Definition of the rectum and level of the peritoneal reflection - still a matter of debate?

PubMed

Kenig, Jakub; Richter, Piotr

2013-09-01

Pathological lesions of the rectum are common and their management requires detailed knowledge of pelvic anatomy. There has been considerable debate as to the definition of the rectum and the variability of the level of the peritoneal reflection. The lack of a clear consensus was proven in the research by McCullen et al. regarding the current pattern of practice for the investigation of primary rectal cancer by general surgeons. To carry out bibliographic research on the definition of the rectum and level of the peritoneal reflection. A web-based published literature search of PubMed, Ovid Medline, Science Direct and Springer was made. The paper presents the current definitions of proximal and distal margin of the rectum and level of peritoneal reflection based not only on the results of tests on cadavers but also on living humans. The results of tests on living humans allow more accurate qualification of patients for local excision, which is particularly important for patients with colorectal cancer.

Spatial organization and coordination of slow waves in the mouse anorectum

PubMed Central

Hall, K A; Ward, S M; Cobine, C A; Keef, K D

2014-01-01

The internal anal sphincter (IAS) develops tone and is important for maintaining a high anal pressure while tone in the rectum is less. The mechanisms responsible for tone generation in the IAS are still uncertain. The present study addressed this question by comparing the electrical properties and morphology of the mouse IAS and distal rectum. The amplitude of tone and the frequency of phasic contractions was greater in the IAS than in rectum while membrane potential (Em) was less negative in the IAS than in rectum. Slow waves (SWs) were of greatest amplitude and frequency at the distal end of the IAS, declining in the oral direction. Dual microelectrode recordings revealed that SWs were coordinated over a much greater distance in the circumferential direction than in the oral direction. The circular muscle layer of the IAS was divided into five to eight ‘minibundles’ separated by connective tissue septa whereas few septa were present in the rectum. The limited coordination of SWs in the oral direction suggests that the activity in adjacent minibundles is not coordinated. Intramuscular interstitial cells of Cajal and platelet-derived growth factor receptor alpha-positive cells were present in each minibundle suggesting a role for one or both of these cells in SW generation. In summary, three important properties distinguish the IAS from the distal rectum: (1) a more depolarized Em; (2) larger and higher frequency SWs; and (3) the multiunit configuration of the muscle. All of these characteristics may contribute to greater tone generation in the IAS than in the distal rectum. PMID:24951622

Clinical implementation of a knowledge based planning tool for prostate VMAT.

PubMed

Powis, Richard; Bird, Andrew; Brennan, Matthew; Hinks, Susan; Newman, Hannah; Reed, Katie; Sage, John; Webster, Gareth

2017-05-08

A knowledge based planning tool has been developed and implemented for prostate VMAT radiotherapy plans providing a target average rectum dose value based on previously achievable values for similar rectum/PTV overlap. The purpose of this planning tool is to highlight sub-optimal clinical plans and to improve plan quality and consistency. A historical cohort of 97 VMAT prostate plans was interrogated using a RayStation script and used to develop a local model for predicting optimum average rectum dose based on individual anatomy. A preliminary validation study was performed whereby historical plans identified as "optimal" and "sub-optimal" by the local model were replanned in a blinded study by four experienced planners and compared to the original clinical plan to assess whether any improvement in rectum dose was observed. The predictive model was then incorporated into a RayStation script and used as part of the clinical planning process. Planners were asked to use the script during planning to provide a patient specific prediction for optimum average rectum dose and to optimise the plan accordingly. Plans identified as "sub-optimal" in the validation study observed a statistically significant improvement in average rectum dose compared to the clinical plan when replanned whereas plans that were identified as "optimal" observed no improvement when replanned. This provided confidence that the local model can identify plans that were suboptimal in terms of rectal sparing. Clinical implementation of the knowledge based planning tool reduced the population-averaged mean rectum dose by 5.6Gy. There was a small but statistically significant increase in total MU and femoral head dose and a reduction in conformity index. These did not affect the clinical acceptability of the plans and no significant changes to other plan quality metrics were observed. The knowledge-based planning tool has enabled substantial reductions in population-averaged mean rectum dose for prostate VMAT patients. This suggests plans are improved when planners receive quantitative feedback on plan quality against historical data.

Perceptions of phantom rectum syndrome and health-related quality of life in patients following abdominoperineal resection for rectal cancer.

PubMed

Fingren, Jeanette; Lindholm, Elisabet; Carlsson, Eva

2013-01-01

The aim of the study was to investigate how patients described their perceptions of phantom rectum syndrome after abdominoperineal resection and ostomy creation, and its influence on daily living and health-related quality of life. A further aim was to find out strategies patients use to alleviate phantom rectum syndrome sensations. Twenty-five patients who underwent abdominoperineal resection and a colostomy (18 men and 7 women; median age 5 63 years; range, 40-78 years) at Sahlgrenska University Hospital, Göteborg, Sweden, participated in the study. At follow-up 8 months postsurgery, a WOC nurse interviewed patients with a structured questionnaire about the experience of nonpainful and painful sensations in the perineal area. Health-related quality of life was evaluated using a general cancer-specific instrument (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire version 3.0). Twenty-four patients (96%) experienced painful or nonpainful phantom rectum syndrome at some point during the first 8 postoperative months. The nonpainful sensations (20 patients) occurred in connection with emptying of feces via the stoma, when performing colostomy irrigation, at rest, or in various positions. Fifteen patients experienced painful sensations, characterized as pins and needles, pain in the perineal area, stinging, and burning occurring mostly in sitting positions. Patients with painful sensations had statistically significant higher scores regarding pain and lower scores for social function than those without painful sensations (P < .031). Phantom rectum symptoms caused worries and concerns and influenced daily life in 29% (n = 5). Phantom rectum syndrome is prevalent in patients undergoing abdominoperineal resection and ostomy creation. Information about phantom rectum syndrome should be shared preoperatively and during follow-up in order to promote optimal quality of life and alleviate bothersome symptoms and concerns associated with phantom rectum syndrome.

Multimodal Narcotic Limited Perioperative Pain Control With Colorectal Surgery

ClinicalTrials.gov

2017-03-16

Colon Cancer; Colon Diverticulosis; Colonic Neoplasms; Colonic Diverticulitis; Pain, Postoperative; Ileus; Ileus Paralytic; Ileus; Mechanical; Constipation Drug Induced; Constipation; Rectum Cancer; Rectum Neoplasm

The action of sennosides and related compounds on human colon and rectum 1

PubMed Central

Hardcastle, J. D.; Wilkins, J. L.

1970-01-01

The direct action of intraluminal senna and related compounds on the human colon and rectum has been investigated. Motility was recorded by balloon kymography with recording units inserted into well established transverse colostomies or into the rectum. The motility of the colon was not changed by intraluminal senna glycosides but the introduction of senna previously incubated with faeces or Esch. coli stimulated the colon to peristalt. The peristalsis was similar to that stimulated by rheinanthrone, an oxanthrone produced by chemical hydrolysis and reduction of senna. Both activated senna and rheinanthrone appeared to act in the colon by contact stimulation. No peristaltic response was stimulated in the rectum, either with activated senna or with rheinanthrone. PMID:4929273

Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study

NASA Astrophysics Data System (ADS)

Zhen, Xin; Chen, Jiawei; Zhong, Zichun; Hrycushko, Brian; Zhou, Linghong; Jiang, Steve; Albuquerque, Kevin; Gu, Xuejun

2017-11-01

Better understanding of the dose-toxicity relationship is critical for safe dose escalation to improve local control in late-stage cervical cancer radiotherapy. In this study, we introduced a convolutional neural network (CNN) model to analyze rectum dose distribution and predict rectum toxicity. Forty-two cervical cancer patients treated with combined external beam radiotherapy (EBRT) and brachytherapy (BT) were retrospectively collected, including twelve toxicity patients and thirty non-toxicity patients. We adopted a transfer learning strategy to overcome the limited patient data issue. A 16-layers CNN developed by the visual geometry group (VGG-16) of the University of Oxford was pre-trained on a large-scale natural image database, ImageNet, and fine-tuned with patient rectum surface dose maps (RSDMs), which were accumulated EBRT  +  BT doses on the unfolded rectum surface. We used the adaptive synthetic sampling approach and the data augmentation method to address the two challenges, data imbalance and data scarcity. The gradient-weighted class activation maps (Grad-CAM) were also generated to highlight the discriminative regions on the RSDM along with the prediction model. We compare different CNN coefficients fine-tuning strategies, and compare the predictive performance using the traditional dose volume parameters, e.g. D 0.1/1/2cc, and the texture features extracted from the RSDM. Satisfactory prediction performance was achieved with the proposed scheme, and we found that the mean Grad-CAM over the toxicity patient group has geometric consistence of distribution with the statistical analysis result, which indicates possible rectum toxicity location. The evaluation results have demonstrated the feasibility of building a CNN-based rectum dose-toxicity prediction model with transfer learning for cervical cancer radiotherapy.

Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study.

PubMed

Zhen, Xin; Chen, Jiawei; Zhong, Zichun; Hrycushko, Brian; Zhou, Linghong; Jiang, Steve; Albuquerque, Kevin; Gu, Xuejun

2017-10-12

Better understanding of the dose-toxicity relationship is critical for safe dose escalation to improve local control in late-stage cervical cancer radiotherapy. In this study, we introduced a convolutional neural network (CNN) model to analyze rectum dose distribution and predict rectum toxicity. Forty-two cervical cancer patients treated with combined external beam radiotherapy (EBRT) and brachytherapy (BT) were retrospectively collected, including twelve toxicity patients and thirty non-toxicity patients. We adopted a transfer learning strategy to overcome the limited patient data issue. A 16-layers CNN developed by the visual geometry group (VGG-16) of the University of Oxford was pre-trained on a large-scale natural image database, ImageNet, and fine-tuned with patient rectum surface dose maps (RSDMs), which were accumulated EBRT  +  BT doses on the unfolded rectum surface. We used the adaptive synthetic sampling approach and the data augmentation method to address the two challenges, data imbalance and data scarcity. The gradient-weighted class activation maps (Grad-CAM) were also generated to highlight the discriminative regions on the RSDM along with the prediction model. We compare different CNN coefficients fine-tuning strategies, and compare the predictive performance using the traditional dose volume parameters, e.g. D 0.1/1/2cc , and the texture features extracted from the RSDM. Satisfactory prediction performance was achieved with the proposed scheme, and we found that the mean Grad-CAM over the toxicity patient group has geometric consistence of distribution with the statistical analysis result, which indicates possible rectum toxicity location. The evaluation results have demonstrated the feasibility of building a CNN-based rectum dose-toxicity prediction model with transfer learning for cervical cancer radiotherapy.

Phantom rectal sensations following abdominoperineal excision of the rectum (APER) and vertical rectus abdominis myocutaneous (VRAM) flap perineal reconstruction.

PubMed

Gould, Charlotte R; Branagan, Graham

2016-11-01

Phantom rectum is the sensation of an intact and/or functioning rectum, despite excision at surgery. Abdominoperineal excision of the rectum (APER) may be complemented by reconstructive operations and recently it was reported that patients undergoing APER and vertical rectus abdominis myocutaneous (VRAM) flap reconstruction are more prone to develop phantom sensations at an earlier timeframe and have more persistent symptoms than those who do not have perineal repairs. The aim of this study was to determine the prevalence of phantom rectal sensations in a cohort of these patients. Patients who underwent APER and VRAM flap reconstruction for anorectal carcinomas were identified from May 2008 to July 2012. Patients completed a questionnaire evaluating their experience of rectal symptoms post-surgery. Thirty-four of 47 eligible patients were enrolled in the study. PR sensations were experienced by 50 % of patients, the majority of which (65 %) were present for >1 year. The commonest sensation reported was the feeling of faeces in a normal rectum (24 %). Disturbances in quality of life were apparent in 44 %; notably, sleep was affected, patients expressed increased feelings of stress/sadness, heightened levels of anxiety and limitation of daily activities as consequences of PR symptoms. Few patients sought medical advice. Fifty percent of patients experience PR sensations post-surgery, comparable with reported data for patients who have undergone APER alone. The addition of VRAM reconstruction does not significantly alter the prevalence of PR symptoms. This paper provides further evidence that phantom rectum occurs frequently and thus all patients undergoing excision of the rectum should be counselled appropriately.

A Monte Carlo study of the impact of the choice of rectum volume definition on estimates of equivalent uniform doses and the volume parameter

NASA Astrophysics Data System (ADS)

Kvinnsland, Yngve; Muren, Ludvig Paul; Dahl, Olav

2004-08-01

Calculations of normal tissue complication probability (NTCP) values for the rectum are difficult because it is a hollow, non-rigid, organ. Finding the true cumulative dose distribution for a number of treatment fractions requires a CT scan before each treatment fraction. This is labour intensive, and several surrogate distributions have therefore been suggested, such as dose wall histograms, dose surface histograms and histograms for the solid rectum, with and without margins. In this study, a Monte Carlo method is used to investigate the relationships between the cumulative dose distributions based on all treatment fractions and the above-mentioned histograms that are based on one CT scan only, in terms of equivalent uniform dose. Furthermore, the effect of a specific choice of histogram on estimates of the volume parameter of the probit NTCP model was investigated. It was found that the solid rectum and the rectum wall histograms (without margins) gave equivalent uniform doses with an expected value close to the values calculated from the cumulative dose distributions in the rectum wall. With the number of patients available in this study the standard deviations of the estimates of the volume parameter were large, and it was not possible to decide which volume gave the best estimates of the volume parameter, but there were distinct differences in the mean values of the values obtained.

Colonoscopy

MedlinePlus

... in which a doctor uses a colonoscope or scope, to look inside your rectum and colon . Colonoscopy ... anus and into your rectum and colon. The scope inflates your large intestine with air for a ...

Flexible Sigmoidoscopy

MedlinePlus

... camera on one end, called a sigmoidoscope or scope, to look inside your rectum and lower colon, ... your rectum and into your sigmoid colon. The scope pumps air into your large intestine to give ...

Relationship between parietal blood flow studies in the left colon and the rectum in dogs. Colonic pressure and blood flow.

PubMed

Arhan, P; Bouchoucha, M; Martelli, H; Rimbert, J N; Berdeaux, A; Gallix, P; Héro, M; Barritault, L; Pellerin, D; Devroede, G

1988-01-01

An animal model was proposed to clarify the difference in occurrence of enterocolitis in congenital aganglionosis. When gaseous distention of the colon was localized to the rectosigmoid area, enterocolitis never occurred. On the contrary, when it involved the left colon, enterocolitis occurred in 13 of 15 patients. Intestinal blood flow rates were simultaneously measured in the left colon and rectum of six dogs by using labeled microspheres and expressed in function of the intraluminal pressure. Results show that for elevated values of intraluminal pressure, blood flow was significantly lower in the left colon than in the rectum. These results may explain why ischemia and necrosis occurred more frequently in the left colon than in the rectum.

Pinworm (for Parents)

MedlinePlus

... the area around the rectum. There, they will lay new pinworm eggs, which trigger itching around the ... move to the area around the rectum to lay their eggs. In girls, pinworm infection can spread ...

The rectum: a window to irritable bowel syndrome?

PubMed

Coremans, G; Azpiroz, F; Collins, S; Dapoigny, M; Müller-Lissner, S A; Pace, F; Smout, A; Stockbrügger, R W; Whorwell, P J

2002-01-01

This report summarizes current concepts and information gathered to date about the rectum in the irritable bowel syndrome (IBS) that were presented at the 10th meeting of IBiS Club held in Leuven, Belgium. A working group of experts in the field of IBS discussed whether the rectum or the whole colon is the better site to test in IBS patients and provided suggestions for a number of areas where further advances are required. Copyright 2002 S. Karger AG, Basel

SU-E-J-103: Propagation of Rectum and Bladder Contours for Tandem and Ring (T&R) HDR Treatment Using Deformable Image Registration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Y; Chao, M; Sheu, R

2015-06-15

Purpose: To investigate the feasibility of using DIR to propagate the manually contoured rectum and bladder from the 1st insertion to the new CT images on subsequent insertions and evaluate the segmentation performance. Methods: Ten cervical cancer patients, who were treated by T&R brachytherapy in 3–4 insertions, were retrospectively collected. In each insertion, rectum and bladder were manually delineated on the planning CT by a physicist and verified by a radiation oncologist. Using VelocityAI (Velocity Medical Solutions, Atlanta, GA), a rigid registration was firstly employed to match the bony structures between the first insertion and each of the following insertions,more » then a multi-pass B-spine DIR was carried out to further map the sub volume that encompasses rectum and bladder. The resultant deformation fields propagated contours, and dice similarity coefficient (DSC) was used to quantitatively evaluate the agreement between the propagated contours and the manually-delineated organs. For the 3rd insertion, we also evaluated if the segmentation performance could be improved by propagating the contours from the most recent insertion, i.e., the 2nd insertion. Results: On average, the contour propagation took about 1 minute. The average and standard deviation of DSC over all insertions and patients was 0.67±0.10 (range: 0.44–0.81) for rectum, and 0.78±0.07 (range: 0.63–0.87) for bladder. For the 3rd insertion, propagating contours from the 2nd insertion could improve the segmentation performance in terms of DSC from 0.63±0.10 to 0.72±0.08 for rectum, and from 0.77±0.07 to 0.79±0.06 for bladder. A Wilcoxon signed rank test indicated that the improvement was statistically significant for rectum (p = 0.004). Conclusion: The preliminary results demonstrate that deformable image registration could efficiently and accurately propagate rectum and bladder contours between CT images in different T&R brachytherapy fractions. We are incorporating the propagated contours into our learning-based method to further segment these organs.« less

Dosimetric evaluation of high-dose-rate interstitial brachytherapy boost treatments for localized prostate cancer.

PubMed

Fröhlich, Georgina; Agoston, Péter; Lövey, József; Somogyi, András; Fodor, János; Polgár, Csaba; Major, Tibor

2010-07-01

To quantitatively evaluate the dose distributions of high-dose-rate (HDR) prostate implants regarding target coverage, dose homogeneity, and dose to organs at risk. Treatment plans of 174 implants were evaluated using cumulative dose-volume histograms (DVHs). The planning was based on transrectal ultrasound (US) imaging, and the prescribed dose (100%) was 10 Gy. The tolerance doses to rectum and urethra were 80% and 120%, respectively. Dose-volume parameters for target (V90, V100, V150, V200, D90, D(min)) and quality indices (DNR [dose nonuniformity ratio], DHI [dose homogeneity index], CI [coverage index], COIN [conformal index]) were calculated. Maximum dose in reference points of rectum (D(r)) and urethra (D(u)), dose to volume of 2 cm(3) of the rectum (D(2ccm)), and 0.1 cm(3) and 1% of the urethra (D(0.1ccm) and D1) were determined. Nonparametric correlation analysis was performed between these parameters. The median number of needles was 16, the mean prostate volume (V(p)) was 27.1 cm(3). The mean V90, V100, V150, and V200 were 99%, 97%, 39%, and 13%, respectively. The mean D90 was 109%, and the D(min) was 87%. The mean doses in rectum and urethra reference points were 75% and 119%, respectively. The mean volumetric doses were D(2ccm) = 49% for the rectum, D(0.1ccm) = 126%, and D1 = 140% for the urethra. The mean DNR was 0.37, while the DHI was 0.60. The mean COIN was 0.66. The Spearman rank order correlation coefficients for volume doses to rectum and urethra were R(D(r),D(2ccm)) = 0.69, R(D(u),D0.(1ccm)) = 0.64, R(D(u),D1) = 0.23. US-based treatment plans for HDR prostate implants based on the real positions of catheters provided acceptable dose distributions. In the majority of the cases, the doses to urethra and rectum were kept below the defined tolerance levels. For rectum, the dose in reference points correlated well with dose-volume parameters. For urethra dose characterization, the use of D1 volumetric parameter is recommended.

Cholecalciferol(25-[OH]-Vitamin D) in Treating Patients With Colorectal Cancer

ClinicalTrials.gov

2014-01-16

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage I Colon Cancer; Stage I Rectal Cancer

Microscopic Colitis: Collagenous Colitis and Lymphocytic Colitis

MedlinePlus

... camera on one end, called a colonoscope or scope, to look inside the rectum and entire colon. ... through the rectum and into the colon. The scope inflates the large intestine with air to give ...

Histological and ultrastructural features of the rectum in Poecilimon cervus Karabağ, 1950 (Orthoptera: Tettigoniidae).

PubMed

Polat, Irmak; Suludere, Zekiye; Candan, Selami

2017-02-01

The morphology and ultrastructure of the rectum in Poecilimon cervus Karabağ, 1950 (Orthoptera, Tettigoniidae) were analyzed by light microscope, scanning (SEM) and transmission electron microscopes (TEM). The rectum is the final part of the digestive tract that plays an important role in water reabsorption in insects and so provides osmoregulation. In the transverse sections, six rectal pads and columnar epithelium can be distinguished. The cuticular intima lines the lumen at the apical side of the epithelium. In the cytoplasm, there are numerous mitochondria, some endocytic vesicles, secreting vesicles whose sizes differ according to the area in the cell, and a nucleus with globular in shape. With this study, we aimed to demonstrate the ultrastructure of the rectum of P. cervus and differences or similarities of with other species. © 2016 Wiley Periodicals, Inc.

Aflibercept and FOLFOX6 Treatment for Previously Untreated Stage IV Colorectal Cancer

ClinicalTrials.gov

2018-05-23

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IV Colon Cancer; Stage IV Rectal Cancer

Rectal prolapse repair - series (image)

MedlinePlus

... the body through the anus. The rectum is anchored in position by ligaments. When these ligaments weaken, the rectum can move out of its normal position, downward, and pass through the anus. This is called rectal prolapse.

Asymptomatic gastric heterotopia in the rectum with Helicobacter pylori infection.

PubMed

Swatek, Jarosław; Wronecki, Lech; Ciechanek, Roman; Szumiło, Justyna

2015-12-01

Gastric heterotopia is very rare in the rectum - less than 50 cases have been reported so far. Only in six of them Helicobacter pylori has been observed in heterotopic mucosa. We report a case of a 58-year-old woman with asymptomatic gastric heterotopia in the rectum, incidentally revealed during colonoscopy as a small, sessile polyp. The presence of H. pylori was confirmed by immunohistochemistry. This finding supports the opinion that H. pylori may pass along the gastrointestinal tract in a viable form and that the fecal-oral route of transmission is possible.

Quantification of Organ Motion During Chemoradiotherapy of Rectal Cancer Using Cone-Beam Computed Tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chong, Irene; Hawkins, Maria; Hansen, Vibeke

2011-11-15

Purpose: There has been no previously published data related to the quantification of rectal motion using cone-beam computed tomography (CBCT) during standard conformal long-course chemoradiotherapy. The purpose of the present study was to quantify the interfractional changes in rectal movement and dimensions and rectal and bladder volume using CBCT and to quantify the bony anatomy displacements to calculate the margins required to account for systematic ({Sigma}) and random ({sigma}) setup errors. Methods and Materials: CBCT images were acquired from 16 patients on the first 3 days of treatment and weekly thereafter. The rectum and bladder were outlined on all CBCTmore » images. The interfraction movement was measured using fixed bony landmarks as references to define the rectal location (upper, mid, and low), The maximal rectal diameter at the three rectal locations was also measured. The bony anatomy displacements were quantified, allowing the calculation of systematic ({Sigma}) and random ({sigma}) setup errors. Results: A total of 123 CBCT data sets were analyzed. Analysis of variance for standard deviation from planning scans showed that rectal anterior and lateral wall movement differed significantly by rectal location. Anterior and lateral rectal wall movements were larger in the mid and upper rectum compared with the low rectum. The posterior rectal wall movement did not change significantly with the rectal location. The rectal diameter changed more in the mid and upper than in the low rectum. No consistent relationship was found between the rectal and bladder volume and time, nor was a significant relationship found between the rectal volume and bladder volume. Conclusions: In the present study, the anterior and lateral rectal movement and rectal diameter were found to change most in the upper rectum, followed by the mid rectum, with the smallest changes seen in the low rectum. Asymmetric margins are warranted to ensure phase 2 coverage.« less

SU-E-T-129: Are Knowledge-Based Planning Dose Estimates Valid for Distensible Organs?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lalonde, R; Heron, D; Huq, M

2015-06-15

Purpose: Knowledge-based planning programs have become available to assist treatment planning in radiation therapy. Such programs can be used to generate estimated DVHs and planning constraints for organs at risk (OARs), based upon a model generated from previous plans. These estimates are based upon the planning CT scan. However, for distensible OARs like the bladder and rectum, daily variations in volume may make the dose estimates invalid. The purpose of this study is to determine whether knowledge-based DVH dose estimates may be valid for distensible OARs. Methods: The Varian RapidPlan™ knowledge-based planning module was used to generate OAR dose estimatesmore » and planning objectives for 10 prostate cases previously planned with VMAT, and final plans were calculated for each. Five weekly setup CBCT scans of each patient were then downloaded and contoured (assuming no change in size and shape of the target volume), and rectum and bladder DVHs were recalculated for each scan. Dose volumes were then compared at 75, 60,and 40 Gy for the bladder and rectum between the planning scan and the CBCTs. Results: Plan doses and estimates matched well at all dose points., Volumes of the rectum and bladder varied widely between planning CT and the CBCTs, ranging from 0.46 to 2.42 for the bladder and 0.71 to 2.18 for the rectum, causing relative dose volumes to vary between planning CT and CBCT, but absolute dose volumes were more consistent. The overall ratio of CBCT/plan dose volumes was 1.02 ±0.27 for rectum and 0.98 ±0.20 for bladder in these patients. Conclusion: Knowledge-based planning dose volume estimates for distensible OARs are still valid, in absolute volume terms, between treatment planning scans and CBCT’s taken during daily treatment. Further analysis of the data is being undertaken to determine how differences depend upon rectum and bladder filling state. This work has been supported by Varian Medical Systems.« less

Spatial features of dose-surface maps from deformably-registered plans correlate with late gastrointestinal complications

NASA Astrophysics Data System (ADS)

Moulton, Calyn R.; House, Michael J.; Lye, Victoria; Tang, Colin I.; Krawiec, Michele; Joseph, David J.; Denham, James W.; Ebert, Martin A.

2017-05-01

This study investigates the associations between spatial distribution of dose to the rectal surface and observed gastrointestinal toxicities after deformably registering each phase of a combined external beam radiotherapy (EBRT)/high-dose-rate brachytherapy (HDRBT) prostate cancer treatment. The study contains data for 118 patients where the HDRBT CT was deformably-registered to the EBRT CT. The EBRT and registered HDRBT TG43 dose distributions in a reference 2 Gy/fraction were 3D-summed. Rectum dose-surface maps (DSMs) were obtained by virtually unfolding the rectum surface slice-by-slice. Associations with late peak gastrointestinal toxicities were investigated using voxel-wise DSM analysis as well as parameterised spatial patterns. The latter were obtained by thresholding DSMs from 1-80 Gy (increment  =  1) and extracting inferior-superior extent, left-right extent, area, perimeter, compactness, circularity and ellipse fit parameters. Logistic regressions and Mann-Whitney U-tests were used to correlate features with toxicities. Rectal bleeding, stool frequency, diarrhoea and urgency/tenesmus were associated with greater lateral and/or longitudinal spread of the high doses near the anterior rectal surface. Rectal bleeding and stool frequency were also influenced by greater low-intermediate doses to the most inferior 20% of the rectum and greater low-intermediate-high doses to 40-80% of the rectum length respectively. Greater low-intermediate doses to the superior 20% and inferior 20% of the rectum length were associated with anorectal pain and urgency/tenesmus respectively. Diarrhoea, completeness of evacuation and proctitis were also related to greater low doses to the posterior side of the rectum. Spatial features for the intermediate-high dose regions such as area, perimeter, compactness, circularity, ellipse eccentricity and confinement to ellipse fits were strongly associated with toxicities other than anorectal pain. Consequently, toxicity is related to the shape of isodoses as well as dose coverage. The findings indicate spatial constraints on doses to certain sections of the rectum may be important for reducing toxicities and optimising dose.

SU-F-T-35: Optimization of Bladder and Rectal Doses Using a Multi-Lumen Intracavitary Applicator for Gynecological Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laoui, S; Dietrich, S; Sehgal, V

2016-06-15

Purpose: Radiation dose delivery for endometrial cancer using HDR techniques is limited by dose to bladder and rectum. A dosimetric study was performed using Varian Capri vaginal brachytherapy applicator to determine the optimal channel configuration which minimizes dose to bladder and rectum, while providing good target coverage. Methods: A total of 17 patients, 63 plans clinically delivered, and 252 simulated plans using Varian BrachyVision planning system were generated to investigate optimal channel configuration which results in minimum dose to bladder and rectum while providing adequate target coverage. The Capri applicator consists of 13 lumens arranged in two concentric rings, onemore » central lumen and six lumens per ring. Manual dose shaping is invariably required to lower the dose to critical organs. Three-dimensional plans were simulated for 4 channel arrangements, all 13 channels, channel 12 o’clock (close to bladder) and 6 o’clock (close to rectum) deactivated, central channel deactivated, and central channel in addition to 12 o’clock and 6 o’clock deactivated. A relationship between V100, the volume that receives the prescribed dose, and the amount of curie-seconds required to deliver it, was established. Results: Using all 13 channels results in maximum dose to bladder and rectum. Deactivating central channel in addition to 12 o’clock and 6 o’clock resulted in minimizing bladder and rectum doses but compromised target coverage. The relationship between V100, the volume that receives the prescribed dose, and the curie seconds was found to be linear. Conclusion: Deactivating channels 12 o’clock and 6 o’clock was shown to be the optimal configuration leading to minimum dose to bladder and rectum without compromising target coverage. The linear relationship between V100 and the curie- seconds can be used as a verification parameter.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boutilier, Justin J., E-mail: j.boutilier@mail.utoronto.ca; Lee, Taewoo; Craig, Tim

Purpose: To develop and evaluate the clinical applicability of advanced machine learning models that simultaneously predict multiple optimization objective function weights from patient geometry for intensity-modulated radiation therapy of prostate cancer. Methods: A previously developed inverse optimization method was applied retrospectively to determine optimal objective function weights for 315 treated patients. The authors used an overlap volume ratio (OV) of bladder and rectum for different PTV expansions and overlap volume histogram slopes (OVSR and OVSB for the rectum and bladder, respectively) as explanatory variables that quantify patient geometry. Using the optimal weights as ground truth, the authors trained and appliedmore » three prediction models: logistic regression (LR), multinomial logistic regression (MLR), and weighted K-nearest neighbor (KNN). The population average of the optimal objective function weights was also calculated. Results: The OV at 0.4 cm and OVSR at 0.1 cm features were found to be the most predictive of the weights. The authors observed comparable performance (i.e., no statistically significant difference) between LR, MLR, and KNN methodologies, with LR appearing to perform the best. All three machine learning models outperformed the population average by a statistically significant amount over a range of clinical metrics including bladder/rectum V53Gy, bladder/rectum V70Gy, and dose to the bladder, rectum, CTV, and PTV. When comparing the weights directly, the LR model predicted bladder and rectum weights that had, on average, a 73% and 74% relative improvement over the population average weights, respectively. The treatment plans resulting from the LR weights had, on average, a rectum V70Gy that was 35% closer to the clinical plan and a bladder V70Gy that was 29% closer, compared to the population average weights. Similar results were observed for all other clinical metrics. Conclusions: The authors demonstrated that the KNN and MLR weight prediction methodologies perform comparably to the LR model and can produce clinical quality treatment plans by simultaneously predicting multiple weights that capture trade-offs associated with sparing multiple OARs.« less

Colorectal Cancer: The Importance of Early Detection

MedlinePlus

... of this page please turn JavaScript on. Feature: Colorectal Cancer The Importance of Early Detection Past Issues / Summer ... Cancer of the colon or rectum is called colorectal cancer. The colon and the rectum are part of ...

Polyps of the Colon and Rectum

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Megarectum in constipation

PubMed Central

van der Plas, R N; Benninga, M; Staalman, C; Akkermans, L; Redekop, W; Taminiau, J; Buller, H

2000-01-01

BACKGROUND—Faecal impaction is frequently observed in children with chronic constipation. The term megarectum is often used to describe this finding.
AIM—To evaluate rectal functioning and rectal measures in constipated children with a filled rectum, in order to define the terms faecal impaction, enlarged rectum, and megarectum.
METHODS—All children underwent radiological investigation, colonic transit time study, anorectal manometry, and rectal volume and rectal wall compliance measurements. Patients with faecal impaction were compared with controls, who had an empty rectum on digital rectal examination.
RESULTS—A total of 31 patients and six controls were included in the study. The mean duration of complaints was 4.2 years and all had faecal incontinence. The colonic transit times in the patients showed a distinct delay in the rectosigmoid segment. Anorectal manometry was not significantly different between patients and controls. The rectal width in patients was 0.68 and in controls 0.52 with an upper limit of 0.61. The pressure-volume curve in patients showed significant less relaxation at a distension of 50 ml. The slope of the curve (corresponding with rectal wall compliance) was comparable for patients and controls.
CONCLUSIONS—We suggest that faecal impaction is a filled rectum found on digital rectal examination; an enlarged rectum is defined by a rectopelvic ratio greater than 0.61; and megarectum is defined in those with significant abnormalities found with anorectal manometry, pressure-volume curves, or rectal compliance investigation. A diminished relaxation of the rectum on rectal distension could be the first sign of megarectum in children with chronic constipation.

 PMID:10869000

Biomechanical and morphological peculiarities of the rectum in patients with obstructed defecation syndrome.

PubMed

Brunenieks, Ints; Pekarska, Katrina; Kasyanov, Vladimir; Groma, Valerija

2017-01-01

The morphological and biomechanical peculiarities of the rectum observed in obstructed defecation syndrome (ODS) are not completely understood. The biomechanical properties and morphological features of the rectum in patients with ODS in correlation with the status of the enteric nervous system (ENS) were evaluated. Uniaxial tensile tests on the rectum samples of patients with ODS and controls were performed; collagenous constituents were assessed by Reticulin and Masson's trichrome stainings; the expressions of α-smooth muscle actin (α-SMA), S100 and CD117 labeling of interstitial cells of Cajal (ICCs) were investigated by immunohistochemistry. In both groups, the ultimate stress in the posterior rectal wall was statistically significantly higher compared to the anterior one. The ultimate strain was higher in ODS compared to controls. The tangential modulus of elasticity was significantly higher in the control group than in the ODS one, both in the anterior and posterior walls. A significantly higher density of collagen demonstrated throughout the wall was evidenced in controls compared to ODS. The mucosal muscular compartment was significantly thicker but more disorganized in the patients group. The enteric S100-positive glial cells were significantly reduced in number in the anterior wall, but elevated in the posterior wall of the rectum in ODS simultaneously demonstrating the higher numbers of ICCs within the entire muscular layer and myenteric. The biomechanical and morphological results show that the rectal wall in patients with ODS is more deformable and less rigid compared to controls. The results of biomechanical properties and morphological changes in the human rectum are essential when choosing the method of ODS treatment.

Nerve supply to the internal anal sphincter differs from that to the distal rectum: an immunohistochemical study of cadavers.

PubMed

Kinugasa, Yusuke; Arakawa, Takashi; Murakami, Gen; Fujimiya, Mineko; Sugihara, Kenichi

2014-04-01

Fecal incontinence is a common problem after anal sphincter-preserving operations. The intersphincteric autonomic nerves supplying the internal anal sphincter (IAS) are formed by the union of: (1) nerve fibers from Auerbach's nerve plexus of the most distal part of the rectum and (2) the inferior rectal branches of the pelvic plexus (IRB-PX) running along the conjoint longitudinal muscle coat. The aim of the present study is to identify the detailed morphology of nerves to the IAS. The study comprised histological and immunohistochemical evaluations of paraffin-embedded sections from a large block of anal canal from the preserved 10 cadavers. The IRB-PX came from the superior aspect of the levator ani and ran into the anal canal on the anterolateral side. These nerves contained both sympathetic and parasympathetic fibers, but the sympathetic content was much higher than in nerves from the distal rectum. All intramural ganglion cells in the distal rectum were neuronal nitric oxide synthase-positive and tyrosine hydroxylase-negative and were restricted to above the squamous-columnar epithelial junction. Parasympathetic nerves formed a lattice-like plexus in the circular smooth muscles of the distal rectum, whereas the IAS contained short, longitudinally running sympathetic and parasympathetic nerves, although sympathetic nerves were dominant. The major autonomic nerve input to the IAS seemed not to originate from the distal rectum but from the IRB-PX. Injury to the IRB-PX during surgery seemed to result in loss of innervation to the major part of the IAS.

SU-F-J-217: Accurate Dose Volume Parameters Calculation for Revealing Rectum Dose-Toxicity Effect Using Deformable Registration in Cervical Cancer Brachytherapy: A Pilot Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhen, X; Chen, H; Liao, Y

Purpose: To study the feasibility of employing deformable registration methods for accurate rectum dose volume parameters calculation and their potentials in revealing rectum dose-toxicity between complication and non-complication cervical cancer patients with brachytherapy treatment. Method and Materials: Data from 60 patients treated with BT including planning images, treatment plans, and follow-up clinical exam were retrospectively collected. Among them, 12 patients complained about hematochezia were further examined with colonoscopy and scored as Grade 1–3 complication (CP). Meanwhile, another 12 non-complication (NCP) patients were selected as a reference group. To seek for potential gains in rectum toxicity prediction when fractional anatomical deformationsmore » are account for, the rectum dose volume parameters D0.1/1/2cc of the selected patients were retrospectively computed by three different approaches: the simple “worstcase scenario” (WS) addition method, an intensity-based deformable image registration (DIR) algorithm-Demons, and a more accurate, recent developed local topology preserved non-rigid point matching algorithm (TOP). Statistical significance of the differences between rectum doses of the CP group and the NCP group were tested by a two-tailed t-test and results were considered to be statistically significant if p < 0.05. Results: For the D0.1cc, no statistical differences are found between the CP and NCP group in all three methods. For the D1cc, dose difference is not detected by the WS method, however, statistical differences between the two groups are observed by both Demons and TOP, and more evident in TOP. For the D2cc, the CP and NCP cases are statistically significance of the difference for all three methods but more pronounced with TOP. Conclusion: In this study, we calculated the rectum D0.1/1/2cc by simple WS addition and two DIR methods and seek for gains in rectum toxicity prediction. The results favor the claim that accurate dose deformation and summation tend to be more sensitive in unveiling the dose-toxicity relationship. This work is supported in part by grant from VARIAN MEDICAL SYSTEMS INC, the National Natural Science Foundation of China (no 81428019 and no 81301940), the Guangdong Natural Science Foundation (2015A030313302)and the 2015 Pearl River S&T Nova Program of Guangzhou (201506010096).« less

Bladder–Rectum Spacer Balloon in High-Dose-Rate Brachytherapy in Cervix Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rai, Bhavana; Patel, Firuza D., E-mail: firuzapatel@gmail.com; Chakraborty, Santam

2013-04-01

Purpose: To compare bladder and rectum doses with the use of a bladder–rectum spacer balloon (BRSB) versus standard gauze packing in the same patient receiving 2 high-dose-rate intracavitary brachytherapy fractions. Methods and Materials: This was a randomized study to compare the reduction in bladder and rectum doses with the use of a BRSB compared with standard gauze packing in patients with carcinoma of the cervix being treated with high-dose-rate intracavitary brachytherapy. The patients were randomized between 2 arms. In arm A, vaginal packing was done with standard gauze packing in the first application, and BRSB was used in the secondmore » application. Arm B was the reverse of arm A. The International Commission for Radiation Units and Measurement (ICRU) point doses and doses to 0.1-cm{sup 3}, 1-cm{sup 3}, 2-cm{sup 3}, 5-cm{sup 3}, and 10-cm{sup 3} volumes of bladder and rectum were compared. The patients were also subjectively assessed for the ease of application and the time taken for application. Statistical analysis was done using the paired t test. Results: A total of 43 patients were enrolled; however, 3 patients had to be excluded because the BRSB could not be inserted owing to unfavorable local anatomy. Thus 40 patients (80 plans) were evaluated. The application was difficult in 3 patients with BRSB, and in 2 patients with BRSB the application time was prolonged. There was no significant difference in bladder doses to 0.1 cm{sup 3}, 1 cm{sup 3}, 2 cm{sup 3}, 5 cm{sup 3}, and 10 cm{sup 3} and ICRU bladder point. Statistically significant dose reductions to 0.1-cm{sup 3}, 1-cm{sup 3}, and 2-cm{sup 3} volumes for rectum were observed with the BRSB. No significant differences in 5-cm{sup 3} and 10-cm{sup 3} volumes and ICRU rectum point were observed. Conclusion: A statistically significant dose reduction was observed for small high-dose volumes in rectum with the BRSB. The doses to bladder were comparable for BRSB and gauze packing. Transparent balloons of variable sizes are recommended for patients with a less spacious vaginal cavity.« less

Colitis cystica profunda of the rectum: An unexpected operative finding

PubMed Central

Ayantunde, Abraham A; Strauss, Claire; Sivakkolunthu, Malathi; Malhotra, Anu

2016-01-01

Colitis cystic profunda is a rare entity benign condition of the colon and rectum that can mimic suspicious polyps or malignancy. The commonest sites of affectation are the rectum and the sigmoid colon but it can be unusually widely distributed in the colon. The aetiology of this condition is not fully elucidated and confident diagnosis can only be made on histological features. We hereby describe a patient who presented with significant rectal symptoms and an unexpected finding of a submucosal mucous cyst mimicking a suspicious rectal polyp and highlighted its significance and the review of the literature. PMID:27458593

Colitis cystica profunda of the rectum: An unexpected operative finding.

PubMed

Ayantunde, Abraham A; Strauss, Claire; Sivakkolunthu, Malathi; Malhotra, Anu

2016-07-16

Colitis cystic profunda is a rare entity benign condition of the colon and rectum that can mimic suspicious polyps or malignancy. The commonest sites of affectation are the rectum and the sigmoid colon but it can be unusually widely distributed in the colon. The aetiology of this condition is not fully elucidated and confident diagnosis can only be made on histological features. We hereby describe a patient who presented with significant rectal symptoms and an unexpected finding of a submucosal mucous cyst mimicking a suspicious rectal polyp and highlighted its significance and the review of the literature.

[A very rare submucosal tumour of the rectum - primary endometrioid adenocarcinoma of the rectum wall].

PubMed

Vogel, Y; Ginsbach, C; Ende, M; Schwering, H; Golz, N; Rieker, O; Hildenbrand, R

2013-01-01

A 56-year-old female, with a past history of hysterectomy 13 years previously due to uterine myomata, presented with complaints of pain around the anus of a few months duration. Three years previously she underwent a colonoscopy, which was found to be unremarkable. A high suspicion of a submucosal tumour of the rectum in endoscopic examinations was confirmed by endoscopic ultrasound. The biopsy could not specify the tumour characteristics. Based on the diagnosis of a 4 cm submucosal tumour with infiltration of bowel wall and regional lymph nodes the affected segment was resected. Histolopathology revealed an adenocarcinoma involving tissue from the outer bowel wall to the submucosa. However, immunohistochemistry revealed an endometrioid adenocarcinoma, suspicious for primary endometrioid adenocarcinoma of the ovary with rectum metastasis in the absence of a uterus. But this assumption could not be confirmed in the excised ovary. The tumour cells were immunopositive for cytokeratin 7, CA 12 - 5, vimentin and oestrogen receptor, but negative for cytokeratin 20 and CDX-2. Ultimately, we report a very rare case of primary endometrioid adenocarcinoma arising in endometriosis in the rectum wall and presenting as a submucosal tumour. © Georg Thieme Verlag KG Stuttgart · New York.

Panitumumab and Chemotherapy in Patients With Advanced Colorectal Cancer After Prior Therapy With Bevacizumab

ClinicalTrials.gov

2018-02-01

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IV Colon Cancer; Stage IV Rectal Cancer

Involvement of shared mucosal-associated microbiota in the duodenum and rectum in diarrhea-predominant irritable bowel syndrome.

PubMed

Li, Gangping; Yang, Min; Jin, Yu; Li, Ying; Qian, Wei; Xiong, Hanhua; Song, Jun; Hou, Xiaohua

2018-06-01

Most studies of diarrhea-predominant irritable bowel syndrome (IBS-D) focused on microbiota dysbiosis in a single segment of the intestine such as the colon. However, the intestine as a whole is involved in IBS-D and knowledge about the role of microbiota shared by the duodenum and rectum in IBS-D is limited. Here, we investigated the characteristics of mucosal microbiota shared by the duodenum and rectum in IBS-D patients. We collected duodenal and rectal mucosal samples from 33 adult IBS-D patients and 15 healthy control (HC) subjects. The 454 pyrosequencing method and multiple bioinformatics analyses were used to examine bacterial 16S rRNA. Clinical data including symptoms and Bristol Stool Form were analyzed. Mucosal microbiota in duodenal samples differed from rectal samples in HC, while less difference was shown in IBS-D. More numbers in terms of shared operational taxonomic units and genera found in IBS-D compared with HC. The frequency of genera in the duodenum and rectum of HC differed from that of IBS-D. We identified 24 genera shared in the duodenum and rectum, which both changed dramatically in IBS-D. Among these 24 genera, half had similar trends in frequency differences, and the other half had opposite trends. The frequency of Faecalibacterium and Hyphomicrobium were associated with clinical data of IBS-D patients. Shared mucosal-associated microbiota in the duodenum and rectum appear to contribute to the etiology and pathophysiology of whole intestine of IBS-D and to be potential therapeutic targets. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Morbidity after Ultra Low Anterior Resection of the Rectum.

PubMed

Straja, N D; Ionescu, S; Brătucu, E; Alecu, M; Simion, L

2015-01-01

Anterior resections of the rectum, used as an alternative to amputation of the rectum, are performed more and more frequently, being presently indicated for neoplasms located ata distance of 7 to 4 cm from the anus. Complications of low and ultra low anterior resections are not at all negligible, and local neoplastic recurrence rate is significantly higher than after amputation of the rectum. However, literature data recommends low and ultra low anterior rectal resections, even if sometimes the method indications are pushed to the limit or the interventions are performed at the patient's request, in order to avoid permanent colostomy. The authors of this article aim to outline a true picture of the changes caused by anterior resections of the rectum, low and ultra low, so that, without denying the merits of these resections, the entire postoperative pathology that occurs in these patients is depicted and understood. Ultra low rectal resections, up to 3-4 cm from the anus, bring important morphological and functional changes to the act of defecation and to anal continence. These changes in colo-anal bowel movement have a much higher incidence than postoperative genitourinary disorders. Another important aspect emerging from the present study is related to the increased incidence of anastomotic disunity, stenosis and various degrees of incontinence, complications that often can only be solved by completion of rectum amputation and permanent colostomy. In addition, the functional outcomes of these ultra low resections are not always at the level expected by the patient. Also, in terms of surgical performance, the higher share of specific complications of the procedure raises questions with regard to the technique. For all these reasons the authors consider it necessary to review the lower limit to which an anterior rectal resection can descend. Celsius.

The role of the rectum in osmoregulation and the potential effect of renoguanylin on SLC26a6 transport activity in the Gulf toadfish (Opsanus beta)

PubMed Central

Takei, Yoshio; Grosell, Martin

2016-01-01

Teleosts living in seawater continually absorb water across the intestine to compensate for branchial water loss to the environment. The present study reveals that the Gulf toadfish (Opsanus beta) rectum plays a comparable role to the posterior intestine in ion and water absorption. However, the posterior intestine appears to rely more on SLC26a6 (a HCO3−/Cl− antiporter) and the rectum appears to rely on NKCC2 (SLC12a1) for the purposes of solute-coupled water absorption. The present study also demonstrates that the rectum responds to renoguanylin (RGN), a member of the guanylin family of peptides that alters the normal osmoregulatory processes of the distal intestine, by inhibited water absorption. RGN decreases rectal water absorption more greatly than in the posterior intestine and leads to net Na+ and Cl− secretion, and a reversal of the absorptive short-circuit current (ISC). It is hypothesized that maintaining a larger fluid volume within the distal segments of intestinal tract facilitates the removal of CaCO3 precipitates and other solids from the intestine. Indeed, the expression of the components of the Cl−-secretory response, apical CFTR, and basolateral NKCC1 (SLC12a2), are upregulated in the rectum of the Gulf toadfish after 96 h in 60 ppt, an exposure that increases CaCO3 precipitate formation relative to 35 ppt. Moreover, the downstream intracellular effects of RGN appear to directly inhibit ion absorption by NKCC2 and anion exchange by SLC26a6. Overall, the present findings elucidate key electrophysiological differences between the posterior intestine and rectum of Gulf toadfish and the potent regulatory role renoguanylin plays in osmoregulation. PMID:27030664

Phase I Study of Neoadjuvant Radiotherapy With 5-Fluorouracil for Rectal Cancer

ClinicalTrials.gov

2017-09-14

Mucinous Adenocarcinoma of the Rectum; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Rectum; Rectal Adenocarcinoma; Stage IIA Rectal Cancer; Stage IIB Rectal Cancer; Stage IIC Rectal Cancer; Stage IIIA Rectal Cancer; Stage IIIB Rectal Cancer; Stage IIIC Rectal Cancer

Chemoembolization Using Irinotecan in Treating Patients With Liver Metastases From Metastatic Colon or Rectal Cancer

ClinicalTrials.gov

2015-09-10

Liver Metastases; Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IV Colon Cancer; Stage IV Rectal Cancer

Metastatic breast cancer to the rectum: A case report with emphasis on MRI features.

PubMed

Lau, Li Ching; Wee, Bernard; Wang, Shi; Thian, Yee Liang

2017-04-01

Less than 1% of breast carcinomas metastasize to the gastrointestinal tract. The diagnosis is frequently not recognized especially when the history of breast carcinoma is remote. A 61-year-old female with a remote history of breast carcinoma presented with a 3-month history of change in bowel habits. Colonoscopy showed a circumferential rectal mass with initial impression of primary rectal cancer. MRI of the rectum showed findings that are atypical for primary rectal cancer. Deep biopsy of the rectal mass confirmed lobular breast carcinoma metastasis to the rectum. The patient was treated with radiotherapy and hormonal therapy. She is symptomatically well 2 years after presentation and remains on hormonal therapy. Lobular breast cancer which metastasizes to the rectum can mimic primary rectal cancer clinically. The unique MRI features described in our case when present with a concordant history of lobular breast carcinoma should alert the radiologist to the possibility of this diagnosis which has important treatment implications.

MRI facilitated a diagnosis of endometriosis of the rectum.

PubMed

Eguchi, S; Komuta, K; Haraguchi, M; Furui, J; Kanematsu, T

2000-01-01

A 51-year-old pre-menopausal Japanese woman suffering from chronic lower abdominal pain was referred to our hospital. A barium enema showed a stenotic lesion in the recto-sigmoid region, and a pelvic computed axial tomography (CAT) scan revealed a thickened rectal wall. A colonoscopic examination showed the rectum to be constrictive, but the mucosa appeared to be intact. Magnetic resonance imaging (MRI) with T1 high-intensity revealed a cystic lesion in the thickened wall of the rectum, which led us to suspect possible bowel endometriosis. Part of the biopsy specimen showed endometrial epithelium within the interstitial layer of histologically normal mucosa; finally, endometriosis of the rectum was diagnosed. The patient became asymptomatic after the initiation of hormonal treatment and later experienced spontaneous menopause. MRI was effective for diagnosis and the patient did not undergo unnecessary laparotomy. Although bowel endometriosis is generally diagnosed by means of resected specimens, in our patient, diagnosis was made using MRI and biopsy, and hormonal therapy had an effective role as a bridge to menopause.

Pelvic and perineal anatomy of the male gorilla: selected observations.

PubMed

Oelrich, T M

1978-08-01

The anatomy of parts of the pelvic outlet and perineum is described in an adult male gorilla. Two previously undescribed muscles are presented: (1) The puborectalis muscle, completely separated from the levator ani, arises from the region of the symphysis and forms a sling for the rectum while it also substitutes for the perineal membrane. (2) The puboampullaris muscle, a paired smooth muscle, arises from the pubis and inserts into the rectum to elevate the rectum while additionally providing support for the urogenital viscera. The levator ani muscle is recounted to point out its lack of attachment to the pelvic viscera while allowing a hiatus in which the rectum is exposed within the perineum. The sphincter urethrae muscle is presented emphasizing its true sphincteric characteristics, its absence of lateral attachments and its similarity to man. Other muscles of the pelvis and perineum as well as urogenital viscera are described or modified where necessary. The manner in which these structures enter into the support of the pelvic viscera is considered.

An improved distance-to-dose correlation for predicting bladder and rectum dose-volumes in knowledge-based VMAT planning for prostate cancer

NASA Astrophysics Data System (ADS)

Wall, Phillip D. H.; Carver, Robert L.; Fontenot, Jonas D.

2018-01-01

The overlap volume histogram (OVH) is an anatomical metric commonly used to quantify the geometric relationship between an organ at risk (OAR) and target volume when predicting expected dose-volumes in knowledge-based planning (KBP). This work investigated the influence of additional variables contributing to variations in the assumed linear DVH-OVH correlation for the bladder and rectum in VMAT plans of prostate patients, with the goal of increasing prediction accuracy and achievability of knowledge-based planning methods. VMAT plans were retrospectively generated for 124 prostate patients using multi-criteria optimization. DVHs quantified patient dosimetric data while OVHs quantified patient anatomical information. The DVH-OVH correlations were calculated for fractional bladder and rectum volumes of 30, 50, 65, and 80%. Correlations between potential influencing factors and dose were quantified using the Pearson product-moment correlation coefficient (R). Factors analyzed included the derivative of the OVH, prescribed dose, PTV volume, bladder volume, rectum volume, and in-field OAR volume. Out of the selected factors, only the in-field bladder volume (mean R  =  0.86) showed a strong correlation with bladder doses. Similarly, only the in-field rectal volume (mean R  =  0.76) showed a strong correlation with rectal doses. Therefore, an OVH formalism accounting for in-field OAR volumes was developed to determine the extent to which it improved the DVH-OVH correlation. Including the in-field factor improved the DVH-OVH correlation, with the mean R values over the fractional volumes studied improving from  -0.79 to  -0.85 and  -0.82 to  -0.86 for the bladder and rectum, respectively. A re-planning study was performed on 31 randomly selected database patients to verify the increased accuracy of KBP dose predictions by accounting for bladder and rectum volume within treatment fields. The in-field OVH led to significantly more precise and fewer unachievable KBP predictions, especially for lower bladder and rectum dose-volumes.

SU-F-J-11: Radiobiologically Optimized Patient Localization During Prostate External Beam Localization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Y; Gardner, S; Liu, C

2016-06-15

Purpose: To present a novel positioning strategy which optimizes radiation delivery with radiobiological response knowledge, and to evaluate its application during prostate external beam radiotherapy. Methods: Ten patients with low or intermediate risk prostate cancer were evaluated retrospectively in this IRB-approved study. For each patient, a VMAT plan was generated on the planning CT (PCT) to deliver 78 Gy in 39 fractions with PTV = prostate + 7 mm margin, except for 5mm in the posterior direction. Five representative pretreatment CBCT images were selected for each patient, and prostate, rectum, and bladder were delineated on all CBCT images. Each CBCTmore » was auto-registered to the corresponding PCT. Starting from this auto-matched position (AM-position), a search for optimal treatment position was performed utilizing a score function based on radiobiological and dosimetric indices (D98-DTV, NTCP-rectum, and NTCP-bladder) for the daily target volume (DTV), rectum, and bladder. DTV was defined as prostate + 4 mm margin to account for intra-fraction motion as well as contouring variability on CBCT. We termed the optimal treatment position the radiobiologically optimized couch shift position (ROCS-position). Results: The indices, averaged over the 10 patients’ treatment plans, were (mean±SD): 77.7±0.2 Gy (D98-PTV), 12.3±2.7% (NTCP-rectum), and 53.2±11.2% (NTCP-bladder). The corresponding values calculated on all 50 CBCT images at the AM-positions were 72.9±11.3 Gy (D98-DTV), 15.8±6.4% (NTCP-rectum), and 53.0±21.1% (NTCP-bladder), respectively. In comparison, calculated on CBCT at the ROCS-positions, the indices were 77.0±2.1 Gy (D98-DTV), 12.1±5.7% (NTCP-rectum), and 60.7±16.4% (NTCP-bladder). Compared to autoregistration, ROCS-optimization recovered dose coverage to target volume and lowered the risk to rectum. Moreover, NTCPrectum for one patient remained high after ROCS-optimization and therefore could potentially benefit from adaptive planning. Conclusion: These encouraging results illustrate the potential utility of applying radiobiologically optimized correction for online image-guided radiotherapy of prostate patients.« less

Radiobiologically optimized couch shift: A new localization paradigm using cone-beam CT for prostate radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Yimei, E-mail: yhuang2@hfhs.org; Gardner, Stephen J.; Wen, Ning

2015-10-15

Purpose: To present a novel positioning strategy which optimizes radiation delivery by utilizing radiobiological response knowledge and evaluate its use during prostate external beam radiotherapy. Methods: Five patients with low or intermediate risk prostate cancer were evaluated retrospectively in this IRB-approved study. For each patient, a VMAT plan with one 358° arc was generated on the planning CT (PCT) to deliver 78 Gy in 39 fractions. Five representative pretreatment cone beam CTs (CBCT) were selected for each patient. The CBCT images were registered to PCT by a human observer, which consisted of an initial automated registration with three degrees-of-freedom, followedmore » by manual adjustment for agreement at the prostate/rectal wall interface. To determine the optimal treatment position for each CBCT, a search was performed centering on the observer-matched position (OM-position) utilizing a score function based on radiobiological and dosimetric indices (EUD{sub prostate}, D99{sub prostate}, NTCP{sub rectum}, and NTCP{sub bladder}) for the prostate, rectum, and bladder. We termed the optimal treatment position the radiobiologically optimized couch shift position (ROCS-position). Results: The dosimetric indices, averaged over the five patients’ treatment plans, were (mean ± SD) 79.5 ± 0.3 Gy (EUD{sub prostate}), 78.2 ± 0.4 Gy (D99{sub prostate}), 11.1% ± 2.7% (NTCP{sub rectum}), and 46.9% ± 7.6% (NTCP{sub bladder}). The corresponding values from CBCT at the OM-positions were 79.5 ± 0.6 Gy (EUD{sub prostate}), 77.8 ± 0.7 Gy (D99{sub prostate}), 12.1% ± 5.6% (NTCP{sub rectum}), and 51.6% ± 15.2% (NTCP{sub bladder}), respectively. In comparison, from CBCT at the ROCS-positions, the dosimetric indices were 79.5 ± 0.6 Gy (EUD{sub prostate}), 77.3 ± 0.6 Gy (D99{sub prostate}), 8.0% ± 3.3% (NTCP{sub rectum}), and 46.9% ± 15.7% (NTCP{sub bladder}). Excessive NTCP{sub rectum} was observed on Patient 5 (19.5% ± 6.6%) corresponding to localization at OM-position, compared to the planned value of 11.7%. This was mitigated with radiobiologically optimized localization, resulting in a reduced NTCP{sub rectum} value of 11.3% ± 3.5%. Overall, the treatment position optimization resulted in similar target dose coverage with reduced risk to rectum. Conclusions: These encouraging results illustrate the potential advantage of applying radiobiologically optimized correction for online image-guided radiotherapy of prostate patients.« less

Evaluation of endorectal ultrasound (ERUS) and MRI for prediction of circumferential resection margin (CRM) for rectal cancer.

PubMed

Tsai, Catherine; Hague, Cameron; Xiong, Wei; Raval, Manoj; Karimuddin, Ahmer; Brown, Carl; Phang, P Terry

2017-05-01

ERUS and MRI are used for preoperative imaging of rectal cancer. Here, we compare ERUS and MRI for accuracy of CRM prediction at mid- and distal rectal locations. In retrospective review, 20 rectal cancer patients having TME surgery had both ERUS and MRI preoperatively: 8 mid rectum and 12 in distal rectum. Predicted CRM by ERUS and MRI were compared to TME pathology. Overall, predicted CRM was 6.5 ± 3.6 mm by ERUS, 7.7 ± 5.0 mm by MRI, and 6.0 ± 4.6 mm by pathology. Overall, correlation coefficients to pathology were 0.77 (p = 0.0004) for ERUS and 0.64 (p = 0.008) for MRI. In distal rectum, correlation coefficients were 0.71 (p = 0.02) for ERUS and -0.10 (p = 0.79) for MRI. In mid rectum, correlation coefficients were 0.92 (p = 0.01) for ERUS and 0.44 (p = 0.38) for MRI. While MRI is used routinely for preoperative rectal cancer imaging, ERUS can provide additional assessment of CRM for mid or distal rectal lesions. Further investigation is needed to support these preliminary ERUS CRM findings in mid and distal rectum. Copyright © 2017 Elsevier Inc. All rights reserved.

Transabdominal Ultrasound Colonography for Detection of Colorectal Neoplasms: Initial Clinical Experience.

PubMed

Liu, Jin-Ya; Chen, Li-Da; Xu, Jian-Bo; Wu, Hui; Ye, Jin-Ning; Zhang, Xin-Hua; Xie, Xiao-Yan; Wang, Wei; Lu, Ming-De

2017-10-01

We investigated the feasibility of using ultrasound colonography (USC) to visualize the healthy colon and rectum and detect colorectal polyps. Eight healthy volunteers underwent USC after standard bowel preparation. The feasibility and image quality of USC in different segments were evaluated. Then, USC was conducted on eight patients with known colonic neoplasms using colonoscopy as the reference standard. For volunteers, USC examinations were successfully performed on four (50.0%) ascending, three (37.5%) transverse and eight (100%) descending colons, as well as all sigmoid colons and rectums. One of four (25.0%) ascending, two of eight (25.0%) descending and all sigmoid colons and rectums were well visualized and free of artifacts. For patients, colonoscopy revealed that eight patients had 17 neoplasms in the distal sigmoid colon and rectum, which included 3 lesions ≤5 mm, 3 lesions 6-9 mm and 11 lesions ≥10 mm. USC visualized 12 of 17 (70.6%) neoplasms. Lesion detection by USC was 0% (0/3), 33.3% (1/3) and 100% (11/11) for neoplasms ≤5, 6-9 mm and ≥10 mm in size. USC can visualize the sigmoid colon and rectum well and detect distal sigmoid and rectal neoplasms ≥10 mm in diameter. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Cystocele and rectal prolapse in a female dog

PubMed Central

Besalti, Omer; Ergin, Irem

2012-01-01

A case of cystocele and prolapsed rectum is reported. The urinary bladder and rectum were repositioned and fixed by cystopexy, colposuspension, and colopexy concurrently. There was no recurrence after 3 months. This is the first report to describe cystocele in a young female dog never having been pregnant. PMID:23729830

Cetuximab and/or Dasatinib in Patients With Colorectal Cancer and Liver Metastases That Can Be Removed by Surgery

ClinicalTrials.gov

2014-05-07

Liver Metastases; Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IV Colon Cancer; Stage IV Rectal Cancer

Sexually transmitted and anorectal infectious diseases.

PubMed

Cone, Molly M; Whitlow, Charles B

2013-12-01

Sexually transmitted diseases (STDs) are common and they can involve the anus and rectum in both men and women. In this article, the main bacterial and viral STDs that affect the anus and rectum are discussed, including their prevalence, presentation, and treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

Phase I-II Study of Fluorouracil in Combination With Phenylbutyrate in Advanced Colorectal Cancer

ClinicalTrials.gov

2013-01-31

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

Genetic Mutations in Blood and Tissue Samples in Predicting Response to Treatment in Patients With Locally Advanced Rectal Cancer Undergoing Chemoradiation

ClinicalTrials.gov

2017-09-08

Mucinous Adenocarcinoma of the Rectum; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Rectum; Stage IIA Rectal Cancer; Stage IIB Rectal Cancer; Stage IIC Rectal Cancer; Stage IIIA Rectal Cancer; Stage IIIB Rectal Cancer; Stage IIIC Rectal Cancer

Ziv-Aflibercept Followed by Ziv-Aflibercept, Fluorouracil, and Leucovorin Calcium in Treating Patients With Stage IV Colorectal Cancer

ClinicalTrials.gov

2015-05-04

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

Targeting MRS-Defined Dominant Intraprostatic Lesions with Inverse-Planned High Dose Rate Brachytherapy

DTIC Science & Technology

2007-02-01

bladder and the rectum are overprotected while the PTV coverage is undesirably reduced. On the other hand, if their maximum dose is increased and/or...B, the bladder and rectum were overprotected with undesirably low PTV coverage (84.54%). The reduction of their weighting factor increased PTV

[Study on the tectology change of rectum wall above the hemorrhoids].

PubMed

Zhang, Li; Yang, Bin; Zhang, Yu-Chao; Fu, Yu-Ru; Chen, Shuang

2009-06-15

To investigate the histomorphological characteristics and its significance of rectum wall above hemorrhoids. Tissues of rectum wall above hemorrhoids were obtained after stapled hemorrhoidopexy from 21 patients with grade III-IV internal hemorrhoids. Seven macroscopically normal rectal tissues collected from upper rectal cancer patients without a history of hemorrhoids served as control. Masson trichrome staining was performed for detecting smooth muscles and collagen in the tissues. The expression of type III collagen was detected by using immunohistochemical staining in the two groups. Morphological abnormalities, such as fragment, rupture, disorganization were found in smooth muscle of proximal rectal tissues above the piles, and it was statistically different from the distal rectal tissues above the piles and control tissues (all P < 0.05). Moreover, hyperplasia of type III collagen in both muscularis mucosa and rectum wall in tissues above hemorrhoids were observed, no such changes was found in the control tissues. The range of pathological changes in hemorrhoids is beyond the anal cushions. The pathological changes of the smooth muscle and the type III collagen in the tissues above the piles are the pathological basis of hemorrhoids.

Burkitt’s Lymphoma of the Rectosigmoid and Stomach Presenting as Hematochezia

PubMed Central

Bustamante-Bernal, Marco; Galvis, Juan; Matos, Dubier; Sosa, Omar; Syed, Saad H.; Padilla, Osvaldo; Davis, Brian; Zuckerman, Marc J.

2016-01-01

Patient: Female, 51 Final Diagnosis: Burkitt’s lymphoma of the rectum and stomach Symptoms: Hematochezia Medication: — Clinical Procedure: EGD and colonoscopy Specialty: Gastroenterology and Hepatology Objective: Rare disease Background: Burkitt’s lymphoma (BL) is an uncommon cause of non-Hodgkin lymphoma in adults and accounts for only 0.1–0.5% of all malignant tumors of the colon and rectum. Very few cases of rectosigmoid and stomach BL have been reported in adults. Case Report: A 51-year-old Hispanic woman presented with a 1-month history of hematochezia, associated with a foreign-body sensation in the rectum and 7 kg weight loss. Initial laboratory workup showed normocytic anemia and positive fecal occult blood. Computed tomography of the abdomen revealed an asymmetric appearance of the stomach and pylorus with nodularity of the mucosa and thickening of the posterior wall, and a 10.8-cm rectal mass. Esophagogastroduodenoscopy and colonoscopy were performed and biopsies of the stomach and rectum were obtained; histopathology demonstrated involvement by Burkitt’s lymphoma in the gastric body nodule and rectal mass. After 4 cycles of chemotherapy, a follow-up abdominal CT demonstrated complete resolution of the mural thickening of the rectum and no intra-abdominal lymphadenopathy. Conclusions: Our case illustrates the importance of considering BL in the extensive differential diagnosis of rectal bleeding, change in bowel habits, and other lower and upper GI symptoms, since the rapidly growing nature of this rare malignancy requires a prompt diagnosis and initiation of appropriate therapy. PMID:26876112

SU-F-J-122: Rectal Sparing Reproducibility in Prostate Cancer Patients Treated with Hydrogel Spacer and Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hedrick, S; Robison, B; Blakey, M

2016-06-15

Purpose: Rectal hydrogel spacer has been shown to improve rectal sparing in prostate radiotherapy. The purpose of this study was to determine the reproducibility of rectal sparing throughout treatment in patients undergoing proton therapy. Methods: At our facility, prostate cancer patients are treated with pencil beam scanning proton therapy, utilizing an endorectal balloon (ERB) or rectal spacer hydrogel (Gel) “SpaceOAR” implant. All patients were treated with a full bladder and empty rectum (low residue diet and stool softeners). A quality assurance CT (QACT) was performed periodically throughout treatment to ensure rectal filling consistency and sparing in 41 patients treated withmore » Gel. The treatment planning (TP) dose was calculated on each QACT and the rectum V90%, V75%, V65%, V50%, and V40% were recorded. QACT scans were acquired on day 0, week 1, week 3, and week 5. Results: 144 QACT scans were analyzed, each patient receiving 3–4 QACTs. Rectum V90% was within +/−1% of the TP dose in 70% of the QACTs and within +/−5% in 95% of scans. From previous data analyses, our ERB rectum V90% average is 6%. This value was used as an upper threshold for the Gel QACT analysis. 5 of the 41 patients (12%), corresponding to 7 QACTs, had a rectum V90% that exceeded 6% on one or more QACTs. However, the average rectal V90% measured over multiple QACTs never exceeded 6%. 55% of the QACTs had a rectum volume within 5cc of the TPCT volume, 68% were within 10cc. Conclusion: In this study, we have shown that a majority of our prostate patients can maintain consistent rectal sparing when treated with a hydrogel spacer. QACT rectal V90% exceeding our threshold was most often related to increased rectal filling and gas, which was addressed with improved dietary compliance and the intensification of stool softeners or laxatives.« less

Is Dose Deformation–Invariance Hypothesis Verified in Prostate IGRT?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simon, Antoine, E-mail: antoine.simon@univ-rennes1.fr; Laboratoire Traitement du Signal et de l'Image, Université de Rennes 1, 35000 Rennes; Le Maitre, Amandine

Purpose: To assess dose uncertainties resulting from the dose deformation–invariance hypothesis in prostate cone beam computed tomography (CT)–based image guided radiation therapy (IGRT), namely to evaluate whether rigidly propagated planned dose distribution enables good estimation of fraction dose distributions. Methods and Materials: Twenty patients underwent a CT scan for planning intensity modulated radiation therapy–IGRT delivering 80 Gy to the prostate, followed by weekly CT scans. Two methods were used to obtain the dose distributions on the weekly CT scans: (1) recalculating the dose using the original treatment plan; and (2) rigidly propagating the planned dose distribution. The cumulative doses were then estimatedmore » in the organs at risk for each dose distribution by deformable image registration. The differences between recalculated and propagated doses were finally calculated for the fraction and the cumulative dose distributions, by use of per-voxel and dose-volume histogram (DVH) metrics. Results: For the fraction dose, the mean per-voxel absolute dose difference was <1 Gy for 98% and 95% of the fractions for the rectum and bladder, respectively. The maximum dose difference within 1 voxel reached, however, 7.4 Gy in the bladder and 8.0 Gy in the rectum. The mean dose differences were correlated with gas volume for the rectum and patient external contour variations for the bladder. The mean absolute differences for the considered volume receiving greater than or equal to dose x (V{sub x}) of the DVH were between 0.37% and 0.70% for the rectum and between 0.53% and 1.22% for the bladder. For the cumulative dose, the mean differences in the DVH were between 0.23% and 1.11% for the rectum and between 0.55% and 1.66% for the bladder. The largest dose difference was 6.86%, for bladder V{sub 80Gy}. The mean dose differences were <1.1 Gy for the rectum and <1 Gy for the bladder. Conclusions: The deformation–invariance hypothesis was corroborated for the organs at risk in prostate IGRT except in cases of a large disappearance or appearance of rectal gas for the rectum and large external contour variations for the bladder.« less

Neural vasodilator control in the rectum of the cat and its possible mediation by vasoactive intestinal polypeptide.

PubMed Central

Andersson, P O; Bloom, S R; Edwards, A V; Järhult, J; Mellander, S

1983-01-01

Vascular and motor responses in the rectum to pelvic nerve stimulation are described in the anaesthetized cat and compared with corresponding effects observed in the colon. The responses comprise a cholinergic and a non-cholinergic component, and an attempt has been made to elucidate the latter. Pelvic nerve stimulation evoked a pronounced and well maintained vasodilator response in the rectum whereas that in the colon was transient. Maximal vasodilatation occurred at much lower stimulus frequencies in the rectum (2-4 Hz) than it did in the colon (8-16 Hz) and maximal blood flow under these conditions was also greater in the rectum (greater than 200 ml 100 g-1 min-1) than the colon (less than 150 ml 100 g-1 min-1). Muscarinic blockade further curtailed the colonic vasodilator response to pelvic nerve stimulation, whereas the rectal dilatation was only slightly reduced in the presence of atropine. Pelvic nerve stimulation caused a substantial release of vasoactive intestinal polypeptide (VIP) from the rectum, which was related both in magnitude and duration to the vasodilatation. Intra-arterial infusions of VIP, which reproduced this rise in rectal venous VIP concentration, caused a rectal vasodilator response which closely resembled that during pelvic nerve stimulation after cholinergic blockade. The rectal vasculature was estimated to be 50-100 times more sensitive to VIP than the colonic vasculature. VIP therefore seems to be the most likely putative neurotransmitter responsible for non-cholinergic rectal vasodilatation. Stimulation of the pelvic nerves also caused rapid contractile motor responses before, and more gradual motor responses after, muscarinic blockade in both the colon and rectum, in the latter preceded by a non-cholinergic relaxation. These patterns of motor activity largely confirm previous results. Infusions of substance P effectively mimicked the non-cholinergic contractile motor responses but failed to demonstrate significant release of this peptide during pelvic nerve stimulation in the present experiments. However, substance P is rapidly inactivated and might possibly be involved in these responses. Stimulation of the pelvic nerves in bursts at high frequencies (up to 80 Hz), simulating a discharge pattern observed electrophysiologically in vivo, was effective in eliciting all the above responses, with the exception of the colonic contraction. PMID:6197521

[Iatrogen perforation of the rectum after colon radiography].

PubMed

Eggum, R; Kressner, U; Haffner, J

1998-05-10

Perforation of the rectum following barium enema is relatively rare, occurring in 1 of 3,000 procedures. Colorectal perforation is a serious condition and early diagnosis is of paramount importance in order to avoid any delay in treating the patient. Direct suture of the perforation, lavage, presacral drainage and stomia are the preferred methods of primary surgical treatment.

Irinotecan-Eluting Beads in Treating Patients With Refractory Metastatic Colon or Rectal Cancer That Has Spread to the Liver

ClinicalTrials.gov

2018-02-22

Liver Metastases; Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

Gastric heterotopia in the rectum. A rare cause of ectopic gastric tissue.

PubMed

Salem, George A; Fazili, Javid; Ali, Tauseef

2017-03-01

Gastric heterotopia refers to the discovery of normal gastric tissue at foreign, unexpected sites. It has been described anywhere in the alimentary tract, even in the mediastinum, scrotum, and spinal cord. It is not uncommonly seen in the oesophagus or small intestine. However, large bowel lesions are rare, with the most common location of colonic lesions is the rectum. Although it is a rare entity, it may be the source for significant problems such as rectal bleeding, abdominal pain, deep rectal pain, and malignancy. Here, we report an additional case of gastric heterotopia in the rectum of a 56year old gentleman, and review the literature. Copyright © 2017 Pan-Arab Association of Gastroenterology. Published by Elsevier B.V. All rights reserved.

Intraluminal irrigation with fibers improves mucosal inflammation and atrophy in diversion colitis.

PubMed

de Oliveira-Neto, Joaquim P; de Aguilar-Nascimento, José E

2004-02-01

We investigated the effect of irrigating the colorectal mucosa of patients with a colostomy using a solution of fibers. Eleven patients (10 male and 1 female; mean age, 34 y; age range, 16-49 y) with loop colostomy due to trauma underwent endoscopic evaluation of the rectum and the proximal and distal mucosa from the colostomy. An endoscopic score (range, 0-10) was used to quantify the intensity of the inflammation at the mucosa. Biopsies were taken from the colostomy border and from the rectum. The mean crypt depth of the five best-oriented glands was registered. Then the diverted colorectal segment was irrigated with a solution containing 5% fibers (10 g/d) for 7 d. The patients underwent repeated endoscopic and biopsy procedures, and then the colostomy was closed. The endoscopic score was higher (P < 0.01) at the distal border (2, 0-5) and the rectum (4, 1-10) when compared with the proximal border (0, 0-1). After treatment, the score at the diverted colon (1, 0-2) diminished (P = 0.03). The macroscopic score of the rectum also decreased after the infusion (4, 1-10, versus 3, 0-4; P = 0.03). Crypt depth at the proximal mucosa was higher than at the diverted mucosa (301 +/- 36 microm versus 205 +/- 76 microm; P < 0.01). After treatment, crypt depth at the diverted mucosa (280 +/- 64 microm) increased (P = 0.03). The rectum mucosa did not change before and after the treatment. Irrigation with fibers improves inflammation at the defunctionalized colon.

