torabi, Mohammad R.; Lohrmann, David K.; Song, Tae Min
2018-01-01
Background: We examined the longitudinal trajectory of substance use (binge drinking, marijuana use, and cocaine use) in relation to self-esteem from adolescence to young adulthood. Methods: Generalized estimating equation models were fit using SAS to investigate changes in the relation between self-esteem and each substance use (binge drinking,…
Human observers are biased in judging the angular approach of a projectile.
Welchman, Andrew E; Tuck, Val L; Harris, Julie M
2004-01-01
How do we decide whether an object approaching us will hit us? The optic array provides information sufficient for us to determine the approaching trajectory of a projectile. However, when using binocular information, observers report that trajectories near the mid-sagittal plane are wider than they actually are. Here we extend this work to consider stimuli containing additional depth cues. We measure observers' estimates of trajectory direction first for computer rendered, stereoscopically presented, rich-cue objects, and then for real objects moving in the world. We find that, under both rich cue conditions and with real moving objects, observers show positive bias, overestimating the angle of approach when movement is near the mid-sagittal plane. The findings question whether the visual system, using both binocular and monocular cues to depth, can make explicit estimates of the 3-D location and movement of objects in depth.
Rathmann, Wolfgang; Kostev, Karel
2017-04-01
Experimental and animal studies have supported the hypothesis that dipeptidyl peptidase-4 inhibitors (DPP-4i) may accelerate tumor metastasis. The aim was to analyze the relationships between DPP-4i therapy with risk of metastases in type 2 diabetes patients with breast, prostate and digestive organ cancers. Type 2 diabetes patients with first diagnoses of breast, prostate or digestive organ cancer were selected in general and internal medicine practices (Disease Analyzer Germany: 01/2008-12/2014). Propensity score matching between DPP-4i users and non-users was carried out for age, sex, diabetes duration, and metformin use. Time-dependent Cox regression models were used to estimate hazard ratios (HR) for metastases further adjusting for HbA1c, body mass index, comorbidity and co-therapy with glucose-lowering drugs (3-4years follow-up). 668 patients with newly diagnosed breast cancer, 906 with prostate cancer and 908 with digestive organ cancer were analyzed. In Cox regression, use of DPP-4i was not associated with an increased risk of metastases in patients with breast (adjusted HR, 95%CI: 1.00, 0.49-2.02), prostate (0.98, 0.54-1.77) or digestive organ cancers (0.97, 0.57-1.66). This first observational study in patients with type 2 diabetes and breast, prostate or digestive organ cancer found no increased risk of metastases in DPP-4i users. Copyright © 2017 Elsevier Inc. All rights reserved.
Shin, Sangjin; Kim, Youn Hee; Hwang, Jin Sub; Lee, Yoon Jae; Lee, Sang Moo; Ahn, Jeonghoon
2014-01-01
Prostate cancer is rapidly increasing in Korea and professional societies have requested adding prostate specific antigen (PSA) testing to the National Cancer Screening Program (NCSP), but this started a controversy in Korea and neutral evidence on this issue is required more than ever. The purpose of this study was to provide economic evidence to the decision makers of the NCSP. A cost-utility analysis was performed on the adoption of PSA screening program among men aged 50-74-years in Korea from the healthcare system perspective. Several data sources were used for the cost-utility analysis, including general health screening data, the Korea Central Cancer Registry, national insurance claims data, and cause of mortality from the National Statistical Office. To solicit the utility index of prostate cancer, a face-to-face interview for typical men aged 40 to 69 was conducted using a Time-Trade Off method. As a result, the increase of effectiveness was estimated to be very low, when adopting PSA screening, and the incremental cost effectiveness ratio (ICER) was analyzed as about 94 million KRW. Sensitivity analyses were performed on the incidence rate, screening rate, cancer stage distribution, utility index, and treatment costs but the results were consistent with the base analysis. Under Korean circumstances with a relatively low incidence rate of prostate cancer, PSA screening is not cost-effective. Therefore, we conclude that adopting national prostate cancer screening would not be beneficial until further evidence is provided in the future.
