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Sample records for iodine-125 prostate brachytherapy

  1. Influence of Dose on Risk of Acute Urinary Retention After Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Roeloffzen, Ellen M.A.; Battermann, Jan J.; Deursen, Marijke J.H. van; Monninkhof, Evelyn M.; Visscher, Mareije I.; Moerland, Marinus A.; Vulpen, Marco van

    2011-07-15

    Purpose: To assess the influence of dose on the risk of acute urinary retention (AUR) after iodine-125 prostate brachytherapy. Methods and Materials: Between January 2005 and December 2008, 714 consecutive patients with localized prostate cancer were treated with iodine-125 prostate brachytherapy at our department. All patients completed four imaging studies: magnetic resonance imaging before and 4 weeks after treatment and intraoperative three-dimensional transrectal ultrasonography before and after implantation. The development of AUR was prospectively recorded. The evaluated treatment and dosimetric parameters included prostate volume, number of needles and seeds used, intra- and postoperative prostate edema, percentage of prostate volume receiving 100%, 150%, and 200% of the prescribed dose to the prostate, minimal dose received by 90% of the prostate volume, and percentage of the urethra receiving 100%, 150%, and 200% of the prescribed dose. Logistic regression analysis was used to examine which factors were associated with AUR. Results: Of the 714 patients, 57 (8.0%) developed AUR. On univariate analysis, the following treatment and dosimetric factors were significantly associated with AUR: International Prostate Symptom Score (odds ratio [OR], 2.07, per 10-point increase), preimplant prostate volume (OR, 1.06), postimplant prostate volume (OR, 1.04), number of needles used (OR, 1.09), and number of seeds used (OR, 1.03). On multivariate analysis, the only independent predictive factors for AUR were pretreatment prostate volume (OR, 1.05) and International Prostate Symptom Score (OR, 1.76, per 10-point increase). Patients with a pretreatment prostate volume >35 cm{sup 3} had a 10.4% risk of developing AUR compared with 5.4% for those with a prostate volume of {<=}35 cm{sup 3}. No association was found between any of the dosimetric parameters and the development of AUR. Conclusion: The radiation dose, within the range studied, did not influence the risk of AUR

  2. Complications associated with preoperative radiation therapy and Iodine-125 brachytherapy for localized prostatic carcinoma

    SciTech Connect

    Flanigan, R.C.; Patterson, J.; Mendiondo, O.A.; Gee, W.F.; Lucas, B.A.; McRoberts, J.W.

    1983-08-01

    Twenty-five consecutive patients with localized adenocarcinoma of the prostate treated with 1,050 rad preoperative radiation therapy and Iodine-125 seed brachytherapy are reviewed. Significant long-term postoperative complications included radiation cystitis (12%), radiation proctitis (4%), genital and leg edema (12%), stress incontinence (8%), total incontinence (4%), and impotence (26%). Complications occurred in 75 per cent of patients who received additional postoperative radiation. Improved staging with CT scan, lymphangiography, and Chiba needle biopsy of any possibly abnormal lymph nodes provided excellent preoperative staging with only 1 patient (6%) upstaged at surgery to Stage D1.

  3. A Phase III Randomized Trial of the Timing of Meloxicam With Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita; Patil, Nikhilesh; Wallace, Kris; Borg, Jette; Zhou, David; Ma, Clement; Pond, Greg

    2010-06-01

    Purpose: Nonsteroidal anti-inflammatory medication is used to reduce prostate edema and urinary symptoms following prostate brachytherapy. We hypothesized that a cyclooxygenase-2 (COX-2) inhibitor regimen started 1 week prior to seed implant might diminish the inflammatory response, thus reducing edema, retention rates, and symptom severity. Methods and Materials: From March 2004 to February 2008, 316 men consented to an institutional review board-approved randomized study of a 4-week course of meloxicam, 7.5 mg orally twice per day, starting either on the day of implant or 1 week prior to implant. Brachytherapy was performed using iodine-125 seeds and was preplanned and performed under transrectal ultrasound (TRUS) and fluoroscopic guidance. Prostate volume obtained by MR imaging at 1 month was compared to baseline prostate volume obtained by TRUS planimetry and expressed as an edema factor. The trial endpoints were prostate edema at 1 month, International Prostate Symptom Score (IPSS) questionnaire results at 1 and 3 months, and any need for catheterization. Results: Results for 300 men were analyzed. Median age was 61 (range, 45-79 years), and median TRUS prostate volume was 35.7 cc (range, 18.1-69.5 cc). Median IPSS at baseline was 5 (range, 0-24) and was 15 at 1 month, 16 at 3 months, and 10 at 6 months. Catheterization was required for 7% of patients (6.2% day 0 arm vs. 7.9% day -7 arm; p = 0.65). The median edema factor at 1 month was 1.02 (range, 0.73-1.7). 1.01 day 0 arm vs. 1.05 day -7 arm. Baseline prostate volume remained the primary predictor of postimplant urinary retention. Conclusions: Starting meloxicam 1 week prior to brachytherapy compared to starting immediately after the procedure did not reduce 1-month edema, improve IPSSs at 1 or 3 months, or reduce the need for catheterization.

  4. Prostate-Specific Antigen Bounce After Permanent Iodine-125 Prostate Brachytherapy-An Australian Analysis

    SciTech Connect

    Zwahlen, Daniel R.; Smith, Ryan; Andrianopoulos, Nick; Matheson, Bronwyn; Royce, Peter; Millar, Jeremy L.

    2011-01-01

    Purpose: To report on prostate-specific antigen (PSA) 'bounces' after {sup 125}I prostate brachytherapy to review the relationship to biochemical control and correlate both clinical and dosimetric variables. Methods and Materials: We analyzed 194 hormone-naive patients with a follow-up of {>=}3 years. Four bounce definitions were applied: an increase of {>=}0.2 ng/mL (definition I), {>=}0.4 ng/mL (definition II), {>=}15% (definition III), and {>=}35% (definition IV) of a previous value with spontaneous return to the prebounce level or lower. Results: Using definition I, II, III, and IV, a bounce was detected in 50%, 34%, 11%, and 9% of patients, respectively. The median time to onset was 14-16 months, the duration was 12-21.5 months, and the magnitude of the increase was 0.5-2 ng/mL. A magnitude of >2 ng/mL, fulfilling the criteria for biochemical failure (BF) according to the American Society for Therapeutic Radiology and Oncology Phoenix definition, was detected in 11.3%, 16.9%, 47.6%, and 50% using definitions I, II, III, and IV, respectively; 11 patients (5.7%) had true BF. The PSA bounces occurred earlier than BF (p < 0.001). The prediction of BF remains controversial and is probably unrelated to biochemical control. The only statistically significant factor predictive of a PSA bounce was younger age (definitions I and II). Conclusion: PSA bounces are common after brachytherapy. All definitions resulted in a high number of false-positive calls for BF during the first 2 years. The definition of an increase of {>=}0.2 ng/mL should be preferred because of the lowest number of false-positive results for BF. Patients experiencing a PSA bounce during the first 2 years after brachytherapy should undergo surveillance every 3-6 months. Additional investigations are recommended for elevated postimplant PSA levels that have not corrected by 3 years of follow-up.

  5. Novel Parameter Predicting Grade 2 Rectal Bleeding After Iodine-125 Prostate Brachytherapy Combined With External Beam Radiation Therapy

    SciTech Connect

    Shiraishi, Yutaka; Hanada, Takashi; Ohashi, Toshio; Yorozu, Atsunori; Toya, Kazuhito; Saito, Shiro; Shigematsu, Naoyuki

    2013-09-01

    Purpose: To propose a novel parameter predicting rectal bleeding on the basis of generalized equivalent uniform doses (gEUD) after {sup 125}I prostate brachytherapy combined with external beam radiation therapy and to assess the predictive value of this parameter. Methods and Materials: To account for differences among radiation treatment modalities and fractionation schedules, rectal dose–volume histograms (DVHs) of 369 patients with localized prostate cancer undergoing combined therapy retrieved from corresponding treatment planning systems were converted to equivalent dose-based DVHs. The gEUDs for the rectum were calculated from these converted DVHs. The total gEUD (gEUD{sub sum}) was determined by a summation of the brachytherapy and external-beam radiation therapy components. Results: Thirty-eight patients (10.3%) developed grade 2+ rectal bleeding. The grade 2+ rectal bleeding rate increased as the gEUD{sub sum} increased: 2.0% (2 of 102 patients) for <70 Gy, 10.3% (15 of 145 patients) for 70-80 Gy, 15.8% (12 of 76 patients) for 80-90 Gy, and 19.6% (9 of 46 patients) for >90 Gy (P=.002). Multivariate analysis identified age (P=.024) and gEUD{sub sum} (P=.000) as risk factors for grade 2+ rectal bleeding. Conclusions: Our results demonstrate gEUD to be a potential predictive factor for grade 2+ late rectal bleeding after combined therapy for prostate cancer.

  6. Iodine 125 interstitial irradiation for localized prostate cancer.

    PubMed Central

    Kumar, P. P.; Good, R. R.; Bartone, F. F.

    1990-01-01

    We present the technique, complications, and 5-year results of transperineal percutaneous template permanent interstitial iodine 125 endocurietherapy of localized prostate cancer in 85 treated patients. The 5-year outcome appears similar to that of external beam radiation therapy or radical surgery, but the iatrogenic mortality, morbidity, treatment time, and hospitalization are significantly reduced. Images Figure 1 Figure 2 Figure 3 PMID:2319613

  7. Enhancement of high intensity Iodine-125 brachytherapy by cis-platinum in a murine bladder tumor model

    SciTech Connect

    Nag, S.; Blatnik, A.; Soloway, M.

    1984-06-01

    The interaction of cis-platinum chemotherapy and high-intensity Iodine-125 brachytherapy was studied in C3H/He mice with MBT-2 tumors growing in the thigh. Brachytherapy was delivered by 3 Iodine-125 seeds of 10 mCi each implanted into the tumor. Ninety-six animals were randomly divided into 8 groups of 12 animals each. Each group was given either no treatment (control), cis-platinum alone or brachytherapy of 20, 40 or 50 Gy either alone or combined with cis-platinum. Cis-platinum 3 mg. per kg. was given every 5 days for 3 doses. The addition of cis-platinum enhanced the effects of Iodine-125 brachytherapy as shown by the end-points of tumor regrowth delay, local tumor control and median survival times. The sensitization enhancement ratio ranged from 1.2 to 1.9. Further experiments are to be conducted to study the normal tissue effect, therapeutic gain factor, effects of altering the time of administration of cis-platinum and the clinical use of high-intensity Iodine-125 for removable brachytherapy.

  8. Long-term follow-up of patients of intrahepatic malignancies treated with Iodine-125 brachytherapy

    SciTech Connect

    Nag, Subir . E-mail: nag.1@osu.edu; DeHaan, Megan; Scruggs, Granger; Mayr, Nina; Martin, Edward W.

    2006-03-01

    Purpose: We investigated the role of intraoperative iodine-125 ({sup 125}I) brachytherapy as a treatment option for unresectable primary and metastatic liver tumors. Methods and Materials: Between 1989 and 2002, 64 patients with unresectable or residual disease after surgical resection for intrahepatic malignancies underwent 160-Gy permanent {sup 125}I brachytherapy. Results: The median length of follow-up was 13.2 years. The overall 1-year, 3-year, and 5-year actuarial intrahepatic local control rates were 44%, 22%, and 22%, respectively, with a median time to liver recurrence of 9 months (95% CI, 6-12 months). The 5-year actuarial intrahepatic control was higher for patients with solitary metastasis (38%) than for those with multiple metastases (6%, p = 0.04). The 1-year, 3-year, and 5-year actuarial overall survival rates were 73%, 23%, and 5%, respectively (median, 20 months; 95% CI, 16-24; longest survival, 7.5 years). Overall survival was higher for patients with smaller-volume implants (p = 0.003) and for patients without prior liver resection (p = 0.002). No mortality occurred. Radiation-related complications were minimal. Conclusions: For select patients with unresectable primary and metastatic liver tumors for whom curative surgical resection is not an option, {sup 125}I brachytherapy is a safe and effective alternative to other locally ablative techniques and can provide long-term local control and increased survival.

  9. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherap*

    PubMed Central

    Franca, Carlos Antônio da Silva; Vieira, Sérgio Lannes; Carvalho, Antonio Carlos Pires; Bernabe, Antonio Jose Serrano; Penna, Antonio Belmiro Rodrigues Campbell

    2014-01-01

    Objective To evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%), and biochemical recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1 presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19 patients (43.2%) (p < 0.02). The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02), respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence. PMID:25741055

  10. Combination of cryosurgery and Iodine-125 seeds brachytherapy for lung cancer

    PubMed Central

    Zhou, Liang; Xu, Kecheng; Mu, Feng

    2012-01-01

    It has been proven that radioactive seeds such as Iodine-125 seeds implantation is a highly effective treatment for patients with localized cancer, such as lung cancer. It may increase the effectiveness of cryosurgery for lung cancer with the combination of Iodine-125 seed implantation into edge of the cryoablation zone. Percutaneous cryosurgery and Iodine-125 seed implantation are mutual complementation; both have been proved to be safe and effective modality for unresectable lung cancer, especially for centrally located lung cancer. Well-designed, randomized and control study both in the laboratory and in the clinical about this option are needed before the conclusive evidence submits. PMID:23050115

  11. Outcomes of Iodine-125 Plaque Brachytherapy for Uveal Melanoma With Intraoperative Ultrasonography and Supplemental Transpupillary Thermotherapy

    SciTech Connect

    Badiyan, Shahed N.; Rao, Rajesh C.; Apicelli, Anthony J.; Acharya, Sahaja; Verma, Vivek; Garsa, Adam A.; DeWees, Todd; Speirs, Christina K.; Garcia-Ramirez, Jose; Esthappan, Jacqueline; Grigsby, Perry W.; Harbour, J. William

    2014-03-15

    Purpose: To assess the impact on local tumor control of intraoperative ultrasonographic plaque visualization and selective application of transpupillary thermotherapy (TTT) in the treatment of posterior uveal melanoma with iodine-125 (I-125) episcleral plaque brachytherapy (EPB). Methods and Materials: Retrospective analysis of 526 patients treated with I-125 EPB for posterior uveal melanoma. Clinical features, dosimetric parameters, TTT treatments, and local tumor control outcomes were recorded. Statistical analysis was performed using Cox proportional hazards and Kaplan-Meier life table method. Results: The study included 270 men (51%) and 256 women (49%), with a median age of 63 years (mean, 62 years; range, 16-91 years). Median dose to the tumor apex was 94.4 Gy (mean, 97.8; range, 43.9-183.9) and to the tumor base was 257.9 Gy (mean, 275.6; range, 124.2-729.8). Plaque tilt >1 mm away from the sclera at plaque removal was detected in 142 cases (27%). Supplemental TTT was performed in 72 patients (13.7%). One or 2 TTT sessions were required in 71 TTT cases (98.6%). After a median follow-up of 45.9 months (mean, 53.4 months; range, 6-175 months), local tumor recurrence was detected in 19 patients (3.6%). Local tumor recurrence was associated with lower dose to the tumor base (P=.02). Conclusions: Ultrasound-guided plaque localization of I-125 EPB is associated with excellent local tumor control. Detection of plaque tilt by ultrasonography at plaque removal allows supplemental TTT to be used in patients at potentially higher risk for local recurrence while sparing the majority of patients who are at low risk. Most patients require only 1 or 2 TTT sessions.

  12. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    SciTech Connect

    Marathe, Omkar S.; Wu, Jeffrey; Lee, Steve P.; Yu Fei; Burgess, Barry L.; Leu Min; Straatsma, Bradley R.; McCannel, Tara A.

    2011-11-15

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after {sup 125}I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for {sup 125}I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  13. Dosimetric and Late Radiation Toxicity Comparison Between Iodine-125 Brachytherapy and Stereotactic Radiation Therapy for Juxtapapillary Choroidal Melanoma

    SciTech Connect

    Krema, Hatem

    2013-07-01

    Purpose: To compare the dose distributions and late radiation toxicities for {sup 125}I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Methods: Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log–rank test compared the estimates. Results: The median follow-up was 46 months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Conclusions: Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma.

  14. Prostate brachytherapy

    MedlinePlus

    Implant therapy - prostate cancer; Radioactive seed placement; Internal radiation therapy - prostate; High dose radiation (HDR) ... plan and then place the seeds that deliver radiation into your prostate. The seeds are placed with ...

  15. Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

    SciTech Connect

    McCannel, Tara A. McCannel, Colin A.

    2014-06-01

    Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy

  16. Long-Term Results of Brachytherapy With Temporary Iodine-125 Seeds in Children With Low-Grade Gliomas

    SciTech Connect

    Korinthenberg, Rudolf; Neuburger, Daniela; Trippel, Michael; Ostertag, Christoph; Nikkhah, Guido

    2011-03-15

    Purpose: To retrospectively review the results of temporary I-125 brachytherapy in 94 children and adolescents with low-grade glioma. Methods and Materials: Treatment was performed in progressive tumors roughly spherical in shape with a diameter of up to 5 cm, including 79 astrocytomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 1 ependymoma, and 5 other tumors. Location was suprasellar/chiasmal in 44, thalamic/basal ganglia in 18, hemispheric in 15, midbrain/pineal region in 13, and lower brainstem in 3. Initially, 8% of patients were free of symptoms, 47% were symptomatic but not disabled, and 30% were slightly, 6% moderately, and 3% severely disabled. Results: 5- and 10-year survival was 97% and 92%. The response to I-125 brachytherapy over the long term was estimated after a median observation period of 38.4 (range, 6.4-171.0) months. At that time, 4 patients were in complete, 27 in partial, and 18 in objective remission; 15 showed stable and 30 progressive tumors. Treatment results did not correlate with age, sex, histology, tumor size, location, or demarcation of the tumor. Secondary treatment became necessary in 36 patients, including 19 who underwent repeated I-125 brachytherapy. At final follow-up, the number of symptom-free patients had risen to 21%. Thirty-eight percent showed symptoms without functional impairment, 19% were slightly and 11% moderately disabled, and only 4% were severely disabled. Conclusions: Response rates similar to those of conventional radiotherapy or chemotherapy can be anticipated with I-125 brachytherapy in tumors of the appropriate size and shape. We believe it to be a useful contribution to the treatment of low-grade gliomas in children.

  17. Phase I Trial of Gross Total Resection, Permanent Iodine-125 Brachytherapy, and Hyperfractionated Radiotherapy for Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Chen, Allen M.; Chang, Susan; Pouliot, Jean; Sneed, Penny K.; Prados, Michael D.; Lamborn, Kathleen R.; Malec, Mary K.; McDermott, Michael W.; Berger, Mitchell S.; Larson, David A.

    2007-11-01

    Purpose: To evaluate the feasibility of gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy for patients with newly diagnosed glioblastoma. Methods and Materials: From April 1999 to May 2002, 21 patients with glioblastoma multiforme were enrolled on a Phase I protocol investigating planned gross total resection and immediate placement of permanent I-125 seeds, followed by postoperative hyperfractionated radiotherapy to a dose of 60 Gy at 100 cGy b.i.d., 5 days per week. Median age and Karnofsky performance status were 50 years (range, 32-65 years) and 90 (range, 70-100), respectively. Toxicity was assessed according to Radiation Therapy Oncology Group criteria. Results: Eighteen patients completed treatment according to protocol. The median preoperative tumor volume on magnetic resonance imaging was 18.6 cm{sup 3} (range, 4.4-41.2 cm{sup 3}). The median brachytherapy dose measured 5 mm radially outward from the resection cavity was 400 Gy (range, 200-600 Gy). Ten patients underwent 12 reoperations, with 11 of 12 reoperations demonstrating necrosis without evidence of tumor. Because of high toxicity, the study was terminated early. Median progression-free survival and overall survival were 57 and 114 weeks, respectively, but not significantly improved compared with historical patients treated at University of California, San Francisco, with gross total resection and radiotherapy without brachytherapy. Conclusions: Treatment with gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy as performed in this study results in high toxicity and reoperation rates, without demonstrated improvement in survival.

  18. Some theoretical derivations relating to the tissue dosimetry of brachytherapy nuclides, with particular reference to iodine-125

    SciTech Connect

    Dale, R.G.

    1983-03-01

    Using a Monte Carlo computer technique, tables of parameters have been derived which are of use in the dosimetry of brachytherapy nuclides in a variety of tissues and organs. From the results, it has been possible to derive relationships linking the composition of a tissue with the dose received at any location around an implanted source. Other factors, such as the relative importance of scattered radiation, spectral degradation, and integral dose, are also discussed. In particular, attention is drawn to possible dosimetric problems arising from the clinical use of /sup 125/I.

  19. Brachytherapy with Iodine-125 seeds strand for treatment of main portal vein tumor thrombi: an experimental study in a rabbit model

    PubMed Central

    Zhang, Wen; Luo, Jianjun; Liu, Qingxin; Ma, Jingqin; Qu, Xudong; Yang, Minjie; Yan, Zhiping; Wang, Jianhua

    2016-01-01

    This study aims to establish an animal model of implanted main portal vein tumor thrombus (MPVTT) and to evaluate safety and efficacy of brachy therapy with Iodine-125 (125I) seeds strand to treat MPVTT of rabbit. VX2 tumor thrombus was implanted in main portal vein (MPV) of 32 New Zealand white rabbits. These rabbits were randomly divided into treatment group (Group T, T1-T16) and control group (Group C, C1-C16). 125I seeds and blank seeds strand were implanted in MPV of rabbits in Group T and C, respectively. Changes of general condition, body weight and blood laboratory examination were monitored at every time point after procedure. 2 weeks later, 8 rabbits of each group were sacrificed for pathologic examination. The rest of rabbits were dissected postmortem, and therapeutic effects were evaluated on basis of multi-detector computed tomography and histopathology. Ki-67 labeling index (Ki-67 LI) and apoptosis index (AI) were compared between two groups. Overall survival period was recorded. At every time point after brachytherapy, more serious weight loss were detected in Group C. Results of liver function tests and blood cells counts showed no significant difference between two groups. Mean volume of tumor tissue within MPV were 565.40 ± 220.90 mm3 in Group T and 2269.90 ± 437.00 mm3 in Group C (P < 0.001). (Ki-67 LI) and AI were (4.14 ± 1.84)% and (6.51 ± 1.92)% in Group T, compared with (33.82 ± 6.07)% and (0.91 ± 0.26)% in Group C, respectively (P < 0.001). Media survival time of rabbits were 39.50 ± 2.37 days in Group T and 27.38 ± 1.22 days in Group C, respectively (P = 0.001). In conclusion, injecting and suspensory fixing VX2 tumor strip into MPV is a reliable method to establish MPVTT animal model. Brachytherapy with 125I seeds strand was safe and effective to treat VX2 tumor strand inoculated in the MPV of rabbit. PMID:27152237

  20. Dosimetry of a thyroid uptake detected in seed migration survey following a patient's iodine-125 prostate implant and in vitro measurements of intentional seed leakages

    SciTech Connect

    Chen Qinsheng; Russell, John L. Jr.; Macklis, Roger R.; Weinhous, Martin S.; Blair, Henry F.

    2006-07-15

    As a quality control procedure, a post-implant seed migration survey has been accomplished on 340 prostate cancer patients since November 2001. Pulmonary seed embolization and intracardiac seed embolization have been detected. A case of thyroid uptake due to leaking iodine-125 (I-125) sources was also seized. In order to determine the dose to the thyroid, a dosimetry method was developed to link in vivo measurements and the cumulated dose to the thyroid. The calculated source leakage half-life in the case was approximately 15 days based on the measurements and the estimated cumulated dose to thyroid was 204 cGy. It is concluded that one seed was leaking. In order to verify the in vivo measurements, intentional in vitro seed leakage tests were performed. A seed was cut open and placed in a sealed glass container filled with a given volume of saline. The I-125 concentration in the saline was subsequently measured over a period of six months. Consistent in vivo and in vitro results were obtained. Recent incidents of seed leaks reported from other centers have drawn practitioners' attention to this problem. In order to make the measurements more useful, the seed leakage tests were expanded to include I-125 seeds from six other vendors. The results show that the leakage half-lives of those seeds varied from nine days to a half-year. Two seed models demonstrated least leakage. Since the measurements lasted for six months, the escape of iodine resulted from oxidation of iodide in the saline was a concern for the measurement accuracy. As a reference, another set of leakage tests were performed by adding sodium thiosulfate salt (Na{sub 2}S{sub 2}O{sub 3}{center_dot}5H{sub 2}O) to the saline. Sodium thiosulfate is a reducing agent that prevents the conversion of iodide to iodate so as to minimize I-125 evaporation. As a result, significantly shortened leakage half-lives were observed in this group. Seed agitation was also performed and no significant deviations of the

  1. SU-E-T-55: Biological Equivalent Dose (BED) Comparison Between Permanent Interstitial Brachytherapy and Conventional External Beam Radiotherapy for Prostate Cancer

    SciTech Connect

    Liu, X; Rahimian, J; Cosmatos, H; Goy, B; Heywood, C; Qian, Y

    2014-06-01

    Purpose: The goal of this research is to calculate and compare the Biological Equivalent Dose (BED) between permanent prostate Iodine-125 implant brachytherapy as monotherapy with the BED of conventional external beam radiation therapy (EBRT). Methods: A retrospective study of 605 patients treated with Iodine-125 seed implant was performed in which physician A treated 274 patients and physician B treated 331 patients. All the Brachytherapy treatment plans were created using VariSeed 8 planning system. The Iodine-125 seed source activities and loading patterns varied slightly between the two physicians. The prescription dose is 145 Gy to PTV for each patient. The BED and Tumor Control Probability (TCP) were calculated based on the TG 137 formulas. The BED for conventional EBRT of the prostate given in our institution in 2Gy per fraction for 38 fractions was calculated and compared. Results: Physician A treated 274 patients with an average BED of 123.92±0.87 Gy and an average TCP of 99.20%; Physician B treated 331 patients with an average BED of 124.87±1.12 Gy and an average TCP of 99.30%. There are no statistically significant differences (T-Test) between the BED and TCP values calculated for these two group patients.The BED of the patients undergoing conventional EBRT is calculated to be 126.92Gy. The BED of the patients treated with permanent implant brachytherapy and EBRT are comparable. Our BED and TCP values are higher than the reported values by TG 137 due to higher Iodine-125 seed activity used in our institution. Conclusion: We calculated the BED,a surrogate of the biological response to a permanent prostate brachytherapy using TG 137 formulas and recommendation. The TCP of better than 99% is calculated for these patients. A clinical outcome study of these patients correlating the BED and TCP values with PSA and Gleason Levels as well as patient survival is warranted.

  2. Segmental Urethral Dosimetry and Urinary Toxicity in Patients With No Urinary Symptoms Before Permanent Prostate Brachytherapy

    SciTech Connect

    Thomas, Carys; Keyes, Mira Liu, Mitchell; Moravan, Veronika

    2008-10-01

    Purpose: To determine whether segmental urethral dosimetry is predictive for the degree of urinary morbidity after prostate brachytherapy in patients with no urinary symptoms before prostate brachytherapy. Methods and Materials: Between May 2000 and November 2005, 1,107 patients underwent iodine-125 monotherapy with urethral sparing techniques. A total of 166 patients fulfilled the selection criteria: baseline (International Prostate Symptom Score) IPSS {<=}5, no androgen deprivation therapy, and prostate ultrasound planning volumes (PUTV) <45 mL. The median follow-up was 44 months. Urinary morbidity was defined by maximum increase in IPSS, time to IPSS resolution, maximum Radiation Therapy Oncology Group (RTOG) score, time to RTOG resolution, and urinary retention. Surrogate deviated urethra was contoured and doses calculated at the base, mid-prostate, apex, and urogenital diaphragm. Univariate and multivariate analysis was used to evaluate urethral and prostate dosimetry, age, PUTV, and number of needles for their association with urinary morbidity. Results: Urethral dose was fairly constant in all urethra segments except prostate base, where the variation in does was large. On multivariate analysis, higher urethral base D50, V100, and larger PUTV were predictive for higher maximum increase in IPSS. Higher urethral base V100 and larger PUTV predicted for prolonged IPSS resolution. Higher urethral base D50 and larger needle number predicted for longer RTOG resolution. Higher urethral base V100 predicted for RTOG {>=}2 toxicity. Conclusions: Radiation dose to the urethral base, larger PUTV, and needle number, predicted for increased urinary toxicity after prostate brachytherapy. Correlation between urinary morbidity and urethral base dosimetry may reflect a large variation in urethral dose observed at the prostate base.

  3. Pretreatment Nomogram to Predict the Risk of Acute Urinary Retention After I-125 Prostate Brachytherapy

    SciTech Connect

    Roeloffzen, Ellen M.; Vulpen, Marco van; Battermann, Jan J.; Roermund, Joep G. van; Saibishkumar, Elantholi P.; Monninkhof, Evelyn M.

    2011-11-01

    Purpose: Acute urinary retention (AUR) after iodine-125 (I-125) prostate brachytherapy negatively influences long-term quality of life and therefore should be prevented. We aimed to develop a nomogram to preoperatively predict the risk of AUR. Methods: Using the preoperative data of 714 consecutive patients who underwent I-125 prostate brachytherapy between 2005 and 2008 at our department, we modeled the probability of AUR. Multivariate logistic regression analysis was used to assess the predictive ability of a set of pretreatment predictors and the additional value of a new risk factor (the extent of prostate protrusion into the bladder). The performance of the final model was assessed with calibration and discrimination measures. Results: Of the 714 patients, 57 patients (8.0%) developed AUR after implantation. Multivariate analysis showed that the combination of prostate volume, IPSS score, neoadjuvant hormonal treatment and the extent of prostate protrusion contribute to the prediction of AUR. The discriminative value (receiver operator characteristic area, ROC) of the basic model (including prostate volume, International Prostate Symptom Score, and neoadjuvant hormonal treatment) to predict the development of AUR was 0.70. The addition of prostate protrusion significantly increased the discriminative power of the model (ROC 0.82). Calibration of this final model was good. The nomogram showed that among patients with a low sum score (<18 points), the risk of AUR was only 0%-5%. However, in patients with a high sum score (>35 points), the risk of AUR was more than 20%. Conclusion: This nomogram is a useful tool for physicians to predict the risk of AUR after I-125 prostate brachytherapy. The nomogram can aid in individualized treatment decision-making and patient counseling.

  4. 10-Year Experience With I-125 Prostate Brachytherapy at the Princess Margaret Hospital: Results for 1,100 Patients

    SciTech Connect

    Crook, Juanita; Borg, Jette; Evans, Andrew; Toi, Ants; Saibishkumar, E.P.; Fung, Sharon; Ma, Clement

    2011-08-01

    Purpose: To report outcomes for 1,111 men treated with iodine-125 brachytherapy (BT) at a single institution. Methods and Materials: A total of 1,111 men (median age, 63) were treated with iodine-125 prostate BT for low- or intermediate-risk prostate cancer between March 1999 and November 2008. Median prostate-specific antigen (PSA) level was 5.4 ng/ml (range, 0.9-26.1). T stage was T1c in 66% and T2 in 34% of patients. Gleason score was 6 in 90.1% and 7 or 8 in 9.9% of patients. Neoadjuvant hormonal therapy (2-6 months course) was used in 10.1% of patients and combined external radiotherapy (45 Gy) with BT (110 Gy) in 4.1% (n = 46) of patients. Univariate and multivariate Cox proportional hazards were used to determine predictors of failure. Results: Median follow-up was 42 months (range, 6-114), but for biochemical freedom from relapse, a minimum PSA test follow-up of 30 months was required (median 54; n = 776). There were 27 failures, yielding an actuarial 7-year disease-free survival rate of 95.2% (96 at risk beyond 84 months). All failures underwent repeat 12-core transrectal ultrasound -guided biopsies, confirming 8 local failures. On multivariate analysis, Gleason score was the only independent predictor of failure (p = 0.001; hazard ratio, 4.8 (1.9-12.4). Median International Prostate Symptom score from 12 to 108 months ranged between 3 and 9. Of the men reporting baseline potency, 82.8% retained satisfactory erectile function beyond 5 years. Conclusion: Iodine-125 prostate BT is a highly effective treatment option for favorable- and intermediate-risk prostate cancer and is associated with maintenance of good urinary and erectile functions.

  5. Urinary and Rectal Toxicity Profiles After Permanent Iodine-125 Implant Brachytherapy in Japanese Men: Nationwide J-POPS Multi-institutional Prospective Cohort Study

    SciTech Connect

    Ohashi, Toshio; Yorozu, Atsunori; Saito, Shiro; Tanaka, Nobumichi; Katayama, Norihisa; Kojima, Shinsuke; Maruo, Shinichiro; Kikuchi, Takashi; Dokiya, Takushi; Fukushima, Masanori; Yamanaka, Hidetoshi

    2015-09-01

    Purpose: To assess, in a nationwide multi-institutional cohort study begun in 2005 and in which 6927 subjects were enrolled by 2010, the urinary and rectal toxicity profiles of subjects who enrolled during the first 2 years, and evaluate the toxicity profiles for permanent seed implantation (PI) and a combination therapy with PI and external beam radiation therapy (EBRT). Methods and Materials: Baseline data for 2339 subjects out of 2354 patients were available for the analyses. Toxicities were evaluated using the National Cancer Institute's Common Terminology Criteria for Adverse Events, and the International Prostate Symptom Scores were recorded prospectively until 36 months after radiation therapy. Results: Grade 2+ acute urinary toxicities developed in 7.36% (172 of 2337) and grade 2+ acute rectal toxicities developed in 1.03% (24 of 2336) of the patients. Grade 2+ late urinary and rectal toxicities developed in 5.75% (133 of 2312) and 1.86% (43 of 2312) of the patients, respectively. A higher incidence of grade 2+ acute urinary toxicity occurred in the PI group than in the EBRT group (8.49% vs 3.66%; P<.01). Acute rectal toxicity outcomes were similar between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late urinary toxicities were 6.04% versus 4.82% for the PI and the EBRT groups, respectively, with no significant differences between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late rectal toxicities were 0.90% versus 5.01% (P<.01) for the PI and the EBRT groups, respectively. The mean of the postimplant International Prostate Symptom Score peaked at 3 months, but it decreased to a range that was within 2 points of the baseline score, which was observed in 1625 subjects (69.47%) at the 1-year follow-up assessment. Conclusions: The acute urinary toxicities observed were acceptable given the frequency and retention, and the late rectal toxicities were more favorable than those of other studies.