A multi-organ biomechanical model to analyze prostate deformation due to large deformation of the rectum

NASA Astrophysics Data System (ADS)

Brock, Kristy K.; Ménard, Cynthia; Hensel, Jennifer; Jaffray, David A.

2006-03-01

Magnetic resonance imaging (MRI) with an endorectal receiver coil (ERC) provides superior visualization of the prostate gland and its surrounding anatomy at the expense of large anatomical deformation. The ability to correct for this deformation is critical to integrate the MR images into the CT-based treatment planning for radiotherapy. The ability to quantify and understand the physiological motion due to large changes in rectal filling can also improve the precision of image-guided procedures. The purpose of this study was to understand the biomechanical relationship between the prostate, rectum, and bladder using a finite element-based multi-organ deformable image registration method, 'Morfeus' developed at our institution. Patients diagnosed with prostate cancer were enrolled in the study. Gold seed markers were implanted in the prostate and MR scans performed with the ERC in place and its surrounding balloon inflated to varying volumes (0-100cc). The prostate, bladder, and rectum were then delineated, converted into finite element models, and assigned appropriate material properties. Morfeus was used to assign surface interfaces between the adjacent organs and deform the bladder and rectum from one position to another, obtaining the position of the prostate through finite element analysis. This approach achieves sub-voxel accuracy of image co-registration in the context of a large ERC deformation, while providing a biomechanical understanding of the multi-organ physiological relationship between the prostate, bladder, and rectum. The development of a deformable registration strategy is essential to integrate the superior information offered in MR images into the treatment planning process.

Failure of Ivermectin per Rectum to Achieve Clinically Meaningful Serum Levels in Two Cases of Strongyloides Hyperinfection

PubMed Central

Bogoch, Isaac I.; Khan, Kamran; Abrams, Howard; Nott, Caroline; Leung, Elizabeth; Fleckenstein, Lawrence; Keystone, Jay S.

2015-01-01

Two cases of Strongyloides hyperinfection are presented. Ivermectin was initially administered orally and per rectum pending the availability of subcutaneous (SC) preparations. In neither case did rectal suppositories of ivermectin achieve clinically meaningful serum values. Clinicians should use SC preparations of ivermectin as early as possible in Strongyloides hyperinfection and dissemination. PMID:25918215

Telomere Length in Predicting Toxicity in Older Patients With Stage III-IV Colorectal Cancer Undergoing Chemotherapy

ClinicalTrials.gov

2018-02-06

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IIIA Colon Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer; Stage IV Colon Cancer; Stage IV Rectal Cancer

Morphology of the epithelium of the lower rectum and the anal canal in the adult human.

PubMed

Tanaka, Eiichi; Noguchi, Tsuyoshi; Nagai, Kaoruko; Akashi, Yuichi; Kawahara, Katsunobu; Shimada, Tatsuo

2012-06-01

The anal canal is an important body part clinically. However, there is no agreement about the epithelium of the anal canal, the anal transitional zone (ATZ) epithelium in particular. The aim of this study is to clarify the structure of the epithelium of the human lower rectum and anal canal. Intact rectum and anus obtained from patients who underwent surgery for rectal carcinoma were examined by light and scanning electron microscopy (LM and SEM). By LM, three types of epithelium were observed in the anal canal: simple columnar epithelium, stratified squamous epithelium, and stratified columnar epithelium. The lower rectum was composed of simple columnar epithelium. SEM findings showed stratified squamous epithelium that consisted of squamous cells with microridges, changing to simple columnar epithelium consisting of columnar cells with short microvilli at the anorectal line. LM and SEM observations in a one-to-one ratio revealed that the area of stratified columnar epithelium based on LM corresponded to the anal crypt and sinus. In conclusion, the epithelium of the human anal canal was fundamentally composed of simple columnar epithelium and stratified squamous epithelium. We found no evidence of the ATZ.

Predicting objective function weights from patient anatomy in prostate IMRT treatment planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Taewoo, E-mail: taewoo.lee@utoronto.ca; Hammad, Muhannad; Chan, Timothy C. Y.

2013-12-15

Purpose: Intensity-modulated radiation therapy (IMRT) treatment planning typically combines multiple criteria into a single objective function by taking a weighted sum. The authors propose a statistical model that predicts objective function weights from patient anatomy for prostate IMRT treatment planning. This study provides a proof of concept for geometry-driven weight determination. Methods: A previously developed inverse optimization method (IOM) was used to generate optimal objective function weights for 24 patients using their historical treatment plans (i.e., dose distributions). These IOM weights were around 1% for each of the femoral heads, while bladder and rectum weights varied greatly between patients. Amore » regression model was developed to predict a patient's rectum weight using the ratio of the overlap volume of the rectum and bladder with the planning target volume at a 1 cm expansion as the independent variable. The femoral head weights were fixed to 1% each and the bladder weight was calculated as one minus the rectum and femoral head weights. The model was validated using leave-one-out cross validation. Objective values and dose distributions generated through inverse planning using the predicted weights were compared to those generated using the original IOM weights, as well as an average of the IOM weights across all patients. Results: The IOM weight vectors were on average six times closer to the predicted weight vectors than to the average weight vector, usingl{sub 2} distance. Likewise, the bladder and rectum objective values achieved by the predicted weights were more similar to the objective values achieved by the IOM weights. The difference in objective value performance between the predicted and average weights was statistically significant according to a one-sided sign test. For all patients, the difference in rectum V54.3 Gy, rectum V70.0 Gy, bladder V54.3 Gy, and bladder V70.0 Gy values between the dose distributions generated by the predicted weights and IOM weights was less than 5 percentage points. Similarly, the difference in femoral head V54.3 Gy values between the two dose distributions was less than 5 percentage points for all but one patient. Conclusions: This study demonstrates a proof of concept that patient anatomy can be used to predict appropriate objective function weights for treatment planning. In the long term, such geometry-driven weights may serve as a starting point for iterative treatment plan design or may provide information about the most clinically relevant region of the Pareto surface to explore.« less

Predicting objective function weights from patient anatomy in prostate IMRT treatment planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Taewoo, E-mail: taewoo.lee@utoronto.ca; Hammad, Muhannad; Chan, Timothy C. Y.

Purpose: Intensity-modulated radiation therapy (IMRT) treatment planning typically combines multiple criteria into a single objective function by taking a weighted sum. The authors propose a statistical model that predicts objective function weights from patient anatomy for prostate IMRT treatment planning. This study provides a proof of concept for geometry-driven weight determination. Methods: A previously developed inverse optimization method (IOM) was used to generate optimal objective function weights for 24 patients using their historical treatment plans (i.e., dose distributions). These IOM weights were around 1% for each of the femoral heads, while bladder and rectum weights varied greatly between patients. Amore » regression model was developed to predict a patient's rectum weight using the ratio of the overlap volume of the rectum and bladder with the planning target volume at a 1 cm expansion as the independent variable. The femoral head weights were fixed to 1% each and the bladder weight was calculated as one minus the rectum and femoral head weights. The model was validated using leave-one-out cross validation. Objective values and dose distributions generated through inverse planning using the predicted weights were compared to those generated using the original IOM weights, as well as an average of the IOM weights across all patients. Results: The IOM weight vectors were on average six times closer to the predicted weight vectors than to the average weight vector, usingl{sub 2} distance. Likewise, the bladder and rectum objective values achieved by the predicted weights were more similar to the objective values achieved by the IOM weights. The difference in objective value performance between the predicted and average weights was statistically significant according to a one-sided sign test. For all patients, the difference in rectum V54.3 Gy, rectum V70.0 Gy, bladder V54.3 Gy, and bladder V70.0 Gy values between the dose distributions generated by the predicted weights and IOM weights was less than 5 percentage points. Similarly, the difference in femoral head V54.3 Gy values between the two dose distributions was less than 5 percentage points for all but one patient. Conclusions: This study demonstrates a proof of concept that patient anatomy can be used to predict appropriate objective function weights for treatment planning. In the long term, such geometry-driven weights may serve as a starting point for iterative treatment plan design or may provide information about the most clinically relevant region of the Pareto surface to explore.« less

SU-E-T-39: A Logistic Function-Based Model to Predict Organ-At-Risk (OAR) DVH in IMRT Treatment Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, S; Zhang, H; Zhang, B

2015-06-15

Purpose: To investigate the feasibility of a logistic function-based model to predict organ-at-risk (OAR) DVH for IMRT planning. The predicted DVHs are compared to achieved DVHs by expert treatment planners. Methods: A logistic function is used to model the OAR dose-gradient function. This function describes the percentage of the prescription dose as a function of the normal distance to PTV surface. The slope of dose-gradient function is function of relative spatial orientation of the PTV and OARs. The OAR DVH is calculated using the OAR dose-gradient function assuming that the dose is same for voxels with same normal distance tomore » PTV. Ten previously planned prostate IMRT plans were selected to build the model, and the following plan parameters were calculated as possible features to the model: the PTV maximum/minimum dose, PTV volume, bladder/rectum volume in the radiation field, percentage of bladder/rectum overlapping with PTV, and the distance between the bladder/rectum centroid and PTV. The bladder/rectum dose-gradient function was modeled and applied on 10 additional test cases, and the predicted and achieved clinical bladder/rectum DVHs were compared: V70 (percentage of volume receiving 70Gy and above), V65, V60, V55, V50, V45, V40. Results: The following parameters were selected as model features: PTV volume, and distance of centroid of rectum/bladder to PTV. The model was tested with 10 additional patients. For bladder, the absolute difference (mean±standard deviation) between predicted and clinical DVHs is V70=−0.3±3.2, V65=−0.8±3.9, V60=1.5±4.3, V55=1.7±5.3, V50=−0.6±6.4, V45=0.6±6.5, and V40=0.9±5.7, the correlation coefficient is 0.96; for rectum, the difference is V70=1.5±3.8, V65=1.2±4.2, V60=−0.1±5.3, V55=1.0±6.6, V50=1.6±8.7, V45=1.9±9.8, and V40=1.5±10.1, and the correlation coefficient is 0.87. Conclusion: The OAR DVH can be accurately predicted using the OAR dose-gradient function in IMRT plans. This approach may be used as a quality control tool and aid less experienced planners determine benchmarks for plan quality.« less

Rare tumors of the rectum. Narrative review.

PubMed

Errasti Alustiza, José; Espín Basany, Eloy; Reina Duarte, Angel

2014-11-01

Most rectal neoplasms are adenocarcinomas, but there is a small percentage of tumors which are of other histological cell lines such as neuroendocrine tumors, sarcomas, lymphomas and squamous cell carcinomas, which have special characteristics and different treatments. We have reviewed these rare tumors of the rectum from a clinical and surgical point of view. Copyright © 2013 AEC. Published by Elsevier Espana. All rights reserved.

Subcutaneous Emphysema Mimicking Gas Gangrene Following Perforation of the Rectum: A Case Report

PubMed Central

Moon, Eun-Sun; Jung, Sung-Taek; Seo, Hyoung-Yeon

2004-01-01

We report a case of extensive subcutaneous emphysema of the lower extremity mimicking gas gangrene following perforation of the rectum in a 38-yr-old man. Subcutaneous emphysema of the leg may rarely occur secondary to perforation of the gastrointestinal tract and has often created serious diagnostic problems and high mortality rates. Therefore, prompt diagnosis and aggressive treatment is imperative. PMID:15483358

Prostate Cancer Detection Using Near Infrared Spectral Polarization Imaging

DTIC Science & Technology

2005-07-01

position. This indicates the polarization preservation nature of Cybesin. Time Resolved Fluorescence Intensity of Cybesin 60000 Perpendicular 3000 0...absorption than that of normal tissue at water absorption peaks indicating cancer tissue has less water content than that of normal tissue; (5) preliminary...rectum-and-membrane tissues.’ This indicates that our proposed approach of imaging a prostate gland through rectum using spectral polarization imaging

Automated generation of IMRT treatment plans for prostate cancer patients with metal hip prostheses: Comparison of different planning strategies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voet, Peter W. J.; Dirkx, Maarten L. P.; Breedveld, Sebastiaan

2013-07-15

Purpose: To compare IMRT planning strategies for prostate cancer patients with metal hip prostheses.Methods: All plans were generated fully automatically (i.e., no human trial-and-error interactions) using iCycle, the authors' in-house developed algorithm for multicriterial selection of beam angles and optimization of fluence profiles, allowing objective comparison of planning strategies. For 18 prostate cancer patients (eight with bilateral hip prostheses, ten with a right-sided unilateral prosthesis), two planning strategies were evaluated: (i) full exclusion of beams containing beamlets that would deliver dose to the target after passing a prosthesis (IMRT{sub remove}) and (ii) exclusion of those beamlets only (IMRT{sub cut}). Plansmore » with optimized coplanar and noncoplanar beam arrangements were generated. Differences in PTV coverage and sparing of organs at risk (OARs) were quantified. The impact of beam number on plan quality was evaluated.Results: Especially for patients with bilateral hip prostheses, IMRT{sub cut} significantly improved rectum and bladder sparing compared to IMRT{sub remove}. For 9-beam coplanar plans, rectum V{sub 60Gy} reduced by 17.5%{+-} 15.0% (maximum 37.4%, p= 0.036) and rectum D{sub mean} by 9.4%{+-} 7.8% (maximum 19.8%, p= 0.036). Further improvements in OAR sparing were achievable by using noncoplanar beam setups, reducing rectum V{sub 60Gy} by another 4.6%{+-} 4.9% (p= 0.012) for noncoplanar 9-beam IMRT{sub cut} plans. Large reductions in rectum dose delivery were also observed when increasing the number of beam directions in the plans. For bilateral implants, the rectum V{sub 60Gy} was 37.3%{+-} 12.1% for coplanar 7-beam plans and reduced on average by 13.5% (maximum 30.1%, p= 0.012) for 15 directions.Conclusions: iCycle was able to automatically generate high quality plans for prostate cancer patients with prostheses. Excluding only beamlets that passed through the prostheses (IMRT{sub cut} strategy) significantly improved OAR sparing. Noncoplanar beam arrangements and, to a larger extent, increasing the number of treatment beams further improved plan quality.« less

Two patients with rare mixed adenoneuroendocrine carcinomas of the rectum.

PubMed

Gül-Klein, Safak; Sinn, Marianne; Jurmeister, Philipp Sebastian; Biebl, Matthias; Weiß, Sascha; Rau, Beate; Bläker, Hendrik; Pratschke, Johann; Aigner, Felix

2018-01-01

Mixed adenoneuroendocrine carcinomas of the gastrointestinal tract are until today poorly understood and thus very challenging for interdisciplinary therapy. We herewith report the first case series of patients with a primary mixed adenoneuroendocrine carcinoma of the rectum. Both cases were initially diagnosed as adenocarcinoma and only secondarily with mixed adenoneuroendocrine carcinoma and had a poor outcome due to a rapid tumor progression and resistance to chemotherapy. A 65-year-old female presented with local tumor recurrence and hepatopulmonary metastasis 1 year after primary surgery for adenocarcinoma of the rectum and consecutive radiochemotherapy regimen. Fluorouracil (5-FU) was followed by bevacizumab- and capecitabine-based chemotherapy but had to be discontinued due to side effects and progressive disease. Progressive local pain syndrome accompanied by recurrent bleeding episodes led to a local tumor-debulking operation. Afterward, mixed adenoneuroendocrine carcinoma as the underlying diagnosis in the final histopathological examination was detected. The patient died 3 months after the operation in the context of a fulminant tumor progress. A 63-year-old male patient underwent neoadjuvant radiochemotherapy and laparoscopic rectum resection. After 5 months, postoperative oxaliplatin/capecitabine-based adjuvant chemotherapy was switched to carboplatin/etopsid due to a progressive polyneuropathy and biopsy-proven pulmonary metastasis. The patient then had to be switched to local radiation of cerebral metastases and Topotecan due to cerebral bleeding episodes but died 18 months after the initial diagnosis. In conclusion of our case series, mixed adenoneuroendocrine carcinomas of the rectum should be considered as a rare but aggressive tumor entity. An early and detailed histopathological diagnosis is required in order to establish an individual interdisciplinary treatment concept.

Human Collagen Injections to Reduce Rectal Dose During Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noyes, William R., E-mail: noyes@cancercenternd.com; Hosford, Charles C.; Schultz, Steven E.

Objectives: The continuing search for interventions, which address the incidence and grade of rectal toxicities associated with radiation treatment of prostate cancer, is a major concern. We are reporting an investigational trial using human collagen to increase the distance between the prostate and anterior rectal wall, thereby decreasing the radiation dose to the rectum. Methods: This is a pilot study evaluating the use of human collagen as a displacing agent for the rectal wall injected before starting a course of intensity-modulated radiotherapy (IMRT) for prostate cancer. Using a transperineal approach, 20 mL of human collagen was injected into the perirectalmore » space in an outpatient setting. Computerized IMRT plans were performed pre- and postcollagen injection, and after a patient completed their radiotherapy, to determine radiation dose reduction to the rectum associated with the collagen injection. Computed tomography scans were performed 6 months and 12 months after completing their radiotherapy to evaluate absorption rate of the collagen. All patients were treated with IMRT to a dose of 75.6 Gy to the prostate. Results: Eleven patients were enrolled into the study. The injection of human collagen in the outpatient setting was well tolerated. The mean separation between the prostate and anterior rectum was 12.7 mm. The mean reduction in dose to the anterior rectal wall was 50%. All men denied any rectal symptoms during the study. Conclusions: The transperineal injection of human collagen for the purpose of tissue displacement is well tolerated in the outpatient setting. The increased separation between the prostate and rectum resulted in a significant decrease in radiation dose to the rectum while receiving IMRT and was associated with no rectal toxicities.« less

Effects of endorphins on different parts of the gastrointestinal tract of rat and guinea-pig in vitro.

PubMed

Nijkamp, F P; Van Ree, J M

1980-04-01

1 The spasmogenic and spasmolytic effects of beta-lipotropin (LPH) fragments and one analogue were investigated on different parts of the gastro-intestinal tract of guinea-pig and rat in vitro.2 Changes in muscle tone were observed in colon and rectum and to a lesser extent in jejunum and ileum of both species. Rat colon and rectum contracted to the peptides. Guinea-pig colon and rectum relaxed after an initial short-lasting contraction.3 On the rat rectum (D-ala(2))met-enkephalin, leu-enkephalin, gamma-endorphin, alpha-endorphin and beta-LPH 80-91 caused dose-dependent contractions, their ED(50) values being 0.96 x 10(-12) mol, 1.05 x 10(-11) mol, 1.22 x 10(-11) mol, 1.08 x 10(-10) mol, 2.65 x 10(-10) mol and 6.5 x 10(-9) mol, respectively.4 Naloxone dose-dependently shifted the dose-response curve of met-enkephalin to the right. Atropine, hexamethonium, burimamide, mepyramine, propranolol and indomethacin did not influence the response to met-enkephalin.5 In the presence of tetrodotoxin, the ED(50) for met-enkephalin and the maximal contractor response induced by met-enkephalin, appeared to be increased.6 The 5-hydroxytryptamine (5-HT) antagonists, methysergide and cyproheptadine, reduced the contractor response in a non-competitive manner. The alpha-adrenoceptor antagonist phentolamine, in contrast, caused an increase of the maximal response to met-enkephalin of up to 200%. Noradrenergic and tryptaminergic systems, therefore, might be involved in the changes in muscle tone induced by met-enkephalin.7 These results demonstrate that rectum and colon of guinea-pig and rat are very sensitive to opioid-like peptides.

Effects of endorphins on different parts of the gastrointestinal tract of rat and guinea-pig in vitro

PubMed Central

Nijkamp, F.P.; Van Ree, J.M.

1980-01-01

1 The spasmogenic and spasmolytic effects of β-lipotropin (LPH) fragments and one analogue were investigated on different parts of the gastro-intestinal tract of guinea-pig and rat in vitro. 2 Changes in muscle tone were observed in colon and rectum and to a lesser extent in jejunum and ileum of both species. Rat colon and rectum contracted to the peptides. Guinea-pig colon and rectum relaxed after an initial short-lasting contraction. 3 On the rat rectum (D-ala2)met-enkephalin, leu-enkephalin, γ-endorphin, α-endorphin and β-LPH 80-91 caused dose-dependent contractions, their ED50 values being 0.96 × 10-12 mol, 1.05 × 10-11 mol, 1.22 × 10-11 mol, 1.08 × 10-10 mol, 2.65 × 10-10 mol and 6.5 × 10-9 mol, respectively. 4 Naloxone dose-dependently shifted the dose-response curve of met-enkephalin to the right. Atropine, hexamethonium, burimamide, mepyramine, propranolol and indomethacin did not influence the response to met-enkephalin. 5 In the presence of tetrodotoxin, the ED50 for met-enkephalin and the maximal contractor response induced by met-enkephalin, appeared to be increased. 6 The 5-hydroxytryptamine (5-HT) antagonists, methysergide and cyproheptadine, reduced the contractor response in a non-competitive manner. The α-adrenoceptor antagonist phentolamine, in contrast, caused an increase of the maximal response to met-enkephalin of up to 200%. Noradrenergic and tryptaminergic systems, therefore, might be involved in the changes in muscle tone induced by met-enkephalin. 7 These results demonstrate that rectum and colon of guinea-pig and rat are very sensitive to opioid-like peptides. PMID:6247000

Magnetic Resonance Imaging (MRI) with retrograde intralumen contrast enhancement of the rectum in diagnostics of rectovaginal fistulas after combination therapy of rectal cancer. Experience of application

NASA Astrophysics Data System (ADS)

Usova, A.; Frolova, I.; Afanasev, S.; Tarasova, A.; Molchanov, S.

2016-02-01

Experiment of use of MRI in diagnostics of rectovaginal fistulas after combination therapy of rectal cancer is shown on clinical examples. We used retrograde contrasting of a rectum with 150ml ultrasonic gel to make MRI more informative in case of low diagnostic efficiency of ultrasound, colonoscopy and gynecological examination.

Arrangement of the myenteric plexus throughout the gastrointestinal tract of the opossum.

PubMed

Christensen, J; Rick, G A; Robison, B A; Stiles, M J; Wix, M A

1983-10-01

Silver impregnation of the myenteric plexus of the opossum gut was used to find differences among various regions. In the esophagus, the plexus was sparse and ganglia were spaced irregularly, many being parafascicular. Ganglia were sparse in the striated-muscle region, but more frequent in the smooth-muscle region. In the stomach, uniformly spaced ganglia were large and intrafascicular; ganglia were larger in the distal stomach than in the proximal stomach. The proximal stomach contained thick fascicles, called shunt fascicles, radiating from the lesser to the greater curvatures and bypassing ganglia. A thick nerve bundle encircled the pylorus. In the small intestine, the regularly spaced ganglia were large and intrafascicular. In the cecum, they were small and intrafascicular. In the colon, they were large and intrafascicular. Shunt fascicles, like those of the proximal stomach, extended from the rectum into the distal colon. In the rectum, the plexus was sparse, and ganglia were small and distributed irregularly. Many ganglia were parafascicular. Unique knots of tangled fascicles were frequent in the rectum; these were called labyrinthine nodes. The least densely innervated regions of the gut are the lower esophageal sphincter and the rectum. Major differences in the anatomy of the plexus characterize the different regions of the gut.

Mobilization of the rectum: anatomic concepts and the bookshelf revisited.

PubMed

Chapuis, Pierre; Bokey, Les; Fahrer, Marius; Sinclair, Gael; Bogduk, Nikolai

2002-01-01

Sound surgical technique is based on accurate anatomic knowledge. In surgery for cancer, the anatomy of the perirectal fascia and the retrorectal plane is the basis for correct mobilization of the rectum to ensure clear surgical margins and to minimize the risk of local recurrence. This review of the literature on the perirectal fascia is based on a translation of the original description by Thoma Jonnesco and a later account by Wilhelm Waldeyer. The Jonnesco description, first published in 1896 in French, is compared with the German account of 1899. These were critically analyzed in the context of our own and other techniques of mobilizing the rectum. Mobilization of the rectum for cancer can be performed along anatomic planes with minimal blood loss, preservation of the pelvic autonomic nerves and a low prevalence of local recurrence. Different techniques including total mesorectal excision are based on the same anatomic principles, however, popular words have been used to replace accepted, established terminology. In particular, the description of total mesorectal excision has been confusing because of its emphasis on the words "total" and "mesorectum." The use of the word "mesorectum" anatomically is inaccurate and the implication that total excision of all the perirectal fat contained within the perirectal fascia "en bloc" in all patients with rectal cancer will minimize local recurrence remains contentious.

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

[Low anterior resection of the rectum with total mesorectal excision--immediate results].

PubMed

Radu, I; Anitei, Gabriela; Scripcariu, V; Dragomir, Cr

2011-01-01

this study was aimed at analyzing the immediate postoperative course in rectal cancer patients who underwent a low anterior resection of the rectum with total mesorectal excision. A retrospective study was carried out on a series of 75 patients operated between January 1, 2004 and December, 31 2010 at the 1lrd Surgical Unit of the Iasi "St. Spiridon" Hospital,. Low anterior resection of the rectum with total mesorectal excision was performed in all the patients. Data from medical files regarding the immediate postoperative course were analyzed. Neoadjuvant therapy was instituted in 32 patients. There were 28 mechanical colorectal anastomoses and 47 manual anastomoses. Protective ileostomy was performed in 46 cases, including I manual anastomosis and 35 mechanical anastomosis cases. Anastomotic fistulas occured in II patients (6 with manual suture and 5 with stapler). Wound complications were identified in 5 cases, while retraction of ileostomy in 2. Two patients died from anastomotic fistula causing abdominal sepsis and multiple organ failure. In both cases ileostomy was performed at the reintervention, concomitantly with drainage of the abdominal abscesses. Healing of the colorectal anastomosis remains the major problem with low anterior resection of the rectum. Protective ileostomy reduces the risk of serious complications in the event of anastomotic fistula.

Burkitt's Lymphoma of the Rectosigmoid and Stomach Presenting as Hematochezia.

PubMed

Bustamante-Bernal, Marco; Galvis, Juan; Matos, Dubier; Sosa, Omar; Syed, Saad H; Padilla, Osvaldo; Davis, Brian; Zuckerman, Marc J

2016-02-15

Burkitt's lymphoma (BL) is an uncommon cause of non-Hodgkin lymphoma in adults and accounts for only 0.1-0.5% of all malignant tumors of the colon and rectum. Very few cases of rectosigmoid and stomach BL have been reported in adults. A 51-year-old Hispanic woman presented with a 1-month history of hematochezia, associated with a foreign-body sensation in the rectum and 7 kg weight loss. Initial laboratory workup showed normocytic anemia and positive fecal occult blood. Computed tomography of the abdomen revealed an asymmetric appearance of the stomach and pylorus with nodularity of the mucosa and thickening of the posterior wall, and a 10.8-cm rectal mass. Esophagogastroduodenoscopy and colonoscopy were performed and biopsies of the stomach and rectum were obtained; histopathology demonstrated involvement by Burkitt's lymphoma in the gastric body nodule and rectal mass. After 4 cycles of chemotherapy, a follow-up abdominal CT demonstrated complete resolution of the mural thickening of the rectum and no intra-abdominal lymphadenopathy. Our case illustrates the importance of considering BL in the extensive differential diagnosis of rectal bleeding, change in bowel habits, and other lower and upper GI symptoms, since the rapidly growing nature of this rare malignancy requires a prompt diagnosis and initiation of appropriate therapy.

Plan selection strategy for rectum cancer patients: An interobserver study to assess clinical feasibility.

PubMed

de Jong, Rianne; Lutkenhaus, Lotte; van Wieringen, Niek; Visser, Jorrit; Wiersma, Jan; Crama, Koen; Geijsen, Debby; Bel, Arjan

2016-08-01

In radiotherapy for rectum cancer, the target volume is highly deformable. An adaptive plan selection strategy can mitigate the effect of these variations. The purpose of this study was to evaluate the feasibility of an adaptive strategy by assessing the interobserver variation in CBCT-based plan selection. Eleven patients with rectum cancer, treated with a non-adaptive strategy, were selected. Five CBCT scans were available per patient. To simulate the plan selection strategy, per patient three PTVs were created by varying the anterior upper mesorectum margin. For each CBCT scan, twenty observers selected the smallest PTV that encompassed the target volume. After this initial baseline measurement, the gold standard was determined during a consensus meeting, followed by a second measurement one month later. Differences between both measurements were assessed using the Wilcoxon signed-rank test. In the baseline measurement, the concordance with the gold standard was 69% (range: 60-82%), which improved to 75% (range: 60-87%) in the second measurement (p=0.01). For the second measurement, 10% of plan selections were smaller than the gold standard. With a plan selection consistency between observers of 75%, a plan selection strategy for rectum cancer patients is feasible. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Forensic medical expertise of injuries in the anorectal region and rectum unrelated to attempts at sexual abuse].

PubMed

Dmitrieva, O A; Smirnova, E V

2011-01-01

The results of analysis of 46 commission forensic medical expertises are presented based on the materials concerning injuries and changes in the anorectal region and rectum unrelated to attempts at sexual abuse. The materials were collected and stored by the Primorskoye territorial Bureau of forensic medical expertise during 5 years, from 2005 to 2009. All injuries and changes were categorized into several groups in terms of their origin, viz. car accidents, inadequate medical care, insertion of foreign bodies, falls on sharp and protruding objects, gunshot wounds, chemical and thermal burns, sports training, etc. The occurrence of the injuries is illustrated by the examples from forensic medical practice. It is concluded that experts describing injuries and changes in the anorectal region and rectum must act in conformity with the order of the Russian Ministry of Health No 346 dated October 21, 2010) and use instrumental methods and terminology accepted in modern proctology. The severity of harm to health in subjects presenting with injuries and changes in the anorectal region and rectum should be evaluated in terms of both the degree of the threat to life and the outcome of the treatment with special reference to the duration of health impairment, severity of the trauma, and its consequences (anorectal dysfunction).

Irinotecan Compared With Combination Chemotherapy in Treating Patients With Advanced Colorectal Cancer

ClinicalTrials.gov

2013-05-01

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IIIA Colon Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

Impact of knee support and shape of tabletop on rectum and prostate position

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steenbakkers, Roel; Duppen, Joop C.; Betgen, Anja

2004-12-01

Purpose: To evaluate the impact of different tabletops with or without a knee support on the position of the rectum, prostate, and bulb of the penis; and to evaluate the effect of these patient-positioning devices on treatment planning. Methods and materials: For 10 male volunteers, five MRI scans were made in four different positions: on a flat tabletop with knee support, on a flat tabletop without knee support, on a rounded tabletop with knee support, and on a rounded tabletop without knee support. The fifth scan was in the same position as the first. With image registration, the position differencesmore » of the rectum, prostate, and bulb of the penis were measured at several points in a sagittal plane through the central axis of the prostate. A planning target volume was generated from the delineated prostates with a margin of 10 mm in three dimensions. A three-field treatment plan with a prescribed dose of 78 Gy to the International Commission on Radiation Units and Measurements point was automatically generated from each planning target volume. Dose-volume histograms were calculated for all rectal walls. Results: The shape of the tabletop did not affect the rectum and prostate position. Addition of a knee support shifted the anterior and posterior rectal walls dorsally. For the anterior rectal wall, the maximum dorsal shift was 9.9 mm (standard error of the mean [SEM] 1.7 mm) at the top of the prostate. For the posterior rectal wall, the maximum dorsal shift was 10.2 mm (SEM 1.5 mm) at the middle of the prostate. Therefore, the rectal filling was pushed caudally when a knee support was added. The knee support caused a rotation of the prostate around the left-right axis at the apex (i.e., a dorsal rotation) by 5.6 deg (SEM 0.8 deg ) and shifts in the caudal and dorsal directions of 2.6 mm (SEM 0.4 cm) and 1.4 mm (SEM 0.6 mm), respectively. The position of the bulb of the penis was not influenced by the use of a knee support or rounded tabletop. The volume of the rectal wall receiving the same dose range (e.g., 40-75 Gy) was reduced by 3.5% (SEM 0.9%) when a knee support was added. No significant differences were observed between the first and fifth scan (flat tabletop with knee support) for all measured points, thereby excluding time trends. Conclusions: The rectum and prostate were significantly shifted dorsally by the use of a knee support. The rectum shifted more than the prostate, resulting in a dose benefit compared with irradiation without knee support. The shape of the tabletop did not influence the rectum or prostate position.« less

SU-E-J-14: A Novel Approach to Evaluate the Dosimetric Effect of Rectal Variation During Image Guided Prostate Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murray, J; McQuaid, D; Dunlop, A

2014-06-01

Purpose: Deformable registration establishes the spatial correspondence back to the reference image in order to accumulate dose. However, in prostate radiotherapy the changing shape and volume of the rectum present a challenge to accurate deformable registration and consequently calculation of delivered dose. We explored an alternative approach to calculating accumulated dose to the rectum, independent of deformable registration. Methods: This study was performed on three patients who received online image-guided radiotherapy (IGRT) with daily CBCT (XVI-system,Elekta) and target localization using intraprostatic fiducials. On each CBCT, the rectum was manually contoured and bulk density assignments were made allowing dose to bemore » calculated for each fraction. Dose-surface maps (DSM) were generated (MATLAB,Mathworks,Natick,MA) by considering the rectum as a cylinder and sampling the dose at 21-equispaced points on each CT slice. The cylinder was “cut” at the posterior-most position on each CT and unfolded to generate a DSM. These were normalised in the longitudinal direction by interpolation creating maps of 21×21 pixels. A DSM was produced for each CBCT and the dose was accumulated. Results: The mean accumulated delivered rectal surface dose was on average 7.5(+/−3.5)% lower than the planned dose. The dose difference maps consistently show that the greatest variation in dose between planned and delivered dose is away from where the rectal surface is adjacent to the prostate. Conclusion: Estimation of dose accumulation using DSM provides an alternative method for determining actual delivered dose to the rectum. The dose difference is greatest in areas away from the region where the rectal surface abuts the prostate, the region where set-up is verified. The change in size and shape of the rectum was shown to resultin a change in the accumulated dose compared to the planned dose and this will have an impact on determining the relationships between dose delivered and toxicity. We acknowledge funding from CRUK and acknowledge NHS funding to the NIHR Biomedical Research Centre for Cancer. Patients were treated within the CHHiP IGRT sub-study (CRUK/06/016, ISRCTN:97182923) funded by CRUK. RayStation was used under an evaluation agreement with RaySearch Laboratories AB.« less

Up-Regulation of Endothelin Type A Receptor in Human and Rat Radiation Proctitis: Preclinical Therapeutic Approach With Endothelin Receptor Blockade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jullien, Nicolash; Blirando, Karl; Milliat, Fabien

2009-06-01

Purpose: Rectum radiation damage and fibrosis are often associated with radiation therapy of pelvic tumors. The endothelin (ET) system has been implicated in several fibrotic diseases but never studied in the context of gastrointestinal radiation damage. This study assessed modifications in ET type 1 (ET-1), ET type A receptor (ET{sub A}), and ET type B receptor (ET{sub B}) localization and/or expression in irradiated human rectal tissue and in a rat model of delayed colorectal injury. We also evaluated the therapeutic potential of long-term ET receptor blockade. Methods and Materials: Routine histological studies of sections of healthy and radiation-injured human rectummore » tissue were done; the sections were also immunostained for ET{sub A} and ET{sub B} receptors. The rat model involved the delivery of 27 Gy in a single dose to the colons and rectums of the animals. The ET-1/ET{sub A}/ET{sub B} expression and ET{sub A}/ET{sub B} localization were studied at 10 weeks postexposure. The abilities of bosentan and atrasentan to protect against delayed rectal injury were also investigated. Results: The immunolocalization of ET{sub A} and ET{sub B} in healthy human rectums was similar to that in rat rectums. However, strong ET{sub A} immunostaining was seen in the presence of human radiation proctitis, and increased ET{sub A} mRNA levels were seen in the rat following colorectal irradiation. Immunostaining for ET{sub A} was also strongly positive in rats in areas of radiation-induced mucosal ulceration, atypia, and fibroproliferation. However, neither bosentan nor atrasentan prevented radiation damage to the rectum when given long term. The only effect seen for atrasentan was an increased number of sclerotic vessel sections in injured tissues. Conclusions: As the result of the overexpression of ET{sub A}, radiation exposure deregulates the endothelin system through an 'ET{sub A} profile' in the human and rodent rectum. However, therapeutic interventions involving mixed or specific ET{sub A} receptor blockade do not prevent radiation damage. Further studies are necessary to identify the precise roles of ET in the gastrointestinal response to radiation exposure.« less

CPI-613 and Fluorouracil in Treating Patients With Metastatic Colorectal Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-04-26

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IIIA Colon Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

[BOWEL ENDOMETRIOSIS - CASE OF RECTAL LOCALISATION.

PubMed

Tsankov, Ts; Zlatkov, V

Endometriosis is a relatively common disease which rarely involves the bowel, and even more rarely occurs with intestinal obstruction. Gastrointestinal tract is involved in 3 to 37% of women with endometriosis such as the frequency is highest in the rectum and the sigma (72%), small intestine (7%), cecum (3.6%) and others. Our case concerns 49 years old woman with a picture of secondary intestinal obsruction, deepening during the last 2-3 months. An anterior resection of the rectum with the closure of the rectal stump has been performed with temporary colostoma - due to the severely inflamed and distended colon as a result of stenosis about 1 cm in diameter involving the portion from the Bauhin's valve to the rectal ampula, caused by two fist-sized tumors in the intestinal wall - on the rear and rear-left side of the rectum. Distally, about 2-3 cm of the tumors, on the anterior wall of the rectum have been found two plaque-like lesions, additionally. The histological result showed that the wall of the colon is engaged by transmural endometriosis, involving the mucosa, muskularis propria and serosa. The case presented differential diagnostic difficulties to exclude malignancy. The benefits of surgical treatment of intestinal endometriosis despite the significant volume of conducted surgery should not be underestimated, as with medication, it significantly improves clinical symptoms and quality of life.

The effect of a probiotic drink with Lactobacillus plantarum 299v on the bacterial composition in faeces and mucosal biopsies of rectum and ascending colon.

PubMed

Goossens, D A M; Jonkers, D M A E; Russel, M G V M; Stobberingh, E E; Stockbrügger, R W

2006-01-15

Studies on probiotics mainly base their results on faecal samples, which may not represent the situation in the mucosa of distal and proximal colon. In a placebo-controlled study, to assess the effect of Lactobacillus plantarum 299v on the bacterial composition of faecal vs. mucosal samples. Twenty-nine patients undergoing colonoscopic examination for polyps consumed a twice-daily drink with or without L. plantarum 299v (10(11) CFU/day) for 2 weeks. Faecal samples were collected before and after consumption. During colonoscopy, biopsies were collected from the ascending colon and rectum. The faecal and mucosal bacterial concentrations and prevalence were determined. L. plantarum 299v significantly increased the concentration of faecal lactic acid bacteria, lactobacilli and clostridia, and was identified in two rectal biopsies but not in the ascending colon biopsies of probiotic-treated subjects. Concentrations and prevalence in ascending colon and rectum biopsies were comparable, but were significantly lower compared with faecal samples. After probiotic consumption, a significant increase in the faecal concentration of lactobacilli was found but concentrations were low in biopsies. The bacterial composition in biopsies of the ascending colon and rectum did not differ based on culture techniques. To further elucidate the modes of action of probiotics, it might be necessary to study differences in colonization with molecular techniques.

Clinical predictors and gender-wise variations in dyssynergic defecation disorders.

PubMed

Jain, Mayank; Baijal, Rajiv; Srinivas, Melpakkam; Venkataraman, Jayanthi

2018-06-12

There is insufficient data from India regarding clinical predictors of dyssynergic defecation. To identify demography, symptom, and colonoscopic parameters that can predict dyssynergic defecation (DD) among patients with chronic constipation (CC) and to compare the profile among male and female patients with DD. Data collected from three centers during June 2014 to May 2017 included age, gender, symptom duration, form and consistency of stools, digital examination, colonoscopy, and anorectal manometry (ARM). Patients were grouped based on ARM diagnosis: group I (normal study) and group II (DD). The two groups were compared for demography, symptom profile, and colonoscopy findings. Gender-wise subset analysis was done for those with the normal and abnormal ARM using chi-square and unpaired t tests. Of 236 patients with CC evaluated, 130 (55%) had normal ARM and 106 (45%) had DD. Male sex, straining during defecation, bleeding per rectum, and abnormal colonoscopic diagnosis were significantly more common in group II. While bleeding per rectum and absence of urge to defecate were more common in males (p < 0.02), straining, digital evacuation, and hard stools were commoner in females with DD. Straining during defecation, bleeding per rectum, and abnormal colonoscopy findings were more common in patients with DD. Symptoms of bleeding per rectum and absence of urge to defecate in men and straining during defecation in female patients were significantly associated with DD. Symptoms differ in males and females with DD.

[Covering stoma in anterior rectum resection with TME for rectal cancer in elderly patients].

PubMed

Cirocchi, Roberto; Grassi, Veronica; Barillaro, Ivan; Cacurri, Alban; Koltraka, Bledar; Coccette, Marco; Sciannameo, Francesco

2010-01-01

The aim of our study is to evaluate the advisability of covering stoma in Anterior Rectum Resection with TME in elderly patients. A research of both the Ministry of Health and Terni Hospital databases has been conducted so as to collect information about patients with rectal tumor. Such research allowed to identify the amount of patients diagnosed with rectal cancer, the type of intervention, and the average hospitalization time. Between January 1997 and June 2008, 209 patients have undergone chirurgical surgery at Terni hospital's General and Emergency Surgical Clinic. An Anterior Rectum Resection with TME has been performed in 135 patients out of the sample (64.59%). The average hospitalization time of geriatric patients does not show significant differences compared to that of younger patients. An age-cohort analysis has been performed among patients who have been subject to stomia and those who have not. The former have been further split up between those who underwent ileostomy and those subject to colostomy. While ileostomy patients face a similar hospitalization time across all age cohorts, geriatric colostomy patients face longer hospitalizations than younger patients. Patients subject to Anterior Rectum Resection show no meaningful differences, in terms of hospitalization time, across all age cohorts. In geriatric patients the construction of covering stoma has resulted in longer hospitalizations only when a loop colostomy was executed, as opposed to loop ileostomy.

Graphic and haptic simulation system for virtual laparoscopic rectum surgery.

PubMed

Pan, Jun J; Chang, Jian; Yang, Xiaosong; Zhang, Jian J; Qureshi, Tahseen; Howell, Robert; Hickish, Tamas

2011-09-01

Medical simulators with vision and haptic feedback techniques offer a cost-effective and efficient alternative to the traditional medical trainings. They have been used to train doctors in many specialties of medicine, allowing tasks to be practised in a safe and repetitive manner. This paper describes a virtual-reality (VR) system which will help to influence surgeons' learning curves in the technically challenging field of laparoscopic surgery of the rectum. Data from MRI of the rectum and real operation videos are used to construct the virtual models. A haptic force filter based on radial basis functions is designed to offer realistic and smooth force feedback. To handle collision detection efficiently, a hybrid model is presented to compute the deformation of intestines. Finally, a real-time cutting technique based on mesh is employed to represent the incision operation. Despite numerous research efforts, fast and realistic solutions of soft tissues with large deformation, such as intestines, prove extremely challenging. This paper introduces our latest contribution to this endeavour. With this system, the user can haptically operate with the virtual rectum and simultaneously watch the soft tissue deformation. Our system has been tested by colorectal surgeons who believe that the simulated tactile and visual feedbacks are realistic. It could replace the traditional training process and effectively transfer surgical skills to novices. Copyright © 2011 John Wiley & Sons, Ltd.

Adaptation to different salinities exposes functional specialization in the intestine of the sea bream (Sparus aurata L.).

PubMed

Gregório, Sílvia F; Carvalho, Edison S M; Encarnação, Sandra; Wilson, Jonathan M; Power, Deborah M; Canário, Adelino V M; Fuentes, Juan

2013-02-01

The processing of intestinal fluid, in addition to a high drinking rate, is essential for osmoregulation in marine fish. This study analyzed the long-term response of the sea bream (Sparus aurata L.) to relevant changes of external salinity (12, 35 and 55 p.p.t.), focusing on the anterior intestine and in the less-often studied rectum. Intestinal water absorption, epithelial HCO(3)(-) secretion and gene expression of the main molecular mechanisms (SLC26a6, SLC26a3, SLC4a4, atp6v1b, CFTR, NKCC1 and NKCC2) involved in Cl(-) and HCO(3)(-) movements were examined. The anion transporters SLC26a6 and SLC26a3 are expressed severalfold higher in the anterior intestine, while the expression of Atp6v1b (V-type H(+)-ATPase β-subunit) is severalfold higher in the rectum. Prolonged exposure to altered external salinity was without effect on water absorption but was associated with concomitant changes in intestinal fluid content, epithelial HCO(3)(-) secretion and salinity-dependent expression of SLC26a6, SLC26a3 and SLC4a4 in the anterior intestine. However, the most striking response to external salinity was obtained in the rectum, where a 4- to 5-fold increase in water absorption was paralleled by a 2- to 3-fold increase in HCO(3)(-) secretion in response to a salinity of 55 p.p.t. In addition, the rectum of high salinity-acclimated fish shows a sustained (and enhanced) secretory current (I(sc)), identified in vitro in Ussing chambers and confirmed by the higher expression of CFTR and NKCC1 and by immunohistochemical protein localization. Taken together, the present results suggest a functional anterior-posterior specialization with regard to intestinal fluid processing and subsequently to salinity adaptation of the sea bream. The rectum becomes more active at higher salinities and functions as the final controller of intestinal function in osmoregulation.

Metastatic spread pattern after curative colorectal cancer surgery. A retrospective, longitudinal analysis.

PubMed

Augestad, K M; Bakaki, P M; Rose, J; Crawshaw, B P; Lindsetmo, R O; Dørum, L M; Koroukian, S M; Delaney, C P

2015-10-01

The most common sites of colorectal cancer (CRC) recurrence are the local tissues, liver or lungs. The objective was to identify risk factors associated with the primary CRC tumor and cancer recurrence in these anatomical sites. Retrospective, longitudinal analyses of data on CRC survivors. Multivariable Cox regression analysis was performed to examine the association between possible cofounders with recurrence to various anatomical sites. Data for 10,398CRC survivors (tumor location right colon=3870, left colon=2898, high rectum=2569, low rectum=1061) were analyzed; follow up time was up to five years. Mean age at curative surgery was 71.5 (SD 11.8) years, 20.2% received radio-chemotherapy, stage T3 (64.4%) and N0 (65.1%) were most common. Overall 1632 (15.7%) had cancer recurrence (Isolated liver n=412, 3,8%;  isolated lung n=252, 2,4%; isolated local n=223, 2.1%). Risk factors associated with recurrent CRC were identified, i.e. isolated liver metastases (male: Adjusted Hazard Ratio (AHR) 1,45; colon left: AHR 1,63; N2 disease: AHR 3,35; T2 disease: AHR 2,82), isolated lung metastases (colon left: AHR 1,53; rectum high: AHR 2,48; rectum low: AHR 2,65; N2 disease 3,76), and local recurrence (glands examined<12: AHR 1,51; CRM <3mm: AHR 1,60; rectum high: AHR 2,15; N2 disease: AHR 2,58) (all p values <0001). Our study finds that the site of the primary CRC tumor is associated with location of subsequent metastasis. Left sided colon cancers have increased risk of metastatic spread to the liver, whereas rectal cancers have increased risk of local recurrence and metastatic spread to the lungs. These results, in combination with other risk factors for CRC recurrence, should be taken into consideration when designing risk adapted post-treatment CRC surveillance programs. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Topographic Anatomy of the Anal Sphincter Complex and Levator Ani Muscle as It Relates to Intersphincteric Resection for Very Low Rectal Disease.

PubMed

Tsukada, Yuichiro; Ito, Masaaki; Watanabe, Kentaro; Yamaguchi, Kumiko; Kojima, Motohiro; Hayashi, Ryuichi; Akita, Keiichi; Saito, Norio

2016-05-01

Intersphincteric resection has become a widely used treatment for patients with rectal cancer. However, the detailed anatomy of the anal canal related to this procedure has remained unclear. The purpose of this study was to clarify the detailed anatomy of the anal canal. This is a descriptive study. Histologic evaluations of paraffin-embedded tissue specimens were conducted at a tertiary referral hospital. Tissue specimens were obtained from cadavers of 5 adults and from 13 patients who underwent abdominoperineal resection for rectal cancer. Sagittal sections from 9 circumferential portions of the cadaveric anal canal (histologic staining) and 3 circumferential portions from patients were studied (immunohistochemistry for smooth and skeletal muscle fibers). Longitudinal fibers between the internal and external anal sphincters consisted primarily of smooth muscle fibers that continued from the longitudinal muscle of the rectum. The levator ani muscle attached directly to the lateral surface of the longitudinal smooth muscle of the rectum. The length of the attachment was longer in the anterolateral portion and shorter in the posterior portion of the anal canal. In the lateral and posterior portions, the levator ani muscle partially overlapped the external anal sphincter; however, there was less overlap in the anterolateral portion. In the posterior portion, thick smooth muscle was present on the surface of the levator ani muscle and it continued to the longitudinal muscle of the rectum. We observed only limited portions in some surgical specimens because of obstruction by tumors. The levator ani muscle attaches directly to the longitudinal muscle of the rectum. The spatial relationship between the smooth and skeletal muscles differed in different portions of the anal canal. For intersphincteric resection, dissection must be performed between the longitudinal muscle of the rectum and the levator ani muscle/external anal sphincter, and the appropriate surgical lines must be selected based on the specific structural characteristics of each portion.

[Progress in the early diagnosis of cancer of the colon and rectum].

PubMed

Canessa, N; Roset, J; Boffi, A; Ferrara, J B; Galano, A; Albertengo, J C

1978-09-01

Our experience with the air contrast examination in the cancer of colon and rectum diagnoses is showed. The colaboration among radiologist, endoscopist, pathologist and surgeon is important. In the large bowel tumors diagnosis, the radiologic and endoscopic prodedures should be evaluated together. The double colonic contrast has showed in our experience, better results than with the barium enema. Over 31 patients with both studies, we obtained 13 false negatives (with barium enema, doing then the double colonic contrast became positive 12 (92.4%).

Simultaneous laparoscopy-assisted low anterior resection and distal gastrectomy for synchronous carcinoma of rectum and stomach

PubMed Central

Zhu, Qian-Lin; Zheng, Min-Hua; Feng, Bo; Lu, Ai-Guo; Wang, Min-Liang; Li, Jian-Wen; Hu, Wei-Guo; Zang, Lu; Mao, Zhi-Hai; Dong, Feng; Ma, Jun-Jun; Zong, Ya-Ping

2008-01-01

Laparoscopic resection of rectal cancer or gastric cancer has been advocated for the benefits of a reduced morbidity, a shorter treatment time, and similar outcomes. However, simultaneous laparoscopy-assisted low anterior resection and distal gastrectomy for synchronous carcinoma of rectum and stomach are rarely documented in literature. Endoscopic examination revealed a synchronous carcinoma of rectum and stomach in a 55-year-old male patient with rectal bleeding and epigastric discomfort. He underwent a simultaneous laparoscopy-assisted low anterior resection and distal gastrectomy with regional lymph nodes dissected. The operation time was 270 min and the estimated blood loss was 120 mL. The patient required parenteral analgesia for less than 24 h. Flatus was passed on postoperative day 3, and a solid diet was resumed on postoperative day 7. He was discharged on postoperative day 13. With the advances in laparoscopic technology and experience, simultaneous resection is an attractive alternative to a synchronous gastrointestinal cancer. PMID:18528944

Virtual reality training and assessment in laparoscopic rectum surgery.

PubMed

Pan, Jun J; Chang, Jian; Yang, Xiaosong; Liang, Hui; Zhang, Jian J; Qureshi, Tahseen; Howell, Robert; Hickish, Tamas

2015-06-01

Virtual-reality (VR) based simulation techniques offer an efficient and low cost alternative to conventional surgery training. This article describes a VR training and assessment system in laparoscopic rectum surgery. To give a realistic visual performance of interaction between membrane tissue and surgery tools, a generalized cylinder based collision detection and a multi-layer mass-spring model are presented. A dynamic assessment model is also designed for hierarchy training evaluation. With this simulator, trainees can operate on the virtual rectum with both visual and haptic sensation feedback simultaneously. The system also offers surgeons instructions in real time when improper manipulation happens. The simulator has been tested and evaluated by ten subjects. This prototype system has been verified by colorectal surgeons through a pilot study. They believe the visual performance and the tactile feedback are realistic. It exhibits the potential to effectively improve the surgical skills of trainee surgeons and significantly shorten their learning curve. Copyright © 2014 John Wiley & Sons, Ltd.

Waugh’s Syndrome: Blessing in Disguise

PubMed Central

Mohanty, Subrat K

2014-01-01

Waugh’s syndrome is the association between intestinal malrotion and intussusceptions. We report a case of Waugh’s syndrome in a one year old child who presented to us with acute bowel obstruction and bleeding per rectum. Due to malrotation, there was easy prolapsing of ileocolic region into the nonfixed ascending colon and the intussusceptum advanced into the descending colon and rectum without compromising vascularity of the bowel. In most of the cases the intussusceptum advancing into the rectum is associated with bowel gangrene even when ceacum is mobile. But in our case, mobile caecum with malrotation proved to be blessing in disguise in preventing such a complication. A Meckel’s diverticulum was also an incidental finding in this case. Waugh's syndrome is missed in cases of close reduction of intussusception and may be a reason for recurrence. Though a rare entity, the probability of Waugh’s syndrome should be kept in mind during surgery, during hydrostatic reduction of intussusceptions, and in case of recurrent ileocolic intussusceptions. PMID:25478404

Waugh's Syndrome: Blessing in Disguise.

PubMed

Behera, Chinmaya Ranjan; Mohanty, Subrat K

2014-10-01

Waugh's syndrome is the association between intestinal malrotion and intussusceptions. We report a case of Waugh's syndrome in a one year old child who presented to us with acute bowel obstruction and bleeding per rectum. Due to malrotation, there was easy prolapsing of ileocolic region into the nonfixed ascending colon and the intussusceptum advanced into the descending colon and rectum without compromising vascularity of the bowel. In most of the cases the intussusceptum advancing into the rectum is associated with bowel gangrene even when ceacum is mobile. But in our case, mobile caecum with malrotation proved to be blessing in disguise in preventing such a complication. A Meckel's diverticulum was also an incidental finding in this case. Waugh's syndrome is missed in cases of close reduction of intussusception and may be a reason for recurrence. Though a rare entity, the probability of Waugh's syndrome should be kept in mind during surgery, during hydrostatic reduction of intussusceptions, and in case of recurrent ileocolic intussusceptions.

Neoadjuvant imatinib treatment and laparoscopic anus-preserving surgery for a large gastrointestinal stromal tumor of the rectum.

PubMed

Kyo, Kennoki; Azuma, Masaki; Okamoto, Kazuya; Nishiyama, Motohiro; Shimamura, Takahiro; Maema, Atsushi; Kanamaru, Hitoshi; Shirakawa, Motoaki; Nakamura, Toshio; Shinmura, Kazuya; Koda, Kenji; Yokoyama, Hidetaro

2016-03-08

Resection of a gastrointestinal stromal tumor (GIST) of the rectum can be difficult because of the particular location in the pelvis, and a large rectal GIST often requires abdominoperineal resection. Recent reports demonstrate that neoadjuvant imatinib treatment improves surgical outcomes in patients with a rectal GIST, and there are only a few reports of the effectiveness of laparoscopic surgery for a rectal GIST. A 46-year-old man was found to have a rectal GIST that measured 80 mm and was located on the anterior wall of the lower rectum. After 6 months treatment with imatinib, the tumor decreased in size to 37 mm, and laparoscopic low anterior resection was performed. The patient is currently alive without any evidence of recurrence 37 months after surgery. Neoadjuvant imatinib should be a treatment of choice for a large rectal GIST. When marked tumor shrinkage is achieved, laparoscopic surgery may be the preferred procedure.

Study of dosimetric variation due to interfraction organ movement in High Dose Rate Interstital (MUPIT) brachytherapy for gynecologic malignancies

NASA Astrophysics Data System (ADS)

Velmurugan, Thanigaimalai; Sukumar, Prabakar; Krishnappan, Chokkalingam; Boopathy, Raghavendiran

2010-01-01

Ten patients with cancer of uterine cervix who underwent interstitial brachytherapy using MUPIT templates were CT scanned (CT1) using which bladder, rectum and CTV were delineated. The treatment plan PCT1 was generated and optimized geometrically on the volume. CT scan (CT2) was repeated before the second fraction of the treatment CTV and critical organs were delineated. The plan (PCT2) was created by reproducing the Plan PCT1 in the CT2 images and compared with PCT1. Bladder, Rectum and CTV percentage volume variation ranges from +28.6% to -34.3%, 38.4% to -14.9% and 8.5% to -15.2% respectively. Maximum dose variation in bladder was +17.1%, in rectum was up to +410% and in CTV was -13.0%. The dose to these structures varies independently with no strong correlation with the volume variation. Hence it is suggested that repeat CT and re-planning is mandatory before second fraction execution.

Regional differences in concentrations of regulatory peptides in human colon mucosal biopsy.

PubMed

Calam, J; Ghatei, M A; Domin, J; Adrian, T E; Myszor, M; Gupta, S; Tait, C; Bloom, S R

1989-08-01

The study was undertaken to examine regional differences in the concentrations of five regulatory peptides in the human colonic mucosa. Biopsies were obtained during routine colonoscopy from 33 patients whose colonic mucosa was macroscopically and histologically normal. Regulatory peptides were extracted, and measured by specific radioimmunoassays. Concentrations of three peptides that are present predominantly in endocrine cells within colonic mucosa increased significantly towards the rectum: Mean concentrations of peptide YY, enteroglucagon, and somatostatin were about three times greater in the rectum than in the cecum. However, concentrations of two peptides that are present in mucosal nerve fibers diminished significantly towards the rectum: Mean rectal concentrations of vasoactive intestinal peptide and peptide histidine methionine were both about 0.6 of mean cecal concentrations. Concentrations of all five peptides were lower in biopsies taken from colonic polyps than in normal colonic mucosa. Regional differences in colonic mucosal concentrations of regulatory peptides probably reflect differences in the physiological functions of different parts of the colon.

IgG4-related disease of the rectum

PubMed Central

Choi, Sung-Bong; Lim, Chul-Hyun; Cha, Myung-Guen

2016-01-01

IgG4-related disease is a relatively new disease entity characterized by elevated serum IgG4 levels and marked infiltration of IgG4-positive plasma cells in lesions. Organ enlargement or nodular lesions consisting of abundant infiltration of lymphocytes and IgG4-positive plasma cells and fibrosis are seen in various organs throughout. We encountered a patient with an inflammatory pseudotumor of the rectum, which was histopathologically confirmed to be an IgG4-related disease. The patient was a 28-year-old woman who had constipation for 3 months. The endoluminal ultrasonography showed a lesion that was heterogeneous and low echogenic in lower rectum. The result of colonoscopic biopsy findings was of chronic proctitis with lymphoid aggregates. For a confirmative diagnosis, excision was performed. Histopathological examination represented plasma cell infiltration and fibrosis. Immunohistochemistry revealed prominence of IgG4-positive plasma cells and confirmed the diagnosis of IgG4-related disease. The patient is currently under observation on low-dose oral prednisolone without relapse. PMID:27186575

Dosimetric impact in the dose-volume histograms of rectal and vesical wall contouring in prostate cancer IMRT treatments.

PubMed

Gómez, Laura; Andrés, Carlos; Ruiz, Antonio

2017-01-01

The main purpose of this study was to evaluate the differences in dose-volume histograms of IMRT treatments for prostate cancer based on the delineation of the main organs at risk (rectum and bladder) as solid organs or by contouring their wall. Rectum and bladder have typically been delineated as solid organs, including the waste material, which, in practice, can lead to an erroneous assessment of the risk of adverse effects. A retrospective study was made on 25 patients treated with IMRT radiotherapy for prostate adenocarcinoma. 76.32 Gy in 36 fractions was prescribed to the prostate and seminal vesicles. In addition to the delineation of the rectum and bladder as solid organs (including their content), the rectal and bladder wall were also delineated and the resulting dose-volume histograms were analyzed for the two groups of structures. Data analysis shows statistically significant differences in the main parameters used to assess the risk of toxicity of a prostate radiotherapy treatment. Higher doses were received on the rectal and bladder walls compared to doses received on the corresponding solid organs. The observed differences in terms of received doses to the rectum and bladder based on the method of contouring could gain greater importance in inverse planning treatments, where the treatment planning system optimizes the dose in these volumes. So, one should take into account the method of delineating of these structures to make a clinical decision regarding dose limitation and risk assessment of chronic toxicity.

[The burden of disease from cancer in Cuba, 1990-2002].

PubMed

Alonso, Emma Domínguez; Jo, Armando H Seuc; Galán, Yaima

2009-11-01

To describe the burden of disease, using morbidity and mortality in Cuba from 1990-2002, by cancer type and location. A descriptive study of the disease burden in the years 1990, 1995, 2000, and 2002, by Cuba's most frequently associated cancer types and locations. Official Cuban sources were used to calculate years of potential life lost (YPLL) due to mortality (based on life expectancy) and morbidity (based on the incidence, average duration, and severity of the disease), as well as years of potential life lost per death (YPLL/D) and the disability-adjusted life years (DALY), for each cancer type and location, by sex and age group. The locations with higher YPLL were also those with the greatest total burden: lung, breast, prostate, colon and rectum, and cervix, and showed an upward trend for all cancer types and locations, except leukemia. The morbidity-related YPLL were concentrated in: breast, lung, prostate, colon and rectum, and cervix. In men, the highest mortality-related YPLL values were in the oral cavity and oropharynx, esophagus, stomach, lung, bladder, melanoma, lymphoma, and leukemia; women were more affected by cancer of the colon and rectum. The highest YPLL/D values were observed for cervix, breast, ovaries, leukemia, and lymphoma. The cancer types and locations with more DALYs were: lung, breast, prostate, colon and rectum, cervix, and endometrium. The burden of disease from cancer increased in Cuba from 1990-2002, mostly due to a rise in the mortality burden.

Site-specific differences in T cell frequencies and phenotypes in the blood and gut of HIV-uninfected and ART-treated HIV+ adults.

PubMed

Yukl, Steven A; Shergill, Amandeep K; Girling, Valerie; Li, Qingsheng; Killian, Maudi; Epling, Lorrie; Li, Peilin; Kaiser, Philipp; Haase, Ashley; Havlir, Diane V; McQuaid, Kenneth; Sinclair, Elizabeth; Wong, Joseph K

2015-01-01

Gastrointestinal T lymphocytes are critical for mucosal immunity and HIV pathogenesis, yet little is known about normal T cell numbers and phenotypes in different regions of the gut, or the degree to which ART can restore levels to those of HIV-uninfected individuals. To investigate these questions, we measured T cell frequencies and markers of memory, activation, anergy, and homing in the blood, ileum, and rectum of HIV- and ART-suppressed HIV+ adults. In HIV- individuals, T cell frequencies and phenotypes differed significantly between sites. Compared to HIV- adults, HIV+ adults had lower absolute CD4+T cell counts in the ileal lamina propria and lower relative CD4+T cell counts in the blood and ileum. In the gut, HIV+ adults had a higher proportion of CD38+ CD4+T cells, a lower proportion of terminally-differentiated effector cells, and, in the rectum, a higher proportion of CTLA-4+ CD4+T cells. In HIV+ individuals, relative CD4+T cell numbers in the ileum correlated with the proportion of CTLA-4+ CD4+T cells, whereas in the rectum, they tended to correlate with the proportion of circulating CD4+T cells expressing α4β7 or CCR6. Mechanisms of T cell reconstitution may differ throughout the gut, with homing contributing more in the rectum while ileal reconstitution is associated with mucosal CD4+T cell anergy.

[Expression of collagen and elastin fibers in the rectum of patients with obstructed defecation syndrome and its significance].

PubMed

Li, Juan; Lin, Hongcheng; Ren, Donglin

2015-12-01

To detect the expression of collagen and elastin fibers in the rectum of patients with obstructive defecation syndrome (ODS), and to explore the possible role of these fibers in the pathogenesis of ODS. The rectum specimens of 20 patients with ODS were collected. These patients had undergone stapled transanal rectal resection (STARR) surgery in our hospital since 2012. Full-thickness rectal specimens were stained with Masson and EVG staining to show collagen and elastin fibers. As the control, rectum specimens of 20 patients with severe prolapsed hemorrhoids also undergoing STARR surgery in our hospital during the same period were collected. Masson staining showed that the structure of collagen fibers in submucosa was slender, area decreased [(13.88±7.02)% vs. (30.98±3.46)%, P<0.01], and the expression level was significantly lower in ODS group compared with control group. EVG staining also showed that collagen fiber area of ODS patients was reduced compared with control group [(17.18±7.24)% vs. (27.04±9.65)%, P<0.01]. Meanwhile EVG staining revealed that elastic fibers were fragmented in ODS group and the expression level was lower compared with control group [(1.20±1.39)% vs. (1.47±1.06)%], whereas the difference was not statistically significant(P>0.05). The expression level of collagen fibers in patients with ODS is significantly reduced, which may play an important role in the pathogenesis of ODS.

Interactive and scale invariant segmentation of the rectum/sigmoid via user-defined templates

NASA Astrophysics Data System (ADS)

Lüddemann, Tobias; Egger, Jan

2016-03-01

Among all types of cancer, gynecological malignancies belong to the 4th most frequent type of cancer among women. Besides chemotherapy and external beam radiation, brachytherapy is the standard procedure for the treatment of these malignancies. In the progress of treatment planning, localization of the tumor as the target volume and adjacent organs of risks by segmentation is crucial to accomplish an optimal radiation distribution to the tumor while simultaneously preserving healthy tissue. Segmentation is performed manually and represents a time-consuming task in clinical daily routine. This study focuses on the segmentation of the rectum/sigmoid colon as an Organ-At-Risk in gynecological brachytherapy. The proposed segmentation method uses an interactive, graph-based segmentation scheme with a user-defined template. The scheme creates a directed two dimensional graph, followed by the minimal cost closed set computation on the graph, resulting in an outlining of the rectum. The graphs outline is dynamically adapted to the last calculated cut. Evaluation was performed by comparing manual segmentations of the rectum/sigmoid colon to results achieved with the proposed method. The comparison of the algorithmic to manual results yielded to a Dice Similarity Coefficient value of 83.85+/-4.08%, in comparison to 83.97+/-8.08% for the comparison of two manual segmentations of the same physician. Utilizing the proposed methodology resulted in a median time of 128 seconds per dataset, compared to 300 seconds needed for pure manual segmentation.

Finite element simulation of interactions between pelvic organs: predictive model of the prostate motion in the context of radiotherapy.

PubMed

Boubaker, Mohamed Bader; Haboussi, Mohamed; Ganghoffer, Jean-François; Aletti, Pierre

2009-08-25

The setting up of predictive models of the pelvic organ motion and deformation may prove an efficient tool in the framework of prostate cancer radiotherapy, in order to deliver doses more accurately and efficiently to the clinical target volume (CTV). A finite element (FE) model of the prostate, rectum and bladder motion has been developed, investigating more specifically the influence of the rectum and bladder repletions on the gland motion. The required organ geometries are obtained after processing the computed tomography (CT) images, using specific softwares. Due to their structural characteristics, a 3D shell discretization is adopted for the rectum and the bladder, whereas a volume discretization is adopted for the prostate. As for the mechanical behavior modelling, first order Ogden hyperelastic constitutive laws for both the rectum and bladder are identified. The prostate is comparatively considered as more rigid and is accordingly modelled as an elastic tissue undergoing small strains. A FE model is then created, accounting for boundary and contact conditions, internal and applied loadings being selected as close as possible to available anatomic data. The order of magnitude of the prostate motion predicted by the FE simulations is similar to the measurements done on a deceased person, accounting for the delineation errors, with a relative error around 8%. Differences are essentially due to uncertainties in the constitutive parameters, pointing towards the need for the setting up of direct measurement of the organs mechanical behavior.

[Endoscopic dilatation of benign colon and rectum stenosis].

PubMed

Rivera Vega, Juan; Frisancho Velarde, Oscar; Cervera, Zenón; Ruiz, Edwin; Yoza, Max; Larrea, Pedro

2002-01-01

To determine the usefulness of endoscopic dilatation in dealing with benign stenosis of the anus, rectum and colon. PATIENTS AND METHODS USED: Thirty six (36) patients with stenosis, anus (8), rectum (22) and colon (6) were given endoscopic treatment using hydroneumatic balloons, electro incision (radiated cuts) or a combination of both. Rigid equipment (metal) was used for distal stenosis. Age ranged between 30 and 82 years. Twelve (12) patients were male and 24 female. The diameter of the stenosis was less than 13 mm in 18 of the patients and 11 patients carried colostomy. All 36 patients were subjected to a total of 113 dilatation sessions. The average number of sessions per patient for patients with anal stenosis was 2.5 and for patients with colorectal stenosis, 3.32. One patient with rectal stenosis required 21 sessions to achieve final objective. The result achieved was good in 31 patients, less than satisfactory in 3 patients and bad in one patient, who presented a stenosis which was over 5 cm long. We lost track of a patient in the follow up stage. Success in closing the colostomy was achieved in 9 patients, while one presented a complication due to the procedure (cervical emphysema) which remitted with medical attention. Endoscopic dilatation offers, through its different techniques, a safe and efficient method for the treatment of benign stenosis of the anus, rectum and colon and must be considered as a first class tool for the treatment of this kind of pathologies.

Measuring the space between vagina and rectum as it relates to rectocele

PubMed Central

Liu, Jin; Zhai, Li-Dong; Li, Yun-Sheng; Liu, Wan-Xiang; Wang, Rui-Hua

2009-01-01

AIM: To measure the normal space between the posterior wall of the vagina and the anterior wall of the respectively rectum using computed tomography (CT) and reveal its were relationship to rectocele. METHODS: A total of twenty female volunteers without rectocele were examined by CT scan. We performed a middle level continuous horizontal pelvic scan from the upper part to the lower part and collected the measurement data to analyze the results using t-test. RESULTS: Twenty volunteers were enrolled in the study. The space between the posterior wall of the vagina and the anterior wall of the rectum was measured at three levels (upper 1/3, middle, lower 1/3 level of vagina). The results showed that the space from the posterior wall of the vagina to the anterior wall of the rectum at the upper 1/3 level and the middle level was 3.896 ± 0.3617 mm and 4.6575 ± 0.3052 mm, respectively. When the two groups of data were compared, we found the space at the upper 1/3 level was shorter than at the middle level (P < 0.01). Moreover, at the lower 1/3 level the space measured was 10.058 ± 0.4534 mm. The results revealed that the space at the lower 1/3 level was longer than that at the middle level (P < 0.01). CONCLUSION: These measurement data may be helpful in assessing rectocele clinical diagnosis and functional outcomes of rectocele repair. PMID:19554660

Impact of database quality in knowledge-based treatment planning for prostate cancer.

PubMed

Wall, Phillip D H; Carver, Robert L; Fontenot, Jonas D

2018-03-13

This article investigates dose-volume prediction improvements in a common knowledge-based planning (KBP) method using a Pareto plan database compared with using a conventional, clinical plan database. Two plan databases were created using retrospective, anonymized data of 124 volumetric modulated arc therapy (VMAT) prostate cancer patients. The clinical plan database (CPD) contained planning data from each patient's clinically treated VMAT plan, which were manually optimized by various planners. The multicriteria optimization database (MCOD) contained Pareto-optimal plan data from VMAT plans created using a standardized multicriteria optimization protocol. Overlap volume histograms, incorporating fractional organ at risk volumes only within the treatment fields, were computed for each patient and used to match new patient anatomy to similar database patients. For each database patient, CPD and MCOD KBP predictions were generated for D 10 , D 30 , D 50 , D 65 , and D 80 of the bladder and rectum in a leave-one-out manner. Prediction achievability was evaluated through a replanning study on a subset of 31 randomly selected database patients using the best KBP predictions, regardless of plan database origin, as planning goals. MCOD predictions were significantly lower than CPD predictions for all 5 bladder dose-volumes and rectum D 50 (P = .004) and D 65 (P < .001), whereas CPD predictions for rectum D 10 (P = .005) and D 30 (P < .001) were significantly less than MCOD predictions. KBP predictions were statistically achievable in the replans for all predicted dose-volumes, excluding D 10 of bladder (P = .03) and rectum (P = .04). Compared with clinical plans, replans showed significant average reductions in D mean for bladder (7.8 Gy; P < .001) and rectum (9.4 Gy; P < .001), while maintaining statistically similar planning target volume, femoral head, and penile bulb dose. KBP dose-volume predictions derived from Pareto plans were more optimal overall than those resulting from manually optimized clinical plans, which significantly improved KBP-assisted plan quality. This work investigates how the plan quality of knowledge databases affects the performance and achievability of dose-volume predictions from a common knowledge-based planning approach for prostate cancer. Bladder and rectum dose-volume predictions derived from a database of standardized Pareto-optimal plans were compared with those derived from clinical plans manually designed by various planners. Dose-volume predictions from the Pareto plan database were significantly lower overall than those from the clinical plan database, without compromising achievability. Copyright © 2018 Elsevier Inc. All rights reserved.

A multiple-image-based method to evaluate the performance of deformable image registration in the pelvis

NASA Astrophysics Data System (ADS)

Saleh, Ziad; Thor, Maria; Apte, Aditya P.; Sharp, Gregory; Tang, Xiaoli; Veeraraghavan, Harini; Muren, Ludvig; Deasy, Joseph

2016-08-01

Deformable image registration (DIR) is essential for adaptive radiotherapy (RT) for tumor sites subject to motion, changes in tumor volume, as well as changes in patient normal anatomy due to weight loss. Several methods have been published to evaluate DIR-related uncertainties but they are not widely adopted. The aim of this study was, therefore, to evaluate intra-patient DIR for two highly deformable organs—the bladder and the rectum—in prostate cancer RT using a quantitative metric based on multiple image registration, the distance discordance metric (DDM). Voxel-by-voxel DIR uncertainties of the bladder and rectum were evaluated using DDM on weekly CT scans of 38 subjects previously treated with RT for prostate cancer (six scans/subject). The DDM was obtained from group-wise B-spline registration of each patient’s collection of repeat CT scans. For each structure, registration uncertainties were derived from DDM-related metrics. In addition, five other quantitative measures, including inverse consistency error (ICE), transitivity error (TE), Dice similarity (DSC) and volume ratios between corresponding structures from pre- and post- registered images were computed and compared with the DDM. The DDM varied across subjects and structures; DDMmean of the bladder ranged from 2 to 13 mm and from 1 to 11 mm for the rectum. There was a high correlation between DDMmean of the bladder and the rectum (Pearson’s correlation coefficient, R p  =  0.62). The correlation between DDMmean and the volume ratios post-DIR was stronger (R p  =  0.51 0.68) than the correlation with the TE (bladder: R p  =  0.46 rectum: R p  =  0.47), or the ICE (bladder: R p  =  0.34 rectum: R p  =  0.37). There was a negative correlation between DSC and DDMmean of both the bladder (R p  =  -0.23) and the rectum (R p  =  -0.63). The DDM uncertainty metric indicated considerable DIR variability across subjects and structures. Our results show a stronger correlation with volume ratios and with the DSC using DDM compared to using ICE and TE. The DDM has the potential to quantitatively identify regions of large DIR uncertainties and consequently identify anatomical/scan outliers. The DDM can, thus, be applied to improve the adaptive RT process for tumor sites subject to motion.

Granulocytic sarcoma of the rectum: a rare complication of myelodysplasia.

PubMed Central

Dabbagh, V; Browne, G; Parapia, L A; Price, J J; Batman, P A

1999-01-01

A 67 year old man with myelodysplasia was admitted as an emergency with a six week history of rectal bleeding and diarrhoea. Barium enema showed an irregular polypoid filling defect in the lateral wall of the proximal rectum near the rectosigmoid junction. Histology showed this to be a granulocytic sarcoma (extramedullary granulocytic leukaemia; chloroma) infiltrating the bowel. A low index of suspicion of this lesion results in an incorrect diagnosis in many such cases. A chloroacetate esterase immunoperoxidase stain will confirm the granulocytic nature of the tumour cells. Images PMID:10690184

Colonic motility in proctalgia fugax.

PubMed

Harvey, R F

1979-10-06

Intraluminal pressure recordings were obtained from the rectum and sigmoid colon in two patients experiencing attacks of proctalgia fugax. In each patient the pain appeared to result from contractions of the sigmoid colon, and not from spasm of the levator ani, rectal wall muscle, or anal sphincters, all of which have previously been suggested as the source of such pain. Proctalgia fugax therefore appears, at least in some patients, to be an unusual variant of the irritable bowel syndrome, in which pain is referred from the sigmoid colon to the rectum.