Major, Jacqueline M.; Oliver, M. Norman; Doubeni, Chyke A.; Hollenbeck, Albert R.; Graubard, Barry I.; Sinha, Rashmi
2012-01-01
Objectives The purpose of this study was to separately examine the impact of neighborhood socioeconomic deprivation and availability of healthcare resources on prostate cancer risk among African-American and Caucasian men. Methods In the large, prospective NIH-AARP Diet and Health Study, we analyzed baseline (1995–1996) data from adult men, ages 50–71 years. Incident prostate cancer cases (n=22,523; 1,089 among African Americans) were identified through December 2006. Life-style and health risk information was ascertained by questionnaires administered at baseline. Area-level socioeconomic indicators were ascertained by linkage to the US Census and the Area Resource File. Multilevel Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results A differential effect among African Americans and Caucasians was observed for neighborhood deprivation (P-interaction = 0.04), percent uninsured (P-interaction = 0.02), and urologist density (P-interaction = 0.01). Compared to men living in counties with the highest density of urologists, those with fewer had a substantially increased risk of developing advanced prostate cancer (HR=2.68, 95% CI=1.31, 5.47) among African-American. Conclusions Certain socioeconomic indicators were associated with an increased risk of prostate cancer among African-American men compared to Caucasians. Minimizing differences in health care availability may be a potentially important pathway to minimizing disparities in prostate cancer risk. PMID:22674292
Teng, Jingfei; Zhang, Dongxu; Li, Yao; Yin, Lei; Wang, Kai; Cui, Xingang; Xu, Danfeng
2013-02-01
To assess the overall efficacy and safety of photoselective vaporization of the prostate (PVP) vs transurethral resection of the prostate (TURP) for treating patients with lower urinary tract symptoms (LUTS) secondary to benign prostate hyperplasia (BPH). A systematic search of the electronic databases, including MEDLINE, Embase, Web of Science and The Cochrane Library, as well as manual bibliography searches were performed. The pooled estimates of maximum flow rate (Q(max)), postvoid residual (PVR), quality of life (QoL), International Prostate Symptom Score (IPSS), operation duration, blood loss, catheterization time, hospital stay, capsule perforation, transfusion, transurethral resection (TUR) syndrome, urethral stricture and reintervention were calculated. At the 3-month follow-up, there was no significant difference in Q(max), PVR, QoL and IPSS between the TURP and PVP groups. At the 6-month follow-up, the pooled QoL favoured TURP, but there was no significant difference in the other variables between the two groups. PVP was associated with less blood loss, transfusion, capsular perforation, TUR syndrome, shorter catheterization time and hospital stay, but longer operation duration and higher reintervention rate. The efficacy of PVP was similar to that of TURP in relation to Q(max), PVR, QoL and IPSS, and it offered several advantages over TURP. As a promising minimal invasive technique, PVP could be used as an alternative surgical procedure for treating BPH. © 2012 BJU International.
Fast approximate delivery of fluence maps for IMRT and VMAT
NASA Astrophysics Data System (ADS)
Balvert, Marleen; Craft, David
2017-02-01
In this article we provide a method to generate the trade-off between delivery time and fluence map matching quality for dynamically delivered fluence maps. At the heart of our method lies a mathematical programming model that, for a given duration of delivery, optimizes leaf trajectories and dose rates such that the desired fluence map is reproduced as well as possible. We begin with the single fluence map case and then generalize the model and the solution technique to the delivery of sequential fluence maps. The resulting large-scale, non-convex optimization problem was solved using a heuristic approach. We test our method using a prostate case and a head and neck case, and present the resulting trade-off curves. Analysis of the leaf trajectories reveals that short time plans have larger leaf openings in general than longer delivery time plans. Our method allows one to explore the continuum of possibilities between coarse, large segment plans characteristic of direct aperture approaches and narrow field plans produced by sliding window approaches. Exposing this trade-off will allow for an informed choice between plan quality and solution time. Further research is required to speed up the optimization process to make this method clinically implementable.