  6. Salvage Brachytherapy for Biochemically Recurrent Prostate Cancer following Primary Brachytherapy

    PubMed Central

    Lacy, John M.; Wilson, William A.; Bole, Raevti; Chen, Li; Meigooni, Ali S.; Rowland, Randall G.; Clair, William H. St.

    2016-01-01

    Purpose. In this study, we evaluated our experience with salvage brachytherapy after discovery of biochemical recurrence after a prior brachytherapy procedure. Methods and Materials. From 2001 through 2012 twenty-one patients treated by brachytherapy within University of Kentucky or from outside centers developed biochemical failure and had no evidence of metastases. Computed tomography (CT) scans were evaluated; patients who had an underseeded portion of their prostate were considered for reimplantation. Results. The majority of the patients in this study (61.9%) were low risk and median presalvage PSA was 3.49 (range 17.41–1.68). Mean follow-up was 61 months. At last follow-up after reseeding, 11/21 (52.4%) were free of biochemical recurrence. There was a trend towards decreased freedom from biochemical recurrence in low risk patients (p = 0.12). International Prostate Symptom Scores (IPSS) increased at 3-month follow-up visits but decreased and were equivalent to baseline scores at 18 months. Conclusions. Salvage brachytherapy after primary brachytherapy is possible; however, in our experience the side-effect profile after the second brachytherapy procedure was higher than after the first brachytherapy procedure. In this cohort of patients we demonstrate that approximately 50% oncologic control, low risk patients appear to have better outcomes than others. PMID:27092279

  7. Autoradiography for iodine-125 seeds

    SciTech Connect

    Alberti, W.; Divoux, S. ); Pothmann, B.; Tabor, P. ); Hermann, K.P.; Harder, D. )

    1993-04-02

    To study the interior design of model 6702 and 6711 iodine-125 seeds, contact autoradiographs were performed using mammography film. Improved resolution was obtained using a pin-hole camera with a hole of 0.1 mm [times] 0.1 mm. With these techniques, qualitative determination of the relative activity distribution within each seed was possible. The number of the activated resin spheres and the positions of the centers of these spheres can be exactly determined. A model calculation shows that variations in the arrangement of the activated spheres within a seed have a moderate influence on the dose distribution at source distances below 10 mm. Knowing the exact source configuration may be useful when comparing dose calculations with measured data for model 6702 [sup 125]I seeds which are currently employed in ophthalmic plaque and implant therapy of other tumors. 16 refs., 5 figs., 2 tabs.

  8. Early voiding dysfunction associated with prostate brachytherapy.

    PubMed

    Wagner; Nag; Young; Bahnson

    2000-12-15

    Introduction: Transperineal prostate brachytherapy is gaining popularity as a treatment for clinically localized carcinoma of the prostate. Very little prospective data exists addressing the issue of complications associated with this procedure. We present an analysis of the early voiding dysfunction associated with prostate brachytherapy. Materials and Methods: Forty-six consecutive patients who underwent Palladium-103 (Pd-103) seed placement for clinically localized prostate carcinoma were evaluated prospectively for any morbidity associated with the procedure. Twenty-three patients completed an International Prostate Symptom Score (IPSS) questionnaire preoperatively, at their first postoperative visit, and at their second postoperative visit. The total IPSS, each of the seven individual components, and the "bother" score were evaluated separately for each visit, and statistical significance was determined. Results: Urinary retention occurred in 7/46 patients (15%). Of these, 5 were able to void spontaneously after catheter removal. One patient is maintained with a suprapubic tube, and one patient is currently on continuous intermittent catheterization. Baseline IPSS was 7.1 and this went to 20.0 at the first postoperative visit (p<0.001). By the second postoperative visit, the IPSS was 8.0. Conclusions: In our experience, prostate brachytherapy for localized carcinoma of the prostate is associated with a 15% catheterization rate and a significant increase in the IPSS (7.1 to 20.0). This increase in the IPSS seems to be self-limited. Patients need to be educated on these issues prior to prostate brachytherapy. PMID:11113369

  9. Photoacoustic imaging of prostate brachytherapy seeds in ex vivo prostate

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Kang, Hyun Jae; DeJournett, Travis; Spicer, James; Boctor, Emad

    2011-03-01

    The localization of brachytherapy seeds in relation to the prostate is a key step in intraoperative treatment planning (ITP) for improving outcomes in prostate cancer patients treated with low dose rate prostate brachytherapy. Transrectal ultrasound (TRUS) has traditionally been the modality of choice to guide the prostate brachytherapy procedure due to its relatively low cost and apparent ease of use. However, TRUS is unable to visualize seeds well, precluding ITP and producing suboptimal results. While other modalities such as X-ray and magnetic resonance imaging have been investigated to localize seeds in relation to the prostate, photoacoustic imaging has become an emerging and promising modality to solve this challenge. Moreover, photoacoustic imaging may be more practical in the clinical setting compared to other methods since it adds little additional equipment to the ultrasound system already adopted in procedure today, reducing cost and simplifying engineering steps. In this paper, we demonstrate the latest efforts of localizing prostate brachytherapy seeds using photoacoustic imaging, including visualization of multiple seeds in actual prostate tissue. Although there are still several challenges to be met before photoacoustic imaging can be used in the operating room, we are pleased to present the current progress in this effort.

  10. Establishing High-Quality Prostate Brachytherapy Using a Phantom Simulator Training Program

    SciTech Connect

    Thaker, Nikhil G.; Kudchadker, Rajat J.; Swanson, David A.; Albert, Jeffrey M.; Bruno, Teresa L.; Prestidge, Bradley R.; Crook, Juanita M.; Cox, Brett W.; Potters, Louis; Moran, Brian J.; Keyes, Mira; Kuban, Deborah A.; Frank, Steven J.

    2014-11-01

    Purpose: To design and implement a unique training program that uses a phantom-based simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education. Methods and Materials: Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 ({sup 125}I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis. Results: Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 >95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees' ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process. Conclusions: Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB.

  11. Automated intraoperative calibration for prostate cancer brachytherapy

    SciTech Connect

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-11-15

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 {+-} 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 {+-} 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 {+-} 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 {+-} 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  12. Erectile Function Durability Following Permanent Prostate Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H.

    2009-11-01

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 >= 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  13. Iodine-125 radiation of posterior uveal melanoma

    SciTech Connect

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  14. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear stuctures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  15. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear structures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  16. A novel perineal shield for low-dose-rate prostate brachytherapy

    PubMed Central

    Schwartz, David; Safdieh, Joseph; Polubarov, Alex; Telivala, Tejas; Worth, Matthew; Schreiber, David

    2015-01-01

    Purpose To study the impact on radiation exposure to staff through the use of an original perineal shield during low-dose-rate prostate brachytherapy. Material and methods We designed a 1 mm thick stainless steel shield that duplicates and is able to slide directly over a standard commercialized prostate brachytherapy grid. We then analyzed the post-procedure exposure in 15 consecutive patients who underwent Iodine-125 seed placement. Measurements were performed with and without the shield in place at fixed locations relative to the grid template. Endpoints were analyzed using the paired two-sample t-test, with statistical significance defined as a p-value < 0.05. Results The exposure at the midline grid template ranged from 0.144-0.768 mSv/hr without the shield, and 0.038-0.144 mSv/hr with the shield (p < 0.0001). The exposure 10 cm left of the grid template was 0.134-0.576 mSv/hr without the shield, and 0.001-0.012 mSv/hr with the shield (p < 0.0001). The exposure 10 cm right of the grid template was 0.125-0.576 mSv/hr without the shield, and 0.001-0.012 mSv/hr with the shield (p < 0.0001). The median reduction of exposure at the grid was 76% midline, 98.5% left, and 99% right. Similarly, each individual dose rate was recorded at 25 cm from the perineum, both with and without shield. The median reduction of exposure 25 cm from the perineum was 73.7% midline, 77.7% left and 81.6% right (p < 0.0001). Conclusions Our novel shield took seconds to install and was non-restrictive during the procedure, and provided at least a four-fold reduction in radiation exposure to the brachytherapist. PMID:26207107

  17. Prostate Brachytherapy With Oblique Needles to Treat Large Glands and Overcome Pubic Arch Interference

    SciTech Connect

    Ryu, Bon; Bax, Jeff; Edirisinge, Chandima; Lewis, Craig; Chen, Jeff; D'Souza, David; Fenster, Aaron; Wong, Eugene

    2012-08-01

    Purpose: First, to show that low-dose-rate prostate brachytherapy plans using oblique needle trajectories are more successful than parallel trajectories for large prostates with pubic arch interference (PAI); second, to test the accuracy of delivering an oblique plan by using a three-dimensional (3D) transrectal ultrasonography (TRUS)-guided mechatronic system. Methods and Materials: Prostates were contoured for 5 subjects' 3D TRUS images showing a maximum PAI of {<=}1 cm and a prostate volume of <50 cc. Two planning studies were done. First, prostate contours were artificially enlarged to 45 to 80 cc in 5- to 10-cc increments for a single subject. Second, all subject prostate contours were enlarged to 60 cc. For each study, three types of plans were manually created for comparison: a parallel needle template (PT) plan, a parallel needle no-template (PNT) plan, and an oblique needle no-template (OBL) plan. Needle positions and angles were not discretized for nontemplate plans. European Society for Therapeutic Radiology and Oncology dose-volume histogram guidelines, iodine-125 (145-Gy prescription, 0.43 U), and needle angles of <15 Degree-Sign were used. An OBL plan was delivered to a pubic arch containing a 60-cc prostate phantom that mimicked the anatomy of the subject with the greatest PAI (23% by volume). Results: In the increasing-prostate volume study, OBL plans were successful for prostates of {<=}80 cc, and PT plans were successful for prostates of <65 cc. In paired, one-sided t tests for the 60-cc volume study, OBL plans showed dosimetric improvements for all organs compared to both of the parallel type plans (p < 0.05); PNT plans showed a benefit only in planning target volumes receiving more than 100 Gy compared to PT plans. A computed tomography scan of the phantom showed submillimeter seed placement accuracy in all directions. Conclusion: OBL plans were significantly better than parallel plans, and an OBL plan was accurately delivered to a 60-cc

  18. A dynamic dosimetry system for prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Dehghan, Ehsan; Deguet, Anton; Song, Danny Y.; Prince, Jerry L.; Lee, Junghoon

    2013-03-01

    The lack of dynamic dosimetry tools for permanent prostate brachytherapy causes otherwise avoidable problems in prostate cancer patient care. The goal of this work is to satisfy this need in a readily adoptable manner. Using the ubiquitous ultrasound scanner and mobile non-isocentric C-arm, we show that dynamic dosimetry is now possible with only the addition of an arbitrarily configured marker-based fiducial. Not only is the system easily configured from accessible hardware, but it is also simple and convenient, requiring little training from technicians. Furthermore, the proposed system is built upon robust algorithms of seed segmentation, fiducial detection, seed reconstruction, and image registration. All individual steps of the pipeline have been thoroughly tested, and the system as a whole has been validated on a study of 25 patients. The system has shown excellent results of accurately computing dose, and does so with minimal manual intervention, therefore showing promise for widespread adoption of dynamic dosimetry.

  19. Fast dose kernel interpolation using Fourier transform with application to permanent prostate brachytherapy dosimetry

    SciTech Connect

    Liu, Derek Sloboda, Ron S.

    2014-05-15

    Purpose: Boyer and Mok proposed a fast calculation method employing the Fourier transform (FT), for which calculation time is independent of the number of seeds but seed placement is restricted to calculation grid points. Here an interpolation method is described enabling unrestricted seed placement while preserving the computational efficiency of the original method. Methods: The Iodine-125 seed dose kernel was sampled and selected values were modified to optimize interpolation accuracy for clinically relevant doses. For each seed, the kernel was shifted to the nearest grid point via convolution with a unit impulse, implemented in the Fourier domain. The remaining fractional shift was performed using a piecewise third-order Lagrange filter. Results: Implementation of the interpolation method greatly improved FT-based dose calculation accuracy. The dose distribution was accurate to within 2% beyond 3 mm from each seed. Isodose contours were indistinguishable from explicit TG-43 calculation. Dose-volume metric errors were negligible. Computation time for the FT interpolation method was essentially the same as Boyer's method. Conclusions: A FT interpolation method for permanent prostate brachytherapy TG-43 dose calculation was developed which expands upon Boyer's original method and enables unrestricted seed placement. The proposed method substantially improves the clinically relevant dose accuracy with negligible additional computation cost, preserving the efficiency of the original method.

  20. Predictors of Metastatic Disease After Prostate Brachytherapy

    SciTech Connect

    Forsythe, Kevin; Burri, Ryan; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To identify predictors of metastatic disease after brachytherapy treatment for prostate cancer. Methods and Materials: All patients who received either brachytherapy alone (implant) or brachytherapy in combination with external beam radiation therapy for treatment of localized prostate cancer at The Mount Sinai Hospital between June 1990 and March 2007 with a minimum follow-up of 2 years were included. Univariate and multivariable analyses were performed on the following variables: risk group, Gleason score (GS), clinical T stage, pretreatment prostate-specific antigen level, post-treatment prostate-specific antigen doubling time (PSA-DT), treatment type (implant vs. implant plus external beam radiation therapy), treatment era, total biological effective dose, use of androgen deprivation therapy, age at diagnosis, and race. PSA-DT was analyzed in the following ordinate groups: 0 to 90 days, 91 to 180 days, 180 to 360 days, and greater than 360 days. Results: We included 1,887 patients in this study. Metastases developed in 47 of these patients. The 10-year freedom from distant metastasis (FFDM) rate for the entire population was 95.1%. Median follow-up was 6 years (range, 2-15 years). The only two significant predictors of metastatic disease by multivariable analyses were GS and PSA-DT (p < 0.001 for both variables). Estimated 10-year FFDM rates for GS of 6 or less, GS of 7, and GS of 8 or greater were 97.9%, 94.3%, and 76.1%, respectively (p < 0.001). Estimated FFDM rates for PSA-DT of 0 to 90 days, 91 to 180 days, 181 to 360 days, and greater than 360 days were 17.5%, 67.9%, 74%, and 94.8%, respectively (p < 0.001). Estimated 10-year FFDM rates for the low-, intermediate-, and high-risk groups were 98.6%, 96.2%, and 86.7%, respectively. A demographic shift to patients presenting with higher-grade disease in more recent years was observed. Conclusions: GS and post-treatment PSA-DT are both statistically significant independent predictors of metastatic

  1. Sexual Function and the Use of Medical Devices or Drugs to Optimize Potency After Prostate Brachytherapy

    SciTech Connect

    Whaley, J. Taylor; Levy, Lawrence B.; Swanson, David A.; Pugh, Thomas J.; Kudchadker, Rajat J.; Bruno, Teresa L.; Frank, Steven J.

    2012-04-01

    Purpose: Prospective evaluation of sexual outcomes after prostate brachytherapy with iodine-125 seeds as monotherapy at a tertiary cancer care center. Methods and Materials: Subjects were 129 men with prostate cancer with I-125 seed implants (prescribed dose, 145 Gy) without supplemental hormonal or external beam radiation therapy. Sexual function, potency, and bother were prospectively assessed at baseline and at 1, 4, 8, and 12 months using validated quality-of-life self-assessment surveys. Postimplant dosimetry values, including dose to 10% of the penile bulb (D10), D20, D33, D50, D75, D90, and penile volume receiving 100% of the prescribed dose (V100) were calculated. Results: At baseline, 56% of patients recorded having optimal erections; at 1 year, 62% of patients with baseline erectile function maintained optimal potency, 58% of whom with medically prescribed sexual aids or drugs. Variables associated with pretreatment-to-posttreatment decline in potency were time after implant (p = 0.04) and age (p = 0.01). Decline in urinary function may have been related to decline in potency. At 1 year, 69% of potent patients younger than 70 years maintained optimal potency, whereas 31% of patients older than 70 maintained optimal potency (p = 0.02). Diabetes was related to a decline in potency (p = 0.05), but neither smoking nor hypertension were. For patients with optimal potency at baseline, mean sexual bother scores had declined significantly at 1 year (p < 0.01). Sexual potency, sexual function, and sexual bother scores failed to correlate with any dosimetric variable tested. Conclusions: Erections firm enough for intercourse can be achieved at 1 year after treatment, but most men will require medical aids to optimize potency. Although younger men were better able to maintain erections firm enough for intercourse than older men, there was no correlation between potency, sexual function, or sexual bother and penile bulb dosimetry.

  2. Evaluation of the MIM Symphony treatment planning system for low-dose-rate- prostate brachytherapy.

    PubMed

    Dhanesar, Sandeep K; Lim, Tze Y; Du, Weiliang; Bruno, Teresa L; Frank, Steven J; Kudchadker, Rajat J

    2015-09-08

    MIM Symphony is a recently introduced low-dose-rate prostate brachytherapy treatment planning system (TPS). We evaluated the dosimetric and planning accuracy of this new TPS compared to the universally used VariSeed TPS. For dosimetric evaluation of the MIM Symphony version 5.4 TPS, we compared dose calculations from the MIM Symphony TPS with the formalism recommended by the American Association of Physicists in Medicine Task Group 43 report (TG-43) and those generated by the VariSeed version 8.0 TPS for iodine-125 (I-125; Models 6711 and IAI-125A), palladium-103 (Pd-103; Model 200), and cesium-131 (Cs-131; Model Cs-1). Validation was performed for both line source and point source approximations. As part of the treatment planning validation, first a QA phantom (CIRS Brachytherapy QA Phantom Model 045 SN#D7210-3) containing three ellipsoid objects with certified volumes was scanned in order to check the volume accuracy of the contoured structures in MIM Symphony. Then the DICOM data containing 100 patient plans from the VariSeed TPS were imported into the MIM Symphony TPS. The 100 plans included 25 each of I-125 pre-implant plans, Pd-103 pre-implant plans, I-125 Day 30 plans (i.e., from 1 month after implantation), and Pd-103 Day 30 plans. The dosimetric parameters (including prostate volume, prostate D90 values, and rectum V100 values) of the 100 plans were calculated independently on the two TPSs. Other TPS tests that were done included verification of source input and geometrical accuracy, data transfer between different planning systems, text printout, 2D dose plots, DVH printout, and template grid accuracy. According to the line source formalism, the dosimetric results between the MIM Symphony TPS and TG-43 were within 0.5% (0.02 Gy) for r > 1 cm. In the line source approximation validation, MIM Symphony TPS values agreed with VariSeed TPS values to within 0.5% (0.09 Gy) for r > 1 cm. Similarly, in point source approximation validation, the MIM Symphony values

  3. Evaluation of the MIM Symphony treatment planning system for low-dose-rate- prostate brachytherapy.

    PubMed

    Dhanesar, Sandeep K; Lim, Tze Y; Du, Weiliang; Bruno, Teresa L; Frank, Steven J; Kudchadker, Rajat J

    2015-01-01

    MIM Symphony is a recently introduced low-dose-rate prostate brachytherapy treatment planning system (TPS). We evaluated the dosimetric and planning accuracy of this new TPS compared to the universally used VariSeed TPS. For dosimetric evaluation of the MIM Symphony version 5.4 TPS, we compared dose calculations from the MIM Symphony TPS with the formalism recommended by the American Association of Physicists in Medicine Task Group 43 report (TG-43) and those generated by the VariSeed version 8.0 TPS for iodine-125 (I-125; Models 6711 and IAI-125A), palladium-103 (Pd-103; Model 200), and cesium-131 (Cs-131; Model Cs-1). Validation was performed for both line source and point source approximations. As part of the treatment planning validation, first a QA phantom (CIRS Brachytherapy QA Phantom Model 045 SN#D7210-3) containing three ellipsoid objects with certified volumes was scanned in order to check the volume accuracy of the contoured structures in MIM Symphony. Then the DICOM data containing 100 patient plans from the VariSeed TPS were imported into the MIM Symphony TPS. The 100 plans included 25 each of I-125 pre-implant plans, Pd-103 pre-implant plans, I-125 Day 30 plans (i.e., from 1 month after implantation), and Pd-103 Day 30 plans. The dosimetric parameters (including prostate volume, prostate D90 values, and rectum V100 values) of the 100 plans were calculated independently on the two TPSs. Other TPS tests that were done included verification of source input and geometrical accuracy, data transfer between different planning systems, text printout, 2D dose plots, DVH printout, and template grid accuracy. According to the line source formalism, the dosimetric results between the MIM Symphony TPS and TG-43 were within 0.5% (0.02 Gy) for r > 1 cm. In the line source approximation validation, MIM Symphony TPS values agreed with VariSeed TPS values to within 0.5% (0.09 Gy) for r > 1 cm. Similarly, in point source approximation validation, the MIM Symphony values

  4. Interstitial rotating shield brachytherapy for prostate cancer

    SciTech Connect

    Adams, Quentin E. Xu, Jinghzu; Breitbach, Elizabeth K.; Li, Xing; Rockey, William R.; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.; Enger, Shirin A.

    2014-05-15

    Purpose: To present a novel needle, catheter, and radiation source system for interstitial rotating shield brachytherapy (I-RSBT) of the prostate. I-RSBT is a promising technique for reducing urethra, rectum, and bladder dose relative to conventional interstitial high-dose-rate brachytherapy (HDR-BT). Methods: A wire-mounted 62 GBq{sup 153}Gd source is proposed with an encapsulated diameter of 0.59 mm, active diameter of 0.44 mm, and active length of 10 mm. A concept model I-RSBT needle/catheter pair was constructed using concentric 50 and 75 μm thick nickel-titanium alloy (nitinol) tubes. The needle is 16-gauge (1.651 mm) in outer diameter and the catheter contains a 535 μm thick platinum shield. I-RSBT and conventional HDR-BT treatment plans for a prostate cancer patient were generated based on Monte Carlo dose calculations. In order to minimize urethral dose, urethral dose gradient volumes within 0–5 mm of the urethra surface were allowed to receive doses less than the prescribed dose of 100%. Results: The platinum shield reduced the dose rate on the shielded side of the source at 1 cm off-axis to 6.4% of the dose rate on the unshielded side. For the case considered, for the same minimum dose to the hottest 98% of the clinical target volume (D{sub 98%}), I-RSBT reduced urethral D{sub 0.1cc} below that of conventional HDR-BT by 29%, 33%, 38%, and 44% for urethral dose gradient volumes within 0, 1, 3, and 5 mm of the urethra surface, respectively. Percentages are expressed relative to the prescription dose of 100%. For the case considered, for the same urethral dose gradient volumes, rectum D{sub 1cc} was reduced by 7%, 6%, 6%, and 6%, respectively, and bladder D{sub 1cc} was reduced by 4%, 5%, 5%, and 6%, respectively. Treatment time to deliver 20 Gy with I-RSBT was 154 min with ten 62 GBq {sup 153}Gd sources. Conclusions: For the case considered, the proposed{sup 153}Gd-based I-RSBT system has the potential to lower the urethral dose relative to HDR-BT by 29

  5. Photoacoustic imaging of prostate brachytherapy seeds with transurethral light delivery

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Guo, Xiaoyu; Song, Danny Y.; Boctor, Emad M.

    2014-03-01

    We present a novel approach to photoacoustic imaging of prostate brachytherapy seeds utilizing an existing urinary catheter for transurethral light delivery. Two canine prostates were surgically implanted with brachyther- apy seeds under transrectal ultrasound guidance. One prostate was excised shortly after euthanasia and fixed in gelatin. The second prostate was imaged in the native tissue environment shortly after euthanasia. A urinary catheter was inserted in the urethra of each prostate. A 1-mm core diameter optical fiber coupled to a 1064 nm Nd:YAG laser was inserted into the urinary catheter. Light from the fiber was either directed mostly parallel to the fiber axis (i.e. end-fire fire) or mostly 90° to the fiber axis (i.e. side-fire fiber). An Ultrasonix SonixTouch scanner, transrectal ultrasound probe with curvilinear (BPC8-4) and linear (BPL9-5) arrays, and DAQ unit were utilized for synchronized laser light emission and photoacoustic signal acquisition. The implanted brachytherapy seeds were visualized at radial distances of 6-16 mm from the catheter. Multiple brachytherapy seeds were si- multaneously visualized with each array of the transrectal probe using both delay-and-sum (DAS) and short-lag spatial coherence (SLSC) beamforming. This work is the first to demonstrate the feasibility of photoacoustic imaging of prostate brachytherapy seeds using a transurethral light delivery method.

  6. Prostate brachytherapy in patients with median lobe hyperplasia.

    PubMed

    Wallner, K; Smathers, S; Sutlief, S; Corman, J; Ellis, W

    2000-06-20

    Our aim was to document the technical and clinical course of prostate brachytherapy patients with radiographic evidence of median lobe hyperplasia (MLH). Eight patients with MLH were identified during our routine brachytherapy practice, representing 9% of the 87 brachytherapy patients treated during a 6-month period. No effort was made to avoid brachytherapy in patients noted to have MLH on diagnostic work-up. Cystoscopic evaluation was not routinely performed. Postimplant axial computed tomographic (CT) images of the prostate were obtained at 0.5 cm intervals. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association (AUA). Each patient was contacted during the writing of this report to update postimplant morbidity information. There was no apparent association between the degree of MLH and preimplant prostate volume or AUA score. Intraoperatively, we were able to visualize MLH by transrectal ultrasound and did not notice any particular difficulty placing sources in the MLH tissue or migration of sources out of the tissue. The prescription isodose covered from 81% to 99% of the postimplant CT-defined target volume, achieving adequate dose to the median lobe tissue in all patients. Two of the eight patients developed acute, postimplant urinary retention. The first patient required intermittent self-catheterization for 3 months and then resumed spontaneous urination. MLH does not appear to be a strong contraindication to prostate brachytherapy, and prophylactic resection of hypertrophic tissue in such patients is probably not warranted. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 152-156 (2000). PMID:10900427

  7. Magnetic resonance spectroscopy-guided transperineal prostate biopsy and brachytherapy for recurrent prostate cancer.

    PubMed

    Barnes, Agnieszka Szot; Haker, Steven J; Mulkern, Robert V; So, Minna; D'Amico, Anthony V; Tempany, Clare M

    2005-12-01

    Brachytherapy targeted to the peripheral zone with magnetic resonance imaging (MRI) guidance is a prostate cancer treatment option with potentially fewer complications than other treatments. Follow-up MRI when failure is suspected is, however, difficult because of radiation-induced changes. Furthermore, MR spectroscopy (MRS) is compromised by susceptibility artifacts from radioactive seeds in the peripheral zone. We report a case in which combined MRI/MRS was useful for the detection of prostate cancer in the transitional zone in patients previously treated with MR-guided brachytherapy. We propose that MRI/MRS can help detect recurrent prostate cancer, guide prostate biopsy, and help manage salvage treatment decisions. PMID:16360468

  8. Brachytherapy versus prostatectomy in localized prostate cancer: Results of a French multicenter prospective medico-economic study

    SciTech Connect

    Buron, Catherine; Le Vu, Beatrice; Cosset, Jean-Marc; Peiffert, Didier; Delannes, Martine; Flam, Thierry; Guerif, Stephane; Salem, Naji; Chauveinc, Laurent; Livartowski, Alain . E-mail: alain.livartowski@curie.net

    2007-03-01

    Purpose: To prospectively compare health-related quality of life (HRQOL), patient-reported treatment-related symptoms, and costs of iodine-125 permanent implant interstitial brachytherapy (IB) with those of radical prostatectomy (RP) during the first 2 years after these treatments for localized prostate cancer. Methods and Materials: A total of 435 men with localized low-risk prostate cancer, from 11 French hospitals, treated with IB (308) or RP (127), were offered to complete the European Organization for Research and Treatment of Cancer core Quality of Life Questionnaire QLQ-C30 version 3 (EORTC QLQ-C30) and the prostate cancer specific EORTC QLQ-PR25 module before and at the end of treatment, 2, 6, 12, 18, and 24 months after treatment. Repeated measures analysis of variance and analysis of covariance were conducted on HRQOL changes. Comparative cost analysis covered initial treatment, hospital follow-up, outpatient and production loss costs. Results: Just after treatment, the decrease of global HRQOL was less pronounced in the IB than in the RP group, with a 13.5 points difference (p < 0.0001). A difference slightly in favor of RP was observed 6 months after treatment (-7.5 points, p = 0.0164) and was maintained at 24 months (-8.2 points, p = 0.0379). Impotence and urinary incontinence were more pronounced after RP, whereas urinary frequency, urgency, and urination pain were more frequent after IB. Mean societal costs did not differ between IB ( Euro 8,019 at T24) and RP ( Euro 8,715 at T24, p = 0.0843) regardless of the period. Conclusions: This study suggests a similar cost profile in France for IB and RP but with different HRQOL and side effect profiles. Those findings may be used to tailor localized prostate cancer treatments to suit individual patients' needs.

  9. Introduction of Transperineal Image-Guided Prostate Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2014-07-15

    The modern prostate brachytherapy procedure is characterized by ultrasound guidance, template assistance, and a return to a “closed” transperineal approach. This review traces the introduction and evolution of these elements and charts the development of the procedure from the ashes of previous, failed efforts.

  10. Radiobiological evaluation of low dose-rate prostate brachytherapy implants

    NASA Astrophysics Data System (ADS)

    Knaup, Courtney James

    Low dose-rate brachytherapy is a radiation therapy treatment for men with prostate cancer. While this treatment is common, the use of isotopes with varying dosimetric characteristics means that the prescription level and normal organ tolerances vary. Additionally, factors such as prostate edema, seed loss and seed migration may alter the dose distribution within the prostate. The goal of this work is to develop a radiobiological response tool based on spatial dose information which may be used to aid in treatment planning, post-implant evaluation and determination of the effects of prostate edema and seed migration. Aim 1: Evaluation of post-implant prostate edema and its dosimetric and biological effects. Aim 2: Incorporation of biological response to simplify post-implant evaluation. Aim 3: Incorporation of biological response to simplify treatment plan comparison. Aim 4: Radiobiologically based comparison of single and dual-isotope implants. Aim 5: Determine the dosimetric and radiobiological effects of seed disappearance and migration.

  11. Prostate Brachytherapy in Men {>=}75 Years of Age

    SciTech Connect

    Merrick, Gregory S. Wallner, Kent E.; Galbreath, Robert W.; Butler, Wayne M.; Brammer, Sarah G.; Allen, Zachariah A.; Adamovich, Edward

    2008-10-01

    Purpose: To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged {>=}75 years undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and August 2004, 145 consecutive patients aged {>=}75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level {<=}0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival. Results: Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer. Conclusions: After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients.

  12. Urethral toxicity after LDR brachytherapy: experience in Japan.

    PubMed

    Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

    2015-01-01

    Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy.

  13. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A.; Wallner, Kent E.

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase {>=}25%, 23% of men experienced a decrease {>=}25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  14. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    SciTech Connect

    Al-Qaisieh, Bashar; Mason, Josh; Bownes, Peter; Henry, Ann; Dickinson, Louise; Ahmed, Hashim U.; Emberton, Mark; Langley, Stephen

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focal (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a notable

  15. Ejaculatory Function After Permanent {sup 125}I Prostate Brachytherapy for Localized Prostate Cancer

    SciTech Connect

    Huyghe, Eric Delannes, Martine; Wagner, Fabien M.; Delaunay, Boris; Nohra, Joe; Thoulouzan, Matthieu; Shut-Yee, J. Yeung; Plante, Pierre; Soulie, Michel; Thonneau, Patrick; Bachaud, Jean Marc

    2009-05-01

    Purpose: Ejaculatory function is an underreported aspect of male sexuality in men treated for prostate cancer. We conducted the first detailed analysis of ejaculatory function in patients treated with permanent {sup 125}I prostate brachytherapy for localized prostate cancer. Patients and Methods: Of 270 sexually active men with localized prostate cancer treated with permanent {sup 125}I prostate brachytherapy, 241 (89%), with a mean age of 65 years (range, 43-80), responded to a mailed questionnaire derived from the Male Sexual Health Questionnaire regarding ejaculatory function. Five aspects of ejaculatory function were examined: frequency, volume, dry ejaculation, pleasure, and pain. Results: Of the 241 sexually active men, 81.3% had conserved ejaculatory function after prostate brachytherapy; however, the number of patients with rare/absent ejaculatory function was double the pretreatment number (p < .0001). The latter finding was correlated with age (p < .001) and the preimplant International Index of Erectile Function score (p < .001). However, 84.9% of patients with maintained ejaculatory function after implantation reported a reduced volume of ejaculate compared with 26.9% before (p < .001), with dry ejaculation accounting for 18.7% of these cases. After treatment, 30.3% of the patients experienced painful ejaculation compared with 12.9% before (p = .0001), and this was associated with a greater number of implanted needles (p = .021) and the existence of painful ejaculation before implantation (p < .0001). After implantation, 10% of patients who continued to be sexually active experienced no orgasm compared with only 1% before treatment. in addition, more patients experienced late/difficult or weak orgasms (p = .001). Conclusion: Most men treated with brachytherapy have conserved ejaculatory function after prostate brachytherapy. However, most of these men experience a reduction in volume and a deterioration in orgasm.

  16. Prognostic Importance of Small Prostate Size in Men Receiving Definitive Prostate Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Adamovich, Edward; Wallner, Kent E.

    2012-10-01

    Purpose: To assess whether small prostate size is an adverse prognostic factor in men undergoing brachytherapy in the same manner in which it seems to be for men undergoing radical prostatectomy. Methods and Materials: From April 1995 to June 2008, 2024 patients underwent brachytherapy by a single brachytherapist. Median follow-up was 7.4 years. The role of small prostate size ({<=}20 cm{sup 3}) as a prognostic factor for biochemical progression-free survival, cause-specific survival, and all-cause mortality was investigated. The differences in survival between men with small and larger prostates were compared using Kaplan-Meier curves and log-rank tests. Results: Median prostate size for the entire cohort was 32.7 cm{sup 3}. For the 167 men with small prostates, median prostate size was 17.4 cm{sup 3}. There was no difference in biochemical progression-free survival (95.2% vs 96.2%, P=.603), cause-specific survival (97.7% vs 98.3%, P=.546), or all-cause mortality (78.0% vs 77.2%, P=.838) at 10 years for men with small prostates compared with men with larger prostates. On univariate and multivariate analysis, small prostate size was not associated with any of the primary outcome measures. Conclusion: Men with small prostates treated with brachytherapy have excellent outcomes and are at no higher risk of treatment failure than men with larger glands. High-quality implants with adequate margins seem sufficient to address the increased adverse risk factors associated with small prostate size.