Absorption of 5-aminosalicylic acid from colon and rectum.

PubMed Central

Bondesen, S; Schou, J B; Pedersen, V; Rafiolsadat, Z; Hansen, S H; Hvidberg, E F

1988-01-01

In order to clarify the characteristics of absorption of 5-aminosalicylic acid (5-ASA) from the colon, a neutral solution was instilled into the right part of the colon and the rectum, respectively, in six volunteers. A laxative (bisacodyl) and liquid meals were given prior to each instillation. No significant difference could be demonstrated between the two parts of the large bowel, but the absorption was considerably restricted compared with previous results obtained from the jejunum. The results confirm in a direct manner earlier observations on 5-ASA released from sulphasalazine. PMID:3358890

Comparative evaluation of two-dimensional radiography and three dimensional computed tomography based dose-volume parameters for high-dose-rate intracavitary brachytherapy of cervical cancer: a prospective study.

PubMed

Madan, Renu; Pathy, Sushmita; Subramani, Vellaiyan; Sharma, Seema; Mohanti, Bidhu Kalyan; Chander, Subhash; Thulkar, Sanjay; Kumar, Lalit; Dadhwal, Vatsla

2014-01-01

Dosimetric comparison of two dimensional (2D) radiography and three-dimensional computed tomography (3D-CT) based dose distributions with high-dose-rate (HDR) intracavitry radiotherapy (ICRT) for carcinoma cervix, in terms of target coverage and doses to bladder and rectum. Sixty four sessions of HDR ICRT were performed in 22 patients. External beam radiotherapy to pelvis at a dose of 50 Gray in 27 fractions followed by HDR ICRT, 21 Grays to point A in 3 sessions, one week apart was planned . All patients underwent 2D-orthogonal and 3D-CT simulation for each session. Treatment plans were generated using 2D-orthogonal images and dose prescription was made at point A. 3D plans were generated using 3D-CT images after delineating target volume and organs at risk. Comparative evaluation of 2D and 3D treatment planning was made for each session in terms of target coverage (dose received by 90%, 95% and 100% of the target volume: D90, D95 and D100 respectively) and doses to bladder and rectum: ICRU-38 bladder and rectum point dose in 2D planning and dose to 0.1cc, 1cc, 2cc, 5cc, and 10cc of bladder and rectum in 3D planning. Mean doses received by 100% and 90% of the target volume were 4.24 ± 0.63 and 4.9 ± 0.56 Gy respectively. Doses received by 0.1cc, 1cc and 2cc volume of bladder were 2.88 ± 0.72, 2.5 ± 0.65 and 2.2 ± 0.57 times more than the ICRU bladder reference point. Similarly, doses received by 0.1cc, 1cc and 2cc of rectum were 1.80 ± 0.5, 1.48 ± 0.41 and 1.35 ± 0.37 times higher than ICRU rectal reference point. Dosimetric comparative evaluation of 2D and 3D CT based treatment planning for the same brachytherapy session demonstrates underestimation of OAR doses and overestimation of target coverage in 2D treatment planning.

Analyse des facteurs histo-pronostiques du cancer du rectum non métastatique dans une série ouest Algérienne de 58 cas au CHU-Tlemcen

PubMed Central

Mesli, Smain Nabil; Regagba, Derbali; Tidjane, Anisse; Benkalfat, Mokhtar; Abi-Ayad, Chakib

2016-01-01

Introduction L'objectif de notre travail est d'analyser les facteurs histo-pronostiques des cancers du rectum non métastatique opérés au service de chirurgie «A» de Tlemcen à ouest Algérien durant une période de six ans. Méthodes Etude rétrospective de 58 patients qui avait un adénocarcinome rectal. Le critère de jugement était la survie. Les paramètres étudiés, le sexe, l’âge, stade tumoral, et les récidives tumorales. Résultats L’âge moyen était de 58 ans. Avec 52% d'hommes contre 48% femmes avec sex-ratio (1,08). Le siège tumoral était: moyen rectum avec 41,37%, 34,48% au bas rectum et dans 24,13% au haut rectum. La classification TNM avec 17,65% au stade I, 18,61% au stade II, 53, 44% au stade III et 7,84% au stade IV. La survie médiane globale était de 40 mois ±2,937 mois. La survie en fonction du stade tumoral, le stade III et IV avait un faible taux de survie (19%) a 3 ans contre le stade I, II avait un taux de survie de (75%) (P = 0,000) (IC 95%). Les patients avec récidives tumorales avaient un taux de survie faible à 3 ans par rapport à ceux n'ayant pas eu de récidive (30,85% Vs 64,30% P = 0,043). Conclusion Dans cette série, l’étude uni varié des différents facteurs pronostiques conditionnant la survie n'a permis de retenir que trois facteurs influençant la survie, à savoir la taille tumorale, le stade, et les récidives tumorales. En analyse multi variée en utilisant le modèle Cox un seul facteur été retenu la récidive tumorale. PMID:27583069

SU-E-T-765: Treatment Planning Comparison of SFUD Proton and 4Ï€ Radiotherapy for Prostate Cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tran, A; Woods, K; Yu, V

2015-06-15

Purpose: Single-Field Uniform Dose (SFUD) proton scanning beams and non-coplanar 4π intensity-modulated radiation therapy (IMRT) represent the most advanced treatment methods based on heavy ion and X-rays, respectively. Here we compare their performance for prostate treatment. Methods: Five prostate patients were planned using 4π radiotherapy and SFUD to an initial dose of 54Gy to a planning target volume (PTV) that encompassed the prostate and seminal vesicles, then a boost prescription dose of 25.2Gy to the prostate for a total dose of 79.2 Gy. 4π plans were created by inversely selecting and optimizing 30 beams from 1162 candidate non-coplanar beams usingmore » a greedy column generation algorithm. The SFUD plans utilized two coplanar, parallel-opposing lateral scanning beams. The SFUD plan PTV was modified to account for range uncertainties while keeping an evaluation PTV identical to that of the X-ray plans for comparison. PTV doses, bladder and rectum dose volumes (V40, V45, V60, V70, V75.6, and V80), R50, and PTV homogeneity index (D95/D5) were evaluated. Results: Compared to SFUD, 4π resulted in 6.8% lower high dose spillage as indicated by R50. Bladder and rectum mean doses were 38.3% and 28.2% lower for SFUD, respectively. However, bladder and rectum volumes receiving >70Gy were 13.1% and 12% greater using proton SFUD. Due to the parallel-opposing beam arrangement, SFUD resulted in greater femoral head (87.8%) and penile bulb doses (43.7%). 4π PTV doses were slightly more homogeneous (HI 0.99 vs. 0.98) than the SFUD dose. Conclusion: Proton is physically advantageous to reduce the irradiated normal volume and mean doses to the rectum and bladder but it is also limited in the beam orientations and entrance dose, which resulted in greater doses to the femoral heads and penile bulb, and larger volumes of rectum and bladder exposed to high dose due to the required robust PTV definition. This project is supported by Varian Medical Systems.« less

SU-E-J-39: Dosimetric Benefit of Implanted Marker-Based CBCT Setup for Definitive Prostatic Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhen, H; Wu, Z; Bluemenfeld, P

Purpose Daily setup for definitive prostatic radiotherapy is challenged by suboptimal visibility of the prostate boundary and daily variation of rectum shape and position. For patients with improved bowel preparation, we conducted a dosimetric comparison between prostate implanted marker (IM)-based daily setup and anterior rectal wall (ARW)-based setup, with the hypothesis that the former leads to adequate target coverage with better rectal sparing. Methods Five IMRT/VMAT prostate cases with implanted markers were selected for analysis. Daily CBCT showed improvement of the rectal volume compared to planning CT. For each patient, the prostate and rectum were contoured on three CBCT imagesmore » (fraction 5/15/25) with subsequent physician review. The CBCTs were then registered to a planning CT using IM-based registration. The deviation of ARW positions from planning CT to CBCT were analyzed at various sup-inf levels (−1.8 cm to 1.8 cm from level of prostate center). To estimate the potential dosimetric impact from ARW-based setup, the treatment plans were recalculated using A-P shifts ranging from −1mm to +6mm. Clinically important rectum DVH values including Dmax, D3cc and Dmean were computed. Results For the studied patients, we observed on average 32% rectum volume reduction from planning CT to CBCT. As a Results, the ARW on average shifts posteriorly by −1mm to +5mm, depending on the sup-inf level of observation, with larger shifts observed at more superior levels. Recalculation shows that when ARW shifts 1mm posteriorly, ARW-based CBCT setup leads to a 1.0%, 4.2%, and 3.2% increase in rectum Dmax, D3cc, and Dmean, respectively, compared to IM-based setup. The dosimetric deviations increase to 4.7%, 25.8% and 24.7% when ARW shifts 6mm posteriorly. No significant prostate-only dose difference was observed. Conclusion For patients with improved bowel preparation, IM-based CBCT setup leads to accurate prostate coverage along with significantly lower rectal dose, compared to ARW-based setup.« less

SU-E-J-221: A Novel Expansion Method for MRI Based Target Delineation in Prostate Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruiz, B; East Carolina University, Greenville, NC; Feng, Y

Purpose: To compare a novel bladder/rectum carveout expansion method on MRI delineated prostate to standard CT and expansion based methods for maintaining prostate coverage while providing superior bladder and rectal sparing. Methods: Ten prostate cases were planned to include four trials: MRI vs CT delineated prostate/proximal seminal vesicles, and each image modality compared to both standard expansions (8mm 3D expansion and 5mm posterior, i.e. ∼8mm) and carveout method expansions (5mm 3D expansion, 4mm posterior for GTV-CTV excluding expansion into bladder/rectum followed by additional 5mm 3D expansion to PTV, i.e. ∼1cm). All trials were planned to total dose 7920 cGy viamore » IMRT. Evaluation and comparison was made using the following criteria: QUANTEC constraints for bladder/rectum including analysis of low dose regions, changes in PTV volume, total control points, and maximum hot spot. Results: ∼8mm MRI expansion consistently produced the most optimal plan with lowest total control points and best bladder/rectum sparing. However, this scheme had the smallest prostate (average 22.9% reduction) and subsequent PTV volume, consistent with prior literature. ∼1cm MRI had an average PTV volume comparable to ∼8mm CT at 3.79% difference. Bladder QUANTEC constraints were on average less for the ∼1cm MRI as compared to the ∼8mm CT and observed as statistically significant with 2.64% reduction in V65. Rectal constraints appeared to follow the same trend. Case-by-case analysis showed variation in rectal V30 with MRI delineated prostate being most favorable regardless of expansion type. ∼1cm MRI and ∼8mm CT had comparable plan quality. Conclusion: MRI delineated prostate with standard expansions had the smallest PTV leading to margins that may be too tight. Bladder/rectum carveout expansion method on MRI delineated prostate was found to be superior to standard CT based methods in terms of bladder and rectal sparing while maintaining prostate coverage. Continued investigation is warranted for further validation.« less

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

PubMed Central

Gay, Hiram A.; Barthold, H. Joseph; O’Meara, Elizabeth; Bosch, Walter R.; El Naqa, Issam; Al-Lozi, Rawan; Rosenthal, Seth A.; Lawton, Colleen; Lee, W. Robert; Sandler, Howard; Zietman, Anthony; Myerson, Robert; Dawson, Laura A.; Willett, Christopher; Kachnic, Lisa A.; Jhingran, Anuja; Portelance, Lorraine; Ryu, Janice; Small, William; Gaffney, David; Viswanathan, Akila N.; Michalski, Jeff M.

2012-01-01

Purpose To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa_R, Adnexa_L, Prostate, SeminalVesc, PenileBulb, Femur_R, and Femur_L. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research. PMID:22483697

Anal fistula with foot extension—Treated by kshara sutra (medicated seton) therapy: A rare case report

PubMed Central

Ramesh, P. Bhat

2013-01-01

INTRODUCTION An ‘anal’ fistula is a track which communicates anal canal or rectum and usually is in continuity with one or more external openings. Distant communication from rectum is rare. It is a challenging disease because of its recurrence especially, with high level and distant communications. Ksharasutra (medicated seton) therapy is being practiced in India with high success rate (recurrence of 3.33%) in the management of complicated anal fistula. PRESENTATION OF CASE A 56 year old man presented with recurrent boils in the left lower limb at different places from thigh to foot. He underwent repeated incision and drainage at different hospitals. Examination revealed sinus with discharge and multiple scars on left lower limb from thigh up to foot. Suspecting anal fistula, MRI was advised which revealed a long cutaneous fistula from rectum to left lower limb. Patient was treated with Ksharasutra therapy. Within 6 months of treatment whole tract was healed completely. DISCUSSION Sushrutha (500BC) was the first to explain the role of surgical excision and use of kshara sutra for the management of anal fistula. Ksharasutra therapy showed least recurrence. Fistula from rectum to foot is of extremely rare variety. Surgical treatment of anal fistula requires hospitalization, regular post-operative care, is associated with a significant risk of recurrence (0.7–26.5%) and a high risk of impaired continence (5–40%). CONCLUSION Rectal fistula communicating till foot may be a very rare presentation in proctology practice. Kshara sutra treatment was useful in treating this condition, with minimal surgical intervention with no recurrence. PMID:23702360

Prospective clinical validation of independent DVH prediction for plan QA in automatic treatment planning for prostate cancer patients.

PubMed

Wang, Yibing; Heijmen, Ben J M; Petit, Steven F

2017-12-01

To prospectively investigate the use of an independent DVH prediction tool to detect outliers in the quality of fully automatically generated treatment plans for prostate cancer patients. A plan QA tool was developed to predict rectum, anus and bladder DVHs, based on overlap volume histograms and principal component analysis (PCA). The tool was trained with 22 automatically generated, clinical plans, and independently validated with 21 plans. Its use was prospectively investigated for 50 new plans by replanning in case of detected outliers. For rectum D mean , V 65Gy , V 75Gy , anus D mean , and bladder D mean , the difference between predicted and achieved was within 0.4 Gy or 0.3% (SD within 1.8 Gy or 1.3%). Thirteen detected outliers were re-planned, leading to moderate but statistically significant improvements (mean, max): rectum D mean (1.3 Gy, 3.4 Gy), V 65Gy (2.7%, 4.2%), anus D mean (1.6 Gy, 6.9 Gy), and bladder D mean (1.5 Gy, 5.1 Gy). The rectum V 75Gy of the new plans slightly increased (0.2%, p = 0.087). A high accuracy DVH prediction tool was developed and used for independent QA of automatically generated plans. In 28% of plans, minor dosimetric deviations were observed that could be improved by plan adjustments. Larger gains are expected for manually generated plans. Copyright © 2017 Elsevier B.V. All rights reserved.

Intramural distribution of regulatory peptides in the sigmoid-recto-anal region of the human gut.

PubMed

Ferri, G L; Adrian, T E; Allen, J M; Soimero, L; Cancellieri, A; Yeats, J C; Blank, M; Polak, J M; Bloom, S R

1988-06-01

The distribution of regulatory peptides was studied in the separated mucosa, submucosa and muscularis externa taken at 10 sampling sites encompassing the whole human sigmoid colon (five sites), rectum (two sites), and anal canal (three sites). Consistently high concentrations of VIP were measured in the muscle layer at most sites (proximal sigmoid: 286 (16) pmol/g, upper rectum: 269 (17), a moderate decrease being found in the distal smooth sphincter (151 (30) pmol/g). Values are expressed as mean (SE). Conversely, substance P concentrations showed an obvious decline in the recto-anal muscle (mid sigmoid: 19 (2.0) pmol/g, distal rectum: 7.1 (1.3), upper anal canal: 1.6 (0.6)). Somatostatin was mainly present in the sigmoid mucosa and submucosa (37 (9.3) and 15 (3.5) pmol/g, respectively) and showed low, but consistent concentrations in the muscle (mid sigmoid: 2.2 (0.7) pmol/g, upper anal canal: 1.5 (0.8]. Starting in the distal sigmoid colon, a distinct peak of tissue NPY was revealed, which was most striking in the muscle (of mid sigmoid: 16 (3.9) pmol/g, upper rectum: 47 (7.8), anal sphincter: 58 (14)). Peptide YY was confined to the mucosa and showed an earlier peak (upper sigmoid: 709 (186) pmol/g, mid-distal sigmoid: 1965 (484)). A clear differential distribution of regulatory peptides was thus shown in the region studied. A possible role is suggested for NPY and VIP containing nerves in the effector control of the human internal anal sphincter.

Intramural distribution of regulatory peptides in the sigmoid-recto-anal region of the human gut.

PubMed Central

Ferri, G L; Adrian, T E; Allen, J M; Soimero, L; Cancellieri, A; Yeats, J C; Blank, M; Polak, J M; Bloom, S R

1988-01-01

The distribution of regulatory peptides was studied in the separated mucosa, submucosa and muscularis externa taken at 10 sampling sites encompassing the whole human sigmoid colon (five sites), rectum (two sites), and anal canal (three sites). Consistently high concentrations of VIP were measured in the muscle layer at most sites (proximal sigmoid: 286 (16) pmol/g, upper rectum: 269 (17), a moderate decrease being found in the distal smooth sphincter (151 (30) pmol/g). Values are expressed as mean (SE). Conversely, substance P concentrations showed an obvious decline in the recto-anal muscle (mid sigmoid: 19 (2.0) pmol/g, distal rectum: 7.1 (1.3), upper anal canal: 1.6 (0.6)). Somatostatin was mainly present in the sigmoid mucosa and submucosa (37 (9.3) and 15 (3.5) pmol/g, respectively) and showed low, but consistent concentrations in the muscle (mid sigmoid: 2.2 (0.7) pmol/g, upper anal canal: 1.5 (0.8]. Starting in the distal sigmoid colon, a distinct peak of tissue NPY was revealed, which was most striking in the muscle (of mid sigmoid: 16 (3.9) pmol/g, upper rectum: 47 (7.8), anal sphincter: 58 (14)). Peptide YY was confined to the mucosa and showed an earlier peak (upper sigmoid: 709 (186) pmol/g, mid-distal sigmoid: 1965 (484)). A clear differential distribution of regulatory peptides was thus shown in the region studied. A possible role is suggested for NPY and VIP containing nerves in the effector control of the human internal anal sphincter. PMID:2454876

TRANSITIONAL CELL CANCER OF THE ANUS AND RECTUM

PubMed Central

Grodsky, Lewis

1961-01-01

A study was made of all cases of transitional cell cancer of the anus or rectum in the records of the University of California Medical Center, San Francisco. None was listed until 1945, then an additional seven between 1954 and 1960. During the latter period there were 192 cases of adenocarcinoma of the rectum, six cases of squamous cell or epidermoid rectal cancer and 12 cases of squamous cell cancer of the anus. Distinctive and highly malignant anal and rectal epithelial tumors will occasionally arise at or near the anorectal junction from inconstant embryologic entodermal cloacal vestiges. These atypical nonkeratinizing lesions are very similar microscopically to transitional cell tumors found in the cloacogenic portions of the lower genitourinary tract. Review of the literature indicates that the prognosis of cloacogenic anal and rectal lesions appears to be relatively graver than that for the more common adenocarcinomas and keratinizing squamous cell epitheliomas. Early diagnosis and prompt, radical excision seem to offer the only hope for survival. ImagesFigure 1.Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:13902070

Reducing rectal injury in men receiving prostate cancer radiation therapy: current perspectives

PubMed Central

Serrano, Nicholas A; Kalman, Noah S; Anscher, Mitchell S

2017-01-01

Dose escalation is now the standard of care for the treatment of prostate cancer with radiation therapy. However, the rectum tends to be the dose-limiting structure when treating prostate cancer, given its close proximity. Early and late toxicities can occur when the rectum receives large doses of radiation therapy. New technologies allow for prevention of these toxicities. In this review, we examine the evidence that supports various dose constraints employed to prevent these rectal injuries from occurring. We also examine the use of intensity-modulated radiation therapy and how this compares to older radiation therapy techniques that allow for further sparing of the rectum during a radiation therapy course. We then review the literature on endorectal balloons and the effects of their daily use throughout a radiation therapy course. Tissue spacers are now being investigated in greater detail; these devices are injected into the rectoprostatic fascia to physically increase the distance between the prostate and the anterior rectal wall. Last, we review the use of systemic drugs, specifically statin medications and antihypertensives, as well as their impact on rectal toxicity. PMID:28814898

Comparison of Rectal and Esophageal Sensitivity in Women With Functional Heartburn.

PubMed

Freede, Margaret; Leasure, A Renee; Proskin, Howard M; Hatch, Daniel; Edwards, Karethy; Pascucci, MaryAnn; Smith, Patsy R

2016-01-01

This study tested the primary hypothesis that there is a correlation of maximum pain threshold (MPT) in the esophagus and rectum in persons with functional heartburn. Secondary aims evaluated correlations with initial perception threshold (IPT) and pain threshold (PT). This study explored objective sensory endpoints of IPT, PT, and MPT in the esophagus and rectum of 14 females with functional heartburn to determine whether visceral hypersensitivity is generalized or organ-specific. Data on volume and pressure measurements at IPT, PT, and MPT with esophageal and rectal barostat distention were collected. The relationship of sensation and pain to volume, pressure, and compliance was analyzed. Esophageal and rectal IPT balloon volume scores were highly and significantly correlated (r = .61, p = .02). Esophageal and rectal PT balloon volume scores were highly and significantly correlated (r = .6, p = .02). Esophageal and rectal MPT balloon volume scores were not correlated (r = .35, p = .26). The correlation of visceral sensitivity in the esophagus and rectum in persons with functional heartburn supports the hypothesis that visceral sensory changes in functional gastrointestinal disorders are not organ specific.

Neoplastic sigmoid-uterine fistula. An exceptional complication of large intestine cancer

PubMed Central

ZANGHÌ, G.; LEANZA, V.; VECCHIO, R.; D’AGATI, A.; CORDOVA, S.; RINZIVILLO, N.M.; LODATO, M.; LEANZA, G.

2017-01-01

Neoplastic sigmoid-uterine fistula is an extremely rare condition because the uterus is a thick and muscular organ. A 74-year-old woman was admitted to the First Aid Station suffering from abdominal pain and foul smelling vaginal discharge. Gynaecological examination showed fecal drainage from the cervical orifice, while the uterus was regular in size but very firm and painful. Ovaries and fallopian tubes were not palpable owing to abdominal tenderness. Ultrasounds reveled inhomogeneous thickening of uterine cavity, without detecting fistula. Contrast Medium CT (CMCT) showed Douglas’ recto-uterine pouch occluded. The sigmoid wall was very thin exception a site where a fistula was suspected. At the surgery severe adhesions of the sigma-rectum with the posterior uterine wall were observed. After adhesiolysis, 18 cm colon-sigma-rectum was removed. Total hysterectomy with salpingooophorectomy was performed. Lymphadenectomy ended the procedure. Anatomical specimen confirmed sigmoid-uterine fistula. At histology a mildly differentiated adenocarcinoma of sigma-rectum was shown. Postoperative course was uneventful. Such a case of neoplastic sigmoid-uterine fistula has not been reported so far. PMID:28460202

Rectal shaving for deep endometriosis infiltrating the rectum: a 5-year continuous retrospective series.

PubMed

Roman, Horace; Moatassim-Drissa, Salwa; Marty, Noemie; Milles, Mathilde; Vallée, Aurélie; Desnyder, Eulalie; Stochino Loi, Emanuela; Abo, Carole

2016-11-01

To report postoperative outcomes after rectal shaving for deep endometriosis infiltrating the rectum. Retrospective study using data prospectively recorded in the CIRENDO database. University tertiary referral center. One hundred and twenty-two consecutive patients whose follow-up observation ranged from 1 to 6 years. Rectal shaving performed using ultrasound scalpel or scissors and plasma energy in 68 and 54 women, respectively. Postoperative digestive function assessed using standardized gastrointestinal questionnaires: the Gastrointestinal Quality of Life Index (GIQLI) and the Knowles-Eccersley-Scott-Symptom Questionnaire (KESS). Nodules were between 1 and 3 cm, <1 cm, and >3 cm in diameter, in 73.7%, 11.5%, and 14.8% of cases, respectively. They were located on the middle (49.2%) and upper rectum (50.8%). Clavien-Dindo 3a, 3b, 4a, and 4b complications occurred in 0.8%, 5.7%, 1.6%, and 0.8% of cases, respectively. Excepting two rectal fistulas (1.6%), the majority of complications were not related to rectal shaving itself. Gastrointestinal scores revealed statistically significant improvement in digestive function and pelvic pain at 1 and 3 years after rectal shaving, but not constipation. Rectal recurrences occurred in 4% of patients, 2.4% of whom had segmental resection, 0.8% shaving, and 0.8% disc excision. Three years postoperatively, the pregnancy rate was 65.4% among patients with pregnancy intention, 59% of whom conceived spontaneously. Our data suggest that rectal shaving is a valuable treatment for deep endometriosis infiltrating the rectum, providing a low rate of postoperative complications, good improvement in digestive function, and satisfactory fertility outcomes. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Effectiveness of Educational Intervention on the Congruence of Prostate and Rectal Contouring as Compared With a Gold Standard in Three-Dimensional Radiotherapy for Prostate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szumacher, Ewa, E-mail: Ewa.Szumacher@sunnybrook.c; Harnett, Nicole; Warner, Saar

Purpose: To examine effects of a teaching intervention on precise delineation of the prostate and rectum during planning of three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Methods and Materials: A pretest, posttest, randomized controlled group design was used. During pretest all participants contoured prostate and rectum on planning CT. Afterward, they participated in two types of workshops. The experimental group engaged in an interactive teaching session focused on prostate and rectum MR anatomy compared with CT anatomy. The control group focused on 3D-CRT planning without mention of prostate or rectal contouring. The experimental group practiced on fused MR-CT images, whereasmore » the control group practiced on CT images. All participants completed the posttest. Results: Thirty-one trainees (12 male, 19 female) were randomly assigned to two groups, 17 in the experimental arm, and 14 in the control group. Seventeen felt familiar or very familiar with pelvic organ contouring, 12 somewhat, and 2 had never done it. Thirteen felt confident with organ contouring, 13 somewhat, and 5 not confident. The demographics and composition of groups were analyzed with chi{sup 2} and repeated-measures analysis of variance with the two groups (experimental or control) and two tests (pre- or posttest) as factors. Satisfaction with the course and long-term effects of the course on practice were assessed with immediate and delayed surveys. All performance variables showed a similar pattern of results. Conclusions: The training sessions improved the technical performance similarly in both groups. Participants were satisfied with the course content, and the delayed survey reflected that cognitively participants felt more confident with prostate and rectum contouring and would investigate opportunities to learn more about organ contouring.« less

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gay, Hiram A., E-mail: hgay@radonc.wustl.edu; Barthold, H. Joseph; Beth Israel Deaconess Medical Center, Boston, MA

2012-07-01

Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The followingmore » were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.« less

Concept design and simulation study on a "phantom" anvil for circular stapler.

PubMed

Rulli, Francesco; Kartheuser, Alex; Amirhassankhani, Sasan; Mourad, Michel; Stefani, Mario; de Ferrá Aureli, Andrés; Sileri, Pierpaolo; Valentini, Pier Paolo

2015-04-01

Complications and challenges arising from the intraoperative double-stapling technique are seldom reported in colorectal surgery literature. Partial or full-thickness rectal injuries can occur during the introduction and the advancement of the circular stapler along the upper rectum. The aim of this study is to address some of these issues by designing and optimizing a "phantom" anvil manufactured to overcome difficulties throughout the rectal introduction and advancement of the circular stapler for the treatment of benign and malignant colon disease. The design of the "phantom" anvil has been performed using computer-aided modeling techniques, finite element investigations, and 2 essential keynotes in mind. The first one is the internal shape of the anvil, which is used for the connection to the gun. The second is the shape of the cap, which makes possible the insertion of the gun through the rectum. The "phantom" anvil has 2 functional requirements, which have been taken into account. The design has been optimized to avoid colorectal injuries, neoplastic dissemination (ie, mechanical seeding) and to reduce the fecal contamination. Numerical simulations show that a right combination of both top and bottom fillet radii of the shape of the anvil can reduce the stress for the considered anatomic configuration of >90%. Both the fillet radii at the top and the bottom of the device influence the local stress of the colon rectum. A dismountable device, which is used only for the insertion and advancement of the stapler, allows a dedicated design of its shape, keeping the remainder of the stapler unmodified. Computer-aided simulations are useful to perform numerical investigations to optimize the design of this auxiliary part for both the safety of the patient and the ease of the stapler advancement through the rectum.

Anal fistula with foot extension-Treated by kshara sutra (medicated seton) therapy: A rare case report.

PubMed

Ramesh, P Bhat

2013-01-01

An 'anal' fistula is a track which communicates anal canal or rectum and usually is in continuity with one or more external openings. Distant communication from rectum is rare. It is a challenging disease because of its recurrence especially, with high level and distant communications. Ksharasutra (medicated seton) therapy is being practiced in India with high success rate (recurrence of 3.33%) in the management of complicated anal fistula. A 56 year old man presented with recurrent boils in the left lower limb at different places from thigh to foot. He underwent repeated incision and drainage at different hospitals. Examination revealed sinus with discharge and multiple scars on left lower limb from thigh up to foot. Suspecting anal fistula, MRI was advised which revealed a long cutaneous fistula from rectum to left lower limb. Patient was treated with Ksharasutra therapy. Within 6 months of treatment whole tract was healed completely. Sushrutha (500BC) was the first to explain the role of surgical excision and use of kshara sutra for the management of anal fistula. Ksharasutra therapy showed least recurrence. Fistula from rectum to foot is of extremely rare variety. Surgical treatment of anal fistula requires hospitalization, regular post-operative care, is associated with a significant risk of recurrence (0.7-26.5%) and a high risk of impaired continence (5-40%). Rectal fistula communicating till foot may be a very rare presentation in proctology practice. Kshara sutra treatment was useful in treating this condition, with minimal surgical intervention with no recurrence. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Locally-constrained Boundary Regression for Segmentation of Prostate and Rectum in the Planning CT Images

PubMed Central

Shao, Yeqin; Gao, Yaozong; Wang, Qian; Yang, Xin; Shen, Dinggang

2015-01-01

Automatic and accurate segmentation of the prostate and rectum in planning CT images is a challenging task due to low image contrast, unpredictable organ (relative) position, and uncertain existence of bowel gas across different patients. Recently, regression forest was adopted for organ deformable segmentation on 2D medical images by training one landmark detector for each point on the shape model. However, it seems impractical for regression forest to guide 3D deformable segmentation as a landmark detector, due to large number of vertices in the 3D shape model as well as the difficulty in building accurate 3D vertex correspondence for each landmark detector. In this paper, we propose a novel boundary detection method by exploiting the power of regression forest for prostate and rectum segmentation. The contributions of this paper are as follows: 1) we introduce regression forest as a local boundary regressor to vote the entire boundary of a target organ, which avoids training a large number of landmark detectors and building an accurate 3D vertex correspondence for each landmark detector; 2) an auto-context model is integrated with regression forest to improve the accuracy of the boundary regression; 3) we further combine a deformable segmentation method with the proposed local boundary regressor for the final organ segmentation by integrating organ shape priors. Our method is evaluated on a planning CT image dataset with 70 images from 70 different patients. The experimental results show that our proposed boundary regression method outperforms the conventional boundary classification method in guiding the deformable model for prostate and rectum segmentations. Compared with other state-of-the-art methods, our method also shows a competitive performance. PMID:26439938

Quantitative distribution of radiolabeled 5-aminosalicylic acid enemas in patients with left-sided ulcerative colitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vitti, R.A.; Meyers, F.; Knight, L.C.

1989-11-01

Rectally administered suspensions of 5-aminosalicylic acid (5-ASA) are topically effective in treating left-sided ulcerative colitis. The extent to which the contents of these enemas are distributed to inflamed mucosal linings has not previously been determined. This study was undertaken to validate a technique for labeling 5-ASA with 99mTc and to quantitate the distribution of (99mTc)5-ASA in eight patients with left-sided ulcerative colitis. Eight patients underwent three colonic scintigraphic exams within five days, receiving a 60-ml radiolabeled 5-ASA enema into the unprepared rectum for each study, with sequential anterior abdominal images obtained for 4 hr. Activity within the rectum, sigmoid, descending,more » transverse, and ascending colon was quantitated. Over 50% of the labeled enema had advanced beyond the rectum in five of eight patients and in six of eight patients by 30 min and 60 min, respectively. The distribution of (99mTc)5-ASA was quantitatively reproducible when repeated in the same patient on different days, despite apparent visual differences. By 2 hr, the amount of the enema present within the rectum decreased significantly (P less than 0.05) compared to the initial distribution. The amount of enema present within the descending colon was increased significantly at 0.5 hr (P less than 0.05) and at 2 hr (P less than 0.01). There were no significant changes in the distribution from initial values for the sigmoid, transverse, or ascending colon at any time. In each of these cases the spread of the enema to or beyond the extent of disease was documented. In patients with left-sided ulcerative colitis, small volume (99mTc)5-ASA enemas reliably reach the area of inflammation.« less

Colostomy and drainage for civilian rectal injuries: is that all?

PubMed Central

Burch, J M; Feliciano, D V; Mattox, K L

1989-01-01

One hundred consecutive patients with injuries to the extraperitoneal rectum were treated over a ten-year period at an urban trauma center. The mechanisms of injury included firearms in 82 patients, stab wounds in 3 patients, a variety of other penetrating injuries in 10 patients, and in 5 patients the injuries resulted from blunt trauma. Treatment of the rectal injury was determined by the bias of the operating surgeon, the condition of the patient, and the magnitude of the rectal injury. Proximal loop colostomies were performed in 44 patients, diverting colostomies in 51 patients, Hartmann's procedure in 4 patients, and an abdominoperineal resection in 1 patient. Extraperitoneal rectal perforations were closed in 21 patients and the rectum was irrigated free of feces in 46 patients. Transperineal, presacral drainage was used in 93 patients. Infectious complications potentially related to the management of the rectal wound occurred in 11 patients (11%) and included abdominal or pelvic abscesses (4 patients), wound infections (6 patients), rectocutaneous fistulas (3 patients), and missile tract infections (2 patients). Four patients (4%) died as a result of their injuries. Of the therapeutic options available, statistical analysis revealed that only the failure to drain the presacral space increased the likelihood of infectious complications (p = 0.03); however, as it could not be determined with certainty that the use of, or failure to use, any particular therapeutic option had an effect on the risk of death. It is concluded that colostomy and drainage are the foundations of the successful treatment of civilian injuries to the extraperitoneal rectum. The use of adjuncts such as diverting colostomies, repair of the rectal wound, and irrigation of the rectum has little effect on mortality and morbidity. PMID:2705824

Electrophysiological characterization of human rectal afferents

PubMed Central

Ng, Kheng-Seong; Brookes, Simon J.; Montes-Adrian, Noemi A.; Mahns, David A.

2016-01-01

It is presumed that extrinsic afferent nerves link the rectum to the central nervous system. However, the anatomical/functional existence of such nerves has never previously been demonstrated in humans. Therefore, we aimed to identify and make electrophysiological recordings in vitro from extrinsic afferents, comparing human rectum to colon. Sections of normal rectum and colon were procured from anterior resection and right hemicolectomy specimens, respectively. Sections were pinned and extrinsic nerves dissected. Extracellular visceral afferent nerve activity was recorded. Neuronal responses to chemical [capsaicin and “inflammatory soup” (IS)] and mechanical (Von Frey probing) stimuli were recorded and quantified as peak firing rate (range) in 1-s intervals. Twenty-eight separate nerve trunks from eight rectums were studied. Of these, spontaneous multiunit afferent activity was recorded in 24 nerves. Peak firing rates increased significantly following capsaicin [median 6 (range 3–25) spikes/s vs. 2 (1–4), P < 0.001] and IS [median 5 (range 2–18) spikes/s vs. 2 (1–4), P < 0.001]. Mechanosensitive “hot spots” were identified in 16 nerves [median threshold 2.0 g (range 1.4–6.0 g)]. In eight of these, the threshold decreased after IS [1.0 g (0.4–1.4 g)]. By comparison, spontaneous activity was recorded in only 3/30 nerves studied from 10 colons, and only one hot spot (threshold 60 g) was identified. This study confirms the anatomical/functional existence of extrinsic rectal afferent nerves and characterizes their chemo- and mechanosensitivity for the first time in humans. They have different electrophysiological properties to colonic afferents and warrant further investigation in disease states. PMID:27789454

En bloc endoscopic submucosal dissection of a 14-cm laterally spreading adenoma of the rectum with involvement to the anal canal: expanding the frontiers of endoscopic surgery (with video).

PubMed

Antillon, Mainor R; Bartalos, Christopher R; Miller, Marc L; Diaz-Arias, Alberto A; Ibdah, Jamal A; Marshall, John B

2008-02-01

Endoscopic submucosal dissection (ESD) was recently developed in Japan for en bloc removal of laterally spreading tumors (LSTs). Although initially used for gastric tumors, ESD has now been applied to lesions elsewhere in the gut. Recent reports from Japan included removal of colorectal lesions up to 10 cm. To show the feasibility of ESD to remove en bloc, very large LSTs of the rectum, even when there is involvement to the dentate line. Case report. The procedure was performed at an American GI unit. The patient was admitted to the hospital after the procedure for observation. A 53-year-old patient, with a 14-cm tubulovillous adenoma of the rectum, which, at its maximal extent, involved two thirds of the circumference of the rectum. The tumor extended distally to the dentate line. En bloc submucosal dissection with a conventional needle-knife to remove the neoplasm. Completeness of en bloc removal of the tumor and subsequent follow-up endoscopy that showed no residual neoplasm. The tumor was able to be removed en bloc by ESD. The distal margin included squamous mucosa. At a 2.5-week endoscopic follow-up, a 3-mm focus of residual polyp was seen and removed. At the time of the last follow-up, there was complete healing of the wound and no residual neoplasm. Single case. This case demonstrated the feasibility of using ESD to remove large laterally spreading rectal tumors, including when there was involvement to the dentate line (and the dissection line must include squamous mucosa of the anal canal). ESD is a promising alternative to conventional surgical techniques; however, additional published experience is needed.

Ovarian mature cystic teratoma with fistula formation into the rectum: a case report.

PubMed

Kizaki, Yuichiro; Nagai, Tomonori; Ohara, Ken; Gomi, Yosuke; Akahori, Taichi; Ono, Yoshihisa; Matsunaga, Shigetaka; Takai, Yasushi; Saito, Masahiro; Baba, Kazunori; Seki, Hiroyuki

2016-01-01

While ovarian mature cystic teratomas are benign ovarian germ-cell tumors and the most common type of all ovarian tumors, the formation of fistulas into surrounding organs such as the bladder and the intestinal tract is extremely rare. This report documents a case of ovarian mature cystic teratoma with a rectal fistula, thought to be caused by local inflammation. A pelvic mass was diagnosed as an ovarian mature cystic teratoma of approximately 10 cm in diameter on transvaginal ultrasound and magnetic resonance examinations. Endoscopic examination of the lower gastrointestinal tract to investigate diarrhea revealed an ulcerative lesion with hair in the rectal wall adjacent to the ovarian cyst, and formation of a fistula from the ovarian teratoma into the rectum was suspected. Laparotomy revealed extensive inflammatory adhesions between a left ovarian tumor and the rectum. Left salpingo-oophorectomy and upper anterior resection of the rectum were performed. The final pathological diagnosis was ovarian mature cystic teratoma with no malignant findings, together with severe rectal inflammation and fistula formation with no structural disorders such as diverticulitis of the colon or malignant signs. The formation of fistulas and invasion into the neighboring organs are extremely rare complications for ovarian mature cystic teratomas. The invasion of malignant cells into neighboring organs due to malignant transformation of the tumor is reported as the cause of fistula formation into the neighboring organs. A review of 17 cases including the present case revealed that fistula formation due to malignant transformation comprised only 4 cases (23.5 %), with inflammation as the actual cause in the majority of cases (13 cases, 76.5 %). Although malignancy is the first consideration when fistula formation is observed between ovarian tumors and surrounding organs, in mature cystic teratoma, local inflammation is more likely than malignant transformation.

Pelvic Myxoid Leiomyoma Mass between Vagina and Rectum.

PubMed

AlShalabi, Omar; Alahmar, Fadi Obaied; Aljasem, Hazem; Alsaid, Bayan; AlShalabi, Abdulghani

2016-01-01

Leiomyomas are the most common pelvic tumors in women. About 20-30% of women older than 35 are affected. Rare conditions of leiomyomas have extrauterine locations. Myxoid degeneration is a rare type of leiomyoma degeneration. We report a case of solid-cystic myxoid leiomyoma in a 53-year-old woman complained of constipation, urinary hesitation, and malodorous vaginal discharge with palpable 17 × 12 cm mass between vagina and rectum. Regarding the inferior location of the mass, a perineal approach was used to enucleate it. This rare location has not been mentioned before. The woman was finally diagnosed by pathologists which was myxoid leiomyoma.

Rectal lymphoma in 11 dogs: a retrospective study.

PubMed

Van den Steen, N; Berlato, D; Polton, G; Dobson, J; Stewart, J; Maglennon, G; Hayes, A M; Murphy, S

2012-10-01

To retrospectively evaluate the clinical behaviour and immunophenotype of lymphoma of the rectum in dogs. Eleven dogs diagnosed with lymphoma of the rectum on histopathology were retrospectively reviewed. Immunohistochemistry with CD3 and CD79a antibodies was performed at diagnosis or retrospectively. Treatment protocol varied with six dogs undergoing surgery and adjuvant chemotherapy, two received chemotherapy after only incisional biopsy, one had surgical resection only, one was treated symptomatically and one dog was not treated. Chemotherapy treatment consisted of either a -low-dose COP (cyclophosphamide - prednisolone - vincristine) protocol (four dogs) or a six-week CHOP-based (cyclophosphamide - vincristine - -prednisolone - anthracycline) protocol (four dogs). Dogs that received chemotherapy lived significantly longer than dogs that did not receive chemotherapy (2352 versus 70 days). Median survival time was not reached, and there was an overall mean survival time of 1697 days. Immunohistochemistry was performed in 10 of 11 samples, and was consistent with B-cell -lymphoma in all cases. Canine lymphoma of the rectum is associated with a favourable prognosis. Immunohistochemical evaluation of these lesions was consistent with B-cell lymphoma in all cases in which it was examined. © 2012 British Small Animal Veterinary Association.

Preliminary Study of a Novel Puborectalis-Like Artificial Anal Sphincter.

PubMed

Jin, Wentian; Yan, Guozheng; Wu, Hao; Lu, Shan; Zhou, Zerun

2017-09-01

Artificial anal sphincter (AAS) is an in situ implanted device that acts as a treatment for fecal incontinence regardless of etiology by augmenting the incompetent sphincteric structures. However, AAS is impeded from becoming a valid therapy by its high rate of ischemic complication and malfunction. This article presents an original puborectalis-like artificial anal sphincter (PAAS) that features a low risk of ischemia necrosis and rectal perception remodeling. The device retains continence by reproducing the action, including the pulling and angulating the rectum, of the puborectalis muscle, which forms the anorectal angle and reduces the required clamping pressure. Three rectal pressure sensors were embedded to maintain the pressure exerted on the rectal wall in a safe range and to monitor the distention of the rectum. A series of in vitro studies were conducted with a porcine rectum, and this PAAS prototype manifested the ability of maintaining continence with a clamping pressure considerably lower than that required by other AAS devices. The pressure sensors exhibit good linearity, and the function of rectal perception remodeling has also revealed high reliability with a success rate of 93.3%. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Lymphogranuloma venereum as a cause of rectal strictures.

PubMed Central

Papagrigoriadis, S.; Rennie, J. A.

1998-01-01

Rectal strictures are uncommon in young patients without a history of malignancy, inflammatory bowel disease or previous surgery. Lymphogranuloma venereum of the rectum has been described as a rare cause of rectal strictures in the western world, mainly in homosexual men and in blacks. It presents with nonspecific symptoms, rectal ulcer, proctitis, anal fissures, abscesses and rectal strictures. Clinical and endoscopic findings as well as histology resemble Crohn's disease, which may be misdiagnosed. Serology is often positive for Chlamydia trachomatis but negative serology is not uncommon. We present two young black women who suffered from chronic diarrhoea, abdominal pain and weight loss. There was no previous history and investigations showed in both cases a long rectal stricture. Serology was positive in one patient. They were treated with erythromycin and azithromycin and they both underwent an anterior resection of the rectum. Postoperative histology confirmed the presence of lymphogranuloma venereum of the rectum. We conclude that rectal lymphogranuloma venereum is a rare cause of rectal strictures but surgeons should be aware of its existence and include it in the differential diagnosis of unexplained strictures in high-risk patients. Images Figure 1 Figure 2 PMID:9640444

Dosimetry of intracavitary placements for uterine and cervical carcinoma: results of orthogonal film, TLD, and CT-assisted techniques.

PubMed

Kapp, K S; Stuecklschweiger, G F; Kapp, D S; Hackl, A G

1992-07-01

A total of 720 192Ir high-dose-rate (HDR) applications in 331 patients with gynecological tumors were analyzed to evaluate the dose to normal tissues from brachytherapy. Based on the calculations of bladder base, bladder neck, and rectal doses derived from orthogonal films the planned tumor dose or fractionation was altered in 20.4% of intracavitary placements (ICP) for cervix carcinoma and 9.2% of ICP for treatment of the vaginal vault. In 13.8% of intracervical and 8.1% of intravaginal treatments calculated doses to both the bladder and rectum were greater than or equal to 140% of the initially planned dose fraction. Doses at the bladder base were significantly higher than at the bladder neck (p less than 0.001). In 17.5% of ICP the dose to the bladder base was at least twice as high as to the bladder neck. The ratio of bladder base dose to the bladder neck was 1.5 (+/- 1.19 SD) for intracervical and 1.46 (+/- 1.14 SD) for intravaginal applications. The comparison of calculated doses from orthogonal films with in-vivo readings showed a good correlation of rectal doses with a correlation coefficient factor of 0.9556. CT-assisted dosimetry, however, revealed that the maximum doses to bladder and rectum were generally higher than those obtained from films with ratios of 1-1.7 (average: 1.44) for the bladder neck, 1-5.4 (average: 2.42) for the bladder base, and 1.1-2.7 (average: 1.37) for the rectum. When doses to the specified reference points of bladder neck and rectum from orthogonal film dosimetry were compared with the corresponding points on CT scans, similar values were obtained for both methods with a maximum deviation of +/- 10%. Despite the determination of multiple reference points our study revealed that this information was inadequate to predict doses to the entire rectum and bladder. If conventional methods are used for dosimetry it is recommended that doses to the bladder base should be routinely calculated, since single point measurements at the bladder neck seriously underestimate the dose to the bladder. Also the rectal dose should be determined at several points over the length of the implant due to the wide range of anatomic variations possible.

Technical Note: System for evaluating local hypothermia as a radioprotector of the rectum in a small animal model.

PubMed

Hrycushko, Brian A; Bing, Chenchen; Futch, Cecil; Wodzak, Michelle; Stojadinovic, Strahinja; Medin, Paul M; Chopra, Rajiv

2017-08-01

The protective effects of induced or even accidental hypothermia on the human body are widespread with several medical uses currently under active research. In vitro experiments using human cell lines have shown hypothermia provides a radioprotective effect that becomes more pronounced at large, single-fraction doses common to stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS) treatments. This work describes the development of a system to evaluate local hypothermia for a radioprotective effect of the rat rectum during a large dose of radiation relevant to prostate SBRT. This includes the evaluation of a 3D-printed small animal rectal cooling device and the integration with a small animal irradiator. A 3-cm long, dual-lumen rectal temperature control apparatus (RTCA) was designed in SOLIDWORKS CAD for 3D printing. The RTCA was capable of recirculating flow in a device small enough for insertion into the rat rectum, with a metal support rod for strength as well as visibility during radiation treatment planning. The outer walls of the RTCA comprised of thin heat shrink plastic, achieving efficient heat transfer into adjacent tissues. Following leak-proof testing, fiber optic temperature probes were used to evaluate the temperature over time when placed adjacent to the cooling device within the rat rectum. MRI thermometry characterized the relative temperature distribution in concentric ROIs surrounding the probe. Integration with an image-guided small animal irradiator and associated treatment planning system included evaluation for imaging artifacts and effect of brass tubing on dose calculation. The rectal temperature adjacent to the cooling device decreased from body temperature to 15°C within 10-20 min from device insertion and was maintained at 15 ± 3°C during active cooling for the evaluated time of one hour. MR thermometry revealed a steep temperature gradient with increasing distance from the cooling device with the desired temperature range maintained within the surrounding few millimeters. A 3D-printed rectal cooling device was fabricated for the purpose of inducing local hypothermia in the rat rectum. The RTCA was simply integrated with an image-guided small animal irradiator and Monte Carlo-based treatment planning system to facilitate an in vivo investigation of the radioprotective effect of hypothermia for late rectal toxicity following a single large dose of radiation. © 2017 American Association of Physicists in Medicine.

The importance of prostate bed tilt during postprostatectomy intensity-modulated radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, Linda J., E-mail: Linda.Bell1@health.nsw.gov.au; Faculty of Health Sciences, University of Sydney, Lidcombe, New South Wales; Cox, Jennifer

2014-10-01

Variations in rectal and bladder filling can create a tilt of the prostate bed, which generates the potential for a geographic miss during postprostatectomy radiotherapy. The aim of this study is to assess the effect that bladder and rectum filling has on planning target volume angle, to determine a method to assess prostate bed tilt leading to potential geographic miss, and to discuss possible implementation issues. The cone-beam computed tomography images (n = 377) of 40 patients who received postprostatectomy radiotherapy with intensity-modulated radiotherapy were reviewed. The amount of tilt in the prostate bed was defined as the angle changemore » between 2 surgical clips, one in the upper prostate bed and another in the lower. A potential geographic miss was defined as movement of any clip of more than 1 cm in any direction or 0.5 cm posteriorly when aligned to bone anatomy. Variations in bladder and rectum size were correlated with the degree of prostate bed tilt, and the rate of potential geographic miss was determined. A possible clinical use of prostate bed tilt was then assessed for different imaging techniques. A tilt of more than 10° was seen in 20.2% of images, which resulted in a 57.9% geographic miss rate of the superior clip. When tilt remained within 10°, there was only a 9% rate of geographic miss. Potential geographic miss of the inferior surgical clip was rare, occurring in only 1.9% of all images reviewed. The most common occurrence when the prostate bed tilt increased by more than 10° was a smaller bladder and larger rectum (6.4% of all images). The most common occurrence when the prostate bed tilt decreased by more than 10° was a larger bladder and smaller rectum (1.3% of all images). Significant prostate bed tilt (>± 10°) occurred in more than 20% of images, creating a 58% rate of geographic miss. Greatest prostate bed tilt occurred when the bladder size increased or reduced by more than 2 cm or the superior rectum size increased by more than 1.5 cm or reduced by more than 1 cm from the planned size. Using prostate bed tilt could be an effective measurement for assessing potential geographic miss on orthogonal images if volumetric imaging is unavailable.« less

Recommendations on rectal surveillance for colorectal cancer after subtotal colectomy in patients with inflammatory bowel disease.

PubMed

Derikx, Lauranne A A P; de Jong, Michiel E; Hoentjen, Frank

2018-05-17

Approximately 30% of patients with ulcerative colitis require a colectomy during their disease course. This substantially reduces colorectal cancer risk, although it is still possible to develop colorectal neoplasia in the remaining rectum. Although clear and well-accepted surveillance guidelines exist for patients with inflammatory bowel disease with an intact colon, specific surveillance recommendations following colectomy are less clear. Here, we aim to summarize the prevalence, incidence, and risk factors for developing colorectal cancer in patients with inflammatory bowel disease who underwent subtotal colectomy with a permanent end ileostomy and rectal stump, or with ileorectal anastomosis. Subsequently, gained insights are integrated into a proposed endoscopic surveillance strategy of the residual rectum.

[A Case of a Patient with Metastatic Rectal-Uterine Cancer from the Ascending Colon Who Underwent NOSE].

PubMed

Naito, Atsushi; Kato, Takeshi; Ishida, Tomo; Kuwahara, Ryuichi; Akiyama, Yasuki; Sakamato, Takuya; Inatome, Junichi; Murakami, Kohei; Katsura, Yoshiteru; Ohmura, Yoshiaki; Kagawa, Yoshinori; Takeno, Atsushi; Egawa, Chiyomi; Takeda, Yutaka; Tamura, Shigeyuki

2016-11-01

An 80-year-old woman had undergone a right hemicolectomy for ascending colon cancer 9 months prior to the current presentation. CT and PET-CT showed a solitary tumor measuring 55mm in diameter at the uterus and rectum. Three 5mm ports and two 12mm two ports were placed. The sigmoid colon was mobilized using a medial approach as usual in laparoscopic surgery. The rectum and uterus were mobilized and were resected. We inserted the End-catchTM in from the vagina and removed the specimen. The patient had no abdominal pain and was discharged from the hospital 9 days after the operation.

Physiological and pharmacological characterization of the larval Anopheles albimanus rectum supports a change in protein distribution and/or function in varying salinities

PubMed Central

Smith, Kristin E.; Raymond, Steven L.; Valenti, Micheala L.; Smith, Peter J.S.; Linser, Paul J.

2010-01-01

Ion regulation is a biological process crucial to the survival of mosquito larvae and a major organ responsible for this regulation is the rectum. The recta of anopheline larvae are distinct from other subfamilies of mosquitoes in several ways, yet have not yet been characterized extensively. Here we characterize the two major cell types of the anopheline rectum, DAR and non-DAR cells, using histological, physiological, and pharmacological analyses. Proton flux was measured at the basal membrane of 2%- and 50%-artificial sea water-reared An. albimanus larvae using self-referencing ion-selective microelectrodes, and the two cell types were found to differ in basal membrane proton flux. Additionally, differences in the response of that flux to pharmacological inhibitors in larvae reared in 2% versus 50% ASW indicate changes in protein function between the two rearing conditions. Finally, histological analyses suggest that the non-DAR cells are structurally suited for mediating ion transport. These data support a model of rectal ion regulation in which the non-DAR cells have a resorptive function in freshwater-reared larvae and a secretive function in saline water-reared larvae. In this way, anopheline larvae may adapt to varying salinities. PMID:20460167

Anatomical basis for impotence following haemorrhoid sclerotherapy.

PubMed Central

Pilkington, S. A.; Bateman, A. C.; Wombwell, S.; Miller, R.

2000-01-01

Impotence has been reported as a rare but important complication of sclerotherapy for haemorrhoids. The relationship between the anterior wall of the rectum and the periprostatic parasympathetic nerves responsible for penile erection was studied to investigate a potential anatomical explanation for this therapeutic complication. A tissue block containing the anal canal, rectum and prostate was removed from each of six male cadaveric subjects. The dimensions of the components of the rectal wall and the distance between the rectal lumen and parasympathetic nerves in the periprostatic plexus were measured in horizontal transverse histological sections of the tissue blocks at the level of the lower prostate gland (i.e. the correct level for sclerosant injection). The correct site of sclerosant in the submucosa was on average 0.6 mm (SD 0.3 mm) deep to the rectal mucosal surface and only 0.7 mm (SD 0.5 mm) in thickness. The nearest parasympathetic ganglion cells were a mean of only 8.1 mm (SD 2.0 mm) deep to the rectal lumen. The close proximity of the rectum to the periprostatic parasympathetic nerves defines an anatomical basis for impotence following sclerotherapy. This emphasises the need for all practitioners to be particularly careful when injecting in this area and for strict supervision of trainees. Images Figure 1 Figure 2 PMID:11041026

Brachytherapy of prostate cancer after colectomy for colorectal cancer: pilot experience.

PubMed

Koutrouvelis, Panos G; Theodorescu, Dan; Katz, Stuart; Lailas, Niko; Hendricks, Fred

2005-01-01

We present a method of brachytherapy for prostate cancer using a 3-dimensional stereotactic system and computerized tomography guidance in patients without a rectum due to previous treatment for colorectal cancer. From June 1994 to November 2003 a cohort of 800 patients were treated with brachytherapy for prostate cancer. Four patients had previously been treated for colorectal cancer with 4,500 cGy external beam radiation therapy, abdominoperineal resection and chemotherapy, while 1 underwent abdominoperineal resection alone for ulcerative colitis. Because of previous radiation therapy, these patients were not candidates for salvage external beam radiation therapy or radical prostatectomy and they had no rectum for transrectal ultrasound guided transperineal brachytherapy or cryotherapy. A previously described, 3-dimensional stereotactic system was used for brachytherapy in these patients. The prescribed radiation dose was 120 to 144 Gy with iodine seeds in rapid strand format. Patient followup included clinical examination and serum prostate specific antigen measurement. Average followup was 18.6 months. Four patients had excellent biochemical control, while 1 had biochemical failure. Patients did not experience any gastrointestinal morbidity. One patient had a stricture of the distal ureter, requiring a stent. Three-dimensional computerized tomography guided brachytherapy for prostate cancer in patients with a history of colorectal cancer who have no rectum is a feasible method of treatment.

Absorbed dose calculations in a brachytherapy pelvic phantom using the Monte Carlo method

PubMed Central

Rodríguez, Miguel L.; deAlmeida, Carlos E.

2002-01-01

Monte Carlo calculations of the absorbed dose at various points of a brachytherapy anthropomorphic phantom are presented. The phantom walls and internal structures are made of polymethylmethacrylate and its external shape was taken from a female Alderson phantom. A complete Fletcher‐Green type applicator with the uterine tandem was fixed at the bottom of the phantom reproducing a typical geometrical configuration as that attained in a gynecological brachytherapy treatment. The dose rate produced by an array of five 137Cs CDC‐J type sources placed in the applicator colpostats and the uterine tandem was evaluated by Monte Carlo simulations using the code penelope at three points: point A, the rectum, and the bladder. The influence of the applicator in the dose rate was evaluated by comparing Monte Carlo simulations of the sources alone and the sources inserted in the applicator. Differences up to 56% in the dose may be observed for the two cases in the planes including the rectum and bladder. The results show a reduction of the dose of 15.6%, 14.0%, and 5.6% in the rectum, bladder, and point A respectively, when the applicator wall and shieldings are considered. PACS number(s): 87.53Jw, 87.53.Wz, 87.53.Vb, 87.66.Xa PMID:12383048

Perineal colostomy: an alternative to avoid permanent abdominal colostomy: operative technique, results and reflection.

PubMed

da Silva, Alcino Lázaro; Hayck, Johnny; Deoti, Beatriz

2014-01-01

The most common injury to indicate definitive stoma is rectal cancer. Despite advances in surgical treatment, the abdominoperineal resection is still the most effective operation in radical treatment of malignancies of the distal rectum invading the sphincter and anal canal. Even with all the effort that surgeons have to preserve anal sphincters, abdominoperineal amputation is still indicated, and a definitive abdominal colostomy is necessary. This surgery requires patients to live with a definitive abdominal colostomy, which is a condition that modify body image, is not without morbidity and has great impact on the quality of life. To evaluate the technique of abdominoperineal amputation with perineal colostomy with irrigation as an alternative to permanent abdominal colostomy. Retrospective analysis of medical records of 55 patients underwent abdominoperineal resection of the rectum with perineal colostomy in the period 1989-2010. The mean age was 58 years, 40 % men and 60 % women. In 94.5% of patients the indication for surgery was for cancer of the rectum. In some patients were made three valves, other two valves and in the remaining no valve at all. Complications were: mucosal prolapse, necrosis of the lowered segment and stenosis. The abdominoperineal amputation with perineal colostomy is a good therapeutic option in the armamentarium of the surgical treatment of rectal cancer.

Use of a spiral rectal diaphragm technique to control anal sphincter incontinence in a cat.

PubMed

Pavletic, Michael; Mahn, Matt; Duddy, Jean

2012-09-15

A 10-year-old castrated male domestic shorthair cat was examined for a mass involving the right anal sac region. The mass was diagnosed as a fibrosarcoma, and resulted in progressive tenesmus, requiring repeated resection. Surgical removal of the fibrosarcoma was performed on 4 occasions, including complete resection of the anal sphincter muscles and portions of the rectum. A perineal urethrostomy was required during the third surgical procedure secondary to tumor invasion of the preputial tissues. To reduce involuntary loss of feces, the remaining rectal wall was rotated approximately 225° prior to surgical closure during the second, third, and fourth surgical procedures. This procedure created a natural spiral diaphragm within the rectal lumen. The elastic spiral barrier reduced inadvertent fecal loss and facilitated fecal distention of the terminal portion of the colon, allowing the patient to anticipate the impending passage of feces and to use the litter tray on a daily basis. With complete loss of the terminal portion of the rectum and anal sphincter muscles, spiraling the rectum created a deformable threshold barrier to reduce excessive loss of stool secondary to fecal incontinence. On the basis of the positive outcome in this patient, this novel technique may be a useful option to consider for the treatment of cats with loss of anal sphincter function.

Functional morphology of digestion in the stomachless, piscivorous needlefishes Tylosurus gavialoides and Strongylura leiura ferox (Teleostei: Beloniformes).

PubMed

Manjakasy, Jennifer M; Day, Ryan D; Kemp, Anne; Tibbetts, Ian R

2009-10-01

Belonidae are unusual in that they are carnivorous but lack a stomach and have a straight, short gut. To develop a functional morphological model for this unusual system the gut contents and alimentary tract morphology of Tylosurus gavialoides and Strongylura leiura ferox were investigated. The posterior orientation of the majority of the pharyngeal teeth supports the swallowing of whole large prey, but not their mastication. Mucogenic cells are abundant in the mucosa lining, particularly the esophagus, and their secretions are likely to protect the gut lining from damage while lubricating passage of the prey. Esophagus, anterior intestine, posterior intestine, and rectum all have highly reticulate mucosae. The anterior three gut sections are distensible to accommodate the passage of prey. However, following ingestion large prey are passed to the highly distensible posterior intestine where they rest head first against the ileorectal valve. Alimentary pH ranges from neutral to weakly acidic. Fish prey is digested head first with the head being largely digested while the remainder of the body is still intact. The nondistensibility of the rectum and the small aperture provided by the ileorectal valve suggest the products of intestinal digestion are either small particulates or fluids that pass into rectum where they are absorbed. 2009 Wiley-Liss, Inc.

Trypanosoma cruzi: effects of azadirachtin and ecdysone on the dynamic development in Rhodnius prolixus larvae.

PubMed

Cortez, M R; Provençano, A; Silva, C E; Mello, C B; Zimmermann, L T; Schaub, G A; Garcia, E S; Azambuja, P; Gonzalez, M S

2012-07-01

The effects of azadirachtin and ecdysone on the Trypanosoma cruzi population in the Rhodnius prolixus gut were investigated. T. cruzi were rarely found in the gut compartments of azadirachtin-treated larvae. High parasite numbers were observed in the stomach of the control and ecdysone groups until 10 days after treatment and in the small intestine and rectum until 25 days after treatment. High percentages of round forms developed in the stomachs of all groups, whereas azadirachtin blocked the development of protozoan intermediate forms. This effect was counteracted by ecdysone therapy. In the small intestine and rectum, epimastigotes predominated for all groups, but more of their intermediates developed in the control and ecdysone groups. Azadirachtin supported the development of round forms and their intermediates into trypomastigotes. In the rectum, trypomastigotes did not develop in the azadirachtin group and developed much later after ecdysone therapy. The parallel between the effects of azadirachtin and ecdysone on the host and parasite development is discussed on the basis of the present results because ecdysone appears to act directly or indirectly in determining the synchronic development of T. cruzi forms from round to epimastigotes, but not metacyclic trypomastigotes, in the invertebrate vector. Copyright © 2012 Elsevier Inc. All rights reserved.

Potential use of bacterial community succession for estimating post-mortem interval as revealed by high-throughput sequencing

PubMed Central

Guo, Juanjuan; Fu, Xiaoliang; Liao, Huidan; Hu, Zhenyu; Long, Lingling; Yan, Weitao; Ding, Yanjun; Zha, Lagabaiyila; Guo, Yadong; Yan, Jie; Chang, Yunfeng; Cai, Jifeng

2016-01-01

Decomposition is a complex process involving the interaction of both biotic and abiotic factors. Microbes play a critical role in the process of carrion decomposition. In this study, we analysed bacterial communities from live rats and rat remains decomposed under natural conditions, or excluding sarcosaphagous insect interference, in China using Illumina MiSeq sequencing of 16S rRNA gene amplicons. A total of 1,394,842 high-quality sequences and 1,938 singleton operational taxonomic units were obtained. Bacterial communities showed notable variation in relative abundance and became more similar to each other across body sites during the decomposition process. As decomposition progressed, Proteobacteria (mostly Gammaproteobacteria) became the predominant phylum in both the buccal cavity and rectum, while Firmicutes and Bacteroidetes in the mouth and rectum, respectively, gradually decreased. In particular, the arrival and oviposition of sarcosaphagous insects had no obvious influence on bacterial taxa composition, but accelerated the loss of biomass. In contrast to the rectum, the microbial community structure in the buccal cavity of live rats differed considerably from that of rats immediately after death. Although this research indicates that bacterial communities can be used as a “microbial clock” for the estimation of post-mortem interval, further work is required to better understand this concept. PMID:27052375

SU-E-J-133: Autosegmentation of Linac CBCT: Improved Accuracy Via Penalized Likelihood Reconstruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Y

2015-06-15

Purpose: To improve the quality of kV X-ray cone beam CT (CBCT) for use in radiotherapy delivery assessment and re-planning by using penalized likelihood (PL) iterative reconstruction and auto-segmentation accuracy of the resulting CBCTs as an image quality metric. Methods: Present filtered backprojection (FBP) CBCT reconstructions can be improved upon by PL reconstruction with image formation models and appropriate regularization constraints. We use two constraints: 1) image smoothing via an edge preserving filter, and 2) a constraint minimizing the differences between the reconstruction and a registered prior image. Reconstructions of prostate therapy CBCTs were computed with constraint 1 alone andmore » with both constraints. The prior images were planning CTs(pCT) deformable-registered to the FBP reconstructions. Anatomy segmentations were done using atlas-based auto-segmentation (Elekta ADMIRE). Results: We observed small but consistent improvements in the Dice similarity coefficients of PL reconstructions over the FBP results, and additional small improvements with the added prior image constraint. For a CBCT with anatomy very similar in appearance to the pCT, we observed these changes in the Dice metric: +2.9% (prostate), +8.6% (rectum), −1.9% (bladder). For a second CBCT with a very different rectum configuration, we observed +0.8% (prostate), +8.9% (rectum), −1.2% (bladder). For a third case with significant lateral truncation of the field of view, we observed: +0.8% (prostate), +8.9% (rectum), −1.2% (bladder). Adding the prior image constraint raised Dice measures by about 1%. Conclusion: Efficient and practical adaptive radiotherapy requires accurate deformable registration and accurate anatomy delineation. We show here small and consistent patterns of improved contour accuracy using PL iterative reconstruction compared with FBP reconstruction. However, the modest extent of these results and the pattern of differences across CBCT cases suggest that significant further development will be required to make CBCT useful to adaptive radiotherapy.« less

Dosimetric evaluation of planning target volume margin reduction for prostate cancer via image-guided intensity-modulated radiation therapy

NASA Astrophysics Data System (ADS)

Hwang, Taejin; Kang, Sei-Kwon; Cheong, Kwang-Ho; Park, Soah; Yoon, Jai-Woong; Han, Taejin; Kim, Haeyoung; Lee, Meyeon; Kim, Kyoung-Joo; Bae, Hoonsik; Suh, Tae-Suk

2015-07-01

The aim of this study was to quantitatively estimate the dosimetric benefits of the image-guided radiation therapy (IGRT) system for the prostate intensity-modulated radiation therapy (IMRT) delivery. The cases of eleven patients who underwent IMRT for prostate cancer without a prostatectomy at our institution between October 2012 and April 2014 were retrospectively analyzed. For every patient, clinical target volume (CTV) to planning target volume (PTV) margins were uniformly used: 3 mm, 5 mm, 7 mm, 10 mm, 12 mm, and 15 mm. For each margin size, the IMRT plans were independently optimized by one medical physicist using Pinnalce3 (ver. 8.0.d, Philips Medical System, Madison, WI) in order to maintain the plan quality. The maximum geometrical margin (MGM) for every CT image set, defined as the smallest margin encompassing the rectum at least at one slice, was between 13 mm and 26 mm. The percentage rectum overlapping PTV (%V ROV ), the rectal normal tissue complication probability (NTCP) and the mean rectal dose (%RD mean ) increased in proportion to the increase of PTV margin. However the bladder NTCP remained around zero to some extent regardless of the increase of PTV margin while the percentage bladder overlapping PTV (%V BOV ) and the mean bladder dose (%BD mean ) increased in proportion to the increase of PTV margin. Without relatively large rectum or small bladder, the increase observed for rectal NTCP, %RDmean and %BD mean per 1-mm PTV margin size were 1.84%, 2.44% and 2.90%, respectively. Unlike the behavior of the rectum or the bladder, the maximum dose on each femoral head had little effect on PTV margin. This quantitative study of the PTV margin reduction supported that IG-IMRT has enhanced the clinical effects over prostate cancer with the reduction of normal organ complications under the similar level of PTV control.

Reduced dose to urethra and rectum with the use of variable needle spacing in prostate brachytherapy: a potential role for robotic technology

PubMed Central

Vyas, Shilpa; Le, Yi; Zhang, Zhe; Armour, Woody

2015-01-01

Purpose Several robotic delivery systems for prostate brachytherapy are under development or in pre-clinical testing. One of the features of robotic brachytherapy is the ability to vary spacing of needles at non-fixed intervals. This feature may play an important role in prostate brachytherapy, which is traditionally template-based with fixed needle spacing of 0.5 cm. We sought to quantify potential reductions in the dose to urethra and rectum by utilizing variable needle spacing, as compared to fixed needle spacing. Material and methods Transrectal ultrasound images from 10 patients were used by 3 experienced planners to create 120 treatment plans. Each planner created 4 plan variations per patient with respect to needle positions: 125I fixed spacing, 125I variable spacing, 103Pd fixed spacing, and 103Pd variable spacing. The primary planning objective was to achieve a prostate V100 of 100% while minimizing dose to urethra and rectum. Results All plans met the objective of achieving prostate V100 of 100%. Combined results for all plans show statistically significant improvements in all assessed dosimetric variables for urethra (Umax, Umean, D30, D5) and rectum (Rmax, Rmean, RV100) when using variable spacing. The dose reductions for mean and maximum urethra dose using variable spacing had p values of 0.011 and 0.024 with 103Pd, and 0.007 and 0.029 with 125I plans. Similarly dose reductions for mean and maximum rectal dose using variable spacing had p values of 0.007 and 0.052 with 103Pd, and 0.012 and 0.037 with 125I plans. Conclusions The variable needle spacing achievable by the use of robotics in prostate brachytherapy allows for reductions in both urethral and rectal planned doses while maintaining prostate dose coverage. Such dosimetric advantages have the potential in translating to significant clinical benefits with the use of robotic brachytherapy. PMID:26622227

Helical Tomotherapy vs. Intensity-Modulated Proton Therapy for Whole Pelvis Irradiation in High-Risk Prostate Cancer Patients: Dosimetric, Normal Tissue Complication Probability, and Generalized Equivalent Uniform Dose Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Widesott, Lamberto, E-mail: widesott@yahoo.it; Pierelli, Alessio; Fiorino, Claudio

2011-08-01

Purpose: To compare intensity-modulated proton therapy (IMPT) and helical tomotherapy (HT) treatment plans for high-risk prostate cancer (HRPCa) patients. Methods and Materials: The plans of 8 patients with HRPCa treated with HT were compared with IMPT plans with two quasilateral fields set up (-100{sup o}; 100{sup o}) and optimized with the Hyperion treatment planning system. Both techniques were optimized to simultaneously deliver 74.2 Gy/Gy relative biologic effectiveness (RBE) in 28 fractions on planning target volumes (PTVs)3-4 (P + proximal seminal vesicles), 65.5 Gy/Gy(RBE) on PTV2 (distal seminal vesicles and rectum/prostate overlapping), and 51.8 Gy/Gy(RBE) to PTV1 (pelvic lymph nodes). Normalmore » tissue calculation probability (NTCP) calculations were performed for the rectum, and generalized equivalent uniform dose (gEUD) was estimated for the bowel cavity, penile bulb and bladder. Results: A slightly better PTV coverage and homogeneity of target dose distribution with IMPT was found: the percentage of PTV volume receiving {>=}95% of the prescribed dose (V{sub 95%}) was on average >97% in HT and >99% in IMPT. The conformity indexes were significantly lower for protons than for photons, and there was a statistically significant reduction of the IMPT dosimetric parameters, up to 50 Gy/Gy(RBE) for the rectum and bowel and 60 Gy/Gy(RBE) for the bladder. The NTCP values for the rectum were higher in HT for all the sets of parameters, but the gain was small and in only a few cases statistically significant. Conclusions: Comparable PTV coverage was observed. Based on NTCP calculation, IMPT is expected to allow a small reduction in rectal toxicity, and a significant dosimetric gain with IMPT, both in medium-dose and in low-dose range in all OARs, was observed.« less

SU-G-TeP2-10: Feasibility of Newly Designed Applicator for High Dose Rate Brachytherapy Treatment of Patients with Vaginal Vault Recurrence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, V; Wong, M; Chan, M

Purpose: To compare the dose of an in-house 3D-printed gynecology applicator (TMHGA) for vaginal vault recurrence of corpus cancer patients after operation for high dose rate brachytherapy treatment with commercially available applicators. Methods: A newly designed applicator is made from 3D-printing methods using ABSM30i. The isodose of the applicator is compared with Elekta multi-channel (MC) applicator and titanium Rotterdam applicator with coupling central tube and vaginal cylinder (RC). Three plans are created using three applicators in a CT set of water phantom. The applicators are anchored using the applicator library and implant library in the Elekta Oncentra treatment planning systemmore » (ver.4.5). The rectum is mimicked by creating a 2cm diameter cylinder, with a distance 1mm posteriorly away from the high risk CTV (HR-CTV). Similarly, the bladder is replicated by a 6cm diameter cylinder with distance 1mm anteriorly from the HR-CTV. Three plans are all normalized 1.5cm superior, 0.5cm anterior and 0.5cm posterior of the applicator surface. By fixing D90 of HR-CTV to 6Gy, the D2cc of rectum and bladder of three plans are compared. Results: The D2cc of the bladder for using TMHGA is lower than MC and RC by 14.0% and 11.9% respectively. While the D2cc of the rectum for using TMHGA is lower than MC and RC by 18.9% and 12.4% respectively. The total treatment time of TMHGA plan is shorter than MC and RC by 11.2% and 12.9%. Conclusion: The applicator created via 3D printing delivers a lower dose to the bladder and the rectum while keeping the same coverage to HR-CTV as other commercially available applicators. Additionally, the new applicator resulted in a reduction of treatment time, which is always welcome.« less

Dosimetric Implications of an Injection of Hyaluronic Acid for Preserving the Rectal Wall in Prostate Stereotactic Body Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr; Udrescu, Corina; Department of Medical Physics, Centre Hospitalier Lyon Sud, Pierre Benite

2014-02-01

Purpose: This study assessed the contribution of ahyaluronic acid (HA) injection between the rectum and the prostate to reducing the dose to the rectal wall in stereotactic body radiation therapy (SBRT). Methods and Materials: As part of a phase 2 study of hypofractionated radiation therapy (62 Gy in 20 fractions), the patients received a transperineal injection of 10 cc HA between the rectum and the prostate. A dosimetric computed tomographic (CT) scan was systematically performed before (CT1) and after (CT2) the injection. Two 9-beam intensity modulated radiation therapy-SBRT plans were optimized for the first 10 patients on both CTs accordingmore » to 2 dosage levels: 5 × 6.5 Gy (PlanA) and 5 × 8.5 Gy (PlanB). Rectal wall parameters were compared with a dose–volume histogram, and the prostate–rectum separation was measured at 7 levels of the prostate on the center line of the organ. Results: For both plans, the average volume of the rectal wall receiving the 90% isodose line (V90%) was reduced up to 90% after injection. There was no significant difference (P=.32) between doses received by the rectal wall on CT1 and CT2 at the base of the prostate. This variation became significant from the median plane to the apex of the prostate (P=.002). No significant differences were found between PlanA without HA and PlanB with HA for each level of the prostate (P=.77, at the isocenter of the prostate). Conclusions: HA injection significantly reduced the dose to the rectal wall and allowed a dose escalation from 6.5 Gy to 8.5 Gy without increasing the dose to the rectum. A phase 2 study is under way in our department to assess the rate of acute and late rectal toxicities when SBRT (5 × 8.5 Gy) is combined with an injection of HA.« less

Colonic spread of three rectally administered mesalazine (Pentasa) dosage forms in healthy volunteers as assessed by gamma scintigraphy.