NASA Astrophysics Data System (ADS)
Liu, Y.; Weisberg, R. H.
2017-12-01
The Lagrangian separation distance between the endpoints of simulated and observed drifter trajectories is often used to assess the performance of numerical particle trajectory models. However, the separation distance fails to indicate relative model performance in weak and strong current regions, such as a continental shelf and its adjacent deep ocean. A skill score is proposed based on the cumulative Lagrangian separation distances normalized by the associated cumulative trajectory lengths. The new metrics correctly indicates the relative performance of the Global HYCOM in simulating the strong currents of the Gulf of Mexico Loop Current and the weaker currents of the West Florida Shelf in the eastern Gulf of Mexico. In contrast, the Lagrangian separation distance alone gives a misleading result. Also, the observed drifter position series can be used to reinitialize the trajectory model and evaluate its performance along the observed trajectory, not just at the drifter end position. The proposed dimensionless skill score is particularly useful when the number of drifter trajectories is limited and neither a conventional Eulerian-based velocity nor a Lagrangian-based probability density function may be estimated.
Glucose trajectories in cystic fibrosis and their association with pulmonary function.
Reynaud, Quitterie; Rabilloud, Muriel; Roche, Sylvain; Poupon-Bourdy, Stéphanie; Iwaz, Jean; Nove-Josserand, Raphaële; Blond, Emilie; Laville, Martine; Llerena, Cathy; Quetant, Sébastien; Reix, Philippe; Touzet, Sandrine; Durieu, Isabelle
2018-05-01
The prevalence of cystic fibrosis-related diabetes is increasing. This condition is potentially responsible for respiratory decline. At inclusion, then yearly (over three years), 111 children and 117 adults with cystic fibrosis had oral glucose tolerance and insulin tests at one (G1) and 2h (G2). KmL analysis identified homogeneous G1 and G2 glucose trajectories. A linear mixed model quantified the relationships between trajectories and FEV1 changes. In children, there were three G1 and four G2 trajectories and FEV1 decrease was not significantly different between G1 or G2 trajectories. In adults, two G1 and four G2 trajectories were identified and FEV1 change was estimated at -0.85/year (95% CI: [-1.54; -0.17], p=0.01) whatever the G1 trajectory and found significantly faster in the high and increasing G2 trajectory (-2.1/year, [-3.9; -0.2], p=0.03). In case of persistent G2 abnormality, physicians should be alert for clinical deterioration and intensify patient surveillance. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.
Lobo, Jennifer M; Trifiletti, Daniel M; Sturz, Vanessa N; Dicker, Adam P; Buerki, Christine; Davicioni, Elai; Cooperberg, Matthew R; Karnes, R Jeffrey; Jenkins, Robert B; Den, Robert B; Showalter, Timothy N
2017-06-01
Controversy exists regarding the effectiveness of early adjuvant versus salvage radiation therapy after prostatectomy for prostate cancer. Estimates of prostate cancer progression from the Decipher genomic classifier (GC) could guide informed decision-making and improve the outcomes for patients. We developed a Markov model to compare the costs and quality-adjusted life years (QALYs) associated with GC-based treatment decisions regarding adjuvant therapy after prostatectomy with those of 2 control strategies: usual care (determined from patterns of care studies) and the alternative of 100% adjuvant radiation therapy. Using the bootstrapping method of sampling with replacement, the cases of 10,000 patients were simulated during a 10-year time horizon, with each subject having individual estimates for cancer progression (according to GC findings) and noncancer mortality (according to age). GC-based care was more effective and less costly than 100% adjuvant radiation therapy and resulted in cost savings up to an assay cost of $11,402. Compared with usual care, GC-based care resulted in more QALYs. Assuming a $4000 assay cost, the incremental cost-effectiveness ratio was $90,833 per QALY, assuming a 7% usage rate of adjuvant radiation therapy. GC-based care was also associated with a 16% reduction in the percentage of patients with distant metastasis at 5 years compared with usual care. The Decipher GC could be a cost-effective approach for genomics-driven cancer treatment decisions after prostatectomy, with improvements in estimated clinical outcomes compared with usual care. The individualized decision analytic framework applied in the present study offers a flexible approach to estimate the potential utility of genomic assays for personalized cancer medicine. Copyright © 2016 Elsevier Inc. All rights reserved.