  17. Utilization of prostate brachytherapy for low risk prostate cancer: Is the decline overstated?

    PubMed Central

    Wong, Andrew; Weiner, Joseph P.; Schwartz, David; Schreiber, David

    2016-01-01

    Purpose Several prior studies have suggested that brachytherapy utilization has markedly decreased, coinciding with the recent increased utilization of intensity modulated radiation therapy, as well as an increase in urologist-owned centers. We sought to investigate the brachytherapy utilization in a large, hospital-based registry. Material and methods Men with prostate cancer diagnosed between 2004-2012 and treated with either external beam radiation and/or prostate brachytherapy were abstracted from the National Cancer Database. In order to be included, men had to be clinically staged as T1c-T2aNx-0Mx-0, Gleason 6, PSA ≤ 10.0 ng/ml. Descriptive statistics were used to analyze brachytherapy utilization over time and were compared via χ2. Multivariate logistic regression was used to assess for covariables associated with increased brachytherapy usage. Results There were 89,413 men included in this study, of which 37,054 (41.6%) received only external beam radiation, and 52,089 (58.4%) received prostate brachytherapy. The use of brachytherapy declined over time from 62.9% in 2004 to 51.3% in 2012 (p < 0.001). This decline was noted in both academic facilities (60.8% in 2004 to 47.0% in 2012, p < 0.001) as well as in non-academic facilities (63.7% in 2004 to 53.0% in 2012, p < 0.001). The decline was more pronounced in patients who lived closer to treatment facilities than those who lived further. The use of intensity modulated radiation therapy increased during this same time period from 18.4% in 2004 to 38.2% in 2012 (p < 0.001). On multivariate analysis, treatment at an academic center, increasing age, decreasing distance from the treatment center, and years of diagnosis from 2006-2012 were significantly associated with reduced brachytherapy usage. Conclusions In this hospital-based registry, prostate brachytherapy usage has declined for low risk prostate cancer as intensity modulated radiation therapy usage has increased. However, it still remains the

  18. Utilization of prostate brachytherapy for low risk prostate cancer: Is the decline overstated?

    PubMed Central

    Wong, Andrew; Weiner, Joseph P.; Schwartz, David; Schreiber, David

    2016-01-01

    Purpose Several prior studies have suggested that brachytherapy utilization has markedly decreased, coinciding with the recent increased utilization of intensity modulated radiation therapy, as well as an increase in urologist-owned centers. We sought to investigate the brachytherapy utilization in a large, hospital-based registry. Material and methods Men with prostate cancer diagnosed between 2004-2012 and treated with either external beam radiation and/or prostate brachytherapy were abstracted from the National Cancer Database. In order to be included, men had to be clinically staged as T1c-T2aNx-0Mx-0, Gleason 6, PSA ≤ 10.0 ng/ml. Descriptive statistics were used to analyze brachytherapy utilization over time and were compared via χ2. Multivariate logistic regression was used to assess for covariables associated with increased brachytherapy usage. Results There were 89,413 men included in this study, of which 37,054 (41.6%) received only external beam radiation, and 52,089 (58.4%) received prostate brachytherapy. The use of brachytherapy declined over time from 62.9% in 2004 to 51.3% in 2012 (p < 0.001). This decline was noted in both academic facilities (60.8% in 2004 to 47.0% in 2012, p < 0.001) as well as in non-academic facilities (63.7% in 2004 to 53.0% in 2012, p < 0.001). The decline was more pronounced in patients who lived closer to treatment facilities than those who lived further. The use of intensity modulated radiation therapy increased during this same time period from 18.4% in 2004 to 38.2% in 2012 (p < 0.001). On multivariate analysis, treatment at an academic center, increasing age, decreasing distance from the treatment center, and years of diagnosis from 2006-2012 were significantly associated with reduced brachytherapy usage. Conclusions In this hospital-based registry, prostate brachytherapy usage has declined for low risk prostate cancer as intensity modulated radiation therapy usage has increased. However, it still remains the

  19. Primary Gleason Grade 4 Impact on Biochemical Recurrence After Permanent Interstitial Brachytherapy in Japanese Patients With Low- or Intermediate-Risk Prostate Cancer

    SciTech Connect

    Uesugi, Tatsuya; Saika, Takashi; Edamura, Kohei; Nose, Hiroyuki; Kobuke, Makoto; Ebara, Shin; Abarzua, Fernand; Katayama, Norihisa; Yanai, Hiroyuki; Nasu, Yasutomo; Kumon, Hiromi

    2012-02-01

    Purpose: To reveal a predictive factor for biochemical recurrence (BCR) after permanent prostate brachytherapy (PPB) using iodine-125 seed implantation in patients with localized prostate cancer classified as low or intermediate risk based on National Comprehensive Cancer Network (NCCN) guidelines. Methods and Materials: From January 2004 to December 2009, 414 consecutive Japanese patients with clinically localized prostate cancer classified as low or intermediate risk based on the NCCN guidelines were treated with PPB. The clinical factors including pathological data reviewed by a central pathologist and follow-up data were prospectively collected. Kaplan-Meier and Cox regression analyses were used to assess the factors associated with BCR. Results: Median follow-up was 36.5 months. The 2-, 3-, 4-, and 5-year BCR-free rates using the Phoenix definition were 98.3%, 96.0%, 91.6%, and 87.0%, respectively. On univariate analysis, the Gleason score, especially primary Gleason grade 4 in biopsy specimens, was a strong predicting factor (p < 0.0001), while age, initial prostate-specific antigen (PSA) level, T stage, and minimal dose delivered to 90% of the prostate volume (D90) were insignificant. Multivariate analysis indicated that a primary Gleason grade 4 was the most powerful prognostic factor associated with BCR (hazard ratio = 6.576, 95% confidence interval, 2.597-16.468, p < 0.0001). Conclusions: A primary Gleason grade 4 carried a worse BCR prognosis than the primary grade 3 in patients treated with PPB. Therefore, the indication for PPB in patients with a Gleason sum of 4 + 3 deserves careful and thoughtful consideration.

  20. Perineural invasion on prostate needle biopsy does not predict biochemical failure following brachytherapy for prostate cancer

    SciTech Connect

    Weight, Christopher J.; Ciezki, Jay P.; Reddy, Chandana A.; Zhou Ming; Klein, Eric A.

    2006-06-01

    Purpose: To determine if the presence of perineural invasion (PNI) predicts biochemical recurrence in patients who underwent low-dose-rate brachytherapy for the treatment of localized prostate cancer. Methods and Materials: A retrospective case control matching study was performed. The records of 651 patients treated with brachytherapy between 1996 and 2003 were reviewed. Sixty-three of these patients developed biochemical failure. These sixty-three patients were then matched in a one-to-one ratio to patients without biochemical failure, controlling for biopsy Gleason score, clinical stage, initial prostate-specific antigen, age, and the use of androgen deprivation. The pathology of the entire cohort was then reviewed for evidence of perineural invasion on initial prostate biopsy specimens. The biochemical relapse free survival rates for these two groups were compared. Results: Cases and controls were well matched, and there were no significant differences between the two groups in age, Gleason grade, clinical stage, initial prostate-specific antigen, and the use of androgen deprivation. PNI was found in 19 (17%) patients. There was no significant difference in the rates of PNI between cases and controls, 19.6% and 14.3% respectively (p 0.45). PNI did not correlate with biochemical relapse free survival (p 0.40). Conclusion: Perineural invasion is not a significant predictor of biochemical recurrence in patients undergoing brachytherapy for prostate cancer.

  1. Permanent Prostate Brachytherapy in Prostate Glands <20 cm{sup 3}

    SciTech Connect

    Mayadev, Jyoti; Merrick, Gregory S.; Reed, Joshua R.; Butler, Wayne M.; Galbreath, Robert W.; Allen, Zachariah A.; Wallner, Kent E.

    2010-04-15

    Purpose: To investigate the dosimetry, treatment-related morbidity, and biochemical outcomes for brachytherapy in patients with prostate glands <20 cm{sup 3}. Methods and Materials: From November 1996 to October 2006, 104 patients with prostate glands <20 cm{sup 3} underwent brachytherapy. Multiple prostate, urethral, and rectal dosimetric parameters were evaluated. Treatment-related urinary and rectal morbidity were assessed from patient questionnaires. Cause-specific survival, biochemical progression-free survival, and overall survival were recorded. Results: The median patient age, follow up, and pre-treatment ultrasound volume was 64 years, 5.0 years and 17.6cm{sup 3}, respectively. Median day 0 dosimetry was significant for the following: V100 98.5%, D90 126.1% and R100 <0.5% of prescription dose. The mean urethral and maximum urethral doses were 119.6% and 133.8% of prescription. The median time to International Prostate Symptom Score resolution was 4 months. There were no RTOG grade III or IV rectal complications. The cause-specific survival, biochemical progression-free survival, and overall survival rates were 100%, 92.5%, and 77.8% at 9 years. For biochemically disease-free patients, the median most recent postbrachytherapy PSA value was 0.02 ng/mL. Conclusion: Our results demonstrate that brachytherapy for small prostate glands is highly effective, with an acceptable morbidity profile, excellent postimplant dosimetry, acceptable treatment-related morbidity, and favorable biochemical outcomes.

  2. Comparison of biochemical failure definitions for permanent prostate brachytherapy

    SciTech Connect

    Kuban, Deborah A. . E-mail: dakuban@mdanderson.org; Levy, Larry B.; Potters, Louis; Beyer, David C.; Blasko, John C.; Moran, Brian J.; Ciezki, Jay P.; Zietman, Anthony L.; Zelefsky, Michael J.; Pisansky, Thomas M.; Elshaikh, Mohamed; Horwitz, Eric M.

    2006-08-01

    Purpose: To assess prostate-specific antigen (PSA) failure definitions for patients with Stage T1-T2 prostate cancer treated by permanent prostate brachytherapy. Methods and Materials: A total of 2,693 patients treated with radioisotopic implant as solitary treatment for T1-T2 prostatic adenocarcinoma were studied. All patients had a pretreatment PSA, were treated at least 5 years before analysis, 1988 to 1998, and did not receive hormonal therapy before recurrence. Multiple PSA failure definitions were tested for their ability to predict clinical failure. Results: Definitions which determined failure by a certain increment of PSA rise above the lowest PSA level to date (nadir + x ng/mL) were more sensitive and specific than failure definitions based on PSA doubling time or a certain number of PSA rises. The sensitivity and specificity for the nadir + 2 definition were 72% and 83%, vs. 51% and 81% for 3 PSA rises. The surgical type definitions (PSA exceeding an absolute value) could match this sensitivity and specificity but only when failure was defined as exceeding a PSA level in the 1-3 ng/mL range and only when patients were allowed adequate time to nadir. When failure definitions were compared by time varying covariate regression analysis, nadir + 2 ng/mL retained the best fit. Conclusions: For patients treated by permanent radioisotopic implant for prostate cancer, the definition nadir + 2 ng/mL provides the best surrogate for failure throughout the entire follow-up period, similar to patients treated by external beam radiotherapy. Therefore, the same PSA failure definition could be used for both modalities. For brachytherapy patients with long-term follow-up, at least 6 years, defining failure as exceeding an absolute PSA level in the 0.5 ng/mL range may be reasonable.

  3. Primary Causes of Death After Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Brammer, Sarah G.; Moyad, Mark

    2008-10-01

    Purpose: To evaluate the primary causes of death in low-risk (low-risk), intermediate-risk (intermediate-risk), and high-risk (high-risk) patients undergoing permanent prostate brachytherapy with or without supplemental therapies. Methods and Materials: From April 1995 through November 2004, a total of 1,354 consecutive patients underwent prostate brachytherapy. All patients underwent brachytherapy >3 years before analysis. Of the patients, 532 (39.3%) received androgen deprivation therapy and 703 (51.9%) received supplemental radiation therapy. The median follow-up was 5.4 years. Multiple parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific survival was 97.0% (99.7%, 99.0%, and 90.1% for low-risk, intermediate-risk, and high-risk patients). Overall survival was 76.7% (82.5%, 78.3%, and 67.6% for low-, intermediate-, and high-risk patients, respectively). The cumulative death rate for cardiovascular disease was 11.5% (8.7%, 9.3%, and 19.8% for low-, intermediate-, and high-risk patients). The death rate from second malignancies (nonprostate cancer) was 7.2% and was not substantially different when stratified by risk group. Death from all other causes was 6.5% for the entire cohort but 1.3%, 5.0%, and 10.8% for low-, intermediate-, and high-risk patients. In multivariate analysis, death from prostate cancer was best predicted by Gleason score and risk group, whereas death from cardiovascular disease, nonprostate cancer, and all other causes were most closely related to patient age and tobacco use. Conclusions: Although cardiovascular mortality was the predominant cause of death, prostate cancer was responsible for approximately 10% of all deaths. In particular, overall survival was poorest in the high-risk group. Although high-risk patients were most likely to die of prostate cancer, the divergence in overall survival between high-risk and lower-risk patients primarily

  4. Anisotropy Characterization of I-125 Seed with Attached Encapsulated Cobalt Chloride Complex Contrast Agent Markers for MRI-Based Prostate Brachytherapy

    SciTech Connect

    Frank, Steven J.; Tailor, Ramesh C.; Kudchadker, Rajat J.; Martirosyan, Karen S.; Stafford, R. Jason; Elliott, Andrew M.; Swanson, David A.; Sing, David; Choi, Jonathan; Mourtada, Firas; Ibbott, Geoffrey S.

    2011-07-01

    We have developed a novel MRI marker for prostate brachytherapy. The purpose of this study was to evaluate the changes in anisotropy when cobalt chloride complex contrast agent encapsulated contrast agent markers (C4-ECAM) were placed adjacent to an iodine-125 (I-125) titanium seed, and to verify that the C4-ECAMs were visible on magnetic resonance imaging (MRI) after radiation exposure. Two C4-ECAMs were verified to be MRI visible in a phantom before radiation exposure. The C4-ECAMs were then attached to each end of a 12.7-U (10-mCi) I-125 titanium seed in a polymer tube. Anisotropy was measured and analyzed with the seed alone and with attached C4-ECAMs by suspending thermoluminescent dosimeters in a water phantom in 2 circles surrounding the radioactive source with radius of 1 or 2 cm. A T1-weighted MRI evaluation of C4-ECAMs was then performed after exposure to the amount of radiation typically delivered during 1 month of prostate brachytherapy. Measured values of the anisotropy function F(r, {theta}) for the I-125 seed with and without the C4-ECAMs were mutually statistically indistinguishable (standard error of the mean <4.2%) and agreed well with published TG-43 values for the bare seed. As expected, the anisotropy function {phi}{sub an}(r) for the 2 datasets (with and without C4-ECAMs) derived from the measured F(r, {theta}) did not exhibit statistically measurable difference. Both datasets showed agreement with the published TG-43 {phi}{sub an}(r) for the bare seed. The C4-ECAMs were well visualized by MRI after 1 month of radiation exposure. There were no changes in anisotropy when the C4-ECAMs were placed next to an I-125 radioactive seed, and the C4-ECAMs were visualized after radiation exposure.

  5. Late rectal complications after prostate brachytherapy for localized prostate cancer: incidence and management.

    PubMed

    Phan, Jack; Swanson, David A; Levy, Lawrence B; Kudchadker, Rajat J; Bruno, Teresa L; Frank, Steven J

    2009-05-01

    This review of the literature on late rectal complications after prostate brachytherapy indicated that it is a highly effective treatment modality for patients with clinically localized prostate cancer but can cause chronic radiation proctitis. The most common manifestation of chronic radiation proctitis was anterior rectal wall bleeding, which often occurred within the first 2 years after brachytherapy. It is interesting to note that the rates of late rectal morbidity appear to have declined over time, which may reflect improvements in implantation techniques and imaging. Rectal biopsy as part of the workup to evaluate rectal bleeding can lead to rectal fistula and the need for colostomy, a rare but major complication. The authors recommend 1) screening colonoscopy before brachytherapy for patients who have not had a screening colonoscopy within the preceding 3 years to rule out colorectal malignancies and, thus, facilitate conservative management should rectal bleeding occur; 2) lifestyle modifications during treatment to limit exposure of the rectum to radiation; and 3) conservative management for rectal bleeding that occurs within 2 years after brachytherapy. Cancer 2009. (c) 2009 American Cancer Society.

  6. Report of a consensus meeting on focal low dose rate brachytherapy for prostate cancer.

    PubMed

    Langley, Stephen; Ahmed, Hashim U; Al-Qaisieh, Bashar; Bostwick, David; Dickinson, Louise; Veiga, Francisco Gomez; Grimm, Peter; Machtens, Stefan; Guedea, Ferran; Emberton, Mark

    2012-02-01

    What's known on the subject? and What does the study add? Whole gland brachytherapy has been used to successfully treat prostate cancer but the protocol for focal therapy has not previously been established. The consensus findings provide guidance on patient selection for focal brachytherapy as well as recommendations for conducting therapy and patient follow-up. Low dose rate prostate brachytherapy is an effective treatment for localized prostate cancer. Recently, it has been considered for use in a focused manner whereby treatment is targeted only to areas of prostate cancer. The objective of focal brachytherapy is to provide effective cancer control for low-risk disease but with reduced genitourinary and rectal side-effects in a cost-effective way. We report on the outputs of a consensus meeting of international experts in brachytherapy and focal therapy convened to consider the feasibility and potential development of focal brachytherapy. A number of factors were considered for focal brachytherapy including optimal patient selection, disease characterization and localization, treatment protocols and outcome measures. The consensus meeting also addressed the design of a clinical trial that would assess the oncological outcomes and side-effect profiles resulting from focal brachytherapy. PMID:22239224

  7. Sequential evaluation of prostate edema after permanent seed prostate brachytherapy using CT-MRI fusion

    SciTech Connect

    Taussky, Daniel; Austen, Lyn; Toi, Ants; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: juanita.crook@rmp.uhn.on.ca

    2005-07-15

    Purpose: To analyze the extent and time course of prostate edema and its effect on dosimetry after permanent seed prostate brachytherapy. Methods and Materials: Twenty patients scheduled for permanent seed {sup 125}I prostate brachytherapy agreed to a prospective study on postimplant edema. Implants were preplanned using transrectal ultrasonography. Postimplant dosimetry was calculated using computed tomography-magnetic resonance imaging (CT-MRI) fusion on the day of the implant (Day 1) and Days 8 and 30. The prostate was contoured on MRI, and the seeds were located on CT. Factors investigated for an influence on edema were the number of seeds and needles, preimplant prostate volume, transitional zone index (transition zone volume divided by prostate volume), age, and prostate-specific antigen level. Prostate dosimetry was evaluated by the percentage of the prostate volume receiving 100% of the prescribed dose (V{sub 100}) and percentage of prescribed dose received by 90% of the prostate volume (D{sub 90}). Results: Prostate edema was maximal on Day 1, with the median prostate volume 31% greater than preimplant transrectal ultrasound volume (range, 0.93-1.72; p < 0.001) and decreased with time. It was 21% greater than baseline at Day 8 (p = 0.013) and 5% greater on Day 30 (p < 0.001). Three patients still had a prostate volume greater than baseline by Day 30. The extent of edema depended on the transition zone volume (p = 0.016) and the preplan prostate volume (p 0.003). The median V{sub 100} on Day 1 was 93.6% (range, 86.0-98.2%) and was 96.3% (range, 85.7-99.5%) on Day 30 (p = 0.079). Patients with a Day 1 V{sub 100} >93% were less affected by edema resolution, showing a median increase in V{sub 100} of 0.67% on Day 30 compared with 2.77% for patients with a V{sub 100} <93 % on Day 1. Conclusion: Despite the extreme range of postimplant edema, the effect on dosimetry was less than expected. Dose coverage of the prostate was good for all patients during Days 1

  8. Prostate Brachytherapy seed migration to the Bladder presenting with Gross Hematuria.

    PubMed

    Haroun, Reham R; Nance, John W; Fishman, Elliot K

    2016-01-01

    We present the radiologic findings in a case of prostate brachytherapy seed migration to the bladder presenting as gross hematuria. While prostate brachytherapy seed implantation is considered a relatively safe procedure, migration is not uncommon; however, it is usually clinically silent and the seeds most commonly migrate to the lungs through the venous circulation via the periprostatic venous plexus. Our case illustrates that local erosion is possible, can be symptomatic, and therefore must be considered when evaluating select patients. PMID:27200152

  9. Prostate Brachytherapy seed migration to the Bladder presenting with Gross Hematuria

    PubMed Central

    Haroun, Reham R; Nance, John W; Fishman, Elliot K

    2016-01-01

    We present the radiologic findings in a case of prostate brachytherapy seed migration to the bladder presenting as gross hematuria. While prostate brachytherapy seed implantation is considered a relatively safe procedure, migration is not uncommon; however, it is usually clinically silent and the seeds most commonly migrate to the lungs through the venous circulation via the periprostatic venous plexus. Our case illustrates that local erosion is possible, can be symptomatic, and therefore must be considered when evaluating select patients. PMID:27200152

  10. Patient perception of local anesthesia for prostate brachytherapy.

    PubMed

    Smathers, S; Wallner, K; Simpson, C; Roof, J

    2000-05-01

    Prostate brachytherapy is an increasingly popular treatment for early-stage prostate cancer. Until now, spinal or general anesthesia for the procedure has been the standard of care. For patient safety, patient convenience, and to limit use of operating facilities, the authors started performing implants routinely with local anesthesia. We present here an evaluation of patients' acceptance of prostate brachytherapy under local anesthesia. On arrival at our department on the morning of the procedure, the patient is brought into the simulator suite, an intravenous line is started, and a urinary catheter is inserted. With the patient in the lithotomy position, a 5-by-5-cm patch of perineal skin and subcutaneous tissue is anesthetized by local infiltration of 10 mL of 1% lidocaine, using a 25-gauge 5/8-inch needle. Immediately following injection into the subcutaneous tissues, the deeper tissues, including the pelvic floor and prostate apex, are anesthetized by injecting 15 mL lidocaine solution with approximately 8 passes of a 20-gauge 1-inch needle. Following subcutaneous and periapical lidocaine injections, the transrectal ultrasound (TRUS) probe is positioned to reproduce the planning images and a 3.5- or 6-inch, 22-gauge spinal needle is inserted into the peripheral planned needle tracks, monitored by TRUS. When the tips of the needles reach the prostatic base, about 1 mL of lidocaine solution is injected in the intraprostatic track, as the needle is slowly withdrawn. The lidocaine infiltration procedure takes approximately 10 to 15 minutes. Seed implantation is then performed as previously described. At the time of this report preparation, 58 of the 71 patients (81%) were interviewed, with a median follow-up of 6 months since the implant procedure. On a scale of 1 to 10, the median biopsy pain score was 4.5 compared with a median pain score with the implant procedure of 3.0. There was no clear correlation between the two scores (r = .26). There was no correlation

  11. The influence of isotope and prostate volume on urinary morbidity after prostate brachytherapy

    SciTech Connect

    Niehaus, Angela; Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Galbreath, Robert W.; Adamovich, Edward

    2006-01-01

    Purpose: To evaluate the influence of isotope and prostate size on International Prostate Symptom Score (IPSS) normalization, catheter dependency, and the need for surgical intervention secondary to bladder outlet obstruction after prostate brachytherapy. Methods and Materials: Between January 1998 and June 2003, 976 consecutive patients underwent brachytherapy for clinical stage T1b-T3a (2002 American Joint Committee on Cancer) prostate cancer. Seven hundred eighty-nine (80.8%) were implanted with {sup 103}Pd and 187 (19.2%) with {sup 125}I. The median follow-up was 41.2 months. Patients were stratified into size cohorts {<=}25 cm{sup 3}, 25.1-35 cm{sup 3}, 35.1-45 cm{sup 3}, and >45 cm{sup 3}. Four hundred eighteen patients (42.8%) received androgen deprivation therapy (ADT). Four hundred eighty-six patients (49.7%) received supplemental external-beam radiation therapy (XRT). In all patients, an alpha blocker was initiated before implantation and continued at least until the IPSS returned to baseline. IPSS resolution was defined as a return to within one point of baseline. The median number of IPSS determinations per patient was 21. Clinical, treatment, and dosimetric parameters evaluated included patient age, pretreatment PSA, Gleason score, clinical T stage, percent positive biopsies, preimplant IPSS, ultrasound volume, planning volume, isotope, V{sub 100/150/20}, D{sub 9}, urethral dose (average and maximum), supplemental XRT, ADT, and the duration of ADT ({<=}6 months vs. >6 months). Catheter dependency and the need for postsurgical intervention were also evaluated. Results: For both isotopes and all prostate size cohorts, IPSS peaked 1 month after implantation and returned to baseline at a mean of 1.9 months. Stratification of prostate size cohorts by isotope demonstrated no significant differences in prolonged catheter dependency ({>=}5 days), IPSS resolution, or postimplant surgical intervention. In Cox regression analysis, IPSS normalization was best

  12. In vivo visualization of prostate brachytherapy seeds with photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Kuo, Nathanael P.; Song, Danny Y.; Kang, Jin U.; Boctor, Emad M.

    2014-12-01

    We conducted a canine study to investigate the in vivo feasibility of photoacoustic imaging for intraoperative updates to brachytherapy treatment plans. A fiber coupled to a 1064-nm Nd:YAG laser was inserted into high-dose-rate brachytherapy needles, which diffused light spherically. These needles were inserted through the perineum into the prostate for interstitial light delivery and the resulting acoustic waves were detected with a transrectal ultrasound probe. Postoperative computed tomography images and ex vivo photoacoustic images confirmed seed locations. Limitations with insufficient light delivery were mitigated with short-lag spatial coherence (SLSC) beamforming, providing a 10-20 dB contrast improvement over delay-and-sum (DAS) beamforming for pulse energies ranging from 6.8 to 10.5 mJ with a fiber-seed distance as large as 9.5 mm. For the same distance and the same range of energy densities, signal-to-noise ratios (SNRs) were similar while the contrast-to-noise ratio (CNR) was higher in SLSC compared to DAS images. Challenges included visualization of signals associated with the interstitial fiber tip and acoustic reverberations between seeds separated by ≤2 mm. Results provide insights into the potential for clinical translation to humans.

  13. Incidence of Second Malignancies in Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy and Radical Prostatectomy

    SciTech Connect

    Hamilton, Sarah Nicole; Tyldesley, Scott; Hamm, Jeremy; Jiang, Wei Ning; Keyes, Mira; Pickles, Tom; Lapointe, Vince; Kahnamelli, Adam; McKenzie, Michael; Miller, Stacy; Morris, W. James

    2014-11-15

    Purpose: To compare the second malignancy incidence in prostate cancer patients treated with brachytherapy (BT) relative to radical prostatectomy (RP) and to compare both groups with the cancer incidence in the general population. Methods and Materials: From 1998 to 2010, 2418 patients were treated with Iodine 125 prostate BT monotherapy at the British Columbia Cancer Agency, and 4015 referred patients were treated with RP. Cancer incidence was compared with the age-matched general population using standardized incidence ratios (SIRs). Pelvic malignancies included invasive and noninvasive bladder cancer and rectal cancer. Cox multivariable analysis was performed with adjustment for covariates to determine whether treatment (RP vs BT) was associated with second malignancy risk. Results: The median age at BT was 66 years and at RP 62 years. The SIR comparing BT patients with the general population was 1.06 (95% confidence interval [CI] 0.91-1.22) for second malignancy and was 1.53 (95% CI 1.12-2.04) for pelvic malignancy. The SIR comparing RP patients with the general population was 1.11 (95% CI 0.98-1.25) for second malignancy and was 1.11 (95% CI 0.82-1.48) for pelvic malignancy. On multivariable analysis, older age (hazard ratio [HR] 1.05) and smoking (HR 1.65) were associated with increased second malignancy risk (P<.0001). Radical prostatectomy was not associated with a decreased second malignancy risk relative to BT (HR 0.90, P=.43), even when excluding patients who received postprostatectomy external beam radiation therapy (HR 1.13, P=.25). Older age (HR 1.09, P<.0001) and smoking (HR 2.17, P=.0009) were associated with increased pelvic malignancy risk. Radical prostatectomy was not associated with a decreased pelvic malignancy risk compared with BT (HR 0.57, P=.082), even when excluding postprostatectomy external beam radiation therapy patients (HR 0.87, P=.56). Conclusions: After adjustment for covariates, BT patients did not have an increased second

  14. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer.

    PubMed

    Murali, V; Kurup, P G G; Mahadev, P; Mahalakshmi, S

    2010-04-01

    Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.

  15. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer

    PubMed Central

    Murali, V.; Kurup, P. G. G.; Mahadev, P.; Mahalakshmi, S.

    2010-01-01

    Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage. PMID:20589121

  16. Body Mass Index and Prostate-Specific Antigen Failure Following Brachytherapy for Localized Prostate Cancer

    SciTech Connect

    Efstathiou, Jason A. Skowronski, Rafi Y.; Coen, John J.; Grocela, Joseph A.; Hirsch, Ariel E.; Zietman, Anthony L.

    2008-08-01

    Purpose: Increasing body mass index (BMI) is associated with prostate-specific antigen (PSA) failure after radical prostatectomy and external beam radiation therapy (EBRT). We investigated whether BMI is associated with PSA failure in men treated with brachytherapy for clinically localized prostate cancer. Patients and Methods: Retrospective analyses were conducted on 374 patients undergoing brachytherapy for stage T1c-T2cNXM0 prostate cancer from 1996-2001. Forty-nine patients (13%) received supplemental EBRT and 131 (35%) received androgen deprivation therapy (ADT). Height and weight data were available for 353 (94%). Cox regression analyses were performed to evaluate the relationship between BMI and PSA failure (nadir + 2 ng/ml definition). Covariates included age, race, preimplantation PSA, Gleason score, T category, percent of prescription dose to 90% of the prostate, use of supplemental EBRT, and ADT. Results: Median age, PSA, and BMI were 66 years (range, 42-80 years), 5.7 ng/ml (range, 0.4-22.6 ng/ml), and 27.1 kg/m{sup 2} (range, 18.2-53.6 kg/m{sup 2}), respectively. After a median follow-up of 6.0 years (range, 3.0-10.2 years), there were 76 PSA recurrences. The BMI was not associated with PSA failure. Six-year PSA failure rates were 30.2% for men with BMI less than 25 kg/m{sup 2}, 19.5% for BMI of 25 or greater to less than 30 kg/m{sup 2}, and 14.4% for BMI of 30 kg/m{sup 2} or greater (p = 0.19). Results were similar when BMI was analyzed as a continuous variable, using alternative definitions of PSA failure, and excluding patients treated with EBRT and/or ADT. In multivariate analyses, only baseline PSA was significantly associated with shorter time to PSA failure (adjusted hazard ratio, 1.12; 95% confidence interval, 1.05-1.20; p 0.0006). Conclusions: Unlike after surgery or EBRT, BMI is not associated with PSA failure in men treated with brachytherapy for prostate cancer. This raises the possibility that brachytherapy may be a preferred treatment

  17. Comparison of seed loading approaches in prostate brachytherapy.

    PubMed

    Butler, W M; Merrick, G S; Lief, J H; Dorsey, A T

    2000-02-01

    Since uniform seed loading in prostate brachytherapy can produce an intolerably high dose along the urethra, some form of peripheral loading is commonly employed. We define three variants of peripheral loading and compare them in a small, medium, and large prostate in terms of coverage of the planning target volume (PTV), homogeneity, and ability to spare critical structures of excessive dose. Modified uniform loading has at least 2/3 of the seeds occupying sites on a 1 cm cubic grid keyed to the prostate base and the posterior border of the prostate. Nonuniform loading explicitly spares the urethra by using only basal and apical seeds in at least two centrally located needles. Peripheral loading uses higher activity seeds with the posterior implant plane 5 mm anterior to the posterior border of the prostate. The three prostate volumes (18.7, 40.7, and 60.2 cm3 by ultrasound) were expanded to planning volumes (32.9, 60.0, and 87.8 cm3, respectively). The planning volumes (PTVs) were loaded with a 125I seed distribution and activity sufficient to cover 99.7+/-0.3% of the PTV with the prescribed minimal peripheral dose (mPD) of 145 Gy. Activities used ranged from 0.32 to 0.37 mCi/seed (0.41-0.47 U/seed) for the first two approaches and from 0.57 to 0.66 mCi (0.72-0.84 U) for peripheral loading. Modified uniform loading produced the most uniform distribution based on dose-volume histograms and the volume receiving >150% of prescribed dose. All the approaches are capable of constraining the superior-inferior dose profile (the urethral path) to less than 150% of the mPD, but the nonuniform approach with explicit urethral sparing kept the urethral dose below 120% of the mPD. Dose profiles for the three approaches along the posterior-anterior midline axis are comparable near the urethra, but peripheral and nonuniform approaches have extended regions where the dose is >150% of mPD. These regions approach within 10 mm of the rectum or urethra, so these two approaches

  18. AAPM Task Group 128: Quality assurance tests for prostate brachytherapy ultrasound systems

    SciTech Connect

    Pfeiffer, Douglas; Sutlief, Steven; Feng Wenzheng; Pierce, Heather M.; Kofler, Jim

    2008-12-15

    While ultrasound guided prostate brachytherapy has gained wide acceptance as a primary treatment tool for prostate cancer, quality assurance of the ultrasound guidance system has received very little attention. Task Group 128 of the American Association of Physicists in Medicine was created to address quality assurance requirements specific to transrectal ultrasound used for guidance of prostate brachytherapy. Accurate imaging guidance and dosimetry calculation depend upon the quality and accuracy of the ultrasound image. Therefore, a robust quality assurance program for the ultrasound system is essential. A brief review of prostate brachytherapy and ultrasound physics is provided, followed by a recommendation for elements to be included in a comprehensive test phantom. Specific test recommendations are presented, covering grayscale visibility, depth of penetration, axial and lateral resolution, distance measurement, area measurement, volume measurement, needle template/electronic grid alignment, and geometric consistency with the treatment planning computer.