PubMed

Brown, J; Haines, S; Wilding, I R

1997-08-01

Rectal administration of enemas, foams and suppositories is the most efficient method of delivering locally-acting drugs to the distal colon, sigmoid colon and rectum. Healthy volunteers provide an effective population to compare different formulations for rectal drug delivery. However, there is still only limited comparative information available on the dispersion of such dosage forms in human subjects. Therefore, the objective of this scintigraphic study was to compare colonic spread of an enema, a rectal foam and a suppository formulation in healthy volunteers. This was a randomized, crossover study in eight healthy male volunteers. Each received Pentasa rectal formulations as either a 100 mL suspension enema (1 g mesalazine), one actuation of a non-CFC propellant rectal foam (1 g mesalazine in 5 mL concentrate, expanding to 40 mL on actuation), or one suppository (1 g mesalazine) on three separate occasions. The spread of the radiolabelled formulations was assessed over a 4-h period by gamma scintigraphy. The formulations were retained by all subjects for the whole of the 4-h imaging period. The enema spread to the splenic flexure in 7 out of 8 subjects, but was retained in the rectum and sigmoid colon in one individual. The foam spread as far as the descending colon in four subjects. In the remaining individuals the foam was retained in the rectum and sigmoid colon. The spread of the suppository was limited and confined to the rectum. The findings of this study are consistent with previous research and support the intended clinical uses of the enema, foam and suppository formulations to treat distal ulcerative colitis, proctosigmoiditis and proctitis, respectively. The results highlight the potential of gamma scintigraphy in providing in vivo 'proof of concept' data to help verify the targeting of pharmaceutical products to their intended site of delivery.

Assessment of normal tissue complications following prostate cancer irradiation: Comparison of radiation treatment modalities using NTCP models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takam, Rungdham; Bezak, Eva; Yeoh, Eric E.

2010-09-15

Purpose: Normal tissue complication probability (NTCP) of the rectum, bladder, urethra, and femoral heads following several techniques for radiation treatment of prostate cancer were evaluated applying the relative seriality and Lyman models. Methods: Model parameters from literature were used in this evaluation. The treatment techniques included external (standard fractionated, hypofractionated, and dose-escalated) three-dimensional conformal radiotherapy (3D-CRT), low-dose-rate (LDR) brachytherapy (I-125 seeds), and high-dose-rate (HDR) brachytherapy (Ir-192 source). Dose-volume histograms (DVHs) of the rectum, bladder, and urethra retrieved from corresponding treatment planning systems were converted to biological effective dose-based and equivalent dose-based DVHs, respectively, in order to account for differences inmore » radiation treatment modality and fractionation schedule. Results: Results indicated that with hypofractionated 3D-CRT (20 fractions of 2.75 Gy/fraction delivered five times/week to total dose of 55 Gy), NTCP of the rectum, bladder, and urethra were less than those for standard fractionated 3D-CRT using a four-field technique (32 fractions of 2 Gy/fraction delivered five times/week to total dose of 64 Gy) and dose-escalated 3D-CRT. Rectal and bladder NTCPs (5.2% and 6.6%, respectively) following the dose-escalated four-field 3D-CRT (2 Gy/fraction to total dose of 74 Gy) were the highest among analyzed treatment techniques. The average NTCP for the rectum and urethra were 0.6% and 24.7% for LDR-BT and 0.5% and 11.2% for HDR-BT. Conclusions: Although brachytherapy techniques resulted in delivering larger equivalent doses to normal tissues, the corresponding NTCPs were lower than those of external beam techniques other than the urethra because of much smaller volumes irradiated to higher doses. Among analyzed normal tissues, the femoral heads were found to have the lowest probability of complications as most of their volume was irradiated to lower equivalent doses compared to other tissues.« less

A knowledge-based approach to improving and homogenizing intensity modulated radiation therapy planning quality among treatment centers: an example application to prostate cancer planning.

PubMed

Good, David; Lo, Joseph; Lee, W Robert; Wu, Q Jackie; Yin, Fang-Fang; Das, Shiva K

2013-09-01

Intensity modulated radiation therapy (IMRT) treatment planning can have wide variation among different treatment centers. We propose a system to leverage the IMRT planning experience of larger institutions to automatically create high-quality plans for outside clinics. We explore feasibility by generating plans for patient datasets from an outside institution by adapting plans from our institution. A knowledge database was created from 132 IMRT treatment plans for prostate cancer at our institution. The outside institution, a community hospital, provided the datasets for 55 prostate cancer cases, including their original treatment plans. For each "query" case from the outside institution, a similar "match" case was identified in the knowledge database, and the match case's plan parameters were then adapted and optimized to the query case by use of a semiautomated approach that required no expert planning knowledge. The plans generated with this knowledge-based approach were compared with the original treatment plans at several dose cutpoints. Compared with the original plan, the knowledge-based plan had a significantly more homogeneous dose to the planning target volume and a significantly lower maximum dose. The volumes of the rectum, bladder, and femoral heads above all cutpoints were nominally lower for the knowledge-based plan; the reductions were significantly lower for the rectum. In 40% of cases, the knowledge-based plan had overall superior (lower) dose-volume histograms for rectum and bladder; in 54% of cases, the comparison was equivocal; in 6% of cases, the knowledge-based plan was inferior for both bladder and rectum. Knowledge-based planning was superior or equivalent to the original plan in 95% of cases. The knowledge-based approach shows promise for homogenizing plan quality by transferring planning expertise from more experienced to less experienced institutions. Copyright © 2013 Elsevier Inc. All rights reserved.

Dosimetric and radiobiologic comparison of 3D conformal versus intensity modulated planning techniques for prostate bed radiotherapy.

PubMed

Koontz, Bridget F; Das, Shiva; Temple, Kathy; Bynum, Sigrun; Catalano, Suzanne; Koontz, Jason I; Montana, Gustavo S; Oleson, James R

2009-01-01

Adjuvant radiotherapy for locally advanced prostate cancer improves biochemical and clinical disease-free survival. While comparisons in intact prostate cancer show a benefit for intensity modulated radiation therapy (IMRT) over 3D conformal planning, this has not been studied for post-prostatectomy radiotherapy (RT). This study compares normal tissue and target dosimetry and radiobiological modeling of IMRT vs. 3D conformal planning in the postoperative setting. 3D conformal plans were designed for 15 patients who had been treated with IMRT planning for salvage post-prostatectomy RT. The same computed tomography (CT) and target/normal structure contours, as well as prescription dose, was used for both IMRT and 3D plans. Normal tissue complication probabilities (NTCPs) were calculated based on the dose given to the bladder and rectum by both plans. Dose-volume histogram and NTCP data were compared by paired t-test. Bladder and rectal sparing were improved with IMRT planning compared to 3D conformal planning. The volume of the bladder receiving at least 75% (V75) and 50% (V50) of the dose was significantly reduced by 28% and 17%, respectively (p = 0.002 and 0.037). Rectal dose was similarly reduced, V75 by 33% and V50 by 17% (p = 0.001 and 0.004). While there was no difference in the volume of rectum receiving at least 65 Gy (V65), IMRT planning significant reduced the volume receiving 40 Gy or more (V40, p = 0.009). Bladder V40 and V65 were not significantly different between planning modalities. Despite these dosimetric differences, there was no significant difference in the NTCP for either bladder or rectal injury. IMRT planning reduces the volume of bladder and rectum receiving high doses during post-prostatectomy RT. Because of relatively low doses given to the bladder and rectum, there was no statistically significant improvement in NTCP between the 3D conformal and IMRT plans.

The effect of 6 and 15 MV on intensity-modulated radiation therapy prostate cancer treatment: plan evaluation, tumour control probability and normal tissue complication probability analysis, and the theoretical risk of secondary induced malignancies

PubMed Central

Hussein, M; Aldridge, S; Guerrero Urbano, T; Nisbet, A

2012-01-01

Objective The aim of this study was to investigate the effect of 6 and 15-MV photon energies on intensity-modulated radiation therapy (IMRT) prostate cancer treatment plan outcome and to compare the theoretical risks of secondary induced malignancies. Methods Separate prostate cancer IMRT plans were prepared for 6 and 15-MV beams. Organ-equivalent doses were obtained through thermoluminescent dosemeter measurements in an anthropomorphic Aldersen radiation therapy human phantom. The neutron dose contribution at 15 MV was measured using polyallyl-diglycol-carbonate neutron track etch detectors. Risk coefficients from the International Commission on Radiological Protection Report 103 were used to compare the risk of fatal secondary induced malignancies in out-of-field organs and tissues for 6 and 15 MV. For the bladder and the rectum, a comparative evaluation of the risk using three separate models was carried out. Dose–volume parameters for the rectum, bladder and prostate planning target volume were evaluated, as well as normal tissue complication probability (NTCP) and tumour control probability calculations. Results There is a small increased theoretical risk of developing a fatal cancer from 6 MV compared with 15 MV, taking into account all the organs. Dose–volume parameters for the rectum and bladder show that 15 MV results in better volume sparing in the regions below 70 Gy, but the volume exposed increases slightly beyond this in comparison with 6 MV, resulting in a higher NTCP for the rectum of 3.6% vs 3.0% (p=0.166). Conclusion The choice to treat using IMRT at 15 MV should not be excluded, but should be based on risk vs benefit while considering the age and life expectancy of the patient together with the relative risk of radiation-induced cancer and NTCPs. PMID:22010028

Impact of a commercially available model-based dose calculation algorithm on treatment planning of high-dose-rate brachytherapy in patients with cervical cancer.

PubMed

Abe, Kota; Kadoya, Noriyuki; Sato, Shinya; Hashimoto, Shimpei; Nakajima, Yujiro; Miyasaka, Yuya; Ito, Kengo; Umezawa, Rei; Yamamoto, Takaya; Takahashi, Noriyoshi; Takeda, Ken; Jingu, Keiichi

2018-03-01

We evaluated the impact of model-based dose calculation algorithms (MBDCAs) on high-dose-rate brachytherapy (HDR-BT) treatment planning for patients with cervical cancer. Seven patients with cervical cancer treated using HDR-BT were studied. Tandem and ovoid applicators were used in four patients, a vaginal cylinder in one, and interstitial needles in the remaining two patients. MBDCAs were applied to the Advanced Collapsed cone Engine (ACE; Elekta, Stockholm, Sweden). All plans, which were originally calculated using TG-43, were re-calculated using both ACE and Monte Carlo (MC) simulations. Air was used as the rectal material. The mean difference in the rectum D2cm3 between ACErec-air and MCrec-air was 8.60 ± 4.64%, whereas that in the bladder D2cm3 was -2.80 ± 1.21%. Conversely, in the small group analysis (n = 4) using water instead of air as the rectal material, the mean difference in the rectum D2cm3 between TG-43 and ACErec-air was 11.87 ± 2.65%, whereas that between TG-43 and ACErec-water was 0.81 ± 2.04%, indicating that the use of water as the rectal material reduced the difference in D2cm3 between TG-43 and ACE. Our results suggested that the differences in the dose-volume histogram (DVH) parameters of TG-43 and ACE were large for the rectum when considerable air (gas) volume was present in it, and that this difference was reduced when the air (gas) volume was reduced. Also, ACE exhibited better dose calculation accuracy than that of TG-43 in this situation. Thus, ACE may be able to calculate the dose more accurately than TG-43 for HDR-BT in treating cervical cancers, particularly for patients with considerable air (gas) volume in the rectum.

Profiling of composition and metabolic activities of the colonic microflora of growing pigs fed diets supplemented with prebiotic oligosaccharides.

PubMed

Mountzouris, Konstantinos C; Balaskas, Christos; Fava, Fransesca; Tuohy, Kieran M; Gibson, Glenn R; Fegeros, K

2006-08-01

It is evident that quantitative information on different microbial groups and their contribution in terms of activity in the gastrointestinal (GI) tract of humans and animals is required in order to formulate functional diets targeting improved gut function and host health. In this work, quantitative information on levels and spatial distributions of Bacteroides spp, Eubacterium spp, Clostridium spp, Escherichia coli, Bifidobacterium spp and Lactobacillus/Enterococcus spp. along the porcine large intestine was investigated using 16S rRNA targeted probes and fluorescent in situ hybridisation (FISH). Caecum, ascending colon (AC) and rectum luminal digesta from three groups of individually housed growing pigs fed either a corn-soybean basal diet (CON diet) or a prebiotic diet containing 10 g/kg oligofructose (FOS diet) or trans-galactooligosaccharides (TOS diet) at the expense of cornstarch were analysed. DAPI staining was used to enumerate total number of cells in the samples. Populations of total cells, Bacteroides, Eubacterium, Clostridium and Bifidobacterium declined significantly (P < 0.05) from caecum to rectum, and were not affected by dietary treatments. Populations of Lactobacillus/Enterococcus and E. coli did not differ throughout the large intestine. The relative percent (%) contribution of each bacterial group to the total cell count did not differ between caecum and rectum, with the exception of Eubacterium that was higher in the AC digesta. FISH analysis showed that the sum of all bacterial groups made up a small percentage of the total cells, which was 12.4%, 21.8% and 10.3% in caecum, AC and rectum, respectively. This supports the view that in swine, the diversity of GI microflora might be higher compared to other species. In terms of microflora metabolic activity, the substantially higher numerical trends seen in FOS and TOS treatments regarding total volatile fatty acid, acetate concentrations and glycolytic activities, it could be postulated that FOS and TOS promoted saccharolytic activities in the porcine colon.

SU-E-T-10: A Clinical Implementation and the Dosimetric Evidence in High Dose Rate Vaginal Multichannel Applicator Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Syh, J; Syh, J; Patel, B

2015-06-15

Purpose: The multichannel cylindrical applicator has a distinctive modification of the traditional single channel cylindrical applicator. The novel multichannel applicator has additional peripheral channels that provide more flexibility both in treatment planning process and outcomes. To protect by reducing doses to adjacent organ at risk (OAR) while maintaining target coverage with inverse plan optimization are the goals for such novel Brachytherapy device. Through a series of comparison and analysis of reults in more than forty patients who received HDR Brachytherapy using multichannel vaginal applicator, this procedure has been implemented in our institution. Methods: Multichannel planning was CT image based. Themore » CTV of 5mm vaginal cuff rind with prescribed length was well reconstructed as well as bladder and rectum. At least D95 of CTV coverage is 95% of prescribed dose. Multichannel inverse plan optimization algorithm not only shapes target dose cloud but set dose avoids to OAR’s exclusively. The doses of D2cc, D5cc and D5; volume of V2Gy in OAR’s were selected to compare with single channel results when sole central channel is only possibility. Results: Study demonstrates plan superiorly in OAR’s doe reduction in multi-channel plan. The D2cc of the rectum and bladder were showing a little lower for multichannel vs. single channel. The V2Gy of the rectum was 93.72% vs. 83.79% (p=0.007) for single channel vs. multichannel respectively. Absolute reduced mean dose of D5 by multichannel was 17 cGy (s.d.=6.4) and 44 cGy (s.d.=15.2) in bladder and rectum respectively. Conclusion: The optimization solution in multichannel was to maintain D95 CTV coverage while reducing the dose to OAR’s. Dosimetric advantage in sparing critical organs by using a multichannel applicator in HDR Brachytherapy treatment of the vaginal cuff is so promising and has been implemented clinically.« less

SU-F-T-26: A Study of the Consistency of Brachytherapy Treatments for Vaginal Cuff

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shojaei, M; Pella, S; Dumitru, N

2016-06-15

Purpose: To evaluate to treatment consistency over the total number of fractions when treatment what HDR brachytherapy using the ML cylinders. At the same time the dosimetric impact on the critical organs is monitored over the total number of fractions. Methods: A retrospective analysis of 10 patients treated with Cylinder applicators, from 2015–2016 were considered for this study. The CT scans of these patients, taken before each treatment were separately imported in to the treatment planning system and paired with the initial CT scan after completing the contouring. Two sets of CT images were fused together with respective to themore » applicator, using landmark registration. The doses of each plan were imported as well and a cumulative dosimetric analysis was made for bladder, bowels, and rectum and PTV. Results: No contour of any of the OAR was exactly similar when CT images were fused on each other. The PTV volumes vary from fraction to fraction. There was always a difference between the doses received by the OARs between treatments. The maximum dose varied between 5% and 30% in rectum and bladder. The minimum dose varied between 5% and 8% in rectum and bladder. The average dose varied between 15% and 20% in rectum and bladder. Deviation in placement were noticed between fractions. Conclusion: The variation in volumes of OARs and isodoses near the OARs, indicate that the estimated doses to OARs on the planning system may not be the same dose delivered to the patient in all the fractions. There are no major differences between the prescribed dose and the delivered dose over the total number of fractions. In some cases the critical organs will benefit if the consecutive plans will made after the CT scans will be registered with the initial scan and then planned.« less

Impact of a commercially available model-based dose calculation algorithm on treatment planning of high-dose-rate brachytherapy in patients with cervical cancer

PubMed Central

Abe, Kota; Kadoya, Noriyuki; Sato, Shinya; Hashimoto, Shimpei; Nakajima, Yujiro; Miyasaka, Yuya; Ito, Kengo; Umezawa, Rei; Yamamoto, Takaya; Takahashi, Noriyoshi; Takeda, Ken; Jingu, Keiichi

2018-01-01

Abstract We evaluated the impact of model-based dose calculation algorithms (MBDCAs) on high-dose-rate brachytherapy (HDR-BT) treatment planning for patients with cervical cancer. Seven patients with cervical cancer treated using HDR-BT were studied. Tandem and ovoid applicators were used in four patients, a vaginal cylinder in one, and interstitial needles in the remaining two patients. MBDCAs were applied to the Advanced Collapsed cone Engine (ACE; Elekta, Stockholm, Sweden). All plans, which were originally calculated using TG-43, were re-calculated using both ACE and Monte Carlo (MC) simulations. Air was used as the rectal material. The mean difference in the rectum D2cm3 between ACErec-air and MCrec-air was 8.60 ± 4.64%, whereas that in the bladder D2cm3 was −2.80 ± 1.21%. Conversely, in the small group analysis (n = 4) using water instead of air as the rectal material, the mean difference in the rectum D2cm3 between TG-43 and ACErec-air was 11.87 ± 2.65%, whereas that between TG-43 and ACErec-water was 0.81 ± 2.04%, indicating that the use of water as the rectal material reduced the difference in D2cm3 between TG-43 and ACE. Our results suggested that the differences in the dose–volume histogram (DVH) parameters of TG-43 and ACE were large for the rectum when considerable air (gas) volume was present in it, and that this difference was reduced when the air (gas) volume was reduced. Also, ACE exhibited better dose calculation accuracy than that of TG-43 in this situation. Thus, ACE may be able to calculate the dose more accurately than TG-43 for HDR-BT in treating cervical cancers, particularly for patients with considerable air (gas) volume in the rectum. PMID:29378024

The effect of anterior proton beams in the setting of a prostate-rectum spacer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christodouleas, John P., E-mail: christojo@uphs.upenn.edu; Tang, Shikui; Susil, Robert C.

2013-10-01

Studies suggest that anterior beams with in vivo range verification would improve rectal dosimetry in proton therapy for prostate cancer. We investigated whether prostate-rectum spacers would enhance or diminish the benefits of anterior proton beams in these treatments. Twenty milliliters of hydrogel was injected between the prostate and rectum of a cadaver using a transperineal approach. Computed tomography (CT) and magnetic resonance (MR) images were used to generate 7 uniform scanning (US) and 7 single-field uniform dose pencil-beam scanning (PBS) plans with different beam arrangements. Pearson correlations were calculated between rectal, bladder, and femoral head dosimetric outcomes and beam arrangementmore » anterior scores, which characterize the degree to which dose is delivered anteriorly. The overall quality of each plan was compared using a virtual dose-escalation study. For US plans, rectal mean dose was inversely correlated with anterior score, but for PBS plans there was no association between rectal mean dose and anterior score. For both US and PBS plans, full bladder and empty bladder mean doses were correlated with anterior scores. For both US and PBS plans, femoral head mean doses were inversely correlated with anterior score. For US plans and a full bladder, 4 beam arrangements that included an anterior beam tied for the highest maximum prescription dose (MPD). For US plans and an empty bladder, the arrangement with 1 anterior and 2 anterior oblique beams achieved the highest MPD in the virtual dose-escalation study. The dose-escalation study did not differentiate beam arrangements for PBS. All arrangements in the dose-escalation study were limited by bladder constraints except for the arrangement with 2 posterior oblique beams. The benefits of anterior proton beams in the setting of prostate-rectum spacers appear to be proton modality dependent and may not extend to PBS.« less

Phenylbutyrate counteracts Shigella mediated downregulation of cathelicidin in rabbit lung and intestinal epithelia: a potential therapeutic strategy.

PubMed

Sarker, Protim; Ahmed, Sultan; Tiash, Snigdha; Rekha, Rokeya Sultana; Stromberg, Roger; Andersson, Jan; Bergman, Peter; Gudmundsson, Gudmundur H; Agerberth, Birgitta; Raqib, Rubhana

2011-01-01

Cathelicidins and defensins are endogenous antimicrobial peptides (AMPs) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. Oral treatment of Shigella infected rabbits with sodium butyrate (NaB) reduces clinical severity and counteracts the downregulation of cathelicidin (CAP-18) in the large intestinal epithelia. To develop novel regimen for treating infectious diseases by inducing innate immunity, we selected sodium 4-phenylbutyrate (PB), a registered drug for a metabolic disorder as a potential therapeutic candidate in a rabbit model of shigellosis. Since acute respiratory infections often cause secondary complications during shigellosis, the systemic effect of PB and NaB on CAP-18 expression in respiratory epithelia was also evaluated. The readouts were clinical outcomes, CAP-18 expression in mucosa of colon, rectum, lung and trachea (immunohistochemistry and real-time PCR) and release of the CAP-18 peptide/protein in stool (Western blot). Significant downregulation of CAP-18 expression in the epithelia of rectum and colon, the site of Shigella infection was confirmed. Interestingly, reduced expression of CAP-18 was also noticed in the epithelia of lung and trachea, indicating a systemic effect of the infection. This suggests a causative link to acute respiratory infections during shigellosis. Oral treatment with PB resulted in reduced clinical illness and upregulation of CAP-18 in the epithelium of rectum. Both PB and NaB counteracted the downregulation of CAP-18 in lung epithelium. The drug effect is suggested to be systemic as intravenous administration of NaB could also upregulate CAP-18 in the epithelia of lung, rectum and colon. Our results suggest that PB has treatment potential in human shigellosis. Enhancement of CAP-18 in the mucosal epithelia of the respiratory tract by PB or NaB is a novel discovery. This could mediate protection from secondary respiratory infections that frequently are the lethal causes in dysentery.

Phenylbutyrate Counteracts Shigella Mediated Downregulation of Cathelicidin in Rabbit Lung and Intestinal Epithelia: A Potential Therapeutic Strategy

PubMed Central

Sarker, Protim; Ahmed, Sultan; Tiash, Snigdha; Rekha, Rokeya Sultana; Stromberg, Roger; Andersson, Jan; Bergman, Peter; Gudmundsson, Gudmundur H.

2011-01-01

Background Cathelicidins and defensins are endogenous antimicrobial peptides (AMPs) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. Oral treatment of Shigella infected rabbits with sodium butyrate (NaB) reduces clinical severity and counteracts the downregulation of cathelicidin (CAP-18) in the large intestinal epithelia. Aims To develop novel regimen for treating infectious diseases by inducing innate immunity, we selected sodium 4-phenylbutyrate (PB), a registered drug for a metabolic disorder as a potential therapeutic candidate in a rabbit model of shigellosis. Since acute respiratory infections often cause secondary complications during shigellosis, the systemic effect of PB and NaB on CAP-18 expression in respiratory epithelia was also evaluated. Methods The readouts were clinical outcomes, CAP-18 expression in mucosa of colon, rectum, lung and trachea (immunohistochemistry and real-time PCR) and release of the CAP-18 peptide/protein in stool (Western blot). Principal findings Significant downregulation of CAP-18 expression in the epithelia of rectum and colon, the site of Shigella infection was confirmed. Interestingly, reduced expression of CAP-18 was also noticed in the epithelia of lung and trachea, indicating a systemic effect of the infection. This suggests a causative link to acute respiratory infections during shigellosis. Oral treatment with PB resulted in reduced clinical illness and upregulation of CAP-18 in the epithelium of rectum. Both PB and NaB counteracted the downregulation of CAP-18 in lung epithelium. The drug effect is suggested to be systemic as intravenous administration of NaB could also upregulate CAP-18 in the epithelia of lung, rectum and colon. Conclusion Our results suggest that PB has treatment potential in human shigellosis. Enhancement of CAP-18 in the mucosal epithelia of the respiratory tract by PB or NaB is a novel discovery. This could mediate protection from secondary respiratory infections that frequently are the lethal causes in dysentery. PMID:21673991

An Assessment of the Industry-Faculty Surgeon Relationship Within Colon and Rectum Surgical Training Programs.

PubMed

Patel, Sunil V; Klingel, Michelle; Sonoda, Toyooki

2016-01-01

Industry funding of surgical training programs poses a potential conflict of interest. With the recent implementation of the Sunshine Act, industry funding can be more accurately determined. To determine the financial relationship between faculty surgeons within colon and rectal fellowship programs and industry. Review of industry funding based on the first reporting period (August-December, 2013) using the Centers for Medicare and Medicaid Services online database. ACGME certified colon and rectum surgical fellowship programs. Overall, 343 Faculty surgeons from 55 colon and rectum surgical fellowship programs were identified using the American Board of Colon and Rectum Surgery website. There was complete identification of faculty surgeons in 47 (85.5%) programs, partially complete identification (i.e., >80%) in 6 (10.9%) programs, and inadequate identification of faculty in 2 (3.6%) programs. Industry funding as defined by the Sunshine Act included general payments (honorariums, consulting fees, food and beverage, and travel), research payments, and amount invested. In all, 69.1% of program directors and 59.4% of other faculty received at least one payment during the reporting period (Δ9.7%, 95% CI: -4.4% to 23.8%, p = 0.18). Program directors received higher amounts of funding than other faculty ($7072.90 vs. $2,819.29, Δ$4,253.61, 95% CI: $1132-$7375, p = 0.008). Overall, 49 of 53 (93%) programs had surgeons receive funding, with a median of 3.5 surgeons receiving funding per program. A total of 65 companies made payments to surgeons, with 80.1% of the funding categorized as general payments, 16.2% as investments, and 3.7% as research payments. Industry funding was common. This financial relationship poses a potential conflict of interest in training fellows for future practice. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

SU-E-T-281: Reduction of Treatment Times in CyberKnife Prostate SBRT Using a Water Filled Rectal Balloon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desai, P; Caroprese, B; McKellar, H

2014-06-01

Purpose: To illustrate 25% reduction in CyberKnife prostate SBRT treatment times using a water filled rectal balloon. Methods: We perform prostate SBRT using a 3800cGy in 4 fraction regimen prescribed between 51% 59% iso-dose lines to 95% of PTV using a CyberKnife System. The resultant heterogeneous dosimetry is analogous to HDR dosimetry. Our patients are treated in a feet first supine position to decrease treatment couch sag and also to position the prostate anatomy closer to the robot. CT imaging is performed with a Radiadyne Immobiloc rectal balloon filled with 45-50cc water placed firmly inside the patient's rectum. A treatmentmore » plan is developed from this CT study using Multiplan. The patient is treated every other day for 4 days using the rectal balloon for each fraction. Gold fiducials previously implanted inside the prostate are used for tracking by the CyberKnife system. Results: Critical structures comprise the usual GU anatomy of bladder, rectum, urethra, femoral-heads along with emphasis on doses to anterior rectal wall and rectal mucosa. The water filled rectal balloon localizes the rectum, which enables the physician to accurately contour both anterior rectal wall, and rectal mucosa. The balloon also has a gas release valve enabling better patient comfort. Rectum localization enables the CyberKnife system to make fewer corrections resulting in fewer treatment interruptions and time lost to re-adjustment for rectal motion, bowel filling and gas creation. Effective treatment times are reduced by 25% to approximately 45 minutes. Adoption of the balloon has required minimal change to our planning strategy and plan evaluation process. Conclusion: Patient follow-up comparisons show no difference in effectiveness of treatment with and without balloons We conclude that rectal balloons enhance patient comfort and decrease effective treatment times.« less

Reduced dose to urethra and rectum with the use of variable needle spacing in prostate brachytherapy: a potential role for robotic technology.

PubMed

Vyas, Shilpa; Le, Yi; Zhang, Zhe; Armour, Woody; Song, Daniel Y

2015-08-01

Several robotic delivery systems for prostate brachytherapy are under development or in pre-clinical testing. One of the features of robotic brachytherapy is the ability to vary spacing of needles at non-fixed intervals. This feature may play an important role in prostate brachytherapy, which is traditionally template-based with fixed needle spacing of 0.5 cm. We sought to quantify potential reductions in the dose to urethra and rectum by utilizing variable needle spacing, as compared to fixed needle spacing. Transrectal ultrasound images from 10 patients were used by 3 experienced planners to create 120 treatment plans. Each planner created 4 plan variations per patient with respect to needle positions: (125)I fixed spacing, (125)I variable spacing, (103)Pd fixed spacing, and (103)Pd variable spacing. The primary planning objective was to achieve a prostate V100 of 100% while minimizing dose to urethra and rectum. All plans met the objective of achieving prostate V100 of 100%. Combined results for all plans show statistically significant improvements in all assessed dosimetric variables for urethra (Umax, Umean, D30, D5) and rectum (Rmax, Rmean, RV100) when using variable spacing. The dose reductions for mean and maximum urethra dose using variable spacing had p values of 0.011 and 0.024 with (103)Pd, and 0.007 and 0.029 with (125)I plans. Similarly dose reductions for mean and maximum rectal dose using variable spacing had p values of 0.007 and 0.052 with (103)Pd, and 0.012 and 0.037 with (125)I plans. The variable needle spacing achievable by the use of robotics in prostate brachytherapy allows for reductions in both urethral and rectal planned doses while maintaining prostate dose coverage. Such dosimetric advantages have the potential in translating to significant clinical benefits with the use of robotic brachytherapy.

Dosimetric comparison of standard three-dimensional conformal radiotherapy followed by intensity-modulated radiotherapy boost schedule (sequential IMRT plan) with simultaneous integrated boost-IMRT (SIB IMRT) treatment plan in patients with localized carcinoma prostate.

PubMed

Bansal, A; Kapoor, R; Singh, S K; Kumar, N; Oinam, A S; Sharma, S C

2012-07-01

DOSIMETERIC AND RADIOBIOLOGICAL COMPARISON OF TWO RADIATION SCHEDULES IN LOCALIZED CARCINOMA PROSTATE: Standard Three-Dimensional Conformal Radiotherapy (3DCRT) followed by Intensity Modulated Radiotherapy (IMRT) boost (sequential-IMRT) with Simultaneous Integrated Boost IMRT (SIB-IMRT). Thirty patients were enrolled. In all, the target consisted of PTV P + SV (Prostate and seminal vesicles) and PTV LN (lymph nodes) where PTV refers to planning target volume and the critical structures included: bladder, rectum and small bowel. All patients were treated with sequential-IMRT plan, but for dosimetric comparison, SIB-IMRT plan was also created. The prescription dose to PTV P + SV was 74 Gy in both strategies but with different dose per fraction, however, the dose to PTV LN was 50 Gy delivered in 25 fractions over 5 weeks for sequential-IMRT and 54 Gy delivered in 27 fractions over 5.5 weeks for SIB-IMRT. The treatment plans were compared in terms of dose-volume histograms. Also, Tumor Control Probability (TCP) and Normal Tissue Complication Probability (NTCP) obtained with the two plans were compared. The volume of rectum receiving 70 Gy or more (V > 70 Gy) was reduced to 18.23% with SIB-IMRT from 22.81% with sequential-IMRT. SIB-IMRT reduced the mean doses to both bladder and rectum by 13% and 17%, respectively, as compared to sequential-IMRT. NTCP of 0.86 ± 0.75% and 0.01 ± 0.02% for the bladder, 5.87 ± 2.58% and 4.31 ± 2.61% for the rectum and 8.83 ± 7.08% and 8.25 ± 7.98% for the bowel was seen with sequential-IMRT and SIB-IMRT plans respectively. For equal PTV coverage, SIB-IMRT markedly reduced doses to critical structures, therefore should be considered as the strategy for dose escalation. SIB-IMRT achieves lesser NTCP than sequential-IMRT.

In vivo diode dosimetry vs. computerized tomography and digitally reconstructed radiographs for critical organ dose calculation in high-dose-rate brachytherapy of cervical cancer.

PubMed

Hassouna, Ashraf H; Bahadur, Yasir A; Constantinescu, Camelia; El Sayed, Mohamed E; Naseem, Hussain; Naga, Adly F

2011-01-01

To investigate the correlation between the dose predicted by the treatment planning system using digitally reconstructed radiographs or three-dimensional (3D)-reconstructed CT images and the dose measured by semiconductor detectors, under clinical conditions of high-dose-rate brachytherapy of the cervix uteri. Thirty-two intracavitary brachytherapy applications were performed for 12 patients with cancer of the cervix uteri. The prescribed dose to Point A was 7 Gy. Dose was calculated for both International Commissioning on Radiation Units and Measurements (ICRU) bladder and rectal points based on digitally reconstructed radiographs and for 3D CT images-based volumetric calculation of the bladder and rectum. In vivo diode dosimetry was performed for the bladder and rectum. The ICRU reference point and the volumes of 1, 2, and 5cm(3) received 3.6±0.9, 5.6±2.0, 5.1±1.7, 4.3±1.4 and 5.0±1.2, 5.3±1.3, 4.9±1.1, and 4.2±0.9 Gy for the bladder and rectum, respectively. The ratio of the 1cm(3) and the ICRU reference point dose to the diode dose was 1.8±0.7 and 1.2±0.5 for the bladder and 1.9±0.6 and 1.7±0.5 for the rectum, respectively. 3D image-based dose calculation is the most accurate and reliable method to evaluate the dose given to critical organs. In vivo diode dosimetry is an important method of quality assurance, but clinical decisions should be made based on 3D-reconstructed CT image calculations. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

The effect of anterior proton beams in the setting of a prostate-rectum spacer

PubMed Central

Christodouleas, John P.; Tang, Shikui; Susil, Robert C.; McNutt, Todd R.; Song, Danny Y.; Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha; DeWeese, Theodore L.; Lu, Hsiao-Ming; Both, Stefan

2014-01-01

Studies suggest that anterior beams with in vivo range verification would improve rectal dosimetry in proton therapy for prostate cancer. We investigated whether prostate-rectum spacers would enhance or diminish the benefits of anterior proton beams in these treatments. Twenty milliliters of hydrogel was injected between the prostate and rectum of a cadaver using a transperineal approach. Computed tomography (CT) and magnetic resonance (MR) images were used to generate 7 uniform scanning (US) and 7 single-field uniform dose pencil-beam scanning (PBS) plans with different beam arrangements. Pearson correlations were calculated between rectal, bladder, and femoral head dosimetric outcomes and beam arrangement anterior scores, which characterize the degree to which dose is delivered anteriorly. The overall quality of each plan was compared using a virtual dose-escalation study. For US plans, rectal mean dose was inversely correlated with anterior score, but for PBS plans there was no association between rectal mean dose and anterior score. For both US and PBS plans, full bladder and empty bladder mean doses were correlated with anterior scores. For both US and PBS plans, femoral head mean doses were inversely correlated with anterior score. For US plans and a full bladder, 4 beam arrangements that included an anterior beam tied for the highest maximum prescription dose (MPD). For US plans and an empty bladder, the arrangement with 1 anterior and 2 anterior oblique beams achieved the highest MPD in the virtual dose-escalation study. The dose-escalation study did not differentiate beam arrangements for PBS. All arrangements in the dose-escalation study were limited by bladder constraints except for the arrangement with 2 posterior oblique beams. The benefits of anterior proton beams in the setting of prostate-rectum spacers appear to be proton modality dependent and may not extend to PBS. PMID:23578497

Culture-Independent Evaluation of the Appendix and Rectum Microbiomes in Children with and without Appendicitis

PubMed Central

Davenport, Katherine P.; Fraser, Claire M.; Sandler, Anthony D.; Zeichner, Steven L.

2014-01-01

Purpose The function of the appendix is largely unknown, but its microbiota likely contributes to function. Alterations in microbiota may contribute to appendicitis, but conventional culture studies have not yielded conclusive information. We conducted a pilot, culture-independent 16S rRNA-based microbiota study of paired appendix and rectal samples. Methods We collected appendix and rectal swabs from 21 children undergoing appendectomy, six with normal appendices and fifteen with appendicitis (nine perforated). After DNA extraction, we amplified and sequenced 16S rRNA genes and analyzed sequences using CLoVR. We identified organisms differing in relative abundance using ANOVA (p<0.05) by location (appendix vs. rectum), disease (appendicitis vs. normal), and disease severity (perforated vs. non-perforated). Results We identified 290 taxa in the study's samples. Three taxa were significantly increased in normal appendices vs. normal rectal samples: Fusibacter (p = 0.009), Selenomonas (p = 0.026), and Peptostreptococcus (p = 0.049). Five taxa were increased in abundance in normal vs. diseased appendices: Paenibacillaceae (p = 0.005), Acidobacteriaceae GP4 (p = 0.019), Pseudonocardinae (p = 0.019), Bergeyella (p = 0.019) and Rhizobium (p = 0.045). Twelve taxa were increased in the appendices of appendicitis patients vs. normal appendix: Peptostreptococcus (p = 0.0003), Bilophila (p = 0.0004), Bulleidia (p = 0.012), Fusobacterium (p = 0.018), Parvimonas (p = 0.003), Mogibacterium (p = 0.012), Aminobacterium (p = 0.019), Proteus (p = 0.028), Actinomycineae (p = 0.028), Anaerovorax (p = 0.041), Anaerofilum (p = 0.045), Porphyromonas (p = 0.010). Five taxa were increased in appendices in patients with perforated vs. nonperforated appendicitis: Bulleidia (p = 0.004), Fusibacter (p = 0.005), Prevotella (p = 0.021), Porphyromonas (p = 0.030), Dialister (p = 0.035). Three taxa were increased in rectum samples of patients with appendicitis compared to the normal patients: Bulleidia (p = 0.034), Dialister (p = 0.003), and Porphyromonas (p = 0.026). Conclusion Specific taxa are more abundant in normal appendices compared to the rectum, suggesting that a distinctive appendix microbiota exists. Taxa with altered abundance in diseased and severely diseased (perforated) samples may contribute to appendicitis pathogenesis, and may provide microbial signatures in the rectum useful for guiding both treatment and diagnosis of appendicitis. PMID:24759879

Image-Based 3D Treatment Planning for Vaginal Cylinder Brachytherapy: Dosimetric Effects of Bladder Filling on Organs at Risk

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hung, Jennifer; Shen Sui; De Los Santos, Jennifer F.

2012-07-01

Purpose: To investigate the dosimetric effects of bladder filling on organs at risk (OARs) using three-dimensional image-based treatment planning for vaginal cylinder brachytherapy. Methods and Materials: Twelve patients with endometrial or cervical cancer underwent postoperative high-dose rate vaginal cylinder brachytherapy. For three-dimensional planning, patients were simulated by computed tomography with an indwelling catheter in place (empty bladder) and with 180 mL of sterile water instilled into the bladder (full bladder). The bladder, rectum, sigmoid, and small bowel (OARs) were contoured, and a prescription dose was generated for 10 to 35 Gy in 2 to 5 fractions at the surface ormore » at 5 mm depth. For each OAR, the volume dose was defined by use of two different criteria: the minimum dose value in a 2.0-cc volume receiving the highest dose (D{sub 2cc}) and the dose received by 50% of the OAR volume (D{sub 50%}). International Commission on Radiation Units and Measurements (ICRU) bladder and rectum point doses were calculated for comparison. The cylinder-to-bowel distance was measured using the shortest distance from the cylinder apex to the contoured sigmoid or small bowel. Statistical analyses were performed with paired t tests. Results: Mean bladder and rectum D{sub 2cc} values were lower than their respective ICRU doses. However, differences between D{sub 2cc} and ICRU doses were small. Empty vs. full bladder did not significantly affect the mean cylinder-to-bowel distance (0.72 vs. 0.92 cm, p = 0.08). In contrast, bladder distention had appreciable effects on bladder and small bowel volume dosimetry. With a full bladder, the mean small bowel D{sub 2cc} significantly decreased from 677 to 408 cGy (p = 0.004); the mean bladder D{sub 2cc} did not increase significantly (1,179 cGy vs. 1,246 cGy, p = 0.11). Bladder distention decreased the mean D{sub 50%} for both the bladder (441 vs. 279 cGy, p = 0.001) and the small bowel (168 vs. 132 cGy, p = 0.001). Rectum and sigmoid volume doses were not affected by bladder filling. Conclusions: In high-dose rate vaginal cylinder brachytherapy, treatment with a distended bladder preferentially reduces high dose to the small bowel around the vaginal cuff without a significant change in dose to the bladder, rectum, or sigmoid.« less

Dose constraints in the rectum and bladder following carbon-ion radiotherapy for uterus carcinoma: a retrospective pooled analysis.

PubMed

Okonogi, Noriyuki; Fukahori, Mai; Wakatsuki, Masaru; Ohkubo, Yu; Kato, Shingo; Miyasaka, Yuhei; Tsuji, Hiroshi; Nakano, Takashi; Kamada, Tadashi

2018-06-25

Carbon-ion radiotherapy (C-ion RT) provides better dose distribution in cancer treatment compared to photons. Additionally, carbon-ion beams provide a higher biological effectiveness, and thus a higher tumor control probability. However, information regarding the dose constraints for organs at risk in C-ion RT is limited. This study aimed to determine the predictive factors for late morbidities in the rectum and bladder after carbon-ion C-ion RT for uterus carcinomas. Between June 1995 and January 2010, 134 patients with uterus carcinomas were treated with C-ion RT with curative intent; prescription doses of 52.8-74.4 Gy (relative biological effectiveness) were delivered in 20-24 fractions. Of these patients, 132 who were followed up for > 6 months were analyzed. We separated the data in two subgroups, a 24 fractions group and a 20 fractions group. Late morbidities, proctitis, and cystitis were assessed according to the Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer criteria. The correlations of clinical and dosimetric parameters, V10-V60, D 5cc , D 2cc , and Dmax, with the incidence of ≥grade 1 morbidities were retrospectively analyzed. In the 24 fractions group, the 3-year actuarial occurrence rates of ≥grade 1 rectal and bladder morbidities were 64 and 9%, respectively. In addition, in the 20 fractions group, the 3-year actuarial occurrence rates of ≥grade 1 rectal and bladder morbidities were 32 and 19%, respectively. Regarding the dose-volume histogram data on the rectum, the D 5cc and D 2cc were significantly higher in patients with ≥grade 1 proctitis than in those without morbidity. In addition, the D 5cc for the bladder was significantly higher in patients with ≥grade 1 cystitis than in those without morbidity. Results of univariate analyses showed that D 2cc of the rectum was correlated with the development of ≥grade 1 late proctitis. Moreover, D 5cc of the bladder was correlated with the development of ≥grade 1 late cystitis. The present study identified the dose-volume relationships in C-ion RT regarding the occurrence of late morbidities in the rectum and bladder. Assessment of the factors discussed herein would be beneficial in preventing late morbidities after C-ion RT for pelvic malignancies. Retrospectively registered ( NIRS: 16-040 ).

Comparison of different contouring definitions of the rectum as organ at risk (OAR) and dose-volume parameters predicting rectal inflammation in radiotherapy of prostate cancer: which definition to use?

PubMed

Nitsche, Mirko; Brannath, Werner; Brückner, Matthias; Wagner, Dirk; Kaltenborn, Alexander; Temme, Nils; Hermann, Robert M

2017-02-01

The objective of this retrospective planning study was to find a contouring definition for the rectum as an organ at risk (OAR) in curative three-dimensional external beam radiotherapy (EBRT) for prostate cancer (PCa) with a predictive correlation between the dose-volume histogram (DVH) and rectal toxicity. In a pre-study, the planning CT scans of 23 patients with PCa receiving definitive EBRT were analyzed. The rectum was contoured according to 13 different definitions, and the dose distribution was correlated with the respective rectal volumes by generating DVH curves. Three definitions were identified to represent the most distinct differences in the shapes of the DVH curves: one anatomical definition recommended by the Radiation Therapy Oncology Group (RTOG) and two functional definitions based on the target volume. In the main study, the correlation between different relative DVH parameters derived from these three contouring definitions and the occurrence of rectal toxicity during and after EBRT was studied in two consecutive collectives. The first cohort consisted of 97 patients receiving primary curative EBRT and the second cohort consisted of 66 patients treated for biochemical recurrence after prostatectomy. Rectal toxicity was investigated by clinical investigation and scored according to the Common Terminology Criteria for Adverse Events. Candidate parameters were the volume of the rectum, mean dose, maximal dose, volume receiving at least 60 Gy (V 60 ), area under the DVH curve up to 25 Gy and area under the DVH curve up to 75 Gy in dependence of each chosen rectum definition. Multivariable logistic regression considered other clinical factors such as pelvine lymphatics vs local target volume, diabetes, prior rectal surgery, anticoagulation or haemorrhoids too. In Cohort 1 (primary EBRT), the mean rectal volumes for definitions "RTOG", planning target volume "(PTV)-based" and "PTV-linked" were 100 cm 3 [standard deviation (SD) 43 cm 3 ], 60 cm 3 (SD 26 cm 3 ) and 74 cm 3 (SD 31 cm 3 ), respectively (p < 0.01; analysis of variance). The mean rectal doses according to these definitions were 35 Gy (SD 8 Gy), 48 Gy (SD 4 Gy) and 44 Gy (SD 5 Gy) (p < 0.01). In Cohort 2 (salvage EBRT), the mean rectal volumes were 114 cm 3 (SD 47 cm 3 ), 64 cm 3 (SD 26 cm 3 ) and 81 cm 3 (SD 30 cm 3 ) (p < 0.01) and the mean doses received by the rectum were 36 Gy (SD 8 Gy), 49 Gy (SD 5 Gy) and 44 Gy (SD 5 Gy) (p < 0.01). Acute or subacute rectal inflammation occurred in 69 (71.9%) patients in Cohort 1 and in 43 (70.5%) in Cohort 2. We did not find a correlation between all investigated DVH parameters and rectal toxicity, irrespective of the investigated definition. By adding additional variables in multivariate analysis, the predictive ability was substantially improved. Still, there was essentially no difference in the probability of predicting rectal inflammation occurrence between the tested contouring definitions. The RTOG anatomy-based recommendations are questionable in comparison with functional definitions, as they result in higher variances in several relative DVH parameters. Moreover, the anatomy-based definition is no better and no worse in the predictive value concerning clinical end points. Advances in knowledge: Functional definitions for the rectum as OAR are easier to apply, faster to contour, have smaller variances and do not offer less information than the anatomy-based RTOG definition.

Rectal biopsy

MedlinePlus

... biopsy; Amyloidosis - rectal biopsy; Crohn disease - rectal biopsy; Colorectal cancer - biopsy; Hirschsprung disease - rectal biopsy ... abnormal conditions of the rectum, such as: Abscesses Colorectal ... Inflammation Tumors Amyloidosis Crohn disease Hirschsprung ...

Strangulation of giant rectal prolapse.

PubMed

El Moussaoui, Imad; Limbga, Augustin; Dika, Manke; Mehdi, Abdelilah

2018-01-01

Introduction Rectal prolapse is the complete protrusion of the rectum through the anal canal, incarceration rarely complicates rectal prolapse. Even more rarely, it becomes strangulated and gangrenous, necessitating emergency surgery. Case presentation We present the first reported case of strangulated acute rectal prolapse as the first manifestation of rectal prolapse. The patient was a 26-year-old man who presented with a 20×6 cm semi-spherical mass extra-anally. Rectosigmoidectomy with sacral rectopexy was performed, resecting 20 cm of the incarcerated rectum and sigmoid colon. The postoperative course was uneventful with a good final result after colostomy closure and continuity restoration. Conclusion The successful treatment of this patient illustrates the value of surgery in this difficult and unusual case scenario of rectal incarceration.

Black Psyllium

MedlinePlus

... in the skin around the anus (anal fissures), surgery on the rectum, and pregnancy. It is also used for diarrhea, dysentery, irritable bowel syndrome (IBS), reducing high cholesterol, and treating cancer.

Immunoscore in Rectal Cancer

ClinicalTrials.gov

2017-06-13

Cancer of the Rectum; Neoplasms, Rectal; Rectal Cancer; Rectal Tumors; Rectal Adenocarcinoma; Melanoma; Breast Cancer; Renal Cell Cancer; Lung Cancer; Bladder Cancer; Head and Neck Cancer; Ovarian Cancer; Thyroid Cancer

Improved probe for rectal-cancer detection

NASA Technical Reports Server (NTRS)

Frazer, R. E.

1979-01-01

Modified protosigmoidoscope, with third partially mirrored lens, provides lateral as well as forward vision for thorough examination of patients for malignant or premalignant lesions of colon and rectum.

[Analysis of histoprognostic factors for the non metastatic rectal cancer in a west Algerian series of 58 cases].

PubMed

Mesli, Smain Nabil; Regagba, Derbali; Tidjane, Anisse; Benkalfat, Mokhtar; Abi-Ayad, Chakib

2016-01-01

The aim of our study was to analyze histoprognostic factors in patients with non-metastatic rectal cancer operated at the division of surgery "A" in Tlemcen, west Algeria, over a period of six years. Retrospective study of 58 patients with rectal adenocarcinoma. Evaluation criterion was survival. Parameters studied were sex, age, tumor stage, tumor recurrence. The average age was 58 years, 52% of men and 48% of women, with sex-ratio (1,08). Tumor seat was: middle rectum 41.37%, lower rectum 34.48% and upper rectum 24.13%. Concerning TNM clinical staging, patients were classified as stage I (17.65%), stage II (18.61%), stage III (53.44%) and stage IV (7.84%). Median overall survival was 40 months ±2,937 months. Survival based on tumor staging: stage III and IV had a lower 3 years survival rate (19%) versus stage I, II which had a survival rate of 75% (P = 0.000) (95%). Patients with tumor recurrences had a lower 3 years survival rate compared to those who had no tumoral recurrences (30.85% vs 64.30% P = 0.043). In this series, univariate analysis of prognostic factors affecting survival allowed to retain only three factors influencing survival: tumor size, stage and tumor recurrences. In multivariate analysis using Cox's model only one factor was retained: tumor recurrence.

Low abdominoperineal excision rates are associated with high-workload surgeons and lower tumour height. Is further specialization needed?

PubMed

Morris, E J A; Birch, R; West, N P; Finan, P J; Forman, D; Fairley, L; Quirke, P

2011-07-01

Wide variation, independent of disease extent and case mix, has been observed in the rate of use of abdominoperineal excision (APE) for rectal cancer. Previous analyses have, however, been confounded by failure to adjust for the location of the tumour within the rectum. This population-based study sought to examine whether variations in tumour height explained differences in APE use. Information was obtained on all individuals who underwent a major resection for a rectal tumour diagnosed between 1998 and 2005 across the Northern and Yorkshire regions of the UK. Median distances from the dentate line were calculated for all tumours excised by APE and compared with rates of use of APE between specialists and nonspecialist surgeons and across hospital trusts. The completeness of pathological reporting of height of tumour within the rectum was variable. A low rate of APE use was associated with a lower median distance of tumours from the dentate line. Specialist colorectal cancer surgeons performed fewer APEs on patients with a tumour located lower in the rectum than nonspecialist surgeons. Variations in the height of tumour did not explain the variation in APE use. Specialist high-volume surgeons undertook fewer APEs and those they performed were closer to the dentate line than low-volume nonspecialist surgeons. © 2011 The Authors. Colorectal Disease © 2011 The Association of Coloproctology of Great Britain and Ireland.

Near real-time automated dose restoration in IMPT to compensate for daily tissue density variations in prostate cancer

NASA Astrophysics Data System (ADS)

Jagt, Thyrza; Breedveld, Sebastiaan; van de Water, Steven; Heijmen, Ben; Hoogeman, Mischa

2017-06-01

Proton therapy is very sensitive to daily density changes along the pencil beam paths. The purpose of this study is to develop and evaluate an automated method for adaptation of IMPT plans to compensate for these daily tissue density variations. A two-step restoration method for ‘densities-of-the-day’ was created: (1) restoration of spot positions (Bragg peaks) by adapting the energy of each pencil beam to the new water equivalent path length; and (2) re-optimization of pencil beam weights by minimizing the dosimetric difference with the planned dose distribution, using a fast and exact quadratic solver. The method was developed and evaluated using 8-10 repeat CT scans of 10 prostate cancer patients. Experiments demonstrated that giving a high weight to the PTV in the re-optimization resulted in clinically acceptable restorations. For all scans we obtained V 95%  ⩾  98% and V 107%  ⩽  2%. For the bladder, the differences between the restored and the intended treatment plan were below  +2 Gy and  +2%-point. The rectum differences were below  +2 Gy and  +2%-point for 90% of the scans. In the remaining scans the rectum was filled with air, which partly overlapped with the PTV. The air cavity distorted the Bragg peak resulting in less favorable rectum doses.

Using GIS for spatial analysis of rectal lesions in the human body.

PubMed

Garb, Jane L; Ganai, Sabha; Skinner, Ric; Boyd, Christopher S; Wait, Richard B

2007-03-15

Geographic Information Systems (GIS) have been used in a wide variety of applications to integrate data and explore the spatial relationship of geographic features. Traditionally this has referred to features on the surface of the earth. However, it is possible to apply GIS in medicine, at the scale of the human body, to visualize and analyze anatomic and clinical features. In the present study we used GIS to examine the findings of transanal endoscopic microsurgery (TEM), a minimally-invasive procedure to locate and remove both benign and cancerous lesions of the rectum. Our purpose was to determine whether anatomic features of the human rectum and clinical findings at the time of surgery could be rendered in a GIS and spatially analyzed for their relationship to clinical outcomes. Maps of rectal topology were developed in two and three dimensions. These maps highlight anatomic features of the rectum and the location of lesions found on TEM. Spatial analysis demonstrated a significant relationship between anatomic location of the lesion and procedural failure. This study demonstrates the feasibility of rendering anatomical locations and clinical events in a GIS and its value in clinical research. This allows the visualization and spatial analysis of clinical and pathologic features, increasing our awareness of the relationship between anatomic features and clinical outcomes as well as enhancing our understanding and management of this disease process.

Perineal colostomy: an alternative to avoid permanent abdominal colostomy: operative technique, results and reflection

PubMed Central

da SILVA, Alcino Lázaro; HAYCK, Johnny; DEOTI, Beatriz

2014-01-01

Background The most common injury to indicate definitive stoma is rectal cancer. Despite advances in surgical treatment, the abdominoperineal resection is still the most effective operation in radical treatment of malignancies of the distal rectum invading the sphincter and anal canal. Even with all the effort that surgeons have to preserve anal sphincters, abdominoperineal amputation is still indicated, and a definitive abdominal colostomy is necessary. This surgery requires patients to live with a definitive abdominal colostomy, which is a condition that modify body image, is not without morbidity and has great impact on the quality of life. Aim To evaluate the technique of abdominoperineal amputation with perineal colostomy with irrigation as an alternative to permanent abdominal colostomy. Method Retrospective analysis of medical records of 55 patients underwent abdominoperineal resection of the rectum with perineal colostomy in the period 1989-2010. Results The mean age was 58 years, 40 % men and 60 % women. In 94.5% of patients the indication for surgery was for cancer of the rectum. In some patients were made three valves, other two valves and in the remaining no valve at all. Complications were: mucosal prolapse, necrosis of the lowered segment and stenosis. Conclusion The abdominoperineal amputation with perineal colostomy is a good therapeutic option in the armamentarium of the surgical treatment of rectal cancer. PMID:25626931

Using GIS for spatial analysis of rectal lesions in the human body

PubMed Central

Garb, Jane L; Ganai, Sabha; Skinner, Ric; Boyd, Christopher S; Wait, Richard B

2007-01-01

Background Geographic Information Systems (GIS) have been used in a wide variety of applications to integrate data and explore the spatial relationship of geographic features. Traditionally this has referred to features on the surface of the earth. However, it is possible to apply GIS in medicine, at the scale of the human body, to visualize and analyze anatomic and clinical features. In the present study we used GIS to examine the findings of transanal endoscopic microsurgery (TEM), a minimally-invasive procedure to locate and remove both benign and cancerous lesions of the rectum. Our purpose was to determine whether anatomic features of the human rectum and clinical findings at the time of surgery could be rendered in a GIS and spatially analyzed for their relationship to clinical outcomes. Results Maps of rectal topology were developed in two and three dimensions. These maps highlight anatomic features of the rectum and the location of lesions found on TEM. Spatial analysis demonstrated a significant relationship between anatomic location of the lesion and procedural failure. Conclusion This study demonstrates the feasibility of rendering anatomical locations and clinical events in a GIS and its value in clinical research. This allows the visualization and spatial analysis of clinical and pathologic features, increasing our awareness of the relationship between anatomic features and clinical outcomes as well as enhancing our understanding and management of this disease process. PMID:17362510

Interindividual registration and dose mapping for voxelwise population analysis of rectal toxicity in prostate cancer radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dréan, Gaël; Acosta, Oscar, E-mail: Oscar.Acosta@univ-rennes1.fr; Simon, Antoine

2016-06-15

Purpose: Recent studies revealed a trend toward voxelwise population analysis in order to understand the local dose/toxicity relationships in prostate cancer radiotherapy. Such approaches require, however, an accurate interindividual mapping of the anatomies and 3D dose distributions toward a common coordinate system. This step is challenging due to the high interindividual variability. In this paper, the authors propose a method designed for interindividual nonrigid registration of the rectum and dose mapping for population analysis. Methods: The method is based on the computation of a normalized structural description of the rectum using a Laplacian-based model. This description takes advantage of themore » tubular structure of the rectum and its centerline to be embedded in a nonrigid registration-based scheme. The performances of the method were evaluated on 30 individuals treated for prostate cancer in a leave-one-out cross validation. Results: Performance was measured using classical metrics (Dice score and Hausdorff distance), along with new metrics devised to better assess dose mapping in relation with structural deformation (dose-organ overlap). Considering these scores, the proposed method outperforms intensity-based and distance maps-based registration methods. Conclusions: The proposed method allows for accurately mapping interindividual 3D dose distributions toward a single anatomical template, opening the way for further voxelwise statistical analysis.« less

Optical coherence tomography in guided surgery of GI cancer

NASA Astrophysics Data System (ADS)

Zagaynova, Elena V.; Abelevich, Alexander I.; Zagaynov, Vladimir E.; Gladkova, Natalia D.; Denisenko, Arkady N.; Feldchtein, Felix I.; Snopova, Ludmila B.; Kutis, Irina S.

2005-04-01

Optical Coherence Tomography (OCT) is a new high spatial resolution, real-time optical imaging modality, known from prior pilot studies for its high sensitivity to invasive cancer. We reported our results in an OCT feasibility study for accurate determination of the proximal border for esophageal carcinoma and the distal border for rectal carcinoma. The OCT study enrolled 19 patients with rectal adenocarcinoma and 24 patients with distal esophageal carcinoma (14 squamous cell carcinomas, 10 adenocarcinomas). During pre-surgery planning endoscopy we performed in vivo OCT imaging of the tumor border at four dial clock axes (12, 3, 6 and 9 o"clock). The OCT border then was marked by an electrocoagulator, or by a methylene blue tattoo. A cold biopsy (from the esophagus) was performed at visual and OCT borders and compared with visual and OCT readings. 27 post-surgery excised specimens were analyzed. OCT borders matched the histopathology in 94% cases in the rectum and 83.3% in the esophagus. In the cases of a mismatch between the OCT and histology borders, a deep tumor invasion occurred in the muscle layer (esophagus, rectum). Because of its high sensitivity to mucosal cancer, OCT can be used for pre-surgery planning and surgery guidance of the proximal border for esophageal carcinoma and the distal border for rectal carcinoma. However, deep invasion in the rectum or esophageal wall has to be controlled by alternative diagnostic modalities.

Evaluation of plasma diazepam and nordiazepam concentrations following administration of diazepam intravenously or via suppository per rectum in dogs.

PubMed

Probst, Curtis W; Thomas, William B; Moyers, Tamberlyn D; Martin, Tomas; Cox, Sherry

2013-04-01

To evaluate the pharmacokinetics of diazepam administered per rectum via compounded (ie, not commercially available) suppositories and determine whether a dose of 2 mg/kg in this formulation would result in plasma concentrations shown to be effective for control of status epilepticus or cluster seizures (ie, 150 to 300 ng/mL) in dogs within a clinically useful interval (10 to 15 minutes). 6 healthy mixed-breed dogs. Dogs were randomly assigned to 2 groups of 3 dogs each in a crossover-design study. Diazepam (2 mg/kg) was administered IV or via suppository per rectum, and blood samples were collected at predetermined time points. Following a 6- or 7-day washout period, each group received the alternate treatment. Plasma concentrations of diazepam and nordiazepam were analyzed via reversed phase high-performance liquid chromatography. Plasma concentrations of diazepam and nordiazepam exceeded the targeted range ≤ 3 minutes after IV administration in all dogs. After suppository administration, targeted concentrations of diazepam were not detected in any dogs, and targeted concentrations of nordiazepam were detected after 90 minutes (n = 2 dogs) or 120 minutes (3) or were not achieved (1). On the basis of these results, administration of 2 mg of diazepam/kg via the compounded suppositories used in the present study cannot be recommended for emergency treatment of seizures in dogs.

Loss of visceral pain following colorectal distension in an endothelin-3 deficient mouse model of Hirschsprung's disease

PubMed Central

Zagorodnyuk, Vladimir P; Kyloh, Melinda; Nicholas, Sarah; Peiris, Heshan; Brookes, Simon J; Chen, Bao Nan; Spencer, Nick J

2011-01-01

Abstract Endothelin peptides and their endogenous receptors play a major role in nociception in a variety of different organs. They also play an essential role in the development of the enteric nervous system. Mice with deletions of the endothelin-3 gene (lethal spotted mice, ls/ls) develop congenital aganglionosis. However, little is known about how nociception might be affected in the aganglionic rectum of mice deficient in endothelin-3. In this study we investigated changes in spinal afferent innervation and visceral pain transmission from the aganglionic rectum in ls/ls mice. Electromyogram recordings from anaesthetized ls/ls mice revealed a deficit in visceromotor responses arising from the aganglionic colorectum in response to noxious colorectal distension. Loss of visceromotor responses (VMRs) in ls/ls mice was selective, as no reduction in VMRs was detected after stimulation of the bladder or somatic organs. Calcitonin gene related peptide (CGRP) immunoreactivity, retrograde neuronal tracing and extracellular afferent recordings from the aganglionic rectum revealed decreased colorectal spinal innervation, combined with a reduction in mechanosensitivity of rectal afferents. The sensory defect in ls/ls mice is primarily associated with changes in low threshold wide dynamic range rectal afferents. In conclusion, disruption of endothelin 3 gene expression not only affects development and function of the enteric nervous system, but also specific classes of spinal rectal mechanoreceptors, which are required for visceral nociception from the colorectum. PMID:21320883

Dialysis of the rectum for sampling drug concentrations in the luminal extracellular fluid of the gut: technique and precision.

PubMed

Egan, L J; Sandborn, W J; Mays, D C; Tremaine, W J; Lipsky, J J

1998-07-01

It is useful to measure the luminal concentration of drugs which act in the gut. Dialysis of the rectum has not previously been used or validated for this purpose. To determine the precision of rectal dialysis for measuring rectal drug concentrations. To establish the duration of dialysis required to approach equilibrium, the rate of methotrexate diffusion into dialysis bags was first determined in vitro. The precision of rectal dialysis for sampling the methotrexate concentration of colonic lumen extracellular fluid was determined in seven subjects who underwent two consecutive dialysis procedures. Subjects treated with subcutaneous methotrexate for refractory inflammatory bowel disease were studied. Methotrexate crossed the dialysis membrane by a first-order process, and after a 2 h in vitro dialysis, equilibration was 74 +/- 2% (mean +/- s.d.) complete. Rectal dialysis was well tolerated by all subjects. The mean +/- s.e. methotrexate concentration of 3.6 +/- 1.1 nmol/L in the first dialysate was not significantly different from 3.6 +/- 0.9 nmol/L in the second dialysate. P = 0.99 (paired two-tailed t-test). Similar precision was obtained for an endogenous molecule, potassium, secreted by the rectal mucosa. Dialysis of the rectum is a well tolerated and precise technique for sampling the colonic lumen extracellular fluid for quantitative analyses of exogenous and endogenous substances.

Irinotecan-encapsulated double-reverse thermosensitive nanocarrier system for rectal administration.

PubMed

Din, Fakhar Ud; Choi, Ju Yeon; Kim, Dong Wuk; Mustapha, Omer; Kim, Dong Shik; Thapa, Raj Kumar; Ku, Sae Kwang; Youn, Yu Seok; Oh, Kyung Taek; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

2017-11-01

Intravenously administered for the treatment of rectum cancer, irinotecan produces severe side effects due to very high plasma concentrations. A novel irinotecan-encapsulated double reverse thermosensitive nanocarrier system (DRTN) for rectal administration was developed as an alternative. The DRTN was fabricated by dispersing the thermosensitive irinotecan-encapsulated solid lipid nanoparticles (SLN) in the thermosensitive poloxamer solution. Its gel properties, pharmacokinetics, morphology, anticancer activity and immunohistopathology were assessed after its rectal administration to rats and tumor-bearing mice. In the DRTN, the solid form of the SLN and the liquid form of the poloxamer solution persisted at 25 °C; the former melted to liquid, and the latter altered to gel at 36.5 °C. The DRTN was easily administered to the anus, gelling rapidly and strongly after rectal administration. Compared to the conventional hydrogel and intravenously administered solution, it retarded dissolution and initial plasma concentration. The DRTN gave sustained release and nearly constant plasma concentrations of irinotecan at 1-3 h in rats, resulting in improved anticancer activity. It induced no damage to the rat rectum and no body weight loss in tumor-bearing mice. Thus, this irinotecan-encapsulated DRTN associated with a reduced burst effect, lack of toxicity and excellent antitumor efficacy would be strongly recommended as a rectal pharmaceutical product alternative to commercial intravenous injection in the treatment of rectum and colon cancer.

Evaluation of pelvic posterior exenteration in the management of advanced-stage ovarian cancer.

PubMed

Tixier, Hervé; Fraisse, Jean; Chauffert, Bruno; Mayer, Françoise; Causeret, Sylvain; Loustalot, Catherine; Deville, Coralie; Bonnetain, Franck; Sagot, Paul; Douvier, Serge; Cuisenier, Jean

2010-03-01

The main aim of this study was to show the interest of pelvic posterior exenteration to obtain complete resection of the tumor in case of invasion of the rectum by contiguity in advanced-stage ovarian cancer. The secondary aim was to determine the morbidity of this surgery. It is a multicentric, retrospective study of a series of 41 patients, who underwent posterior pelvectomy for advanced-stage ovarian cancer, over a period of 18 years, from July 1989 to July 2007. The surgery resulted in macroscopically complete resection in 19 patients (46.34%), a residual tumor <2 cm in 19 patients (46.34%) and >2 cm in 3 patients (7.32%). In 34 patients (34/41), digestive continuity with satisfactory anal sphincter function was restored immediately or in the short term. The mean delay to the start of complementary treatment was 36 days. Median overall survival was 33 months. The main aim of surgery for ovarian peritoneal carcinomatosis is to obtain a complete resection. In the case of direct invasion of the rectum by contiguity, when there is no cleavage plane between the uterus and the rectum, pelvic posterior exenteration is an effective method to achieve this objective. Morbidity is relatively high, but acceptable given the poor prognosis of this disease, the improved survival after surgery, and improvements in post-operative quality of life and functions.

Pinworms

MedlinePlus

Pinworms are small parasites that can live in the colon and rectum. You get them when you ... inside your intestines. While you sleep, the female pinworms leave the intestines through the anus and lay ...

Hemorrhoids

MedlinePlus

Hemorrhoids are swollen, inflamed veins around the anus or lower rectum. They are either inside the anus ... include pregnancy, aging and chronic constipation or diarrhea. Hemorrhoids are very common in both men and women. ...

Mesalamine

MedlinePlus

... large intestine] and rectum) and also to maintain improvement of ulcerative colitis symptoms. Mesalamine is in a ... medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. ...

Anal fissure

MedlinePlus

... Kliegman RM, Stanton BF, St. Geme JW, Schor NF. Surgical conditions of anus and rectum. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, ...

Colorectal Cancer

MedlinePlus

... rectum are part of the large intestine. Colorectal cancer occurs when tumors form in the lining of ... men and women. The risk of developing colorectal cancer rises after age 50. You're also more ...

Colon diverticula - slideshow

MedlinePlus

... to the rectum. The colon absorbs water from liquid stool that is delivered to it from the small ... and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Medical ...

Endoscopic Mucosectomy in a Child Presenting with Gastric Heterotopia of the Rectum.

PubMed

Soares, Joana; Ferreira, Carla; Marques, Margarida; Corujeira, Susana; Tavares, Marta; Lopes, Joanne; Carneiro, Fátima; Amil Dias, Jorge; Trindade, Eunice

2017-11-01

Gastric mucosal heterotopia has been described in all levels of the gastrointestinal tract. Its occurrence in the rectum is uncommon. We report the case of a 4-year-old boy referred to Pediatric Gastroenterology for intermittent rectal bleeding for the past 2 years. Total ileocolonoscopy revealed a flat, well-circumscribed lesion of 4 cm, with elevated margins, localized at 10 cm from the anal verge. Histologic examination showed typical gastric mucosa of the oxyntic type. Treatment with proton pump inhibitors was started without resolution of the symptoms and, therefore, an endoscopic mucosal resection was performed. Heterotopic gastric mucosa represents a rare cause of rectal bleeding in children and endoscopic evaluation is fundamental for diagnosis. Although not usually performed in pediatric ages, endoscopic mucosectomy allows complete resolution of the problem avoiding surgery.

Rectal volvulus following laparoscopic left hemicolectomy

PubMed Central

Sutton, Paul Anthony; Lee, Han Sian; Din, Islah; Vimalachandran, Dale

2013-01-01

A 60-year-old lady with a history of Dukes B2 (T3N0M0) colorectal cancer presented some 2 years following a laparoscopic left hemicolectomy with a 4-day history of absolute constipation. A plain radiograph demonstrated large bowel obstruction, and subsequent CT of the abdomen showed the level of the obstruction to be at the rectum. Initially the aetiology was believed to be recurrence at the site of the anastomosis; however, subsequent review of the imaging and indeed endoscopic examination of the rectum showed it to be volvulus. This was initially treated with endoscopic decompression and later by the insertion of a flatus tube to good effect. The patient was discharged 3 days later with no recurrence of her symptoms at 2 months. PMID:23608861

Rectal metastasis from breast cancer: an interval of 17 years.

PubMed

Amin, Aliasger A; Reddy, Anil; Jha, Madan; Prasad, Kolanu

2011-05-12

Metastasis to gastrointestinal (GI) tract from breast cancer is rare. Commonly affected organ in GI tract is stomach, followed by colon and then rectum. The authors report a case of a 61-year-old woman who had a mastectomy for lobular carcinoma of the breast 17 years ago and was referred to colorectal clinic with increased frequency of stools. Colonoscopy showed a stricture in the rectum, but biopsy was inconclusive. As she was symptomatic, she had a Hartmann's resection 5 months after she initially presented to the clinic. Histopathology of the resected specimen showed it to be metastasis from lobular carcinoma of the breast. Awareness of potential long delays in the presentation of metastatic breast cancer especially lobular carcinoma helps in the earlier diagnosis and clinical management.

Invasive lobular breast carcinoma metastasising to the rectum.

PubMed

Cherian, Nishant; Qureshi, Nafees Ahmad; Cairncross, Callum; Solkar, Mamoon

2017-08-03

Gastrointestinal (GI) metastasis from a primary breast carcinoma is uncommon, with the rectum being one of the least reported sites in the literature. We report a case of a 79-year-old woman who underwent treatment for an infiltrative lobular carcinoma of the right breast with nodal involvement, and 10 years later developed recurrence in the form of rectal metastasis. Spread to the GI tract is most commonly seen with lobular breast carcinomas. Any patient with a history of breast cancer presenting typically or atypically with abdominal symptoms or altered bowel habit should raise a high index of suspicion for recurrent or metastatic disease. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Possible cost reduction and better surgical results using EEA stapler in tumors of the upper rectum].

PubMed

Coda, A; Ferri, F

1990-01-01

The aim of this work was to compare the relative costs and outcome of the anterior resection of the rectum for upper rectal cancer mechanically or manually performed. Therefore, the last two manual sutures and the first two cases operated using mechanical sutures were taken into account. Patients were homogenous for age, general conditions and cancer stage. Upper rectal location was choosen for the comparison considering the use of stapler not essential in this site. Analysis of the course showed no complications, shorter hospitalization, reduced drug therapy, and fewer diagnostic procedures needed in patients operated on with staplers. Although these data have no statistical rank, better surgical results and remarkable saving in social costs were observed with the use of stapling devices.

[Trans-suture mechanical colorectal anastomosis using a double stapler in the anterior resection of the rectum. Technical note].

PubMed

Saviano, M S; Ricchi, E

1990-04-30

The spread of mechanical staplers now makes it possible to perform anastomoses in anterior resections of the rectum that are easier and safer than manual ones. Certain related problems are well known, particularly in patients with narrow pelvis and, in low anastomoses, the fashioning of the tobacco pouch on the distal rectal stump. The technique of transutural mechanical colorectal anastomosis with circular stapler after closure of the rectal stump with linear stapler is described in detail. Advantages of the technique are: anastomoses that are technically easier and safer because making of the tobacco pouch on the distal rectal stump is avoided; pollution of the operating field is reduced to the minimum; there are no problems related to differences in lumen of the colorectal stumps.

Transanal Total Mesorectal Excision: A Novel Approach to Rectal Surgery

PubMed Central

Suwanabol, Pasithorn A.; Maykel, Justin A.

2017-01-01

Less invasive approaches continue to be explored and refined for diseases of the colon and rectum. The current gold standard for the surgical treatment of rectal cancer, total mesorectal excision (TME), is a technically precise yet demanding procedure with outcomes measured by both oncologic and functional outcomes (including bowel, urinary, and sexual). To date, the minimally invasive approach to rectal cancer has not yet been perfected, leaving ample opportunity for rectal surgeons to innovate. Transanal TME has recently emerged as a safe and effective technique for both benign and malignant diseases of the rectum. While widespread acceptance of this surgical approach remains tempered at this time due to lack of long-term oncologic outcome data, short-term outcomes are promising and there is great excitement surrounding the promise of this technique. PMID:28381943

Laparoscopic intestinal derotation: original technique.

PubMed

Valle, Mario; Federici, Orietta; Tarantino, Enrico; Corona, Francesco; Garofalo, Alfredo

2009-06-01

The intestinal derotation technique, introduced by Cattel and Valdoni 40 years ago, is carried out using a laparoscopic procedure, which is described here for the first time. The method is effective in the treatment of malign lesions of the III and IV duodenum and during laparoscopic subtotal colectomy with anastomosis between the ascending colon and the rectum. Ultimately, the procedure allows for the verticalization of the duodenal C and the anterior positioning of the mesenteric vessels, facilitating biopsy and resection of the III and IV duodenal portions and allowing anastomosis of the ascending rectum, avoiding both subtotal colectomy and the risk of torsion of the right colic loop. Although the procedure calls for extensive experience with advanced video-laparoscopic surgery, it is both feasible and repeatable. In our experience we have observed no mortality or morbidity.

Conservative surgery versus colorectal resection in deep endometriosis infiltrating the rectum: a randomized trial.