Personal Genomic Testing for Cancer Risk: Results From the Impact of Personal Genomics Study.
Gray, Stacy W; Gollust, Sarah E; Carere, Deanna Alexis; Chen, Clara A; Cronin, Angel; Kalia, Sarah S; Rana, Huma Q; Ruffin, Mack T; Wang, Catharine; Roberts, J Scott; Green, Robert C
2017-02-20
Purpose Significant concerns exist regarding the potential for unwarranted behavior changes and the overuse of health care resources in response to direct-to-consumer personal genomic testing (PGT). However, little is known about customers' behaviors after PGT. Methods Longitudinal surveys were given to new customers of 23andMe (Mountain View, CA) and Pathway Genomics (San Diego, CA). Survey data were linked to individual-level PGT results through a secure data transfer process. Results Of the 1,042 customers who completed baseline and 6-month surveys (response rate, 71.2%), 762 had complete cancer-related data and were analyzed. Most customers reported that learning about their genetic risk of cancers was a motivation for testing (colorectal, 88%; prostate, 95%; breast, 94%). No customers tested positive for pathogenic mutations in highly penetrant cancer susceptibility genes. A minority of individuals received elevated single nucleotide polymorphism-based PGT cancer risk estimates (colorectal, 24%; prostate, 24%; breast, 12%). At 6 months, customers who received elevated PGT cancer risk estimates were not significantly more likely to change their diet, exercise, or advanced planning behaviors or engage in cancer screening, compared with individuals at average or reduced risk. Men who received elevated PGT prostate cancer risk estimates changed their vitamin and supplement use more than those at average or reduced risk (22% v 7.6%, respectively; adjusted odds ratio, 3.41; 95% CI, 1.44 to 8.18). Predictors of 6-month behavior include baseline behavior (exercise, vitamin or supplement use, and screening), worse health status (diet and vitamin or supplement use), and older age (advanced planning, screening). Conclusion Most adults receiving elevated direct-to-consumer PGT single nucleotide polymorphism-based cancer risk estimates did not significantly change their diet, exercise, advanced care planning, or cancer screening behaviors.
Personal Genomic Testing for Cancer Risk: Results From the Impact of Personal Genomics Study
Gollust, Sarah E.; Carere, Deanna Alexis; Chen, Clara A.; Cronin, Angel; Kalia, Sarah S.; Rana, Huma Q.; Ruffin, Mack T.; Wang, Catharine; Roberts, J. Scott; Green, Robert C.