  19. Dose to the Bladder Neck Is the Most Important Predictor for Acute and Late Toxicity After Low-Dose-Rate Prostate Brachytherapy: Implications for Establishing New Dose Constraints for Treatment Planning

    SciTech Connect

    Hathout, Lara; Folkert, Michael R.; Kollmeier, Marisa A.; Yamada, Yoshiya; Cohen, Gil'ad N.; Zelefsky, Michael J.

    2014-10-01

    Purpose: To identify an anatomic structure predictive for acute (AUT) and late (LUT) urinary toxicity in patients with prostate cancer treated with low-dose-rate brachytherapy (LDR) with or without external beam radiation therapy (EBRT). Methods and Materials: From July 2002 to January 2013, 927 patients with prostate cancer (median age, 66 years) underwent LDR brachytherapy with Iodine 125 (n=753) or Palladium 103 (n=174) as definitive treatment (n=478) and as a boost (n=449) followed by supplemental EBRT (median dose, 50.4 Gy). Structures contoured on the computed tomographic (CT) scan on day 0 after implantation included prostate, urethra, bladder, and the bladder neck, defined as 5 mm around the urethra between the catheter balloon and the prostatic urethra. AUT and LUT were assessed with the Common Terminology Criteria for Adverse Events, version4. Clinical and dosimetric factors associated with AUT and LUT were analyzed with Cox regression and receiver operating characteristic analysis to calculate area under the receiver operator curve (ROC) (AUC). Results: Grade ≥2 AUT and grade ≥2 LUT occurred in 520 patients (56%) and 154 patients (20%), respectively. No grade 4 toxicities were observed. Bladder neck D2cc retained a significant association with AUT (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.03-1.04; P<.0001) and LUT (HR, 1.01; 95% CI, 1.00-1.03; P=.014) on multivariable analysis. In a comparison of bladder neck with the standard dosimetric variables by use of ROC analysis (prostate V100 >90%, D90 >100%, V150 >60%, urethra D20 >130%), bladder neck D2cc >50% was shown to have the strongest prognostic power for AUT (AUC, 0.697; P<.0001) and LUT (AUC, 0.620; P<.001). Conclusions: Bladder neck D2cc >50% was the strongest predictor for grade ≥2 AUT and LUT in patients treated with LDR brachytherapy. These data support inclusion of bladder neck constraints into brachytherapy planning to decrease urinary toxicity.

  20. Late Urinary Side Effects 10 Years After Low-Dose-Rate Prostate Brachytherapy: Population-Based Results From a Multiphysician Practice Treating With a Standardized Protocol and Uniform Dosimetric Goals

    SciTech Connect

    Keyes, Mira Miller, Stacy; Pickles, Tom; Halperin, Ross; Kwan, Winkle; Lapointe, Vincent; McKenzie, Michael; Spadinger, Ingrid; Pai, Howard; Chan, Elisa K.; Morris, W. James

    2014-11-01

    Purpose: To determine late urinary toxicity (>12 months) in a large cohort of uniformly treated low-dose-rate prostate brachytherapy patients. Methods and Materials: From 1998 to 2009, 2709 patients with National Comprehensive Cancer Network–defined low-risk and low-tier intermediate-risk prostate cancer were treated with Iodine 125 ({sup 125}I) low-dose-rate prostate brachytherapy; 2011 patients with a minimum of 25 months of follow-up were included in the study. Baseline patients, treatment, implant factors, and late urinary toxicity (Radiation Therapy Oncology Group [RTOG] grading system and International Prostate Symptom Score [IPSS]) were recorded prospectively. Time to IPSS resolution, late RTOG genitourinary toxicity was examined with Kaplan-Meier and log-rank tests. Cox proportional hazards regression was done for individual covariates and multivariable models. Results: Median follow-up was 54.5 months (range, 2-13 years). Actuarial toxicity rates reached 27% and 10% (RTOG ≥2 and ≥3, respectively) at 9-13 years. Symptoms resolved quickly in the majority of patients (88% in 6-12 months). The prevalence of RTOG 0, 1, 2, 3, and 4 toxicity with a minimum of 7 years' follow-up was 70%, 21%, 6.4%, 2.3%, and 0.08%, respectively. Patients with a larger prostate volume, higher baseline IPSS, higher D90, acute toxicity, and age >70 years had more late RTOG ≥2 toxicity (all P≤.02). The IPSS resolved slower in patients with lower baseline IPSS and larger ultrasound prostate volume, those not receiving androgen deprivation therapy, and those with higher D90. The crude rate of RTOG 3 toxicity was 6%. Overall the rate of transurethral resection of the prostate was 1.9%; strictures, 2%; incontinence, 1.3%; severe symptoms, 1.8%; late catheterization, 1.3%; and hematuria, 0.8%. The majority (80%) resolved their symptoms in 6-12 months. Conclusion: Long-term urinary toxicity after brachytherapy is low. Although actuarial rates increase with longer follow

  1. Prostate brachytherapy postimplant dosimetry: Automatic plan reconstruction of stranded implants

    SciTech Connect

    Chng, N.; Spadinger, I.; Morris, W. J.; Usmani, N.; Salcudean, S.

    2011-01-15

    Purpose: Plan reconstruction for permanent implant prostate brachytherapy is the process of determining the correspondence between planned and implanted seeds in postimplant analysis. Plan reconstruction informs many areas of brachytherapy quality assurance, including the verification of seed segmentation, misplacement and migration assessment, implant simulations, and the dosimetry of mixed-activity or mixed-species implants. Methods: An algorithm has been developed for stranded implants which uses the interseed spacing constraints imposed by the suture to improve the accuracy of reconstruction. Seventy randomly selected clinical cases with a mean of 23.6 (range 18-30) needles and mean density of 2.0 (range 1.6-2.6) 2.0 (range 1.6-2.6) seeds/cm{sup 3} were automatically reconstructed and the accuracy compared to manual reconstructions performed using a custom 3D graphical interface. Results: Using the automatic algorithm, the mean accuracy of the assignment relative to manual reconstruction was found to be 97.7{+-}0.5%. Fifty-two of the 70 cases (74%) were error-free; of seeds in the remaining cases, 96.7{+-}0.3% were found to be attributed to the correct strand and 97.0{+-}0.3% were correctly connected to their neighbors. Any necessary manual correction using the interface is usually straightforward. For the clinical data set tested, neither the number of seeds or needles, average density, nor the presence of clusters was found to have an effect on reconstruction accuracy using this method. Conclusions: Routine plan reconstruction of stranded implants can be performed with a high degree of accuracy to support postimplant dosimetry and quality analyses.

  2. Prostate CT segmentation method based on nonrigid registration in ultrasound-guided CT-based HDR prostate brachytherapy

    PubMed Central

    Yang, Xiaofeng; Rossi, Peter; Ogunleye, Tomi; Marcus, David M.; Jani, Ashesh B.; Mao, Hui; Curran, Walter J.; Liu, Tian

    2014-01-01

    Purpose: The technological advances in real-time ultrasound image guidance for high-dose-rate (HDR) prostate brachytherapy have placed this treatment modality at the forefront of innovation in cancer radiotherapy. Prostate HDR treatment often involves placing the HDR catheters (needles) into the prostate gland under the transrectal ultrasound (TRUS) guidance, then generating a radiation treatment plan based on CT prostate images, and subsequently delivering high dose of radiation through these catheters. The main challenge for this HDR procedure is to accurately segment the prostate volume in the CT images for the radiation treatment planning. In this study, the authors propose a novel approach that integrates the prostate volume from 3D TRUS images into the treatment planning CT images to provide an accurate prostate delineation for prostate HDR treatment. Methods: The authors’ approach requires acquisition of 3D TRUS prostate images in the operating room right after the HDR catheters are inserted, which takes 1–3 min. These TRUS images are used to create prostate contours. The HDR catheters are reconstructed from the intraoperative TRUS and postoperative CT images, and subsequently used as landmarks for the TRUS–CT image fusion. After TRUS–CT fusion, the TRUS-based prostate volume is deformed to the CT images for treatment planning. This method was first validated with a prostate-phantom study. In addition, a pilot study of ten patients undergoing HDR prostate brachytherapy was conducted to test its clinical feasibility. The accuracy of their approach was assessed through the locations of three implanted fiducial (gold) markers, as well as T2-weighted MR prostate images of patients. Results: For the phantom study, the target registration error (TRE) of gold-markers was 0.41 ± 0.11 mm. For the ten patients, the TRE of gold markers was 1.18 ± 0.26 mm; the prostate volume difference between the authors’ approach and the MRI-based volume was 7.28% ± 0

  3. Prostate CT segmentation method based on nonrigid registration in ultrasound-guided CT-based HDR prostate brachytherapy

    SciTech Connect

    Yang, Xiaofeng Rossi, Peter; Ogunleye, Tomi; Marcus, David M.; Jani, Ashesh B.; Curran, Walter J.; Liu, Tian; Mao, Hui

    2014-11-01

    Purpose: The technological advances in real-time ultrasound image guidance for high-dose-rate (HDR) prostate brachytherapy have placed this treatment modality at the forefront of innovation in cancer radiotherapy. Prostate HDR treatment often involves placing the HDR catheters (needles) into the prostate gland under the transrectal ultrasound (TRUS) guidance, then generating a radiation treatment plan based on CT prostate images, and subsequently delivering high dose of radiation through these catheters. The main challenge for this HDR procedure is to accurately segment the prostate volume in the CT images for the radiation treatment planning. In this study, the authors propose a novel approach that integrates the prostate volume from 3D TRUS images into the treatment planning CT images to provide an accurate prostate delineation for prostate HDR treatment. Methods: The authors’ approach requires acquisition of 3D TRUS prostate images in the operating room right after the HDR catheters are inserted, which takes 1–3 min. These TRUS images are used to create prostate contours. The HDR catheters are reconstructed from the intraoperative TRUS and postoperative CT images, and subsequently used as landmarks for the TRUS–CT image fusion. After TRUS–CT fusion, the TRUS-based prostate volume is deformed to the CT images for treatment planning. This method was first validated with a prostate-phantom study. In addition, a pilot study of ten patients undergoing HDR prostate brachytherapy was conducted to test its clinical feasibility. The accuracy of their approach was assessed through the locations of three implanted fiducial (gold) markers, as well as T2-weighted MR prostate images of patients. Results: For the phantom study, the target registration error (TRE) of gold-markers was 0.41 ± 0.11 mm. For the ten patients, the TRE of gold markers was 1.18 ± 0.26 mm; the prostate volume difference between the authors’ approach and the MRI-based volume was 7.28% ± 0

  4. Temporal relationship between prostate brachytherapy and the diagnosis of colorectal cancer

    SciTech Connect

    Gutman, Sarah A.; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Galbreath, Robert W.; Adamovich, Edward

    2006-09-01

    Purpose: To identify the location of pretreatment and posttreatment colorectal malignancies and posttreatment colorectal polyps in patients with clinically localized prostate cancer managed with brachytherapy. Methods and Materials: From April 1995 through July 2004, 1,351 consecutive patients underwent brachytherapy for clinical stage T1b-T3a (American Joint Committee on Cancer, 2002) prostate cancer. Supplemental external beam radiotherapy (XRT) was administered to 699 patients. The median follow-up was 4.6 years. Operative and pathology reports were reviewed for all patients with pretreatment and posttreatment colorectal cancer and posttreatment colorectal polyps. Multiple parameters were evaluated for the development of colorectal cancer or colorectal polyps. Results: Colorectal cancer was diagnosed in 23 and 25 patients before and after prostate brachytherapy, respectively. No differences were identified in the distribution of colorectal cancers either before or after treatment (3 and 4 rectal cancers in the pre- and postbrachytherapy cohorts). Thirty-five of the 48 colorectal cancers (73%) were diagnosed within 5 years of brachytherapy with a peak incidence 1 year after brachytherapy. One hundred ninety-two colorectal polyps were diagnosed after brachytherapy, 160 (83%) occurred within 4 years of brachytherapy, and only 27 (14%) were located in the rectum. In multivariate Cox regression analysis, prostate D{sub 9} (minimum percentage of the dose covering 90% of the target volume) predicted for posttreatment colorectal cancer. Rectal polyps were most closely related to patient age and percent positive biopsies, whereas sigmoid/colon polyps were best predicted by patient age, planning volume, and supplemental XRT. Conclusions: Colorectal cancer was diagnosed with equal frequency before and after brachytherapy with comparable geographic distributions. In addition, the vast majority of postbrachytherapy colorectal polyps were located beyond the confines of the

  5. Systematic Review of Focal Prostate Brachytherapy and the Future Implementation of Image-Guided Prostate HDR Brachytherapy Using MR-Ultrasound Fusion.

    PubMed

    Peach, M Sean; Trifiletti, Daniel M; Libby, Bruce

    2016-01-01

    Prostate cancer is the most common malignancy found in North American and European men and the second most common cause of cancer related death. Since the practice of PSA screening has become common the disease is most often found early and can have a long indolent course. Current definitive therapy treats the whole gland but has considerable long-term side effects. Focal therapies may be able to target the cancer while decreasing dose to organs at risk. Our objective was to determine if focal prostate brachytherapy could meet target objectives while permitting a decrease in dose to organs at risk in a way that would allow future salvage treatments. Further, we wanted to determine if focal treatment results in less toxicity. Utilizing the Medline repository, dosimetric papers comparing whole gland to partial gland brachytherapy and clinical papers that reported toxicity of focal brachytherapy were selected. A total of 9 dosimetric and 6 clinical papers met these inclusion criteria. Together, these manuscripts suggest that focal brachytherapy may be employed to decrease dose to organs at risk with decreased toxicity. Of current technology, image-guided HDR brachytherapy using MRI registered to transrectal ultrasound offers the flexibility and efficiency to achieve such focal treatments. PMID:27293899

  6. Rectal ulcer: Due to ketoprofen, argon plasma coagulation and prostatic brachytherapy.

    PubMed

    Koessler, Thibaud; Servois, Vincent; Mariani, Pascale; Aubert, Emilie; Cacheux, Wulfran

    2014-12-01

    Prostatic brachytherapy with permanent seed implants is a recent and safe radiation therapy technique associated with radiation-induced digestive disease. Argon plasma coagulation procedure is a validated modality in the management of haemorrhagic radiation proctitis, which is known to occasionally induce chronic rectal ulcers. We report here an original case report of an acute painful rectal ulcer as a consequence of the combination of short-term therapy with non-steroidal anti-inflammatory drugs therapy, prostatic brachytherapy with malposition of seed implants and argon plasma coagulation procedure in a patient with haemorrhagic radiation proctitis. The description of this clinical observation is essential to recommend the discontinuation of non-steroidal anti-inflammatory drugs therapy and the control of the position of seed implants in case of prostatic brachytherapy before argon plasma coagulation for radiation-induced proctitis.

  7. Alternative Dose for Choroidal Melanoma Treated With an Iodine-125 Radioactive Plaque: A Single-Institution Retrospective Study

    SciTech Connect

    Saconn, Paul A.; Gee, Christopher J.; Greven, Craig M.; McCoy, Thomas P.; Ekstrand, Kenneth E.; Greven, Kathryn M.

    2010-11-01

    Purpose: The Collaborative Ocular Melanoma Study (COMS) established iodine-125 plaque brachytherapy as an accepted standard treatment for medium-size choroidal melanoma. In the COMS, the prescription dose was 85 Gy. This is a retrospective review of our outcomes in patients treated with lower doses than those used in the COMS. Methods and Materials: From 1990 to 2004, 62 patients were treated with iodine-125 plaque brachytherapy for choroidal melanoma. COMS eye plaques were used with dose prescribed to the apex of the tumor. The median and average dose rates at the tumor apex were 63.5 cGy/h and 62.7 cGy/h, respectively. The median and average total doses were 63.0 Gy and 62.5 Gy (range, 56-69 Gy), respectively. The median and mean durations of implant were 100.0 hours and 101.1 hours (range, 71-165 hours). Results: Median follow-up time was 58.2 months. The 5-year outcomes including overall survival, disease-free survival, cause-specific survival, local failure, secondary enucleation rate, and visual acuity (VA) <20/200 were estimated using the Kaplan-Meier method. Overall, there were 7 local failures, 4 distant failures, and 10 secondary enucleations (6 due to local failure and 4 due to treatment complications). Univariate analysis was performed to identify significant prognostic factors associated with disease-free survival (baseline VA in tumor eye, tumor shape), cause-specific survival (diabetic retinopathy), local failure (none found), secondary enucleation rate (diabetic retinopathy, basal tumor dimension) and VA <20/200 (diabetic retinopathy, tumor shape, age, retinal detachment, treatment depth, and history of vision-limiting condition). Conclusions: Our survival and local control outcomes are comparable to those of the COMS. However, VA at 5 years seems to be better. Lower doses of radiation could potentially lead to better visual outcomes.

  8. Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

    SciTech Connect

    Zhang, Wen Yan, Zhiping Luo, Jianjun Fang, Zhuting Wu, Linlin Liu, QingXin Qu, Xudong Liu, Lingxiao Wang, Jianhua

    2013-10-15

    Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT

  9. Long-Term Results of an RTOG Phase II Trial (00-19) of External-Beam Radiation Therapy Combined With Permanent Source Brachytherapy for Intermediate-Risk Clinically Localized Adenocarcinoma of the Prostate

    SciTech Connect

    Lawton, Colleen A.; Yan, Yan; Lee, W. Robert; Gillin, Michael; Firat, Selim; Baikadi, Madhava; Crook, Juanita; Kuettel, Michael; Morton, Gerald; Sandler, Howard

    2012-04-01

    Purpose: External-beam radiation therapy combined with low-doserate permanent brachytherapy are commonly used to treat men with localized prostate cancer. This Phase II trial was performed to document late gastrointestinal or genitourinary toxicity as well as biochemical control for this treatment in a multi-institutional cooperative group setting. This report defines the long-term results of this trial. Methods and Materials: All eligible patients received external-beam radiation (45 Gy in 25 fractions) followed 2-6 weeks later by a permanent iodine 125 implant of 108 Gy. Late toxicity was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring scheme. Biochemical control was defined by the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus definition and the ASTRO Phoenix definition. Results: One hundred thirty-eight patients were enrolled from 20 institutions, and 131 were eligible. Median follow-up (living patients) was 8.2 years (range, 2.7-9.3 years). The 8-year estimate of late grade >3 genitourinary and/or gastrointestinal toxicity was 15%. The most common grade >3 toxicities were urinary frequency, dysuria, and proctitis. There were two grade 4 toxicities, both bladder necrosis, and no grade 5 toxicities. In addition, 42% of patients complained of grade 3 impotence (no erections) at 8 years. The 8-year estimate of biochemical failure was 18% and 21% by the Phoenix and ASTRO consensus definitions, respectively. Conclusion: Biochemical control for this treatment seems durable with 8 years of follow-up and is similar to high-dose external beam radiation alone or brachytherapy alone. Late toxicity in this multi-institutional trial is higher than reports from similar cohorts of patients treated with high-dose external-beam radiation alone or permanent low-doserate brachytherapy alone, perhaps suggesting further attention to strategies that limit doses to

  10. Permanent prostate brachytherapy extracapsular radiation dose distributions: analysis of a multi-institutional database

    PubMed Central

    Butler, Wayne M.; Grimm, Peter; Morris, Mallory; Lief, Jonathan H.; Bennett, Abbey; Fiano, Ryan

    2013-01-01

    Purpose Periprostatic brachytherapy doses impact biochemical control. In this study, we evaluate extracapsular volumetric dosimetry following permanent prostate brachytherapy in patients entered in a multi-institutional community database. Material and methods In the database, 4547 patients underwent brachytherapy (3094 – 125I, 1437 – 103Pd and 16 – 131Cs). Using the originally determined prostate volume, a 5 mm, 3-dimensional peri-prostatic anulus was constructed around the prostate (except for a 2 mm posterior margin), and evaluated in its entirety and in 90° segments. Prostate dosimetric parameters consisted of a V100 and D90 while the annular dosimetry was reported as a V100. Results The intraprostatic V100 and D90 for 103Pd, and 125I were statistically comparable when stratified by isotope and/or monotherapy vs. boost. The overall mean V100 for the periprostatic annulus was 62.8%. The mean V100 at the base (51.6%) was substantially less than the apex (73.5%) and midgland (65.9%). In addition, for all patients, the anterior V100 (45.7%) was less than the lateral (68.8%) and the posterior (75.0%). The geometric V100 annular differences were consistent when evaluated by isotope. Overall, the V100 was higher in the 125I cohort. Conclusions The optimal extracapsular brachytherapy dose and radial extent remains unknown, but will prove increasingly important with reductions and/or elimination of supplemental external beam radiation therapy. The large multi-institutional community database demonstrates periprostatic annular doses that are not as robust as those in selected high volume brachytherapy centers, and may be inadequate for optimal biochemical control following monotherapeutic brachytherapy, especially in higher risk patients. PMID:24143144

  11. SU-E-T-397: Include Organ Deformation Into Dose Calculation of Prostate Brachytherapy

    SciTech Connect

    Shao, Y; Shen, D; Chen, R; Wang, A; Lian, J

    2014-06-01

    Purpose: Prostate brachytherapy is an important curative treatment for patients with localized prostate cancer. In brachytherapy, rectal balloon is generally needed to adjust for unfavorable prostate position for seed placement. However, rectal balloon causes prostate deformation, which is not accounted for in dosimetric planning. Therefore, it is possible that brachytherapy dosimetry deviates significantly from initial plan when prostate returns to its non-deformed state (after procedure). The goal of this study is to develop a method to include prostate deformation into the treatment planning of brachytherapy dosimetry. Methods: We prospectively collected ultrasound images of prostate pre- and post- rectal balloon inflation from thirty five consecutive patients undergoing I-125 brachytherapy. Based on the cylinder coordinate systems, we learned the initial coordinate transformation parameters between the manual segmentations of both deformed and non-deformed prostates of each patient in training set. With the nearest-neighbor interpolation, we searched the best transformation between two coordinate systems to maximum the mutual information of deformed and non-deformed images. We then mapped the implanted seeds of five selected patients from the deformed prostate into non-deformed prostate. The seed position is marked on original pre-inflation US image and it is imported into VariSeed software for dose calculation. Results: The accuracy of image registration is 87.5% as quantified by Dice Index. The prostate coverage V100% dropped from 96.5±0.5% of prostate deformed plan to 91.9±2.6% (p<0.05) of non-deformed plan. The rectum V100% decreased from 0.44±0.26 cc to 0.10±0.18 cc (p<0.05). The dosimetry of the urethra showed mild change but not significant: V150% changed from 0.05±0.10 cc to 0.14±0.15 cc (p>0.05) and D1% changed from 212.9±37.3 Gy to 248.4±42.8 Gy (p>0.05). Conclusion: We have developed a deformable image registration method that allows

  12. Determination of the prescription dose for biradionuclide permanent prostate brachytherapy

    SciTech Connect

    Nuttens, V. E.; Lucas, S.

    2008-12-15

    A model based on the linear quadratic model that has been corrected for repopulation, sublethal cell damage repair, and RBE effect has been used to determine the prescription dose for prostate permanent brachytherapy using seeds loaded with a mixture of {sup 103}Pd and {sup 125}I or a mixture of {sup 103}Pd and {sup 131}Cs. The prescription dose was determined by comparing the tumor cell survival fractions between the considered biradionuclide seed implant and one monoradionuclide seed implant chosen from {sup 103}Pd, {sup 125}I, and {sup 131}Cs. Prostate edema is included in the model. The influence of the value of the radiobiological parameters and RBE were also investigated. Two mixtures of radionuclides were considered: {sup 103}Pd{sub 0.75}-{sup 125}I{sub 0.25} and {sup 103}Pd{sub 0.25}-{sup 131}Cs{sub 0.75}, where the subscripts indicate the fractions of total initial internal activity in the biradionuclide seed. These fractions were selected in order to obtain a dose distribution that lies between that of {sup 103}Pd and {sup 125}I/{sup 131}Cs. As expected, the computed prescription dose values are dependent on the model parameters (edema half-life and magnitude, radiobiogical parameters, and RBE). The radionuclide used as a benchmark also has a strong impact on the derived prescribed dose. The large uncertainties in the radiobiological parameters and RBE values produce big errors in the computed prescribed dose. Averaged over the range of all the parameters and depending on the radionuclide used as a benchmark (in subscript), the derived prescription dose for the first mixture (PdI) would be: D{sub Pd}{sup PdI}=142{sub -16}{sup +15} Gy and D{sub I}{sup PdI}=142{sub -8}{sup +6} Gy; and D{sub Pd}{sup PdCs}=128{sub -13}{sup +13} Gy and D{sub Cs}{sup PdCs}=115{sub -7}{sup +6} Gy for the PdCs mixture. The uncertainties could be reduced if the radiobiological parameters and RBE value were known more accurately. However, as edema characteristics are patient

  13. Risk of All-Cause and Prostate Cancer-Specific Mortality After Brachytherapy in Men With Small Prostate Size

    SciTech Connect

    Nguyen, Paul L.; Chen, Ming H.; Choueiri, Toni K.; Hoffman, Karen E.; Hu, Jim C.; Martin, Neil E.; Beard, Clair J.; Dosoretz, Daniel E.; Moran, Brian J.; Katin, Michael J.; Braccioforte, Michelle H.; Ross, Rudi; Salenius, Sharon A.; Kantoff, Philip W.; D'Amico, Anthony V.

    2011-04-01

    Background: Brachytherapy for prostate cancer can be technically challenging in men with small prostates ({<=}20 cc), but it is unknown whether their outcomes are different than those of men with larger prostates. Methods and Materials: We studied 6,416 men treated with brachytherapy in one of 21 community-based practices. Cox regression and Fine and Gray's regression were used to determine whether volume {<=}20 cc was associated with a higher risk of all-cause mortality (ACM) or prostate cancer-specific mortality (PCSM), respectively, after adjustment for other known prognostic factors. Results: 443 patients (6.9%) had a prostate volume {<=}20 cc. After a median follow-up of 2.91 years (interquartile range, 1.06-4.79), volume {<=}20 cc was associated with a significantly higher risk of ACM (adjusted hazard ratio = 1.33 [95% CI 1.08-1.65], p = 0.0085) with 3-year estimates of ACM for {<=}20 cc vs. >20 cc of 13.0% vs. 6.9% (p = 0.028). Only 23 men (0.36%) have died of prostate cancer, and no difference was seen in PCSM by volume (p = 0.4). Conclusion: Men with small prostates at the time of implant had a 33% higher risk of ACM, and the underlying cause of this remains uncertain. No increase in PCSM was observed in men with volume {<=}20cc, suggesting that a small prostate should not in itself be a contraindication for brachytherapy, but inasmuch as absolute rates of PCSM were small, further follow-up will be needed to confirm this finding.

  14. Effect of constipation on dosimetry after permanent seed brachytherapy for prostate cancer

    PubMed Central

    Dolado, M. Carmen; Núñez, Eduardo J.; Otón, Claudio A.

    2015-01-01

    Purpose A major concern in prostate brachytherapy is rectal toxicity, which mainly depends on the dose and volume of rectum involved by radiation. We hypothesize that the rectal distension, as produced by constipation, influences the dosimetric parameters of the rectum and other pelvic organs. Material and methods An open, controlled, prospective, paired trial (pre-post test) was designed and conducted. Twenty-three patients treated with prostate brachytherapy were recruited, of which 21 were evaluated. All of them underwent two CT scans, the first one with empty rectum and the second with rectum distended by a catheter balloon. Target volumes and organs at risk were delineated, and dosimetric parameters were calculated and then compared for each patient between both CT. Results For rectum, D2cc increased 15.8% (p < 0.001) and D0.1cc 24.05% (p = 0.002) when the rectum was full. A significant difference was also found in dose distribution to prostate, when rectum is distended, a 1% decrease in V100 (p = 0.031) and a 3.25% in D90 (p = 0.033) was registered. Conclusions The status of rectal distension, as occurs in constipation, has a deleterious influence on prostate brachytherapy dosimetry. This situation increases the radiation to rectum and modifies dose distribution to prostate. We recommend prevention of constipation for at least two half lives of the radioactive seeds. PMID:26622226

  15. Plastic optical fibre sensor for in-vivo radiation monitoring during brachytherapy

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; Lewis, E.; O'Keeffe, S.

    2015-09-01

    An optical fibre sensor is presented for applications in real-time in-vivo monitoring of the radiation dose a cancer patient receives during seed implantation in Brachytherapy. The sensor is based on radioluminescence whereby radiation sensitive scintillation material is embedded in the core of a 1mm plastic optical fibre. Three scintillation materials are investigated: thallium-doped caesium iodide (CsI:Tl), terbium-doped gadolinium oxysulphide (Gd2O2S:Tb) and europium-doped lanthanum oxysulphide (La2O2S:Eu). Terbium-doped gadolinium oxysulphide was identified as being the most suitable scintillator and further testing demonstrates its measureable response to different activities of Iodine-125, the radio-active source commonly used in Brachytherapy for treating prostate cancer.

  16. SU-E-T-259: Particle Swarm Optimization in Radial Dose Function Fitting for a Novel Iodine-125 Seed

    SciTech Connect

    Wu, X; Duan, J; Popple, R; Huang, M; Shen, S; Brezovich, I; Cardan, R; Benhabib, S

    2014-06-01

    Purpose: To determine the coefficients of bi- and tri-exponential functions for the best fit of radial dose functions of the new iodine brachytherapy source: Iodine-125 Seed AgX-100. Methods: The particle swarm optimization (PSO) method was used to search for the coefficients of the biand tri-exponential functions that yield the best fit to data published for a few selected radial distances from the source. The coefficients were encoded into particles, and these particles move through the search space by following their local and global best-known positions. In each generation, particles were evaluated through their fitness function and their positions were changed through their velocities. This procedure was repeated until the convergence criterion was met or the maximum generation was reached. All best particles were found in less than 1,500 generations. Results: For the I-125 seed AgX-100 considered as a point source, the maximum deviation from the published data is less than 2.9% for bi-exponential fitting function and 0.2% for tri-exponential fitting function. For its line source, the maximum deviation is less than 1.1% for bi-exponential fitting function and 0.08% for tri-exponential fitting function. Conclusion: PSO is a powerful method in searching coefficients for bi-exponential and tri-exponential fitting functions. The bi- and tri-exponential models of Iodine-125 seed AgX-100 point and line sources obtained with PSO optimization provide accurate analytical forms of the radial dose function. The tri-exponential fitting function is more accurate than the bi-exponential function.