PubMed

Roman, Horace; Bubenheim, Michael; Huet, Emmanuel; Bridoux, Valérie; Zacharopoulou, Chrysoula; Daraï, Emile; Collinet, Pierre; Tuech, Jean-Jacques

2018-01-01

Is there a difference in functional outcome between conservative versus radical rectal surgery in patients with large deep endometriosis infiltrating the rectum 2 years postoperatively? No evidence was found that functional outcomes differed when conservative surgery was compared to radical rectal surgery for deeply invasive endometriosis involving the bowel. Adopting a conservative approach to the surgical management of deep endometriosis infiltrating the rectum, by employing shaving or disc excision, appears to yield improved digestive functional outcomes. However, previous comparative studies were not randomized, introducing a possible bias regarding the presumed superiority of conservative techniques due to the inclusion of patients with more severe deep endometriosis who underwent colorectal resection. From March 2011 to August 2013, we performed a 2-arm randomized trial, enroling 60 patients with deep endometriosis infiltrating the rectum up to 15 cm from the anus, measuring more than 20 mm in length, involving at least the muscular layer in depth and up to 50% of rectal circumference. No women were lost to follow-up. Patients were enroled in three French university hospitals and had either conservative surgery, by shaving or disc excision, or radical rectal surgery, by segmental resection. Randomization was performed preoperatively using sequentially numbered, opaque, sealed envelopes, and patients were informed of the results of randomization. The primary endpoint was the proportion of patients experiencing one of the following symptoms: constipation (1 stool/>5 consecutive days), frequent bowel movements (≥3 stools/day), defecation pain, anal incontinence, dysuria or bladder atony requiring self-catheterization 24 months postoperatively. Secondary endpoints were the values of the Visual Analog Scale (VAS), Knowles-Eccersley-Scott-Symptom Questionnaire (KESS), the Gastrointestinal Quality of Life Index (GIQLI), the Wexner scale, the Urinary Symptom Profile (USP) and the Short Form 36 Health Survey (SF36). A total of 60 patients were enroled. Among the 27 patients in the conservative surgery arm, two were converted to segmental resection (7.4%). In each group, 13 presented with at least one functional problem at 24 months after surgery (48.1 versus 39.4%, OR = 0.70, 95% CI 0.22-2.21). The intention-to-treat comparison of the overall scores on KESS, GIQLI, Wexner, USP and SF36 did not reveal significant differences between the two arms. Segmental resection was associated with a significant risk of bowel stenosis. The inclusion of only large infiltrations of the rectum does not allow the extrapolation of conclusions to small nodules of <20 mm in length. The presumption of a 40% difference favourable to conservative surgery in terms of postoperative functional outcomes resulted in a lack of power to demonstrate a difference for the primary endpoint. Conservative surgery is feasible in patients managed for large deep rectal endometriosis. The trial does not show a statistically significant superiority of conservative surgery for mid-term functional digestive and urinary outcomes in this specific population of women with large involvement of the rectum. There is a higher risk of rectal stenosis after segmental resection, requiring additional endoscopic or surgical procedures. This work was supported by a grant from the clinical research programme for hospitals (PHRC) in France. The authors declare no competing interests related to this study. This study is registered with ClinicalTrials.gov, number NCT 01291576. 31 January 2011. 7 March 2011. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Effects of organ motion on proton prostate treatments, as determined from analysis of daily CT imaging for patient positioning.

PubMed

Maeda, Yoshikazu; Sato, Yoshitaka; Shibata, Satoshi; Bou, Sayuri; Yamamoto, Kazutaka; Tamamura, Hiroyasu; Fuwa, Nobukazu; Takamatsu, Shigeyuki; Sasaki, Makoto; Tameshige, Yuji; Kume, Kyo; Minami, Hiroki; Saga, Yusuke; Saito, Makoto

2018-05-01

We quantified interfractional movements of the prostate, seminal vesicles (SVs), and rectum during computed tomography (CT) image-guided proton therapy for prostate cancer and studied the range variation in opposed lateral proton beams. We analyzed 375 sets of daily CT images acquired throughout the proton therapy treatment of ten patients. We analyzed daily movements of the prostate, SVs, and rectum by simulating three image-matching strategies: bone matching, prostate center (PC) matching, and prostate-rectum boundary (PRB) matching. In the PC matching, translational movements of the prostate center were corrected after bone matching. In the PRB matching, we performed PC matching and correction along the anterior-posterior direction to match the boundary between the prostate and the rectum's anterior region. In each strategy, we evaluated systematic errors (Σ) and random errors (σ) by measuring the daily movements of certain points on each anatomic structure. The average positional deviations in millimeter of each point were determined by the Van Herk formula of 2.5Σ + 0.7σ. Using these positional deviations, we created planning target volumes of the prostate and SVs and analyzed the daily variation in the water equivalent length (WEL) from the skin surface to the target along the lateral beam directions using the density converted from the daily CT number. Based on this analysis, we designed prostate cancer treatment planning and evaluated the dose volume histograms (DVHs) for these strategies. The SVs' daily movements showed large variations over the superior-inferior direction, as did the rectum's anterior region. The average positional deviations of the prostate in the anterior, posterior, superior, inferior, and lateral sides (mm) in bone matching, PC matching, and PRB matching were (8.9, 9.8, 7.5, 3.6, 1.6), (5.6, 6.1, 3.5, 4.5, 1.9), and (8.6, 3.2, 3.5, 4.5, 1.9) (mm), respectively. Moreover, the ones of the SV tip were similarly (22.5, 15.5, 11.0, 7.6, 6.0), (11.8, 8.4, 7.8, 5.2, 6.3), and (9.9, 7.5, 7.8, 5.2, 6.3). PRB matching showed the smallest positional deviations at all portions except for the anterior portion of the prostate and was able to markedly reduce the positional deviations at the posterior portion. The averaged WEL variations at the distal and proximal sides of planning target volumes were estimated 7-9 mm and 4-6 mm, respectively, and showed the increasing of a few millimeters in PC and PRB matching compared to bone matching. In the treatment planning simulation, the DVH values of the rectum in PRB matching were reduced compared to those obtained with other matching strategies. The positional deviations for the prostate on the posterior side and the SVs were smaller by PRB matching than the other strategies and effectively reduced the rectal dose. 3D dose calculations indicate that PRB matching with CT image guidance may do a better job relative to other positioning methods to effectively reduce the rectal complications. The WEL variation was quite large, and the appropriate margin (approx. 10 mm) must be adapted to the proton range in an initial planning to maintain the coverage of target volumes throughout entire treatment. © 2018 American Association of Physicists in Medicine.

Rectal prolapse

MedlinePlus

Kliegman RM, Stanton BF, St Geme JW, Schor NF. Surgical conditions of the anus and rectum. In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, ...

Imperforate anus

MedlinePlus

Kliegman RM, Stanton BF, St. Geme JW, Schor NF. Surgical conditions of the anus and rectum. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, ...

GI bleeding - slideshow

MedlinePlus

... this page: //medlineplus.gov/ency/presentations/100162.htm GI bleeding - series—Normal anatomy To use the sharing ... colon, and finally, the rectum and anus. The GI tract is a long, hollow, muscular tube through ...

Total abdominal colectomy

MedlinePlus

... the rectum. This can cause an infection or abscess. Scarring of the connection between the small intestine ... Wechter, MD, FACS, general surgery practice specializing in breast cancer, Virginia Mason Medical Center, Seattle, WA. Also ...

Rectal Prolapse

MedlinePlus

... or robotically, are used in some centers with equivalent success to traditional abdominal procedures. Laparoscopy refers to ... stuck” on the outside) with concerns for a non-viable (or “dead”) rectum, may need to undergo ...

ERCP

MedlinePlus

... dye, or drug used during the procedure Bleeding Hole (perforation) of the bowel Inflammation of the pancreas ( ... or severe bloating Bleeding from the rectum or black stools Fever above 100°F (37.8°C) ...

Ostomy

MedlinePlus

An ostomy is surgery to create an opening (stoma) from an area inside the body to the outside. It ... small intestine, colon, rectum, or bladder. With an ostomy, there must be a new way for wastes ...

Anal fissure - slideshow

MedlinePlus

... this page: //medlineplus.gov/ency/presentations/100154.htm Anal fissure - series—Normal anatomy To use the sharing ... rectum through which passes stool during defecation. The anal sphincter is a critical mechanism for control of ...

Engagement of Patients With Advanced Cancer

ClinicalTrials.gov

2017-05-12

End of Life; Advanced Cancer; Lung Neoplasm; Gastric Cancer; Colon Cancer; Glioblastoma Multiforme; Head and Neck Neoplasms; Rectum Cancer; Melanoma; Kidney Cancer; Prostate Cancer; Testicular Neoplasms; Liver Cancer; Cancer of Unknown Origin

Rectovaginal Fistula

MedlinePlus

... rectovaginal fistula may result from: Injury during childbirth Crohn's disease or other inflammatory bowel disease Radiation treatment or ... the rectum that help you hold in stool. Crohn's disease. The second most common cause of rectovaginal fistulas, ...

Hydrocortisone Rectal

MedlinePlus

Rectal hydrocortisone is used along with other medications to treat proctitis (swelling in the rectum) and ulcerative colitis (a ... and swelling from hemorrhoids and other rectal problems. Hydrocortisone is in a class of medications called corticosteroids. ...

Common symptoms during pregnancy

MedlinePlus

... keep your gums healthy Swelling, Varicose Veins, and Hemorrhoids Swelling in your legs is common. You may ... In your rectum, veins that swell are called hemorrhoids. To reduce swelling: Raise your legs and rest ...

Colon cancer

MedlinePlus

Colorectal cancer; Cancer - colon; Rectal cancer; Cancer - rectum; Adenocarcinoma - colon; Colon - adenocarcinoma; Colon carcinoma ... In the United States, colorectal cancer is one of the leading ... to cancer. Early diagnosis can often lead to a complete cure. ...

Colorectal Cancer

MedlinePlus

... be detected by optical colonoscopy. Virtual colonoscopy uses virtual reality technology to produce three-dimensional images of the colon and rectum. However, the costs and benefits of virtual colonoscopy are still being investigated, and the technique ...

Bevacizumab Injection

MedlinePlus

... in combination with another medication to treat renal cell cancer (RCC, a type of cancer that begins in ... of the colon or rectum, glioblastoma, or renal cell cancer and once every 3 weeks to treat lung ...

A novel geometry-dosimetry label fusion method in multi-atlas segmentation for radiotherapy: a proof-of-concept study

NASA Astrophysics Data System (ADS)

Chang, Jina; Tian, Zhen; Lu, Weiguo; Gu, Xuejun; Chen, Mingli; Jiang, Steve B.

2017-05-01

Multi-atlas segmentation (MAS) has been widely used to automate the delineation of organs at risk (OARs) for radiotherapy. Label fusion is a crucial step in MAS to cope with the segmentation variabilities among multiple atlases. However, most existing label fusion methods do not consider the potential dosimetric impact of the segmentation result. In this proof-of-concept study, we propose a novel geometry-dosimetry label fusion method for MAS-based OAR auto-contouring, which evaluates the segmentation performance in terms of both geometric accuracy and the dosimetric impact of the segmentation accuracy on the resulting treatment plan. Differently from the original selective and iterative method for performance level estimation (SIMPLE), we evaluated and rejected the atlases based on both Dice similarity coefficient and the predicted error of the dosimetric endpoints. The dosimetric error was predicted using our previously developed geometry-dosimetry model. We tested our method in MAS-based rectum auto-contouring on 20 prostate cancer patients. The accuracy in the rectum sub-volume close to the planning tumor volume (PTV), which was found to be a dosimetric sensitive region of the rectum, was greatly improved. The mean absolute distance between the obtained contour and the physician-drawn contour in the rectum sub-volume 2 mm away from PTV was reduced from 3.96 mm to 3.36 mm on average for the 20 patients, with the maximum decrease found to be from 9.22 mm to 3.75 mm. We also compared the dosimetric endpoints predicted for the obtained contours with those predicted for the physician-drawn contours. Our method led to smaller dosimetric endpoint errors than the SIMPLE method in 15 patients, comparable errors in 2 patients, and slightly larger errors in 3 patients. These results indicated the efficacy of our method in terms of considering both geometric accuracy and dosimetric impact during label fusion. Our algorithm can be applied to different tumor sites and radiation treatments, given a specifically trained geometry-dosimetry model.

Testicular Doses in Image-Guided Radiotherapy of Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deng Jun, E-mail: jun.deng@yale.edu; Chen Zhe; Yu, James B.

Purpose: To investigate testicular doses contributed by kilovoltage cone-beam computed tomography (kVCBCT) during image-guided radiotherapy (IGRT) of prostate cancer. Methods and Materials: An EGS4 Monte Carlo code was used to calculate three-dimensional dose distributions from kVCBCT on 3 prostate cancer patients. Absorbed doses to various organs were compared between intensity-modulated radiotherapy (IMRT) treatments and kVCBCT scans. The impact of CBCT scanning mode, kilovoltage peak energy (kVp), and CBCT field span on dose deposition to testes and other organs was investigated. Results: In comparison with one 10-MV IMRT treatment, a 125-kV half-fan CBCT scan delivered 3.4, 3.8, 4.1, and 5.7 cGymore » to the prostate, rectum, bladder, and femoral heads, respectively, accounting for 1.7%, 3.2%, 3.2%, and 8.4% of megavoltage photon dose contributions. However, the testes received 2.9 cGy from the same CBCT scan, a threefold increase as compared with 0.7 cGy received during IMRT. With the same kVp, full-fan mode deposited much less dose to organs than half-fan mode, ranging from 9% less for prostate to 69% less for testes, except for rectum, where full-fan mode delivered 34% more dose. As photon beam energy increased from 60 to 125 kV, kVCBCT-contributed doses increased exponentially for all organs, irrespective of scanning mode. Reducing CBCT field span from 30 to 10 cm in the superior-inferior direction cut testicular doses from 5.7 to 0.2 cGy in half-fan mode and from 1.5 to 0.1 cGy in full-fan mode. Conclusions: Compared with IMRT, kVCBCT-contributed doses to the prostate, rectum, bladder, and femoral heads are clinically insignificant, whereas dose to the testes is threefold more. Full-fan CBCT usually deposits much less dose to organs (except for rectum) than half-fan mode in prostate patients. Kilovoltage CBCT-contributed doses increase exponentially with photon beam energy. Reducing CBCT field significantly cuts doses to testes and other organs.« less

Intensity-modulated radiotherapy improves lymph node coverage and dose to critical structures compared with three-dimensional conformal radiation therapy in clinically localized prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang-Chesebro, Alice; Xia Ping; Coleman, Joy

2006-11-01

Purpose: The aim of this study was to quantify gains in lymph node coverage and critical structure dose reduction for whole-pelvis (WP) and extended-field (EF) radiotherapy in prostate cancer using intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3DCRT) for the first treatment phase of 45 Gy in the concurrent treatment of lymph nodes and prostate. Methods and Materials: From January to August 2005, 35 patients with localized prostate cancer were treated with pelvic IMRT; 7 had nodes defined up to L5-S1 (Group 1), and 28 had nodes defined above L5-S1 (Group 2). Each patient had 2 plans retrospectively generated:more » 1 WP 3DCRT plan using bony landmarks, and 1 EF 3DCRT plan to cover the vascular defined volumes. Dose-volume histograms for the lymph nodes, rectum, bladder, small bowel, and penile bulb were compared by group. Results: For Group 1, WP 3DCRT missed 25% of pelvic nodes with the prescribed dose 45 Gy and missed 18% with the 95% prescribed dose 42.75 Gy, whereas WP IMRT achieved V{sub 45Gy} = 98% and V{sub 42.75Gy} = 100%. Compared with WP 3DCRT, IMRT reduced bladder V{sub 45Gy} by 78%, rectum V{sub 45Gy} by 48%, and small bowel V{sub 45Gy} by 232 cm{sup 3}. EF 3DCRT achieved 95% coverage of nodes for all patients at high cost to critical structures. For Group 2, IMRT decreased bladder V{sub 45Gy} by 90%, rectum V{sub 45Gy} by 54% and small bowel V{sub 45Gy} by 455 cm{sup 3} compared with EF 3DCRT. Conclusion: In this study WP 3DCRT missed a significant percentage of pelvic nodes. Although EF 3DCRT achieved 95% pelvic nodal coverage, it increased critical structure doses. IMRT improved pelvic nodal coverage while decreasing dose to bladder, rectum, small bowel, and penile bulb. For patients with extended node involvement, IMRT especially decreases small bowel dose.« less

SU-E-T-202: Impact of Monte Carlo Dose Calculation Algorithm On Prostate SBRT Treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Venencia, C; Garrigo, E; Cardenas, J

2014-06-01

Purpose: The purpose of this work was to quantify the dosimetric impact of using Monte Carlo algorithm on pre calculated SBRT prostate treatment with pencil beam dose calculation algorithm. Methods: A 6MV photon beam produced by a Novalis TX (BrainLAB-Varian) linear accelerator equipped with HDMLC was used. Treatment plans were done using 9 fields with Iplanv4.5 (BrainLAB) and dynamic IMRT modality. Institutional SBRT protocol uses a total dose to the prostate of 40Gy in 5 fractions, every other day. Dose calculation is done by pencil beam (2mm dose resolution), heterogeneity correction and dose volume constraint (UCLA) for PTV D95%=40Gy andmore » D98%>39.2Gy, Rectum V20Gy<50%, V32Gy<20%, V36Gy<10% and V40Gy<5%, Bladder V20Gy<40% and V40Gy<10%, femoral heads V16Gy<5%, penile bulb V25Gy<3cc, urethra and overlap region between PTV and PRV Rectum Dmax<42Gy. 10 SBRT treatments plans were selected and recalculated using Monte Carlo with 2mm spatial resolution and mean variance of 2%. DVH comparisons between plans were done. Results: The average difference between PTV doses constraints were within 2%. However 3 plans have differences higher than 3% which does not meet the D98% criteria (>39.2Gy) and should have been renormalized. Dose volume constraint differences for rectum, bladder, femoral heads and penile bulb were les than 2% and within tolerances. Urethra region and overlapping between PTV and PRV Rectum shows increment of dose in all plans. The average difference for urethra region was 2.1% with a maximum of 7.8% and for the overlapping region 2.5% with a maximum of 8.7%. Conclusion: Monte Carlo dose calculation on dynamic IMRT treatments could affects on plan normalization. Dose increment in critical region of urethra and PTV overlapping region with PTV could have clinical consequences which need to be studied. The use of Monte Carlo dose calculation algorithm is limited because inverse planning dose optimization use only pencil beam.« less

SU-E-T-280: Reconstructed Rectal Wall Dose Map-Based Verification of Rectal Dose Sparing Effect According to Rectum Definition Methods and Dose Perturbation by Air Cavity in Endo-Rectal Balloon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, J; Research Institute of Biomedical Engineering, The Catholic University of Korea, Seoul; Park, H

Purpose: Dosimetric effect and discrepancy according to the rectum definition methods and dose perturbation by air cavity in an endo-rectal balloon (ERB) were verified using rectal-wall (Rwall) dose maps considering systematic errors in dose optimization and calculation accuracy in intensity-modulated radiation treatment (IMRT) for prostate cancer patients. Methods: When the inflated ERB having average diameter of 4.5 cm and air volume of 100 cc is used for patient, Rwall doses were predicted by pencil-beam convolution (PBC), anisotropic analytic algorithm (AAA), and AcurosXB (AXB) with material assignment function. The errors of dose optimization and calculation by separating air cavity from themore » whole rectum (Rwhole) were verified with measured rectal doses. The Rwall doses affected by the dose perturbation of air cavity were evaluated using a featured rectal phantom allowing insert of rolled-up gafchromic films and glass rod detectors placed along the rectum perimeter. Inner and outer Rwall doses were verified with reconstructed predicted rectal wall dose maps. Dose errors and extent at dose levels were evaluated with estimated rectal toxicity. Results: While AXB showed insignificant difference of target dose coverage, Rwall doses underestimated by up to 20% in dose optimization for the Rwhole than Rwall at all dose range except for the maximum dose. As dose optimization for Rwall was applied, the Rwall doses presented dose error less than 3% between dose calculation algorithm except for overestimation of maximum rectal dose up to 5% in PBC. Dose optimization for Rwhole caused dose difference of Rwall especially at intermediate doses. Conclusion: Dose optimization for Rwall could be suggested for more accurate prediction of rectal wall dose prediction and dose perturbation effect by air cavity in IMRT for prostate cancer. This research was supported by the Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (MSIP) (Grant No. 200900420)« less

SU-E-T-509: Inter-Observer and Inter-Modality Contouring Analysis for Organs at Risk for HDR Gynecological Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sadeghi, P; Smith, W; Tom Baker Cancer Centre, Calgary, AB

2015-06-15

Purpose This study quantifies errors associated with MR-guided High Dose Rate (HDR) gynecological brachytherapy. Uncertainties in this treatment results from contouring, organ motion between imaging and treatment delivery, dose calculation, and dose delivery. We focus on interobserver and inter-modality variability in contouring and the motion of organs at risk (OARs) in the time span between the MR and CT scans (∼1 hour). We report the change in organ volume and position of center of mass (CM) between the two imaging modalities. Methods A total of 8 patients treated with MR-guided HDR brachytherapy were included in this study. Two observers contouredmore » the bladder and rectum on both MR and CT scans. The change in OAR volume and CM position between the MR and CT imaging sessions on both image sets were calculated. Results The absolute mean bladder volume change between the two imaging modalities is 67.1cc. The absolute mean inter-observer difference in bladder volume is much lower at 15.5cc (MR) and 11.0cc (CT). This higher inter-modality volume difference suggests a real change in the bladder filling between the two imaging sessions. Change in Rectum volume inter-observer standard error of means (SEM) is 3.18cc (MR) and 3.09cc (CT), while the inter-modality SEM is 3.65cc (observer 1), and 2.75cc (observer 2). The SEM for rectum CM position in the superior-inferior direction was approximately three times higher than in other directions for both the inter—observer (0.77 cm, 0.92 cm for observers 1 and 2, respectively) and inter-modality (0.91 cm, 0.95 cm for MR and CT, respectively) variability. Conclusion Bladder contours display good consistency between different observers on both CT and MR images. For rectum contouring the highest inconsistency stems from the observers’ choice of the superior-inferior borders. A complete analysis of a larger patient cohort will enable us to separate the true organ motion from the inter-observer variability.« less

Dose Distribution in Bladder and Surrounding Normal Tissues in Relation to Bladder Volume in Conformal Radiotherapy for Bladder Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Majewski, Wojciech, E-mail: wmajewski1@poczta.onet.p; Wesolowska, Iwona; Urbanczyk, Hubert

2009-12-01

Purpose: To estimate bladder movements and changes in dose distribution in the bladder and surrounding tissues associated with changes in bladder filling and to estimate the internal treatment margins. Methods and Materials: A total of 16 patients with bladder cancer underwent planning computed tomography scans with 80- and 150-mL bladder volumes. The bladder displacements associated with the change in volume were measured. Each patient had treatment plans constructed for a 'partially empty' (80 mL) and a 'partially full' (150 mL) bladder. An additional plan was constructed for tumor irradiation alone. A subsequent 9 patients underwent sequential weekly computed tomography scanningmore » during radiotherapy to verify the bladder movements and estimate the internal margins. Results: Bladder movements were mainly observed cranially, and the estimated internal margins were nonuniform and largest (>2 cm) anteriorly and cranially. The dose distribution in the bladder worsened if the bladder increased in volume: 70% of patients (11 of 16) would have had bladder underdosed to <95% of the prescribed dose. The dose distribution in the rectum and intestines was better with a 'partially empty' bladder (volume that received >70%, 80%, and 90% of the prescribed dose was 23%, 20%, and 15% for the rectum and 162, 144, 123 cm{sup 3} for the intestines, respectively) than with a 'partially full' bladder (volume that received >70%, 80%, and 90% of the prescribed dose was 28%, 24%, and 18% for the rectum and 180, 158, 136 cm{sup 3} for the intestines, respectively). The change in bladder filling during RT was significant for the dose distribution in the intestines. Tumor irradiation alone was significantly better than whole bladder irradiation in terms of organ sparing. Conclusion: The displacements of the bladder due to volume changes were mainly related to the upper wall. The internal margins should be nonuniform, with the largest margins cranially and anteriorly. The changes in bladder filling during RT could influence the dose distribution in the bladder and intestines. The dose distribution in the rectum and bowel was slightly better with a 'partially empty' than with a 'full' bladder.« less

SU-F-J-27: Segmentation of Prostate CBCT Images with Implanted Calypso Transponders Using Double Haar Wavelet Transform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Y; Saleh, Z; Tang, X

Purpose: Segmentation of prostate CBCT images is an essential step towards real-time adaptive radiotherapy. It is challenging For Calypso patients, as more artifacts are generated by the beacon transponders. We herein propose a novel wavelet-based segmentation algorithm for rectum, bladder, and prostate of CBCT images with implanted Calypso transponders. Methods: Five hypofractionated prostate patients with daily CBCT were studied. Each patient had 3 Calypso transponder beacons implanted, and the patients were setup and treated with Calypso tracking system. Two sets of CBCT images from each patient were studied. The structures (i.e. rectum, bladder, and prostate) were contoured by a trainedmore » expert, and these served as ground truth. For a given CBCT, the moving window-based Double Haar transformation is applied first to obtain the wavelet coefficients. Based on a user defined point in the object of interest, a cluster algorithm based adaptive thresholding is applied to the low frequency components of the wavelet coefficients, and a Lee filter theory based adaptive thresholding is applied to the high frequency components. For the next step, the wavelet reconstruction is applied to the thresholded wavelet coefficients. A binary/segmented image of the object of interest is therefore obtained. DICE, sensitivity, inclusiveness and ΔV were used to evaluate the segmentation result. Results: Considering all patients, the bladder has the DICE, sensitivity, inclusiveness, and ΔV ranges of [0.81–0.95], [0.76–0.99], [0.83–0.94], [0.02–0.21]. For prostate, the ranges are [0.77–0.93], [0.84–0.97], [0.68–0.92], [0.1–0.46]. For rectum, the ranges are [0.72–0.93], [0.57–0.99], [0.73–0.98], [0.03–0.42]. Conclusion: The proposed algorithm appeared effective segmenting prostate CBCT images with the present of the Calypso artifacts. However, it is not robust in two scenarios: 1) rectum with significant amount of gas; 2) prostate with very low contrast. Model based algorithm might improve the segmentation in these two scenarios.« less

A novel two-step optimization method for tandem and ovoid high-dose-rate brachytherapy treatment for locally advanced cervical cancer.

PubMed

Sharma, Manju; Fields, Emma C; Todor, Dorin A

2015-01-01

To present a novel method allowing fast volumetric optimization of tandem and ovoid high-dose-rate treatments and to quantify its benefits. Twenty-seven CT-based treatment plans from 6 consecutive cervical cancer patients treated with four to five intracavitary tandem and ovoid insertions were used. Initial single-step optimized plans were manually optimized, approved, and delivered plans created with a goal to cover high-risk clinical target volume (HR-CTV) with D90 >90% and minimize rectum, bladder, and sigmoid D2cc. For the two-step optimized (TSO) plan, each single-step optimized plan was replanned adding a structure created from prescription isodose line to the existent physician delineated HR-CTV, rectum, bladder, and sigmoid. New, more rigorous dose-volume histogram constraints for the critical organs at risks (OARs) were used for the optimization. HR-CTV D90 and OAR D2ccs were evaluated in both plans. TSO plans had consistently smaller D2ccs for all three OARs while preserving HR-CTV D90. On plans with "excellent" CTV coverage, average D90 of 96% (91-102%), sigmoid, bladder, and rectum D2cc, respectively, reduced on average by 37% (16-73%), 28% (20-47%), and 27% (15-45%). Similar reductions were obtained on plans with "good" coverage, average D90 of 93% (90-99%). For plans with "inferior" coverage, average D90 of 81%, the coverage increased to 87% with concurrent D2cc reductions of 31%, 18%, and 11% for sigmoid, bladder, and rectum, respectively. The TSO can be added with minimal planning time increase but with the potential of dramatic and systematic reductions in OAR D2ccs and in some cases with concurrent increase in target dose coverage. These single-fraction modifications would be magnified over the course of four to five intracavitary insertions and may have real clinical implications in terms of decreasing both acute and late toxicities. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Comparison of doses to the rectum derived from treatment planning system with in-vivo dose values in vaginal vault brachytherapy using cylinder applicators

PubMed Central

Obed, Rachel Ibhade; Akinlade, Bidemi Idayat; Ntekim, Atara

2015-01-01

Purpose In-vivo measurements to determine doses to organs-at-risk can be an essential part of brachytherapy quality assurance (QA). This study compares calculated doses to the rectum with measured dose values as a means of QA in vaginal vault brachytherapy using cylinder applicators. Material and methods At the Department of Radiotherapy, University College Hospital (UCH), Ibadan, Nigeria, intracavitary brachytherapy (ICBT) was delivered by a GyneSource high-dose-rate (HDR) unit with 60Co. Standard 2D treatment plans were created with HDR basic 2.6 software for prescription doses 5-7 Gy at points 5 mm away from the posterior surface of vaginal cylinder applicators (20, 25, and 30 mm diameters). The LiF:Mg, Ti thermoluminescent dosimeter rods (1 x 6 mm) were irradiated to a dose of 7 Gy on Theratron 60Co machine for calibration purpose prior to clinical use. Measurements in each of 34 insertions involving fourteen patients were performed with 5 TLD-100 rods placed along a re-usable rectal marker positioned in the rectum. The dosimeters were read in Harshaw 3500 TLD reader and compared with doses derived from the treatment planning system (TPS) at 1 cm away from the dose prescription points. Results The mean calculated and measured doses ranged from 2.1-3.8 Gy and 1.2-5.6 Gy with averages of 3.0 ± 0.5 Gy and 3.1 ± 1.1 Gy, respectively, for treatment lengths 2-8 cm along the cylinder-applicators. The mean values correspond to 48.9% and 50.8% of the prescribed doses, respectively. The deviations of the mean in-vivo doses from the TPS values ranged from –1.9 to 2.1 Gy with a p-value of 0.427. Conclusions This study was part of efforts to verify rectal dose obtained from the TPS during vaginal vault brachytherapy. There was no significant difference in the dose to the rectum from the two methods of measurements. PMID:26816506

Spatiotemporal filtering of MR-temperature artifacts arising from bowel motion during transurethral MR-HIFU

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmitt, Alain, E-mail: aschmitt@sri.utoronto.ca; Mougenot, Charles; Chopra, Rajiv

2014-11-01

Purpose: Transurethral MR-HIFU is a minimally invasive image-guided treatment for localized prostate cancer that enables precise targeting of tissue within the gland. The treatment is performed within a clinical MRI to obtain real-time MR thermometry used as an active feedback to control the spatial heating pattern in the prostate and to monitor for potential damage to surrounding tissues. This requires that the MR thermometry measurements are an accurate representation of the true tissue temperature. The proton resonance frequency shift thermometry method used is sensitive to tissue motion and changes in the local magnetic susceptibility that can be caused by themore » motion of air bubbles in the rectum, which can impact the performance of transurethral MR-HIFU in these regions of the gland. Methods: A method is proposed for filtering of temperature artifacts based on the temporal variance of the temperature, using empirical and dynamic positional knowledge of the ultrasonic heating beam, and an estimation of the measurement noise. A two-step correction strategy is introduced which eliminates artifact-detected temperature variations while keeping the noise level low through spatial averaging. Results: The filter has been evaluated by postprocessing data from five human transurethral ultrasound treatments. The two-step correction process led to reduced final temperature standard deviation in the prostate and rectum areas where the artifact was located, without negatively affecting areas distal to the artifact. The performance of the filter was also found to be consistent across all six of the data sets evaluated. The evaluation of the detection criterion parameter M determined that a value of M = 3 achieves a conservative filter with minimal loss of spatial resolution during the process. Conclusions: The filter was able to remove most artifacts due to the presence of moving air bubbles in the rectum during transurethral MR-HIFU. A quantitative estimation of the filter capabilities shows a systematic improvement in the standard deviation of the corrected temperature maps in the rectum zone as well as in the entire acquired slice.« less

Electromagnetic organ tracking allows for real-time compensation of tissue shift in image-guided laparoscopic rectal surgery: results of a phantom study.

PubMed

Wagner, M; Gondan, M; Zöllner, C; Wünscher, J J; Nickel, F; Albala, L; Groch, A; Suwelack, S; Speidel, S; Maier-Hein, L; Müller-Stich, B P; Kenngott, H G

2016-02-01

Laparoscopic resection is a minimally invasive treatment option for rectal cancer but requires highly experienced surgeons. Computer-aided technologies could help to improve safety and efficiency by visualizing risk structures during the procedure. The prerequisite for such an image guidance system is reliable intraoperative information on iatrogenic tissue shift. This could be achieved by intraoperative imaging, which is rarely available. Thus, the aim of the present study was to develop and validate a method for real-time deformation compensation using preoperative imaging and intraoperative electromagnetic tracking (EMT) of the rectum. Three models were compared and evaluated for the compensation of tissue deformation. For model A, no compensation was performed. Model B moved the corresponding points rigidly to the motion of the EMT sensor. Model C used five nested linear regressions with increasing level of complexity to compute the deformation (C1-C5). For evaluation, 14 targets and an EMT organ sensor were fit into a silicone-molded rectum of the OpenHELP phantom. Following a computed tomography, the image guidance was initiated and the rectum was deformed in the same way as during surgery in a total of 14 experimental runs. The target registration error (TRE) was measured for all targets in different positions of the rectum. The mean TRE without correction (model A) was 32.8 ± 20.8 mm, with only 19.6% of the measurements below 10 mm (80.4% above 10 mm). With correction, the mean TRE could be reduced using the rigid correction (model B) to 6.8 ± 4.8 mm with 78.7% of the measurements being <10 mm. Using the most complex linear regression correction (model C5), the error could be reduced to 2.9 ± 1.4 mm with 99.8% being below 10 mm. In laparoscopic rectal surgery, the combination of electromagnetic organ tracking and preoperative imaging is a promising approach to compensating for intraoperative tissue shift in real-time.

SU-F-19A-03: Dosimetric Advantages in Critical Structure Dose Sparing by Using a Multichannel Cylinder in High Dose Rate Brachytherapy to Treat Vaginal Cuff Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Syh, J; Syh, J; Patel, B

2014-06-15

Purpose: The multichannel cylindrical vaginal applicator is a variation of traditional single channel cylindrical vaginal applicator. The multichannel applicator has additional peripheral channels that provide more flexibility in the planning process. The dosimetric advantage is to reduce dose to adjacent organ at risk (OAR) such as bladder and rectum while maintaining target coverage with the dose optimization from additional channels. Methods: Vaginal HDR brachytherapy plans are all CT based. CT images were acquired in 2 mm thickness to keep integrity of cylinder contouring. The CTV of 5mm Rind with prescribed treatment length was reconstructed from 5mm expansion of inserted cylinder.more » The goal was 95% of CTV covered by 95% of prescribed dose in both single channel planning (SCP)and multichannel planning (MCP) before proceeding any further optimization for dose reduction to critical structures with emphasis on D2cc and V2Gy . Results: This study demonstrated noticeable dose reduction to OAR was apparent in multichannel plans. The D2cc of the rectum and bladder were showing the reduced dose for multichannel versus single channel. The V2Gy of the rectum was 93.72% and 83.79% (p=0.007) for single channel and multichannel respectively (Figure 1 and Table 1). To assure adequate coverage to target while reducing the dose to the OAR without any compromise is the main goal in using multichannel vaginal applicator in HDR brachytherapy. Conclusion: Multichannel plans were optimized using anatomical based inverse optimization algorithm of inverse planning simulation annealing. The optimization solution of the algorithm was to improve the clinical target volume dose coverage while reducing the dose to critical organs such as bladder, rectum and bowels. The comparison between SCP and MCP demonstrated MCP is superior to SCP where the dwell positions were based on geometric array only. It concluded that MCP is preferable and is able to provide certain features superior to SCP.« less

Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer.

PubMed

Yang, Ruijie; Zhao, Nan; Liao, Anyan; Wang, Hao; Qu, Ang

2016-01-01

To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78Gy in 39 fractions were prescribed for PTV. For HDR and LDR plans, the dose prescription was D90 of 34Gy in 8.5Gy per fraction, and 145Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2Gy per fraction, EQD2) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The Dmean (EQD2) of rectum decreased 22.36Gy in HDR and 17.01Gy in LDR from 30.24Gy in VMAT, respectively. The Dmean (EQD2) of bladder decreased 6.91Gy in HDR and 2.53Gy in LDR from 13.46Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD2) was 80.26, 70.23, and 104.91Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

A novel geometry-dosimetry label fusion method in multi-atlas segmentation for radiotherapy: a proof-of-concept study.

PubMed

Chang, Jina; Tian, Zhen; Lu, Weiguo; Gu, Xuejun; Chen, Mingli; Jiang, Steve B

2017-05-07

Multi-atlas segmentation (MAS) has been widely used to automate the delineation of organs at risk (OARs) for radiotherapy. Label fusion is a crucial step in MAS to cope with the segmentation variabilities among multiple atlases. However, most existing label fusion methods do not consider the potential dosimetric impact of the segmentation result. In this proof-of-concept study, we propose a novel geometry-dosimetry label fusion method for MAS-based OAR auto-contouring, which evaluates the segmentation performance in terms of both geometric accuracy and the dosimetric impact of the segmentation accuracy on the resulting treatment plan. Differently from the original selective and iterative method for performance level estimation (SIMPLE), we evaluated and rejected the atlases based on both Dice similarity coefficient and the predicted error of the dosimetric endpoints. The dosimetric error was predicted using our previously developed geometry-dosimetry model. We tested our method in MAS-based rectum auto-contouring on 20 prostate cancer patients. The accuracy in the rectum sub-volume close to the planning tumor volume (PTV), which was found to be a dosimetric sensitive region of the rectum, was greatly improved. The mean absolute distance between the obtained contour and the physician-drawn contour in the rectum sub-volume 2 mm away from PTV was reduced from 3.96 mm to 3.36 mm on average for the 20 patients, with the maximum decrease found to be from 9.22 mm to 3.75 mm. We also compared the dosimetric endpoints predicted for the obtained contours with those predicted for the physician-drawn contours. Our method led to smaller dosimetric endpoint errors than the SIMPLE method in 15 patients, comparable errors in 2 patients, and slightly larger errors in 3 patients. These results indicated the efficacy of our method in terms of considering both geometric accuracy and dosimetric impact during label fusion. Our algorithm can be applied to different tumor sites and radiation treatments, given a specifically trained geometry-dosimetry model.

SU-E-J-228: MRI-Based Planning: Dosimetric Feasibility of Dose Painting for ADCDefined Intra-Prostatic Tumor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, X; Dalah, E; Prior, P

Purpose: Apparent diffusion coefficient (ADC) map may help to delineate the gross tumor volume (GTV) in prostate gland. Dose painting with external beam radiotherapy for GTV might increase the local tumor control. The purpose of this study is to explore the maximum boosting dose on GTV using VMAT without sacrificing sparing of organs at risk (OARs) in MRI based planning. Methods: VMAT plans for 5 prostate patients were generated following the commonly used dose volume (DV) criteria based on structures contoured on T2 weighted MRI with bulk electron density assignment using electron densities derived from ICRU46. GTV for each patientmore » was manually delineated based on ADC maps and fused to T2-weighted image set for planning study. A research planning system with Monte Carlo dose engine (Monaco, Elekta) was used to generate the VMAT plans with boosting dose on GTV gradually increased from 85Gy to 100Gy. DV parameters, including V(boosting-dose) (volume covered by boosting dose) for GTV, V75.6Gy for PTV, V45Gy, V70Gy, V72Gy and D1cc (Maximum dose to 1cc volume) for rectum and bladder, were used to measure plan quality. Results: All cases achieve at least 99.0% coverage of V(boosting-dose) on GTV and 95% coverage of V75.6Gy to the PTV. All the DV criteria, V45Gy≤50% and V70Gy≤15% for bladder and rectum, D1cc ≤77Gy (Rectum) and ≤80Gy (Bladder), V72Gy≤5% (rectum and bladder) were maintained when boosting GTV to 95Gy for all cases studied. Except for two patients, all the criteria were also met when the boosting dose goes to 100Gy. Conclusion: It is dosimetrically feasible safe to boost the dose to at least 95Gy to ADC defined GTV in prostate cancer using MRI guided VMAT delivery. Conclusion: It is dosimetrically feasible safe to boost the dose to at least 95Gy to ADC defined GTV in prostate cancer using MRI guided VMAT delivery. This research is partially supported by Elekta Inc.« less

Adjuvant radiation therapy for bladder cancer: A dosimetric comparison of techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baumann, Brian C.; Noa, Kate; Wileyto, E. Paul

Trials of adjuvant radiation after cystectomy are under development. There are no studies comparing radiation techniques to inform trial design. This study assesses the effect on bowel and rectal dose of 3 different modalities treating 2 proposed alternative clinical target volumes (CTVs). Contours of the bowel, rectum, CTV-pelvic sidewall (common/internal/external iliac and obturator nodes), and CTV-comprehensive (CTV-pelvic sidewall plus cystectomy bed and presacral regions) were drawn on simulation images of 7 post-cystectomy patients. We optimized 3-dimensional conformal radiation (3-D), intensity-modulated radiation (IMRT), and single-field uniform dose (SFUD) scanning proton plans for each CTV. Mixed models regression was used to comparemore » plans for bowel and rectal volumes exposed to 35% (V{sub 35%}), 65% (V{sub 65%}), and 95% (V{sub 95%}) of the prescribed dose. For any given treatment modality, treating the larger CTV-comprehensive volume compared with treating only the CTV-pelvic sidewall nodes significantly increased rectal dose (V{sub 35%} {sub rectum}, V{sub 65%} {sub rectum}, and V{sub 95%} {sub rectum}; p < 0.001 for all comparisons), but it did not produce significant differences in bowel dose (V{sub 95%} {sub bowel}, V{sub 65%} {sub bowel}, or V{sub 35%} {sub bowel}). The 3-D plans, compared with both the IMRT and the SFUD plans, had a significantly greater V{sub 65%} {sub bowel} and V{sub 95%} {sub bowel} for each proposed CTV (p < 0.001 for all comparisons). The effect of treatment modality on rectal dosimetry differed by CTV, but it generally favored the IMRT and the SFUD plans over the 3-D plans. Comparison of the IMRT plan vs the SFUD plan yielded mixed results with no consistent advantage for the SFUD plan over the IMRT plan. Targeting a CTV that spares the cystectomy bed and presacral region may marginally improve rectal toxicity but would not be expected to improve the bowel toxicity associated with any given modality of adjuvant radiation. Using the IMRT or the SFUD plans instead of the 3-D conformal plan may improve both bowel and rectal toxicity.« less

Dosimetric and radiobiological comparison of volumetric modulated arc therapy, high-dose rate brachytherapy, and low-dose rate permanent seeds implant for localized prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Ruijie, E-mail: ruijyang@yahoo.com; Zhao, Nan; Liao, Anyan

To investigate the dosimetric and radiobiological differences among volumetric modulated arc therapy (VMAT), high-dose rate (HDR) brachytherapy, and low-dose rate (LDR) permanent seeds implant for localized prostate cancer. A total of 10 patients with localized prostate cancer were selected for this study. VMAT, HDR brachytherapy, and LDR permanent seeds implant plans were created for each patient. For VMAT, planning target volume (PTV) was defined as the clinical target volume plus a margin of 5 mm. Rectum, bladder, urethra, and femoral heads were considered as organs at risk. A 78 Gy in 39 fractions were prescribed for PTV. For HDR andmore » LDR plans, the dose prescription was D{sub 90} of 34 Gy in 8.5 Gy per fraction, and 145 Gy to clinical target volume, respectively. The dose and dose volume parameters were evaluated for target, organs at risk, and normal tissue. Physical dose was converted to dose based on 2-Gy fractions (equivalent dose in 2 Gy per fraction, EQD{sub 2}) for comparison of 3 techniques. HDR and LDR significantly reduced the dose to rectum and bladder compared with VMAT. The D{sub mean} (EQD{sub 2}) of rectum decreased 22.36 Gy in HDR and 17.01 Gy in LDR from 30.24 Gy in VMAT, respectively. The D{sub mean} (EQD{sub 2}) of bladder decreased 6.91 Gy in HDR and 2.53 Gy in LDR from 13.46 Gy in VMAT. For the femoral heads and normal tissue, the mean doses were also significantly reduced in both HDR and LDR compared with VMAT. For the urethra, the mean dose (EQD{sub 2}) was 80.26, 70.23, and 104.91 Gy in VMAT, HDR, and LDR brachytherapy, respectively. For localized prostate cancer, both HDR and LDR brachytherapy were clearly superior in the sparing of rectum, bladder, femoral heads, and normal tissue compared with VMAT. HDR provided the advantage in sparing of urethra compared with VMAT and LDR.« less

Impact of dosimetric and clinical parameters on clinical side effects in cervix cancer patients treated with 3D pulse-dose-rate intracavitary brachytherapy.

PubMed

Levitchi, Mihai; Charra-Brunaud, Claire; Quetin, Philippe; Haie-Meder, Christine; Kerr, Christine; Castelain, Bernard; Delannes, Martine; Thomas, Laurence; Desandes, Emmanuel; Peiffert, Didier

2012-06-01

To assess the association between dosimetric/clinical parameters and gastrointestinal/urinary grade 2-4 side effects in cervix cancer patients treated with 3D pulse dose rate brachytherapy. Three hundred and fifty-two patients received brachytherapy associated with external-beam radiotherapy (EBRT) for 266 of them; 236 patients underwent surgery. The doses for the most exposed 2, and 0.1 cm(3) (D(2cc) and D(0.1cc)) volumes of the rectum and bladder as well as bladder ICRU point dose (D(ICRU)) were converted into isoeffective doses in 2-Gy fractions. The clinical parameters analyzed were: age, smoking habits, arteritis, diabetes, previous pelvic surgery, FIGO stage, nodal status, pathology, pelvic surgery, EBRT and chemotherapy. Side effects were prospectively assessed using the CTCAEv3.0. Cutoff dose levels were defined separately for patients treated with EBRT and brachytherapy (Group 1) and with preoperative brachytherapy (Group 2). The median follow-up was 23.4months. In Group 1 a significant predictive value of rectum D(0.1cc) and D(2cc), bladder D(0.1cc) and D(ICRU) for gastrointestinal and urinary toxicity was found using as cutoff 83, 68, 109 and 68Gy(α)(/)(β)(3). In Group 2 a significant predictive value of bladder D(0.1cc), D(2cc) and D(ICRU) for urinary toxicity was found using as cutoff 141, 91 and 67Gy(α)(/)(β)(3), but not for the rectum D(0.1cc) and D(2cc); smoking had a significant predictive value on urinary toxicity. For patients treated with brachytherapy and EBRT, rectum D(0.1cc) and D(2cc) and bladder D(0.1cc) and D(ICRU) had a predictive value for toxicity. For patients treated with preoperative brachytherapy, bladder D(0.1cc), D(2cc) and D(ICRU) and smoking had a predictive value for urinary toxicity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Dosimetric comparison of standard three-dimensional conformal radiotherapy followed by intensity-modulated radiotherapy boost schedule (sequential IMRT plan) with simultaneous integrated boost–IMRT (SIB IMRT) treatment plan in patients with localized carcinoma prostate

PubMed Central

Bansal, A.; Kapoor, R.; Singh, S. K.; Kumar, N.; Oinam, A. S.; Sharma, S. C.

2012-01-01

Aims: Dosimeteric and radiobiological comparison of two radiation schedules in localized carcinoma prostate: Standard Three-Dimensional Conformal Radiotherapy (3DCRT) followed by Intensity Modulated Radiotherapy (IMRT) boost (sequential-IMRT) with Simultaneous Integrated Boost IMRT (SIB-IMRT). Material and Methods: Thirty patients were enrolled. In all, the target consisted of PTV P + SV (Prostate and seminal vesicles) and PTV LN (lymph nodes) where PTV refers to planning target volume and the critical structures included: bladder, rectum and small bowel. All patients were treated with sequential-IMRT plan, but for dosimetric comparison, SIB-IMRT plan was also created. The prescription dose to PTV P + SV was 74 Gy in both strategies but with different dose per fraction, however, the dose to PTV LN was 50 Gy delivered in 25 fractions over 5 weeks for sequential-IMRT and 54 Gy delivered in 27 fractions over 5.5 weeks for SIB-IMRT. The treatment plans were compared in terms of dose–volume histograms. Also, Tumor Control Probability (TCP) and Normal Tissue Complication Probability (NTCP) obtained with the two plans were compared. Results: The volume of rectum receiving 70 Gy or more (V > 70 Gy) was reduced to 18.23% with SIB-IMRT from 22.81% with sequential-IMRT. SIB-IMRT reduced the mean doses to both bladder and rectum by 13% and 17%, respectively, as compared to sequential-IMRT. NTCP of 0.86 ± 0.75% and 0.01 ± 0.02% for the bladder, 5.87 ± 2.58% and 4.31 ± 2.61% for the rectum and 8.83 ± 7.08% and 8.25 ± 7.98% for the bowel was seen with sequential-IMRT and SIB-IMRT plans respectively. Conclusions: For equal PTV coverage, SIB-IMRT markedly reduced doses to critical structures, therefore should be considered as the strategy for dose escalation. SIB-IMRT achieves lesser NTCP than sequential-IMRT. PMID:23204659

[Laparoscopic surgery for malignancies of the colon, rectum, and anus in Lithuania in 2008].

PubMed

Samalavicius, Narimantas Evaldas; Rudinskaite, Giedre; Pavalkis, Dainius; Latkauskas, Tadas; Kaselis, Nerijus; Sidlauskas, Zilvinas; Sniuolis, Pranas; Poskus, Tomas; Kvedaras, Vytautas; Strupas, Kestutis; Poskus, Eligijus

2009-01-01

THE OBJECTIVE OF THIS STUDY: was to analyze data on laparoscopic surgery for malignant diseases of the colon, rectum, and anus in Lithuania during the period of January 1, 2005, to February 15, 2008. During the above-mentioned period in Lithuania, 130 laparoscopic surgeries for malignancies of colon, rectum, and anus were performed in seven different hospitals. There were 73 males and 57 females with a mean age of 68 years (range, 35-85 years). Laparoscopic procedures were attempted in 140 cases. Out of them, 130 were completed laparoscopically; 10 operations were converted to open, and conversion rate was 7.1%. Twenty-seven (20.8%) patients had stage I, 45 (34.6%) stage II, 45 (34.6%) stage III, and 13 (10%) stage IV disease. Ninety-two (70.8%) patients underwent straight laparoscopic surgery and 38 (29.2%) - hand-assisted laparoscopic surgery. Time in surgery was from 50 to 365 min, with a mean of 183 min. During 130 operations, in 11 (8.5%) cases, blood vessels were ligated through specimen retrieval site. Out of 104 operations, where anastomosis was performed (23 abdominoperineal resections and 3 Hartmann's procedures), in 68 (65.4%) cases it was done laparoscopically and in 36 (34.6%) cases using conventional extracorporal suturing. Hospital stay ranged from 7 to 59 days, with a mean of 12 days. One (0.8%) patient died. Postoperative complications occurred in 27 (20.8%) cases. Reoperation rate was 4.6% (6 cases). Complications were as follows: suture insufficiency (3 cases), eventration (3 cases), wound infection (7 cases), intraperitoneal abscess (1 case), abdominal wall phlegmon (1 case), intra-abdominal infiltrate (1 case), perineal hematoma (1 case), proctovaginal fistula (2 case), intraoperative bleeding from uterus (1 case), urinary retention (4 cases), cystitis (1 case), pneumonia (1 case), acute cardiovascular insufficiently (1 case). In histological specimens, 10 lymph nodes were found on the average (range, 2 to 27). Laparoscopic surgery for malignant diseases of the colon, rectum, and anus is dominating among laparoscopic surgeries for colorectum. Complication rate is similar to other authors. To evaluate disease relapse and outcomes, observation time is not sufficient yet.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonzalez-Sprinberg, G; Piriz, G

Purpose: To optimize the dose in bladder and rectum and show the different shapes of the isodose volumes in Co60-HDR brachytherapy, considering different utero and vaginal sources dwell ratio times (TU:TV). Methods: Besides Ir192-HDR, new Co60-HDR sources are being incorporated. We considered different TU:TV times and computed the dosis in bladder, rectum and at the reference points of the Manchester system. Also, we calculated the isodose volume and shape in each case. We used a EZAG-BEBIG Co0.A86 model with TPS HDRplus3.0.4. and LCT42-7, LCT42-2(R,L) applicators. A reference dose RA= 1.00 Gy was given to the A-right point. We considered themore » TU:TV dwell time ratios 1:0.25, 1:0.33, 1:0.5, 1:1, 1:2, 1:3, and 1:4. Given TU:TV, the stop time at each dwell position is fixed for each applicator. Results: Increasing TU:TV systematically results in a decreasing of the dose in bladder and rectum, e.g. 9% and 27% reduction were found in 1:0.25 with respect to 1:1, while 12% and 34% increase were found in 1:4 with respect to 1:1. Also, the isodose volume parameters height (h), width (w), thickness (t) and volume (hwt) increased from the 1:0.25 case to the 1:4 value: hwt is 25% lower and 31% higher than the 1:1 reference volume in these cases. Also w decreased for higher TU:TV and may compromise the tumoral volume coverage, decreasing 17% in the 1:0.25 case compared to the 1:1 case. The shape of the isodose volume was obtained for the different TU:TV considered. Conclusion: We obtained the shape of isodose volumes for different TU:TV values in gynecological Co60-HDR. We studied the dose reduction in bladder and rectum for different TU:TV ratios. The volume parameters and hwt are strongly dependent on this ratio. This information is useful for a quantitative check of the TPS and as a starting point towards optimization.« less

Barium enema (image)

MedlinePlus

A barium enema is performed to examine the walls of the colon. During the procedure, a well lubricated enema tube is inserted gently into the rectum. The barium, a radiopaque (shows up on X-ray) contrast ...

Proctitis

MedlinePlus

... of proctitis. They can be grouped as follows: Inflammatory bowel disease Autoimmune disease Harmful substances Non-sexually transmitted infection ... the rectum. Risk factors include: Autoimmune disorders , including inflammatory bowel disease High-risk sexual practices, such as anal sex ...

Prevalence of Bowel Incontinence

MedlinePlus

... Urinary Incontinence in Adults. December 12, 2007. Drossman DA, Li Z, Andruzzi E, et al. U.S. Householder ... Rectum Vol. 41, No. 10 October 1998. Drossman DA, Sandler RS, Broom CM, et al. Urgency and ...

Types of ileostomy

MedlinePlus

... an opening called a stoma in your belly. Waste will pass through the stoma into a pouch that collects ... ileostomy is thin or thick liquid. It is not solid like the stool that came from your rectum. ...

Osteogenesis Imperfecta Issues: Constipation

MedlinePlus

... to the diet. • Increase amount of fruits, fruit juice and vegetables. • Reduce amount of processed foods and ... This can put pressure on the rectum. Pressure, plus the lax or elastic muscles seen in the ...

Rectal culture (image)

MedlinePlus

A rectal culture test is performed by inserting a cotton swab in the rectum. The swab is rotated gently, and withdrawn. A smear of the swab is placed in culture media to encourage the growth of microorganisms. The ...

Hemorrhoids

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Rectocele

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Pilonidal Disease

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Hyperthermia for treating cancer

MedlinePlus

... forms of energy may be used, including: Radio waves Microwaves Ultrasound waves Heat may be delivered using: An external machine ... rectum. A needle-like probe to sends radio wave energy directly into the tumor to kill cancer ...

6 Common Cancers - Colorectal Cancer

MedlinePlus

... Bar Home Current Issue Past Issues 6 Common Cancers - Colorectal Cancer Past Issues / Spring 2007 Table of Contents For ... colon cancer. Photo: AP Photo/Ron Edmonds Colorectal Cancer Cancer of the colon (large intestine) or rectum ( ...

[Latex ligation in treatment of chronic hemorrhoids].

PubMed

Ektov, V N; Somov, K A

2015-01-01

We analyzed the results of treatment of 432 patients with chronic hemorrhoids using different variants of latex ligation. New technique including ligation of mucosa and submucosa of low-ampullar rectum providing ligation of hemorrhoidalvessels, lifting and recto-anal repair is developed and suggested. This method is advisable to use in case of chronic internal hemorrhoids stages I and II. The authors recommend simultaneous combined ligation of mucosa of low-ampullar rectum and internal hemorrhoids for stages III and IV. Different variants of latex ligation with external hemorrhoids excision were used in 103 patients. Pointed variants of latex ligation preserve important advantages including mini-invasiveness, simplicity and wide availability, low cost. Good remote results were obtained after these procedures in 87.3% of observations. Suggested tactics extends use of latex ligation and increases its effectiveness in treatment of different stages and forms of chronic hemorrhoids.

Laparoscopic restorative proctocolectomy ileal pouch anal anastomosis: How I do it?

PubMed

Madnani, Manish A; Mistry, Jitendra H; Soni, Harshad N; Shah, Atul J; Patel, Kantilal S; Haribhakti, Sanjiv P

2015-01-01

Surgery for ulcerative colitis is a major and complex colorectal surgery. Laparoscopy benefits these patients with better outcomes in context of cosmesis, pain and early recovery, especially in young patients. For surgeons, it is a better tool for improving vision and magnification in deep cavities. This is not the simple extension of the laparoscopy training. Starting from preoperative preparation to post operative care there are wide variations as compared to open surgery. There are also many variations in steps of laparoscopic surgery. It involves left colon, right colon and rectal mobilisation, low division of rectum, pouch creation and anastomosis of pouch to rectum. Over many years after standardisation of this technique, it takes same operative time as open surgery at our centre. So we present our standardized technique of laparoscopic assisted restorative proctocolectomy and ileal pouch anal anastomosis (IPAA).

Dosimetry for a uterine cervix cancer treatment

NASA Astrophysics Data System (ADS)

Rodríguez-Ponce, Miguel; Rodríguez-Villafuerte, Mercedes; Sánchez-Castro, Ricardo

2003-09-01

The dose distribution around the 3M 137Cs brachytherapy source as well as the same source inside the Amersham ASN 8231 applicator was measured using thermoluminescent dosimeters and radiochromic films. Some of the results were compared with those obtained from a Monte Carlo simulation and a good agreement was observed. The teletherapy dose distribution was measured using a pin-point ionization chamber. In addition, the experimental measurements and the Monte Carlo results were used to estimate the dose received in the rectum and bladder of an hypothetical patient treated with brachytherapy and compared with the dose distribution obtained from the Hospital's brachytherapy planning system. A 20 % dose reduction to the rectum and bladder was observed in both Monte Carlo and experimental measurements, compared with the results of the planning system, which results in a better dose control to these structures.

[A Case of Lymph Node Metastasis of Rectal Laterally Spreading Tumor with Mucosal Cancer after Endoscopic Submucosal Dissection].

PubMed

Ushigome, Hajime; Fujimoto, Yoshiya; Suzuki, Shinsuke; Minami, Hironori; Miyanari, Shun; Murahashi, Satoshi; Fukuoka, Hironori; Nagasaki, Toshiya; Akiyoshi, Takashi; Konishi, Tsuyoshi; Nagayama, Satoshi; Fukunaga, Yosuke; Ueno, Masashi; Chino, Akiko; Igarashi, Masahiro

2017-11-01

A screening fecal occult blood test was positive in a 76-year-old female. Colonoscopy showed laterally spreading tumor (LST)over 15 cm at lower rectum. endoscopic submucosal dissection(ESD)was performed. Pathological findings showed LST-G, 150×100 mm, adenocarcinoma(tub1-tub2), tubular adenoma, moderate-severe atypia, Tis(M), ly(-), v(-), HMX, VMX. Two years later CT detected one swollen lymph node at mesorectum and PET-CT showed FDG up take at the lymph node. We diagnosed lymph node metastasis, performed laparoscopic very low anterior resection. Pathological findings showed one lymph node metastasis, but there were no residual cancer at rectum. We cut the surgical specimen at 5mm intervals because of it's big size. It might be impossible with this procedure to detect SM invasion at this specimen.

Balantidium grimi n. sp. (Ciliophora, Litostomatea), a new species inhabiting the rectum of the frog Quasipaa spinosa from Lishui, China.

PubMed

Zhao, Weishan; Li, Can; Zhang, Dong; Wang, Runqiu; Zheng, Yingzhen; Zou, Hong; Li, Wenxiang; Wu, Shangong; Wang, Guitang; Li, Ming

2018-01-01

Balantidium grimi n. sp. is described from the rectum of the frog Quasipaa spinosa (Amphibia, Dicroglossidae) from Lishui, Zhejiang Province, China. The new species is described by both light microscopy (LM) and scanning electron microscopy (SEM), and a molecular phylogenetic analysis is also presented. This species has unique morphological features in that the body shape is somewhat flattened and the vestibulum is "V"-shaped, occupying nearly 3/8 to 4/7 of the body length. Only one contractile vacuole, situated at the posterior body, was observed. The phylogenetic analysis based on SSU-rDNA indicates that B. grimi groups together with B. duodeni and B. entozoon. In addition, the genus Balantidium is clearly polyphyletic. © W. Zhao et al., published by EDP Sciences, 2018.

Adherence to Survivorship Care Guidelines in Health Care Providers for Non-Small Cell Lung Cancer and Colorectal Cancer Survivor Care

ClinicalTrials.gov

2017-04-05

Adenocarcinoma of the Lung; Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Squamous Cell Lung Cancer; Stage I Colon Cancer; Stage I Rectal Cancer; Stage IA Non-small Cell Lung Cancer; Stage IB Non-small Cell Lung Cancer; Stage IIA Colon Cancer; Stage IIA Non-small Cell Lung Cancer; Stage IIA Rectal Cancer; Stage IIB Colon Cancer; Stage IIB Non-small Cell Lung Cancer; Stage IIB Rectal Cancer; Stage IIC Colon Cancer; Stage IIC Rectal Cancer; Stage IIIA Colon Cancer; Stage IIIA Non-small Cell Lung Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Non-small Cell Lung Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer

[Continence of anorectal sphincter complex in the early postoperative period after direct colo-anal anastomoses with colo-colic J pouch].

PubMed

Damianov, N; Tankova, L; Draganov, V

2003-01-01

According to up-to-date concepts for local spread of a rectal cancer it is possible to perform a radical rectal resection with a restorative anastomosis inspite of the fact that the tumor is located in the middle or the distal third of the rectum. Usually a total resection of the rectum and coloanal anstomosis have to be performed. There are two ways to restore the continuity of the gut: a straight coloanal anstomosis or J pouch anastomosis. 22 patients with rectal cancer localized between 4 and 9 cm from the anal verge, were operated and restorative anastomoses were performed. The first 18 patients were with a straight coloanal anastomosis. In the last 4 cases coloanal anastomoses were done between the anus and colocolic 7 cm J pouch. During the first month there were 6 patients with total and 9 with partial incontinence in the group with straight coloanal anastomosis. Transrectal sonography confirmed contractility of the puborectal muscle and sphinctermanometry showed lower resting tone and squeeze pressure in cases with incotinence. No incontinence was observed in the group with J pouch and the shinctermanometry data were the same as these of healthy controls. The rectal ampula has reservoir function and its loss after total resection of the rectum is the reason for frequent bowel movements, urgency and leakage. Reconstruction with a colonic J pouch is associated with better bowel function compared to the straight coloanal anastomosis.

A text-based data mining and toxicity prediction modeling system for a clinical decision support in radiation oncology: A preliminary study

NASA Astrophysics Data System (ADS)

Kim, Kwang Hyeon; Lee, Suk; Shim, Jang Bo; Chang, Kyung Hwan; Yang, Dae Sik; Yoon, Won Sup; Park, Young Je; Kim, Chul Yong; Cao, Yuan Jie

2017-08-01

The aim of this study is an integrated research for text-based data mining and toxicity prediction modeling system for clinical decision support system based on big data in radiation oncology as a preliminary research. The structured and unstructured data were prepared by treatment plans and the unstructured data were extracted by dose-volume data image pattern recognition of prostate cancer for research articles crawling through the internet. We modeled an artificial neural network to build a predictor model system for toxicity prediction of organs at risk. We used a text-based data mining approach to build the artificial neural network model for bladder and rectum complication predictions. The pattern recognition method was used to mine the unstructured toxicity data for dose-volume at the detection accuracy of 97.9%. The confusion matrix and training model of the neural network were achieved with 50 modeled plans (n = 50) for validation. The toxicity level was analyzed and the risk factors for 25% bladder, 50% bladder, 20% rectum, and 50% rectum were calculated by the artificial neural network algorithm. As a result, 32 plans could cause complication but 18 plans were designed as non-complication among 50 modeled plans. We integrated data mining and a toxicity modeling method for toxicity prediction using prostate cancer cases. It is shown that a preprocessing analysis using text-based data mining and prediction modeling can be expanded to personalized patient treatment decision support based on big data.

Iterative-cuts: longitudinal and scale-invariant segmentation via user-defined templates for rectosigmoid colon in gynecological brachytherapy.

PubMed

Lüddemann, Tobias; Egger, Jan

2016-04-01

Among all types of cancer, gynecological malignancies belong to the fourth most frequent type of cancer among women. In addition to chemotherapy and external beam radiation, brachytherapy is the standard procedure for the treatment of these malignancies. In the progress of treatment planning, localization of the tumor as the target volume and adjacent organs of risks by segmentation is crucial to accomplish an optimal radiation distribution to the tumor while simultaneously preserving healthy tissue. Segmentation is performed manually and represents a time-consuming task in clinical daily routine. This study focuses on the segmentation of the rectum/sigmoid colon as an organ-at-risk in gynecological brachytherapy. The proposed segmentation method uses an interactive, graph-based segmentation scheme with a user-defined template. The scheme creates a directed two-dimensional graph, followed by the minimal cost closed set computation on the graph, resulting in an outlining of the rectum. The graph's outline is dynamically adapted to the last calculated cut. Evaluation was performed by comparing manual segmentations of the rectum/sigmoid colon to results achieved with the proposed method. The comparison of the algorithmic to manual result yielded a dice similarity coefficient value of [Formula: see text], in comparison to [Formula: see text] for the comparison of two manual segmentations by the same physician. Utilizing the proposed methodology resulted in a median time of [Formula: see text], compared to 300 s needed for pure manual segmentation.

A phantom study on bladder and rectum dose measurements in brachytherapy of cervix cancer using FBX aqueous chemical dosimeter.

PubMed

Bansal, Anil K; Semwal, Manoj K; Arora, Deepak; Sharma, D N; Julka, P K; Rath, G K

2013-06-01

The ferrous sulphate-benzoic acid-xylenol orange (FBX) chemical dosimeter, due to its aqueous form can measure average volume doses and hence may overcome the limitations of point dosimetry. The present study was undertaken to validate the use of FBX dosimeter for rectum and bladder dose measurement during intracavitary brachytherapy (ICBT) and transperineal interstitial brachytherapy (TIB). We filled cylindrical polypropylene tubes (PT) and Foley balloons (FB) with FBX solution and used them as substitutes for rectum and bladder dose measurements respectively. A water phantom was fabricated with provision to place the Fletcher-type ICBT and MUPIT template applicators, and FBX filled PT and FB within the phantom. The phantom was then CT scanned for treatment planning and subsequent irradiation. Our results show that the average difference between DVH derived dose value and FBX measured dose is 3.5% (PT) and 13.7% (FB) for ICBT, and 9% (PT) and 9.9% (FB) for TIB. We believe that the FBX system should be able to provide accuracy and precision sufficient for routine quality assurance purposes. The advantage of the FBX system is its water equivalent composition, average volume dose measuring capability, and energy and temperature independent response as compared to TLD or semiconductor dosimeters. However, detailed studies will be needed with regards to its safety before actual in-vivo dose measurements are possible with the FBX dosimeter. Copyright © 2012 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

The new laparoscopic proctocolectomy training (in soft cadaver).

PubMed

Pattana-arun, Jirawat; Udomsawaengsup, Suthep; Sahakitrungruang, Chucheep; Tansatit, Tanvaa; Tantiphlachiva, Kasaya; Rojanasakul, Arun

2005-09-01

The purpose of the present study was to evaluate the quality of preservation (tissue plane, named vessels identification, consistency of colon and rectum), quality of performing procedures, difficulties and problems and finally the satisfaction of surgeons in laparoscopic proctocolectomy in soft cadaver. Colorectal Division, Department of Surgery and Surgical Training Center Department of Anatomy, Faculty of Medicine, Chulalongkorn University. Prospective descriptive study 10 soft cadavers were scheduled for laparoscopic proctocolectomy. The procedures (colon-rectum mobilization and named vessels identification) were performed by 14 experienced surgeons (8 colorectal surgeons) and assisted by surgical residents. The quality of preservation, successfulness and the satisfaction in performing the procedures were recorded using questionnaires for evaluation. The preservation was very good in every aspect especially tissue plane between colon, mesocolon and retroperitoneum which was clearly dissected, same asfasciapropria of rectum. The named vessels and the tissue consistency were very well preserved and tolerated to laparoscopic equipment handling. The surgeons were satisfied with the tissue handling and dissections. There were two difficulties, the first was air leakage but simply corrected with purse string suture and the second was unflavored smell which was not concerned. Laparoscopic proctocolectomy could be completely performed in soft cadaver. Laparoscopic proctocolectomy could be performed in soft cadavers with great satisfaction. Repeated practice is possible, so the surgeons can gain their experiences outside the operating theatre. This success may shorten the learning curve and may be the new era in cadaver-based training.

Fluid tagging for CT colonography: effectiveness of a 2-hour iodinated oral preparation after incomplete optical colonoscopy.

PubMed

Chang, Kevin J; Rekhi, Satinder S; Anderson, Stephan W; Soto, Jorge A

2011-01-01

To evaluate the distal extent and attenuation of bowel opacification achieved after administration of a single low volume dose of oral contrast 2 hours before computed tomographic colonography (CTC) after incomplete optical colonoscopy. This retrospective study included 144 patients undergoing CTC after incomplete colonoscopy from April 2006 to July 2008 at 2 separate medical centers. Each patient received 20 to 30 mL of diatrizoate meglumine and diatrizoate sodium solution 2 hours before being scanned. The distalmost extent of opacification was: stomach/small bowel, n = 13; cecum, n = 2; ascending colon, n = 7; transverse colon, n = 19; descending colon, n = 14; sigmoid colon, n = 24; rectum, n = 65. The mean attenuation of each opacified segment was: cecum, 449 Hounsfield units (HU); ascending colon, 474 HU; transverse colon, 468 HU; descending colon, 421 HU; sigmoid colon, 391 HU; and rectum, 382 HU. In 103 (71.5%) patients, oral contrast reached the distal colon (descending colon, sigmoid colon, or rectum). The oral contrast did not reach the colon in only 13 (9.0%) patients. Oral administration of a small volume hyperosmolar oral contrast agent 2 hours before CTC results in satisfactory colonic opacification in the majority of patients. Adding same-day fluid tagging in incomplete colonoscopy patients presenting for completion CTC should result in adequate fluid opacification for most of the colon, especially proximal segments not visualized at the time of incomplete colonoscopy.

Does perineural invasion of the myenteric plexus have a key role in annular rectal invasion and digestive system symptoms of prostate carcinoma patients?

PubMed

Hashimoto, Hirotsugu; Kurata, Atsushi; Nashiro, Tamaki; Kuroda, Masahiko; Horiuchi, Hajime

2015-12-01

Prostate carcinoma is one of the most common cancers globally. It relatively rarely invades the rectum, accounting for only about 4% of resected cases. About half of these cases of rectal invasion show an annular rectal stricture pattern. It has been hypothesized that anatomical structures, namely Denonvilliers fascia, may play an important role in annular rectal involvement of prostate carcinoma. Here, we propose another hypothesis: the reason for annular rectal invasion by prostate carcinoma is its extension along the myenteric plexus (Auerbach's plexus). We illustrate this using a case presentation and description of the symptoms of such cases. From a review of the literature, autonomic digestive system symptoms of rectal invasion of prostatic carcinoma, such as diarrhea, tenesmus, or fecal incontinence is seen in about half of cases, coinciding with the frequency of annular rectal invasion. Thus, by modifying the long-established hypothesis, our suggestion that prostate carcinoma spreads along the myenteric plexus when cancer cells invade beyond the Denonvilliers fascia to the rectum could explain the cause and frequency not only of the annular rectal invasion but also the digestive system symptoms related to this disease. The prognosis of prostate carcinoma invading the rectum is very poor; however, this new hypothesis might shed light on the digestive system symptoms associated with prostate carcinoma and might lead to recognition and treatment of these cases at a relatively early stage of rectal invasion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Equivalence of Gyn GEC-ESTRO guidelines for image guided cervical brachytherapy with EUD-based dose prescription

PubMed Central

2013-01-01

Background To establish a generalized equivalent uniform dose (gEUD) -based prescription method for Image Guided Brachytherapy (IGBT) that reproduces the Gyn GEC-ESTRO WG (GGE) prescription for cervix carcinoma patients on CT images with limited soft tissue resolution. Methods The equivalence of two IGBT planning approaches was investigated in 20 patients who received external beam radiotherapy (EBT) and 5 concomitant high dose rate IGBT treatments. The GGE planning strategy based on dose to the most exposed 2 cm3 (D2cc) was used to derive criteria for the gEUD-based planning of the bladder and rectum. The safety of gEUD constraints in terms of GGE criteria was tested by maximizing dose to the gEUD constraints for individual fractions. Results The gEUD constraints of 3.55 Gy for the rectum and 5.19 Gy for the bladder were derived. Rectum and bladder gEUD-maximized plans resulted in D2cc averages very similar to the initial GGE criteria. Average D2ccs and EUDs from the full treatment course were comparable for the two techniques within both sets of normal tissue constraints. The same was found for the tumor doses. Conclusions The derived gEUD criteria for normal organs result in GGE-equivalent IGBT treatment plans. The gEUD-based planning considers the entire dose distribution of organs in contrast to a single dose-volume-histogram point. PMID:24225184

Causes Of Lower Gastrointestinal Bleeding On Colonoscopy.

PubMed

Jehangiri, Attique-Ur-Rehman; Gul, Rahid; Hadayat, Rania; Khan, Adil Naseer; Zabiullah; Khursheed, Liaqat

2017-01-01

Bleeding from anus is usually referred as rectal bleeding but actually rectal bleeding is defined as bleeding from lower colon or rectum, which means bleeding from a place distal to ligament of Treitz. This study was conducted to determine the frequency of different causes of rectal bleeding in patients at Ayub Teaching Hospital, Abbottabad. One hundred and seventy-five patients with evidence of rectal bleed, without gender discrimination were selected by non-probability convenient sampling from the out-patient department and general medical wards. Patients with suspected upper GI source of bleeding; acute infectious bloody diarrhoea and any coagulopathy were excluded from the study. All patients were subjected to fibre optic colonoscopy after preparation of the gut and findings were recorded. Where necessary, biopsy samples were also taken. Diagnosis was based on colonoscopic findings. A total of 175 patients (92 males and 83 females) with mean age 35.81±9.18 years were part of the study. Colonoscopy showed abnormal findings in 150 (85.7%) patients. The commonest diagnosis was haemorrhoids, which was found in 39 (22.3%) patients. It was followed by inflammatory bowel disease (IBD) in 30 (17.1%) patients, solitary rectal ulcer in 13 (7.4%) patients and polyps in 25 (14.3%) patients. Other less frequent findings were non-specific inflammation and fungating growths in rectum. Haemorrhoids was the leading cause of bleeding per rectum in this study, followed by evidence of IBD while infrequent findings of polyps and diverticuli indicate that these are uncommon in this region.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr; Udrescu, Corina; Department of Medical Physics, Centre Hospitalier Lyon Sud, Pierre Benite

Purpose: The aim of this study was to evaluate the contribution of an injection of hyaluronic acid (HA) between the rectum and the prostate for reducing the dose to the rectal wall in a hypofractionated irradiation for prostate cancer. Methods and Materials: In a phase 2 study, 10 cc of HA was injected between the rectum and prostate. For 16 patients, the same intensity modulated radiation therapy plan (62 Gy in 20 fractions) was optimized on 2 computed tomography scans: CT1 (before injection) and CT2 (after injection). Rectal parameters were compared: dose to 2.5 cc (D2.5), 5 cc (D5), 10more » cc (D10), 15 cc (D15), and 20 cc (D20) of rectal wall and volume of rectum covered by the 90% isodose line (V90), 80% (V80), 70% (V70), 60% (V60), and 50% (V50). Results: The mean V90, V80, V70, V60, and V50 values were reduced by 73.8% (P<.0001), 55.7% (P=.0003), 43.0% (P=.007), 34% (P=.002), and 25% (P=.036), respectively. The average values of D2.5, D5, D10, D15, and D20 were reduced by 8.5 Gy (P<.0001), 12.3 Gy (P<.0001), 8.4 Gy (P=.005), 3.7 Gy (P=.026), and 1.2 Gy (P=.25), respectively. Conclusions: The injection of HA significantly limited radiation doses to the rectal wall.« less

Foreign Objects in the Rectum

MedlinePlus

... Resources In This Article Medical Dictionary Also of Interest (Quiz) Anal Fissure (News) Could a Common Blood Thinner Lower Cancer Risk? (News) Study Untangles Disparity in Colon Cancer Survival Rates (News) Poor Prognosis for Diabetic Foot Sores (News) ...

How Are Pelvic Floor Disorders Diagnosed?

MedlinePlus

... Share Facebook Twitter Pinterest Email Print How are pelvic floor disorders diagnosed? A physical exam may be all ... fee ). This test is used to evaluate the pelvic floor and rectum while the patient is having a ...