2017-01-01
Purpose Significant concerns exist regarding the potential for unwarranted behavior changes and the overuse of health care resources in response to direct-to-consumer personal genomic testing (PGT). However, little is known about customers’ behaviors after PGT. Methods Longitudinal surveys were given to new customers of 23andMe (Mountain View, CA) and Pathway Genomics (San Diego, CA). Survey data were linked to individual-level PGT results through a secure data transfer process. Results Of the 1,042 customers who completed baseline and 6-month surveys (response rate, 71.2%), 762 had complete cancer-related data and were analyzed. Most customers reported that learning about their genetic risk of cancers was a motivation for testing (colorectal, 88%; prostate, 95%; breast, 94%). No customers tested positive for pathogenic mutations in highly penetrant cancer susceptibility genes. A minority of individuals received elevated single nucleotide polymorphism-based PGT cancer risk estimates (colorectal, 24%; prostate, 24%; breast, 12%). At 6 months, customers who received elevated PGT cancer risk estimates were not significantly more likely to change their diet, exercise, or advanced planning behaviors or engage in cancer screening, compared with individuals at average or reduced risk. Men who received elevated PGT prostate cancer risk estimates changed their vitamin and supplement use more than those at average or reduced risk (22% v 7.6%, respectively; adjusted odds ratio, 3.41; 95% CI, 1.44 to 8.18). Predictors of 6-month behavior include baseline behavior (exercise, vitamin or supplement use, and screening), worse health status (diet and vitamin or supplement use), and older age (advanced planning, screening). Conclusion Most adults receiving elevated direct-to-consumer PGT single nucleotide polymorphism-based cancer risk estimates did not significantly change their diet, exercise, advanced care planning, or cancer screening behaviors. PMID:27937091
Development of a Mars Airplane Entry, Descent, and Flight Trajectory
NASA Technical Reports Server (NTRS)
Murray, James E.; Tartabini, Paul V.
2001-01-01
An entry, descent, and flight (EDF) trajectory profile for a Mars airplane mission is defined as consisting of the following elements: ballistic entry of an aeroshell; supersonic deployment of a decelerator parachute; subsonic release of a heat shield; release, unfolding, and orientation of an airplane to flight attitude; and execution of a pull up maneuver to achieve trimmed, horizontal flight. Using the Program to Optimize Simulated Trajectories (POST) a trajectory optimization problem was formulated. Model data representative of a specific Mars airplane configuration, current models of the Mars surface topography and atmosphere, and current estimates of the interplanetary trajectory, were incorporated into the analysis. The goal is to develop an EDF trajectory to maximize the surface-relative altitude of the airplane at the end of a pull up maneuver, while subject to the mission design constraints. The trajectory performance was evaluated for three potential mission sites and was found to be site-sensitive. The trajectory performance, examined for sensitivity to a number of design and constraint variables, was found to be most sensitive to airplane mass, aerodynamic performance characteristics, and the pull up Mach constraint. Based on the results of this sensitivity study, an airplane-drag optimized trajectory was developed that showed a significant performance improvement.
Weaver, Kathryn E.; Forsythe, Laura P.; Reeve, Bryce B.; Alfano, Catherine M.; Rodriguez, Juan L.; Sabatino, Susan A.; Hawkins, Nikki A.; Rowland, Julia H.
2012-01-01
Background Despite extensive data on health-related quality of life (HRQOL) among cancer survivors, we do not yet have an estimate of the percent of survivors with poor mental and physical HRQOL compared to population norms. HRQOL population means for adult-onset cancer survivors of all ages and across the survivorship trajectory also have not been published. Methods Survivors (n=1,822) and adults with no cancer history (n=24,804) were identified from the 2010 National Health Interview Survey. The PROMIS® Global Health Scale was used to assess HRQOL. Poor HRQOL was defined as one standard deviation or more below the PROMIS population norm. Results Poor physical and mental HRQOL were reported by 24.5% and 10.1% of survivors, respectively, compared to 10.2% and 5.9% of adults without cancer (both p<.0001). This represents a population of approximately 3.3 million and 1.4 million US survivors with poor physical and mental HRQOL. Adjusted mean mental and physical HRQOL scores were similar for breast, prostate, and melanoma survivors compared to adults without cancer. Survivors of cervical, colorectal, hematologic, short-survival, and other cancers had worse physical HRQOL; cervical and short-survival cancer survivors reported worse mental HRQOL. Conclusion These data elucidate the burden of cancer diagnosis and treatment among US survivors and can be used to monitor the impact of national efforts to improve survivorship care and outcomes. Impact We present novel data on the number of US survivors with poor HRQOL. Interventions for high-risk groups that can be easily implemented are needed to improve survivor health at a population level. PMID:23112268