  17. Brachytherapy in the therapy of prostate cancer – an interesting choice

    PubMed Central

    2013-01-01

    Brachytherapy is a curative alternative to radical prostatectomy or external beam radiation [i.e. 3D conformal external beam radiation therapy (CRT), intensity-modulated radiation therapy (IMRT)] with comparable long-term survival and biochemical control and the most favorable toxicity. HDR brachytherapy (HDR-BT) in treatment of prostate cancer is most frequently used together with external beam radiation therapy (EBRT) as a boost (increasing the treatment dose precisely to the tumor). In the early stages of the disease (low, sometimes intermediate risk group), HDR-BT is more often used as monotherapy. There are no significant differences in treatment results (overall survival rate – OS, local recurrence rate – LC) between radical prostatectomy, EBRT and HDR-BT. Low-dose-rate brachytherapy (LDR-BT) is a radiation method that has been known for several years in treatment of localized prostate cancer. The LDR-BT is applied as a monotherapy and also used along with EBRT as a boost. It is used as a sole radical treatment modality, but not as a palliative treatment. The use of brachytherapy as monotherapy in treatment of prostate cancer enables many patients to keep their sexual functions in order and causes a lower rate of urinary incontinence. Due to progress in medical and technical knowledge in brachytherapy (“real-time” computer planning systems, new radioisotopes and remote afterloading systems), it has been possible to make treatment time significantly shorter in comparison with other methods. This also enables better protection of healthy organs in the pelvis. The aim of this publication is to describe both brachytherapy methods. PMID:24596528

  18. Long-Term Results of a Prospective, Phase II Study of Long-Term Androgen Ablation, Pelvic Radiotherapy, Brachytherapy Boost, and Adjuvant Docetaxel in Patients With High-Risk Prostate Cancer

    SciTech Connect

    DiBiase, Steven J.; Hussain, Arif; Kataria, Ritesh; Amin, Pradip; Bassi, Sunakshi; Dawson, Nancy; Kwok, Young

    2011-11-01

    Purpose: We report the long-term results of a prospective, Phase II study of long-term androgen deprivation (AD), pelvic radiotherapy (EBRT), permanent transperineal prostate brachytherapy boost (PB), and adjuvant docetaxel in patients with high-risk prostate cancer. Methods and Materials: Eligibility included biopsy-proven prostate adenocarcinoma with the following: prostate-specific antigen (PSA) > 20 ng/ml; or Gleason score of 7 and a PSA >10 ng/ml; or any Gleason score of 8 to 10; or stage T2b to T3 irrespective of Gleason score or PSA. Treatment consisted of 45 Gy of pelvic EBRT, followed 1 month later by PB with either iodine-125 or Pd-103. One month after PB, patients received three cycles of docetaxel chemotherapy (35 mg/m{sup 2} per week, Days 1, 8, and 15 every 28 days). All patients received 2 years of AD. Biochemical failure was defined as per the Phoenix definition (PSA nadir + 2). Results: From August 2000 to March 2004, 42 patients were enrolled. The median overall and active follow-ups were 5.6 years (range, 0.9-7.8 years) and 6.3 years (range, 4-7.8 years), respectively. Grade 2 and 3 acute genitourinary (GU) and gastrointestinal (GI) toxicities were 50.0% and 14.2%, respectively, with no Grade 4 toxicities noted. Grade 3 and 4 acute hematologic toxicities were 19% and 2.4%, respectively. Of the patients, 85.7% were able to complete the planned multimodality treatment. The 5- and 7-year actuarial freedom from biochemical failures rates were 89.6% and 86.5%, and corresponding rates for disease-free survival were 76.2% and 70.4%, respectively. The 5- and 7-year actuarial overall survival rates were 83.3% and 80.1%, respectively. The 5- and 7-year actuarial rates of late Grade 2 GI/GU toxicity (no Grade 3-5) was 7.7%. Conclusions: The trimodality approach of using 2 years of AD, external radiation, brachytherapy, and upfront docetaxel in high-risk prostate cancer is well tolerated, produces encouraging long-term results, and should be validated in a

  19. Focal partial salvage low-dose-rate brachytherapy for local recurrent prostate cancer after permanent prostate brachytherapy with a review of the literature

    PubMed Central

    Wakumoto, Yoshiaki; Yamaguchi, Nanae; Horie, Shigeo; Sasai, Keisuke

    2016-01-01

    Purpose To investigate the treatment results for focal partial salvage re-implantation against local recurrence after permanent prostate brachytherapy. Material and methods Between January 2010 and September 2015, 12 patients were treated with focal partial salvage re-implantation for local recurrence after low-dose-rate brachytherapy using 125I seeds. The focal clinical target volume (F-CTV) was delineated on positive biopsy areas in a mapping biopsy, combining the cold spots on the post-implant dosimetry for initial brachytherapy. The F-CTV was expanded by 3 mm to create the planning target volume (PTV) as a margin to compensate for uncertainties in image registration and treatment delivery. The prescribed dose to the PTV was 145 Gy. The characteristics and biochemical disease-free survival (BdFS) rates were analyzed. Genitourinary (GU) and gastrointestinal (GI) toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 4. Results The median prostate-specific antigen (PSA) level at re-implantation was 4.09 ng/ml (range: 2.91-8.24 ng/ml). The median follow-up time was 56 months (range: 6-74 months). The median RD2cc and UD10 were 63 Gy and 159 Gy, respectively. The 4-year BdFS rate was 78%, which included non-responders. Biochemical recurrence occurred in two patients after 7 and 31 months, respectively. The former was treated with hormonal therapy after biochemical failure, and the latter underwent watchful waiting (PSA at the last follow-up of 53 months: 7.3 ng/ml) at the patient's request. No patients had grade 3 GU/GI toxicities or died after salvage re-implantation. Conclusions The partial salvage low-dose-rate brachytherapy used to treat local recurrence after permanent prostate brachytherapy is well-tolerated, with high biochemical response rates. This treatment can be not only a method to delay chemical castration but also a curative treatment option in cases of local recurrence of prostate carcinoma after seed implantation

  20. Automatic segmentation of radiographic fiducial and seeds from X-ray images in prostate brachytherapy

    PubMed Central

    Kuo, Nathanael; Deguet, Anton; Song, Danny Y.; Burdette, Everette C.; Prince, Jerry L.; Lee, Junghoon

    2011-01-01

    Prostate brachytherapy guided by transrectal ultrasound is a common treatment option for early stage prostate cancer. Prostate cancer accounts for 28% of cancer cases and 11% of cancer deaths in men with 217,730 estimated new cases and 32,050 estimated deaths in 2010 in the United States alone. The major current limitation is the inability to reliably localize implanted radiation seeds spatially in relation to the prostate. Multimodality approaches that incorporate X-ray for seed localization have been proposed, but they require both accurate tracking of the imaging device and segmentation of the seeds. Some use image-based radiographic fiducials to track the X-ray device, but manual intervention is needed to select proper regions of interest for segmenting both the tracking fiducial and the seeds, to evaluate the segmentation results, and to correct the segmentations in the case of segmentation failure, thus requiring a significant amount of extra time in the operating room. In this paper, we present an automatic segmentation algorithm that simultaneously segments the tracking fiducial and brachytherapy seeds, thereby minimizing the need for manual intervention. In addition, through the innovative use of image processing techniques such as mathematical morphology, Hough transforms, and RANSAC, our method can detect and separate overlapping seeds that are common in brachytherapy implant images. Our algorithm was validated on 55 phantom and 206 patient images, successfully segmenting both the fiducial and seeds with a mean seed segmentation rate of 96% and sub-millimeter accuracy. PMID:21802975

  1. Stratification of brachytherapy-treated intermediate-risk prostate cancer patients into favorable and unfavorable cohorts

    PubMed Central

    Butler, Wayne M.; Galbreath, Robert W.; Fiano, Ryan; Adamovich, Edward

    2015-01-01

    Purpose To evaluate biochemical failure (BF) and prostate cancer specific mortality (PCSM) in intermediate-risk (IR) brachytherapy patients stratified into favorable and unfavorable cohorts, and to compare those outcomes to patients with low (LR) and high-risk (HR) disease. Material and methods From March 1995 till February 2012, 2,502 consecutive patients underwent permanent interstitial brachytherapy for clinically localized prostate cancer. Patients were stratified into risk groups as per the NCCN guidelines with further stratification of the intermediate risk cohort into unfavorable (primary Gleason pattern 4, ≥ 50% positive biopsies or ≥ 2 IR features) and favorable cohorts. Median follow-up was 8.5 years. The brachytherapy prescription dose was prescribed to the prostate gland with generous periprostatic margins. Biochemical failure was defined as a PSA > 0.40 ng/ml after nadir. Patients with metastatic prostate cancer or non-metastatic castrate resistant disease who died of any cause were classified as dead of prostate cancer. Multiple parameters were evaluated for effect on outcomes. Results Fifteen year BF for LR, favorable IR, unfavorable IR, and HR were 1.4%, 2.2%, 7.1%, and 11.1% (p < 0.001), respectively. At 15 years, PCSM for LR, favorable IR, unfavorable IR, and HR was 0.3%, 0.6%, 2.2% and 4.6% (p < 0.001), respectively. In multivariate analysis, BF was best predicted by risk group, pre-implant PSA, percent positive biopsies, prostate volume, and ADT duration, while PCSM was most closely related to risk group, percent positive biopsies and prostate volume. Conclusions Patients with favorable IR disease have biochemical and PCSM outcomes comparable to those of patients with LR disease. Although unfavorable IR has greater than a 3-fold increased risk of BF and PCSM when compared to favorable IR, the outcomes remain superior to those men with HR disease. PMID:26816337

  2. PSA Bounce and Biochemical Failure After Brachytherapy for Prostate Cancer: A Study of 820 Patients With a Minimum of 3 Years of Follow-Up

    SciTech Connect

    Caloglu, Murat; Ciezki, Jay P.; Reddy, Chandana A.; Angermeier, Kenneth; Ulchaker, James; Chehade, Nabil; Altman, Andrew; Magi-Galuzzi, Christina; Klein, Eric A.

    2011-07-01

    Purpose: To determine clinical or dosimetric factors associated with a prostate-specific antigen (PSA) bounce, as well as an association between a PSA bounce and biochemical relapse-free survival (bRFS), in patients treated with iodine-125 brachytherapy. Methods and Materials: A variety of clinical and treatment factors were examined in 820 patients who had a minimum of 3 years of PSA follow-up with T1-T2cN0M0 prostate cancer. Four different PSA threshold values were used for defining a PSA bounce: a PSA rise of {>=}0.2, {>=}0.4, {>=}0.6, and {>=}0.8 ng/mL. Results: A PSA bounce of {>=}0.2, {>=}0.4, {>=}0.6, and {>=}0.8 ng/mL was noted in 247 patients (30.1%), 161 (19.6%), 105 (12.8%), and 78 (9.5%), respectively. The median time to the first PSA rise was 17.4, 16.25, 16.23, and 15.71 months, respectively, vs. 34.35 months for a biochemical failure (p < 0.0001). A PSA rise of {>=}0.2 ng/mL was the only definition for which there was a significant difference in bRFS between bounce and non-bounce patients. The 5-year bRFS rate of patients having a PSA bounce of {>=}0.2 was 97.7% vs. 91% for those who did not have a PSA bounce (p = 0.0011). On univariate analysis for biochemical failure, age, risk group, and PSAs per year had a statistically significant correlation with PSA bounce of {>=}0.2 ng/mL. On multivariate analysis, age and PSAs per year remained statistically significant (p < 0.0001 and p = 0.0456, respectively). Conclusions: A bounce definition of a rise {>=}0.2 ng/mL is a reliable definition among several other definitions. The time to first PSA rise is the most valuable factor for distinguishing between a bounce and biochemical failure.

  3. Source strength assay of iodine-125 seeds sealed within sterile packaging.

    PubMed

    Otani, Yuki; Yamada, Takahiro; Kato, Shingo; Shikama, Naoto; Funakoshi, Kazuto; Kuroda, Isao; Numasaki, Hodaka; Nose, Takayuki; Dokiya, Takushi; Oguchi, Masahiko

    2013-01-01

    Early-stage prostate cancer is widely treated by iodine-125 (I-125) seed implantation. While quality assurance methods are in place to assure consistency in I-125 seed source strength, current methods involve the breaking of the sterilization package, raising issues concerning sterility and time limitations. The purpose of this study was to develop a method of characterizing the total source strength of I-125 seeds within a cartridge that has been sealed within a sterilization package and to evaluate the probability of detecting an out-of-calibration seed (aberrant seed). We defined a protocol to determine the ability of a well-type ionization chamber to detect aberrant I-125 seeds within a cartridge sealed in the sterilization package. A novel jig for a well-type ionization chamber was designed to accommodate the sterilization package. One seed was chosen randomly from two cartridges containing five or 15 seeds (0.544 U source strength) and was exchanged with aberrant seeds of six different source strengths. The source strength was measured at each position within the cartridge. The results indicated that the response of the well chamber was sensitive to changes in the aberrant seed position within the cartridge and the source strength of the aberrant seed. The correlation coefficient between single seed and batch assay results was high (0.998). A novel jig and a measurement method using a well ionization chamber were developed, which allowed for a batch assay characterization of the total source strength of I-125 seeds within a cartridge sealed within sterilization package. This method is simple, time-saving, and offers greater practical application. PMID:23470939

  4. Effect of edema, relative biological effectiveness, and dose heterogeneity on prostate brachytherapy

    SciTech Connect

    Wang, Jian Z.; Mayr, Nina A.; Nag, Subir; Montebello, Joseph; Gupta, Nilendu; Samsami, Nina; Kanellitsas, Christos

    2006-04-15

    Many factors influence response in low-dose-rate (LDR) brachytherapy of prostate cancer. Among them, edema, relative biological effectiveness (RBE), and dose heterogeneity have not been fully modeled previously. In this work, the generalized linear-quadratic (LQ) model, extended to account for the effects of edema, RBE, and dose heterogeneity, was used to assess these factors and their combination effect. Published clinical data have shown that prostate edema after seed implant has a magnitude (ratio of post- to preimplant volume) of 1.3-2.0 and resolves exponentially with a half-life of 4-25 days over the duration of the implant dose delivery. Based on these parameters and a representative dose-volume histogram (DVH), we investigated the influence of edema on the implant dose distribution. The LQ parameters ({alpha}=0.15 Gy{sup -1} and {alpha}/{beta}=3.1 Gy) determined in earlier studies were used to calculate the equivalent uniform dose in 2 Gy fractions (EUD{sub 2}) with respect to three effects: edema, RBE, and dose heterogeneity for {sup 125}I and {sup 103}Pd implants. The EUD{sub 2} analysis shows a negative effect of edema and dose heterogeneity on tumor cell killing because the prostate edema degrades the dose coverage to tumor target. For the representative DVH, the V{sub 100} (volume covered by 100% of prescription dose) decreases from 93% to 91% and 86%, and the D{sub 90} (dose covering 90% of target volume) decrease from 107% to 102% and 94% of prescription dose for {sup 125}I and {sup 103}Pd implants, respectively. Conversely, the RBE effect of LDR brachytherapy [versus external-beam radiotherapy (EBRT) and high-dose-rate (HDR) brachytherapy] enhances dose effect on tumor cell kill. In order to balance the negative effects of edema and dose heterogeneity, the RBE of prostate brachytherapy was determined to be approximately 1.2-1.4 for {sup 125}I and 1.3-1.6 for {sup 103}Pd implants. These RBE values are consistent with the RBE data published in the

  5. Seed Implant Retention Score Predicts the Risk of Prolonged Urinary Retention After Prostate Brachytherapy

    SciTech Connect

    Lee, Hoon K.; Adams, Marc T.; Shi, Qiuhu; Basillote, Jay; LaMonica, Joanne; Miranda, Luis; Motta, Joseph

    2010-04-15

    Purpose: To risk-stratify patients for urinary retention after prostate brachytherapy according to a novel seed implant retention score (SIRS). Patients and Methods: A total of 835 patients underwent transperineal prostate seed implant from March 1993 to January 2007; 197 patients had {sup 125}I and 638 patients had {sup 103}Pd brachytherapy. Four hundred ninety-four patients had supplemental external-beam radiation. The final downsized prostate volume was used for the 424 patients who had neoadjuvant hormone therapy. Retention was defined as reinsertion of a Foley catheter after the implant. Results: Retention developed in 7.4% of patients, with an average duration of 6.7 weeks. On univariate analysis, implant without supplemental external-beam radiation (10% vs. 5.6%; p = 0.02), neoadjuvant hormone therapy (9.4% vs. 5.4%; p = 0.02), baseline alpha-blocker use (12.5% vs. 6.3%; p = 0.008), and increased prostate volume (13.4% vs. 6.9% vs. 2.9%, >45 cm{sup 3}, 25-45 cm{sup 3}, <25 cm{sup 3}; p = 0.0008) were significantly correlated with increased rates of retention. On multivariate analysis, implant without supplemental external-beam radiation, neoadjuvant hormone therapy, baseline alpha-blocker use, and increased prostate volume were correlated with retention. A novel SIRS was modeled as the combined score of these factors, ranging from 0 to 5. There was a significant correlation between the SIRS and retention (p < 0.0001). The rates of retention were 0, 4%, 5.6%, 9%, 20.9%, and 36.4% for SIRS of 0 to 5, respectively. Conclusions: The SIRS may identify patients who are at high risk for prolonged retention after prostate brachytherapy. A prospective validation study of the SIRS is planned.

  6. Workflow modeling and analysis of computer guided prostate brachytherapy under MR imaging control.

    PubMed

    Dickhaus, Christoph F; Burghart, Catherina; Tempany, Clare; D'Amico, Anthony; Haker, Steven; Kikinis, Ron; Woern, Heinz

    2004-01-01

    We demonstrate that classical Business Process Reengineering (BPR) methods can be successfully applied to Computer Aided Surgery while increasing safety and efficiency of the overall procedure through an integrated Workflow Management System. Computer guided Prostate Brachytherapy, as a sophisticated treatment by an interdisciplinary team, is perfectly suited to apply our method. Detailed suggestions for improvement of the whole procedure could be derived by our modified BPR method. PMID:15544246

  7. A fully actuated robotic assistant for MRI-guided prostate biopsy and brachytherapy

    NASA Astrophysics Data System (ADS)

    Li, Gang; Su, Hao; Shang, Weijian; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M.; Fischer, Gregory S.

    2013-03-01

    Intra-operative medical imaging enables incorporation of human experience and intelligence in a controlled, closed-loop fashion. Magnetic resonance imaging (MRI) is an ideal modality for surgical guidance of diagnostic and therapeutic procedures, with its ability to perform high resolution, real-time, high soft tissue contrast imaging without ionizing radiation. However, for most current image-guided approaches only static pre-operative images are accessible for guidance, which are unable to provide updated information during a surgical procedure. The high magnetic field, electrical interference, and limited access of closed-bore MRI render great challenges to developing robotic systems that can perform inside a diagnostic high-field MRI while obtaining interactively updated MR images. To overcome these limitations, we are developing a piezoelectrically actuated robotic assistant for actuated percutaneous prostate interventions under real-time MRI guidance. Utilizing a modular design, the system enables coherent and straight forward workflow for various percutaneous interventions, including prostate biopsy sampling and brachytherapy seed placement, using various needle driver configurations. The unified workflow compromises: 1) system hardware and software initialization, 2) fiducial frame registration, 3) target selection and motion planning, 4) moving to the target and performing the intervention (e.g. taking a biopsy sample) under live imaging, and 5) visualization and verification. Phantom experiments of prostate biopsy and brachytherapy were executed under MRI-guidance to evaluate the feasibility of the workflow. The robot successfully performed fully actuated biopsy sampling and delivery of simulated brachytherapy seeds under live MR imaging, as well as precise delivery of a prostate brachytherapy seed distribution with an RMS accuracy of 0.98mm.

  8. Dose reduction in LDR brachytherapy by implanted prostate gold fiducial markers

    SciTech Connect

    Landry, Guillaume; Reniers, Brigitte; Lutgens, Ludy; Murrer, Lars; Afsharpour, Hossein; Haas-Kock, Danielle de; Visser, Peter; Gils, Francis van; Verhaegen, Frank

    2012-03-15

    Purpose: The dosimetric impact of gold fiducial markers (FM) implanted prior to external beam radiotherapy of prostate cancer on low dose rate (LDR) brachytherapy seed implants performed in the context of combined therapy was investigated. Methods: A virtual water phantom was designed containing a single FM. Single and multi source scenarios were investigated by performing Monte Carlo dose calculations, along with the influence of varying orientation and distance of the FM with respect to the sources. Three prostate cancer patients treated with LDR brachytherapy for a recurrence following external beam radiotherapy with implanted FM were studied as surrogate cases to combined therapy. FM and brachytherapy seeds were identified on post implant CT scans and Monte Carlo dose calculations were performed with and without FM. The dosimetric impact of the FM was evaluated by quantifying the amplitude of dose shadows and the volume of cold spots. D{sub 90} was reported based on the post implant CT prostate contour. Results: Large shadows are observed in the single source-FM scenarios. As expected from geometric considerations, the shadows are dependent on source-FM distance and orientation. Large dose reductions are observed at the distal side of FM, while at the proximal side a dose enhancement is observed. In multisource scenarios, the importance of shadows appears mitigated, although FM at the periphery of the seed distribution caused underdosage (prostate contour, cold spots (<95% prescription dose) of the order of 20 mm{sup 3} were observed. D{sub 90} proved insensitive to the presence of FM for the cases selected. Conclusions: There is a major local impact of FM present in LDR brachytherapy seed implant dose distributions. Therefore, reduced tumor control could be expected from FM implanted in tumors, although

  9. Migration of a strand of four seeds in low-dose-rate brachytherapy

    PubMed Central

    Dedic-Hagan, Jasmina; Teh, Amy Y M; Liang, Eisen; Collett, Nicholas; Woo, Henry H

    2014-01-01

    We report a case of stranded-seed migration (one strand of four seeds), via the prostatic venous plexus to the internal pudendal vein, in low-dose-rate (LDR) prostate brachytherapy. A 70-year-old man with low-risk prostate adenocarcinoma underwent transperineal permanent seed implantation. A total of 93 iodine-125 seeds were implanted (91 stranded seeds and 2 loose seeds). Immediate postimplantation fluoroscopic image and day 1 postimplantation CT scan indicated all implanted seeds to be within the vicinity of the prostate as planned. Day 30 pelvic X-ray and CT scan revealed migration of a strand of four seeds to the right pelvis (adjacent to ischial spine). At 2 years postimplantation, the patient continues to have good disease control with prostate specific antigen level of 0.69 μg/L, and asymptomatic. To the best of our knowledge, this is the first report of migration of an entire strand of seeds following LDR prostate brachytherapy. PMID:24879735

  10. Decline in urinary retention incidence in 805 patients after prostate brachytherapy: The effect of learning curve?

    SciTech Connect

    Keyes, Mira . E-mail: mkeyes@bccancer.bc.ca; Schellenberg, Devin; Moravan, Veronika M.Sc.; McKenzie, Michael; Agranovich, Alexander; Pickles, Tom; Wu, Jonn; Liu, Mitchell; Bucci, Joseph M.B.B.S.; Morris, W. James

    2006-03-01

    Purpose: To evaluate the incidence and factors predictive of acute urinary retention (AUR) in 805 consecutive patients treated with prostate brachytherapy monotherapy and to examine the possible effect of a learning curve. Methods and Materials: Between July 1998 and November 2002, 805 patients were treated with prostate brachytherapy. Low-risk patients (Gleason Score (GS) {<=}6; prostate specific antigen (PSA) {<=}10, and {<=} T2b [UICC 1997]) received implant alone. Patients with prostate volume of 50 cc or more, GS = 7, or PSA = 10 to 15 received 6 months of androgen suppression (AS) with brachytherapy. Patient, treatment, and dosimetric factors examined include baseline prostate symptom score (IPSS), diabetes, vascular disease, PSA, Gleason score, clinical stage, AS, ultrasound planning target volume (PUTV), postimplant prostate volume (obtained with 'Day 30' postimplant CT), CT:PUTV ratio (surrogate for postimplant edema), number of seeds, number of needles, number of seeds per needle, dosimetric parameters (V100, V150, and D90), date of implant (learning curve), and implanting oncologists. Univariate and multivariate analyses were carried out. Results: Acute urinary retention in the first 200 patients was 17% vs. 6.3% in the most recently treated 200 patients (p = 0.002). Overall AUR was 12.7%, and prolonged urinary obstruction incidence (>20 days) was 5%. On multivariate analysis, factors predictive of any AUR include baseline IPSS (p = < 0.004), CT:PUTV ratio (p = < 0.001), PUTV (p = < 0.001), and implant order (learning curve) (p = 0.001). Factors predictive for 'prolonged' catheterization (>20 days) on multivariate analysis include IPSS (p < 0.01), number of needles (p < 0.001), diabetes mellitus (p = 0.048), and CT:PUTV ratio (p < 0.001) Conclusion: Over the years, our AUR rate has fallen significantly (from 17% to 6.3%). On multivariate analysis, highly significant factors include IPSS, PUTV, CT:PUTV ratio (i.e., degree of prostate edema), and order of

  11. Fast prostate segmentation for brachytherapy based on joint fusion of images and labels

    NASA Astrophysics Data System (ADS)

    Nouranian, Saman; Ramezani, Mahdi; Mahdavi, S. Sara; Spadinger, Ingrid; Morris, William J.; Salcudean, Septimiu E.; Abolmaesumi, Purang

    2014-03-01

    Brachytherapy as one of the treatment methods for prostate cancer takes place by implantation of radioactive seeds inside the gland. The standard of care for this treatment procedure is to acquire transrectal ultrasound images of the prostate which are segmented in order to plan the appropriate seed placement. The segmentation process is usually performed either manually or semi-automatically and is associated with subjective errors because the prostate visibility is limited in ultrasound images. The current segmentation process also limits the possibility of intra-operative delineation of the prostate to perform real-time dosimetry. In this paper, we propose a computationally inexpensive and fully automatic segmentation approach that takes advantage of previously segmented images to form a joint space of images and their segmentations. We utilize joint Independent Component Analysis method to generate a model which is further employed to produce a probability map of the target segmentation. We evaluate this approach on the transrectal ultrasound volume images of 60 patients using a leave-one-out cross-validation approach. The results are compared with the manually segmented prostate contours that were used by clinicians to plan brachytherapy procedures. We show that the proposed approach is fast with comparable accuracy and precision to those found in previous studies on TRUS segmentation.

  12. Multi-atlas-based automatic 3D segmentation for prostate brachytherapy in transrectal ultrasound images

    NASA Astrophysics Data System (ADS)

    Nouranian, Saman; Mahdavi, S. Sara; Spadinger, Ingrid; Morris, William J.; Salcudean, S. E.; Abolmaesumi, P.

    2013-03-01

    One of the commonly used treatment methods for early-stage prostate cancer is brachytherapy. The standard of care for planning this procedure is segmentation of contours from transrectal ultrasound (TRUS) images, which closely follow the prostate boundary. This process is currently performed either manually or using semi-automatic techniques. This paper introduces a fully automatic segmentation algorithm which uses a priori knowledge of contours in a reference data set of TRUS volumes. A non-parametric deformable registration method is employed to transform the atlas prostate contours to a target image coordinates. All atlas images are sorted based on their registration results and the highest ranked registration results are selected for decision fusion. A Simultaneous Truth and Performance Level Estimation algorithm is utilized to fuse labels from registered atlases and produce a segmented target volume. In this experiment, 50 patient TRUS volumes are obtained and a leave-one-out study on TRUS volumes is reported. We also compare our results with a state-of-the-art semi-automatic prostate segmentation method that has been clinically used for planning prostate brachytherapy procedures and we show comparable accuracy and precision within clinically acceptable runtime.

  13. Brachytherapy

    MedlinePlus

    ... smaller area in less time than conventional external beam radiation therapy. Brachytherapy is used to treat cancers ... to kill cancer cells and shrink tumors. External beam radiation therapy (EBRT) involves high-energy x-ray ...

  14. Recurrent primary lumbar vertebra chondrosarcoma: Marginal resection and Iodine-125 seed therapy

    PubMed Central

    Ren, Chunpeng; Zeng, Jiancheng; Song, Yueming; Wang, Xiandi

    2014-01-01

    Chondrosarcomas are uncommon in the spinal column. En bloc excisions with wide margins are of critical importance but not always feasible in spine. We report the outcome in a case of recurrent lumbar vertebral chondrosarcoma treated with marginal resection and iodine-125 seeds placed in the resected tumor bed. PMID:24741146

  15. Impact of short course hormonal therapy on overall and cancer specific survival after permanent prostate brachytherapy

    SciTech Connect

    Beyer, David C. . E-mail: dbeyer@azoncology.com; McKeough, Timothy; Thomas, Theresa

    2005-04-01

    Purpose: To review the impact of prior hormonal therapy on 10-year overall and prostate cancer specific survival after primary brachytherapy. Methods and Materials: A retrospective review was performed on the Arizona Oncology Services tumor registry for 2,378 consecutive permanent prostate brachytherapy cases from 1988 through 2001. Hormonal therapy was administered before the implant in 464 patients for downsizing of the prostate or at the discretion of the referring physician. All deceased patients with known clinical recurrence were considered to have died of prostate cancer, irrespective of the immediate cause of death. Risk groups were defined, with 1,135 favorable (prostate-specific antigen [PSA] < 10, Gleason < 7, Stage T1-T2a), 787 intermediate (single adverse feature), and 456 unfavorable (two or more adverse features) patients. Kaplan-Meier actuarial survival curves were generated for both overall and cause-specific survival from the time of treatment. Multivariate analysis was performed to assess the impact of hormonal intervention in comparison with known risk factors of grade, PSA, and age. Results: With follow-up ranging up to 12.6 years and a median of 4.1 year, a total of 474 patients died, with 67 recorded as due to prostate cancer. Overall and cause-specific 10-year survival rates are 43% and 88%, respectively. Overall survival is 44% for the hormone naive patients, compared with 20% for the hormone-treated cohort (p = 0.02). The cancer-specific survival is 89% vs. 81% for the same groups (p = 0.133). Multivariate analysis confirms the significance of age > 70 years (p = 0.0013), Gleason score {>=} 7 (p = 0.0005), and prior hormone use (p = 0.0065) on overall survival. Conclusions: At 10 years, in prostate cancer patients receiving brachytherapy, overall survival is worse in men receiving neoadjuvant hormonal therapy, compared with hormone naive patients. This does not appear to be due to other known risk factors for survival (i.e., stage, grade

  16. Low-dose-rate brachytherapy for patients with transurethral resection before implantation in prostate cancer. Long-term results

    PubMed Central

    Prada, Pedro J.; Anchuelo, Javier; Blanco, Ana García; Payá, Gema; Cardenal, Juan; Acuña, Enrique; Ferri, María; Vázquez, Andrés; Pacheco, Maite; Sanchez, Jesica

    2016-01-01

    ABSTRACT Objectives We analyzed the long-term oncologic outcome for patients with prostate cancer and transurethral resection who were treated using low-dose-rate (LDR) prostate brachytherapy. Methods and Materials From January 2001 to December 2005, 57 consecutive patients were treated with clinically localized prostate cancer. No patients received external beam radiation. All of them underwent LDR prostate brachytherapy. Biochemical failure was defined according to the “Phoenix consensus”. Patients were stratified as low and intermediate risk based on The Memorial Sloan Kettering group definition. Results The median follow-up time for these 57 patients was 104 months. The overall survival according to Kaplan-Meier estimates was 88% (±6%) at 5 years and 77% (±6%) at 12 years. The 5 and 10 years for failure in tumour-free survival (TFS) was 96% and respectively (±2%), whereas for biochemical control was 94% and respectively (±3%) at 5 and 10 years, 98% (±1%) of patients being free of local recurrence. A patient reported incontinence after treatment (1.7%). The chronic genitourinary complains grade I were 7% and grade II, 10%. At six months 94% of patients reported no change in bowel function. Conclusions The excellent long-term results and low morbidity presented, as well as the many advantages of prostate brachytherapy over other treatments, demonstrates that brachytherapy is an effective treatment for patients with transurethral resection and clinical organ-confined prostate cancer. PMID:27136466

  17. Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

    SciTech Connect

    Fox, C. D.; Kron, T.; Leahy, M.; Duchesne, G.; Williams, S.; Tai, K. H.; Haworth, A.; Herschtal, A.; Foroudi, F.

    2011-11-15

    Purpose: To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. Methods: An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. Results: The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. Conclusions: It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

  18. Single fraction multimodal image guided focal salvage high-dose-rate brachytherapy for recurrent prostate cancer

    PubMed Central

    Rischke, Hans-Christian; Meyer, Philipp Tobias; Knobe, Sven; Volgeova-Neher, Natalja; Kollefrath, Michael; Jilg, Cordula Annette; Grosu, Anca Ligia; Baltas, Dimos; Kroenig, Malte

    2016-01-01

    Purpose We present a novel method for treatment of locally recurrent prostate cancer (PCa) following radiation therapy: focal, multimodal image guided high-dose-rate (HDR) brachytherapy. Material and methods We treated two patients with recurrent PCa after primary (#1) or adjuvant (#2) external beam radiation therapy. Multiparametric magnetic resonance imaging (mpMRI), choline, positron emission tomography combined with computed tomography (PET/CT), or prostate-specific membrane antigen (PSMA)-PET combined with CT identified a single intraprostatic lesion. Positron emission tomography or magnetic resonance imaging – transrectal ultrasound (MRI-TRUS) fusion guided transperineal biopsy confirmed PCa within each target lesion. We defined a PET and mpMRI based gross tumor volume (GTV). A 5 mm isotropic margin was applied additionally to each lesion to generate a planning target volume (PTV), which accounts for technical fusion inaccuracies. A D90 of 18 Gy was intended in one fraction to each PTV using ultrasound guided HDR brachytherapy. Results Six month follow-up showed adequate prostate specific antygen (PSA) decline in both patients (ΔPSA 83% in patient 1 and ΔPSA 59.3% in patient 2). Follow-up 3-tesla MRI revealed regressive disease in both patients and PSMA-PET/CT showed no evidence of active disease in patient #1. No acute or late toxicities occurred. Conclusions Single fraction, focal, multimodal image guided salvage HDR brachytherapy for recurrent prostate cancer is a feasible therapy for selected patients with single lesions. This approach has to be evaluated in larger clinical trials. PMID:27504134

  19. Measurement uncertainty analysis of low-dose-rate prostate seed brachytherapy: post-implant dosimetry.

    PubMed

    Gregory, Kent J; Pattison, John E; Bibbo, Giovanni

    2015-03-01

    The minimal dose covering 90 % of the prostate volume--D 90--is arguably the most important dosimetric parameter in low-dose-rate prostate seed brachytherapy. In this study an analysis of the measurement uncertainties in D 90 from low-dose-rate prostate seed brachytherapy was conducted for two common treatment procedures with two different post-implant dosimetry methods. The analysis was undertaken in order to determine the magnitude of D 90 uncertainty, how the magnitude of the uncertainty varied when D 90 was calculated using different dosimetry methods, and which factors were the major contributors to the uncertainty. The analysis considered the prostate as being homogeneous and tissue equivalent and made use of published data, as well as original data collected specifically for this analysis, and was performed according to the Guide to the expression of uncertainty in measurement (GUM). It was found that when prostate imaging and seed implantation were conducted in two separate sessions using only CT images for post-implant analysis, the expanded uncertainty in D 90 values were about 25 % at the 95 % confidence interval. When prostate imaging and seed implantation were conducted during a single session using CT and ultrasound images for post-implant analysis, the expanded uncertainty in D 90 values were about 33 %. Methods for reducing these uncertainty levels are discussed. It was found that variations in contouring the target tissue made the largest contribution to D 90 uncertainty, while the uncertainty in seed source strength made only a small contribution. It is important that clinicians appreciate the overall magnitude of D 90 uncertainty and understand the factors that affect it so that clinical decisions are soundly based, and resources are appropriately allocated.

  20. Bioevaluation of 125I Ocu-Prosta seeds for application in prostate cancer brachytherapy

    PubMed Central

    Mukherjee, Archana; Sarma, Haladhar Dev; Saxena, Sanjay; Kumar, Yogendra; Chaudhari, Pradip; Goda, Jayant Sastri; Adurkar, Pranjal; Dash, Ashutosh; Samuel, Grace

    2014-01-01

    Background & objectives: In recent years, brachytherapy involving permanent radioactive seed implantation has emerged as an effective modality for the management of cancer of prostate. 125I-Ocu-Prosta seeds were indigenously developed and studies were carried out to assess the safety of the indigenously developed 125I-Ocu-Prosta seeds for treatment of prostate cancer. Methods: Animal experiments were performed to assess the likelihood of in vivo release of 125I from radioactive seeds and migration of seeds implanted in the prostate gland of the rabbit. In vivo release of 125I activity was monitored by serial blood sampling from the auricular vein and subsequent measurement of 125I activity. Serial computed tomography (CT) scans were done at regular intervals till 6 months post implant to assess the physical migration of the seeds. Results: The laser welded seeds maintained their hermeticity and prevented the in vivo release of 125I activity into the blood as no radioactivity was detected during follow up blood measurements. Our study showed that the miniature 125I seeds were clearly resolved in CT images. Seeds remained within the prostate gland during the entire study period. Moreover, the seed displacement was minimal even within the prostate gland. Interpretation & conclusions: Our findings have demonstrated that indigenously developed 125I-Ocu-Prosta seeds may be suitable for application in treatment of prostate cancer. PMID:24927341

  1. Long-Term Outcome for Clinically Localized Prostate Cancer Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2011-04-01

    Purpose: To present the largest series of prostate cancer brachytherapy patients treated with modern brachytherapy techniques and postimplant day 0 dosimetric evaluation. Methods and Materials: Between April 1995 and July 2006, 1,656 consecutive patients were treated with permanent interstitial brachytherapy. Risk group stratification was carried out according to the Mt. Sinai guidelines. Median follow-up was 7.0 years. The median day 0 minimum dose covering at least 90% of the target volume was 118.8% of the prescription dose. Cause of death was determined for each deceased patient. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on the evaluated survival parameters. Results: At 12 years, biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) for the entire cohort was 95.6%, 98.2%, and 72.6%, respectively. For low-, intermediate-, and high-risk patients, bPFS was 98.6%, 96.5%, and 90.5%; CSS was 99.8%, 99.3%, and 95.2%; and OS was 77.5%, 71.1%, and 69.2%, respectively. For biochemically controlled patients, the median posttreatment prostate-specific antigen (PSA) concentration was 0.02 ng/ml. bPFS was most closely related to percent positive biopsy specimens and risk group, while Gleason score was the strongest predictor of CSS. OS was best predicted by patient age, hypertension, diabetes, and tobacco use. At 12 years, biochemical failure and cause-specific mortality were 1.8% and 0.2%, 5.1% and 2.1%, and 10.4% and 7.1% for Gleason scores 5 to 6 and 7 and {>=}8, respectively. Conclusions: Excellent long-term outcomes are achievable with high-quality brachytherapy for low-, intermediate-, and high-risk patients. These results compare favorably to alternative treatment modalities including radical prostatectomy.