Phase II Trial of FOLFOX6, Bevacizumab and Cetuximab in Patients With Colorectal Cancer

ClinicalTrials.gov

2015-06-26

Adenocarcinoma of the Rectum; Mucinous Adenocarcinoma of the Colon; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Stage IV Colon Cancer; Stage IV Rectal Cancer

Cetuximab Injection

MedlinePlus

... other medications to treat a certain type of cancer of the head and neck. Cetuximab is also used alone or in combination with other medications to treat a certain type of cancer of the colon (large intestine) or rectum that ...

Anal Abscess/Fistula

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Effect of various methods for rectum delineation on relative and absolute dose-volume histograms for prostate IMRT treatment planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kusumoto, Chiaki; Ohira, Shingo; Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita

2016-07-01

Several reports have dealt with correlations of late rectal toxicity with rectal dose-volume histograms (DVHs) for high dose levels. There are 2 techniques to assess rectal volume for reception of a specific dose: relative-DVH (R-DVH, %) that indicates relative volume for a vertical axis, and absolute-DVH (A-DVH, cc) with its vertical axis showing absolute volume of the rectum. The parameters of DVH vary depending on the rectum delineation method, but the literature does not present any standardization of such methods. The aim of the present study was to evaluate the effects of different delineation methods on rectal DVHs. The enrollmentmore » for this study comprised 28 patients with high-risk localized prostate cancer, who had undergone intensity-modulated radiation therapy (IMRT) with the prescription dose of 78 Gy. The rectum was contoured with 4 different methods using 2 lengths, short (Sh) and long (Lg), and 2 cross sections, rectum (Rec) and rectal wall (Rw). Sh means the length from 1 cm above the seminal vesicles to 1 cm below the prostate and Lg the length from the rectosigmoid junction to the anus. Rec represents the entire rectal volume including the rectal contents and Rw the rectal volume of the area with a wall thickness of 4 mm. We compared dose-volume parameters by using 4 rectal contour methods for the same plan with the R-DVHs as well as the A-DVHs. For the high dose levels, the R-DVH parameters varied widely. The mean of V{sub 70} for Sh-Rw was the highest (19.4%) and nearly twice as high as that for Lg-Rec (10.4%). On the contrary, only small variations were observed in the A-DVH parameters (4.3, 4.3, 5.5, and 5.5 cc for Sh-Rw, Lg-Rw, Sh-Rec, and Lg-Rec, respectively). As for R-DVHs, the parameters of V{sub 70} varied depending on the rectal lengths (Sh-Rec vs Lg-Rec: R = 0.76; Sh-Rw vs Lg-Rw: R = 0.85) and cross sections (Sh-Rec vs Sh-Rw: R = 0.49; Lg-Rec vs Lg-Rw: R = 0.65). For A-DVHs, however, the parameters of Sh rectal A-DVHs hardly changed regardless of differences in rectal length at all dose levels. Moreover, at high dose levels (V{sub 70}), the parameters of A-DVHs showed less dependence on rectal cross sections (Sh-Rec vs Sh-Rw: R = 0.66; Lg-Rec vs Lg-Rw: R = 0.59). This study showed that A-DVHs were less dependent on the delineation methods than R-DVHs, especially for evaluating the rectal dose at higher dose levels. It can therefore be assumed that, in addition to R-DVHs, A-DVHs can be used for evaluating rectal toxicity.« less

Colorectal Cancer Screening: A Circle of Health for Alaskans

MedlinePlus

... in the colon and rectum is often called colorectal cancer. But in this brochure we use the term ... tests can be used to find polyps or colorectal cancer. Each can be used alone. Sometimes they are ...

Large bowel resection

MedlinePlus

... blockage in the intestine due to scar tissue Colon cancer Diverticular disease (disease of the large bowel) Other reasons for bowel resection are: Familial polyposis (polyps are growths on the lining of the colon or rectum) Injuries that damage the large bowel ...

Colorectal Cancer—Patient Version

Cancer.gov

Colorectal cancer often begins as a growth called a polyp inside the colon or rectum. Finding and removing polyps can prevent colorectal cancer. Start here to find information on colon and rectal cancer treatment, causes and prevention, screening, research, and statistics.

Laparoscopic Surgery - What Is It?

MedlinePlus

... ensuring high-quality patient care by advancing the science, prevention and management of disorders and diseases of the colon, rectum and anus. These brochures are inclusive but not prescriptive. Their purpose is to provide information on diseases and processes, ...

Vaginal Fistula

MedlinePlus

Vaginal fistula Overview A vaginal fistula is an abnormal opening that connects your vagina to another organ, such as your bladder, colon or rectum. Your ... describe the condition as a hole in your vagina that allows stool or urine to pass through ...

Metastatic Neuroendocrine Tumour in a Renal Transplant Recipient: Dual-Tracer PET-CT with (18)F-FDG and (68)Ga-DOTANOC in This Rare Setting.

PubMed

Karunanithi, Sellam; Roy, Shambo Guha; Sharma, Punit; Yadav, Rajni; Bal, Chandrasekhar; Kumar, Rakesh

2015-03-01

Recipients of renal transplant are at increased risk of developing various malignancies, especially post-transplant lymphoproliferative disorder (PTLD) and skin cancers. Neuroendocrine tumours (NET) of the gastrointestinal tract have not been reported in this setting. Here we describe the case of a 75-year-old male who had undergone renal transplant 8 years back and now presented with significant weight loss and backache, clinically suspected as PTLD. (18)F-Fluordeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) showed hypermetabolic lesions in the liver and rectum, raising the suspicion of PTLD. However, biopsy from the liver lesion showed poorly differentiated NET. (68)Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-NaI(3)-octreotide ((68)Ga-DOTANOC) PET-CT was then done, which confirmed the primary lesion in the rectum with liver metastases.

Probiotics to prevent urinary tract infections: the rationale and evidence.

PubMed

Reid, Gregor; Bruce, Andrew W

2006-02-01

For over 30 years, urologists have recognized in females, that urinary pathogens almost always infect the host through ascension from the rectum, vagina to the urethra and bladder. Likewise, the Lactobacillus organisms that predominate in the vagina of healthy women, spread from the rectum and perineum and form a barrier in the vagina to bladder entry by uropathogens. The concept of artificially boosting the lactobacilli numbers through probiotic instillation has long been conceived, but only in recent years shown to be possible. Not all lactobacilli are effective, and to date clinical efficacy only exists for Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri B-54 and RC-14. These strains are only commercially available in Austria, and therefore for most urologists, while some probiotic organisms may reduce the recurrences of bladder cancer or oxaluria, no probiotics can be recommended widely to prevent UTI at present.

Laparoscopic restorative proctocolectomy ileal pouch anal anastomosis: How I do it?

PubMed Central

Madnani, Manish A; Mistry, Jitendra H; Soni, Harshad N; Shah, Atul J; Patel, Kantilal S; Haribhakti, Sanjiv P

2015-01-01

Surgery for ulcerative colitis is a major and complex colorectal surgery. Laparoscopy benefits these patients with better outcomes in context of cosmesis, pain and early recovery, especially in young patients. For surgeons, it is a better tool for improving vision and magnification in deep cavities. This is not the simple extension of the laparoscopy training. Starting from preoperative preparation to post operative care there are wide variations as compared to open surgery. There are also many variations in steps of laparoscopic surgery. It involves left colon, right colon and rectal mobilisation, low division of rectum, pouch creation and anastomosis of pouch to rectum. Over many years after standardisation of this technique, it takes same operative time as open surgery at our centre. So we present our standardized technique of laparoscopic assisted restorative proctocolectomy and ileal pouch anal anastomosis (IPAA). PMID:26195886

Rectal metastasis from lobular breast carcinoma 15 years after primary diagnosis.

PubMed

López Deogracias, Maite; Flores Jaime, Laura; Arias-Camisón, Iñaki; Zamacola, Ilde; Murillo Guibert, Jesús; Suescun García, Rosa; Querejeta Usabiaga, Juan; Martínez García, Francisco

2010-02-01

Lobular breast carcinoma represents 2-20% of infiltrative carcinomas of the breast. The incidence of extrahepatic gastrointestinal (GI) tract metastases observed in necropsy studies varies from 6% to 18% and the most commonly affected organ is the stomach, followed by colon and rectum [1-4]. Reported herein is the case of a 67-year-old woman who was primarily diagnosed and surgically treated for a lobular carcinoma of the breast 15 years ago and is now referred with back pain and right hydronephrosis caused by a metastasis in rectum. Frequently, the absence of specific symptoms of digestive metastases of breast cancer leads to a misdiagnosis of this pathology [5-7]. The treatment will be based on a detailed clinical history and histopathological findings. Metastases from breast cancer in GI tract tumours must be excluded in a patient with previous history of breast carcinoma, as in the case reported herein.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shrotriya, D., E-mail: shrotriya2007@gmail.com; Srivastava, R. N. L.; Kumar, S.

The accurate dose delivery to the clinical target volume in radiotherapy can be affected by various pelvic tissues heterogeneities. An in-house heterogeneous woman pelvic phantom was designed and used to verify the consistency and computational capability of treatment planning system of radiation dose delivery in the treatment of cancer cervix. Oncentra 3D-TPS with collapsed cone convolution (CCC) dose calculation algorithm was used to generate AP/PA and box field technique plan. the radiation dose was delivered by Primus Linac (Siemens make) employing high energy 15 MV photon beam by isocenter technique. A PTW make, 0.125cc ionization chamber was used for directmore » measurements at various reference points in cervix, bladder and rectum. The study revealed that maximum variation between computed and measured dose at cervix reference point was 1% in both the techniques and 3% and 4% variation in AP/PA field and 5% and 4.5% in box technique at bladder and rectum points respectively.« less

A Cohort Mortality Study of Workers in a Second Soup Manufacturing Plant.

PubMed

Faramawi, Mohammed F; Ndetan, Harrison; Jadhav, Supriya; Johnson, Eric S

2015-01-01

The authors previously reported on mortality among workers in a Baltimore soup plant. Increased mortality was observed for cancers of the floor of the mouth, rectosigmoid colon/rectum/anus, epilepsy, and chronic nephritis. Here, the authors report on mortality on a second soup plant in the same locality. Excess mortality was similarly recorded for cancers of the tonsils/oropharynx, rectosigmoid colon/rectum/anus, and lung and myelofibrosis. Excess risk from cardiovascular, cerebrovascular, kidney, and infectious diseases was also observed. These 2 studies are important because firstly, to the authors' knowledge, they are the only reports of mortality in this occupational group in spite of their having a potential for exposure to hazardous carcinogenic agents. Secondly, there is no information on any exposure assessment in this industry. These 2 reports will draw attention to the need to conduct more detailed exposure and mortality investigations in this little-studied group.

[Anorectal Malignant Melanoma Is a Very Rare Disease and Has a Poor Prognosis].

PubMed

Yoshida, Yuta; Noura, Shingo; Matsumura, Tae; Hirota, Masaki; Shuto, Takashi; Muratsu, Arisa; Yasuyama, Harunobu; Takata, Akihiro; Koga, Chikato; Kameda, Chizu; Murakami, Masahiro; Kawabata, Ryohei; Shimizu, Junzo; Miwa, Hideaki; Hasegawa, Junichi

2017-11-01

We performed abdomino-perineal-resection(APR)on 2 cases of anorectal malignant melanoma. The first case was a 70- year-old woman suffering from bloody stool. Colonoscopy showed a black tumor in the rectum. Biopsy revealed a malignant melanoma. A CT scan showed multiple lung metastases and liver metastasis. She underwent surgery for the purpose of bleeding control, but died shortly thereafter because her liver and lung metastases had worsened. The second case was a 43- years-old man suffering from bloody stool. He had a black type 3 tumor in the rectum. A biopsy revealed malignant melanoma. A CT scan showed lateral lymph node swelling. He underwent APR with right side-lateral dissection. An established treatment for anorectal malignant melanoma has not been agreed upon and it is controversial. We experienced 2 cases that underwent surgery and we report them along with relevant information from the literature.

McKittrick-Wheelock syndrome - a rare cause of acute renal failure.

PubMed

Popescu, Alina; Orban-Schiopu, Ana-Maria; Becheanu, Gabriel; Diculescu, Mircea

2005-03-01

Fluid and electrolyte hypersecretion in the villous adenoma of the rectum is presented in the case of a 74 year old man presenting with a severe fluid imbalance. The patient had a 2-year history of mucous diarrhea and, on admission, presented prerenal uremia, hyponatremia and severe hypokalemia. At sigmoidoscopy, a 6/4 cm villous adenoma of the rectum was found. The increased loss of volume, followed by exhaustion of the physiological compensation mechanisms, led to a life-threatening hypokalemia, as well as to acute renal failure. Conservative treatment was followed by a temporary improvement of the renal function. Alternative treatment was: endocavitary irradiation, endoscopic resection and radical tumor surgery. The surgical removal of the adenoma led to complete recovery of the symptoms. The McKittrick-Wheelock syndrome can be a problem of difficult diagnosis, both for the gastroenterologist and also for the nephrologist. The patient may develop severe complications, which require a sustained treatment.

Chlamydia trachomatis proctitis masquerading as carcinoma rectum: First case report from India.

PubMed

Dhawan, Benu; Makharia, Govind Kumar; Juyal, Deepak; Sebastian, Sujeesh; Bhatia, Riti; Khanna, Neena

2017-01-01

While proctitis is caused both by infectious and noninfectious causes, infectious causes are acquired typically sexually. Chlamydia trachomatis, which is the most frequent bacterial pathogen causing sexually transmitted infections worldwide, is one of the causative agents of proctitis. We report a case history of a bisexual male who presented to us with rectal bleeding. The colonoscopy showed a nodular ulcerated lesion in the rectum suggestive of rectal malignancy, but biopsies from rectal mass did not reveal malignancy. A rectal biopsy was positive for C. trachomatis by polymerase chain reaction assay, and a diagnosis of C. trachomatis proctitis was made. Considering the invasive anorectal disease and patient's sexual history, he was treated with prolonged doxycycline therapy as per Centres for Disease Control and Prevention's treatment recommendation for lymphogranuloma venereum. A high index of clinical suspicion along with appropriate microbiological testing can clinch the diagnosis of C. trachomatis infection.

Defining probabilities of bowel resection in deep endometriosis of the rectum: Prediction with preoperative magnetic resonance imaging.

PubMed

Perandini, Alessio; Perandini, Simone; Montemezzi, Stefania; Bonin, Cecilia; Bellini, Gaia; Bergamini, Valentino

2018-02-01

Deep endometriosis of the rectum is a highly challenging disease, and a surgical approach is often needed to restore anatomy and function. Two kinds of surgeries may be performed: radical with segmental bowel resection or conservative without resection. Most patients undergo magnetic resonance imaging (MRI) before surgery, but there is currently no method to predict if conservative surgery is feasible or whether bowel resection is required. The aim of this study was to create an algorithm that could predict bowel resection using MRI images, that was easy to apply and could be useful in a clinical setting, in order to adequately discuss informed consent with the patient and plan the an appropriate and efficient surgical session. We collected medical records from 2010 to 2016 and reviewed the MRI results of 52 patients to detect any parameters that could predict bowel resection. Parameters that were reproducible and with a significant correlation to radical surgery were investigated by statistical regression and combined in an algorithm to give the best prediction of resection. The calculation of two parameters in MRI, impact angle and lesion size, and their use in a mathematical algorithm permit us to predict bowel resection with a positive predictive value of 87% and a negative predictive value of 83%. MRI could be of value in predicting the need for bowel resection in deep endometriosis of the rectum. Further research is required to assess the possibility of a wider application of this algorithm outside our single-center study. © 2017 Japan Society of Obstetrics and Gynecology.

[Local application of dimethyl sulfoxide at different concentrations to the prevention of radiation-induced damages in patient with cancer of the cervix uteri].

PubMed

Neklasova, N Iu; Sharinov, G M; Vinokurov, V L; Skrynditsa, G M

2006-01-01

to study the efficacy of dimethyl sulfoxide ((DMSO) at different concentrations in preventing radiation-induced rectal and urinary bladder damages in patients with cervix uteri cancer (CUC). combined radiation therapy (RT) was performed in 807 patients with CUC. In the control group (n = 221), RT was made, without applying radio-modified agents. An hour prior to a session of intracavitary irradiation, 10% DMSO solution was instilled into the rectum and urinary bladder in 113 patients and applications of metronidazole (MN) dissolved in 100% DSMO were made in 473 patients. Teleradiotherapy was performed, by using megavolt irradiation sources in the conventional fractionation mode; the total focal dose (TFD) was increased up to 40-46 Gy. Intracavitary irradiation was carried out on "AGAT-V" and "AGAT-VU" devices once weekly; the single focal dose in point A was 7 Gy; TFD was 49-56 Gy. 10% DMSO instillations reduced the incidence of late radiation-induced damages to the rectum and urinary bladder. In the control group, the incidence of these conditions was 19.0 and 9.5%, respectively; with the use of 10% DMSO, that was 8.8 and 7.1%. Applications of MN dissolved in 100% DMSO reduced the incidence of late radiation-induced damages to 1.7%. Local application of DMSO is a method for preventing late radiation-induced damages to the rectum and urinary bladder in patients with CUC. When the concentration of DMSO is increased, its preventive effect increases.

Cancer incidence in Spain, 2015.

PubMed

Galceran, J; Ameijide, A; Carulla, M; Mateos, A; Quirós, J R; Rojas, D; Alemán, A; Torrella, A; Chico, M; Vicente, M; Díaz, J M; Larrañaga, N; Marcos-Gragera, R; Sánchez, M J; Perucha, J; Franch, P; Navarro, C; Ardanaz, E; Bigorra, J; Rodrigo, P; Bonet, R Peris

2017-07-01

Periodic cancer incidence estimates of Spain from all existing population-based cancer registries at any given time are required. The objective of this study was to present the current situation of cancer incidence in Spain. The Spanish Network of Cancer Registries (REDECAN) estimated the numbers of new cancer cases occurred in Spain in 2015 by applying the incidence-mortality ratios method. In the calculus, incidence data from population-based cancer registries and mortality data of all Spain were used. In 2015, nearly a quarter of a million new invasive cancer cases were diagnosed in Spain, almost 149,000 in men (60.0%) and 99,000 in women. Globally, the five most common cancers were those of colon-rectum, prostate, lung, breast and urinary bladder. By gender, the four most common cancers in men were those of prostate (22.4%), colon-rectum (16.6%), lung (15.1%) and urinary bladder (11.7%). In women, the most common ones were those of breast (28.0%), colon-rectum (16.9%), corpus uteri (6.2%) and lung (6.0%). In recent years, cancer incidence in men seems to have stabilized due to the fact that the decrease in tobacco-related cancers compensates for the increase in other types of cancer like those of colon and prostate. In women, despite the stabilization of breast cancer incidence, increased incidence is due, above all, to the rise of colorectal and tobacco-related cancers. To reduce these incident cancer cases, improvement of smoking control policies and extension of colorectal cancer screening should be the two priorities in cancer prevention for the next years.

Is early detection of anastomotic leakage possible by intraperitoneal microdialysis and intraperitoneal cytokines after anterior resection of the rectum for cancer?

PubMed

Matthiessen, Peter; Strand, Ida; Jansson, Kjell; Törnquist, Cathrine; Andersson, Magnus; Rutegård, Jörgen; Norgren, Lars

2007-11-01

This prospective study assessed methods of detecting intraperitoneal ischemia and inflammatory response in patients with and without postoperative complications after anterior resection of the rectum. In 23 patients operated on with anterior resection of the rectum for rectal carcinoma, intraperitoneal lactate, pyruvate, and glucose levels were monitored postoperatively for six days by using microdialysis with catheters applied in two locations: intraperitoneally near the anastomosis, and in the central abdominal cavity. A reference catheter was placed subcutaneously in the pectoral region. Cytokines, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-alpha, were measured in intraperitoneal fluid by means of a pelvic drain for two postoperative days. The intraperitoneal lactate/pyruvate ratio near the anastomosis was higher on postoperative Day 5 (P = 0.029) and Day 6 (P = 0.009) in patients with clinical anastomotic leakage (n = 7) compared with patients without leakage (n = 16). The intraperitoneal levels of IL-6 (P = 0.002; P = 0.012, respectively) and IL-10 (P = 0.002; P = 0.041, respectively) were higher on postoperative Days 1 and 2 in the leakage group, and TNF-alpha was higher in the leakage group on Day 1 (P = 0.011). In-hospital clinical anastomotic leakage was diagnosed on median Day 6, and leakage after hospital discharge on median Day 20. The intraperitoneal lactate/pyruvate ratio and cytokines, IL-6, IL-10, and TNF-alpha, were increased in patients who developed symptomatic anastomotic leakage before clinical symptoms were evident.

Anorectal stimulation causes increased colonic motor activity in subjects with spinal cord injury.

PubMed

Korsten, Mark A; Singal, Ashwani K; Monga, Amit; Chaparala, Geeta; Khan, Amir M; Palmon, Ron; Mendoza, John Reagan D; Lirio, Juan P; Rosman, Alan S; Spungen, Ann; Bauman, William A

2007-01-01

Difficulty with evacuation (DWE) is a major problem after spinal cord injury (SCI). Stimulation of the anal canal and lower rectum, accomplished using a gloved finger (so-called digital rectal stimulation or DRS) is often used as an adjunct to laxatives and enemas to facilitate bowel evacuation. However, the basis for the efficacy of DRS is not known. This study assessed the effect of DRS on colonic motility. Six subjects with SCI were studied several hours after a bowel care session. Colonic motility was assessed using a manometric catheter (affixed endoscopically to the splenic flexure) at baseline, during DRS, and after DRS. In addition, evacuation of barium oatmeal paste (with the consistency of stool and introduced into the rectum and descending colon) was assessed simultaneously using fluoroscopic techniques. The mean number (+/- SEM) of peristaltic waves per minute increased from 0 at baseline to 1.9 (+/- 0.5/min) during DRS and 1.5 (+/- 0.3/min) during the period immediately after cessation of DRS (P < 0.05). The mean amplitude (+/- SEM) of the peristaltic contractions was 43.4 (+/- 2.2) mmHg. The frequency of contractions, as well as amplitude of contractions, during or immediately after DRS was not significantly different. These manometric changes in response to DRS were accompanied by expulsion of barium oatmeal paste in every subject by the fifth DRS. DRS causes left-sided colonic activity in subjects with SCI. At least in part, an anorectal colonic reflex that results in enhanced contractions of the descending colon and rectum may contribute to bowel evacuation in individuals with SCI.

High rates of intestinal bicarbonate secretion in seawater tilapia (Oreochromis mossambicus).

PubMed

Ruiz-Jarabo, I; Gregório, S F; Gaetano, P; Trischitta, F; Fuentes, J

2017-05-01

Osmoregulation in fish is a complex process that requires the orchestrated cooperation of many tissues. In fish facing hyperosmotic environments, the intestinal absorption of some monovalent ions and the secretion of bicarbonate are key processes to favor water absorption. In the present study, we showed that bicarbonate levels in the intestinal fluid are several fold higher in seawater than in freshwater acclimated tilapia (Oreochromis mossambicus). In addition, we analyzed gene expression of the main molecular mechanisms involved in HCO 3 - movements i.e. slc26a6, slc26a3, slc4a4 and v-type H-ATPase sub C in the intestine of tilapia acclimated to both seawater and freshwater. Our results show an anterior/posterior functional regionalization of the intestine in tilapia in terms of expression patterns, which is affected by environmental salinity mostly in the anterior and mid intestine. Analysis of bicarbonate secretion using pH-Stat in tissues mounted in Ussing chambers reveals high rates of bicarbonate secretion in tilapia acclimated to seawater from anterior intestine to rectum ranging between ~900 and ~1700nmolHCO 3 - cm -2 h -1 . However, a relationship between the expression of slc26a6, slc26a3, slc4a4 and the rate of bicarbonate secretion seems to be compromised in the rectum. In this region, the low expression of the bicarbonate transporters could not explain the high bicarbonate secretion rates here described. However, we postulate that the elevated v-type H-ATPase mRNA expression in the rectum could be involved in this process. Copyright © 2017 Elsevier Inc. All rights reserved.

Automated registration of large deformations for adaptive radiation therapy of prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Godley, Andrew; Ahunbay, Ergun; Peng Cheng

2009-04-15

Available deformable registration methods are often inaccurate over large organ variation encountered, for example, in the rectum and bladder. The authors developed a novel approach to accurately and effectively register large deformations in the prostate region for adaptive radiation therapy. A software tool combining a fast symmetric demons algorithm and the use of masks was developed in C++ based on ITK libraries to register CT images acquired at planning and before treatment fractions. The deformation field determined was subsequently used to deform the delivered dose to match the anatomy of the planning CT. The large deformations involved required that themore » bladder and rectum volume be masked with uniform intensities of -1000 and 1000 HU, respectively, in both the planning and treatment CTs. The tool was tested for five prostate IGRT patients. The average rectum planning to treatment contour overlap improved from 67% to 93%, the lowest initial overlap is 43%. The average bladder overlap improved from 83% to 98%, with a lowest initial overlap of 60%. Registration regions were set to include a volume receiving 4% of the maximum dose. The average region was 320x210x63, taking approximately 9 min to register on a dual 2.8 GHz Linux system. The prostate and seminal vesicles were correctly placed even though they are not masked. The accumulated doses for multiple fractions with large deformation were computed and verified. The tool developed can effectively supply the previously delivered dose for adaptive planning to correct for interfractional changes.« less

Applying the precautionary principle to nutrition and cancer.

PubMed

Gonzales, Joseph F; Barnard, Neal D; Jenkins, David J A; Lanou, Amy J; Davis, Brenda; Saxe, Gordon; Levin, Susan

2014-01-01

Research has identified certain foods and dietary patterns that are associated with reduced cancer risk and improved survival after cancer diagnosis. This research has formed the basis for dietary guidance issued by cancer organizations. Unfortunately, gaps within nutrition research have made it difficult to make recommendations in some areas. This review specifies suggested dietary guidance in which evidence of a dietary influence on cancer risk is substantial, even if not conclusive. Evidence summaries within the review are based on the 2007 report of the World Cancer Research Fund/American Institute for Cancer Research. This review also describes advantages and disadvantages of following the suggested dietary guidance and includes putative mechanisms involved in cancer progression. Suggested dietary guidance where evidence is sufficiently compelling include (1) limiting or avoiding dairy products to reduce the risk of prostate cancer; (2) limiting or avoiding alcohol to reduce the risk of cancers of the mouth, pharynx, larynx, esophagus, colon, rectum, and breast; (3) avoiding red and processed meat to reduce the risk of cancers of the colon and rectum; (4) avoiding grilled, fried, and broiled meats to reduce the risk of cancers of the colon, rectum, breast, prostate, kidney, and pancreas; (5) consumption of soy products during adolescence to reduce the risk of breast cancer in adulthood and to reduce the risk of recurrence and mortality for women previously treated for breast cancer; and (6) emphasizing fruits and vegetables to reduce risk of several common forms of cancer. By adopting the precautionary principle for nutrition research, this review aims to serve as a useful tool for practitioners and patients.

Iterative-cuts: longitudinal and scale-invariant segmentation via user-defined templates for rectosigmoid colon in gynecological brachytherapy

PubMed Central

Lüddemann, Tobias; Egger, Jan

2016-01-01

Abstract. Among all types of cancer, gynecological malignancies belong to the fourth most frequent type of cancer among women. In addition to chemotherapy and external beam radiation, brachytherapy is the standard procedure for the treatment of these malignancies. In the progress of treatment planning, localization of the tumor as the target volume and adjacent organs of risks by segmentation is crucial to accomplish an optimal radiation distribution to the tumor while simultaneously preserving healthy tissue. Segmentation is performed manually and represents a time-consuming task in clinical daily routine. This study focuses on the segmentation of the rectum/sigmoid colon as an organ-at-risk in gynecological brachytherapy. The proposed segmentation method uses an interactive, graph-based segmentation scheme with a user-defined template. The scheme creates a directed two-dimensional graph, followed by the minimal cost closed set computation on the graph, resulting in an outlining of the rectum. The graph’s outline is dynamically adapted to the last calculated cut. Evaluation was performed by comparing manual segmentations of the rectum/sigmoid colon to results achieved with the proposed method. The comparison of the algorithmic to manual result yielded a dice similarity coefficient value of 83.85±4.08, in comparison to 83.97±8.08% for the comparison of two manual segmentations by the same physician. Utilizing the proposed methodology resulted in a median time of 128  s/dataset, compared to 300 s needed for pure manual segmentation. PMID:27403448

Evaluation of prophylactic and therapeutic effects of ruscogenin on acute radiation proctitis: an experimental rat model.

PubMed

Yavuz, Erkan; Karagulle, Onur Olgac; Ercan, Gulcin; Celik, Atilla; Yigitbas, Hakan; Bayrak, Busra Yaprak; Tartar, Rumeysa; Kusaslan, Ramazan; Altinel, Yuksel; Gulcicek, Osman Bilgin

2018-04-01

Radiation proctitis (RP) is inflammation and damage to the rectum, manifested secondary to ionizing radiation utilized for treatment. In this study, we evaluated the anti-inflammatory therapeutical and protective effects of ruscogenin in a model of acute RP. Thirty-two Sprague-Dawley rats were divided into 4 groups (n = 8) as sham, control, treatment, and prophylaxis groups. Prophylaxis group and treatment group were dosed ruscogenin by oral gavage for 14 days pre- and postradiation. At the end of the 28th day, all subjects were sacrificed. Histopathological analysis showed a significant increase in cryptitis abscess, cryptitis and reactive atypia, and depth of lymphocytic infiltration of the control group, compared to the other groups (P < 0.05), while treatment and prophylaxis groups showed significant decreases (P < 0.05). Immunohistochemical analysis indicated that immunoreactivity were significantly higher in control group (P < 0.05, P < 0.001, and P < 0.01, respectively), but vice versa for treatment and prophylaxis groups. There was not any significant difference for fibroblast growth factor 2 immunoreactivity. The epithelium of control rectums indicated an increase in TNF-α immunoreactivity while other groups had significant decrease (P < 0.01). Electron microscopical findings were parallel to light microscopy. In this study, ruscogenin was observed to be effective on prophylaxis or treatment of acute RP. Although there are various reports on the treatment of the rectum damaged by acute RP in the literature, this could be the first study since there is no research indicating the ultrastructural effect of ruscogenin.

Intermediate-term results of image-guided brachytherapy and high-technology external beam radiotherapy in cervical cancer: Chiang Mai University experience.

PubMed

Tharavichitkul, Ekkasit; Chakrabandhu, Somvilai; Wanwilairat, Somsak; Tippanya, Damrongsak; Nobnop, Wannapha; Pukanhaphan, Nantaka; Galalae, Razvan M; Chitapanarux, Imjai

2013-07-01

To evaluate the outcomes of image-guided brachytherapy combined with 3D conformal or intensity modulated external beam radiotherapy (3D CRT/IMRT) in cervical cancer at Chiang Mai University. From 2008 to 2011, forty-seven patients with locally advanced cervical cancer were enrolled in this study. All patients received high-technology (3D CRT/IMRT) whole pelvic radiotherapy with a total dose of 45-46 Gy plus image-guided High-Dose-Rate intracavitary brachytherapy 6.5-7 Gy × 4 fractions to a High-Risk Clinical Target Volume (HR-CTV) according to GEC-ESTRO recommendations. The dose parameters of the HR-CTV for bladder, rectum and sigmoid colon were recorded, as well as toxicity profiles. In addition, the endpoints for local control, disease-free, metastasis-free survival and overall survival were calculated. At the median follow-up time of 26 months, the local control, disease-free survival, and overall survival rates were 97.9%, 85.1%, and 93.6%, respectively. The mean dose of HR-CTV, bladder, rectum and sigmoid were 93.1, 88.2, 69.6, and 72 Gy, respectively. In terms of late toxicity, the incidence of grade 3-4 bladder and rectum morbidity was 2.1% and 2.1%, respectively. A combination of image-guided brachytherapy and IMRT/3D CRT showed very promising results of local control, disease-free survival, metastasis-free survival and overall survival rates. It also caused a low incidence of grade 3-4 toxicity in treated study patients. Copyright © 2013 Elsevier Inc. All rights reserved.

Repeatability and accuracy of reproductive tract scoring to determine pubertal status in beef heifers.

PubMed

Rosenkrans, Kelly S; Hardin, David K

2003-03-01

The objective of this study was to compare the repeatability and accuracy of palpation per rectum to transrectal ultrasonography and serum progesterone concentrations for determining pubertal status in beef heifers. One hundred and seventy-four rectal examinations were performed on 29 predominantly Angus heifers by two veterinarians (A and B) and assigned individual reproductive tract scores (RTS) during monthly examinations over a 3-month period. Heifers were examined in the morning by both veterinarians, randomized, and re-examined in the afternoon. The size and location of ovarian structures of each heifer were determined by ultrasonography. Heifers with follicles >10mm in diameter or corpora lutea were classified as pubertal. Serum progesterone concentrations at the time of the examination and 10 days later were determined by radioimmunoassay and used to classify heifers as prepubertal (<1 ng/ml in both samples) or pubertal (at least one sample >or=1 ng/ml). Kappa, which describes degree of agreement beyond chance, was used to determine repeatability of the RTS system. Multicategory Kappa for agreement was 0.64 within veterinarian, 0.46 between veterinarian, and 0.35 between palpation per rectum and transrectal ultrasonography. Sensitivity and specificity of palpation per rectum for diagnosis of pubertal status compared to serum progesterone levels were higher (82 and 69%, respectively) than sensitivity and specificity of ultrasonography (79 and 59%, respectively). This study validates the RTS system as a repeatable and accurate screening test to evaluate pubertal status in groups of heifers prior to the onset of the breeding season.

Improved access and visibility during stapling of the ultra-low rectum: a comparative human cadaver study between two curved staplers

PubMed Central

2012-01-01

Background The purpose of this study was to compare in human cadavers the applicability of a commonly used stapling device, the CONTOUR® curved cutter (CC) (Ethicon Endo-Surgery, Cincinnati, OH) to a newly released, curved stapler, the Endo GIA™ Radial Reload with Tri-Staple™ Technology (RR) (Covidien, New Haven, CT) Methods Four experienced surgeons performed deep pelvic dissection with total mesorectal excision (TME) of the rectum in twelve randomized male cadavers. Both stapling devices were applied to the ultra-low rectum in coronal and sagittal configurations. Extensive measurements were recorded of anatomic landmarks for each cadaver pelvis along with various aspects of access, visibility, and ease of placement for each device. Results The RR reached significantly lower into the pelvis in both the coronal and sagittal positions compared to the CC. The median distance from the pelvic floor was 1.0 cm compared to 2.0 cm in the coronal position, and 1.0 cm versus 3.3 cm placed sagitally, p < 0.0001. Surgeons gave a higher visibility rating with less visual impediment in the sagittal plane using the RR Stapler. Impediment of visibility occurred in only 10% (5/48) of RR applications in the coronal position, compared to a rate of 48% (23/48) using the CC, p = 0.0002. Conclusions The RR device performed significantly better when compared to the CC stapler in regards to placing the stapler further into the deep pelvis and closer to the pelvic floor, while causing less obstructing of visualization. PMID:23148602

Assessment of accuracy and efficiency of atlas-based autosegmentation for prostate radiotherapy in a variety of clinical conditions.

PubMed

Simmat, I; Georg, P; Georg, D; Birkfellner, W; Goldner, G; Stock, M

2012-09-01

The goal of the current study was to evaluate the commercially available atlas-based autosegmentation software for clinical use in prostate radiotherapy. The accuracy was benchmarked against interobserver variability. A total of 20 planning computed tomographs (CTs) and 10 cone-beam CTs (CBCTs) were selected for prostate, rectum, and bladder delineation. The images varied regarding to individual (age, body mass index) and setup parameters (contrast agent, rectal balloon, implanted markers). Automatically created contours with ABAS(®) and iPlan(®) were compared to an expert's delineation by calculating the Dice similarity coefficient (DSC) and conformity index. Demo-atlases of both systems showed different results for bladder (DSC(ABAS) 0.86 ± 0.17, DSC(iPlan) 0.51 ± 0.30) and prostate (DSC(ABAS) 0.71 ± 0.14, DSC(iPlan) 0.57 ± 0.19). Rectum delineation (DSC(ABAS) 0.78 ± 0.11, DSC(iPlan) 0.84 ± 0.08) demonstrated differences between the systems but better correlation of the automatically drawn volumes. ABAS(®) was closest to the interobserver benchmark. Autosegmentation with iPlan(®), ABAS(®) and manual segmentation took 0.5, 4 and 15-20 min, respectively. Automatic contouring on CBCT showed high dependence on image quality (DSC bladder 0.54, rectum 0.42, prostate 0.34). For clinical routine, efforts are still necessary to either redesign algorithms implemented in autosegmentation or to optimize image quality for CBCT to guarantee required accuracy and time savings for adaptive radiotherapy.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, R; Zhu, X; Li, S

Purpose: High Dose Rate (HDR) brachytherapy forward planning is principally an iterative process; hence, plan quality is affected by planners’ experiences and limited planning time. Thus, this may lead to sporadic errors and inconsistencies in planning. A statistical tool based on previous approved clinical treatment plans would help to maintain the consistency of planning quality and improve the efficiency of second checking. Methods: An independent dose calculation tool was developed from commercial software. Thirty-three previously approved cervical HDR plans with the same prescription dose (550cGy), applicator type, and treatment protocol were examined, and ICRU defined reference point doses (bladder, vaginalmore » mucosa, rectum, and points A/B) along with dwell times were collected. Dose calculation tool then calculated appropriate range with a 95% confidence interval for each parameter obtained, which would be used as the benchmark for evaluation of those parameters in future HDR treatment plans. Model quality was verified using five randomly selected approved plans from the same dataset. Results: Dose variations appears to be larger at the reference point of bladder and mucosa as compared with rectum. Most reference point doses from verification plans fell between the predicted range, except the doses of two points of rectum and two points of reference position A (owing to rectal anatomical variations & clinical adjustment in prescription points, respectively). Similar results were obtained for tandem and ring dwell times despite relatively larger uncertainties. Conclusion: This statistical tool provides an insight into clinically acceptable range of cervical HDR plans, which could be useful in plan checking and identifying potential planning errors, thus improving the consistency of plan quality.« less

Study of the role of the transverse perineal muscles during rectal filling.

PubMed

Shafik, Ahmed; Shafik, Ali A; Shafik, Ismail; El-Sibai, Olfat

2006-10-01

The function of perineal muscles at defecation is poorly addressed in the literature. We investigated the hypothesis that rectal distension effects reflex contraction of four perineal muscles. After rectal balloon distension with carbon dioxide in increments of 20 ml, the responses of electromyographic (EMG) activity of superficial (STPM) and deep (DTPM) transverse perineal muscles as well as the rectal pressure were recorded in 22 healthy volunteers (14 men, age 37.2+/-6.3 years). Responses were registered again after individual anesthetization of rectum and transverse perineal muscles. Tests were repeated using saline instead of lidocaine. Rectal balloon distension in big volumes effected increase of the transverse perineal muscles' EMG activity and rectal pressure. The more the rectum was distended, the more the rectal pressure and EMG activity of the transverse perineal muscles were increased. The latency showed a gradual decrease upon incremental rectal distension increase. Transverse perineal muscles did not respond to rectal distension after the rectum and perineal muscles had been individually anesthetized, but it responded to saline administration. Response of the muscles was similar in both sides. Increase of rectal pressure increases EMG activity of transverse perineal muscles. This action seems mediated through a reflex which we call 'recto-perineal reflex'. Contraction of transverse perineal muscles at defecation presumably supports the perineal floor. It also protects transverse perineal muscles against straining-produced high pressure that is transmitted through the recto-vaginal/-vesical cul de sac to the perineum which may sag down and share in genesis of perineocele, enterocele, or sigmoidocele.

The effect of tandem-ovoid titanium applicator on points A, B, bladder, and rectum doses in gynecological brachytherapy using 192Ir.

PubMed

Sadeghi, Mohammad Hosein; Sina, Sedigheh; Mehdizadeh, Amir; Faghihi, Reza; Moharramzadeh, Vahed; Meigooni, Ali Soleimani

2018-02-01

The dosimetry procedure by simple superposition accounts only for the self-shielding of the source and does not take into account the attenuation of photons by the applicators. The purpose of this investigation is an estimation of the effects of the tandem and ovoid applicator on dose distribution inside the phantom by MCNP5 Monte Carlo simulations. In this study, the superposition method is used for obtaining the dose distribution in the phantom without using the applicator for a typical gynecological brachytherapy (superposition-1). Then, the sources are simulated inside the tandem and ovoid applicator to identify the effect of applicator attenuation (superposition-2), and the dose at points A, B, bladder, and rectum were compared with the results of superposition. The exact dwell positions, times of the source, and positions of the dosimetry points were determined in images of a patient and treatment data of an adult woman patient from a cancer center. The MCNP5 Monte Carlo (MC) code was used for simulation of the phantoms, applicators, and the sources. The results of this study showed no significant differences between the results of superposition method and the MC simulations for different dosimetry points. The difference in all important dosimetry points was found to be less than 5%. According to the results, applicator attenuation has no significant effect on the calculated points dose, the superposition method, adding the dose of each source obtained by the MC simulation, can estimate the dose to points A, B, bladder, and rectum with good accuracy.

The Lactobacillus flora in vagina and rectum of fertile and postmenopausal healthy Swedish women

PubMed Central

2011-01-01

Background Lactobacillus species are the most often found inhabitants of vaginal ecosystem of fertile women. In postmenopausal women with low oestrogen levels, Lactobacillus flora is diminishing or absent. However, no studies have been performed to investigate the correlation between oestrogen levels and the lactobacilli in the gut. The aim of the present study was to investigate the relation in healthy women between vaginal and rectal microbial flora as well as possible variations with hormone levels. Methods Vaginal and rectal smears were taken from 20 healthy fertile women, average 40 years (range 28-49 years), in two different phases of the menstrual cycle, and from 20 postmenopausal women, average 60 years (range 52-85 years). Serum sex hormone levels were analyzed. Bacteria from the smears isolated on Rogosa Agar were grouped by Randomly Amplified Polymorphic DNA and identified by multiplex PCR and partial 16S rRNA gene sequencing. Results Lactobacillus crispatus was more often found in the vaginal flora of fertile women than in that of postmenopausal (p = 0.036). Fifteen of 20 fertile women had lactobacilli in their rectal smears compared to 10 postmenopausal women (p = 0.071). There was no correlation between the number of bacteria in vagina and rectum, or between the number of bacteria and hormonal levels. Neither could any association between the presence of rectal lactobacilli and hormonal levels be found. Conclusion Lactobacillus crispatus was more prevalent in the vaginal flora of fertile women, whereas the Lactobacillus flora of rectum did not correlate to the vaginal flora nor to hormonal levels. PMID:21609500

Cancers Associated with Overweight and Obesity Infographic

Cancer.gov

Overweight and obesity are linked to an increased risk of 13 types of cancer. See a diagram of the human body highlighting the organs or tissues at increased cancer risk, including the breast, colon and rectum, kidney, and liver.

Long-term functional outcomes following colorectal resection versus shaving for rectal endometriosis.

PubMed

Roman, Horace; Milles, Mathilde; Vassilieff, Maud; Resch, Benoit; Tuech, Jean-Jacques; Huet, Emmanuel; Darwish, Basma; Abo, Carole

2016-12-01

Two surgical approaches usually are used in the surgical management of deep infiltrating endometriosis of the rectum: the radical approach that mainly is based on colorectal resection and the conservative or symptom-guided approach that prioritizes conservation of the rectum. There are no data available that compare long-term functional digestive outcomes of 1 approach to the other. The purpose of this study was to compare long-term digestive outcomes in women who were treated by either rectal shaving or colorectal resection for deep endometriosis infiltrating the rectum. A retrospective comparative study was performed. All women who were treated with surgery for deep endometriosis infiltrating the rectum by either shaving or colorectal resection at the University Hospital of Rouen from January 2005 to January 2010 were enrolled. Follow-up evaluation was carried out for a minimum of 5 years. Postoperative evaluation of digestive symptoms was performed by 4 standardized gastrointestinal questionnaires: the Gastrointestinal Quality of Life Index, the Knowles-Eccersley-Scott-Symptom score for constipation, the Wexner score for anal continence, and the Bristol Stool Score. Symptoms that were related to endometriosis, fertility, and disease recurrence were obtained from a specific questionnaire. A total of 77 women were included. Three women were lost to follow up (3.9%), and 3 were treated by disc excision (3.9%). The mean follow-up time was 80±19 months. Forty-six women underwent conservative rectal shaving, and 25 women underwent colorectal resection. Patient characteristics and the severity of the disease were comparable in both groups. Patients who were treated by rectal shaving had significantly better Gastrointestinal Quality of Life Index values, lower Knowles-Eccersley-Scott-Symptom scores for postoperative constipation, and better anal continence. No statistically significant differences were revealed for postoperative pelvic pain. Rectal recurrence occurred in 8.7% of patients who were treated by conservative surgery: 4.3% underwent secondary colorectal resection and 4.3% were treated secondarily by rectal shaving. Consequently, avoiding a recurrence for merely 1 patient would have required 11 patients to undergo colorectal resection instead of shaving. Our data suggest that, in patients who are treated for rectal endometriosis, colorectal resection does not improve long-term postoperative functional outcomes when compared with rectal shaving. Copyright © 2016 Elsevier Inc. All rights reserved.

Prognostic importance of gram-negative intestinal colonization preceding pancreatic infection in severe acute pancreatitis. Results of a controlled clinical trial of selective decontamination.

PubMed

Luiten, E J; Hop, W C; Endtz, H P; Bruining, H A

1998-05-01

To establish, firstly, whether gram-negative (re)-colonization of the gut leads to an increased risk of gram-negative pancreatic infections and whether this event is time-related and, secondly, whether the difference in the quantity and quality of micro-organisms colonizing the digestive tract influences morbidity and mortality. Prospective analysis of the results of systematic semi-quantitative cultures of several body areas taken from patients with severe acute pancreatitis, during a controlled multicenter trial of adjuvant selective decontamination. Surgical intensive care units of 16 hospitals. A total of 2,159 semi-quantitative cultures from the oropharynx, rectum and pancreatic tissues taken from 90 patients were analyzed. Surveillance cultures from the oropharynx and rectum were taken on admission and repeated twice weekly and from the (peri)-pancreatic devitalized tissues (i. e. necrosis) at every relaparotomy and from drainage. All gram-negative pancreatic infections were preceded by intestinal colonization with the same micro-organisms. The risk of developing a pancreatic infection following gram-negative intestinal colonization (15/42 patients) was significantly higher as compared to patients without gram-negative colonization (0/10 patients) (p < 0.001) or to patients in whom E. coli was the only intestinal micro-organism cultured (0/30 patients) (p < 0.001). The occurrence of intestinal E. coli did not increase the risk of pancreatic infection. Gram-negative colonization of the rectum and oropharynx significantly correlated with the later development of pancreatic infection: relative risks 73.7 (p < 0.001) and 13.6 (p < 0.001), respectively. However, when both areas were evaluated simultaneously, the rectum was more significant (p < 0.001). The severity of intestinal intestinal colonization until the moment of pancreatic infection showed an increase in time in all 15 patients. In 11 of 15 patients (73%) these infections occurred within 1 week following the first isolation from the digestive tract. Gram-negative intestinal colonization was associated with a 3.7 fold increased mortality risk (p = 0.004). Gram-negative intestinal colonization, E. coli excepted, is an early prognostic parameter in patients in whom pancreatic infection has not yet occurred and represents a significantly increased risk of pancreatic infections and mortality.

Predictors of Toxicity After Image-guided High-dose-rate Interstitial Brachytherapy for Gynecologic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Larissa J.; Viswanathan, Akila N., E-mail: aviswanathan@lroc.harvard.edu

2012-12-01

Purpose: To identify predictors of grade 3-4 complications and grade 2-4 rectal toxicity after three-dimensional image-guided high-dose-rate (HDR) interstitial brachytherapy for gynecologic cancer. Methods and Materials: Records were reviewed for 51 women (22 with primary disease and 29 with recurrence) treated with HDR interstitial brachytherapy. A single interstitial insertion was performed with image guidance by computed tomography (n = 43) or magnetic resonance imaging (n = 8). The median delivered dose in equivalent 2-Gy fractions was 72.0 Gy (45 Gy for external-beam radiation therapy and 24 Gy for brachytherapy). Toxicity was reported according to the Common Toxicity Criteria for Adversemore » Events. Actuarial toxicity estimates were calculated by the Kaplan-Meier method. Results: At diagnosis, the median patient age was 62 years and the median tumor size was 3.8 cm. The median D90 and V100 were 71.4 Gy and 89.5%; the median D2cc for the bladder, rectum, and sigmoid were 64.6 Gy, 61.0 Gy, and 52.7 Gy, respectively. The actuarial rates of all grade 3-4 complications at 2 years were 20% gastrointestinal, 9% vaginal, 6% skin, 3% musculoskeletal, and 2% lymphatic. There were no grade 3-4 genitourinary complications and no grade 5 toxicities. Grade 2-4 rectal toxicity was observed in 10 patients, and grade 3-4 complications in 4; all cases were proctitis with the exception of 1 rectal fistula. D2cc for rectum was higher for patients with grade 2-4 (68 Gy vs 57 Gy for grade 0-1, P=.03) and grade 3-4 (73 Gy vs 58 Gy for grade 0-2, P=.02) rectal toxicity. The estimated dose that resulted in a 10% risk of grade 2-4 rectal toxicity was 61.8 Gy (95% confidence interval, 51.5-72.2 Gy). Discussion: Image-guided HDR interstitial brachytherapy results in acceptable toxicity for women with primary or recurrent gynecologic cancer. D2cc for the rectum is a reliable predictor of late rectal complications. Three-dimensional-based treatment planning should be performed to ensure adequate tumor coverage while minimizing the D2cc to the rectum.« less

Can a curved stapler made for open surgery be useful in laparoscopic lower rectal resections? Technique and experience of a single centre.

PubMed

Mari, Francesco Saverio; Gasparrini, Marcello; Nigri, Giuseppe; Berardi, Giammauro; Laracca, Giovanni Guglielmo; Flora, Barbara; Pancaldi, Alessandra; Brescia, Antonio

2013-01-01

The use of laparoscopy to perform lower anterior rectal resection is increasing worldwide because it allows better visualisation and rectal mobilisation and also reduces postoperative pain and recovery. The Contour Curved Stapler (CCS) is a very helpful device because of its curved profile that enables better access into the pelvic cavity and allows rectal closure and section to be performed in one shot. In this paper, we present an original technique to use this device, made for open surgery, in laparoscopy and the results of our experience. We retrospectively evaluated the data of all patients who underwent lower laparoscopic anterior rectal resection and in which the CCS was used to perform section of the rectum between September 2005 and September 2011. To perform section of the rectum a Lapdisc(®) was inserted through a 6-7 cm supra-pubic midline incision to allow placement of the CCS into the pelvic cavity. Patients' biographical and surgical data such as sex, age, indication for surgery, infection, anastomotic leakage or stenosis and staple-line bleeding were prospectively collected in a computerised database and evaluated. Between September 2005 and September 2011, we performed 45 laparoscopic lower rectal resection using CCS, 27 male and 18 female with a mean age of 61 years (range 40-82 years) and a mean body mass index (BMI) of 26.5 kg/m(2) (range 16.5-35 kg/m(2)). In 29 cases a temporary ileostomy was performed. Mean operative time was 131 min (range 97-210 min). In all cases it was possible to perform a lower section of the rectum with CCS. No intraoperative or postoperative staple line bleeding occurred. In two patients we observed anastomotic leaks and in one of these a temporary ileostomy was performed. None of the patients showed an anastomotic stenosis at 1-year follow-up colonoscopy. This study shows that CCS enables section of the lower rectum to be easily performed, especially in adverse anatomical condition, and the technique proposed by us allows the use of this stapler without giving up the benefits of laparoscopic access. Copyright © 2012 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

SU-F-T-36: Dosimetric Comparison of Point Based Vs. Target Based Prescription for Intracavitary Brachytherapy in Cancer of the Cervix

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ashenafi, M; McDonald, D; Peng, J

Purpose: Improved patient imaging used for planning the treatment of cervical cancer with Tandem and Ovoid (T&O) Intracavitary high-dose-rate brachytherapy (HDR) now allows for 3D delineation of target volumes and organs-at-risk. However, historical data relies on the conventional point A-based planning technique. A comparative dosimetric study was performed by generating both target-based (TBP) and point-based (PBP) plans for ten clinical patients. Methods: Treatment plans created using Elekta Oncentra v. 4.3 for ten consecutive cervical cancer patients were analyzed. All patients were treated with HDR using the Utrecht T&O applicator. Both CT and MRI imaging modalities were utilized to delineate clinicalmore » target volume (CTV) and organs-at-risk (rectum, sigmoid, bladder, and small bowel). Point A (left and right), vaginal mucosa, and ICRU rectum and bladder points were defined on CT. Two plans were generated for each patient using two prescription methods (PBP and TBP). 7Gy was prescribed to each point A for each PBP plan and to the target D90% for each TBP plan. Target V90%, V100%, and V200% were evaluated. In addition, D0.1cc and D2cc were analyzed for each organ-at-risk. Differences were assessed for statistical significance (p<0.05) by use of Student’s t-test. Results: Target coverage was comparable for both planning methods, with each method providing adequate target coverage. TBP showed lower absolute dose to the target volume than PBP (D90% = 7.0Gy vs. 7.4Gy, p=0.028), (V200% = 10.9cc vs. 12.8cc, p=0.014), (ALeft = 6.4Gy vs. 7Gy, p=0.009), and (ARight = 6.4Gy vs. 7Gy, p=0.013). TBP also showed a statistically significant reduction in bladder, rectum, small bowel, and sigmoid doses compared to PBP. There was no statistically significant difference in vaginal mucosa or ICRU-defined rectum and bladder dose. Conclusion: Target based prescription resulted in substantially lower dose to delineated organs-at-risk compared to point based prescription, while maintaining similar target coverage.« less

Conservative surgery versus colorectal resection in deep endometriosis infiltrating the rectum: a randomized trial

PubMed Central

Bubenheim, Michael; Huet, Emmanuel; Bridoux, Valérie; Zacharopoulou, Chrysoula; Daraï, Emile; Collinet, Pierre; Tuech, Jean-Jacques

2018-01-01

Abstract STUDY QUESTION Is there a difference in functional outcome between conservative versus radical rectal surgery in patients with large deep endometriosis infiltrating the rectum 2 years postoperatively? SUMMARY ANSWER No evidence was found that functional outcomes differed when conservative surgery was compared to radical rectal surgery for deeply invasive endometriosis involving the bowel. WHAT IS KNOWN ALREADY Adopting a conservative approach to the surgical management of deep endometriosis infiltrating the rectum, by employing shaving or disc excision, appears to yield improved digestive functional outcomes. However, previous comparative studies were not randomized, introducing a possible bias regarding the presumed superiority of conservative techniques due to the inclusion of patients with more severe deep endometriosis who underwent colorectal resection. STUDY DESIGN SIZE, DURATION From March 2011 to August 2013, we performed a 2-arm randomized trial, enroling 60 patients with deep endometriosis infiltrating the rectum up to 15 cm from the anus, measuring more than 20 mm in length, involving at least the muscular layer in depth and up to 50% of rectal circumference. No women were lost to follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS Patients were enroled in three French university hospitals and had either conservative surgery, by shaving or disc excision, or radical rectal surgery, by segmental resection. Randomization was performed preoperatively using sequentially numbered, opaque, sealed envelopes, and patients were informed of the results of randomization. The primary endpoint was the proportion of patients experiencing one of the following symptoms: constipation (1 stool/>5 consecutive days), frequent bowel movements (≥3 stools/day), defecation pain, anal incontinence, dysuria or bladder atony requiring self-catheterization 24 months postoperatively. Secondary endpoints were the values of the Visual Analog Scale (VAS), Knowles–Eccersley–Scott-Symptom Questionnaire (KESS), the Gastrointestinal Quality of Life Index (GIQLI), the Wexner scale, the Urinary Symptom Profile (USP) and the Short Form 36 Health Survey (SF36). MAIN RESULTS AND THE ROLE OF CHANCE A total of 60 patients were enroled. Among the 27 patients in the conservative surgery arm, two were converted to segmental resection (7.4%). In each group, 13 presented with at least one functional problem at 24 months after surgery (48.1 versus 39.4%, OR = 0.70, 95% CI 0.22–2.21). The intention-to-treat comparison of the overall scores on KESS, GIQLI, Wexner, USP and SF36 did not reveal significant differences between the two arms. Segmental resection was associated with a significant risk of bowel stenosis. LIMITATIONS REASONS FOR CAUTION The inclusion of only large infiltrations of the rectum does not allow the extrapolation of conclusions to small nodules of <20 mm in length. The presumption of a 40% difference favourable to conservative surgery in terms of postoperative functional outcomes resulted in a lack of power to demonstrate a difference for the primary endpoint. WIDER IMPLICATIONS OF THE FINDINGS Conservative surgery is feasible in patients managed for large deep rectal endometriosis. The trial does not show a statistically significant superiority of conservative surgery for mid-term functional digestive and urinary outcomes in this specific population of women with large involvement of the rectum. There is a higher risk of rectal stenosis after segmental resection, requiring additional endoscopic or surgical procedures. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by a grant from the clinical research programme for hospitals (PHRC) in France. The authors declare no competing interests related to this study. TRIAL REGISTRATION NUMBER This study is registered with ClinicalTrials.gov, number NCT 01291576. TRIAL REGISTRATION DATE 31 January 2011. DATE OF FIRST PATIENT’S ENROLMENT 7 March 2011. PMID:29194531

Phase I Trial of Universal Donor NK Cell Therapy in Combination With ALT803

ClinicalTrials.gov

2018-01-20

Acute Myeloid Leukemia; Myelodysplastic Syndrome; Acute Lymphoblastic Leukemia; Chronic Myeloid Leukemia; Chronic Lymphocytic Leukemia; Non Hodgkin Lymphoma; Hodgkin Lymphoma; Myeloproliferative Syndromes; Plasma Cell Myeloma; Colon Carcinoma; Adenocarcinoma of Rectum; Soft Tissue Sarcoma; Ewing's Sarcoma; Rhabdomyosarcoma

Multiple myeloma presenting as CEA-producing rectal cancer.

PubMed

Talamo, Giampaolo; Barochia, Amitkumar; Zangari, Maurizio; Loughran, Thomas P

2010-03-31

We report the case of a 57-year-old patient with multiple myeloma, characterized by extramedullary involvement of the rectum at presentation. Malignant plasma cells were found to produce carcinoembryonic antigen (CEA), a tumor antigen more commonly associated with rectal adenocarcinomas.

Gastrointestinal Carcinoid Tumors—Patient Version

Cancer.gov

Gastrointestinal (GI) carcinoid tumors are slow-growing tumors that form in the neuroendocrine cells in the GI tract. The GI tract includes the stomach, small intestine, colon, rectum, appendix, and other organs. Start here to find treatment information and research on gastrointestinal carcinoid tumors.

Proctitis

MedlinePlus

... Your Digestive System & How it Works Zollinger-Ellison Syndrome Proctitis View or Print All Sections Definition & Facts Proctitis is inflammation of the lining of the rectum. Proctitis may be acute or chronic. Anal sex, inflammatory bowel disease, or radiation therapy to your pelvic area or abdomen may ...

How to Prevent Sexually Transmitted Diseases

MedlinePlus

... genitals, mouth, rectum, or body fluids. Anyone who has sexual contact—vaginal, anal, or oral sex—with another ... the risk of getting STIs: • More than one sexual partner • A partner who has or has had more than one sexual partner • ...

First-in-Human Positron Emission Tomography Study Using the 18F-αvβ6-Binding-Peptide

ClinicalTrials.gov

2018-03-01

Breast Carcinoma; Colorectal Carcinoma; Lung Carcinoma; Metastatic Malignant Neoplasm in the Breast; Metastatic Malignant Neoplasm in the Colon; Metastatic Malignant Neoplasm in the Lung; Metastatic Malignant Neoplasm in the Rectum; Pancreatic Carcinoma

Multiple myeloma presenting as CEA-producing rectal cancer

PubMed Central

Talamo, Giampaolo; Barochia, Amitkumar; Zangari, Maurizio; Loughran, Thomas P

2010-01-01

We report the case of a 57-year-old patient with multiple myeloma, characterized by extramedullary involvement of the rectum at presentation. Malignant plasma cells were found to produce carcinoembryonic antigen (CEA), a tumor antigen more commonly associated with rectal adenocarcinomas. PMID:21139949

Dosimetric evaluation of two treatment planning systems for high dose rate brachytherapy applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shwetha, Bondel; Ravikumar, Manickam, E-mail: drravikumarm@gmail.com; Supe, Sanjay S.

2012-04-01

Various treatment planning systems are used to design plans for the treatment of cervical cancer using high-dose-rate brachytherapy. The purpose of this study was to make a dosimetric comparison of the 2 treatment planning systems from Varian medical systems, namely ABACUS and BrachyVision. The dose distribution of Ir-192 source generated with a single dwell position was compared using ABACUS (version 3.1) and BrachyVision (version 6.5) planning systems. Ten patients with intracavitary applications were planned on both systems using orthogonal radiographs. Doses were calculated at the prescription points (point A, right and left) and reference points RU, LU, RM, LM, bladder,more » and rectum. For single dwell position, little difference was observed in the doses to points along the perpendicular bisector. The mean difference between ABACUS and BrachyVision for these points was 1.88%. The mean difference in the dose calculated toward the distal end of the cable by ABACUS and BrachyVision was 3.78%, whereas along the proximal end the difference was 19.82%. For the patient case there was approximately 2% difference between ABACUS and BrachyVision planning for dose to the prescription points. The dose difference for the reference points ranged from 0.4-1.5%. For bladder and rectum, the differences were 5.2% and 13.5%, respectively. The dose difference between the rectum points was statistically significant. There is considerable difference between the dose calculations performed by the 2 treatment planning systems. It is seen that these discrepancies are caused by the differences in the calculation methodology adopted by the 2 systems.« less

Evaluation of atlas-based auto-segmentation software in prostate cancer patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenham, Stuart, E-mail: stuart.greenham@ncahs.health.nsw.gov.au; Dean, Jenna; Fu, Cheuk Kuen Kenneth

2014-09-15

The performance and limitations of an atlas-based auto-segmentation software package (ABAS; Elekta Inc.) was evaluated using male pelvic anatomy as the area of interest. Contours from 10 prostate patients were selected to create atlases in ABAS. The contoured regions of interest were created manually to align with published guidelines and included the prostate, bladder, rectum, femoral heads and external patient contour. Twenty-four clinically treated prostate patients were auto-contoured using a randomised selection of two, four, six, eight or ten atlases. The concordance between the manually drawn and computer-generated contours were evaluated statistically using Pearson's product–moment correlation coefficient (r) and clinicallymore » in a validated qualitative evaluation. In the latter evaluation, six radiation therapists classified the degree of agreement for each structure using seven clinically appropriate categories. The ABAS software generated clinically acceptable contours for the bladder, rectum, femoral heads and external patient contour. For these structures, ABAS-generated volumes were highly correlated with ‘as treated’ volumes, manually drawn; for four atlases, for example, bladder r = 0.988 (P < 0.001), rectum r = 0.739 (P < 0.001) and left femoral head r = 0.560 (P < 0.001). Poorest results were seen for the prostate (r = 0.401, P < 0.05) (four atlases); however this was attributed to the comparison prostate volume being contoured on magnetic resonance imaging (MRI) rather than computed tomography (CT) data. For all structures, increasing the number of atlases did not consistently improve accuracy. ABAS-generated contours are clinically useful for a range of structures in the male pelvis. Clinically appropriate volumes were created, but editing of some contours was inevitably required. The ideal number of atlases to improve generated automatic contours is yet to be determined.« less

The Outlet Patch: Gastric Heterotopia of the Colo-rectum and Anus.

PubMed

Mannan, Abul Ala Syed Rifat; Vieth, Michael; Khararjian, Armen; Khandakar, Binny; Lam-Himlin, Dora; Heydt, David; Bhaijee, Feriyl; Venbrux, Henry J; Byrnes, Kathleen; Voltaggio, Lysandra; Barker, Norman; Yuan, Songyang; Montgomery, Elizabeth

2018-04-18

Gastric heterotopia (GH) has been described throughout the gastrointestinal tract. However, the colorectal region is an extremely rare location for it. We describe the clinicopathologic features of GH of the colon, rectum, and anus. We identified 33 cases in 20 males and 13 females (median age 54 years; range, 4 months to 73 years). Sites included the rectum (N=26), anus (N=4), ileocecal junction (N=1), ascending colon (N=1) and descending colon (N=1). Presenting symptoms(N=27) included hematochezia (41%) and altered bowel habits (4%); 15 patients (55%) were asymptomatic. On colonoscopy (N=31), all appeared as solitary lesions, (median size 6.5 mm, range 2 mm - 55 mm), either as polyps (61%), raised erythematous patches (23%), an ulcer(10%), within a rectal diverticulum (3%), or a hemorrhoid (3%). Patients were managed by polypectomy. One with an associated carcinoma in the area of GH underwent resection. No morbidity related to GH itself was reported following excision. Histologically, heterotopic gastric mucosa was oxyntic type (85%), mixed oxyntic and non-oxyntic type (12%), and not specified (3%). In 5 patients a pyloric gland adenoma (PGA) arose from heterotopic gastric mucosa, two of which contained a focus of invasive adenocarcinoma. One case had associated surface foveolar type low-grade dysplasia. Another had associated adenocarcinoma arising from the heterotopic mucosa. One example harbored Helicobacter pylori organisms. We highlight the features of GH in the distal GIT - the 'outlet patch'. Association with PGA, surface dysplasia and adenocarcinoma suggests that lower tract GH can undergo neoplastic transformation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

A survey of abnormalities in the colon and rectum in patients with haemorrhoids.

PubMed

Koning, Mark V; Loffeld, Ruud J L F

2010-07-07

Haemorrhoids are a common problem in daily practice. However, symptoms may also be caused by other abnormalities in the rectum or colon. Data on the presence of these abnormalities in patients with haemorrhoids is sparse. To examine the prevalence of abnormalities of the colon or rectum in patients with and without haemorrhoids, stratified for age. In a 17-year period 1910 consecutive patients with haemorrhoids and 7936 patients without haemorrhoids were analysed retrospectively. All of these patients had an endoscopic examination for different clinical reasons. All significant endoscopic co-findings (diverticuli, polyps, cancer, angiodysplasia and varices, or colitis) were recorded. The patients were divided in 2 groups. Group 1 (n = 861 (45.1%)) consisted of patients with only haemorrhoids, group 2 (n = 1049 (54.9%)) consisted of patients with haemorrhoids and another endoscopic diagnosis. Patients in group 1 were significantly younger, mean age 55.3 +/- 14.1 years versus 67.4 +/- 12.1 years (p < 0.001), and underwent significantly more often a sigmoidoscopy, 11% versus 2% (p < 0.0001). Furthermore, endoscopic co-findings were found with increasing age. The majority of diverticuli, polyps, cancer and vascular lesions were detected in the age group above 50 years, while only colitis was more often present in the younger group. There was no significant difference in gender when group 1 and 2 were compared with the reference group. Diverticuli and angiodysplasia/varices occurred significantly more often in group 2. The other significant diagnoses were diagnosed more often in the reference group. In patients with haemorrhoids other abnormalities can be present. Especially in older patients the clinician must be cautious to attribute complaints solely to haemorrhoids.

Risk Factors of Anastomotic Leakage and Long-Term Survival After Colorectal Surgery

PubMed Central

Park, Jong Seob; Huh, Jung Wook; Park, Yoon Ah; Cho, Yong Beom; Yun, Seong Hyeon; Kim, Hee Cheol; Lee, Woo Yong

2016-01-01

Abstract Anastomotic leakage (AL) is one of the most serious complications of colorectal surgery. It can affect long-term oncologic outcomes, but the impact on long-term survival remains uncertain. The aim of this study is to evaluate the operative characteristics of leakage and no leakage groups and to analyze long-term oncologic outcomes. We prospectively enrolled 10,477 patients from 2000 to 2011 and retrospectively reviewed the data. Male sex (odds ratio [OR], 3.90; P < 0.001), intraoperative transfusion (OR, 2.31; P = 0.042), and operative time (OR, 1.73; P = 0.032) were independent risk factors of AL in the colon. In the rectum, male sex (OR, 2.37; P < 0.001), neoadjuvant chemoradiotherapy (OR, 2.26; P < 0.001), and regional lymph node metastasis (OR, 1.43; P = 0.012) were independent risk factors of AL, and diverting stoma (OR, 0.24; P < 0.001) was associated with a deceased risk of AL. AL in the rectum without a diverting stoma was associated with disease-free survival (DFS, OR, 1.47; P = 0.037). Colonic leakage was not associated with 5-year DFS (leakage group vs nonleakage group, 72.4% vs 80.9%, P = 0.084); however, in patients undergoing rectal resection, there was a significant difference in 5-year DFS (67.0% vs 76.6%, P = 0.005, respectively). AL in the rectum is associated with worse long-term DFS and overall survival. A diverting stoma was shown to protect against this effect and was associated with long-term survival in rectal surgery. Therefore, creating a diverting stoma should be considered in high-risk patients undergoing rectal surgery. PMID:26937928

Colonization sites in carriers of ESBL-producing Gram-negative bacteria.

PubMed

van Prehn, Joffrey; Kaiser, Anna M; van der Werff, Suzanne D; van Mansfeld, Rosa; Vandenbroucke-Grauls, Christina M J E

2018-01-01

The distribution of Extended-Spectrum Beta-Lactamase-producing Gram-negative bacteria (ESBL-GNB) colonization sites is relevant for infection control guidelines on detection and follow-up of colonization. We questioned whether it is possible to rely solely on rectal swab culture for follow-up of ESBL-GNB colonization. We retrospectively assessed ESBL-GNB colonization sites in patients in a tertiary hospital in the Netherlands. The Laboratory Information Management System was queried for all bacterial cultures obtained between January 2012 and August 2016. All patients with one or more cultures positive for ESBL-GNB were identified and the distribution of ESBL-GNB positive sample sites was assessed. A subgroup analysis was performed on patients for whom at least one rectal swab specimen was available. We identified 1011 ESBL-GNB carriers with 16,578 specimens for analysis. ESBL-GNB were most frequently isolated from the rectum (506/1011), followed by the urogenital (414/1011) and respiratory tract (142/1011), and pus (136/1011). For 588 patients at least one rectal swab specimen was available. In this subgroup, ESBL-GNB colonization was detected only in the rectum in 55.4% (326/588) of patients, in 30.6% (180/588) in the rectum and a different culture site, and in 13.9% (82/588) no rectal colonization was detected. Rectal colonization with ESBL-GNB was detected in 86% of ESBL-GNB carriers. However, in 14% of ESBL-GNB carriers we did not detect rectal colonization. Therefore, samples taken for follow-up of colonization with multi-drug resistant Gram-negative bacteria (MDR-GNB) should ideally also include samples from the site where the MDR-GNB was initially found.

Anorectal Stimulation Causes Increased Colonic Motor Activity in Subjects With Spinal Cord Injury

PubMed Central

Korsten, Mark A; Singal, Ashwani K; Monga, Amit; Chaparala, Geeta; Khan, Amir M; Palmon, Ron; Mendoza, John Reagan D; Lirio, Juan P; Rosman, Alan S; Spungen, Ann; Bauman, William A

2007-01-01

Background: Difficulty with evacuation (DWE) is a major problem after spinal cord injury (SCI). Stimulation of the anal canal and lower rectum, accomplished using a gloved finger (so-called digital rectal stimulation or DRS) is often used as an adjunct to laxatives and enemas to facilitate bowel evacuation. However, the basis for the efficacy of DRS is not known. This study assessed the effect of DRS on colonic motility. Methods: Six subjects with SCI were studied several hours after a bowel care session. Colonic motility was assessed using a manometric catheter (affixed endoscopically to the splenic flexure) at baseline, during DRS, and after DRS. In addition, evacuation of barium oatmeal paste (with the consistency of stool and introduced into the rectum and descending colon) was assessed simultaneously using fluoroscopic techniques. Results: The mean number (± SEM) of peristaltic waves per minute increased from 0 at baseline to 1.9 (±0.5/min) during DRS and 1.5 (±0.3/min) during the period immediately after cessation of DRS (P < 0.05). The mean amplitude (±SEM) of the peristaltic contractions was 43.4 (±2.2) mmHg. The frequency of contractions, as well as amplitude of contractions, during or immediately after DRS was not significantly different. These manometric changes in response to DRS were accompanied by expulsion of barium oatmeal paste in every subject by the fifth DRS. Conclusions: DRS causes left-sided colonic activity in subjects with SCI. At least in part, an anorectal colonic reflex that results in enhanced contractions of the descending colon and rectum may contribute to bowel evacuation in individuals with SCI. PMID:17385267

Thermoluminescence dosimetry for in-vivo verification of high dose rate brachytherapy for prostate cancer.

PubMed

Das, R; Toye, W; Kron, T; Williams, S; Duchesne, G

2007-09-01

It was the aim of the study to verify dose delivered in urethra and rectum during High Dose Rate brachytherapy boost (HDRBB) of prostate cancer patients. During the first fraction of HDRBB measurement catheters were placed in the urethra and rectum of prostate cancer patients. These contained LiF:Mg,Ti Thermoluminescence Dosimetry (TLD) rods of 1 mm diameter, with up to 11 detectors positioned every 16 mm separated by radio-opaque markers. A Lorentzian peak function was used to fit the data. Measurements from 50 patients were evaluated and measured doses were compared with predictions from the treatment planning system (Plato Vs 13.5 to 14.1). Prospective urinary and rectal toxicity scores were collected following treatment. In more than 90% of cases, the Lorentzian peak function provided a good fit to both experimental and planning urethral data (r2 > 0.9). In general there was good agreement between measured and predicted doses with the average difference between measured and planned maximum dose being 0.1 Gy. No significant association between dose and any clinical endpoints was observed in 43 patients available for clinical evaluation. An average inferior shift of 2 mm between the plan and the measurement performed approximately 1 hour after the planning CT scan was found for the dose distribution in the cohort of patients for the urethra measurements. Rectal measurements proved to be more difficult to interpret as there is more variability of TLD position between planning and treatment. TLD in-vivo measurements are easily performed in urethra and rectum during HDR brachytherapy of prostate patients. They verify the delivery and provide information about the dose delivered to critical structures. The latter may be of particular interest if higher doses are to be given per fraction such as in HDR monotherapy.

Shedding of Hepatitis C Virus Into the Rectum of HIV-infected Men Who Have Sex With Men.

PubMed

Foster, Andrew L; Gaisa, Michael M; Hijdra, Rosanne M; Turner, Samuel S; Morey, Tristan J; Jacobson, Karen B; Fierer, Daniel S

2017-02-01

For over a decade we have known of an epidemic of sexually transmitted hepatitis C virus (HCV) infection among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM), but there still remains significant controversy over which bodily fluid(s) are responsible for HCV transmission in these men. We enrolled HIV-infected MSM with recent and chronic HCV infection and quantified HCV from rectal fluid obtained by blind swab. We compared the rectal HCV viral load (VL) with paired blood HCV VL. We found rectal HCV shedding in 20 (47%) of 43 men, only one (2%) of whom had visible bleeding. Detection of rectal HCV shedding was associated with blood VL > 5 log 10 IU/mL (p = .01), and 85% with blood VL > 5 log 10 IU/mL had rectal shedding. The HCV VL of the rectal fluid ranged from 2.6 to 5.5 log 10 IU/mL. Based on the median rectal fluid VL, the surface of an average human penis would be exposed to at least 2,300 IU of HCV for the duration of anal intercourse. This study provides the first direct evidence to our knowledge that a sufficient quantity of HCV is shed into the rectum in HIV-infected men with HCV infection to directly infect an inserted penis or be passed indirectly through fomite-like transmission to the rectum of sex partner. We must develop an appropriate public health campaign to educate MSM about these routes of HCV infection to reverse the HCV epidemic among HIV-infected MSM. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Improvement of digestive complaints in women with severe colorectal endometriosis benefiting from continuous amenorrhoea triggered by triptorelin. A prospective pilot study.

PubMed

Roman, H; Saint Ghislain, M; Milles, M; Marty, N; Hennetier, C; Moatassim, S; Desnyder, E; Abo, C

2015-09-01

To assess the impact of therapeutic amenorrhoea triggered by triptorelin in the digestive complaints of women with deep endometriosis infiltrating the rectum. Prospective series of consecutive patients with deep endometriosis of the rectum enrolled over a period of 17 consecutive months. University tertiary referral center. Seventy patients. Medical therapy (triptorelin 11.25 mg and add-back therapy using estradiol) administered for 3.4±1.8months before surgery. Gastrointestinal standardised questionnaires before beginning medical treatment and the day before surgery. The most frequent digestive complaints at baseline were: defecation pain in 77.1% of patients, bloating in 60%, diarrhoea in 54.3% and constipation in 50%. The largest diameter of the rectal area infiltrated by the disease was <1cm in 12.2% of women, 1 to 2.9 cm in 34.3% and ≥3cm in 51.4%. Multiple colorectal nodules were found in 32.9%. Medical treatment led to disappearance of cyclic defecation pain in 78.6%, dyschesia in 58.3%, diarrhoea in 58.3% and bloating in 50%. Relieving digestive complaints was not significantly related to either length of triptorelin administration or size of rectal infiltration by deep endometriosis. Therapeutic amenorrhoea averaging 3 months allowed complete improvement of various cyclic digestive complaints in more than half of patients. In selected patients, continuous therapeutic amenorrhoea could compensate for the lack of complete resection of deep infiltrating endometriosis of the rectum, when this latter is likely to result in a high rate of postoperative morbidity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Does the primary site of colorectal cancer impact outcomes for patients with metastatic disease?

PubMed

Price, Timothy J; Beeke, Carol; Ullah, Shahid; Padbury, Robert; Maddern, Guy; Roder, David; Townsend, Amanda R; Moore, James; Roy, Amitesh; Tomita, Yoko; Karapetis, Christos

2015-03-15

Previous reports have described differences in biology and outcome for colorectal cancer based on whether the primary is right or left sided. Further division by right, left, and rectum or even exact primary site has also been explored. Possible differences in response to biological agents have also been reported based on side of primary lesion. We explored the South Australian registry for metastatic colorectal cancer to assess if there were any differences in patient characteristics, prognostic markers, and treatment received and outcomes based on whether the primary was right or left sided. We also explored if differences exist based on left colon and rectum and by exact primary site. Two thousand nine hundred seventy-two patients were analyzed. Thirty-five percent had a right-sided primary. The median overall survival for the entire group right versus left was 9.6 versus 20.3 months (P < .001). Multivariate analysis confirmed side of primary as an independent prognostic factor. For the group that had active therapy, defined as chemotherapy (± metastasis resection), median overall survival was right, 18.2 months; and left, 29.4 months (P < .001). Importantly, we found no suggestion of major differences if left side was divided by left colon and rectum, and trends by individual site still supported a left and right division. Patients with a right-sided primary have more negative prognostic factors and indeed have inferior outcomes compared with those with a left-sided primary. Our data with further breakdown by exact site still favor a simple left-versus-right division moving forward for metastatic colorectal cancer. © 2014 American Cancer Society.

The prevalence of lymphogranuloma venereum infection in men who have sex with men: results of a multicentre case finding study

PubMed Central

Ward, H; Alexander, S; Carder, C; Dean, G; French, P; Ivens, D; Ling, C; Paul, J; Tong, W; White, J; Ison, C A

2009-01-01

Objective: To determine the prevalence of lymphogranuloma venereum (LGV) and non-LGV associated serovars of urethral and rectal Chlamydia trachomatis (CT) infection in men who have sex with men (MSM). Design: Multicentre cross-sectional survey. Setting: Four genitourinary medicine clinics in the United Kingdom from 2006–7. Subjects: 4825 urethral and 6778 rectal samples from consecutive MSM attending for sexual health screening. Methods: Urethral swabs or urine and rectal swabs were tested for CT using standard nucleic acid amplification tests. Chlamydia-positive specimens were sent to the reference laboratory for serovar determination. Main outcome: Positivity for both LGV and non-LGV associated CT serovars; proportion of cases that were symptomatic. Results: The positivity (with 95% confidence intervals) in rectal samples was 6.06% (5.51% to 6.66%) for non-LGV CT and 0.90% (0.69% to 1.16%) for LGV; for urethral samples 3.21% (2.74% to 3.76%) for non-LGV CT and 0.04% (0.01% to 0.16%) for LGV. The majority of LGV was symptomatic (95% of rectal, one of two urethral cases); non-LGV chlamydia was mostly symptomatic in the urethra (68%) but not in the rectum (16%). Conclusions: Chlamydial infections are common in MSM attending for sexual health screening, and the majority are non-LGV associated serovars. We did not identify a large reservoir of asymptomatic LGV in the rectum or urethra. Testing for chlamydia from the rectum and urethra should be included for MSM requesting a sexual health screen, but serovar-typing is not indicated in the absence of symptoms. We have yet to identify the source of most cases of LGV in the UK. PMID:19221105

The effect of tandem-ovoid titanium applicator on points A, B, bladder, and rectum doses in gynecological brachytherapy using 192Ir

PubMed Central

Sadeghi, Mohammad Hosein; Mehdizadeh, Amir; Faghihi, Reza; Moharramzadeh, Vahed; Meigooni, Ali Soleimani

2018-01-01

Purpose The dosimetry procedure by simple superposition accounts only for the self-shielding of the source and does not take into account the attenuation of photons by the applicators. The purpose of this investigation is an estimation of the effects of the tandem and ovoid applicator on dose distribution inside the phantom by MCNP5 Monte Carlo simulations. Material and methods In this study, the superposition method is used for obtaining the dose distribution in the phantom without using the applicator for a typical gynecological brachytherapy (superposition-1). Then, the sources are simulated inside the tandem and ovoid applicator to identify the effect of applicator attenuation (superposition-2), and the dose at points A, B, bladder, and rectum were compared with the results of superposition. The exact dwell positions, times of the source, and positions of the dosimetry points were determined in images of a patient and treatment data of an adult woman patient from a cancer center. The MCNP5 Monte Carlo (MC) code was used for simulation of the phantoms, applicators, and the sources. Results The results of this study showed no significant differences between the results of superposition method and the MC simulations for different dosimetry points. The difference in all important dosimetry points was found to be less than 5%. Conclusions According to the results, applicator attenuation has no significant effect on the calculated points dose, the superposition method, adding the dose of each source obtained by the MC simulation, can estimate the dose to points A, B, bladder, and rectum with good accuracy. PMID:29619061

Thallium-201 per rectum for the diagnosis of cirrhosis in patients with asymptomatic chronic hepatitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

D'Arienzo, A.; Celentano, L.; Scuotto, A.

1988-07-01

In normal subjects, thallium-201, administered per rectum, is taken up mainly by the liver (heart/liver ratio in normal subjects: 0.04 to 0.12). It has been claimed that an increased heart/liver ratio is suggestive of portal-caval shunting and portal hypertension. To evaluate the possibility of using thallium-201 as a test to diagnose cirrhosis, we administered this substance per rectum to 33 patients with biochemical evidence, but no clinical symptoms, of liver disease. Laparoscopy and liver biopsy revealed chronic active hepatitis without cirrhosis in 18 patients, and chronic active hepatitis with cirrhosis in the others. The results of conventional liver function testsmore » were similar in both groups. A significant difference, however, was found between the means of fasting serum bile acid concentrations (9.8 +/- 3.2 and 18.3 +/- 4.2 microM per liter) in chronic active hepatitis without cirrhosis and cirrhotic patients, and between the means of the heart/liver ratios 20 min after thallium-201 administration (heart/liver: 0.09 +/- 0.03 and 0.54 +/- 0.13, respectively). Unlike the serum bile acid concentration which gave some overlapping values, the thallium-201 test clearly distinguished the chronic active hepatitis without cirrhosis group from the cirrhotics. In the cirrhotic group, there was a significant correlation between the heart/liver ratio and signs of portal hypertension such as esophageal varices, increased diameter of the vena porta and hypersplenism. The thallium-201 test is therefore useful in discriminating between chronic active hepatitis with and without cirrhosis in clinically asymptomatic subjects with biochemical evidence of moderate liver function impairment. A heart/liver uptake ratio much higher than normal (above 0.30) strongly suggests the development of hepatic cirrhosis.« less

Poster — Thur Eve — 13: Inter-Fraction Target Movement in Image-Guided Radiation Therapy of Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Congwu; Zeng, Grace G.; Department of Radiation Oncology, University of Toronto, Toronto, ON

2014-08-15

We investigated the setup variations over the treatment courses of 113 patients with intact prostate treated with 78Gy/39fx. Institutional standard bladder and bowel preparation and image guidance protocols were used in CT simulation and treatment. The RapidArc treatment plans were optimized in Varian Eclipse treatment planning system and delivered on Varian 2100X Clinacs equipped with On-Board Imager to localize the target before beam-on. The setup variations were calculated in terms of mean and standard deviation of couch shifts. No correlation was observed between the mean shift and standard deviation over the treatment course and patient age, initial prostate volume andmore » rectum size. The mean shifts in the first and last 5 fractions are highly correlated (P < 10{sup −10}) while the correlation of the standard deviations cannot be determined. The Mann-Kendall tests indicate trends of the mean daily Ant-Post and Sup-Inf shifts of the group. The target is inferior by ∼1mm to the planned position when the treatment starts and moves superiorly, approaching the planned position at 10th fraction, and then gradually moves back inferiorly by ∼1mm in the remain fractions. In the Ant-Post direction, the prostate gradually moves posteriorly during the treatment course from a mean shift of ∼2.5mm in the first fraction to ∼1mm in the last fraction. It may be related to a systematic rectum size change in the progress of treatment. The biased mean shifts in Ant-Post and Sup-Inf direction of most patients suggest systematically larger rectum and smaller bladder during the treatment than at CT simulation.« less

Correlations between contouring similarity metrics and simulated treatment outcome for prostate radiotherapy

NASA Astrophysics Data System (ADS)

Roach, D.; Jameson, M. G.; Dowling, J. A.; Ebert, M. A.; Greer, P. B.; Kennedy, A. M.; Watt, S.; Holloway, L. C.

2018-02-01

Many similarity metrics exist for inter-observer contouring variation studies, however no correlation between metric choice and prostate cancer radiotherapy dosimetry has been explored. These correlations were investigated in this study. Two separate trials were undertaken, the first a thirty-five patient cohort with three observers, the second a five patient dataset with ten observers. Clinical and planning target volumes (CTV and PTV), rectum, and bladder were independently contoured by all observers in each trial. Structures were contoured on T2-weighted MRI and transferred onto CT following rigid registration for treatment planning in the first trial. Structures were contoured directly on CT in the second trial. STAPLE and majority voting volumes were generated as reference gold standard volumes for each structure for the two trials respectively. VMAT treatment plans (78 Gy to PTV) were simulated for observer and gold standard volumes, and dosimetry assessed using multiple radiobiological metrics. Correlations between contouring similarity metrics and dosimetry were calculated using Spearman’s rank correlation coefficient. No correlations were observed between contouring similarity metrics and dosimetry for CTV within either trial. Volume similarity correlated most strongly with radiobiological metrics for PTV in both trials, including TCPPoisson (ρ  =  0.57, 0.65), TCPLogit (ρ  =  0.39, 0.62), and EUD (ρ  =  0.43, 0.61) for each respective trial. Rectum and bladder metric correlations displayed no consistency for the two trials. PTV volume similarity was found to significantly correlate with rectum normal tissue complication probability (ρ  =  0.33, 0.48). Minimal to no correlations with dosimetry were observed for overlap or boundary contouring metrics. Future inter-observer contouring variation studies for prostate cancer should incorporate volume similarity to provide additional insights into dosimetry during analysis.

Common dietary patterns and risk of cancers of the colon and rectum: Analysis from the United Kingdom Women's Cohort Study (UKWCS).

PubMed

Rada-Fernandez de Jauregui, Diego; Evans, Charlotte E L; Jones, Petra; Greenwood, Darren C; Hancock, Neil; Cade, Janet E

2018-03-08

Few prospective cohort studies in the UK have specifically focused on the associations between commonly consumed dietary patterns and colorectal cancer (CRC). The aim of our study was to assess whether red meat, poultry, fish and vegetarian dietary patterns are associated with differences in the incidence of cancers of colon and rectum in the UKWCS. Four common dietary patterns were defined based on a hierarchy of consumption of red meat, poultry and fish for each cohort participant, using a 217-item food frequency questionnaire. Cox proportional hazards regression was used to provide adjusted hazard ratios (HR) and 95% confidence intervals (CI) for CRC. A total of 32,147 women recruited and surveyed between 1995 and 1998 were followed up for a mean of 17.2 years (426,798 person-years). A total of 462 incident CRC cases were documented; 335 colon cancers (172 proximal and 119 distal) and 152 in the rectum. In multivariable-adjusted models, there was no evidence of a reduction in risk of overall CRC (HR = 0.86, 95% CI: 0.66-1.12), colon cancer (HR = 0.77, 95% CI: 0.56-1.05) or rectal cancer (HR = 1.04, 95% CI: 0.66-1.63) when comparing grouped red meat free diets with diets containing red meat. Exploratory analysis suggested a reduced risk of distal colon cancer in grouped red meat free diets (HR = 0.56, 95% CI: 0.34-0.95), though numbers with this outcome were small. These results indicate that a protective association of red meat free diets specifically on distal colon cancer merits confirmation in a larger study. © 2018 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

Squamous cell dysplasia in the proximal rectum of three patients treated for ulcerative colitis on immunomodulators.

PubMed

Connolly, James G; Goldstone, Stephen E

2017-05-01

Anal canal high-grade squamous intraepithelial lesion (HSIL) is the precursor to anal cancer. Immunocompromised patients are at increased risk and disease is usually within 3 cm from the anal verge. High-resolution anoscopy (HRA) with an 8-cm anoscope is used to identify and guide cautery treatment of HSIL. We report three patients with a long-term history of ulcerative colitis (UC) treated with systemic immunomodulators who developed proximally located rectal HSIL. Two patients were HIV-negative women, 63 and 48 years old, and the third was a 51-year-old HIV-positive man with underlying UC for 10, 16, and 3 years, respectively. They each presented with a HPV-positive HSIL visibly extending above the limits of the anoscope used for HRA. None developed cancer. All had episodes of active UC. It is unclear what causative role systemic immunomodulators play in predisposing UC patients to proximal HSIL. HSIL probably developed on a tongue of HPV-infected squamous epithelium growing proximally over the inflamed rectum. Islands developed when areas of squamous epithelium degenerated, creating skip areas. This study highlights the potential for HSIL to extend into the rectum either as a contiguous patch or isolated islands and the need for heightened surveillance in patients with extensive anal canal HSIL treated with immunodulator therapy. HSIL identified at the limit of the anoscope should be investigated further with colonoscopy, and argon plasma coagulation (APC) ablation can serve as an effective treatment option. Patients are at risk for stricture, but it is unclear what role the UC or the ablation played in stricture formation.

Increased bioavailability of propranolol in rats by retaining thermally gelling liquid suppositories in the rectum.

PubMed

Ryu, J M; Chung, S J; Lee, M H; Kim, C K; ShimCK

1999-05-20

Mucoadhesive liquid suppositories were prepared by adding mucoadhesive polymers (0.6%) to a formulation of thermally gelling suppositories that contained poloxamer 407 (15%), poloxamer 188 (15%) and propranolol HCl (2%). Hydroxypropylcellulose (HPC), polyvinylpyrrolidone (PVP), carbopol, polycarbophil and sodium alginate were examined as mucoadhesive polymers. The characteristics of the suppositories differed depending on the choice of mucoadhesive polymer. For example, the gelation temperature was between 30 and 36 degrees C, the mucoadhesive force was between 430 and 5800 dyne/cm2, the apparent first-order release rate constant in phosphate buffer, pH 6.8, was between 0.399 and 0.271 h-1, the migration distance of the suppository in the rectum 4 h after administration was between 1 and 5 cm, and the bioavailability of propranolol was between 60.9 and 84.7%. Rectal bioavailability increased as the mucoadhesive force increased (r=0.984, p<0.0005), and the migration distance decreased (r=-0.951, p<0.005). No relationship was found between the bioavailability and the gelation temperature, drug release or irritation of the rectal mucosal membrane by the suppository. Therefore, retaining propranolol at the dosed site in the rectum by the addition of appropriate mucoadhesives to the formulation of liquid suppositories appears to be a very important factor in avoiding first-pass hepatic elimination and thereby increasing the bioavailability of the drug. Among the mucoadhesive polymers examined, sodium alginate and polycarbophil exhibited the largest mucoadhesive force and the smallest intrarectal migration resulting in the largest bioavailability of propranolol (84.7 and 82.3%, respectively). In contrast to other polymers, sodium alginate alone caused no irritation of the rectal mucosal membrane. Thus, poloxamer liquid suppositories containing sodium alginate appears to be a preferred formulation for drugs that are sensitive to extensive first-pass metabolism.

In Vivo Dosimetry of High-Dose-Rate Interstitial Brachytherapy in the Pelvic Region: Use of a Radiophotoluminescence Glass Dosimeter for Measurement of 1004 Points in 66 Patients With Pelvic Malignancy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nose, Takayuki; Department of Physics, Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo; Koizumi, Masahiko

2008-02-01

Purpose: To perform the largest in vivo dosimetry study for interstitial brachytherapy yet to be undertaken using a new radiophotoluminescence glass dosimeter (RPLGD) in patients with pelvic malignancy and to study the limits of contemporary planning software based on the results. Patients and Methods: Sixty-six patients with pelvic malignancy were treated with high-dose-rate interstitial brachytherapy, including prostate (n = 26), gynecological (n = 35), and miscellaneous (n = 5). Doses for a total of 1004 points were measured by RPLGDs and calculated with planning software in the following locations: rectum (n = 549), urethra (n = 415), vagina (n =more » 25), and perineum (n = 15). Compatibility (measured dose/calculated dose) was analyzed according to dosimeter location. Results: The compatibility for all dosimeters was 0.98 {+-} 0.23, stratified by location: rectum, 0.99 {+-} 0.20; urethra, 0.96 {+-} 0.26; vagina, 0.91 {+-} 0.08; and perineum, 1.25 {+-} 0.32. Conclusions: Deviations between measured and calculated doses for the rectum and urethra were greater than 20%, which is attributable to the independent movements of these organs and the applicators. Missing corrections for inhomogeneity are responsible for the 9% negative shift near the vaginal cylinder (specific gravity = 1.24), whereas neglect of transit dose contributes to the 25% positive shift in the perineal dose. Dose deviation of >20% for nontarget organs should be taken into account in the planning process. Further development of planning software and a real-time dosimetry system are necessary to use the current findings and to achieve adaptive dose delivery.« less

Differential Penetration of Raltegravir throughout Gastrointestinal Tissue: Implications for Eradication and Cure

PubMed Central

Patterson, Kristine B.; Prince, Heather A.; Stevens, Trenton; Shaheen, Nicholas J.; Dellon, Evan S.; Madanick, Ryan D.; Jennings, Steven; Cohen, Myron S.; Kashuba, Angela D.M.

2014-01-01

Objective To investigate the concentration of the integrase strand inhibitor raltegravir (RAL) throughout gastrointestinal (GI) tissue, especially gutassociated lymphoid tissue (GALT), as an adjunct to current prevention and cure strategies. Design Open-label pharmacokinetic study Methods HIV-negative men received RAL 400 mg twice daily for 7 days. Seven blood plasma (BP) specimens were collected over 12-hr intervals; timed tissue specimens from terminal ileum, splenic flexure, and rectum were also obtained by colonoscopy following the first dose (FD) and on Day 7 [Multiple Dose (MD)]. RAL concentrations were measured by validated LC-MS assay with 1 ng/mL lower limit of detection. Data were analyzed by noncompartmental methods (WinNonlin 6). Tissue exposures are reported as composite medians and tissue density of 1.04 g/mL is assumed for comparisons. Results Fourteen men completed evaluations. Median (range) age was 24 (19–49) yrs and BMI 25 (19–31) kg/m2. After the FD, AUC-0-12h was highest in the terminal ileum (594 μg*h/mL). Exposures were 160, 68 and 39-fold greater than BP at the terminal ileum, splenic flexure and rectum, respectively. After multiple doses, exposure was highest at the splenic flexure (2240 μg*h/mL); exposure at the terminal ileum and rectum were equivalent (both 788 μg*h/mL). Following multiple doses, exposures were 160–650-fold greater than BP throughout the colon. Conclusions RAL rapidly disseminates into GI tissue and concentrations remain significantly higher than BP. RAL exposure in GI tissue remains higher than any ARV investigated to date. These data suggest that RAL should result in full suppression of viral replication in GI tissue and GALT. PMID:23945503

DRINKING WATER AND CANCER INCIDENCE IN IOWA. 2. RADIOACTIVITY IN DRINKING WATER

EPA Science Inventory

This paper presents a logical epidemiologic exploration into possible associations between exposures to radium-226 in drinking water and incidence rates for cancers of the bladder, breast, colon, lung, prostate, and rectum. The most striking finding is the increasing gradient of ...

21 CFR 522.1081 - Chorionic gonadotropin.

Code of Federal Regulations, 2012 CFR

2012-04-01

... if the animal's behavior or examination of the ovaries per rectum indicates retreatment. (A) 10,000... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1081...

Alcohol and Cancer Risk

MedlinePlus

... ounces of malt liquor 5 ounces of wine 1.5 ounces or a "shot" of 80-proof liquor The federal government’s Dietary ... rectum . A meta-analysis of 57 cohort and case-control studies that ... 3.5 drinks) had 1.5 times the risk of developing colorectal cancer ...

[3.0 T MRI with a high resolution protocol for the study of benign disease of the anus and rectum. Part one: High resolution protocol for 3.0 T MRI, anatomic review, benign tumors, and congenital or acquired alterations of the sphincter complex].

PubMed

Herráiz Hidalgo, L; Cano Alonso, R; Carrascoso Arranz, J; Álvarez Moreno, E; Martínez de Vega Fernández, V

2014-01-01

Benign anorectal disease comprises a broad group of processes with very diverse origins; these processes may be congenital or acquired as well as inflammatory or tumor related. However, benign anorectal disease has received less attention in the scientific literature than malignant disease. We present an image-based review of the most common benign diseases of the anus and rectum. In this first part, we review the anatomy of the region and provide a brief description of the peculiarities of the high resolution protocol that we use with 3.0 T MRI. We go on to describe the most common benign anorectal tumors and developmental cystic lesions, together with their differential diagnoses, as well as congenital and acquired anomalies of the anorectal sphincter complex. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

Expression of monocarboxylate transporter 1 (MCT1) in the dog intestine.

PubMed

Shimoyama, Yumiko; Kirat, Doaa; Akihara, Yuko; Kawasako, Kazufumi; Komine, Misa; Hirayama, Kazuko; Matsuda, Kazuya; Okamoto, Minoru; Iwano, Hidetomo; Kato, Seiyu; Taniyama, Hiroyuki

2007-06-01

In this study, the expression and distribution of monocarboxyolate transporter 1 (MCT1) along the intestines (duodenum, jejunum, ileum, cecum, colon and rectum) of dogs were investigated at both the mRNA and protein levels. The expression of MCT1 protein and its distribution were confirmed by Western blotting and immunohistochemical staining using the antibody for MCT1. We identified mRNA coding for MCT1 and a 43-kDa band of MCT1 protein in all regions from the duodenum to the rectum. Immunoreactive staining for MCT1 was also observed in epithelial cells throughout the intestines. MCT1 immunoreactivity was greater in the large intestine than in the small intestine. MCT1 protein was predominantly expressed on the basolateral membranes along intestinal epithelial cells, suggesting that MCT1 may play an important role in lactate efflux and transport of short-chain fatty acids (SCFAs) to the bloodstream across the basolateral membranes of the dog intestine.

Typhoid ulcer causing life-threatening bleeding from Dieulafoy's lesion of the ileum in a seven-year-old child: a case report

PubMed Central

2010-01-01

Introduction We describe a case of rare complication of typhoid fever in a seven-year-old child and review the literature with regard to other rare causes of bleeding per rectum. Dieulafoy's lesion is an uncommon but important cause of recurrent gastrointestinal bleeding. Dieulafoy's lesion located extragastrically is rare. We report a case of typhoid ulcer with Dieulafoy's lesion of the ileum causing severe life-threatening bleeding and discuss the management of this extremely uncommon entity. Case presentation As a complication of typhoid fever, a seven-year-old Kurdish girl from Northern Iraq developed massive fresh bleeding per rectum. During colonoscopy and laparotomy, she was discovered to have multiple bleeding ulcers within the Dieulafoy's lesion in the terminal ileum and ileocecal region. Conclusion Although there is no practical way of predicting the occurrence of such rare complications, we emphasize in this case report the wide array of pathologies that can result from typhoid fever. PMID:20525295

Typhoid ulcer causing life-threatening bleeding from Dieulafoy's lesion of the ileum in a seven-year-old child: a case report.

PubMed

Ezzat, Rajan Fuad; Hussein, Hiwa A; Baban, Trifa Shawkat; Rashid, Abbas Tahir; Abdullah, Khaled Musttafa

2010-06-03

We describe a case of rare complication of typhoid fever in a seven-year-old child and review the literature with regard to other rare causes of bleeding per rectum. Dieulafoy's lesion is an uncommon but important cause of recurrent gastrointestinal bleeding. Dieulafoy's lesion located extragastrically is rare. We report a case of typhoid ulcer with Dieulafoy's lesion of the ileum causing severe life-threatening bleeding and discuss the management of this extremely uncommon entity. As a complication of typhoid fever, a seven-year-old Kurdish girl from Northern Iraq developed massive fresh bleeding per rectum. During colonoscopy and laparotomy, she was discovered to have multiple bleeding ulcers within the Dieulafoy's lesion in the terminal ileum and ileocecal region. Although there is no practical way of predicting the occurrence of such rare complications, we emphasize in this case report the wide array of pathologies that can result from typhoid fever.

A novel in-situ-gelling liquid suppository for site-targeting delivery of anti-colorectal cancer drugs.

PubMed

Lin, Hong-Ru; Tseng, Chao-Chih; Lin, Yiu-Jiuan; Ling, Ming-Hung

2012-01-01

In order to avoid anti-cancer drugs undergoing a first-pass effect and reduce their toxicity, and to solve conventional suppositories defects, we developed an in-situ-gelling and injectable Pluronic-poly(acrylic acid) (Pluronic-PAA) liquid suppository, which could gel fast in the physiological state and had suitable gel strength and bioadhesive force. The liquid suppositories were inserted into the rectum of rabbits without difficulty and leakage, and retained in the rectum for at least 6 h and while releasing the drug. The toxicity and cytotoxic tests indicated that Pluronic and PAA were non-toxic materials and could inhibit colon cancer cells when oxaliplatin was incorporated. C max and AUC0→12h values of oxaliplatin after rectal administration of a oxaliplatin suppository were higher than those for an oxaliplatin solution administered orally. These results suggest that an in-situ-gelling and injectable liquid suppository for humans can be further developed as a more convenient and effective rectal dosage form.

[Small-cell anaplastic neuroendocrine carcinoma of the rectum].

PubMed

Molas, G; Bougis-de-Brux, M A; Potet, F

1987-12-01

A pediculed tumor of the rectum was discovered in a 63 years old man. Within the tumor adenomatous dysplastic proliferation was associated with a neuroendocrine small-cell anaplastic carcinoma. The neuroendocrine nature of the tumor was suspected on conventional optic microscopy and confirmed by a positive Grimelius technique. Specific typical granules were also found on electron microscopy. Immunohistochemical techniques using neurospecific enolase were also positive. Carcinomatous invasion was limited to the submucosa, but the surgical specimen showed that one lymph node was metastatic. Three months later, hepatic metastasis was suspected on physical examination and the patient died of hepatic failure ten months after the discovery of the tumor. Twenty-two similar cases were found in the literature: of these five cases were associated with benign adenomatous lesions. In all cases the patients died of early metastatic diffusion. This tumor raises the problems of diagnosis, terminology, classification and therapy: only aggressive chemotherapy, similar to that applied to the same type of carcinoma in the respiratory tract might improve prognosis.

Different surgical strategies in the treatment of familial adenomatous polyposis: what's the role of the ileorectal anastomosis?

PubMed

Wolthuis, Albert M; Leonard, Daniel; Kartheuser, Alex; Bruyninx, Luc; Van De Stadt, Jean; Van Cutsem, Eric; D'Hoore, André

2011-09-01

Prophylactic (procto-) colectomy is the treatment of choice to reduce the risk of colorectal cancer in FAP patients with multiple adenomas. Because patients present at young age, rectum-sparing surgery is sometimes advocated, so that there is no pelvic dissection with impact on quality of life, preserved pelvic innervation and sexual function and fertility. The main disadvantage of a total colectomy with an ileorectal anastomosis (IRA) is a rectal cancer risk of 50% at the age of 50 years and a cumulative risk of 25.8% after 25 years of follow-up. Therefore, this procedure should be reserved for patients with an unaffected rectum. There should be no discussion to perform a primary IPAA in patients with multiple rectal adenomas (> 20) or those with a severe dysplastic or large (> 3 cm) rectal adenoma or a cancer elsewhere in the colon. A patient with an IRA should undergo yearly follow-up by rectoscopy.

A geometric model for evaluating the effects of inter-fraction rectal motion during prostate radiotherapy

NASA Astrophysics Data System (ADS)

Pavel-Mititean, Luciana M.; Rowbottom, Carl G.; Hector, Charlotte L.; Partridge, Mike; Bortfeld, Thomas; Schlegel, Wolfgang

2004-06-01

A geometric model is presented which allows calculation of the dosimetric consequences of rectal motion in prostate radiotherapy. Variations in the position of the rectum are measured by repeat CT scanning during the courses of treatment of five patients. Dose distributions are calculated by applying the same conformal treatment plan to each imaged fraction and rectal dose-surface histograms produced. The 2D model allows isotropic expansion and contraction in the plane of each CT slice. By summing the dose to specific volume elements tracked by the model, composite dose distributions are produced that explicitly include measured inter-fraction motion for each patient. These are then used to estimate effective dose-surface histograms (DSHs) for the entire treatment. Results are presented showing the magnitudes of the measured target and rectal motion and showing the effects of this motion on the integral dose to the rectum. The possibility of using such information to calculate normal tissue complication probabilities (NTCP) is demonstrated and discussed.

Ischemic Colitis

PubMed Central

Montessori, Gino; Liepa, Egils V.

1970-01-01

Twenty cases of ischemic colitis are reviewed; 19 were obtained from autopsy files and the diagnosis in one was made from a surgical specimen. The majority of the patients were elderly with generalized arteriosclerosis. In approximately two-thirds of the patients the ischemic colitis was precipitated by preceding trauma, operation or congestive heart failure. Clinically, ischemic colitis is characterized by abdominal pain, distension and bleeding per rectum. Perforation of large bowel may occur. The lesions tend to be localized around the splenic flexure and junction of the descending and sigmoid colon, and in cases following aortic graft surgery the rectum is involved. Microscopically, there is necrosis, hemorrhage and ulceration. In less severe cases the mucosa only is affected. Cases with perforation show necrosis of all layers. It is considered that ischemic colitis is comparatively frequent and should be distinguished from other inflammatory conditions of the colon. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5FIG. 6FIG. 7FIG. 8FIG. 9 PMID:5308923

Masculinity and the Body: How African-American and White Men Experience Cancer Screening Exams Involving the Rectum

PubMed Central

Winterich, Julie A.; Quandt, Sara A; Grzywacz, Joseph G.; Clark, Peter E.; Miller, David P.; Acuña, Joshua; Arcury, Thomas A.

2008-01-01

Past research on prostate and colorectal cancer disparities finds that barriers to screening, such as embarrassment and offensiveness, are often reported. Yet none of this literature investigates why. This study uses masculinity and health theory to examine how men experience two common screenings, digital rectal exams (DREs) and colonoscopies. In-depth interviews were conducted with 64 African-American and white men from diverse backgrounds, aged 40–64, from North Carolina, USA. Regardless of race or education, men experienced DREs more negatively than colonoscopies because penetration with a finger was associated with a gay sexual act. Some men disliked colonoscopies, however, because they associated any penetration as an affront to their masculinity. Because beliefs did not differ by race, future research should focus on structural issues to examine why disparities persist with prostate and colorectal cancer. Recommendations are provided for educational programs and physicians to improve men’s experiences with exams that involve the rectum. PMID:19477742

Cancer mortality among Brazilian dentists.

PubMed

Koifman, Sergio; Malhão, Thainá Alves; Pinto de Oliveira, Gisele; de Magalhães Câmara, Volney; Koifman, Rosalina Jorge; Meyer, Armando

2014-11-01

Previous studies have variably shown excess risks of elected cancers among dentists. National Brazilian mortality data were used to obtain mortality patterns among dentists between 1996 and 2004. Cancer mortality odds ratios (MORs) and cancer proportional mortality ratios for all cancer sites were calculated, using the general population and physicians and lawyers as comparison groups. Female dentists from both age strata showed higher risks for breast, colon-rectum, lung, brain, and non-Hodgkin lymphoma. Compared to physicians and lawyers, higher MOR estimates were observed for brain cancer among female dentists 20-49 yr. Among male dentists, higher cancer mortality was found for colon-rectum, pancreas, lung, melanoma, and non-Hodgkin lymphoma. Higher risk estimates for liver, prostate, bladder, brain, multiple myeloma and leukemia were observed among 50-79 yr old male dentists. If confirmed, these results indicate the need for limiting occupational exposures among dentists in addition to establishing screening programs to achieve early detection of selected malignant tumors. © 2014 Wiley Periodicals, Inc.

EFFECT OF CERTAIN YOGIC ASANAS ON THE PELVIC CONGESTION AND IT'S ANATOMY

PubMed Central

Mishra, Satyendra Prasad; Singh, R.H.

1984-01-01

20 patient including 6 females and 14 males, between 20 years to 30 years of age, with complaints of chronic constipation refractory to various treatments by medicines, belching, sense of heaviness in the lower abdomen or pelvic region, offensive discharge from vagina (leucorrhoea) and bleeding per rectum with discomfort in the region of perineum were observed under instructions and supervision to practice certain yogic exercises for a period of three years. Viparitakarani, Goraksa asana, Uddyana Bandha and Mula Bandha (Nauli, Perineal Shrug) when practiced, relieved these patients were asked not to take any purgatives or laxatives. It was concluded from the present study that these complaints which can be ascribed to poor hemodynamics in the region of pelvis and perineum disappeared and patients showed obvious improvement after practicing these Asanas which reduced pelvic congestion and increased blood flow to the pelvic viscera i.e rectum, anal canal, prostate, uterus, vagina and levator ani and perineal muscles PMID:22557465

Real-time simulation of soft tissue deformation and electrocautery procedures in laparoscopic rectal cancer radical surgery.

PubMed

Sui, Yuan; Pan, Jun J; Qin, Hong; Liu, Hao; Lu, Yun

2017-12-01

Laparoscopic surgery (LS), also referred to as minimally invasive surgery, is a modern surgical technique which is widely applied. The fulcrum effect makes LS a non-intuitive motor skill with a steep learning curve. A hybrid model of tetrahedrons and a multi-layer triangular mesh are constructed to simulate the deformable behavior of the rectum and surrounding tissues in the Position-Based Dynamics (PBD) framework. A heat-conduction based electric-burn technique is employed to simulate the electrocautery procedure. The simulator has been applied for laparoscopic rectum cancer surgery training. From the experimental results, trainees can operate in real time with high degrees of stability and fidelity. A preliminary study was performed to evaluate the realism and usefulness. This prototype simulator has been tested and verified by colorectal surgeons through a pilot study. They believed both the visual and the haptic performance of the simulation are realistic and helpful to enhance laparoscopic skills. Copyright © 2017 John Wiley & Sons, Ltd.

Radiation dose delivery verification in the treatment of carcinoma-cervix

NASA Astrophysics Data System (ADS)

Shrotriya, D.; Kumar, S.; Srivastava, R. N. L.

2015-06-01

The accurate dose delivery to the clinical target volume in radiotherapy can be affected by various pelvic tissues heterogeneities. An in-house heterogeneous woman pelvic phantom was designed and used to verify the consistency and computational capability of treatment planning system of radiation dose delivery in the treatment of cancer cervix. Oncentra 3D-TPS with collapsed cone convolution (CCC) dose calculation algorithm was used to generate AP/PA and box field technique plan. the radiation dose was delivered by Primus Linac (Siemens make) employing high energy 15 MV photon beam by isocenter technique. A PTW make, 0.125cc ionization chamber was used for direct measurements at various reference points in cervix, bladder and rectum. The study revealed that maximum variation between computed and measured dose at cervix reference point was 1% in both the techniques and 3% and 4% variation in AP/PA field and 5% and 4.5% in box technique at bladder and rectum points respectively.

Masked urinary bladder injury with a bullet expulsed spontaneously during voiding.

PubMed

Calışkan, Müjgan; Evren, Ismail; Kabak, Ismail; Atak, Ibrahim; Gökcan, Recai

2011-09-01

We report a case with gunshot to the pelvis. The injury site was the soft tissue between the rectum and urinary bladder. Several days later, the bullet was expulsed spontaneously during voiding. In the literature, only a few case reports have described spontaneous expulsion of an intravesical bullet. A 19-year-old male was wounded on the left hip by gunshot. Radiographic examinations showed a bullet in the pelvis, which was localized in the soft tissue between the rectum and urinary bladder, with no accompanying visceral injury on abdominopelvic computerized tomography. Macroscopic hematuria was noticed after urethral catheterization. Rectosigmoidoscopy and retrograde cystoscopic examinations were both negative. The patient was monitored closely and treated conservatively with no surgical intervention. The urinary catheter was removed on the fifth postoperative day, and the bullet was expulsed spontaneously via the urethra during normal voiding three hours after catheter removal. Thereafter, a retrograde urethrography was performed, which showed no evidence of urinary tract or bladder injury.

Docetaxel-loaded thermosensitive liquid suppository: optimization of rheological properties.

PubMed

Yeo, Woo Hyun; Ramasamy, Thiruganesh; Kim, Dong-Wuk; Cho, Hyuk Jun; Kim, Yong-Il; Cho, Kwan Hyung; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

2013-12-01

The main purpose of this work was to optimize the rheological properties of docetaxel (DCT)-loaded thermosensitive liquid suppositories for rectal administration. DCT-loaded liquid suppositories were prepared by a cold method and characterized in terms of physicochemical and viscoelastic properties. Major formulation parameters including poloxamer (P407) and Tween 80 were optimized to adjust the thermogelling and mucoadhesive properties for rectal administration. Notably, the gel strength and mucoadhesive force significantly increased with the increase in these variables. Furthermore, DCT incorporation did not alter the viscoelastic behavior, and the mean particle size of nanomicelles in it was approximately 16 nm with a distinct spherical shape. The formulation existed as liquid at room temperature and transformed into gel at physiological temperature through the reverse gelation phenomenon. Thus, DCT-loaded thermosensitive liquid suppositories [DCT/P407/P188/Tween 80 (0.25/11/15/10 %)] with optimal gel properties were easy to prepare and administer rectally, and might enable the gel to stay in the rectum without getting out from rectum.

Masculinity and the body: how African American and White men experience cancer screening exams involving the rectum.

PubMed

Winterich, Julie A; Quandt, Sara A; Grzywacz, Joseph G; Clark, Peter E; Miller, David P; Acuña, Joshua; Arcury, Thomas A

2009-12-01

Past research on prostate and colorectal cancer disparities finds that barriers to screening, such as embarrassment and offensiveness, are often reported. Yet none of this literature investigates why. This study uses masculinity and health theory to examine how men experience two common screenings: digital rectal exams (DREs) and colonoscopies. In-depth interviews were conducted with 64 African American and White men from diverse backgrounds, aged 40 to 64, from North Carolina. Regardless of race or education, men experienced DREs more negatively than colonoscopies because penetration with a finger was associated with a gay sexual act. Some men disliked colonoscopies, however, because they associated any penetration as an affront to their masculinity. Because beliefs did not differ by race, future research should focus on structural issues to examine why disparities persist with prostate and colorectal cancer. Recommendations are provided for educational programs and physicians to improve men's experiences with exams that involve the rectum.

Deformable anatomical templates for brachytherapy treatment planning in radiotherapy of cervical cancer

NASA Astrophysics Data System (ADS)

Christensen, Gary E.; Williamson, Jeffrey F.; Chao, K. S. C.; Miller, Michael I.; So, F. B.; Vannier, Michael W.

1997-10-01

This paper describes a new method to register serial, volumetric x-ray computed tomography (CT) data sets for tracking soft-tissue deformation caused by insertion of intracavity brachytherapy applicators to treat cervical cancer. 3D CT scans collected from the same patient with and without a brachytherapy applicator are registered to aid in computation of the radiation dose to tumor and normal tissue. The 3D CT image volume of pelvic anatomy with the applicator. Initial registration is accomplished by rigid alignment of the pelvic bones and non-rigid alignment of gray scale CT data and hand segmentations of the vagina, cervix, bladder, and rectum. A viscous fluid transformation model is used for non-rigid registration to allow for local, non-linear registration of the vagina, cervix, bladder, and rectum without disturbing the rigid registration of the bony pelvis and adjacent structures. Results are presented in which two 3D CT data sets of the same patient - imaged with and without a brachytherapy applicator - are registered.

Design of a rectal probe for diffuse optical spectroscopy imaging for chemotherapy and radiotherapy monitoring

NASA Astrophysics Data System (ADS)

van de Giessen, Martijn; Santoro, Ylenia; Mirzaei Zarandi, Soroush; Pigazzi, Alessio; Cerussi, Albert E.; Tromberg, Bruce J.

2014-03-01

Diffuse optical spectroscopy imaging (DOSI) has shown great potential for the early detection of non-responding tumors during neoadjuvant chemotherapy in breast cancer, already one day after therapy starts. Patients with rectal cancer receive similar chemotherapy treatment. The rectum geometry and tissue properties of healthy and tumor tissue in the rectum and the requirement of surface contact impose constraints on the probe design. In this work we present the design of a DOSI probe with the aim of early chemotherapy/radiotherapy effectiveness detection in rectal tumors. We show using Monte Carlo simulations and phantom measurements that the colon tissue can be characterized reliably using a source-detector separation in the order of 10 mm. We present a design and rapid prototype of a probe for DOSI measurements that can be mounted on a standard laparoscope and that fits through a standard rectoscope. Using predominantly clinically approved components we aim at fast clinical translation.

Segmentation algorithm of colon based on multi-slice CT colonography

NASA Astrophysics Data System (ADS)

Hu, Yizhong; Ahamed, Mohammed Shabbir; Takahashi, Eiji; Suzuki, Hidenobu; Kawata, Yoshiki; Niki, Noboru; Suzuki, Masahiro; Iinuma, Gen; Moriyama, Noriyuki

2012-02-01

CT colonography is a radiology test that looks at people's large intestines(colon). CT colonography can screen many options of colon cancer. This test is used to detect polyps or cancers of the colon. CT colonography is safe and reliable. It can be used if people are too sick to undergo other forms of colon cancer screening. In our research, we proposed a method for automatic segmentation of the colon from abdominal computed Tomography (CT) images. Our multistage detection method extracted colon and spited colon into different parts according to the colon anatomy information. We found that among the five segmented parts of the colon, sigmoid (20%) and rectum (50%) are more sensitive toward polyps and masses than the other three parts. Our research focused on detecting the colon by the individual diagnosis of sigmoid and rectum. We think it would make the rapid and easy diagnosis of colon in its earlier stage and help doctors for analysis of correct position of each part and detect the colon rectal cancer much easier.

Study shows colon and rectal tumors constitute a single type of cancer

Cancer.gov

The pattern of genomic alterations in colon and rectal tissues is the same regardless of anatomic location or origin within the colon or the rectum, leading researchers to conclude that these two cancer types can be grouped as one, according to The Cancer

Optimum Timing for Surgery After Pre-operative Radiotherapy 6 vs 12 Weeks

ClinicalTrials.gov

2015-06-22

Adenocarcinoma of the Rectum; Adenocarcinoma; Adenocarcinoma, Mucinous; Carcinoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Cystic, Mucinous, and Serous; Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases

21 CFR 522.1081 - Chorionic gonadotropin.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... Dosage may be repeated in 14 days if the animal's behavior or examination of the ovaries per rectum... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1081...

21 CFR 522.1081 - Chorionic gonadotropin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... repeated in 14 days if the animal's behavior or examination of the ovaries per rectum indicates retreatment... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1081...

21 CFR 522.1081 - Chorionic gonadotropin.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... Dosage may be repeated in 14 days if the animal's behavior or examination of the ovaries per rectum... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1081...

21 CFR 522.1081 - Chorionic gonadotropin.

Code of Federal Regulations, 2011 CFR

2011-04-01

... repeated in 14 days if the animal's behavior or examination of the ovaries per rectum indicates retreatment... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1081...

Comparison of dosimetric and radiobiological parameters on plans for prostate stereotactic body radiotherapy using an endorectal balloon for different dose-calculation algorithms and delivery-beam modes

NASA Astrophysics Data System (ADS)

Kang, Sang-Won; Suh, Tae-Suk; Chung, Jin-Beom; Eom, Keun-Yong; Song, Changhoon; Kim, In-Ah; Kim, Jae-Sung; Lee, Jeong-Woo; Cho, Woong

2017-02-01

The purpose of this study was to evaluate the impact of dosimetric and radiobiological parameters on treatment plans by using different dose-calculation algorithms and delivery-beam modes for prostate stereotactic body radiation therapy using an endorectal balloon. For 20 patients with prostate cancer, stereotactic body radiation therapy (SBRT) plans were generated by using a 10-MV photon beam with flattening filter (FF) and flattening-filter-free (FFF) modes. The total treatment dose prescribed was 42.7 Gy in 7 fractions to cover at least 95% of the planning target volume (PTV) with 95% of the prescribed dose. The dose computation was initially performed using an anisotropic analytical algorithm (AAA) in the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA) and was then re-calculated using Acuros XB (AXB V. 11.0.34) with the same monitor units and multileaf collimator files. The dosimetric and the radiobiological parameters for the PTV and organs at risk (OARs) were analyzed from the dose-volume histogram. An obvious difference in dosimetric parameters between the AAA and the AXB plans was observed in the PTV and rectum. Doses to the PTV, excluding the maximum dose, were always higher in the AAA plans than in the AXB plans. However, doses to the other OARs were similar in both algorithm plans. In addition, no difference was observed in the dosimetric parameters for different delivery-beam modes when using the same algorithm to generate plans. As a result of the dosimetric parameters, the radiobiological parameters for the two algorithm plans presented an apparent difference in the PTV and the rectum. The average tumor control probability of the AAA plans was higher than that of the AXB plans. The average normal tissue complication probability (NTCP) to rectum was lower in the AXB plans than in the AAA plans. The AAA and the AXB plans yielded very similar NTCPs for the other OARs. In plans using the same algorithms, the NTCPs for delivery-beam modes showed no differences. This study demonstrated that the dosimetric and the radiobiological parameters for the PTV and the rectum affected the dose-calculation algorithms for prostate SBRT using an endorectal balloon. However, the dosimetric and the radiobiological parameters in the AAA and the AXB plans for other OARs were similar. Furthermore, difference between the dosimetric and the radiobiological parameters for different delivery-beam modes were not found when the same algorithm was used to generate the treatment plan.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borot de Battisti, M; Maenhout, M; Lagendijk, J J W

Purpose: To develop adaptive planning with feedback for MRI-guided focal HDR prostate brachytherapy with a single divergent needle robotic implant device. After each needle insertion, the dwell positions for that needle are calculated and the positioning of remaining needles and dosimetry are both updated based on MR imaging. Methods: Errors in needle positioning may occur due to inaccurate needle insertion (caused by e.g. the needle’s bending) and unpredictable changes in patient anatomy. Consequently, the dose plan quality might dramatically decrease compared to the preplan. In this study, a procedure was developed to re-optimize, after each needle insertion, the remaining needlemore » angulations, source positions and dwell times in order to obtain an optimal coverage (D95% PTV>19 Gy) without exceeding the constraints of the organs at risk (OAR) (D10% urethra<21 Gy, D1cc bladder<12 Gy and D1cc rectum<12 Gy). Complete HDR procedures with 6 needle insertions were simulated for a patient MR-image set with PTV, prostate, urethra, bladder and rectum delineated. Random angulation errors, modeled by a Gaussian distribution (standard deviation of 3 mm at the needle’s tip), were generated for each needle insertion. We compared the final dose parameters for the situations (I) without re-optimization and (II) with the automatic feedback. Results: The computation time of replanning was below 100 seconds on a current desk computer. For the patient tested, a clinically acceptable dose plan was achieved while applying the automatic feedback (median(range) in Gy, D95% PTV: 19.9(19.3–20.3), D10% urethra: 13.4(11.9–18.0), D1cc rectum: 11.0(10.7–11.6), D1cc bladder: 4.9(3.6–6.8)). This was not the case without re-optimization (median(range) in Gy, D95% PTV: 19.4(14.9–21.3), D10% urethra: 12.6(11.0–15.7), D1cc rectum: 10.9(8.9–14.1), D1cc bladder: 4.8(4.4–5.2)). Conclusion: An automatic guidance strategy for HDR prostate brachytherapy was developed to compensate errors in needle positioning and improve the dose distribution. Without re-optimization, target coverage and OAR constraints may not be achieved. M. Borot de Battisti is funded by Philips Medical Systems Nederland B.V.; M. Moerland is principal investigator on a contract funded by Philips Medical Systems Nederland B.V.; G. Hautvast and D. Binnekamp are full-time employees of Philips Medical Systems Nederland B.V.« less

Administering a suppository.

PubMed

Higgins, Dan

A suppository is a medicated solid formulation prepared for insertion into the rectum to dissolve at body temperature (Moppet and Parker, 1999). The administration of a suppository requires skill and competence on behalf of the practitioner, as well as compliance with the NMC (2004a) guidelines on the administration of medicines and local drug administration policy.

Pharmacotherapy in the Management of Voiding and Storage Disorders, Including Enuresis and Encopresis

ERIC Educational Resources Information Center

Reiner, William G.

2008-01-01

Enuresis and encopresis are disorders of the bladder and rectum, and this article helps in understanding the neurobiology of lower urinary tract and anorectal function to help in the treatment of these disorders. Treatment for children with these disorders emphasizes either a psychological or pharmacological approach.

Proctalgia fugax.

PubMed

Babb, Richard R

1996-04-01

Preview Severe, episodic pain in the rectum may prompt extensive- and expensive- diagnostic testing. If the cause is proctalgia fugax, such testing is unnecessary and wasteful. The author, a gastroenterologist, offers a guide to prompt recognition of the disorder based on patient history and suggests several therapeutic stategies that may help to relieve the pain.

Targeting MRS-Defined Dominant Intraprostatic Lesions with Inverse-Planned High Dose Rate Brachytherapy

DTIC Science & Technology

2006-02-01

metabolite markers ( choline , citrate, creatine and polyamines): elevation of choline peak and reduction of citrate and creatine peaks in an abnormal... overdose on bladder while the other 3 patients on rectum. Under dosimetric requirement (i) and (ii), in most patients the DIL-boost increased the DIL

Bilateral ‘gut-tie’ in a recently castrated steer

PubMed Central

Haruna, Julius A.; Ortenburger, Art

2006-01-01

Abstract Small intestinal obstruction caused by 2 fibrous bands was found in a steer. Distended small intestine was palpable per rectum. Each band was located bilaterally between the caudal abdominal wall and the pelvic inlet. The compromised portion of intestine was considered nonviable and the animal was euthanized. PMID:16579042

Influence of source batch S{sub K} dispersion on dosimetry for prostate cancer treatment with permanent implants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nuñez-Cumplido, E., E-mail: ejnc-mccg@hotmail.com; Hernandez-Armas, J.; Perez-Calatayud, J.

2015-08-15

Purpose: In clinical practice, specific air kerma strength (S{sub K}) value is used in treatment planning system (TPS) permanent brachytherapy implant calculations with {sup 125}I and {sup 103}Pd sources; in fact, commercial TPS provide only one S{sub K} input value for all implanted sources and the certified shipment average is typically used. However, the value for S{sub K} is dispersed: this dispersion is not only due to the manufacturing process and variation between different source batches but also due to the classification of sources into different classes according to their S{sub K} values. The purpose of this work is tomore » examine the impact of S{sub K} dispersion on typical implant parameters that are used to evaluate the dose volume histogram (DVH) for both planning target volume (PTV) and organs at risk (OARs). Methods: The authors have developed a new algorithm to compute dose distributions with different S{sub K} values for each source. Three different prostate volumes (20, 30, and 40 cm{sup 3}) were considered and two typical commercial sources of different radionuclides were used. Using a conventional TPS, clinically accepted calculations were made for {sup 125}I sources; for the palladium, typical implants were simulated. To assess the many different possible S{sub K} values for each source belonging to a class, the authors assigned an S{sub K} value to each source in a randomized process 1000 times for each source and volume. All the dose distributions generated for each set of simulations were assessed through the DVH distributions comparing with dose distributions obtained using a uniform S{sub K} value for all the implanted sources. The authors analyzed several dose coverage (V{sub 100} and D{sub 90}) and overdosage parameters for prostate and PTV and also the limiting and overdosage parameters for OARs, urethra and rectum. Results: The parameters analyzed followed a Gaussian distribution for the entire set of computed dosimetries. PTV and prostate V{sub 100} and D{sub 90} variations ranged between 0.2% and 1.78% for both sources. Variations for the overdosage parameters V{sub 150} and V{sub 200} compared to dose coverage parameters were observed and, in general, variations were larger for parameters related to {sup 125}I sources than {sup 103}Pd sources. For OAR dosimetry, variations with respect to the reference D{sub 0.1cm{sup 3}} were observed for rectum values, ranging from 2% to 3%, compared with urethra values, which ranged from 1% to 2%. Conclusions: Dose coverage for prostate and PTV was practically unaffected by S{sub K} dispersion, as was the maximum dose deposited in the urethra due to the implant technique geometry. However, the authors observed larger variations for the PTV V{sub 150}, rectum V{sub 100}, and rectum D{sub 0.1cm{sup 3}} values. The variations in rectum parameters were caused by the specific location of sources with S{sub K} value that differed from the average in the vicinity. Finally, on comparing the two sources, variations were larger for {sup 125}I than for {sup 103}Pd. This is because for {sup 103}Pd, a greater number of sources were used to obtain a valid dose distribution than for {sup 125}I, resulting in a lower variation for each S{sub K} value for each source (because the variations become averaged out statistically speaking)« less

A feature alignment score for online cone-beam CT-based image-guided radiotherapy for prostate cancer.

PubMed

Hargrave, Catriona; Deegan, Timothy; Poulsen, Michael; Bednarz, Tomasz; Harden, Fiona; Mengersen, Kerrie

2018-05-17

To develop a method for scoring online cone-beam CT (CBCT)-to-planning CT image feature alignment to inform prostate image-guided radiotherapy (IGRT) decision-making. The feasibility of incorporating volume variation metric thresholds predictive of delivering planned dose into weighted functions, was investigated. Radiation therapists and radiation oncologists participated in workshops where they reviewed prostate CBCT-IGRT case examples and completed a paper-based survey of image feature matching practices. For 36 prostate cancer patients, one daily CBCT was retrospectively contoured then registered with their plan to simulate delivered dose if (a) no online setup corrections and (b) online image alignment and setup corrections, were performed. Survey results were used to select variables for inclusion in classification and regression tree (CART) and boosted regression trees (BRT) modeling of volume variation metric thresholds predictive of delivering planned dose to the prostate, proximal seminal vesicles (PSV), bladder, and rectum. Weighted functions incorporating the CART and BRT results were used to calculate a score of individual tumor and organ at risk image feature alignment (FAS TV _ OAR ). Scaled and weighted FAS TV _ OAR were then used to calculate a score of overall treatment compliance (FAS global ) for a given CBCT-planning CT registration. The FAS TV _ OAR were assessed for sensitivity, specificity, and predictive power. FAS global thresholds indicative of high, medium, or low overall treatment plan compliance were determined using coefficients from multiple linear regression analysis. Thirty-two participants completed the prostate CBCT-IGRT survey. While responses demonstrated consensus of practice for preferential ranking of planning CT and CBCT match features in the presence of deformation and rotation, variation existed in the specified thresholds for observed volume differences requiring patient repositioning or repeat bladder and bowel preparation. The CART and BRT modeling indicated that for a given registration, a Dice similarity coefficient >0.80 and >0.60 for the prostate and PSV, respectively, and a maximum Hausdorff distance <8.0 mm for both structures were predictive of delivered dose ± 5% of planned dose. A normalized volume difference <1.0 and a CBCT anterior rectum wall >1.0 mm anterior to the planning CT anterior rectum wall were predictive of delivered dose >5% of planned rectum dose. A normalized volume difference <0.88, and a CBCT bladder wall >13.5 mm inferior and >5.0 mm posterior to the planning CT bladder were predictive of delivered dose >5% of planned bladder dose. A FAS TV _ OAR >0 is indicative of delivery of planned dose. For calculated FAS TV _ OAR for the prostate, PSV, bladder, and rectum using test data, sensitivity was 0.56, 0.75, 0.89, and 1.00, respectively; specificity 0.90, 0.94, 0.59, and 1.00, respectively; positive predictive power 0.90, 0.86, 0.53, and 1.00, respectively; and negative predictive power 0.56, 0.89, 0.91, and 1.00, respectively. Thresholds for the calculated FAS global of were low <60, medium 60-80, and high >80, with a 27% misclassification rate for the test data. A FAS global incorporating nested FAS TV _ OAR and volume variation metric thresholds predictive of treatment plan compliance was developed, offering an alternative to pretreatment dose calculations to assess treatment delivery accuracy. © 2018 American Association of Physicists in Medicine.

Temperature data analysis for 22 patients with advanced cervical carcinoma treated in Rotterdam using radiotherapy, hyperthermia and chemotherapy: a reference point is needed.

PubMed

Fatehi, D; van der Zee, J; van der Wal, E; Van Wieringen, W N; Van Rhoon, G C

2006-06-01

The growing interest and participation in multi-institutional trials involving deep hyperthermia treatment is an important step towards the further consolidation of hyperthermia as an oncological treatment modality. However, the differences in the clinical procedures of hyperthermia application also raises questions as how to compare the reported temperatures data obtained by the different institutes. In this study our recent developed approach, RHyThM (Rotterdam Hyperthermia Thermal Modulator), has been used for thermal data analysis to investigate the temperature dynamics behaviour of a series of deep hyperthermia treatments. All 22 patients (104 hyperthermia treatments) with locally advanced cervical carcinoma who participated in a feasibility study for treatment with a three-modality therapy were selected. The patients received mega-voltage external beam radiotherapy to the pelvis in daily fractions of 2 Gy five times a week to a total dose of 46 Gy and additional brachytherapy, at least four courses of weekly cisplatin (40 mg m-2) and five sessions of weekly loco regional deep hyperthermia treatments with the BSD2000-3D with the Sigma 60 or the Sigma-eye applicators at frequencies 70-120 MHz. Using RHyThM tissue type was defined along the insertion length, based on the CT scan information in radiotherapy position, for each single treatment. A step change in the slope of the profile of the first temperature map was identified to verify the insertion length of the thermometry catheter and precise location of the transition between in- and outside the body. Data analysis was performed based on the temperature readout provided by RHyThM. The temperature and RF-power data of 97 treatments could be analysed. The intra-vaginal temperature indices were slightly lower than those for bladder and rectum. The average T50 (median temperature) in all lumens, i.e. bladder, vagina and rectum, was 40.4 +/- 0.6 degrees Celsius. The average vagina all lumen T50 was 40.0 +/- 0.8 degrees Celsius. The average bladder and rectum all lumen T50 was 40.6 +/- 0.7 degrees Celsius and 40.5 +/- 0.6, respectively. When the analysis was restricted to the deepest 5 cm of the vagina lumen, the average T50 was 39.8 +/- 0.9 degrees Celsius. Good correlation exists between the various temperature indices like T20, T50 and T90, for all lumen measurements in bladder, vagina and rectum. No correlation was found between temperature indices and treatment number. For the complete patient population, no relationship was found between T50 and net integrated RF-power applied. In an explorative analysis on individual patients a positive correlation coefficient or trend was found in 14 patients between normalized net integrated RF-power and vagina T50. Average all lumen T50 for bladder, vagina and rectum differ less than 1 degrees Celsius, indicating that a large volume was heated relatively homogeneously. The vagina T50 value depends on how many measurement points are included for the analysis. In this group of patients the vagina T50 of the first treatment is not a good measure to discriminate between patients with 'heatable' and 'non-heatable' tumours. In order to compare temperature data reported by different institutes dealing with the same group of patients, one needs a strict and clear agreement on which temperature measurements or reference point(s) that should be included in the analysis.

Leiomyoma of the anal canal: report of two cases.

PubMed

Witz, M; Bernheim, J; Griffel, B; Dinbar, A

1986-10-01

Leiomyoma of the rectum and anal canal is an unusual clinical entity. Generally, it does not produce any clinical signs and in most cases it is discovered incidentally in the course of routine rectal examination. The clinical presentation, diagnosis, and surgical treatment are described in two presented cases of anal canal leiomyoma.

ABSORPTION OF MICROWAVE RADIATION BY THE ANESTHETIZED RAT: ELECTROMAGNETIC AND THERMAL HOTSPOTS IN BODY AND TAIL

EPA Science Inventory

Anatomic variability in the deposition of radio frequency electromagnetic energy in mammals as been well documented. ecent study [D'Andrea et al. 1985] reported specific absorption rat (SAR) hotspots in the brain, rectum, and tail of rat carcasses exposed to 360- and to 2,450-MHz...

Impact of Aids on the Military Recruitment: Interviews with Seropositive New Recruits

DTIC Science & Technology

1991-06-30

or rectum. For the purposes of this interview, sex does not include kissing, touching, or masturbation . 1. How old were you when you sexual...of this interview, sex does not include kissing, touching, or masturbation , 1. How old were you when you sexual intercoursfor the first time? [Age 2

Agreement between auricular and rectal measurements of body temperature in healthy cats.

PubMed

Sousa, Marlos G; Carareto, Roberta; Pereira-Junior, Valdo A; Aquino, Monally C C

2013-04-01

Measurement of body temperature is a routine part of the clinical assessment of a patient. However, this procedure may be time-consuming and stressful to most animals because the standard site of temperature acquisition remains the rectal mucosa. Although an increasing number of clinicians have been using auricular temperature to estimate core body temperature, evidence is still lacking regarding agreement between these two methods in cats. In this investigation, we evaluated the agreement between temperatures measured in the rectum and ear in 29 healthy cats over a 2-week period. Temperatures were measured in the rectum (using digital and mercury-in-glass thermometers) and ear once a day for 14 consecutive days, producing 406 temperature readings for each thermometer. Mean temperature and confidence intervals were similar between methods, and Bland-Altman plots showed small biases and narrow limits of agreement acceptable for clinical purposes. The interobserver variability was also checked, which indicated a strong correlation between two near-simultaneous temperature readings. Results are consistent with auricular thermometry being a reliable alternative to rectal thermometry for assessing core body temperature in healthy cats.

Minimally Invasive Repair of a Prostatorectal Fistula with an Over-the-Scope Rectal Clip

PubMed Central

Schmidt-Heikenfeld, Ekkehard; Degener, Stephan; Roosen, Alexander; Boy, Anselm

2017-01-01

Abstract Background: Fistulae between the prostatic urethra and the rectum are rare. They may result from prostatic or rectal surgery. Predisposing factors are previous radiation or immunosuppression. The repair of such fistulae usually involves major surgery. Recently, clips that can be deployed over an endoscope have been developed to close gastrointestinal fistulae or access points for natural orifice surgery. We report the first case of effective treatment of a prostatorectal fistula with a rectal “over-the-scope” clip. Case Presentation: A 64-year-old man under chronic immunosuppression presented with an iatrogenic fistula between the prostatic urethra and the rectum after transurethral resection of the prostate. A transverse colostomy was placed but the fistula failed to heal conservatively. The fistula was effectively closed with an endorectal clip. Six weeks after the procedure, spontaneous micturition was started. Two weeks further, the colostomy was reversed. At 32 months of follow-up, the remains closed, micturition is unimpaired. Conclusion: In select cases of prostatorectal fistula, an endorectal clip may be effectively used for closure. PMID:29098198

Ulcerative colitis: pathogenesis, diagnosis, and current treatment.

PubMed

Griffel, L H; Das, K M

1996-01-01

Ulcerative colitis is a chronic inflammatory disease of the colon that affects the rectum and a variable length of contiguous colon. The disease is characterized by rectal bleeding and diarrhea during periods of exacerbation; these symptoms usually abate with treatment. The pathogenic mechanism of ulcerative colitis is believed to be an aberrant immune response in which antibodies are formed against colonic epithelial protein(s). The disease usually presents during the second and third decades of life, with a smaller peak after the age of 60 years. There is a genetic component to ulcerative colitis, with a higher incidence among family members and, particularly, first-degree relatives. Diagnosis depends on several factors, most notably symptoms, demonstration of uniformly inflamed mucosa beginning in the rectum, and exclusion of other causes of colitis, such as infection. There is no medical cure for ulcerative colitis, but medical therapy is effective and can improve or eliminate symptoms in more than 80% of patients. Surgery offers a cure but carries the high price of total colectomy. New surgical methods, such as ileoanal anastomosis, allow for maintenance of bowel continuity and better patient satisfaction.

Genotype-guided Dosing of mFOLFIRINOX Chemotherapy in Patients With Previously Untreated Advanced Gastrointestinal Malignancies

ClinicalTrials.gov

2018-03-08

Acinar Cell Adenocarcinoma of the Pancreas; Adenocarcinoma of the Gallbladder; Adenocarcinoma of Unknown Primary; Adult Primary Cholangiocellular Carcinoma; Advanced Adult Primary Liver Cancer; Cholangiocarcinoma of the Extrahepatic Bile Duct; Cholangiocarcinoma of the Gallbladder; Diffuse Adenocarcinoma of the Stomach; Duct Cell Adenocarcinoma of the Pancreas; Intestinal Adenocarcinoma of the Stomach; Localized Unresectable Adult Primary Liver Cancer; Metastatic Carcinoma of Unknown Primary; Metastatic Extrahepatic Bile Duct Cancer; Mixed Adenocarcinoma of the Stomach; Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Newly Diagnosed Carcinoma of Unknown Primary; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage III Pancreatic Cancer; Stage IIIA Colon Cancer; Stage IIIA Gallbladder Cancer; Stage IIIA Gastric Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Gallbladder Cancer; Stage IIIB Gastric Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Gastric Cancer; Stage IIIC Rectal Cancer; Stage IV Gastric Cancer; Stage IV Pancreatic Cancer; Stage IVA Colon Cancer; Stage IVA Gallbladder Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Gallbladder Cancer; Stage IVB Rectal Cancer; Unresectable Extrahepatic Bile Duct Cancer

Intestinal stoma in patients with colorectal cancer from the perspective of 20-year period of clinical observation.

PubMed

Banaszkiewicz, Zbigniew; Woda, Łukasz P; Zwoliński, Tomasz; Tojek, Krzysztof; Jarmocik, Paweł; Jawień, Arkadiusz

2015-01-01

Intestinal stoma is a procedure most often performed in patients with colorectal cancer. To identify the percentage of patients with colorectal cancer in which the intestinal stoma was performed. We retrospectively analysed 443 patients treated during a 20-year period (1994-2013) due to colorectal cancer, in which the intestinal stoma was made during the first surgical intervention. In the second analysed decade, a significant decrease in the percentage of created stomas, definitive stomas in particular, was observed. Stomas were made significantly more often in patients with a tumour located in the rectum, the left half of the colon, and in patients undergoing urgent surgeries. An increased incidence of intestinal stomas was associated with a higher severity of illness and higher proportion of unresectable and non-radical procedures. The definitive stomas were significantly more often made in men and in patients with tumours located in the rectum, whereas temporary stomas were created significantly more often in patients undergoing urgent operations. In the last decade (2004-2013) the number of intestinal stomas in patients operated due to colorectal cancer was significantly reduced.

Comment on 'Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study'.

PubMed

Valdes, Gilmer; Interian, Yannet

2018-03-15

The application of machine learning (ML) presents tremendous opportunities for the field of oncology, thus we read 'Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study' with great interest. In this article, the authors used state of the art techniques: a pre-trained convolutional neural network (VGG-16 CNN), transfer learning, data augmentation, drop out and early stopping, all of which are directly responsible for the success and the excitement that these algorithms have created in other fields. We believe that the use of these techniques can offer tremendous opportunities in the field of Medical Physics and as such we would like to praise the authors for their pioneering application to the field of Radiation Oncology. That being said, given that the field of Medical Physics has unique characteristics that differentiate us from those fields where these techniques have been applied successfully, we would like to raise some points for future discussion and follow up studies that could help the community understand the limitations and nuances of deep learning techniques.

Intraoperative ultrasound in colorectal surgery.

PubMed

Greif, Franklin; Aranovich, David; Hananel, Nissim; Knizhnik, Mikhail; Belenky, Alexander

2009-09-01

To assess the accuracy of intraoperative ultrasound (IOUS) as a localizing technique for colorectal resections, and its impact on surgical management. Twenty-five patients (15 men and 10 women; mean age, 74.4 years) with early cancers (p T1), or polyps, not amenable to endoscopic removal were selected. IOUS was used as a sole method of intraoperative localization. Its performance was evaluated through review of preoperative colonoscopy reports, intraoperative findings, histopathology reports, and clinical follow-up. The lesions were situated in the cecum (n = 5), ascending colon (n = 3), transverse colon (n = 4), descending colon (n = 7), and rectum (n = 6). IOUS technique allowed correct localization in 24 of 25 patients, visualization of the bowel wall, and its penetration by malignant tumors. In rectal lesions, IOUS showed clearly the tumor and its margin, which facilitated performance sphincter-sparing procedure. In patients with small polyps and early cancers of colon and rectum, IOUS may be effectively used as a sole method of intraoperative localization and provide additional information that may alter decision making with regard to surgical technique. (c) 2009 Wiley Periodicals, Inc.

Impact of radiation attenuation by a carbon fiber couch on patient dose verification

NASA Astrophysics Data System (ADS)

Yu, Chun-Yen; Chou, Wen-Tsae; Liao, Yi-Jen; Lee, Jeng-Hung; Liang, Ji-An; Hsu, Shih-Ming

2017-02-01

The aim of this study was to understand the difference between the measured and calculated irradiation attenuations obtained using two algorithms and to identify the influence of couch attenuation on patient dose verification. We performed eight tests of couch attenuation with two photon energies, two longitudinal couch positions, and two rail positions. The couch attenuation was determined using a radiation treatment planning system. The measured and calculated attenuations were compared. We also performed 12 verifications of head-and-neck and rectum cases by using a Delta phantom. The dose deviation (DD), distance to agreement (DTA), and gamma index of pencil-beam convolution (PBC) verifications were nearly the same. The agreement was least consistent for the anisotropic analytical algorithm (AAA) without the couch for the head-and-neck case, in which the DD, DTA, and gamma index were 74.4%, 99.3%, and 89%, respectively; for the rectum case, the corresponding values were 56.2%, 95.1%, and 92.4%. We suggest that dose verification should be performed using the following three metrics simultaneously: DD, DTA, and the gamma index.

The clinical value of 201Tl per rectum scintigraphy in the work-up of patients with alcoholic liver disease.

PubMed

Urbain, D; Reding, P; Georges, B; Thys, O; Ham, H R

1986-01-01

The clinical value of thallium 201 per rectum scintigraphy in the work-up of patients with alcoholic liver disease was evaluated using data obtained in 104 patients. The 25th min ratio of heart to liver activities was used as an index of portal systemic shunting. This ratio was found to be normal in alcoholic patients with normal liver biopsy and also in those presenting only steatosis. It was slightly higher in patients with liver fibrosis and significantly higher values were observed in patients with liver cirrhosis. High values of the ratio were associated with a higher risk of portal systemic encephalopathy and/or gastrointestinal bleeding. The prognostic value of the test was supported by the fact that good correlations were observed between the ratio and widely accepted prognostic scores such as the Child score or the Orrego index. Moreover, high ratios were associated with an increased mortality risk at one year. We conclude that this simple test is interesting in the screening of cirrhotics at risk of encephalopathy, gastrointestinal hemorrhage, or early death.

Step-up training for colorectal and gastric ESD and the challenge of ESD training in the proximal colon: results from a German Center.

PubMed

Ebigbo, Alanna; Probst, Andreas; Römmele, Christoph; Messmann, Helmut

2018-05-01

The endoscopic submucosal dissection (ESD) of cancerous and precancerous lesions in the gastrointestinal (GI) tract is an effective but difficult-to-learn procedure, especially for Western endoscopists. We developed a step-up training protocol and evaluated its outcome on a single endoscopist using specific performance measures. The training protocol included a 12-month period of 50 observational and supervised ESD cases as well as 24 animal procedures. After completion of the protocol, ESD competency was evaluated in the first 30 independent ESD cases. Majority of lesions were located in the stomach and rectum. Performance measures included R0-resection rate, complication rate and resection speed. R0 resection rate was 93 %, complication rate was 7 % and median resection speed was 6,77 cm 2 /h. 1 case of delayed perforation with subsequent hemicolectomy occurred in the descending colon. The ESD step-up training protocol used in this study on a single endoscopist showed excellent outcomes for lesions in the rectum and stomach. However, ESD training in the upper colon remains a challenge.

Dosimetric comparison of intensity modulated radiotherapy and three-dimensional conformal radiotherapy in patients with gynecologic malignancies: a systematic review and meta-analysis

PubMed Central

2012-01-01

Background To quantitatively evaluate the safety and related-toxicities of intensity modulated radiotherapy (IMRT) dose–volume histograms (DVHs), as compared to the conventional three-dimensional conformal radiotherapy (3D-CRT), in gynecologic malignancy patients by systematic review of the related publications and meta-analysis. Methods Relevant articles were retrieved from the PubMed, Embase, and Cochrane Library databases up to August 2011. Two independent reviewers assessed the included studies and extracted data. Pooled average percent irradiated volumes of adjacent non-cancerous tissues were calculated and compared between IMRT and 3D-CRT for a range of common radiation doses (5-45Gy). Results In total, 13 articles comprised of 222 IMRT-treated and 233 3D-CRT-treated patients were included. For rectum receiving doses ≥30 Gy, the IMRT pooled average irradiated volumes were less than those from 3D-CRT by 26.40% (30 Gy, p = 0.004), 27.00% (35 Gy, p = 0.040), 37.30% (40 Gy, p = 0.006), and 39.50% (45 Gy, p = 0.002). Reduction in irradiated small bowel was also observed for IMRT-delivered 40 Gy and 45 Gy (by 17.80% (p = 0.043) and 17.30% (p = 0.012), respectively), as compared with 3D-CRT. However, there were no significant differences in the IMRT and 3D-CRT pooled average percent volumes of irradiated small bowel or rectum from lower doses, or in the bladder or bone marrow from any of the doses. IMRT-treated patients did not experience more severe acute or chronic toxicities than 3D-CRT-treated patients. Conclusions IMRT-delivered high radiation dose produced significantly less average percent volumes of irradiated rectum and small bowel than 3D-CRT, but did not differentially affect the average percent volumes in the bladder and bone marrow. PMID:23176540

Rapid Dissemination of SIV Follows Multisite Entry after Rectal Inoculation

PubMed Central

Prétet, Jean-Luc; Michel-Salzat, Alice; Messent, Valérie; Bogdanova, Anna; Couëdel-Courteille, Anne; Souil, Evelyne; Cheynier, Rémi; Butor, Cécile

2011-01-01

Receptive ano-rectal intercourse is a major cause of HIV infection in men having sex with men and in heterosexuals. Current knowledge of the mechanisms of entry and dissemination during HIV rectal transmission is scarce and does not allow the development of preventive strategies. We investigated the early steps of rectal infection in rhesus macaques inoculated with the pathogenic isolate SIVmac251 and necropsied four hours to nine days later. All macaques were positive for SIV. Control macaques inoculated with heat-inactivated virus were consistently negative for SIV. SIV DNA was detected in the rectum as early as four hours post infection by nested PCR for gag in many laser-microdissected samples of lymphoid aggregates and lamina propria but never in follicle-associated epithelium. Scarce SIV antigen positive cells were observed by immunohistofluorescence in the rectum, among intraepithelial and lamina propria cells as well as in clusters in lymphoid aggregates, four hours post infection and onwards. These cells were T cells and non-T cells that were not epithelial cells, CD68+ macrophages, DC-SIGN+ cells or fascin+ dendritic cells. DC-SIGN+ cells carried infectious virus. Detection of Env singly spliced mRNA in the mucosa by nested RT-PCR indicated ongoing viral replication. Strikingly, four hours post infection colic lymph nodes were also infected in all macaques as either SIV DNA or infectious virus was recovered. Rapid SIV entry and dissemination is consistent with trans-epithelial transport. Virions appear to cross the follicle-associated epithelium, and also the digestive epithelium. Viral replication could however be more efficient in lymphoid aggregates. The initial sequence of events differs from both vaginal and oral infections, which implies that prevention strategies for rectal transmission will have to be specific. Microbicides will need to protect both digestive and follicle-associated epithelia. Vaccines will need to induce immunity in lymph nodes as well as in the rectum. PMID:21573012

Development of In Situ Gelling and Bio Adhesive 5-Fluorouracil Enema

PubMed Central

Wang, Lu-Lu; Zheng, Wen-Sheng; Chen, Shao-Hua; Fang, Xia-Qin

2013-01-01

In this study, a novel 5-Fluorouracil (5-FU) enema with good bio adhesion and temperature sensitivity was developed using in situ gelling technology. The preparation was formulated as a free-flowing liquid before use, while a layer of gel film was quickly formed when administered in the rectum, with a large contact surface area. It also demonstrated good biocompatibility, appropriate gel strength and bio adhesive force with excellent adhesion to rectal mucosa and prolonged action time, allowing more effective drug absorption and diffusion to surrounding tissues. Poloxamer 407 and poloxamer 188 were applied to adjust the gelling temperature. With the addition of carbopol and polycarbophil (bio adhesive substances), the solubility of 5-FU and gel strength increased, the temperature of gelation and the surface area of drug contact on mucous epithelium decreased. Decreased adhesive force between the preparation and the mucous membrane of the rectum was demonstrated with improving carbopol and polycarbophil’s concentration. In vitro release demonstrated that 5-FU in situ gelling enema with different bases had a rapid and almost complete drug release. We used an optimized formulation of P407/P188/polycarbophil/5-FU (17/2.5/0.2/1.0) for animal experiments. The result showed that the drug evenly covered the surface of the rectum and there was no leakage in 6 hours. The in situ gelling enema showed significantly higher rectal tissue levels of 5-FU compared with suppository and intravenous administration, indicating that 5-FU could be well absorbed due to the enlarged releasing area, longer retention time and larger amount of dissolved active ingredients. Systemically, 5-FU levels in the enema group were similar to those in the suppository group and significantly lower than the intravenous group. The enema was not associated with morphological damage to rectal tissue. These results suggest that the bio adhesive and in situ gelling enema could be a more effective rectal delivery system of 5-FU. PMID:23976976

Development of in situ gelling and bio adhesive 5-Fluorouracil enema.