  2. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) practice guideline for the transperineal permanent brachytherapy of prostate cancer.

    PubMed

    Rosenthal, Seth A; Bittner, Nathan H J; Beyer, David C; Demanes, D Jeffrey; Goldsmith, Brian J; Horwitz, Eric M; Ibbott, Geoffrey S; Lee, W Robert; Nag, Subir; Suh, W Warren; Potters, Louis

    2011-02-01

    Transperineal permanent prostate brachytherapy is a safe and efficacious treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for permanent prostate brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachytherapy implant procedure, the importance of dosimetric parameters, and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful prostate brachytherapy program.

  3. The impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    NASA Astrophysics Data System (ADS)

    (Jay Chen, Zhe; Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-08-01

    Previous studies have shown that procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations strongly depends on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al (1998 Int. J. Radiat. Oncol. Biol. Phys. 41 1069-77) was used to characterize the edema evolutions previously observed during clinical PIB for prostate cancer. The concept of biologically effective dose, taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not appropriately taken into account, can increase the cell survival and decrease the probability of local control of PIB. The magnitude of an edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life of radioactive decay and decreasing photon energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days) is longer than

  4. Effect of Edema on Postimplant Dosimetry in Prostate Brachytherapy Using CT/MRI Fusion

    SciTech Connect

    Tanaka, Osamu Hayashi, Shinya; Matsuo, Masayuki; Nakano, Masahiro; Uno, Hiromi; Ohtakara, Kazuhiro; Miyoshi, Toshiharu; Deguchi, Takashi; Hoshi, Hiroaki

    2007-10-01

    Purpose: To investigate the time course of prostatic edema and the effect on the dose-volume histograms of the prostate for patients treated with brachytherapy. Methods and Materials: A total of 74 patients with prostate cancer were enrolled in this prospective study. A transrectal ultrasound-based preplan was performed 4 weeks before implantation and computed tomography/magnetic resonance imaging fusion-based postimplant dosimetry was performed on the day after implantation (Day 1) and 30 days after implantation (Day 30). The prostate volume, prostate volume covered by 100% of the prescription dose (V{sub 100}), and dose covering 90% of the prostate (D{sub 90}) were evaluated with prostatic edema over time. Results: Prostatic edema was greatest on Day 1, with the mean prostate volume 36% greater than the preplan transrectal ultrasound-based volume; it thereafter decreased over time. It was 9% greater than preplan volume on Day 30. The V{sub 100} increased 5.7% from Day 1 to Day 30, and the D{sub 90} increased 13.1% from Day 1 to Day 30. The edema ratio (postplan/preplan) on Day 1 of low-quality implants with a V{sub 100} of <80% was significantly greater than that of intermediate- to high-quality implants (>80% V{sub 100}; p = 0.0272). The lower V{sub 100} on Day 1 showed a greater increase from Day 1 to Day 30. A V{sub 100} on Day 1 of >92% is unlikely to increase >0% during the interval studied. Conclusion: Low-quality implants on Day 1 were highly associated with edema; however, such a low-quality implant on Day 1, with significant edema, tended to improve by Day 30. If a high-quality implant (V100 >92%) can be obtained on Day 1, a re-examination is no longer necessary.

  5. Tumour and immune cell dynamics explain the PSA bounce after prostate cancer brachytherapy

    PubMed Central

    Yamamoto, Yoichiro; Offord, Chetan P; Kimura, Go; Kuribayashi, Shigehiko; Takeda, Hayato; Tsuchiya, Shinichi; Shimojo, Hisashi; Kanno, Hiroyuki; Bozic, Ivana; Nowak, Martin A; Bajzer, Željko; Dingli, David

    2016-01-01

    Background: Interstitial brachytherapy for localised prostate cancer may be followed by transient increases in prostate-specific antigen (PSA) that resolve without therapy. Such PSA bounces may be associated with an improved outcome but often cause alarm in the patient and physician, and have defied explanation. Methods: We developed a mathematical model to capture the interactions between the tumour, radiation and anti-tumour immune response. The model was fitted to data from a large cohort of patients treated exclusively with interstitial brachytherapy. Immunohistological analysis for T-cell infiltration within the same tumours was also performed. Results: Our minimal model captures well the dynamics of the tumour after therapy, and suggests that a strong anti-tumour immune response coupled with the therapeutic effect of radiation on the tumour is responsible for the PSA bounce. Patients who experience a PSA bounce had a higher density of CD3 and CD8 cells within the tumour that likely contribute to the PSA bounce and the overall better outcomes observed. Conclusions: Our observations provide a novel and unifying explanation for the PSA bounce in patients with early prostate cancer and also have implications for the use of immune-based therapies in such patients to improve outcomes. PMID:27404586

  6. Predictive Factors and Management of Rectal Bleeding Side Effects Following Prostate Cancer Brachytherapy

    SciTech Connect

    Price, Jeremy G.; Stone, Nelson N.; Stock, Richard G.

    2013-08-01

    Purpose: To report on the incidence, nature, and management of rectal toxicities following individual or combination brachytherapy following treatment for prostate cancer over a 17-year period. We also report the patient and treatment factors predisposing to acute ≥grade 2 proctitis. Methods and Materials: A total of 2752 patients were treated for prostate cancer between October 1990 and April 2007 with either low-dose-rate brachytherapy alone or in combination with androgen depletion therapy (ADT) or external beam radiation therapy (EBRT) and were followed for a median of 5.86 years (minimum 1.0 years; maximum 19.19 years). We investigated the 10-year incidence, nature, and treatment of acute and chronic rectal toxicities following BT. Using univariate, and multivariate analyses, we determined the treatment and comorbidity factors predisposing to rectal toxicities. We also outline the most common and effective management for these toxicities. Results: Actuarial risk of ≥grade 2 rectal bleeding was 6.4%, though notably only 0.9% of all patients required medical intervention to manage this toxicity. The majority of rectal bleeding episodes (72%) occurred within the first 3 years following placement of BT seeds. Of the 27 patients requiring management for their rectal bleeding, 18 underwent formalin treatment and nine underwent cauterization. Post-hoc univariate statistical analysis revealed that coronary artery disease (CAD), biologically effective dose, rectal volume receiving 100% of the prescription dose (RV100), and treatment modality predict the likelihood of grade ≥2 rectal bleeding. Only CAD, treatment type, and RV100 fit a Cox regression multivariate model. Conclusions: Low-dose-rate prostate brachytherapy is very well tolerated and rectal bleeding toxicities are either self-resolving or effectively managed by medical intervention. Treatment planning incorporating adjuvant ADT while minimizing RV100 has yielded the best toxicity-free survival following

  7. Effect of post-implant edema on prostate brachytherapy treatment margins

    SciTech Connect

    Reed, Daniel R.; Wallner, Kent; Ford, Eric; Mueller, Amy; Merrick, Gregory; Maki, Jeffrey; Sutlief, Steven; Butler, Wayne

    2005-12-01

    Purpose: To determine if postimplant prostate brachytherapy treatment margins calculated on Day 0 differ substantially from those calculated on Day 30. Methods: Thirty patients with 1997 American Joint Commission on Cancer clinical stage T1-T2 prostatic carcinoma underwent prostate brachytherapy with I-125 prescribed to 144 Gy. Treatment planning methods included using loose seeds in a modified peripheral loading pattern and treatment margins (TMs) of 5-8 mm. Postimplant plain radiographs, computed tomography scans, and magnetic resonance scans were obtained 1-4 hours after implantation (Day 0). A second set of imaging studies was obtained at 30 days after implantation (Day 30) and similarly analyzed. Treatment margins were measured as the radial distance in millimeters from the prostate edge to the 100% isodose line. The TMs were measured and tabulated at 90{sup o} intervals around the prostate periphery at 0.6-cm intervals. Each direction was averaged to obtain the mean anterior, posterior, left, and right margins. Results: The mean overall TM increased from 2.6 mm ({+-}2.3) on Day 0 to 3.5 mm ({+-}2.4) on Day 30. The mean anterior margin increased from 1.2 mm on Day 0 to 1.8 mm on Day 30. The posterior margin increased from 1.2 mm on Day 0 to 2.8 mm on Day 30. The lateral treatment margins increased most over time, with mean right treatment margin increasing from 3.9 mm on Day 0 to 4.7 mm on Day 30. Conclusion: Treatment margins appear to be durable in the postimplant period, with a clinically insignificant increase from Day 0 to Day 30.

  8. Effects of seed migration on post-implant dosimetry of prostate brachytherapy

    SciTech Connect

    Gao, M.; Wang, J. Z.; Nag, S.; Gupta, N.

    2007-02-15

    Brachytherapy using permanent seed implants has been an effective treatment for prostate cancer. However, seeds will migrate after implant, thus making the evaluation of post-implant dosimetry difficult. In this study, we developed a computer program to simulate seed migration and analyzed dosimetric changes due to seed migration at various migration amounts. The study was based on 14 patients treated with Pd-103 at the James Cancer Hospital. Modeling of seed migration, including direction, distance as well as day of migration, was based on clinical observations. Changes of commonly used dosimetric parameters as a function of migration amount (2, 4, 6 mm respectively), prostate size (from 20 to 90 cc), and prostate region (central vs peripheral) were studied. Change of biological outcome (tumor control probability) due to migration was also estimated. Migration reduced prostate D90 to 99{+-}2% of original value in 2 mm migration, and the reduction increased to 94{+-}6% in 6 mm migration. The reduction of prostate dose led to a 14% (40%) drop in the tumor control probability for 2 mm (6 mm) migration, assuming radiosensitive tumors. However, migration has less effect on a prostate implanted with a larger number of seeds. Prostate V100 was less sensitive to migration than D90 since its mean value was still 99% of original value even in 6 mm migration. Migration also showed a different effect in the peripheral region vs the central region of the prostate, where the peripheral mean dose tended to drop more significantly. Therefore, extra activity implanted in the peripheral region during pre-plan can be considered. The detrimental effects of migration were more severe in terms of increasing the dose to normal structures, as rectum V50 may be 70% higher and urethra V100 may be 50% higher in the case of 6 mm migration. Quantitative knowledge of these effects is helpful in treatment planning and post-implant evaluation.

  9. Combination of 5α-reductase inhibitor with combined androgen blockade (CAB) as a novel cytoreductive regimen before prostate brachytherapy: Ultra-CAB

    PubMed Central

    Muro, Yusuke; Kosaka, Takeo; Mizuno, Ryuichi; Ohashi, Toshio; Shigematsu, Naoyuki; Oya, Mototsugu

    2015-01-01

    We report a first case of using a 5α-reductase inhibitor (5ARI) and combined androgen blockade (CAB) as a cytoreductive regimen before prostate brachytherapy. Prostate volume reduction with CAB is limited to approximately 40% in most cases, making it difficult to meet anatomical constraints to perform these procedures in cases with large prostate volume. With the added administration of 5ARI, further volume reduction can be expected. Here, we describe this cytoreductive regimen used in a 63 year-old prostate cancer patient who became eligible to receive brachytherapy after dutasteride (0.5 mg daily) was added to CAB and prostate volume reduction of 57% was achieved. PMID:26069888

  10. Combination of 5α-reductase inhibitor with combined androgen blockade (CAB) as a novel cytoreductive regimen before prostate brachytherapy: Ultra-CAB.

    PubMed

    Muro, Yusuke; Kosaka, Takeo; Mizuno, Ryuichi; Ohashi, Toshio; Shigematsu, Naoyuki; Oya, Mototsugu

    2015-01-01

    We report a first case of using a 5α-reductase inhibitor (5ARI) and combined androgen blockade (CAB) as a cytoreductive regimen before prostate brachytherapy. Prostate volume reduction with CAB is limited to approximately 40% in most cases, making it difficult to meet anatomical constraints to perform these procedures in cases with large prostate volume. With the added administration of 5ARI, further volume reduction can be expected. Here, we describe this cytoreductive regimen used in a 63 year-old prostate cancer patient who became eligible to receive brachytherapy after dutasteride (0.5 mg daily) was added to CAB and prostate volume reduction of 57% was achieved. PMID:26069888

  11. High-dose-rate brachytherapy delivered in two fractions as monotherapy for low-risk prostate cancer

    PubMed Central

    Alwers, Elizabeth; Cifuentes, Javier; Bobadilla, Ivan; Torres, Felipe; Arbelaez, Juan; Gaitan, Armando; Cortes, Helber; Acevedo, Yenny; Quintero, Paulo; Vasquez, Jaider

    2015-01-01

    Purpose High-dose-rate (HDR) brachytherapy has been accepted as an effective and safe method to treat prostate cancer. The aim of this study was to describe acute toxicity following HDR brachytherapy to the prostate, and to examine the association between dosimetric parameters and urinary toxicity in low-risk prostate cancer patients. Material and methods Patients with low-risk prostate cancer were given HDR brachytherapy as monotherapy in two 12.5 Gy fractions. Planning objectives for the planning target volume (PTV) were V100% ≥ 90% and V150% ≤ 35%. Planning objectives for organs at risk were V75% ≤ 1 cc for the bladder, rectum and perineum, and V125% ≤ 1 cc for the urethra. Toxicity was assessed three months after treatment using the Common Terminology Criteria for Adverse Events. Results Seventy-three patients were included in the analysis. Thirty-three patients (45%) reported having any type of toxicity in the three months following HDR brachytherapy. Most toxicity cases (26%) were grade 1 urinary toxicity. Mean coverage index was 0.89 and mean V100 was 88.85. Doses administered to the urethra were associated with urinary toxicity. Patients who received more than 111.3% of the prescribed dose in 1 cc of the urethra were four times more likely to have urinary toxicity compared to patients receiving less than 111.3% (OR = 4.71, 95% CI: 1.43-15.6; p = 0.011). Conclusions High-dose-rate brachytherapy administered as monotherapy for prostate cancer proved to be a safe alternative treatment for patients with low-risk prostate cancer. Urinary toxicity was associated with the dose administered to 1 cc and 0.1 cc of the urethra and was remarkably inferior to the reported toxicity in similar studies. PMID:25829931

  12. Iridium-192 brachytherapy in the treatment of cancer of the prostate

    SciTech Connect

    Donnelly, B.J.; Pedersen, J.E.; Porter, A.T.; McPhee, M.S. )

    1991-08-01

    Aggressive radiotherapy was used in 170 patients with advanced localized carcinoma of the prostate. After pelvic lymphadenectomy, 192Ir brachytherapy was used to deliver 3500 cGy to the prostate within 2 days. External-beam therapy (4500 cGy) was then given to a total of 8000 cGy. Random biopsies 18 months afterward were negative for residual cancer in 62 of 83 patients (75%), and 37 of 45 patients (82%) with pathologically proved localized disease remain without evidence of disease. Morbidity was significantly reduced in the most recent 70 patients by improvements in technique. The authors believe such therapy should be considered for patients with advanced stage B2 or C disease in particular.

  13. Optical fibre luminescence sensor for real-time LDR brachytherapy dosimetry

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; O'Keeffe, S.

    2016-05-01

    An optical fibre sensor for monitoring low dose radiation is presented. The sensor is based on a scintillation material embedded within the optical fibre core, which emits visible light when exposed to low level ionising radiation. The incident level of ionising radiation can be determined by analysing the optical emission. An optical fibre sensor is presented, based on radioluminescence whereby radiation sensitive scintillation material, terbium doped gadolinium oxysulphide (Gd2O2S:Tb), is embedded in a cavity of 250μm of a 500μm plastic optical fibre. The sensor is designed for in-vivo monitoring of the radiation dose during radio-active seed implantation for brachytherapy, in prostate cancer treatment, providing oncologists with real-time information of the radiation dose to the target area and/or nearby critical structures. The radiation from the brachytherapy seeds causes emission of visible light from the scintillation material through the process of radioluminescence, which penetrates the fibre, propagating along the optical fibre for remote detection using a multi-pixel photon counter. The sensor demonstrates a high sensitivity to Iodine-125, the radioactive source most commonly used in brachytherapy for treating prostate cancer.

  14. DuraSeal as a spacer to reduce rectal doses in low-dose rate brachytherapy for prostate cancer.

    PubMed

    Heikkilä, Vesa-Pekka; Kärnä, Aarno; Vaarala, Markku H

    2014-08-01

    The purpose of this study was to evaluate the utility of off-label use of DuraSeal polyethylene glycol (PEG) gel in low-dose rate (LDR) prostate brachytherapy seed implantation to reduce rectal doses. Diluted DuraSeal was easy to use and, in spite of a clearance effect, useful in decreasing D₂cc rectal doses. PMID:25201125

  15. Seed-based transrectal ultrasound-fluoroscopy registration method for intraoperative dosimetry analysis of prostate brachytherapy

    SciTech Connect

    Tutar, Ismail B.; Gong Lixin; Narayanan, Sreeram; Pathak, Sayan D.; Cho, Paul S.; Wallner, Kent; Kim, Yongmin

    2008-03-15

    Prostate brachytherapy is an effective treatment option for early-stage prostate cancer. During a prostate brachytherapy procedure, transrectal ultrasound (TRUS) and fluoroscopy imaging modalities complement each other by providing good visualization of soft tissue and implanted seeds, respectively. Therefore, the registration of these two imaging modalities, which are readily available in the operating room, could facilitate intraoperative dosimetry, thus enabling physicians to implant additional seeds into the underdosed portions of the prostate while the patient is still on the operating table. It is desirable to register TRUS and fluoroscopy images by using the seeds as fiducial markers. Although the locations of all the implanted seeds can be reconstructed from three fluoroscopy images, only a fraction of these seeds can be located in TRUS images. It is challenging to register the TRUS and fluoroscopy images by using the identified seeds, since the correspondence between them is unknown. Furthermore, misdetection of nonseed structures as seeds can lead to the inclusion of spurious points in the data set. We developed a new method called iterative optimal assignment (IOA) to overcome these challenges in TRUS-fluoroscopy registration. By using the Hungarian method in an optimization framework, IOA computes a set of transformation parameters that yield the one-to-one correspondence with minimum cost. We have evaluated our registration method at varying noise levels, seed detection rates, and number of spurious points using data collected from 25 patients. We have found that IOA can perform registration with an average root mean square error of about 0.2 cm even when the seed detection rate is only 10%. We believe that IOA can offer a robust solution to seed-based TRUS-fluoroscopy registration, thus making intraoperative dosimetry possible.

  16. High-Dose-Rate Brachytherapy Boost for Prostate Cancer: Comparison of Two Different Fractionation Schemes

    SciTech Connect

    Kaprealian, Tania; Weinberg, Vivian; Speight, Joycelyn L.; Gottschalk, Alexander R.; Roach, Mack; Shinohara, Katsuto; Hsu, I.-Chow

    2012-01-01

    Purpose: This is a retrospective study comparing our experience with high-dose-rate (HDR) brachytherapy boost for prostate cancer, using two different fractionation schemes, 600 cGy Multiplication-Sign 3 fractions (patient group 1) and 950 cGy Multiplication-Sign 2 fractions (patient group 2). Methods and Materials: A total of 165 patients were treated for prostate cancer using external beam radiation therapy up to a dose of 45 Gy, followed by an HDR brachytherapy prostate radiation boost. Between July 1997 and Nov 1999, 64 patients were treated with an HDR boost of 600 cGy Multiplication-Sign 3 fractions; and between June 2000 and Nov 2005, 101 patients were treated with an HDR boost of 950 cGy Multiplication-Sign 2 fractions. All but 9 patients had at least one of the following risk features: pretreatment prostate-specific antigen (PSA) level >10, a Gleason score {>=}7, and/or clinical stage T3 disease. Results: Median follow-up was 105 months for group 1 and 43 months for group 2. Patients in group 2 had a greater number of high-risk features than group 1 (p = 0.02). Adjusted for comparable follow-up, there was no difference in biochemical no-evidence-of-disease (bNED) rate between the two fractionation scheme approaches, with 5-year Kaplan-Meier estimates of 93.5% in group 1 and 87.3% in group 2 (p = 0.19). The 5-year estimates of progression-free survival were 86% for group 1 and 83% for group 2 (p = 0.53). Among high-risk patients, there were no differences in bNED or PFS rate due to fractionation. Conclusions: Results were excellent for both groups. Adjusted for comparable follow-up, no differences were found between groups.

  17. Iodine-125 radiolabeling of silver nanoparticles for in vivo SPECT imaging

    PubMed Central

    Chrastina, Adrian; Schnitzer, Jan E

    2010-01-01

    Silver nanoparticles are increasingly finding applications in medicine; however, little is known about their in vivo tissue distribution. Here, we have developed a rapid method for radiolabeling of silver nanoparticles with iodine-125 in order to track in vivo tissue uptake of silver nanoparticles after systemic administration by biodistribution analysis and single-photon emission computerized tomography (SPECT) imaging. Poly(N-vinyl-2 -pyrrolidone)-capped silver nanoparticles with an average size of 12 nm were labeled by chemisorption of iodine-125 with a > 80% yield of radiolabeling efficiency. Radiolabeled silver nanoparticles were intravenously injected in Balb/c mice, and the in vivo distribution pattern of these nanoparticles was evaluated by noninvasive whole-body SPECT imaging, which revealed uptake of the nanoparticles in the liver and spleen. Biodistribution analysis confirmed predominant accumulation of the silver nanoparticles in the spleen (41.5%ID/g) and liver (24.5%ID/g) at 24 h. Extensive uptake in the tissues of the reticuloendothelial system suggests that further investigation of silver nanoparticle interaction with hepatic and splenic tissues at the cellular level is critical for evaluation of the in vivo effects and potential toxicity of silver nanoparticles. This method enables rapid iodine-125 radiolabeling of silver nanoparticles with a specific activity sufficient for in vivo imaging and biodistribution analysis. PMID:20856841

  18. Dynamic dosimetry and edema detection in prostate brachytherapy: a complete system

    NASA Astrophysics Data System (ADS)

    Jain, A.; Deguet, A.; Iordachita, I.; Chintalapani, G.; Blevins, J.; Le, Y.; Armour, E.; Burdette, C.; Song, D.; Fichtinger, G.

    2008-03-01

    Purpose: Brachytherapy (radioactive seed insertion) has emerged as one of the most effective treatment options for patients with prostate cancer, with the added benefit of a convenient outpatient procedure. The main limitation in contemporary brachytherapy is faulty seed placement, predominantly due to the presence of intra-operative edema (tissue expansion). Though currently not available, the capability to intra-operatively monitor the seed distribution, can make a significant improvement in cancer control. We present such a system here. Methods: Intra-operative measurement of edema in prostate brachytherapy requires localization of inserted radioactive seeds relative to the prostate. Seeds were reconstructed using a typical non-isocentric C-arm, and exported to a commercial brachytherapy delivery system. Technical obstacles for 3D reconstruction on a non-isocentric C-arm include pose-dependent C-arm calibration; distortion correction; pose estimation of C-arm images; seed reconstruction; and C-arm to TRUS registration. Results: In precision-machined hard phantoms with 40-100 seeds and soft tissue phantoms with 45-87 seeds, we correctly reconstructed the seed implant shape with an average 3D precision of 0.35 mm and 0.24 mm, respectively. In a DoD Phase-1 clinical trial on 6 patients with 48-82 planned seeds, we achieved intra-operative monitoring of seed distribution and dosimetry, correcting for dose inhomogeneities by inserting an average of 4.17 (1-9) additional seeds. Additionally, in each patient, the system automatically detected intra-operative seed migration induced due to edema (mean 3.84 mm, STD 2.13 mm, Max 16.19 mm). Conclusions: The proposed system is the first of a kind that makes intra-operative detection of edema (and subsequent re-optimization) possible on any typical non-isocentric C-arm, at negligible additional cost to the existing clinical installation. It achieves a significantly more homogeneous seed distribution, and has the potential to

  19. Detailed urethral dosimetry in the evaluation of prostate brachytherapy-related urinary morbidity

    SciTech Connect

    Allen, Zachariah A.; Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian; Anderson, Richard L.; Murray, Brian C.; Galbreath, Robert W.

    2005-07-15

    Purpose: To evaluate the relationship between urinary morbidity after prostate brachytherapy and urethral doses calculated at the base, midprostate, apex, and urogenital diaphragm. Methods and Materials: From February 1998 through July 2002, 186 consecutive patients without a prior history of a transurethral resection underwent monotherapeutic brachytherapy (no supplemental external beam radiation therapy or androgen deprivation therapy) with urethral-sparing techniques (average urethral dose 100%-140% minimum peripheral dose) for clinical T1c-T2b (2002 AJCC) prostate cancer. The median follow-up was 45.5 months. Urinary morbidity was defined by time to International Prostate Symptom Score (IPSS) resolution, maximum increase in IPSS, catheter dependency, and the need for postimplant surgical intervention. An alpha blocker was initiated approximately 2 weeks before implantation and continued at least until the IPSS returned to baseline. Evaluated parameters included overall urethral dose (average and maximum), doses to the base, midprostate, apex, and urogenital diaphragm, patient age, clinical T stage, preimplant IPSS, ultrasound volume, isotope, and D90 and V100/150/200. Results: Of the 186 patients, 176 (94.6%) had the urinary catheter permanently removed on the day of implantation with only 1 patient requiring a urinary catheter >5 days. No patient had a urethral stricture and only 2 patients (1.1%) required a postbrachytherapy transurethral resection of the prostate (TURP). For the entire cohort, IPSS on average peaked 2 weeks after implantation with a mean and median time to IPSS resolution of 14 and 3 weeks, respectively. For the entire cohort, only isotope predicted for IPSS resolution, while neither overall average prostatic urethra nor segmental urethral dose predicted for IPSS resolution. The maximum postimplant IPSS increase was best predicted by preimplant IPSS and the maximum apical urethral dose. Conclusions: With the routine use of prophylactic alpha

  20. On the Sensitivity of α/β Prediction to Dose Calculation Methodology in Prostate Brachytherapy

    SciTech Connect

    Afsharpour, Hossein; Walsh, Sean; Collins Fekete, Charles-Antoine; Vigneault, Eric; Verhaegen, Frank; Beaulieu, Luc

    2014-02-01

    Purpose: To study the relationship between the accuracy of the dose calculation in brachytherapy and the estimations of the radiosensitivity parameter, α/β, for prostate cancer. Methods and Materials: In this study, Monte Carlo methods and more specifically the code ALGEBRA was used to produce accurate dose calculations in the case of prostate brachytherapy. Equivalent uniform biologically effective dose was calculated for these dose distributions and was used in an iso-effectiveness relationship with external beam radiation therapy. Results: By considering different levels of detail in the calculations, the estimation for the α/β parameter varied from 1.9 to 6.3 Gy, compared with a value of 3.0 Gy suggested by the American Association of Physicists in Medicine Task Group 137. Conclusions: Large variations of the α/β show the sensitivity of this parameter to dose calculation modality. The use of accurate dose calculation engines is critical for better evaluating the biological outcomes of treatments.

  1. Automatic segmentation of seeds and fluoroscope tracking (FTRAC) fiducial in prostate brachytherapy x-ray images

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Lee, Junghoon; Deguet, Anton; Song, Danny; Burdette, E. Clif; Prince, Jerry

    2010-02-01

    C-arm X-ray fluoroscopy-based radioactive seed localization for intraoperative dosimetry of prostate brachytherapy is an active area of research. The fluoroscopy tracking (FTRAC) fiducial is an image-based tracking device composed of radio-opaque BBs, lines, and ellipses that provides an effective means for pose estimation so that three-dimensional reconstruction of the implanted seeds from multiple X-ray images can be related to the ultrasound-computed prostate volume. Both the FTRAC features and the brachytherapy seeds must be segmented quickly and accurately during the surgery, but current segmentation algorithms are inhibitory in the operating room (OR). The first reason is that current algorithms require operators to manually select a region of interest (ROI), preventing automatic pipelining from image acquisition to seed reconstruction. Secondly, these algorithms fail often, requiring operators to manually correct the errors. We propose a fast and effective ROI-free automatic FTRAC and seed segmentation algorithm to minimize such human intervention. The proposed algorithm exploits recent image processing tools to make seed reconstruction as easy and convenient as possible. Preliminary results on 162 patient images show this algorithm to be fast, effective, and accurate for all features to be segmented. With near perfect success rates and subpixel differences to manual segmentation, our automatic FTRAC and seed segmentation algorithm shows promising results to save crucial time in the OR while reducing errors.

  2. Data fusion for planning target volume and isodose prediction in prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Nouranian, Saman; Ramezani, Mahdi; Mahdavi, S. Sara; Spadinger, Ingrid; Morris, William J.; Salcudean, Septimiu E.; Abolmaesumi, Purang

    2015-03-01

    In low-dose prostate brachytherapy treatment, a large number of radioactive seeds is implanted in and adjacent to the prostate gland. Planning of this treatment involves the determination of a Planning Target Volume (PTV), followed by defining the optimal number of seeds, needles and their coordinates for implantation. The two major planning tasks, i.e. PTV determination and seed definition, are associated with inter- and intra-expert variability. Moreover, since these two steps are performed in sequence, the variability is accumulated in the overall treatment plan. In this paper, we introduce a model based on a data fusion technique that enables joint determination of PTV and the minimum Prescribed Isodose (mPD) map. The model captures the correlation between different information modalities consisting of transrectal ultrasound (TRUS) volumes, PTV and isodose contours. We take advantage of joint Independent Component Analysis (jICA) as a linear decomposition technique to obtain a set of joint components that optimally describe such correlation. We perform a component stability analysis to generate a model with stable parameters that predicts the PTV and isodose contours solely based on a new patient TRUS volume. We propose a framework for both modeling and prediction processes and evaluate it on a dataset of 60 brachytherapy treatment records. We show PTV prediction error of 10:02+/-4:5% and the V100 isodose overlap of 97+/-3:55% with respect to the clinical gold standard.

  3. CT-guided brachytherapy of prostate cancer: reduction of effective dose from X-ray examination

    NASA Astrophysics Data System (ADS)

    Sanin, Dmitriy B.; Biryukov, Vitaliy A.; Rusetskiy, Sergey S.; Sviridov, Pavel V.; Volodina, Tatiana V.

    2014-03-01

    Computed tomography (CT) is one of the most effective and informative diagnostic method. Though the number of CT scans among all radiographic procedures in the USA and European countries is 11% and 4% respectively, CT makes the highest contribution to the collective effective dose from all radiographic procedures, it is 67% in the USA and 40% in European countries [1-5]. Therefore it is necessary to understand the significance of dose value from CT imaging to a patient . Though CT dose from multiple scans and potential risk is of great concern in pediatric patients, this applies to adults as well. In this connection it is very important to develop optimal approaches to dose reduction and optimization of CT examination. International Commission on Radiological Protection (ICRP) in its publications recommends radiologists to be aware that often CT image quality is higher than it is necessary for diagnostic confidence[6], and there is a potential to reduce the dose which patient gets from CT examination [7]. In recent years many procedures, such as minimally invasive surgery, biopsy, brachytherapy and different types of ablation are carried out under guidance of computed tomography [6;7], and during a procedures multiple CT scans focusing on a specific anatomic region are performed. At the Clinics of MRRC different types of treatment for patients with prostate cancer are used, incuding conformal CT-guided brachytherapy, implantation of microsources of I into the gland under guidance of spiral CT [8]. So, the purpose of the study is to choose optimal method to reduce radiation dose from CT during CT-guided prostate brachytherapy and to obtain the image of desired quality.

  4. Comparison of High-Dose Proton Radiotherapy and Brachytherapy in Localized Prostate Cancer: A Case-Matched Analysis

    SciTech Connect

    Coen, John J.; Zietman, Anthony L.; Rossi, Carl J.; Grocela, Joseph A.; Efstathiou, Jason A.; Yan, Yan; Shipley, William U.

    2012-01-01

    Purpose: To report a case-matched analysis comparing high-dose external-beam radiation (EBRT) for prostate cancer delivered on Proton Radiation Oncology Group (PROG) 95-09, a randomized trial, with permanent prostate brachytherapy over the same era. Methods: From 1996 to 1999, 196 patients were accrued to the high-dose arm (79.2 Gray equivalent (GyE) using photons and protons) of PROG 95-09 at the Massachusetts General Hospital and Loma Linda University Medical Center. Entry criteria specified T1-2 and prostate-specific antigen {<=}15 ng/mL. When Gleason score >7 was excluded, 177 men were left for case matching. At Massachusetts General Hospital, 203 similar patients were treated by a single brachytherapist from 1997 to 2002. Minimum follow-up was 3 years. Case matching, based on T stage, Gleason score, prostate-specific antigen, and age resulted in 141 matches (282 patients). Median follow-up was 8.6 and 7.4 years for EBRT and brachytherapy, respectively. The primary endpoint was biochemical failure (BF). Results: Using the Phoenix definition, the 8-year BF rates were 7.7% and 16.1% for EBRT and brachytherapy, respectively (p = 0.42). A stratified analysis was performed by risk group. In the EBRT group, 113 and 28 patients were low and intermediate risk, respectively. In the brachytherapy group, 118 and 23 were. When stratified by risk group, the BF rates were similar by either technique. Conclusions: High-dose EBRT and brachytherapy result in similar BF rates for men with localized prostate cancer. Comparative quality-of-life and cost-effectiveness studies are warranted.

  5. The Influence of Prostate Volume on Outcome After High-Dose-Rate Brachytherapy Alone for Localized Prostate Cancer

    SciTech Connect

    Le, Hien Rojas, Ana; Alonzi, Roberto; Hughes, Robert; Ostler, Peter; Lowe, Gerry; Bryant, Linda; Hoskin, Peter

    2013-10-01

    Objective: To determine whether late genitourinary toxicity, biochemical control of prostate cancer, and dosimetric parameters in patients with large prostate glands is different from those variables in men with smaller glands after treatment with high-dose-rate brachytherapy alone (HDR-BT). Methods: From November 2003 to July 2009, 164 patients with locally advanced prostate carcinoma were sequentially enrolled and treated with 34 or 36 Gy in 4 fractions and 31.5 Gy in 3 fractions of {sup 192}Ir HDR-BT alone. The median follow-up time was 71 months. Gland size was not considered in the selection criteria for this study. Estimates of freedom from biochemical relapse (FFbR) and late morbidity, stratified by median clinical target volume (CTV), were obtained, and differences were compared. Results: The median CTV volume was 60 cc (range, 15-208 cc). Dose–volume parameters D90 and V100 (ie, minimum dose to 90% of the prostate volume and volume receiving 100% of the prescribed isodose) achieved in patients with glands ≥60 cc were not significantly different from those with glands <60 cc (P≥.2). Nonetheless, biochemical control in patients with larger CTV was significantly higher (91% vs 78% at 6 years; P=.004). In univariate and multivariate analysis, CTV was a significant predictor for risk of biochemical relapse. This was not at the expense of an increase in either moderate (P=.6) or severe (P=.3) late genitourinary toxicity. The use of hormonal therapy was 17% lower in the large gland group (P=.01). Conclusions: Prostate gland size does not affect dosimetric parameters in HDR-BT assessed by D90 and V100. In patients with larger glands, a significantly higher biochemical control of disease was observed, with no difference in late toxicity. This improvement cannot be attributed to differences in dosimetry. Gland size should not be considered in the selection of patients for HDR-BT.

  6. [Intraoperative and post-implant dosimetry in patients treated with permanent prostate implant brachytherapy].

    PubMed

    Herein, András; Ágoston, Péter; Szabó, Zoltán; Jorgo, Kliton; Markgruber, Balázs; Pesznyák, Csilla; Polgár, Csaba; Major, Tibor

    2015-06-01

    The purpose of our work was to compare intraoperative and four-week post-implant dosimetry for loose and stranded seed implants for permanent prostate implant brachytherapy. In our institute low-dose-rate (LDR) prostate brachytherapy is performed with encapsulated I-125 isotopes (seeds) using transrectal ultrasound guidance and metal needles. The SPOT PRO 3.1 (Elekta, Sweden) system is used for treatment planning. In this study the first 79 patients were treated with loose seed (LS) technique, the consecutive patients were treated with stranded seed (SS) technique. During intraoperative planning the dose constraints were the same for both techniques. All LSs were placed inside the prostate capsule, while with SS a 2 mm margin around the prostate was allowed for seed positioning. The prescribed dose for the prostate was 145 Gy. This study investigated prostate dose coverage in 30-30 randomly selected patients with LS and SS. Four weeks after the implantation native CT and MRI were done and CT/MRI image fusion was performed. The target was contoured on MRI and the plan was prepared on CT data. To assess the treatment plan dose-volume histograms were used. For the target coverage V100, V90, D90, D100, for the dose inhomogeneity V150, V200, and the dose-homogeneity index (DHI), for dose conformality the conformal index (COIN) were calculated. Intraoperative and postimplant plans were compared. The mean V100 values decreased at four-week plan for SS (97% vs. 84%) and for LS (96% vs. 80%) technique, as well. Decrease was observed for all parameters except for the DHI value. The DHI increased for SS (0.38 vs. 0.41) and for LS (0.38 vs. 0.47) technique, as well. The COIN decreased for both techniques at four-week plan (SS: 0.63 vs. 0.57; LS: 0.67 vs. 0.50). All differences were significant except for the DHI value at SS technique. The percentage changes were not significant, except the COIN value. The dose coverage of the target decreased significantly at four-week plans

  7. Robustness of IPSA optimized high-dose-rate prostate brachytherapy treatment plans to catheter displacements

    PubMed Central

    Whitaker, May

    2016-01-01

    Purpose Inverse planning simulated annealing (IPSA) optimized brachytherapy treatment plans are characterized with large isolated dwell times at the first or last dwell position of each catheter. The potential of catheter shifts relative to the target and organs at risk in these plans may lead to a more significant change in delivered dose to the volumes of interest relative to plans with more uniform dwell times. Material and methods This study aims to determine if the Nucletron Oncentra dwell time deviation constraint (DTDC) parameter can be optimized to improve the robustness of high-dose-rate (HDR) prostate brachytherapy plans to catheter displacements. A set of 10 clinically acceptable prostate plans were re-optimized with a DTDC parameter of 0 and 0.4. For each plan, catheter displacements of 3, 7, and 14 mm were retrospectively applied and the change in dose volume histogram (DVH) indices and conformity indices analyzed. Results The robustness of clinically acceptable prostate plans to catheter displacements in the caudal direction was found to be dependent on the DTDC parameter. A DTDC value of 0 improves the robustness of planning target volume (PTV) coverage to catheter displacements, whereas a DTDC value of 0.4 improves the robustness of the plans to changes in hotspots. Conclusions The results indicate that if used in conjunction with a pre-treatment catheter displacement correction protocol and a tolerance of 3 mm, a DTDC value of 0.4 may produce clinically superior plans. However, the effect of the DTDC parameter in plan robustness was not observed to be as strong as initially suspected. PMID:27504129

  8. Rectal-wall dose dependence on postplan timing after permanent-seed prostate brachytherapy

    SciTech Connect

    Taussky, Daniel; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: Juanita.crook@rmp.uhn.on.ca

    2006-06-01

    Purpose: Dose to rectal wall after permanent-seed prostate brachytherapy is dependent on distance between posterior prostatic seeds and anterior rectal wall and is influenced by postimplant periprostatic edema. We analyzed the effect of postplan timing on anterior rectal-wall dose. Methods and Materials: Twenty patients received permanent seed {sup 125}I brachytherapy as monotherapy (145 Gy). Implants were preplanned by use of transrectal ultrasound (TRUS) and carried out by use of preloaded needles. Postimplant dosimetry was calculated by use of magnetic resonance imaging-computed tomography fusion on Days 1, 8, and 30. The anterior rectal-wall dose is reported as the isodose enclosing 1.0 or 2.0 cc of rectal wall and as the RV100 in cc. Results: The dose to rectal wall increased progressively over time. The median increase in dose to 1.0 cc of rectal wall (RD [1 cc]) from Day 1 to 30 was 39.2 Gy (p < 0.001). RV100 increased from a median of 0.07 cc on Day 1 to 0.67 cc on Day 30. The most significant predictor of rectal-wall dose (RD [1 cc], RD [2 cc], or RV100) was the time of evaluation (p < 0.001). Conclusion: Although periprostatic edema cannot be quantified by postimplant imaging, the dose to the anterior rectal wall increases significantly over time as prostatic and periprostatic edema resolve. Critical-organ dose reporting and guidelines for minimizing toxicity must take into account the time of the assessment.

  9. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis.

    PubMed

    Aoun, Fouad; Limani, Ksenija; Peltier, Alexandre; Marcelis, Quentin; Zanaty, Marc; Chamoun, Alexandre; Vanden Bossche, Marc; Roumeguère, Thierry; van Velthoven, Roland

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ (2) test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p < 0.05). Median oncologic follow-up was 83 months (13-123 months) in the HIFU cohort and 44 months (13-89 months) in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p < 0.05). No statistically significant difference in metastasis-free, cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results. PMID:26357511

  10. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis

    PubMed Central

    Aoun, Fouad; Limani, Ksenija; Peltier, Alexandre; Marcelis, Quentin; Zanaty, Marc; Chamoun, Alexandre; Vanden Bossche, Marc; Roumeguère, Thierry; van Velthoven, Roland

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ2 test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p < 0.05). Median oncologic follow-up was 83 months (13–123 months) in the HIFU cohort and 44 months (13–89 months) in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p < 0.05). No statistically significant difference in metastasis-free, cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results. PMID:26357511

  11. Distant Metastases Following Permanent Interstitial Brachytherapy for Patients With Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2012-02-01

    Purpose: Recent publications have suggested high-risk patients undergoing radical prostatectomy have a lower risk of distant metastases and improved cause-specific survival (CSS) than patients receiving definitive external beam radiation therapy (XRT). To date, none of these studies has compared distant metastases and CSS in brachytherapy patients. In this study, we evaluate such parameters in a consecutive cohort of brachytherapy patients. Methods and Materials: From April 1995 to June 2007, 1,840 consecutive patients with clinically localized prostate cancer were treated with brachytherapy. Risk groups were stratified according to National Comprehensive Cancer Network ( (www.nccn.org)) guidelines. Subgroups of 658, 893, and 289 patients were assigned to low, intermediate, and high-risk categories. Median follow-up was 7.2 years. Along with brachytherapy implantation, 901 (49.0%) patients received supplemental XRT, and 670 (36.4%) patients received androgen deprivation therapy (median duration, 4 months). The mode of failure (biochemical, local, or distant) was determined for each patient for whom therapy failed. Cause of death was determined for each deceased patient. Multiple parameters were evaluated for impact on outcome. Results: For the entire cohort, metastases-free survival (MFS) and CSS at 12 years were 98.1% and 98.2%, respectively. When rates were stratified by low, intermediate, and high-risk groups, the 12-year MFS was 99.8%, 98.1%, and 93.8% (p < 0.001), respectively. CSS rates were 99.8%, 98.0%, and 95.3% (p < 0.001) for low, intermediate, and high-risk groups, respectively. Biochemical progression-free survival was 98.7%, 95.9% and 90.4% for low, intermediate, and high-risk patients, respectively (p < 0.001). In multivariate Cox-regression analysis, MFS was mostly closely related to Gleason score and year of treatment, whereas CSS was most closely associated with Gleason score. Conclusions: Excellent CSS and MFS rates are achievable with high

  12. Intraoperative Ultrasound-Fluoroscopy Fusion can Enhance Prostate Brachytherapy Quality

    SciTech Connect

    Orio, Peter F.; Tutar, Ismail B.; Narayanan, Sreeram; Arthurs, Sandra; Cho, Paul S.; Kim, Yongmin; Merrick, Gregory; Wallner, Kent E.

    2007-09-01

    Purpose: To evaluate a transrectal ultrasound (TRUS)-fluoroscopy fusion-based intraoperative dosimetry system. Method and Materials: Twenty-five patients were treated for prostate cancer with Pd-103 implantation. After the execution of the treatment plan, two sets of TRUS images were collected using the longitudinal and axial transducers of a biplanar probe. Then, three fluoroscopic images were acquired at 0, -15 and +15{sup o}. The three-dimensional locations of all implanted seeds were reconstructed from fluoroscopic images. A subset of the implanted seeds was manually identified in TRUS images and used as fiducial markers to perform TRUS-fluoroscopy fusion. To improve the implant quality, additional seeds were placed if adverse isodose patterns were identified during visual inspection. If additional seeds were placed, intraoperative dosimetry was repeated. Day 0 computed tomography-based dosimetry was compared with final intraoperative dosimetry to validate dosimetry achieved in the implant suite. Results: An average of additional 4.0 seeds was implanted in 16 patients after initial intraoperative dose evaluation. Based on TRUS-fluoroscopy fusion-based dosimetry, the V100 improved from 86% to 93% (p = 0.005), whereas D90 increased from 94% to 109% (p = 0.011) with the guided additional seed implantation. No statistical difference was observed in V200 and V300 values. V100 and D90 values were 95 {+-} 4% and 120 {+-} 24%, respectively, based on the final intraoperative dosimetry evaluation, compared with 95 {+-} 4% and 122 {+-} 24%, respectively, based on Day 0 computed tomography-based dosimetry. Conclusions: Implantation of extra seeds based on TRUS-fluoroscopy fusion-based intraoperative dosimetry can improve the final V100 and D90 values with minimal increase in V200 and V300 values.

  13. Salvage HDR Brachytherapy for Recurrent Prostate Cancer After Previous Definitive Radiation Therapy: 5-Year Outcomes

    SciTech Connect

    Chen, Chien Peter; Weinberg, Vivian; Shinohara, Katsuto; Roach, Mack; Nash, Marc; Gottschalk, Alexander; Chang, Albert J.; Hsu, I-Chow

    2013-06-01

    Purpose: Evaluate efficacy and toxicity of salvage high-dose-rate brachytherapy (HDRB) for locally recurrent prostate cancer after definitive radiation therapy (RT). Methods and Materials: We retrospectively analyzed 52 consecutively accrued patients undergoing salvage HDRB between 1998 and 2009 for locally recurrent prostate cancer after previous definitive RT. After pathologic confirmation of locally recurrent disease, patients received 36 Gy in 6 fractions. Twenty-four patients received neoadjuvant hormonal therapy before salvage, and no patients received adjuvant hormonal therapy. Determination of biochemical failure after salvage HDRB was based on the Phoenix definition. Overall survival (OS) and bF distributions were calculated using the Kaplan-Meier method. Univariate analyses were performed to identify predictors of biochemical control. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities, based on Common Terminology Criteria for Adverse Events (version 4), were documented. Results: Median follow-up after salvage HDRB was 59.6 months. The 5-year OS estimate was 92% (95% confidence interval [CI]: 80%-97%) with median survival not yet reached. Five-year biochemical control after salvage was 51% (95% CI: 34%-66%). Median PSA nadir postsalvage was 0.1 (range: 0-7.2) reached at a median of 10.2 months after completing HDRB. As for complications, acute and late grade 3 GU toxicities were observed in only 2% and 2%, respectively. No grade 2 or higher acute GI events and 4% grade 2 GI late events were observed. On univariate analysis, disease-free interval after initial definitive RT (P=.07), percent of positive cores at the time of diagnosis (P=.08), interval from first recurrence to salvage HDRB (P=.09), and pre-HDRB prostate-specific antigen (P=.07) were each of borderline significance in predicting biochemical control after salvage HDRB. Conclusions: Prostate HDRB is an effective salvage modality with relatively few long-term toxicities. We

  14. Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

    SciTech Connect

    Genebes, Caroline; Filleron, Thomas; Graff, Pierre; Jonca, Frédéric; Huyghe, Eric; Thoulouzan, Matthieu; Soulie, Michel; Malavaud, Bernard; Aziza, Richard; Brun, Thomas; Delannes, Martine; Bachaud, Jean-Marc

    2013-11-15

    Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes.

  15. Low-dose rate prostate brachytherapy is well tolerated in patients with a history of inflammatory bowel disease

    SciTech Connect

    Peters, Christopher A. . E-mail: christopher.peters@mountsinai.org; Cesaretti, Jamie A.; Stone, Nelson N.; Stock, Richard G.

    2006-10-01

    Purpose: We report on the follow-up of 24 patients with a prior history of inflammatory bowel disease (IBD) treated with brachytherapy for early-stage prostate cancer. Methods and Materials: Twenty-four patients with a history of inflammatory bowel disease (17 with ulcerative colitis (UC), 7 with Crohn's disease [CD]) underwent prostate brachytherapy between 1992 and 2004. Fifteen patients were treated with I-125 implantation and 6 patients were treated with Pd-103 alone or in combination with 45 Gy external beam radiation. Charts were reviewed for all patients, and all living patients were contacted by phone. National Cancer Institute common toxicity scores for proctitis were assigned to all patients. Actuarial risk of late toxicity was calculated by the Kaplan-Meier method. Statistical analysis was performed using SPSS software. Follow-up ranged from 3 to 126 months (median, 48.5 months; mean, 56.8 months). Results: None of the patients experienced Grade 3 or 4 rectal toxicity. Four patients experienced Grade 2 late rectal toxicity. The 5-year actuarial freedom from developing late Grade 2 rectal toxicity was 81%. At a median follow-up of 48.5 months, 23 patients were alive and had no evidence of disease with a median prostate-specific antigen for the sample of 0.1 ng/mL (range, <0.05-0.88 ng/mL). One patient died of other causes unrelated to his prostate cancer. Conclusions: Prostate brachytherapy is well tolerated in patients with a history of controlled IBD. Therefore, brachytherapy should be considered a viable therapeutic option in this patient population.

  16. Androgen-deprivation therapy does not impact cause-specific or overall survival after permanent prostate brachytherapy

    SciTech Connect

    Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Allen, Zachariah A. M.S.; Adamovich, Edward

    2006-07-01

    Purpose: To determine if androgen-deprivation therapy (ADT) has an impact on cause-specific, biochemical progression-free, or overall survival after prostate brachytherapy. Methods and Materials: From April 1995 through June 2002, 938 consecutive patients underwent brachytherapy for clinical Stage T1b to T3a (2002 AJCC) prostate cancer. All patients underwent brachytherapy more than 3 years before analysis. A total of 382 patients (40.7%) received ADT with a duration of 6 months or less in 277 and more than 6 months in 105. The median follow-up was 5.4 years. Multiple clinical, treatment, and dosimetric parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific, biochemical progression-free, and overall survival rates for the entire cohort were 96.4%, 95.9%, and 78.1%, respectively. Except for biochemical progression-free survival in high-risk patients, ADT did not statistically impact any of the three survival categories. A Cox linear-regression analysis demonstrated that Gleason score was the best predictor of cause-specific survival, whereas percent-positive biopsies, prostate volume, and risk group predicted for biochemical progression-free survival. Patient age and tobacco use were the strongest predictors of overall survival. One hundred two patients have died, with 80 of the deaths a result of cardiovascular disease (54) and second malignancies (26). To date, only 12 patients have died of metastatic prostate cancer. Conclusions: After brachytherapy, androgen-deprivation therapy did not have an impact on cause-specific or overall survival for any risk group; however, ADT had a beneficial effect on biochemical progression-free survival in high-risk patients. Cardiovascular disease and second malignancies far outweighed prostate cancer as competing causes of death.

  17. Young Men Have Equivalent Biochemical Outcomes Compared With Older Men After Treatment With Brachytherapy for Prostate Cancer

    SciTech Connect

    Burri, Ryan J.; Ho, Alice Y.; Forsythe, Kevin; Cesaretti, Jamie A.; Stone, Nelson N.; Stock, Richard G.

    2010-08-01

    Purpose: To evaluate retrospectively the biochemical outcomes of young men treated with low-dose-rate brachytherapy for prostate cancer. Methods and Materials: From 1990 to 2005, 1,665 men with clinically localized prostate cancer were treated with low-dose-rate brachytherapy {+-} hormone therapy (HT) {+-} external beam radiotherapy and underwent {>=}2 years of follow-up. Patients were stratified on the basis of age: {<=}60 (n = 378) and >60 years (n = 1,287). Biochemical failure was defined as a prostate-specific antigen (PSA) nadir plus 2 ng/mL. Univariate and multivariate analyses were used to determine the association of variables with freedom from biochemical failure (FFbF). Results: Median follow-up was 68 months (range, 24-180) for men {<=}60 years and 66 months (range, 24-200) for men >60. For the entire group, the actuarial 5- and 8-year FFbF rates were 94% and 88%, respectively. Men {<=}60 demonstrated similar 5- and 8-year FFbF (95% and 92%) compared with men >60 (93% and 87%; p = 0.071). A larger percent of young patients presented with low-risk disease; lower clinical stage, Gleason score (GS), and pretreatment PSA values; were treated after 1997; did not receive any HT; and had a high biologic effective dose (BED) of radiation (all ps <0.001). On multivariate analysis, PSA (p = 0.001), GS (p = 0.005), and BED (p < 0.001) were significantly associated with FFbF, but age was not (p = 0.665). Conclusion: Young men achieve excellent 5- and 8-year biochemical control rates that are comparable to those of older men after prostate brachytherapy. Young age should not be a deterrent when considering brachytherapy as a primary treatment option for clinically localized prostate cancer.

  18. BrachyView, a novel in-body imaging system for HDR prostate brachytherapy: Experimental evaluation

    SciTech Connect

    Safavi-Naeini, M.; Han, Z.; Alnaghy, S.; Cutajar, D.; Petasecca, M.; Lerch, M. L. F.; Rosenfeld, A. B.; Franklin, D. R.; Bucci, J.; Carrara, M.; Zaider, M.

    2015-12-15

    Purpose: This paper presents initial experimental results from a prototype of high dose rate (HDR) BrachyView, a novel in-body source tracking system for HDR brachytherapy based on a multipinhole tungsten collimator and a high resolution pixellated silicon detector array. The probe and its associated position estimation algorithms are validated and a comprehensive evaluation of the accuracy of its position estimation capabilities is presented. Methods: The HDR brachytherapy source is moved through a sequence of positions in a prostate phantom, for various displacements in x, y, and z. For each position, multiple image acquisitions are performed, and source positions are reconstructed. Error estimates in each dimension are calculated at each source position and combined to calculate overall positioning errors. Gafchromic film is used to validate the accuracy of source placement within the phantom. Results: More than 90% of evaluated source positions were estimated with an error of less than one millimeter, with the worst-case error being 1.3 mm. Experimental results were in close agreement with previously published Monte Carlo simulation results. Conclusions: The prototype of HDR BrachyView demonstrates a satisfactory level of accuracy in its source position estimation, and additional improvements are achievable with further refinement of HDR BrachyView’s image processing algorithms.

  19. A simple analytical method for heterogeneity corrections in low dose rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Hueso-González, Fernando; Vijande, Javier; Ballester, Facundo; Perez-Calatayud, Jose; Siebert, Frank-André

    2015-07-01

    In low energy brachytherapy, the presence of tissue heterogeneities contributes significantly to the discrepancies observed between treatment plan and delivered dose. In this work, we present a simplified analytical dose calculation algorithm for heterogeneous tissue. We compare it with Monte Carlo computations and assess its suitability for integration in clinical treatment planning systems. The algorithm, named as RayStretch, is based on the classic equivalent path length method and TG-43 reference data. Analytical and Monte Carlo dose calculations using Penelope2008 are compared for a benchmark case: a prostate patient with calcifications. The results show a remarkable agreement between simulation and algorithm, the latter having, in addition, a high calculation speed. The proposed analytical model is compatible with clinical real-time treatment planning systems based on TG-43 consensus datasets for improving dose calculation and treatment quality in heterogeneous tissue. Moreover, the algorithm is applicable for any type of heterogeneities.

  20. SU-FF-T-390: In-Vivo Prostate Brachytherapy Absorbed Dose Measurements

    SciTech Connect

    Gueye, Paul; Velasco, Carlos; Keppel, Cynthia; Murphy, B; Sinesi, C

    2009-06-01

    Purpose: In-vivo prostate brachytherapy absorbed dosimetrydetector using scintillating fibers. Method and Materials: Five pairs of 85.5 {+-} 0.05 cm long blue shifted scintillating fibers (model BCF-10) with 1 mm{sup 2} cross sectional area were placed in a mixture of gelatin (368.6 {+-} 0.5 grams) and water (3.78 {+-} 0.025 liters) to measured the absorbed dose delivered by a 12 Ci {sup 192}Ir HDR source. The fibers were held by a 7 x 7 cm{sup 2} template grid and optically connected to a 16-channel multianode photomultiplier tube (Hamamatsu, model H6568). Each pair consisted of one fiber 4 mm shorter than the other one to extract the dose by the subtraction method. A dose atlas was used for radiation delivered to the phantom. The plans followed delivered 5 and 7 Gy to a point located 2.0 centimeters away from the central dwelling positions. A total of 32 data points were acquired in a plan to assess the linearity and reproducibility of the measurements.Results: Reproducibility of the data was found to be within 5% and the overall accuracy of the system estimated to be {+-}5.5%. The linearity of the data for all 7 measureddose values (ranging from 0.6 to 7 Gy), gives a slope of 312 counts/Gy with a 1.4% relative deviation. Conclusion: This work indicates the possibility of measuring in real-time the dose effectively delivered to a biological system during prostate brachytherapy treatments. The availability of commercially thin (150 {micro}m) scintillating fibers opens the capability of using such system during clinical treatments (by embedding the fibers within the catheters) with the advantage of performing real-time adjustment of the dose delivery.

  1. An image-guidance system for dynamic dose calculation in prostate brachytherapy using ultrasound and fluoroscopy

    SciTech Connect

    Kuo, Nathanael Prince, Jerry L.; Dehghan, Ehsan; Deguet, Anton; Mian, Omar Y.; Le, Yi; Song, Danny Y.; Burdette, E. Clif; Fichtinger, Gabor; Lee, Junghoon

    2014-09-15

    Purpose: Brachytherapy is a standard option of care for prostate cancer patients but may be improved by dynamic dose calculation based on localized seed positions. The American Brachytherapy Society states that the major current limitation of intraoperative treatment planning is the inability to localize the seeds in relation to the prostate. An image-guidance system was therefore developed to localize seeds for dynamic dose calculation. Methods: The proposed system is based on transrectal ultrasound (TRUS) and mobile C-arm fluoroscopy, while using a simple fiducial with seed-like markers to compute pose from the nonencoded C-arm. Three or more fluoroscopic images and an ultrasound volume are acquired and processed by a pipeline of algorithms: (1) seed segmentation, (2) fiducial detection with pose estimation, (3) seed matching with reconstruction, and (4) fluoroscopy-to-TRUS registration. Results: The system was evaluated on ten phantom cases, resulting in an overall mean error of 1.3 mm. The system was also tested on 37 patients and each algorithm was evaluated. Seed segmentation resulted in a 1% false negative rate and 2% false positive rate. Fiducial detection with pose estimation resulted in a 98% detection rate. Seed matching with reconstruction had a mean error of 0.4 mm. Fluoroscopy-to-TRUS registration had a mean error of 1.3 mm. Moreover, a comparison of dose calculations between the authors’ intraoperative method and an independent postoperative method shows a small difference of 7% and 2% forD{sub 90} and V{sub 100}, respectively. Finally, the system demonstrated the ability to detect cold spots and required a total processing time of approximately 1 min. Conclusions: The proposed image-guidance system is the first practical approach to dynamic dose calculation, outperforming earlier solutions in terms of robustness, ease of use, and functional completeness.

  2. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy.

    PubMed

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-01

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm(3) calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  3. Implementation of High-Dose-Rate Brachytherapy and Androgen Deprivation in Patients With Prostate Cancer

    SciTech Connect

    Lilleby, Wolfgang; Tafjord, Gunnar; Raabe, Nils K.

    2012-07-01

    Purpose: To evaluate outcome (overall survival [OS], the actuarial 5-year cancer-specific survival [CSS], disease-free survival [DFS], biochemical failure-free survival [BFS]), complications and morbidity in patients treated with high-dose-rate brachytherapy (HDR-BT) boost and hormonal treatment with curative aims. Methods: Between 2004 and 2009, 275 prospectively followed pN0/N0M0 patients were included: 19 patients (7%) with T2, Gleason score 7 and prostate-specific antigen (PSA) <10 and 256 patients (93%) with T3 or Gleason score 8-10 or PSA >20 received multimodal treatment with conformal four-field radiotherapy (prostate/vesiculae 2 Gy Multiplication-Sign 25) combined with HDR-BT (iridium 192; prostate 10 Gy Multiplication-Sign 2) with long-term androgen deprivation therapy (ADT). Results: After a median observation time of 44.2 months (range, 10.4-90.5 months) 12 patients had relapsed clinically and/or biochemically and 10 patients were dead, of which 2 patients died from prostate cancer. Five-year estimates of BFS, CSS, DFS, and OS rates were 98.5%, 99.3%, 95.6%, and 96.3%, respectively. None of the patients with either Gleason score <8 or with intermediate risk profile had relapsed. The number of HDR-BT treatments was not related to outcome. Despite of age (median, 65.7 years; range, 45.7-77 years) and considerable pretreatment comorbidity in 39 of 275 patients, Genitourinary treatment-related morbidity was moderate with long-lasting Radiation Therapy Oncology Group Grade 2 voiding problems in 26 patients (9.5%) and occasionally mucous discharge in 20 patients (7%), none with Grade >2 for gastrointestinal at follow-up. Complications during implantations were related to pubic arch interference (4 patients) and lithotomy time, causing 2 patients to develop compartment syndrome. Conclusion: Despite still preliminary observations, our 5-year outcome estimates favor the implementation of high-dose-rate brachytherapy in high-risk patients combined with conformal

  4. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-01

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm3 calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  5. High-dose regions versus likelihood of cure after prostate brachytherapy

    SciTech Connect

    Wallner, Kent . E-mail: kent.wallner@med.va.gov; Merrick, Gregory; Sutlief, Steven; True, Laurence; Butler, Wayne

    2005-05-01

    Purpose: To analyze the effect of high-dose regions on biochemical cancer control rates after prostate brachytherapy. Methods and Materials: Patients with 1997 American Joint Committee on Cancer clinical Stage T1c-T2a prostate carcinoma (Gleason grade 5-6, prostate-specific antigen level 4-10 ng/mL) were randomized to implantation with {sup 125}I (144 Gy) vs. {sup 103}Pd (125 Gy, National Institute of Standards and Technology 1999). Isotope implantation was performed by standard techniques, using a modified peripheral loading pattern. Of the 313 patients entered in the protocol, 270 were included in this analysis. The {sup 125}I source strength ranged from 0.4 to 0.89 mCi (median, 0.55 mCi), and the {sup 103}Pd source strength ranged from 1.3 to 1.6 mCi (median, 1.5 mCi). CT was performed within 4 h after implantation. The dosimetric parameters analyzed included the percentage of the postimplant prostate volume covered by the 100%, 150%, 200%, and 300% prescription dose (V{sub 100}, V{sub 150}, V{sub 200}, and V{sub 300}, respectively). The median time to the last follow-up for patients without failure was 2.7 years. Freedom from biochemical failure was defined as a serum prostate-specific antigen level of {<=}0.5 ng/mL at last follow-up. Patients were censored at last follow-up if their serum prostate-specific antigen level was still decreasing. Results: The mean V{sub 100}, V{sub 150}, V{sub 200}, and V{sub 300} value was 90% ({+-}8%), 63% ({+-}14), 35% ({+-}13%), and 14% ({+-}7%), respectively. Patients with a V{sub 100} of {>=}90% had a 3-year freedom from biochemical failure rate of 96% vs. 87% for those with a V{sub 100} of <90% (p = 0.0029). Overall, patients with more high-dose regions had a greater chance of biochemical control. However, when only patients with a V{sub 100} of {>=}90% were analyzed, no relationship was found between higher dose regions and the likelihood of cancer control. This lack of effect on biochemical control was apparent for both

  6. Poor Predictive Value of Intraoperative Real-Time Dosimetry for Prostate Seed Brachytherapy

    SciTech Connect

    Igidbashian, Levon; Donath, David; Carrier, Jean-Francois; Lassalle, Stephanie; Hervieux, Yannick; David, Sandrine; Bahary, Jean-Paul; Taussky, Daniel

    2008-10-01

    Purpose: To identify dosimetric parameters predictive of a good prostate seed I{sup 125} quality implant. We analyzed preimplant and postimplant realtime dosimetry in patients treated with intraoperative (IO) inverse planning. Methods and Materials: We analyzed 127 consecutively treated patients with primarily low-risk prostate carcinoma who underwent prostate permanent seed I{sup 125} brachytherapy using an IO planning approach. The implant was done using the three-dimensional transrectal ultrasound (PRE-TRUS)-guided IO interactive inverse preplanning system. The TRUS was repeated in the operating room after the implant procedure was complete (POST-TRUS). The prostate was recontoured and postimplant dosimetry was calculated. Each patient underwent computed tomography scan on Day 28 (CT-D28) to evaluate implant quality. Area under the receiver operating characteristic curves (AUROC) was evaluated for models predictive of a V100 of {>=}90% and a D90 of {>=}140 Gy on the basis of CT-D28 values. Results: On CT-D28, 72.4% of patients had a V100 of {>=}90% and 74.8% had a D90 of {>=}140 Gy. AUROC for a V100 of {>=}90% was 0.665 (p = 0.004) on PRE-TRUS and 0.619 (p = 0.039) on POST-TRUS. AUROC for D90 of {>=}140 Gy was 0.602 (p = 0.086) on PRE-TRUS and 0.614 (p = 0.054) on POST-TRUS. Using PRE-TRUS V100 cutoff of >97% gives sensitivity of 88% and a false-positive rate of 63%. A POST-TRUS D90 cutoff of >170 Gy resulted in a sensitivity of 62% and a false-positive rate of 34%. Conclusions: Because of unacceptably high false-positive rates, IO preimplant and postimplant TRUS-based dosimetry are not accurate tools to predict for postimplant computed tomography-based dosimetry.

  7. Chemoembolization and stenting combined with iodine-125 seed strands for the treatment of hepatocellular carcinoma with inferior vena cava obstruction

    PubMed Central

    LI, WENHUI; DAI, ZHENYU; YAO, LIZHENG; LUO, JIANJUN; YAN, ZHIPING

    2015-01-01

    The aim of the present study was to investigate the efficacy and safety of stenting combined with radioactive iodine-125 seed strands following chemoembolization for the treatment of patients with hepatocellular carcinoma and inferior vena cava (IVC) obstruction. A retrospective analysis was conducted of 52 hepatocellular carcinoma patients with IVC obstruction. All patients received chemoembolization of tumor-supplying arteries and IVC stents, and 18 patients additionally received iodine-125 seed strands, which were fixed to the stents. Improvement of IVC obstruction and the tumor response rates were compared between the two groups with a median follow-up time of 2.5 months. In both groups the stents were successfully deployed. At the 2-month post-procedural follow-up, the mean diameter of the IVC obstruction site, the mean pressure difference between the distal IVC obstructive segment and the right atrium as well as the obstruction scoring did not differ significantly between the two groups. By contrast, the tumor response rate of the iodine-125 seed strand group was 94.4%, whereas for the group without iodine-125 seed strands it was 35.3% (P<0.001). The combination of stent and iodine-125 seed strands was effective and safe for the treatment of hepatocellular carcinoma with IVC obstruction. PMID:26622424

  8. Radioimmunoguided surgery using iodine 125 B72. 3 in patients with colorectal cancer

    SciTech Connect

    Cohen, A.M.; Martin, E.W. Jr.; Lavery, I.; Daly, J.; Sardi, A.; Aitken, D.; Bland, K.; Mojzisik, C.; Hinkle, G. )

    1991-03-01

    Preliminary data using B72.3 murine monoclonal antibody labeled with iodine 125 suggested that both clinically apparent as well as occult sites of colorectal cancer could be identified intraoperatively using a hand-held gamma detecting probe. We report the preliminary data of a multicenter trial of this approach in patients with primary or recurrent colorectal cancer. One hundred four patients with primary, suspected, or known recurrent colorectal cancer received an intravenous infusion of 1 mg of B72.3 monoclonal antibody radiolabeled with 7.4 x 10 Bq of iodine 125. Twenty-six patients with primary colorectal cancer and 72 patients with recurrent colorectal cancer were examined. Using the gamma detecting probe, 78% of the patients had localization of the antibody in their tumor; this included 75% of primary tumor sites and 63% of all recurrent tumor sites; 9.2% of all tumor sites identified represented occult sites detected only with the gamma detecting probe. The overall sensitivity was 77% and a predictive value of a positive detection was 78%. A total of 30 occult sites in 26 patients were identified. In patients with recurrent cancer, the antibody study provided unique data that precluded resection in 10 patients, and in another eight patients it extended the potentially curative procedure.