PubMed

Wang, Lu-Lu; Zheng, Wen-Sheng; Chen, Shao-Hua; Fang, Xia-Qin

2013-01-01

In this study, a novel 5-Fluorouracil (5-FU) enema with good bio adhesion and temperature sensitivity was developed using in situ gelling technology. The preparation was formulated as a free-flowing liquid before use, while a layer of gel film was quickly formed when administered in the rectum, with a large contact surface area. It also demonstrated good biocompatibility, appropriate gel strength and bio adhesive force with excellent adhesion to rectal mucosa and prolonged action time, allowing more effective drug absorption and diffusion to surrounding tissues. Poloxamer 407 and poloxamer 188 were applied to adjust the gelling temperature. With the addition of carbopol and polycarbophil (bio adhesive substances), the solubility of 5-FU and gel strength increased, the temperature of gelation and the surface area of drug contact on mucous epithelium decreased. Decreased adhesive force between the preparation and the mucous membrane of the rectum was demonstrated with improving carbopol and polycarbophil's concentration. In vitro release demonstrated that 5-FU in situ gelling enema with different bases had a rapid and almost complete drug release. We used an optimized formulation of P407/P188/polycarbophil/5-FU (17/2.5/0.2/1.0) for animal experiments. The result showed that the drug evenly covered the surface of the rectum and there was no leakage in 6 hours. The in situ gelling enema showed significantly higher rectal tissue levels of 5-FU compared with suppository and intravenous administration, indicating that 5-FU could be well absorbed due to the enlarged releasing area, longer retention time and larger amount of dissolved active ingredients. Systemically, 5-FU levels in the enema group were similar to those in the suppository group and significantly lower than the intravenous group. The enema was not associated with morphological damage to rectal tissue. These results suggest that the bio adhesive and in situ gelling enema could be a more effective rectal delivery system of 5-FU.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, JY; Hong, DL

Purpose: To investigate the impact of bladder filling status of the organs at risk (OARs) on dose distribution during intensity modulated radiotherapy (IMRT) for cervical cancer patients. Methods: Twelve cervical cancer patients treated with IMRT were selected for this study. The prescription dose was 45Gy/25 fractions with the 6 MV photon beam. All patients performed two CT scans, one with an empty bladder, the other one with bladder filled. For the registration of two CT scans, the fusion was automatically carried out upon the bony anatomy. The OARs (bladder, rectum, pelvic bone and small intestine) were delineated to planning CTmore » to evaluate the dose distributions. These dose distributions were compared between empty bladder and bladder filling. Results: The bladder volume with empty bladder and bladder filling was 403.2±124.13cc and 101.4±87.5cc, respectively. There were no statistical differences between empty bladder and bladder filling in the mean value of pelvic bone V10Gy, V20Gy, V40Gy; rectum V40Gy and V45Gy. The bladder V40Gy and V45Gy were lower in the bladder filling group than in the empty bladder group (63.7%±5.8% vs 87.5%±7.8%, 45.1%±9.5% vs 62.4%±11.8%, respectively). The V45Gy for small intestine in the bladder filling group was significantly less than the empty bladder group (146.7cc±95.3cc vs 245.7cc±101.8cc). Conclusion: Our study finds that the bladder filling status did not have a significant impact on dose distribution in the rectum and pelvic bone. However, the changes of bladder filling have a large impact on bladder and small intestine doses. A full bladder is strongly recommended during treatment for cervical cancer patients.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasquier, David; Lacornerie, Thomas; Vermandel, Maximilien

Purpose: Target-volume and organ-at-risk delineation is a time-consuming task in radiotherapy planning. The development of automated segmentation tools remains problematic, because of pelvic organ shape variability. We evaluate a three-dimensional (3D), deformable-model approach and a seeded region-growing algorithm for automatic delineation of the prostate and organs-at-risk on magnetic resonance images. Methods and Materials: Manual and automatic delineation were compared in 24 patients using a sagittal T2-weighted (T2-w) turbo spin echo (TSE) sequence and an axial T1-weighted (T1-w) 3D fast-field echo (FFE) or TSE sequence. For automatic prostate delineation, an organ model-based method was used. Prostates without seminal vesicles were delineatedmore » as the clinical target volume (CTV). For automatic bladder and rectum delineation, a seeded region-growing method was used. Manual contouring was considered the reference method. The following parameters were measured: volume ratio (Vr) (automatic/manual), volume overlap (Vo) (ratio of the volume of intersection to the volume of union; optimal value = 1), and correctly delineated volume (Vc) (percent ratio of the volume of intersection to the manually defined volume; optimal value 100). Results: For the CTV, the Vr, Vo, and Vc were 1.13 ({+-}0.1 SD), 0.78 ({+-}0.05 SD), and 94.75 ({+-}3.3 SD), respectively. For the rectum, the Vr, Vo, and Vc were 0.97 ({+-}0.1 SD), 0.78 ({+-}0.06 SD), and 86.52 ({+-}5 SD), respectively. For the bladder, the Vr, Vo, and Vc were 0.95 ({+-}0.03 SD), 0.88 ({+-}0.03 SD), and 91.29 ({+-}3.1 SD), respectively. Conclusions: Our results show that the organ-model method is robust, and results in reproducible prostate segmentation with minor interactive corrections. For automatic bladder and rectum delineation, magnetic resonance imaging soft-tissue contrast enables the use of region-growing methods.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tien, C; Brewer, M; Studenski, M

Purpose: Dynamic-jaw tracking maximizes the area blocked by both jaw and MLC in RapidArc. We developed a method to quantify jaw tracking. Methods: An Eclipse Scripting API (ESAPI) was used to export beam parameters for each arc’s control points. The specific beam parameters extracted were: gantry angle, control point number, meterset, x-jaw positions, y-jaw positions, MLC bank-number, MLC leaf-number, and MLC leaf-position. Each arc contained 178 control points with 120 MLC positions. MATLAB routines were written to process these parameters in order to calculate both the beam aperture (unblocked) size for each control point. An average aperture size was weightedmore » by meterset. Jaw factor was defined as the ratio between dynamic-jaw to static-jaw aperture size. Jaw factor was determined for forty retrospectively replanned patients treated with static-jaw delivery sites including lung, brain, prostate, H&N, rectum, and bladder. Results: Most patients had multiple arcs and reduced-field boosts, resulting in 151 fields. Of these, the lowest (0.4722) and highest (0.9622) jaw factor was observed in prostate and rectal cases, respectively. The median jaw factor was 0.7917 meaning there is the potential unincreased blocking by 20%. Clinically, the dynamic-jaw tracking represents an area surrounding the target which would receive MLC-only leakage transmission of 1.68% versus 0.1% with jaws. Jaw-tracking was more pronounced at areas farther from the target. In prostate patients, the rectum and bladder had 5.5% and 6.3% lower mean dose, respectively; the structures closer to the prostate such as the rectum and bladder both had 1.4% lower mean dose. Conclusion: A custom ESAPI script was coupled with a MATLAB routine in order to extract beam parameters from static-jaw plans and their replanned dynamic-jaw deliveries. The effects were quantified using jaw factor which is the ratio between the meterset weighted aperture size for dynamic-jaw fields versus static-jaw fields.« less

Do Intermediate Radiation Doses Contribute to Late Rectal Toxicity? An Analysis of Data From Radiation Therapy Oncology Group Protocol 94-06

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tucker, Susan L., E-mail: sltucker@mdanderson.org; Dong, Lei; Michalski, Jeff M.

2012-10-01

Purpose: To investigate whether the volumes of rectum exposed to intermediate doses, from 30 to 50 Gy, contribute to the risk of Grade {>=}2 late rectal toxicity among patients with prostate cancer receiving radiotherapy. Methods and Materials: Data from 1009 patients treated on Radiation Therapy Oncology Group protocol 94-06 were analyzed using three approaches. First, the contribution of intermediate doses to a previously published fit of the Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) model was determined. Next, the extent to which intermediate doses provide additional risk information, after taking the LKB model into account, was investigated. Third, the proportionmore » of rectum receiving doses higher than a threshold, VDose, was computed for doses ranging from 5 to 85 Gy, and a multivariate Cox proportional hazards model was used to determine which of these parameters were significantly associated with time to Grade {>=}2 late rectal toxicity. Results: Doses <60 Gy had no detectable impact on the fit of the LKB model, as expected on the basis of the small estimate of the volume parameter (n = 0.077). Furthermore, there was no detectable difference in late rectal toxicity among cohorts with similar risk estimates from the LKB model but with different volumes of rectum exposed to intermediate doses. The multivariate Cox proportional hazards model selected V75 as the only value of VDose significantly associated with late rectal toxicity. Conclusions: There is no evidence from these data that intermediate doses influence the risk of Grade {>=}2 late rectal toxicity. Instead, the critical doses for this endpoint seem to be {>=}75 Gy. It is hypothesized that cases of Grade {>=}2 late rectal toxicity occurring among patients with V75 less than approximately 12% may be due to a 'background' level of risk, likely due mainly to biological factors.« less

Muscle complex saving posterior sagittal anorectoplasty.

PubMed

Zaiem, Maher; Zaiem, Feras

2017-05-01

Posterior sagittal anorectoplasty (PSARP) published by DeVries and Peña in 1982 had become the preferred surgical technique for the management of anorectal malformations (ARM). The original technique is based upon complete exposure of the anorectal region by means of a median sagittal incision that runs from the sacrum to the anal dimple, cutting through all muscle structures behind the rectum by dividing the levator muscle and the muscle complex. Then, the rectum is located in front of the levator and within the limits of the muscle complex. In this review, we described Muscle Complex Saving-Posterior Sagittal Anorectoplasty (MCS-PSARP), which is a less invasive technique that consists of keeping this funnel-shaped muscle complex completely intact and not divided, and pulling the rectum through this funnel, toward fixing the new anus to the skin. This technique aimed both to respect the lower part of the sphincter mechanism consisting of the muscle complex, and to avoid the disturbance of this important structure by dividing and resuturing it. We presented six cases of male patients who were born with anorectal malformation (ARM) and underwent MCS-PSARP. The surgical technique proved to be feasible to achieve the dissection of the rectal pouch and the division of the rectourethral fistula in all patients, by opening only the upper part of the sphincter mechanism, the levator muscle, and keeping the lower part consisting of intact muscle complex. The early results in our series are encouraging; however, long-term functional outcomes of these patients are awaited. The surgical tips were also discussed. This proposed approach in the management of anorectal malformation cases provides an opportunity to maximize preservation of the existing continence mechanisms. It preserves the muscle complex components of the levator muscle intact, allowing a better function of the continence mechanism. Copyright © 2016 Elsevier Inc. All rights reserved.

SU-F-T-18: The Importance of Immobilization Devices in Brachytherapy Treatments of Vaginal Cuff

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shojaei, M; Dumitru, N; Pella, S

2016-06-15

Purpose: High dose rate brachytherapy is a highly localized radiation therapy that has a very high dose gradient. Thus one of the most important parts of the treatment is the immobilization. The smallest movement of the patient or applicator can result in dose variation to the surrounding tissues as well as to the tumor to be treated. We will revise the ML Cylinder treatments and their localization challenges. Methods: A retrospective study of 25 patients with 5 treatments each looking into the applicator’s placement in regard to the organs at risk. Motion possibilities for each applicator intra and inter fractionationmore » with their dosimetric implications were covered and measured in regard with their dose variance. The localization immobilization devices used were assessed for the capability to prevent motion before and during the treatment delivery. Results: We focused on the 100% isodose on central axis and a 15 degree displacement due to possible rotation analyzing the dose variations to the bladder and rectum walls. The average dose variation for bladder was 15% of the accepted tolerance, with a minimum variance of 11.1% and a maximum one of 23.14% on the central axis. For the off axis measurements we found an average variation of 16.84% of the accepted tolerance, with a minimum variance of 11.47% and a maximum one of 27.69%. For the rectum we focused on the rectum wall closest to the 120% isodose line. The average dose variation was 19.4%, minimum 11.3% and a maximum of 34.02% from the accepted tolerance values Conclusion: Improved immobilization devices are recommended. For inter-fractionation, localization devices are recommended in place with consistent planning in regards with the initial fraction. Many of the present immobilization devices produced for external radiotherapy can be used to improve the localization of HDR applicators during transportation of the patient and during treatment.« less

SU-E-T-332: Dosimetric Impact of Photon Energy and Treatment Technique When Knowledge Based Auto-Planning Is Implemented in Radiotherapy of Localized Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Z; Kennedy, A; Larsen, E

2015-06-15

Purpose: The aim of this study was to investigate the dosimetric impact of the combination of photon energy and treatment technique on radiotherapy of localized prostate cancer when knowledge based planning was used. Methods: A total of 16 patients with localized prostate cancer were retrospectively retrieved from database and used for this study. For each patient, four types of treatment plans with different combinations of photon energy (6X and 10X) and treatment techniques (7-field IMRT and 2-arc VMAT) were created using a prostate DVH estimation model in RapidPlan™ and Eclipse treatment planning system (Varian Medical System). For any beam arrangement,more » DVH objectives and weighting priorities were generated based on the geometric relationship between the OAR and PTV. Photon optimization algorithm was used for plan optimization and AAA algorithm was used for final dose calculation. Plans were evaluated in terms of the pre-defined dosimetric endpoints for PTV, rectum, bladder, penile bulb, and femur heads. A Student’s paired t-test was used for statistical analysis and p > 0.05 was considered statistically significant. Results: For PTV, V95 was statistically similar among all four types of plans, though the mean dose of 10X plans was higher than that of 6X plans. VMAT plans showed higher heterogeneity index than IMRT plans. No statistically significant difference in dosimetry metrics was observed for rectum, bladder, and penile bulb among plan types. For left and right femur, VMAT plans had a higher mean dose than IMRT plans regardless of photon energy, whereas the maximum dose was similar. Conclusion: Overall, the dosimetric endpoints were similar regardless of photon energy and treatment techniques when knowledge based auto planning was used. Given the similarity in dosimetry metrics of rectum, bladder, and penile bulb, the genitourinary and gastrointestinal toxicities should be comparable among the selections of photon energy and treatment techniques.« less

Fluorescent diagnostics of epithelial neoplasms of different colon parts.

PubMed

Korneva, Yulia S; Dorosevich, Alexander E; Maryakhina, Valeriya S

2017-10-01

Changes in the biochemical composition of the tissue during colon cancer progression usually precede morphological changes registered by light microscopy. These changes are very sensitive and may be used for diagnostics in difficult cases, when it is impossible to obtain sufficient amount of material during colonoscopy. The aim of the study is analysis of spectral characteristics of sporadic adenomas and tumors in different parts of colon for improving tumors diagnostics in disputable cases. The spectra of fluorescence excitation of histological sections from 78 patients with colon cancer (adenocarcinoma) and colonic adenomas of different localizations were measured. The spectra of fluorescence excitation of all types of adenomas as well as adenocarcinoma have two maxima at 260/270 nm and at 330/340 nm. The first maximum is primarily defined by tryptophan and phenylalanin containing peptides, one of them is glucagon. The second maximum is mainly defined by collagen in stroma. Progression of precancer lesions to advanced cancer leads to increase of NADH concentration impacting on the second maximum of spectra. However, spectra of all types of the investigated lesions have peculiarities depending on localization. At odds to the previous data about similarities between distal colon and rectum, our results demonstrate similar spectra for proximal colon and rectum due to some similarities in morphological and, as a consequence, biochemical composition. Tumor can be detected by spectral techniques on histological slides even if the specimen contains very few tumorous cells in stroma. Biochemical changes and their similarities for precancer lesions and advanced colon cancer have described. Peculiarities of spectral data for different parts of colon may change the previous opinion about similar mechanisms of cancerogenesis for distal colon and rectum. Moreover, investigation of tissue specimen obtained for histological examination and containing lack of malignant epithelial cells in massive stroma does not interfere with analysis due to specific disproportion of spectrum maxima. Lasers Surg. Med. 49:763-766, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

SU-F-T-505: A Novel Approach for Sparing Critical Organs at Risk for Cancer Patients Undergoing Radiation Oncology Treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lavvafi, H; Pourriahi, M; Elahinia, H

2016-06-15

Purpose: A major goal of an effective radiation treatment plan is to deliver the maximum dose to the tumor while minimizing radiation exposure to the surrounding normal structures. For example, due to the radiation exposure to neighboring critical structures during prostate cancer treatment, a significant increase in cancer risk was observed for the bladder (77%) and the rectum (105%) over the following decade. Consequently, an effective treatment plan necessitates limiting the exposure to such organs which can best be achieved by physically displacing the organ at-risk. The goal of this study is to present a prototype for an organ re-positionermore » device designed and fabricated to physically move the rectum away from the path of radiation beam during external beam and brachytherapy treatments. This device affords patient comfort and provides a fully controlled motion to safely relocate the rectum during treatment. Methods: The NiTi shape memory alloy was designed and optimized for manufacturing a rectal re-positioner device through cooling and heating the core alloy for its shaping. This has been achieved through a prototyped custom designed electronic circuit in order to induce the reversible austenitic transformation and was tested rigorously to ensure the integrity of the actuated motion in displacement of the target anatomy. Results: The desirable NiTi shape-setting was configured for easy insertion and based on anatomical constraint. When the final prototype was evaluated, accuracy and precision of the maximum displacement and temperature changes revealed that the device could safely be used within the target anatomy. Conclusion: The organ re-positioner device is a promising tool that can be implemented in clinical setting. It provides a controlled and safe displacement of the delicate organ(s) at risk. The location of the organ being treated could also be identified using conventional onboard imaging devices or MV imaging available on-board most modern clinical accelerators.« less

Intrafraction Prostate Translations and Rotations During Hypofractionated Robotic Radiation Surgery: Dosimetric Impact of Correction Strategies and Margins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Water, Steven van de, E-mail: s.vandewater@erasmusmc.nl; Valli, Lorella; Alma Mater Studiorum, Department of Physics and Astronomy, Bologna University, Bologna

Purpose: To investigate the dosimetric impact of intrafraction prostate motion and the effect of robot correction strategies for hypofractionated CyberKnife treatments with a simultaneously integrated boost. Methods and Materials: A total of 548 real-time prostate motion tracks from 17 patients were available for dosimetric simulations of CyberKnife treatments, in which various correction strategies were included. Fixed time intervals between imaging/correction (15, 60, 180, and 360 seconds) were simulated, as well as adaptive timing (ie, the time interval reduced from 60 to 15 seconds in case prostate motion exceeded 3 mm or 2° in consecutive images). The simulated extent of robot corrections was alsomore » varied: no corrections, translational corrections only, and translational corrections combined with rotational corrections up to 5°, 10°, and perfect rotational correction. The correction strategies were evaluated for treatment plans with a 0-mm or 3-mm margin around the clinical target volume (CTV). We recorded CTV coverage (V{sub 100%}) and dose-volume parameters of the peripheral zone (boost), rectum, bladder, and urethra. Results: Planned dose parameters were increasingly preserved with larger extents of robot corrections. A time interval between corrections of 60 to 180 seconds provided optimal preservation of CTV coverage. To achieve 98% CTV coverage in 98% of the treatments, translational and rotational corrections up to 10° were required for the 0-mm margin plans, whereas translational and rotational corrections up to 5° were required for the 3-mm margin plans. Rectum and bladder were spared considerably better in the 0-mm margin plans. Adaptive timing did not improve delivered dose. Conclusions: Intrafraction prostate motion substantially affected the delivered dose but was compensated for effectively by robot corrections using a time interval of 60 to 180 seconds. A 0-mm margin required larger extents of additional rotational corrections than a 3-mm margin but resulted in lower doses to rectum and bladder.« less

SU-F-J-84: Comparison of Quantitative Deformable Image Registration Evaluation Tools: Application to Prostate IGART

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dogan, N; Weiss, E; Sleeman, W

Purpose: Errors in displacement vector fields (DVFs) generated by Deformable Image Registration (DIR) algorithms can give rise to significant uncertainties in contour propagation and dose accumulation in Image-Guided Adaptive Radiotherapy (IGART). The purpose of this work is to assess the accuracy of two DIR algorithms using a variety of quality metrics for prostate IGART. Methods: Pelvic CT images were selected from an anonymized database of nineteen prostate patients who underwent 8–12 serial scans during radiotherapy. Prostate, bladder, and rectum were contoured on 34 image-sets for three patients by the same physician. The planning CT was deformably-registered to daily CT usingmore » three variants of the Small deformation Inverse Consistent Linear Elastic (SICLE) algorithm: Grayscale-driven (G), Contour-driven (C, which utilizes segmented structures to drive DIR), combined (G+C); and also grayscale ITK demons (Gd). The accuracy of G, C, G+C SICLE and Gd registrations were evaluated using a new metric Edge Gradient Distance to Agreement (EGDTA) and other commonly-used metrics such as Pearson Correlation Coefficient (PCC), Dice Similarity Index (DSI) and Hausdorff Distance (HD). Results: C and G+C demonstrated much better performance at organ boundaries, revealing the lowest HD and highest DSI, in prostate, bladder and rectum. G+C demonstrated the lowest mean EGDTA (1.14 mm), which corresponds to highest registration quality, compared to G and C DVFs (1.16 and 2.34 mm). However, demons DIR showed the best overall performance, revealing lowest EGDTA (0.73 mm) and highest PCC (0.85). Conclusion: As expected, both C- and C+G SICLE more accurately reproduce manually-contoured target datasets than G-SICLE or Gd using HD and DSI metrics. In general, the Gd appears to have difficulty reproducing large daily position and shape changes in the rectum and bladder. However, Gd outperforms SICLE in terms of EGDTA and PCC metrics, possibly at the expense of topological quality of the estimated DVFs.« less

Comparison of dose volume parameters evaluated using three forward planning – optimization techniques in cervical cancer brachytherapy involving two applicators

PubMed Central

Basu-Roy, Somapriya; Kar, Sanjay Kumar; Das, Sounik; Lahiri, Annesha

2017-01-01

Purpose This study is intended to compare dose-volume parameters evaluated using different forward planning- optimization techniques, involving two applicator systems in intracavitary brachytherapy for cervical cancer. It looks for the best applicator-optimization combination to fulfill recommended dose-volume objectives in different high-dose-rate (HDR) fractionation schedules. Material and methods We used tandem-ring and Fletcher-style tandem-ovoid applicator in same patients in two fractions of brachytherapy. Six plans were generated for each patient utilizing 3 forward optimization techniques for each applicator used: equal dwell weight/times (‘no optimization’), ‘manual dwell weight/times’, and ‘graphical’. Plans were normalized to left point A and dose of 8 Gy was prescribed. Dose volume and dose point parameters were compared. Results Without graphical optimization, maximum width and thickness of volume enclosed by 100% isodose line, dose to 90%, and 100% of clinical target volume (CTV); minimum, maximum, median, and average dose to both rectum and bladder are significantly higher with Fletcher applicator. Even if it is done, dose to both points B, minimum dose to CTV, and treatment time; dose to 2 cc (D2cc) rectum and rectal point etc.; D2cc, minimum, maximum, median, and average dose to sigmoid colon; D2cc of bladder remain significantly higher with this applicator. Dose to bladder point is similar (p > 0.05) between two applicators, after all optimization techniques. Conclusions Fletcher applicator generates higher dose to both CTV and organs at risk (2 cc volumes) after all optimization techniques. Dose restriction to rectum is possible using graphical optimization only during selected HDR fractionation schedules. Bladder always receives dose higher than recommended, and 2 cc sigmoid colon always gets permissible dose. Contrarily, graphical optimization with ring applicators fulfills all dose volume objectives in all HDR fractionations practiced. PMID:29204164

Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy.

PubMed

McDonald, Andrew M; Baker, Christopher B; Popple, Richard A; Shekar, Kiran; Yang, Eddy S; Jacob, Rojymon; Cardan, Rex; Kim, Robert Y; Fiveash, John B

2014-06-03

To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V70 > 3 cc was associated with an increased risk of late GI events. Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients.

Different rectal toxicity tolerance with and without simultaneous conventionally-fractionated pelvic lymph node treatment in patients receiving hypofractionated prostate radiotherapy

PubMed Central

2014-01-01

Purpose To investigate added morbidity associated with the addition of pelvic elective nodal irradiation (ENI) to hypofractionated radiotherapy to the prostate. Methods and materials Two-hundred twelve patients, treated with hypofractionated radiotherapy to the prostate between 2004 and 2011, met the inclusion criteria for the analysis. All patients received 70 Gy to the prostate delivered over 28 fractions and 103 (49%) received ENI consisting of 50.4 Gy to the pelvic lymphatics delivered simultaneously in 1.8 Gy fractions. The mean dose-volume histograms were compared between the two subgroups defined by use of ENI, and various dose-volume parameters were analyzed for effect on late lower gastrointestinal (GI) and genitourinary (GU) toxicity. Results Acute grade 2 lower GI toxicity occurred in 38 (37%) patients receiving ENI versus 19 (17%) in those who did not (p = 0.001). The Kaplan-Meier estimate of grade ≥ 2 lower GI toxicity at 3 years was 15.3% for patients receiving ENI versus 5.3% for those who did not (p = 0.026). Each rectal isodose volume was increased for patients receiving ENI up to 50 Gy (p ≤ 0.021 for each 5 Gy increment). Across all patients, the absolute V70 of the rectum was the only predictor of late GI toxicity. When subgroups, defined by the use of ENI, were analyzed separately, rectal V70 was only predictive of late GI toxicity for patients who received ENI. For patients receiving ENI, V70 > 3 cc was associated with an increased risk of late GI events. Conclusions Elective nodal irradiation increases the rates of acute and late GI toxicity when delivered simultaneously with hypofractioanted prostate radiotherapy. The use of ENI appears to sensitize the rectum to hot spots, therefore we recommend added caution to minimize the volume of rectum receiving 100% of the prescription dose in these patients. PMID:24893842

Dosimetric and radiobiological consequences of computed tomography-guided adaptive strategies for intensity modulated radiation therapy of the prostate.

PubMed

Battista, Jerry J; Johnson, Carol; Turnbull, David; Kempe, Jeff; Bzdusek, Karl; Van Dyk, Jacob; Bauman, Glenn

2013-12-01

To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dose-volume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D95, tumor control probability, V70Gy, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. The CTV D95 for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D95 values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D95 values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V(70Gy) and NTCP) remained within acceptable limits. The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (<5 mm) to an adaptive CTV determined 1 week into therapy minimizes the need for subsequent dose replanning. Copyright © 2013 Elsevier Inc. All rights reserved.

Automatically-generated rectal dose constraints in intensity-modulated radiation therapy for prostate cancer

NASA Astrophysics Data System (ADS)

Hwang, Taejin; Kim, Yong Nam; Kim, Soo Kon; Kang, Sei-Kwon; Cheong, Kwang-Ho; Park, Soah; Yoon, Jai-Woong; Han, Taejin; Kim, Haeyoung; Lee, Meyeon; Kim, Kyoung-Joo; Bae, Hoonsik; Suh, Tae-Suk

2015-06-01

The dose constraint during prostate intensity-modulated radiation therapy (IMRT) optimization should be patient-specific for better rectum sparing. The aims of this study are to suggest a novel method for automatically generating a patient-specific dose constraint by using an experience-based dose volume histogram (DVH) of the rectum and to evaluate the potential of such a dose constraint qualitatively. The normal tissue complication probabilities (NTCPs) of the rectum with respect to V %ratio in our study were divided into three groups, where V %ratio was defined as the percent ratio of the rectal volume overlapping the planning target volume (PTV) to the rectal volume: (1) the rectal NTCPs in the previous study (clinical data), (2) those statistically generated by using the standard normal distribution (calculated data), and (3) those generated by combining the calculated data and the clinical data (mixed data). In the calculated data, a random number whose mean value was on the fitted curve described in the clinical data and whose standard deviation was 1% was generated by using the `randn' function in the MATLAB program and was used. For each group, we validated whether the probability density function (PDF) of the rectal NTCP could be automatically generated with the density estimation method by using a Gaussian kernel. The results revealed that the rectal NTCP probability increased in proportion to V %ratio , that the predictive rectal NTCP was patient-specific, and that the starting point of IMRT optimization for the given patient might be different. The PDF of the rectal NTCP was obtained automatically for each group except that the smoothness of the probability distribution increased with increasing number of data and with increasing window width. We showed that during the prostate IMRT optimization, the patient-specific dose constraints could be automatically generated and that our method could reduce the IMRT optimization time as well as maintain the IMRT plan quality.

Squamous-cell Carcinoma of the Anus and Anal Canal: An Analysis of 55 Cases

PubMed Central

Gabriel, W. B.

1941-01-01

The analysis is of 55 cases admitted into St. Mark's Hospital from 1922 to 1940. The incidence was 3.35% of all cases of cancer of the rectum, anal canal and anus admitted during this period. Sex distribution—27 males and 28 females. The average age (61.7 years) is higher than that of columnar-cell carcinoma of the rectum (57.4 years). Histology.—The cases have been graded into three grades of malignancy—low grade, medium grade, and high grade. Low grade squamous carcinoma is twice as frequent in men as in women, and generally originates at the anal margin. Medium grade squamous carcinoma is equally distributed between men and women; it may arise at the anus or in the anal canal. High grade squamous carcinoma is much more common in the female sex and is almost entirely limited to the anal canal. Quadrant affected—about one-third of the anal margin growths and one-half of the anal canal growths were situated anteriorly. Differential diagnosis from simple papilloma, simple ulcer, chronic inflammation, tuberculous ulcer, tuberculide, primary chancre, amœbic ulcer, basal-cell carcinoma, columnar-cell carcinoma. Biopsy and grading essential before treatment is decided upon. The results of treatment in the three grades of malignancy are described. The best results were obtained in the early low-grade cases treated by interstitial radium needling. In the medium and high grades only three five-year survivals can be reported and these followed excision of the rectum. The management of the inguinal glands is discussed and the importance of a very close post-operative supervision emphasized. Squamous carcinoma of the anal canal may cause lymphatic metastases in the superior hæmorrhoidal glands; there have been four such cases in this series. Diathermy perineal excision is indicated in these cases. ImagesFig. 1Fig. 2Fig. 3Fig. 5Fig. 6aFig. 6bFig. 7Fig. 1Fig. 2Fig. 3Fig. 4 PMID:19992316

Data integrity systems for organ contours in radiation therapy planning.

PubMed

Shah, Veeraj P; Lakshminarayanan, Pranav; Moore, Joseph; Tran, Phuoc T; Quon, Harry; Deville, Curtiland; McNutt, Todd R

2018-06-12

The purpose of this research is to develop effective data integrity models for contoured anatomy in a radiotherapy workflow for both real-time and retrospective analysis. Within this study, two classes of contour integrity models were developed: data driven models and contiguousness models. The data driven models aim to highlight contours which deviate from a gross set of contours from similar disease sites and encompass the following regions of interest (ROI): bladder, femoral heads, spinal cord, and rectum. The contiguousness models, which individually analyze the geometry of contours to detect possible errors, are applied across many different ROI's and are divided into two metrics: Extent and Region Growing over volume. After analysis, we found that 70% of detected bladder contours were verified as suspicious. The spinal cord and rectum models verified that 73% and 80% of contours were suspicious respectively. The contiguousness models were the most accurate models and the Region Growing model was the most accurate submodel. 100% of the detected noncontiguous contours were verified as suspicious, but in the cases of spinal cord, femoral heads, bladder, and rectum, the Region Growing model detected additional two to five suspicious contours that the Extent model failed to detect. When conducting a blind review to detect false negatives, it was found that all the data driven models failed to detect all suspicious contours. The Region Growing contiguousness model produced zero false negatives in all regions of interest other than prostate. With regards to runtime, the contiguousness via extent model took an average of 0.2 s per contour. On the other hand, the region growing method had a longer runtime which was dependent on the number of voxels in the contour. Both contiguousness models have potential for real-time use in clinical radiotherapy while the data driven models are better suited for retrospective use. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Spatial dynamics of the bacterial community structure in the gastrointestinal tract of red kangaroo (Macropus rufus).

PubMed

Li, Meirong; Jin, Wei; Li, Yuanfei; Zhao, Lingling; Cheng, Yanfen; Zhu, Weiyun

2016-06-01

The quantification and community of bacteria in the gastrointestinal (GI) tract (stomach, jejunum, ileum, cecum, colon and rectum) of red kangaroos (Macropus rufus) were examined by using real-time PCR and paired-end Illumina sequencing. The quantification of bacteria showed that the number of bacteria in jejunum and rectum was significantly lower than that in colon and cecum (P < 0.05). A total of 1,872,590 sequences was remained after quality-filtering and 50,948 OTUs were identified at the 97 % similarity level. The dominant phyla in the GI tract of red kangaroos were identified as Actinobacteria, Bacteroidetes and Firmicutes. At the level of genus, the samples from different parts of GI tract clustered into three groups: stomach, small intestine (jejunum and ileum) and large intestine (cecum and rectum). Prevotella (29.81 %) was the most dominant genus in the stomach and significantly (P < 0.05) higher than that in other parts of GI tract. In the small intestine, Bifidobacterium (33.04, 12.14 %) and Streptococcus (22.90, 19.16 %) were dominant genera. Unclassified Ruminococcaceae was the most dominant family in large intestine and the total relative abundance of unclassified bacteria was above 50 %. In identified genera, Dorea was the most important variable to discriminate large intestine and it was significantly higher in cecum than in stomach, small intestine and colon (P < 0.05). Bifidobacterium (21.89 %) was the only dominant genus in colon. Future work on culture in vitro and genome sequencing of those unidentified bacteria might give us insight into the function of these microorganisms in the GI tract. In addition, the comparison of the bacterial community in the foregut of kangaroos and other herbivores and the rumen might give us insight into the mechanism of fiber degradation and help us exploit approaches to improve the feed efficiency and subsequently, reduce the methane emission from herbivores.

Cancer Mortality Following Radiotherapy for Benign Gynecologic Disorders

PubMed Central

Sakata, Ritsu; Kleinerman, Ruth A.; Mabuchi, Kiyohiko; Stovall, Marilyn; Smith, Susan A.; Weathers, Rita; Wactawski-Wende, Jean; Cookfair, Diane L.; Boice, John D.; Inskip, Peter D.

2012-01-01

The purpose of this study is to quantify cancer mortality in relationship to organ-specific radiation dose among women irradiated for benign gynecologic disorders. Included in this study are 12,955 women treated for benign gynecologic disorders at hospitals in the Northeastern U.S. between 1925 and 1965; 9,770 women treated by radiation and 3,186 women treated by other methods. The average age at treatment was 45.9 years (range, 13–88 years), and the average follow-up period was 30.1 years (maximum, 69.9 years). Radiation doses to organs and active bone marrow were reconstructed by medical physicists using original radiotherapy records. The highest doses were received by the uterine cervix (median, 120 Gy) and uterine corpus (median, 34 Gy), followed by the bladder, rectum and colon (median, 1.7–7.2 Gy), with other abdominal organs receiving median doses ≤1 Gy and organs in the chest and head receiving doses <0.1 Gy. Standardized mortality rate ratios relative to the general U.S. population were calculated. Radiation-related risks were estimated in internal analyses using Poisson regression models. Mortality was significantly elevated among irradiated women for cancers of the uterine corpus, ovary, bladder, rectum, colon and brain, as well as for leukemia (exclusive of chronic lymphocytic leukemia) but not for cancer of the cervix, Hodgkin or non-Hodgkin lymphoma, multiple myeloma, or chronic lymphocytic leukemia. Evidence of a dose-response was seen for cancers of the ovary [excess relative risk (ERR) 0.31/Gy, P < 0.001], bladder (ERR = 0.21/Gy, P = 0.02) and rectum (ERR = 0.23/Gy, P = 0.05) and suggested for colon (ERR = 0.09/Gy, P = 0.10), but not for cancers of the uterine corpus or brain nor for non-chronic lymphocytic leukemia. Relative risks of mortality due to cancers of the stomach, pancreas, liver and kidney were close to 1.0, with no evidence of dose-response over the range of 0–1.5 Gy. Breast cancer was not significantly associated with dose to the breast or ovary. Mortality due to cancers of heavily irradiated organs remained elevated up to 40 years after irradiation. Significantly elevated radiation-related risk was seen for cancers of organs proximal to the radiation source or fields (bladder, rectum and ovary), as well as for non-chronic lymphocytic leukemia. Our results corroborate those from previous studies that suggest that cells of the uterine cervix and lymphopoietic system are relatively resistant to the carcinogenic effects of radiation. Studies of women irradiated for benign gynecologic disorders, together with studies of women treated with higher doses of radiation for uterine cancers, provide quantitative information on cancer risks associated with a broad range of pelvic radiation exposures. PMID:22856888

2D radially compensating excitation pulse in combination with an internal transceiver antenna for 3D MRI of the rectum at 7 T.

PubMed

van Kalleveen, I M L; Kroeze, H; Sbrizzi, A; Boer, V O; Reerink, O; Philippens, M E P; van de Berg, C A T; Luijten, P R; Klomp, D W J

2016-07-01

The high precession frequency in ultrahigh field MRI coincides with reduced RF penetration, increased RF power deposition and consequently can lead to reduced scan efficiency. However, the shorter wavelength enables the use of efficient antennas rather than loop coils. In fact, ultrathin monopole antennas have been demonstrated at 7 T, which fit in natural cavities like the rectum in the human body. As the RF field generated by the antenna provides an extremely nonuniform B1 field, the use of conventional RF pulses will lead to severe image distortions and highly nonuniform contrast. However, using the two predominant dimensions (orthogonal to the antenna), 2D RF pulses can be designed that counteract the nonuniform B1 into uniform flip angles. In this study the authors investigate the use of an ultrathin antenna not only for reception, but also for transmission in 7 T MRI of the rectum. The 2D radially compensating excitation (2D RACE) pulse was designed in matlab. SAR calculations between the 2D RACE pulse and an adiabatic RF pulse (BIR-4) have been obtained, to visualize the gain in decreasing the SAR when using the 2D RACE pulse instead of an adiabatic RF pulse. The authors used the 7 T whole body MR system in combination with an internally placed monopole antenna used for transceiving and obtained 3D gradient echo images with a conventional sinc pulse and with the 2D RACE pulse. For extra clarity, they also reconstructed an image where the receive field of the antenna was removed. Comparing the results of the SAR simulations of the 2D RACE pulse with a BIR-4 pulse shows that for low flip angles (θ < 41°) the SAR can be decreased with a factor of 4.8 or even more, when using the 2D RACE pulse. Relative to a conventional sinc excitation, the 2D RACE pulse achieves more uniform flip angle distributions than a BIR-4 pulse with a smaller SAR increase (16 × versus 64 ×). The authors have shown that the 2D RACE pulse provides more homogeneous flip angles for gradient echo sequences when compared to a conventional sinc pulse albeit at increased SAR. However, when compared to adiabatic RF pulses, as shown by simulations, the SAR of the 2D RACE pulse can be an order of magnitude less. Phantom and in vivo human rectum images are obtained to demonstrate that the 2D RACE pulse can provide a uniform excitation while transmitting with a single ultrathin endorectal antenna at 7 T. The combination of thin rectal antennas with efficient uniform transmit can open up new possibilities in high resolution imaging of rectal cancer.

Comparisons of Wartime and Peacetime Disease and Non-Battle Injury Rates Aboard Ships of the British Royal Navy

DTIC Science & Technology

1991-06-01

Kenya Cleopatra Maur itius Enterprise Sirius Kenya Sussex Mauritius Orion Penelope Si rius Sus sex Detors Aligt1ion Ledbury Anthony Liddesdale Beaufurt...Diseases of the Rectum and Anus Diseases of the Liver Other Digestive Diseases DISEASES OF NUTRITION OR METABOLISM Scurvy Beri-Beri Gout Diabetes

Radiotherapy Assessments During Intervention ANd Treatment (RADIANT)

ClinicalTrials.gov

2017-05-02

Radiation Therapy; Cancer; Cancer of Anus; Cancer of Bladder; Cancer of Cervix; Cancer of Colon; Cancer of Rectum; Cancer of Esophagus; Cancer of Gallbladder; Cancer of Liver; Cancer of Ovary; Cancer of Pancreas; Cancer of Prostate; Cancer of Kidney and Renal Pelvis; Cancer of Stomach; Cancer of Testis; Cancer of Uterus; Cancer of Uterus and Cervix; Cancer of Kidney

[Gonorrheal proctitis imitating proctalgia fugax].

PubMed

Nechvátal, A; Masek, T; Hoch, J; Hercogová, J

2004-01-01

Proctalgia fugax is usually a source of many diagnostic and therapeutic problems. It is often very difficult to find the cause of the pain. Case-report of a 27-year-old patient who was examined by surgeons on cramp-like pain localized to the rectum. The careful history and laboratory examination confirmed gonorrheal proctitis. She was then successfully treated with ceftriaxon.

Human Rehabilitation Techniques. Disability Analyses: Chronic Disease Disabilities. Volume II, Part C.

ERIC Educational Resources Information Center

Sigelman, C.; And Others

Volume II, Section C of a six-volume final report (which covers the findings of a research project on policy and technology related to rehabilitation of disabled individuals) presents a review of literature on six types of chronic disease disabilities--rheumatoid arthritis, coronary heart disease, emphysema, carcinoma of the colon/rectum, kidney…

[Vulvovaginitis in young girls].

PubMed

Olejek, Anita; Kellas-Sleczka, Sylwia; Kozak-Darmas, Iwona; Bilska, Anna; Zamłyński, Jacek; Horak, Stanisław; Nowak, Leszek

2009-12-01

Vulvovaginitis is the most common cause of gynecological complaints in young girls. Factors which cause vulvovaginitis include, among other things, low level of sexual hormones (hypoestrogenism), the anatomical proximity of the rectum and delicate vulvar skin and vaginal mucosa. Usually vulvovaginitis in young girls is caused by non-specific factors. The aim of the study was to present the most frequent causes of vulvovaginitis in young girls.

Gastrointestinal Drugs in Aircrew

DTIC Science & Technology

2001-06-01

to the esophageal reflux disease. Am Fam Physician rectum or distal sigmoid, and show clinical 1995;1;52(3):957-62, 965-6. remission without any...prokinetic agent such as cisapride or are: gastroesophageal reflux ; peptic ulcer, both metoclopramide is not, because of serious gastric and duodenal...8217 remitting/relapsing natural history and can be associated with serious complications, such as Gastroesophageal Reflux (GER) hemorrhage and perforation

21 CFR 201.325 - Over-the-counter drugs for vaginal contraceptive and spermicide use containing nonoxynol 9 as the...

Code of Federal Regulations, 2010 CFR

2010-04-01

... from the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome... the rectum. These effects may increase the risk of transmission of the AIDS virus (HIV) from an... transmission of the AIDS virus (HIV) or other STDs, that use of these products can increase vaginal and rectal...

21 CFR 201.325 - Over-the-counter drugs for vaginal contraceptive and spermicide use containing nonoxynol 9 as the...

Code of Federal Regulations, 2013 CFR

2013-04-01

... from the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome... the rectum. These effects may increase the risk of transmission of the AIDS virus (HIV) from an... transmission of the AIDS virus (HIV) or other STDs, that use of these products can increase vaginal and rectal...

21 CFR 201.325 - Over-the-counter drugs for vaginal contraceptive and spermicide use containing nonoxynol 9 as the...

Code of Federal Regulations, 2014 CFR

2014-04-01

... from the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome... the rectum. These effects may increase the risk of transmission of the AIDS virus (HIV) from an... transmission of the AIDS virus (HIV) or other STDs, that use of these products can increase vaginal and rectal...

21 CFR 201.325 - Over-the-counter drugs for vaginal contraceptive and spermicide use containing nonoxynol 9 as the...

Code of Federal Regulations, 2012 CFR

2012-04-01

... from the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome... the rectum. These effects may increase the risk of transmission of the AIDS virus (HIV) from an... transmission of the AIDS virus (HIV) or other STDs, that use of these products can increase vaginal and rectal...

21 CFR 201.325 - Over-the-counter drugs for vaginal contraceptive and spermicide use containing nonoxynol 9 as the...

Code of Federal Regulations, 2011 CFR

2011-04-01

... from the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome... the rectum. These effects may increase the risk of transmission of the AIDS virus (HIV) from an... transmission of the AIDS virus (HIV) or other STDs, that use of these products can increase vaginal and rectal...

Anopenile urethral fistula.

PubMed

Ohno, Koichi; Nakamura, Tetsuro; Azuma, Takashi; Yoshida, Tatsuyuki; Yamada, Hiroto; Hayashi, Hiroaki; Masahata, Kazunori

2008-04-01

A newborn male weighing 3,650 g was born without an anal opening and a perineal fistula. However, an invertography showed rectal gas below the ischium. At the age of 1 day, the patient underwent colostomy. Based on colonourethrography that revealed a fistula between the rectum and the spongy urethra, the patient was diagnosed with an anopenile urethral fistula (APUF). At the age of 7 months, the patient underwent anterior sagittal anorectoplasty (ASARP). The sphincter muscles were divided at the midline. After ligating the fistula, the rectum was pulled through to the anal dimple. At the age of 11 months, a colostomy closure was performed. Consequently, the fistula in the corpus spongiosum penis was not removed. It has been 14 years since the operation was performed, and the patient has had no problems with regard to urination and defecation. According to the embryological studies of the anorectum, APUF could occur due to the following reasons: incomplete descent of the urorectal septum, failed disappearance of the dorsal cloacal membrane, and excessive elongation of the urorectal septum in the phallus. The ASARP provides a superior operative field to identify the fistula and the sphincter muscles. Complete removal of the fistula in the corpus spongiosum penis is unnecessary.

Immunohistochemical observations of methionine-enkephalin and delta opioid receptor in the digestive system of Octopus ocellatus.

PubMed

Sha, Ailong; Sun, Hushan; Wang, Yiyan

2013-02-01

The study was designed to determine whether methionine-enkephalin (met-Enk) or delta opioid receptor was present in the digestive system of Octopus ocellatus. The results showed that they were both in the bulbus oris, esophagus, crop, stomach, gastric cecum, intestine, posterior salivary glands of O. ocellatus, one of them, met-Enk in the rectum, anterior salivary glands, digestive gland. And the distributions were extensive in the digestive system. Strong or general met-Enk immunoreactivity was observed in the inner epithelial cells of the bulbus oris, esophagus, stomach, gastric cecum, intestine, anterior salivary glands and the adventitia of the intestine and rectum, and so was the delta opioid receptor immunoreactivity in the inner epithelial cells of the bulbus oris, esophagus, and crop, however, they were weak in other parts. Combining with delta opioid receptor, met-Enk may be involved in the regulations of food intake, absorption, movement of gastrointestinal smooth muscle and secretion of digestive gland. The different densities of met-Enk and delta opioid receptor may be related to the different functions in the digestive system of O. ocellatus. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rectal bleeding in patients with haemorrhoids. Coincidental findings in colon and rectum.

PubMed

Koning, M V; Loffeld, R J L F

2010-06-01

Rectal bleeding is a very common clinical sign. It is often caused by haemorrhoids. However, it can be a symptom of other pathology in the rectum or colon. There are little data coincidental pathology in patients with haemorrhoids and rectal bleeding. To examine coincidental pathology in patients with rectal bleeding and haemorrhoids, especially with respect to age. Prospectively, 290 consecutive patients presenting with bleeding and haemorrhoids were analysed. All patients had an endoscopic examination. All significant endoscopic findings (diverticuli, polyps, cancer, angiodysplasia and varices or colitis) were recorded. The patients were divided into two groups. Group 1 consisted of patients with only haemorrhoids (n = 129, % male: 41.1, mean age: 53.6 +/- 12.7 years). Group 2 consisted of patients with haemorrhoids and coincidental pathology (n = 161, % male: 46.6, mean age: 67.3 +/- 13.7 years). There was no difference in gender or in the type of endoscopy. However, patients in Group 2 were significantly older. It can be concluded that in cases of rectal bleeding and haemorrhoids, coincidental pathology occurs in a large proportion of patients, especially the elderly. Omitting endoscopy in these patients can lead to major doctors delay.

Comment on ‘Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study’

NASA Astrophysics Data System (ADS)

Valdes, Gilmer; Interian, Yannet

2018-03-01

The application of machine learning (ML) presents tremendous opportunities for the field of oncology, thus we read ‘Deep convolutional neural network with transfer learning for rectum toxicity prediction in cervical cancer radiotherapy: a feasibility study’ with great interest. In this article, the authors used state of the art techniques: a pre-trained convolutional neural network (VGG-16 CNN), transfer learning, data augmentation, drop out and early stopping, all of which are directly responsible for the success and the excitement that these algorithms have created in other fields. We believe that the use of these techniques can offer tremendous opportunities in the field of Medical Physics and as such we would like to praise the authors for their pioneering application to the field of Radiation Oncology. That being said, given that the field of Medical Physics has unique characteristics that differentiate us from those fields where these techniques have been applied successfully, we would like to raise some points for future discussion and follow up studies that could help the community understand the limitations and nuances of deep learning techniques.

An in vivo investigative protocol for HDR prostate brachytherapy using urethral and rectal thermoluminescence dosimetry.

PubMed

Toye, Warren; Das, Ram; Kron, Tomas; Franich, Rick; Johnston, Peter; Duchesne, Gillian

2009-05-01

To develop an in vivo dosimetry based investigative action level relevant for a corrective protocol for HDR brachytherapy boost treatment. The dose delivered to points within the urethra and rectum was measured using TLD in vivo dosimetry in 56 patients. Comparisons between the urethral and rectal measurements and TPS calculations showed differences, which are related to the relative position of the implant and TLD trains, and allowed shifts of implant position relative to the prostate to be estimated. Analysis of rectal dose measurements is consistent with implant movement, which was previously only identified with the urethral data. Shift corrected doses were compared with results from the TPS. Comparison of peak doses to the urethra and rectum has been assessed against the proposed corrective protocol to limit overdosing these critical structures. An initial investigative level of 20% difference between measured and TPS peak dose was established, which corresponds to 1/3 of patients which was practical for the caseload. These patients were assessed resulting in corrective action being applied for one patient. Multiple triggering for selective investigative action is outlined. The use of a single in vivo measurement in the first fraction optimizes patient benefit at acceptable cost.

[Pseudocontinent perineal colostomy].

PubMed

Berrada, S; Khaiz, D; Alloubi, I

2005-01-01

This prospective study was designed to evaluate functional results of a pseudocontinent perineal colostomy (PCPC) using Schmidt's technique. Functional results in eight patients whose rectum were resected due to cancer or anal epidermoid carcinoma and reconstructed by PCPC between January 1995 and July 2002 in our institution were evaluated. Surgical technique and post-operative care were described. Morbidity, functional results and degree of patient satisfaction were reported. Median follow-up was 40 months (18-70 months) and was completed in 100% of patients. There were no operative deaths. Four patients had post-operative complications, whose two patients had partial disunion of sutures, and two patients had urinary infection that was treated by adequate antibiotherapy. No conversion to a definitive abdominal colostomy was performed. On a functional level, one patient has normal continence, six had gas incontinence, and one has occasional minimal soiling. Seventy-five percent of patients were either highly satisfied with their continence. PCPC is a reliable technique, which can be proposed as an alternative to a left iliac colostomy following amputation of the rectum due to cancer, provided that certain requirements are met: careful selection of patients, informed consent, flawless surgical technique and lifetime daily colic irrigation.

Pseudocontinent perineal colostomy following abdominoperineal resection: technique and findings in 49 patients.

PubMed

Lasser, P; Dubé, P; Guillot, J M; Elias, D

2001-02-01

This prospective study was designed to evaluate functional results following the creation of a pseudocontinent perineal colostomy (PCPC) using Schmidt's technique. Functional results in 40 patients whose rectum was resected due to cancer and reconstructed by PCPC between 1989 and 1995 in our institution were evaluated. Anatomical and pathological features of cancers, surgical technique and post-operative care are described. Morbidity, functional results and degree of patient satisfaction are reported. Median follow-up was 45 months (18--87 months) and was completed in 100% of patients. There were no operative deaths. Twenty patients had post-operative complications and two patients had an early conversion to a definitive abdominal colostomy due to serious perineal complications. On a functional level, four patients had normal continence, 23 had gas incontinence, nine had occasional minimal soiling and two had incontinence requiring iliac colostomy. Eighty-six per cent of patients were either highly satisfied or satisfied with their continence. PCPC is a reliable technique that can be suggested as an alternative to a left iliac colostomy following amputation of the rectum due to cancer, provided that certain requirements are met: careful selection of patients, informed consent, flawless surgical technique and lifetime daily colic irrigation. Copyright Harcourt Publishers Limited.

[Pseudo-continent perineal colostomy. Results and techniques].

PubMed

Lasser, P; Dubé, P; Guillot, J M; Elias, D

1997-09-01

This prospective study was conducted to assess functional results obtained after pseudo-continent perineal colostomy using the Schmidt procedure. Functional outcome was assessed in 40 patients who had undergone amputation of the rectum for cancer and pseudo-continent perineal colostomy reconstruction between 1989 and 1995 in our institution. The cancer pathology, operative procedure and post-operative care were noted. Morbidity, functional outcome and degree of patient satisfaction were recorded. Mean follow-up was 45 months (18-87) in 100% of the patients. There were no operative deaths. Twenty patients had post-operative complications and 2 patients required early conversion to definitive abdominal colostomy due to severe perineal complications. Function outcome showed normal continence in 4 patients, air incontinence in 23, occasional minimal leakage in 9 and incontinence requiring iliac colostomy in 2. Eighty-six percent of the patients were highly satisfied or satisfied with their continence capacity. Pseudo-continent perineal colostomy is a reliable technique which can be proposed as an alternative to left iliac colostomy after amputation of the rectum for cancer if a rigorous procedure is applied: careful patient selection, informed consent, rigorous surgical procedure, daily life-long irrigation of the colon.

Multispectral Mueller polarimetric imaging detecting residual cancer and cancer regression after neoadjuvant treatment for colorectal carcinomas

NASA Astrophysics Data System (ADS)

Pierangelo, Angelo; Manhas, Sandeep; Benali, Abdelali; Fallet, Clément; Totobenazara, Jean-Laurent; Antonelli, Maria-Rosaria; Novikova, Tatiana; Gayet, Brice; De Martino, Antonello; Validire, Pierre

2013-04-01

This work is devoted to a first exploration of Mueller polarimetric imaging for the detection of residual cancer after neoadjuvant treatment for the rectum. Three samples of colorectal carcinomas treated by radiochemotherapy together with one untreated sample are analyzed ex vivo before fixation in formalin by using a multispectral Mueller polarimetric imaging system operated from 500 to 700 nm. The Mueller images, analyzed using the Lu-Chipmann decomposition, show negligible diattenuation and retardation. The nonirradiated rectum exhibits a variation of depolarization with cancer evolution stage. At all wavelengths on irradiated samples, the contrast between the footprint of the initial tumor and surrounding healthy tissue is found to be much smaller for complete tumor regression than when a residual tumor is present, even at volume fractions of the order of 5%. This high sensitivity is attributed to the modification of stromal collagen induced by the cancer. The depolarization contrast between treated cancer and healthy tissue is found to increase monotonously with the volume fraction of residual cancer in the red part of the spectrum. Polarimetric imaging is a promising technique for detecting short-time small residual cancers, which is valuable information for pathological diagnosis and patient management by clinicians.

Intestinal stoma in patients with colorectal cancer from the perspective of 20-year period of clinical observation

PubMed Central

Banaszkiewicz, Zbigniew; Woda, Łukasz P.; Tojek, Krzysztof; Jarmocik, Paweł; Jawień, Arkadiusz

2015-01-01

Introduction Intestinal stoma is a procedure most often performed in patients with colorectal cancer. Aim To identify the percentage of patients with colorectal cancer in which the intestinal stoma was performed. Material and methods We retrospectively analysed 443 patients treated during a 20-year period (1994–2013) due to colorectal cancer, in which the intestinal stoma was made during the first surgical intervention. Results In the second analysed decade, a significant decrease in the percentage of created stomas, definitive stomas in particular, was observed. Stomas were made significantly more often in patients with a tumour located in the rectum, the left half of the colon, and in patients undergoing urgent surgeries. An increased incidence of intestinal stomas was associated with a higher severity of illness and higher proportion of unresectable and non-radical procedures. The definitive stomas were significantly more often made in men and in patients with tumours located in the rectum, whereas temporary stomas were created significantly more often in patients undergoing urgent operations. Conclusions In the last decade (2004–2013) the number of intestinal stomas in patients operated due to colorectal cancer was significantly reduced. PMID:25960811

Economic evaluation of pregnancy diagnosis in dairy cattle: a decision analysis approach.

PubMed

Oltenacu, P A; Ferguson, J D; Lednor, A J

1990-10-01

Cost-benefit evaluations of several pregnancy diagnosis schemes were performed. The strategy using on-farm milk progesterone test on d 19 after service, followed by treatment of nonpregnant cows with prostaglandin, was the most profitable returning $10.50 per cow above the cost of the intervention. An increase in efficiency of detection of estrus of greater than 20% among cows diagnosed nonpregnant and an error rate in pregnancy diagnosis of less than or equal to 3% were needed to ensure profitability. Pregnancy diagnosis by uterine palpation per rectum on d 35 after service, combined with the use of pressure-sensitive mounting devices on nonpregnant cows was the second most profitable strategy and returned $5.10 per cow. An increase in efficiency of detection of estrus of greater than or equal to 20% was required to ensure profitability. Embryonic mortality was also critical and an increase from a baseline value of 10% to 12%, as a result of early uterine palpation, made this scheme unprofitable ($-4.80 per cow). Pregnancy diagnosis by uterine palpation per rectum at 50 or 65 d was less profitable, with a return of $2.50 and $.10 per cow, respectively.

[Physiology of the urethral sphincteric vesico-prostatic complex].

PubMed

Carmignani, L; Gadda, F; Dell'Orto, P; Ferruti, M; Grisotto, M; Rocco, F

2001-09-01

We propose a review of the literature about innervation and physiology of the urethral sphincteric complex. Parasympathetic innervation of the pelvic viscera comes from ventral branches of the sacral nerves (S2-S4). The orthosympathetic component derives from superior hypogastric plexus and runs down the hypogastric nerves to form the right and left pelvic plexus together with the parasympathetic component. The pelvic plexus is situated inferolaterally with respect to the rectum and runs on the surface of the levator ani muscle down to the prostatic apex. The pelvic plexus gives innervation to the rectum, the bladder, the prostate and the urethral sphincteric complex. The pelvic muscular floor is innervated by the somatic component (pudendal nerve) derived from the sacral branches (S2-S4). Bladder neck and smooth muscle urethral sphincter innervation is given mostly by the orthosympathetic component. The rhabdosphincter innervation comes from the pudendal nerve and from the pelvic plexus; its role in the continence mechanism is probably to give steady tonic urethral compression. Levator ani muscle takes part in the sphincteric complex with its anteromedial pubococcygeal portion. It plays its role strengthening the sphincteric tone during increase of the abdominal pressure or during active quick stop cessation of the urinary stream.

Management of penetrating extraperitoneal rectal injuries: An Eastern Association for the Surgery of Trauma practice management guideline.

PubMed

Bosarge, Patrick L; Como, John J; Fox, Nicole; Falck-Ytter, Yngve; Haut, Elliott R; Dorion, Heath A; Patel, Nimitt J; Rushing, Amy; Raff, Lauren A; McDonald, Amy A; Robinson, Bryce R H; McGwin, Gerald; Gonzalez, Richard P

2016-03-01

The management of penetrating rectal trauma invokes a complex decision tree that advocates the principles of proximal diversion (diversion) of the fecal stream, irrigation of stool from the distal rectum, and presacral drainage based on data from World War II and the Vietnam War. This guideline seeks to define the initial operative management principles for nondestructive extraperitoneal rectal injuries. A systematic review of the MEDLINE database using PubMed was performed. The search retrieved English language articles regarding penetrating rectal trauma from January 1900 to July 2014. Letters to the editor, case reports, book chapters, and review articles were excluded. Topics of investigation included the management principles of diversion, irrigation of stool from the distal rectum, and presacral drainage using the GRADE methodology. A total of 306 articles were screened leading to a full-text review of 56 articles. Eighteen articles were used to formulate the recommendations of this guideline. This guideline consists of three conditional evidence-based recommendations. First, we conditionally recommend proximal diversion for management of these injuries. Second, we conditionally recommend the avoidance of routine presacral drains and distal rectal washout in the management of these injuries.

Biological effective dose evaluation in gynaecological brachytherapy: LDR and HDR treatments, dependence on radiobiological parameters, and treatment optimisation.

PubMed

Bianchi, C; Botta, F; Conte, L; Vanoli, P; Cerizza, L

2008-10-01

This study was undertaken to compare the biological efficacy of different high-dose-rate (HDR) and low-dose-rate (LDR) treatments of gynaecological lesions, to identify the causes of possible nonuniformity and to optimise treatment through customised calculation. The study considered 110 patients treated between 2001 and 2006 with external beam radiation therapy and/or brachytherapy with either LDR (afterloader Selectron, (137)Cs) or HDR (afterloader microSelectron Classic, (192)Ir). The treatments were compared in terms of biologically effective dose (BED) to the tumour and to the rectum (linear-quadratic model) by using statistical tests for comparisons between independent samples. The difference between the two treatments was statistically significant in one case only. However, within each technique, we identified considerable nonuniformity in therapeutic efficacy due to differences in fractionation schemes and overall treatment time. To solve this problem, we created a Microsoft Excel spreadsheet allowing calculation of the optimal treatment for each patient: best efficacy (BED(tumour)) without exceeding toxicity threshold (BED(rectum)). The efficacy of a treatment may vary as a result of several factors. Customised radiobiological evaluation is a useful adjunct to clinical evaluation in planning equivalent treatments that satisfy all dosimetric constraints.

A case study for online plan adaptation using helical tomotherapy

PubMed Central

Neilson, Christopher E.; Yartsev, Slav

2012-01-01

Helical tomotherapy's ability to provide daily megavoltage (MV) computed tomography (CT) images for patient set-up verification allows for the creation of adapted plans. As plans become more complex by introducing sharper dose gradients in an effort to spare healthy tissue, inter-fraction changes of organ position with respect to plan become a limiting factor in the correct dose delivery to the target. Tomotherapy's planned adaptive option provides the possibility to evaluate the dose distribution for each fraction and subsequently adapt the original plan to the current anatomy. In this study, 30 adapted plans were created using new contours based on the daily MVCT studies of a bladder cancer patient with considerable anatomical variations. Dose to the rectum and two planning target volumes (PTVs) were compared between the original plan, the dose that was actually delivered to the patient, and the theoretical dose from the 30 adapted plans. The adaptation simulation displayed a lower dose to 35% and 50% of the rectum compared to no adaptation at all, while maintaining an equivalent dose to the PTVs. Although online adaptation is currently too time-consuming, it has the potential to improve the effectiveness of radiotherapy. PMID:22557799

Preoperative radiotherapy followed by radical vulvectomy with inguinal lymphadenectomy for advanced vulvar carcinomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rotmensch, J.; Rubin, S.J.; Sutton, H.G.

1990-02-01

A therapeutic alternative to exenteration for large locally advanced vulvar carcinoma involving the rectum, anus, or vagina is the use of preoperative radiation followed by radical surgery. Between 1980 and 1988, 13 patients with Stage III and 3 with Stage IV vulvar carcinoma involving the rectum/anus, urethra, or vagina were treated with 4000 rad to the vulva and 4500 rad to the inguinal and pelvic nodes followed by a radical vulvectomy and inguinal lymphadenectomy 4 weeks later. The overall 5 year cumulative survival was 45%. Twelve tumors regressed after radiation with 62.5% of the patients having visceral preservation while inmore » 4 patients there was no major response to radiation and urinary or fecal diversion was required. Of the 6 recurrences 4 were central and 2 distant. Three patients with central recurrences had tumor within 1 cm of the vulvectomy margin. Complications included wet desquamation, inguinal wound separation, lymphedema, and urethral strictures. There were no operative deaths. It is concluded that the use of preoperative radiation followed by radical vulvectomy may be an alternative to pelvic exenteration in selected patients with advanced vulvar lesions.« less

Magnetic resonance imaging of the female pelvis: initial experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hricak, H.; Alpers, C.; Crooks, L.E.

1983-12-01

The potential of magnetic resonance imaging (MRI) was evaluated in 21 female subjects: seven volunteers, 12 patients scanned for reasons unrelated to the lower genitourinary tract, and two patients referred with gynecologic disease. The uterus at several stages was examined; the premenarcheal uterus (one patient), the uterus of reproductive age (12 patients), the postmenopausal uterus (two patients), and in an 8 week pregnancy (one patient). The myometrium and cyclic endometrium in the reproductive age separated by a low-intensity line (probably stratum basale), which allows recognition of changes in thickness of the cyclic endometrium during the menstrual cycle. The corpus uterimore » can be distinguished from the cervix by the transitional zone of the isthmus. The anatomic relation of the uterus to bladder and rectum is easily outlined. The vagina can be distinguished from the cervix, and the anatomic display of the closely apposed bladder, vagina, and rectum is clear on axial and coronal images. The ovary is identified; the signal intensity from the ovary depends on the acquisition parameter used. Uterine leiomyoma, endometriosis, and dermoid cyst were depicted, but further experience is needed to ascertain the specificity of the findings.« less

Effects of a 3 strain -based direct-fed microbial and dietary fiber concentration on growth performance and expression of genes related to absorption and metabolism of volatile fatty acids in weanling pigs.

PubMed

Jaworski, N W; Owusu-Asiedu, A; Walsh, M C; McCann, J C; Loor, J J; Stein, H H

2017-01-01

Effects of a -based direct-fed microbial (DFM) on growth performance, plasma tumor necrosis factor ɑ (TNFɑ), relative gene expression, and intestinal VFA concentrations in weanling pigs fed low- or high-fiber diets were evaluated. Two hundred pigs (initial BW: 6.31 ± 0.73 kg) were allotted to 1 of 4 dietary treatments (5 pigs per pen and 10 pens per treatment). Treatments were arranged in a 2 × 2 factorial design with 2 diet types [low-fiber (LF) or high-fiber (HF)] and 2 concentrations of DFM (0 or 60 g DFM/t of feed). The DFM contained 1.5 × 10 cfu/g and was obtained from Danisco Animal Nutrition-DuPont Industrial Biosciences, Marlborough, UK. Phase 1 diets were fed for 2 wk post-weaning and phase 2 diets were fed over the following 29 d. Low fiber diets contained corn and soybean meal as main ingredients and HF diets contained corn, soybean meal, corn distillers dried grains with solubles (7.5 and 15.0% in phase 1 and 2, respectively), and wheat middlings (10.0%). Pigs and feed were weighed at the start and at the end of each phase, and ADG, ADFI, and G:F were calculated. At the conclusion of phase 2, blood was collected from 1 pig per pen and 1 pig per pen was sacrificed. Cecum and rectum contents were analyzed for VFA, and tissue samples were collected from the ileum, cecum, rectum, and liver to determine expression of genes related to absorption and metabolism of VFA using quantitative reverse transcription-PCR. Results indicated that feeding HF diets reduced ( ≤ 0.05) ADFI and ADG of pigs compared with feeding LF diets. Pigs fed DFM diets had improved ( ≤ 0.05) G:F compared with pigs fed non-DFM diets. Pigs fed LF diets had greater ( ≤ 0.05) BW at the end of phase 2 compared with pigs fed HF diets. The concentration of VFA in rectum contents was greater ( ≤ 0.05) in pigs fed LF diets than in pigs fed HF diets. The expression of in the rectum of pigs fed HF diets was greater ( ≤ 0.05) than for pigs fed LF diets, and pigs fed DFM-containing diets had an increased ( ≤ 0.05) expression of in the liver. Pigs fed HF diets had greater ( ≤ 0.05) concentrations of urea N in plasma compared with pigs fed LF diets, but dietary fiber and DFM had no effect on plasma concentration of TNF-ɑ. In conclusion, the -based DFM improved overall G:F of weanling pigs, but pigs fed LF diets had greater final BW than pigs fed HF diets.

Inhibiting NANOG Enhances Efficacy of BH3 Mimetics | Center for Cancer Research

Cancer.gov

BCL-2 family proteins regulate cell fate. Some members promote cell survival while others induce programmed cell death. A third group, the BH3-only members, modulates the activities of the rest of the family. Some cancers, including those of the colon and rectum, express elevated levels of pro-survival BCL-2 members, which may protect cancer cells from chemotherapy. BH3

Occipital condyle syndrome secondary to bone metastases from rectal cancer.

PubMed

Marruecos, J; Conill, C; Valduvieco, I; Vargas, M; Berenguer, J; Maurel, J

2008-01-01

Skull-base metastases are very unfrequent. Occipital condyle syndrome (OCS) is usually underdiagnosed. Until now few cases have been reported in the literature. We present a 71-year-old woman with metastatic rectum adenocarcinoma, with right occipital headache and ipsilateral hypoglossal palsy, diagnosed by computed tomography and magnetic resonance imaging of OCS due to a skull-base metastasis and treated with radiation therapy.

[The role of whole body 2-[fluorine-18]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in the management of unknown primary tumors].

PubMed

Wu, Zhi-Jian; Zhang, Yong-Xue; Wei, Hao; Jia, Qing

2007-08-28

To assess the role of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) in the management of unknown primary primary (CUP) with metastatic loci. Thirty-four patients of CUP with metastatic loci who had undergone unsuccessful conventional diagnostic work-up underwent (18)F-FDG PET/CT. The images thus obtained were analyzed with visual and semi-quantitative methods. Histopathology, cytology, and/or follow-up were used to evaluate the PET/CT results. In 20 of the 34 patients (18)F-FDG PET/CT showed focal tracer accumulations corresponding to potential primary tumor sites located in the lung (n = 9), colon (n = 3), rectum (n = 2), pancreas (n = 1), right aryepiglottic wall (n = 1), esophagus (n = 1), breast (n = 1), and ovary (n = 2). The detection rate of primary tumor by (18)F-FDG PET/CT was 50.0% (17/34), the primary tumors were identified in the lung (n = 8), colon (n = 2), rectum (n = 1), pancreas (n = 1), right aryepiglottic wall (n = 1), esophagus (n = 1), ovary (n = 2), and breast (n = 1). The false positive rate was 8.8% (3/34) with the diagnosis of primary tumor in the lung (n = 1), colon (n = 1), and rectum (n = 1) to be identified as false. In 14 of the 34 patients, (18)F-FDG PET/CT did not reveal lesions suspected to be the primary tumor sites in 13 patients, and it was impossible to identify one lesion as the most likely primary tumor in one patient due to the presence of multiple hot spots in several organs. The (18)F-FDG PET/CT findings affected the medical management in 17 of the 34 (50.0%) patients due to the finding of primary sites and/or additional metastases. (18)F-FDG PET/CT has relevant impact on the therapeutic management of patients with unknown primary tumor. It is recommended that (18)F-FDG PET/CT be performed in the patient with unknown primary tumor after unsuccessful conventional diagnostic workup.

Concordance of gonorrhoea of the rectum, pharynx and urethra in same-sex male partnerships attending a sexual health service in Melbourne, Australia.

PubMed

Cornelisse, Vincent J; Zhang, Lei; Law, Matthew; Chen, Marcus Y; Bradshaw, Catriona S; Bellhouse, Clare; Fairley, Christopher K; Chow, Eric P F

2018-02-27

We aimed to describe anatomic site-specific concordance of gonococcal infections in partnerships of men who have sex with men (MSM). We conducted a cross-sectional analysis of data from MSM partnerships attending Melbourne Sexual Health Centre between March 2011 and February 2015. Logistic regression models (random effect) were used to examine the association between gonococcal infections of the urethra, rectum and pharynx. Gonococci were detected by culture at all anatomic sites. The analysis included 495 partnerships. Of the men with urethral gonorrhoea, 33% (95% CI 18-52) had partners with pharyngeal gonorrhoea and 67% (95% CI 48-82) had partners with rectal gonorrhoea. The adjusted odds of having urethral gonorrhoea was 4.6 (95% CI 1.2-17.1) for a man whose partner had pharyngeal gonorrhoea, and 48.1 (95% CI 18.3-126.7) for a man whose partner had rectal gonorrhoea. Of the men with rectal gonorrhoea, 46% (95% CI 31-61) had a partner with urethral gonorrhoea and 23% (95% CI 12-37) had a partner with pharyngeal gonorrhoea. The adjusted odds of having rectal gonorrhoea was 63.9 (95% CI 24.7-165.6) for a man whose partner had urethral gonorrhoea. Of the men with pharyngeal gonorrhoea, 42% (95% CI 23-63) had a partner with rectal gonorrhoea and 23% (95% CI 9-44) had a partner with had a partner with pharyngeal gonorrhoea. The adjusted odds of having pharyngeal gonorrhoea was 8.9 (95% CI 3.2-24.6) for a man whose partner had rectal gonorrhoea. The crude odds of having pharyngeal gonorrhoea was 14.2 (95% CI 5.1-39.0) for a man whose partner had pharyngeal gonorrhoea. These data provide the first estimates of concordance of anatomic site-specific gonococcal infections in MSM partnerships, and confirm that urethral gonorrhoea is contracted from both rectal and pharyngeal sites, and suggest that gonococci transmit between the rectum and pharynx. However, due to use of culture rather than NAAT, our analysis was not adequately powered to assess pharynx-to-pharynx transmission of gonococci.

First clinical implementation of the Capri applicator

PubMed Central

2014-01-01

This study was to assess the Capri applicator for patients with endometrial cancer undergoing high‐radiation dose treatments following external‐beam radiation therapy. The Capri applicator is an inflatable vaginal cylinder with multiple channels. It is used to tailor the dose distribution to an asymmetric vaginal disease, and better spare organs at risk. Five patients with high‐risk endometrial cancer were selected for this study. The patients were treated with a high dose of radiation using the Capri applicator: daily fraction of 7 Gy was prescribed for a total dose of 21 Gy. The treatment plans included radiobiological parameters such as equivalent uniform dose (EUD), normal tissue complication probability (NTCP), and tumor control probability (TCP). Based on the dose‐volume histograms (DVH), we also calculated four quality factors: conformity index (CI), dose homogeneity index (DHI), dose nonuniformity index (DNR), and overdose index (OI). The TCP values range from 82.26% to 95.92%. Very low values of NTCP were observed for the bladder and rectum. The EUDs to organs at risk ranged from 4.65 Gy to 18.22 Gy for the bladder, and from 3.41 Gy from to 6.56 Gy for the rectum. The mean CI was 1.05(SD=0.0008). The mean DNR was 0.10(range0.0−0.295,SD=0.100). The mean OI was 0.019(SD=0.028). The DHIs were in the range of 1.0−0.754(mean0.886,SD=0.116). The use of a multichannel vaginal cylinder may not only help cover extensive vaginal disease, but also reduce the dose to the rectum. This dosimetric analysis shows that rectal doses could be reduced using a multichannel cylinder. However, the dose delivered to the bladder based on EUD calculation may be higher than that obtained with other methods. Each patient must be evaluated independently to determine if a multichannel treatment is appropriate. Clinical followup will show whether this rectal dose sparing translates into a real toxicity improvement. PACS number: 3.6.96.0 PMID:24423857