  9. Effect of Family History on Outcomes in Patients Treated With Definitive Brachytherapy for Clinically Localized Prostate Cancer

    SciTech Connect

    Peters, Christopher A. Stock, Richard G.; Blacksburg, Seth R.; Stone, Nelson N.

    2009-01-01

    Purpose: To determine the impact familial prostate cancer has on prognosis in men treated with brachytherapy for clinically localized prostate cancer. Methods and Materials: A total of 1,738 consecutive patients with prostate cancer (cT1-3, N0/X, M0) received low-dose-rate brachytherapy alone or in combination with external beam radiation therapy or hormone ablation from 1992 to 2005. The primary end-point was freedom from biochemical failure (FFBF) using the Phoenix definition. Minimum follow-up was 2 years and the median follow-up was 60 months (range, 24-197 months). Results: A total of 187 of 1,738 men (11%) had a family history of prostate cancer in a first-degree relative. For the low-risk patients, both groups had similar actuarial 5-year FFBF (97.2% vs. 95.5%, p = 0.516). For intermediate-risk patients, there was a trend toward improved biochemical control in men positive for family history (5-yr FFBF 100% vs. 93.6%, p = 0.076). For the high-risk patients, men with a positive family history had similar 5-year FFBF (92.8% vs. 85.2%, p = 0.124). On multivariate analysis, family history was not significant; use of hormones, high biologic effective dose, initial prostate-specific antigen value, and Gleason score were the significant variables predicting biochemical control. Conclusions: This is the first study to examine the relationship of familial prostate cancer and outcomed in men treated with brachytherapy alone or in combination therapy. Men with a positive family history have clinicopathologic characteristics and biochemical outcomes similar to those with sporadic disease.

  10. Race and Survival Following Brachytherapy-Based Treatment for Men With Localized or Locally Advanced Adenocarcinoma of the Prostate

    SciTech Connect

    Winkfield, Karen M.; Chen Minghui; Dosoretz, Daniel E.; Salenius, Sharon A.; Katin, Michael; Ross, Rudi; D'Amico, Anthony V.

    2011-11-15

    Purpose: We investigated whether race was associated with risk of death following brachytherapy-based treatment for localized prostate cancer, adjusting for age, cardiovascular comorbidity, treatment, and established prostate cancer prognostic factors. Methods: The study cohort was composed of 5,360 men with clinical stage T1-3N0M0 prostate cancer who underwent brachytherapy-based treatment at 20 centers within the 21st Century Oncology consortium. Cox regression multivariable analysis was used to evaluate the risk of death in African-American and Hispanic men compared to that in Caucasian men, adjusting for age, pretreatment prostate-specific antigen (PSA) level, Gleason score, clinical T stage, year and type of treatment, median income, and cardiovascular comorbidities. Results: After a median follow-up of 3 years, there were 673 deaths. African-American and Hispanic races were significantly associated with an increased risk of all-cause mortality (ACM) (adjusted hazard ratio, 1.77 and 1.79; 95% confidence intervals, 1.3-2.5 and 1.2-2.7; p < 0.001 and p = 0.005, respectively). Other factors significantly associated with an increased risk of death included age (p < 0.001), Gleason score of 8 to 10 (p = 0.04), year of brachytherapy (p < 0.001), and history of myocardial infarction treated with stent or coronary artery bypass graft (p < 0.001). Conclusions: After adjustment for prostate cancer prognostic factors, age, income level, and revascularized cardiovascular comorbidities, African-American and Hispanic races were associated with higher ACM in men with prostate cancer. Additional causative factors need to be identified.

  11. DNA Ploidy Measured on Archived Pretreatment Biopsy Material May Correlate With Prostate-Specific Antigen Recurrence After Prostate Brachytherapy

    SciTech Connect

    Keyes, Mira; MacAulay, Calum; Hayes, Malcolm; Korbelik, Jagoda; Morris, W. James; Palcic, Branko

    2013-08-01

    Purpose: To explore whether DNA ploidy of prostate cancer cells determined from archived transrectal ultrasound-guided biopsy specimens correlates with disease-free survival. Methods and Materials: Forty-seven failures and 47 controls were selected from 1006 consecutive low- and intermediate-risk patients treated with prostate {sup 125}I brachytherapy (July 1998-October 2003). Median follow-up was 7.5 years. Ten-year actuarial disease-free survival was 94.1%. Controls were matched using age, initial prostate-specific antigen level, clinical stage, Gleason score, use of hormone therapy, and follow-up (all P nonsignificant). Seventy-eight specimens were successfully processed; 27 control and 20 failure specimens contained more than 100 tumor cells were used for the final analysis. The Feulgen-Thionin stained cytology samples from archived paraffin blocks were used to determine the DNA ploidy of each tumor by measuring integrated optical densities. Results: The samples were divided into diploid and aneuploid tumors. Aneuploid tumors were found in 16 of 20 of the failures (80%) and 8 of 27 controls (30%). Diploid DNA patients had a significantly lower rate of disease recurrence (P=.0086) (hazard ratio [HR] 0.256). On multivariable analysis, patients with aneuploid tumors had a higher prostate-specific antigen failure rate (HR 5.13). Additionally, those with “excellent” dosimetry (V100 >90%; D90 >144 Gy) had a significantly lower recurrence rate (HR 0.25). All patients with aneuploid tumors and dosimetry classified as “nonexcellent” (V100 <90%; D90 <144 Gy) (5 of 5) had disease recurrence, compared with 40% of patients with aneuploid tumors and “excellent” dosimetry (8 of 15). In contrast, dosimetry did not affect the outcome for diploid patients. Conclusions: Using core biopsy material from archived paraffin blocks, DNA ploidy correctly classified the majority of failures and nonfailures in this study. The results suggest that DNA ploidy can be used as a

  12. Health-Related Quality of Life 2 Years After Treatment With Radical Prostatectomy, Prostate Brachytherapy, or External Beam Radiotherapy in Patients With Clinically Localized Prostate Cancer

    SciTech Connect

    Ferrer, Montserrat Suarez, Jose Francisco; Guedea, Ferran; Fernandez, Pablo; Macias, Victor; Marino, Alfonso; Hervas, Asuncion; Herruzo, Ismael; Ortiz, Maria Jose; Villavicencio, Humberto; Craven-Bratle, Jordi; Garin, Olatz; Aguilo, Ferran

    2008-10-01

    Purpose: To compare treatment impact on health-related quality of life (HRQL) in patients with localized prostate cancer, from before treatment to 2 years after the intervention. Methods and Materials: This was a longitudinal, prospective study of 614 patients with localized prostate cancer treated with radical prostatectomy (134), three-dimensional external conformal radiotherapy (205), and brachytherapy (275). The HRQL questionnaires administered before and after treatment (months 1, 3, 6, 12, and 24) were the Medical Outcomes Study 36-Item Short Form, the Functional Assessment of Cancer Therapy (General and Prostate Specific), the Expanded Prostate Cancer Index Composite (EPIC), and the American Urological Association Symptom Index. Differences between groups were tested by analysis of variance and within-group changes by univariate repeated-measures analysis of variance. Generalized estimating equations (GEE) models were constructed to assess between-group differences in HRQL at 2 years of follow-up after adjusting for clinical variables. Results: In each treatment group, HRQL initially deteriorated after treatment with subsequent partial recovery. However, some dimension scores were still significantly lower after 2 years of treatment. The GEE models showed that, compared with the brachytherapy group, radical prostatectomy patients had worse EPIC sexual summary and urinary incontinence scores (-20.4 and -14.1; p < 0.001), and external radiotherapy patients had worse EPIC bowel, sexual, and hormonal summary scores (-3.55, -5.24, and -1.94; p < 0.05). Prostatectomy patients had significantly better EPIC urinary irritation scores than brachytherapy patients (+4.16; p < 0.001). Conclusions: Relevant differences between treatment groups persisted after 2 years of follow-up. Radical prostatectomy had a considerable negative effect on sexual functioning and urinary continence. Three-dimensional conformal radiotherapy had a moderate negative impact on bowel

  13. Salvage brachytherapy in combination with interstitial hyperthermia for locally recurrent prostate carcinoma following external beam radiation therapy: a prospective phase II study

    PubMed Central

    Strnad, Vratislav; Stauffer, Paul; Dąbrowski, Tomasz; Hetnał, Marcin; Nahajowski, Damian; Walasek, Tomasz; Brandys, Piotr; Matys, Robert

    2015-01-01

    Optimal treatment for patients with only local prostate cancer recurrence after external beam radiation therapy (EBRT) failure remains unclear. Possible curative treatments are radical prostatectomy, cryosurgery, and brachytherapy. Several single institution series proved that high-dose-rate brachytherapy (HDRBT) and pulsed-dose-rate brachytherapy (PDRBT) are reasonable options for this group of patients with acceptable levels of genitourinary and gastrointestinal toxicity. A standard dose prescription and scheme have not been established yet, and the literature presents a wide range of fractionation protocols. Furthermore, hyperthermia has shown the potential to enhance the efficacy of re-irradiation. Consequently, a prospective trial is urgently needed to attain clear structured prospective data regarding the efficacy of salvage brachytherapy with adjuvant hyperthermia for locally recurrent prostate cancer. The purpose of this report is to introduce a new prospective phase II trial that would meet this need. The primary aim of this prospective phase II study combining Iridium-192 brachytherapy with interstitial hyperthermia (IHT) is to analyze toxicity of the combined treatment; a secondary aim is to define the efficacy (bNED, DFS, OS) of salvage brachytherapy. The dose prescribed to PTV will be 30 Gy in 3 fractions for HDRBT, and 60 Gy in 2 fractions for PDRBT. During IHT, the prostate will be heated to the range of 40–47°C for 60 minutes prior to brachytherapy dose delivery. The protocol plans for treatment of 77 patients. PMID:26207116

  14. Maximum vs. Mono Androgen Blockade and the Risk of Recurrence in Men With Localized Prostate Cancer Undergoing Brachytherapy

    SciTech Connect

    Chen, Ronald C. Sadetsky, Natalia; Chen, M.-H.; Carroll, Peter R.; D'Amico, Anthony V.

    2009-09-01

    Purpose: We examined whether maximum androgen blockade (MAB) is associated with a decreased recurrence risk vs. single-agent androgen suppression (monotherapy) for men undergoing brachytherapy (BT) for localized prostate cancer. Methods and Materials: Data from 223 men in Cancer of the Prostate Strategic Urologic Research Endeavor database who received androgen deprivation therapy (ADT) concurrent with BT for intermediate- or high-risk prostatic adenocarcinoma were included; 159 (71%) received MAB, and 64 (29%) monotherapy (luteinizing hormone-releasing hormone agonist or anti-androgen alone). Cox regression analysis was performed to assess whether the choice of ADT was associated with disease recurrence adjusting for known prognostic factors. Results: Men who received MAB had similar Gleason scores, T categories, and pretreatment prostate-specific antigen as those who received monotherapy. After a median follow-up of 49 months, the use of MAB was not associated with a decrease in the risk recurrence (p = 0.72), after adjusting for known prognostic factors. A higher PSA at diagnosis (p = 0.03) and younger age at diagnosis (p < 0.01) were associated with increased recurrence risk. The 3-year recurrence free survival was 76% for patients in both monotherapy and MAB groups. Conclusions: There are varied practice patterns in physicians' choice of the extent of concurrent ADT when used with brachytherapy for men with intermediate- or high-risk prostate cancer. Given a lack of demonstrated superiority from either ADT choice, both appear to be reasonable options.

  15. In vivo motion and force measurement of surgical needle intervention during prostate brachytherapy

    SciTech Connect

    Podder, Tarun; Clark, Douglas; Sherman, Jason; Fuller, Dave; Messing, Edward; Rubens, Deborah; Strang, John; Brasacchio, Ralph; Liao, Lydia; Ng, W.-S.; Yu Yan

    2006-08-15

    In this paper, we present needle insertion forces and motion trajectories measured during actual brachytherapy needle insertion while implanting radioactive seeds in the prostate glands of 20 different patients. The needle motion was captured using ultrasound images and a 6 degree-of-freedom electromagnetic-based position sensor. Needle velocity was computed from the position information and the corresponding time stamps. From in vivo data we found the maximum needle insertion forces to be about 15.6 and 8.9 N for 17 gauge (1.47 mm) and 18 gauge (1.27 mm) needles, respectively. Part of this difference in insertion forces is due to the needle size difference (17G and 18G) and the other part is due to the difference in tissue properties that are specific to the individual patient. Some transverse forces were observed, which are attributed to several factors such as tissue heterogeneity, organ movement, human factors in surgery, and the interaction between the template and the needle. However, theses insertion forces are significantly responsible for needle deviation from the desired trajectory and target movement. Therefore, a proper selection of needle and modulated velocity (translational and rotational) may reduce the tissue deformation and target movement by reducing insertion forces and thereby improve the seed delivery accuracy. The knowledge gleaned from this study promises to be useful for not only designing mechanical/robotic systems but also developing a predictive deformation model of the prostate and real-time adaptive controlling of the needle.

  16. MRI of prostate brachytherapy seeds at high field: A study in phantom

    SciTech Connect

    Thomas, S. D.; Wachowicz, K.; Fallone, B. G.

    2009-11-15

    Postimplant evaluation of prostate brachytherapy using magnetic resonance imaging (MRI) at 1.5 T has met with some difficulties due to the uncertainty associated with seed localization despite the excellent anatomical delineation this imaging modality can achieve. Seeds in vascularized regions or outside the prostate, where signal heterogeneity or drop off can obscure their position, can be difficult to identify. The increase in SNR available at 3.0 T offers the potential to improve these issues with visualization. However, before moving directly to in vivo studies, it is important to investigate the effects of artifact size on the ability to localize multiple seeds in close proximity. These artifacts are of extra concern at higher field because of the increased induced field distortions surrounding the seeds. A single prostate brachytherapy seed (IMC6711, OncoSeed) and arrays of seed pairs were suspended in a porcine gel medium and imaged on 1.5 and 3 T MRI scanners for comparison. Two basic acquisition techniques utilized in a wide array of clinical sequences [spin-echo based and gradient-echo (GE) based] were investigated for the types of artifacts they produce, and their dependence on field. Analysis of the resulting voids was performed to determine the relative size of seeds as seen on the images, as well as the ability to distinguish seeds at close proximity. The seed voids at 3 T were only slightly larger than those obtained at 1.5 T (0.5 mm longer and wider) when using a spin-echo type sequence. For this work, the authors used a proton density fast spin-echo (FSE) sequence. These results are promising for the use of 3 T imaging for postimplant evaluation since the SNR will increase by roughly a factor of 2 with only a limited corresponding increase in artifact size. The minimum separation of the seeds to be completely distinguished using void analysis increased from between 1.5 and 3 mm to between 3 and 4.5 mm when going from 1.5 to 3 T FSE imaging. The

  17. An automated optimization tool for high-dose-rate (HDR) prostate brachytherapy with divergent needle pattern.

    PubMed

    Borot de Battisti, M; Maenhout, M; Denis de Senneville, B; Hautvast, G; Binnekamp, D; Lagendijk, J J W; van Vulpen, M; Moerland, M A

    2015-10-01

    Focal high-dose-rate (HDR) for prostate cancer has gained increasing interest as an alternative to whole gland therapy as it may contribute to the reduction of treatment related toxicity. For focal treatment, optimal needle guidance and placement is warranted. This can be achieved under MR guidance. However, MR-guided needle placement is currently not possible due to space restrictions in the closed MR bore. To overcome this problem, a MR-compatible, single-divergent needle-implant robotic device is under development at the University Medical Centre, Utrecht: placed between the legs of the patient inside the MR bore, this robot will tap the needle in a divergent pattern from a single rotation point into the tissue. This rotation point is just beneath the perineal skin to have access to the focal prostate tumor lesion. Currently, there is no treatment planning system commercially available which allows optimization of the dose distribution with such needle arrangement. The aim of this work is to develop an automatic inverse dose planning optimization tool for focal HDR prostate brachytherapy with needle insertions in a divergent configuration. A complete optimizer workflow is proposed which includes the determination of (1) the position of the center of rotation, (2) the needle angulations and (3) the dwell times. Unlike most currently used optimizers, no prior selection or adjustment of input parameters such as minimum or maximum dose or weight coefficients for treatment region and organs at risk is required. To test this optimizer, a planning study was performed on ten patients (treatment volumes ranged from 8.5 cm(3)to 23.3 cm(3)) by using 2-14 needle insertions. The total computation time of the optimizer workflow was below 20 min and a clinically acceptable plan was reached on average using only four needle insertions. PMID:26378657

  18. An automated optimization tool for high-dose-rate (HDR) prostate brachytherapy with divergent needle pattern

    NASA Astrophysics Data System (ADS)

    Borot de Battisti, M.; Maenhout, M.; de Senneville, B. Denis; Hautvast, G.; Binnekamp, D.; Lagendijk, J. J. W.; van Vulpen, M.; Moerland, M. A.

    2015-10-01

    Focal high-dose-rate (HDR) for prostate cancer has gained increasing interest as an alternative to whole gland therapy as it may contribute to the reduction of treatment related toxicity. For focal treatment, optimal needle guidance and placement is warranted. This can be achieved under MR guidance. However, MR-guided needle placement is currently not possible due to space restrictions in the closed MR bore. To overcome this problem, a MR-compatible, single-divergent needle-implant robotic device is under development at the University Medical Centre, Utrecht: placed between the legs of the patient inside the MR bore, this robot will tap the needle in a divergent pattern from a single rotation point into the tissue. This rotation point is just beneath the perineal skin to have access to the focal prostate tumor lesion. Currently, there is no treatment planning system commercially available which allows optimization of the dose distribution with such needle arrangement. The aim of this work is to develop an automatic inverse dose planning optimization tool for focal HDR prostate brachytherapy with needle insertions in a divergent configuration. A complete optimizer workflow is proposed which includes the determination of (1) the position of the center of rotation, (2) the needle angulations and (3) the dwell times. Unlike most currently used optimizers, no prior selection or adjustment of input parameters such as minimum or maximum dose or weight coefficients for treatment region and organs at risk is required. To test this optimizer, a planning study was performed on ten patients (treatment volumes ranged from 8.5 cm3to 23.3 cm3) by using 2-14 needle insertions. The total computation time of the optimizer workflow was below 20 min and a clinically acceptable plan was reached on average using only four needle insertions.

  19. SU-C-16A-05: OAR Dose Tolerance Recommendations for Prostate and Cervical HDR Brachytherapy: Dose Versus Volume Metrics

    SciTech Connect

    Geneser, S; Cunha, J; Pouliot, J; Hsu, I

    2014-06-15

    Purpose: HDR brachytherapy consensus dose tolerance recommendations for organs at risk (OARs) remain widely debated. Prospective trials reporting metrics must be sufficiently data-dense to assess adverse affects and identify optimally predictive tolerances. We explore the tradeoffs between reporting dose-metrics versus volume-metrics and the potential impact on trial outcome analysis and tolerance recommendations. Methods: We analyzed 26 prostate patients receiving 15 Gy HDR single-fraction brachytherapy boost to 45 Gy external beam radiation therapy and 28 cervical patients receiving 28 Gy HDR brachytherapy monotherapy in 4 fractions using 2 implants. For each OAR structure, a robust linear regression fit was performed for the dose-metrics as a function of the volume-metrics. The plan quality information provided by recommended dose-metric and volume-metric values were compared. Results: For prostate rectal dose, D2cc and V75 lie close to the regression line, indicating they are similarly informative. Two outliers for prostate urethral dose are substantially different from the remaining cohort in terms of D0.1cc and V75, but not D1cc, suggesting the choice of reporting dose metric is essential. For prostate bladder and cervical bladder, rectum, and bowel, dose outliers are more apparent via V75 than recommended dose-metrics. This suggests that for prostate bladder dose and all cervical OAR doses, the recommended volume-metrics may be better predictors of clinical outcome than dose-metrics. Conclusion: For plan acceptance criteria, dose and volume-metrics are reciprocally equivalent. However, reporting dosemetrics or volume-metrics alone provides substantially different information. Our results suggest that volume-metrics may be more sensitive to differences in planned dose, and if one metric must be chosen, volumemetrics are preferable. However, reporting discrete DVH points severely limits the ability to identify planning tolerances most predictive of adverse

  20. Dwell time modulation restrictions do not necessarily improve treatment plan quality for prostate HDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Balvert, Marleen; Gorissen, Bram L.; den Hertog, Dick; Hoffmann, Aswin L.

    2015-01-01

    Inverse planning algorithms for dwell time optimisation in interstitial high-dose-rate (HDR) brachytherapy may produce solutions with large dwell time variations within catheters, which may result in undesirable selective high-dose subvolumes. Extending the dwell time optimisation model with a dwell time modulation restriction (DTMR) that limits dwell time differences between neighboring dwell positions has been suggested to eliminate this problem. DTMRs may additionally reduce the sensitivity for uncertainties in dwell positions that inevitably result from catheter reconstruction errors and afterloader source positioning inaccuracies. This study quantifies the reduction of high-dose subvolumes and the robustness against these uncertainties by applying a DTMR to template-based prostate HDR brachytherapy implants. Three different DTMRs were consecutively applied to a linear dose-based penalty model (LD) and a dose-volume based model (LDV), both obtained from literature. The models were solved with DTMR levels ranging from no restriction to uniform dwell times within catheters in discrete steps. Uncertainties were simulated on clinical cases using in-house developed software, and dose-volume metrics were calculated in each simulation. For the assessment of high-dose subvolumes, the dose homogeneity index (DHI) and the contiguous dose volume histogram were analysed. Robustness was measured by the improvement of the lowest D90% of the planning target volume (PTV) observed in the simulations. For (LD), a DTMR yields an increase in DHI of approximately 30% and reduces the size of the largest high-dose volume by 2-5 cc. However, this comes at a cost of a reduction in D90% of the PTV of 10%, which often implies that it drops below the desired minimum of 100%. For (LDV), none of the DTMRs were able to improve high-dose volume measures. DTMRs were not capable of improving robustness of PTV D90% against uncertainty in dwell positions for both models.

  1. Long-Term Efficacy and Toxicity of Low-Dose-Rate {sup 125}I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

    SciTech Connect

    Kittel, Jeffrey A.; Reddy, Chandana A.; Smith, Kristin L.; Stephans, Kevin L.; Tendulkar, Rahul D.; Ulchaker, James; Angermeier, Kenneth; Campbell, Steven; Stephenson, Andrew; Klein, Eric A.; Wilkinson, D. Allan; Ciezki, Jay P.

    2015-07-15

    Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with {sup 125}I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy.

  2. WE-A-17A-11: Implanted Brachytherapy Seed Movement Due to Transrectal Ultrasound Probe-Induced Prostate Deformation

    SciTech Connect

    Liu, D; Usmani, N; Sloboda, R; Meyer, T; Husain, S; Angyalfi, S; Kay, I

    2014-06-15

    Purpose: To characterize the movement of implanted brachytherapy seeds due to transrectal ultrasound probe-induced prostate deformation and to estimate the effects on prostate dosimetry. Methods: Implanted probe-in and probe-removed seed distributions were reconstructed for 10 patients using C-arm fluoroscopy imaging. The prostate was delineated on ultrasound and registered to the fluoroscopy seeds using a visible subset of seeds and residual needle tracks. A linear tensor and shearing model correlated the seed movement with position. The seed movement model was used to infer the underlying prostate deformation and to simulate the prostate contour without probe compression. Changes in prostate and surrogate urethra dosimetry were calculated. Results: Seed movement patterns reflecting elastic decompression, lateral shearing, and rectal bending were observed. Elastic decompression was characterized by anterior-posterior expansion and superior-inferior and lateral contractions. For lateral shearing, anterior movement up to 6 mm was observed for extraprostatic seeds in the lateral peripheral region. The average intra-prostatic seed movement was 1.3 mm, and the residual after linear modeling was 0.6 mm. Prostate D90 increased by 4 Gy on average (8 Gy max) and was correlated with elastic decompression. For selected patients, lateral shearing resulted in differential change in D90 of 7 Gy between anterior and posterior quadrants, and increase in whole prostate D90 of 4 Gy. Urethra D10 increased by 4 Gy. Conclusion: Seed movement upon probe removal was characterized. The proposed model captured the linear correlation between seed movement and position. Whole prostate dose coverage increased slightly, due to the small but systematic seed movement associated with elastic decompression. Lateral shearing movement increased dose coverage in the anterior-lateral region, at the expense of the posterior-lateral region. The effect on whole prostate D90 was smaller due to the subset

  3. Health-Related Quality of Life up to Six Years After {sup 125}I Brachytherapy for Early-Stage Prostate Cancer

    SciTech Connect

    Roeloffzen, Ellen M.A.; Lips, Irene M.; Gellekom, Marion P.R. van; Roermund, Joep van; Frank, Steven J.; Battermann, Jan J.; Vulpen, Marco van

    2010-03-15

    Purpose: Health-related quality of life (HRQOL) after prostate brachytherapy has been extensively described in published reports but hardly any long-term data are available. The aim of the present study was to prospectively assess long-term HRQOL 6 years after {sup 125}I prostate brachytherapy. Methods and Materials: A total of 127 patients treated with {sup 125}I brachytherapy for early-stage prostate cancer between December 2000 and June 2003 completed a HRQOL questionnaire at five time-points: before treatment and 1 month, 6 months, 1 year, and 6 years after treatment. The questionnaire included the RAND-36 generic health survey, the cancer-specific European Organization for Research and Treatment of Cancer core questionnaire (EORTCQLQ-C30), and the tumor-specific EORTC prostate cancer module (EORTC-PR25). A change in a score of >=10 points was considered clinically relevant. Results: Overall, the HRQOL at 6 years after {sup 125}I prostate brachytherapy did not significantly differ from baseline. Although a statistically significant deterioration in HRQOL at 6 years was seen for urinary symptoms, bowel symptoms, pain, physical functioning, and sexual activity (p <.01), most changes were not clinically relevant. A statistically significant improvement at 6 years was seen for mental health, emotional functioning, and insomnia (p <.01). The only clinically relevant changes were seen for emotional functioning and sexual activity. Conclusion: This is the first study presenting prospective HRQOL data up to 6 years after {sup 125}I prostate brachytherapy. HRQOL scores returned to approximately baseline values at 1 year and remained stable up to 6 years after treatment. {sup 125}I prostate brachytherapy did not adversely affect patients' long-term HRQOL.

  4. Matched-pair analysis and dosimetric variations of two types of software for interstitial permanent brachytherapy for prostate cancer

    SciTech Connect

    Ishiyama, Hiromichi; Nakamura, Ryuji; Satoh, Takefumi; Tanji, Susumu; Teh, Bin S.; Uemae, Mineko; Baba, Shiro; Hayakawa, Kazushige

    2012-04-01

    The purpose of this study was to determine whether identical dosimetric results could be achieved using different planning software for permanent interstitial brachytherapy for prostate cancer. Data from 492 patients treated with brachytherapy were used for matched-pair analysis. Interplant and Variseed were used as software for ultrasound-based treatment planning. Institution, neoadjuvant hormonal therapy, prostate volume, and source strength were used for factors to match the 2 groups. The study population comprised of 126 patients with treatment planning using Interplant software and 127 matched patients using Variseed software. Dosimetric results were compared between the 2 groups. The Variseed group showed significantly higher values for dose covering 90% of prostate volume (pD90), prostate volume covered by 150% of prescription dose (pV150), and dose covering 30% of the urethra (uD30) compared with the Interplant group. Our results showed that use of different software could lead to different dosimetric results, which might affect the clinical outcomes.

  5. A Prospective Quasi-Randomized Comparison of Intraoperatively Built Custom-Linked Seeds Versus Loose Seeds for Prostate Brachytherapy

    SciTech Connect

    Ishiyama, Hiromichi; Satoh, Takefumi; Kawakami, Shogo; Tsumura, Hideyasu; Komori, Shouko; Tabata, Ken-ichi; Sekiguchi, Akane; Takahashi, Ryo; Soda, Itaru; Takenaka, Kouji; Iwamura, Masatsugu; Hayakawa, Kazushige

    2014-09-01

    Purpose: To compare dosimetric parameters, seed migration rates, operation times, and acute toxicities of intraoperatively built custom-linked (IBCL) seeds with those of loose seeds for prostate brachytherapy. Methods and Materials: Participants were 140 patients with low or intermediate prostate cancer prospectively allocated to an IBCL seed group (n=74) or a loose seed group (n=66), using quasirandomization (allocated by week of the month). All patients underwent prostate brachytherapy using an interactive plan technique. Computed tomography and plain radiography were performed the next day and 1 month after brachytherapy. The primary endpoint was detection of a 5% difference in dose to 90% of prostate volume on postimplant computed tomography 1 month after treatment. Seed migration was defined as a seed position >1 cm from the cluster of other seeds on radiography. A seed dropped into the seminal vesicle was also defined as a migrated seed. Results: Dosimetric parameters including the primary endpoint did not differ significantly between groups, but seed migration rate was significantly lower in the IBCL seed group (0%) than in the loose seed group (55%; P<.001). Mean operation time was slightly but significantly longer in the IBCL seed group (57 min) than in the loose seed group (50 min; P<.001). No significant differences in acute toxicities were seen between groups (median follow-up, 9 months). Conclusions: This prospective quasirandomized control trial showed no dosimetric differences between IBCL seed and loose seed groups. However, a strong trend toward decreased postimplant seed migration was shown in the IBCL seed group.

  6. Isotope and Patient Age Predict for PSA Spikes After Permanent Prostate Brachytherapy

    SciTech Connect

    Bostancic, Chelsea; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah; Galbreath, Robert; Lief, Jonathan; Gutman, Sarah E.

    2007-08-01

    Purpose: To evaluate prostate-specific antigen (PSA) spikes after permanent prostate brachytherapy in low-risk patients. Methods and Materials: The study population consisted of 164 prostate cancer patients who were part of a prospective randomized trial comparing {sup 103}Pd and {sup 125}I for low-risk disease. Of the 164 patients, 61 (37.2%) received short-course androgen deprivation therapy. The median follow-up was 5.4 years. On average, 11.1 post-treatment PSA measurements were obtained per patient. Biochemical disease-free survival was defined as a PSA level of {<=}0.40 ng/mL after nadir. A PSA spike was defined as an increase of {>=}0.2 ng/mL, followed by a durable decline to prespike levels. Multiple parameters were evaluated as predictors for a PSA spike. Results: Of the 164 patients, 44 (26.9%) developed a PSA spike. Of the 46 hormone-naive {sup 125}I patients and 57 hormone-naive {sup 103}Pd patients, 21 (45.7%) and 8 (14.0%) developed a PSA spike. In the hormone-naive patients, the mean time between implantation and the spike was 22.6 months and 18.7 months for {sup 125}I and {sup 103}Pd, respectively. In patients receiving neoadjuvant androgen deprivation therapy, the incidence of spikes was comparable between isotopes ({sup 125}I 28.1% and {sup 103}Pd 20.7%). The incidence of spikes was substantially different in patients <65 years vs. {>=}65 years old (38.5% vs. 16.3%). On multivariate Cox regression analysis, patient age (p < 0.001) and isotope (p = 0.002) were significant predictors for spike. Conclusion: In low-risk prostate cancer, PSA spikes are most common in patients implanted with {sup 125}I and/or <65 years of age. Differences in isotope-related spikes are most pronounced in hormone-naive patients.

  7. Urethra-Sparing, Intraoperative, Real-Time Planned, Permanent-Seed Prostate Brachytherapy: Toxicity Analysis

    SciTech Connect

    Zilli, Thomas; Taussky, Daniel; Donath, David; Le, Hoa Phong; Larouche, Renee-Xaviere; Beliveau-Nadeau, Dominique; Hervieux, Yannick; Delouya, Guila

    2011-11-15

    Purpose: To report the toxicity outcome in patients with localized prostate cancer undergoing {sup 125}I permanent-seed brachytherapy (BT) according to a urethra-sparing, intraoperative (IO), real-time planned conformal technique. Methods and Materials: Data were analyzed on 250 patients treated consecutively for low- or intermediate-risk prostate cancer between 2005 and 2009. The planned goal was urethral V{sub 150} = 0. Acute and late genitourinary (GU), gastrointestinal (GI), and erectile toxicities were scored with the International Prostate Symptom Score (IPSS) questionnaire and Common Terminology Criteria for Adverse Events (version 3.0). Median follow-up time for patients with at least 2 years of follow-up (n = 130) was 34.4 months (range, 24-56.9 months). Results: Mean IO urethra V{sub 150} was 0.018% {+-} 0.08%. Mean prostate D{sub 90} and V{sub 100} on day-30 computed tomography scan were 158.0 {+-} 27.0 Gy and 92.1% {+-} 7.2%, respectively. Mean IPSS peak was 9.5 {+-} 6.3 1 month after BT (mean difference from baseline IPSS, 5.3). No acute GI toxicity was observed in 86.8% of patients. The 3-year probability of Grade {>=}2 late GU toxicity-free survival was 77.4% {+-} 4.0%, with Grade 3 late GU toxicity encountered in only 3 patients. Three-year Grade 1 late GI toxicity-free survival was 86.1% {+-} 3.2%. No patient presented Grade {>=}2 late GI toxicity. Of patients with normal sexual status at baseline, 20.7% manifested Grade {>=}2 erectile dysfunction after BT. On multivariate analysis, elevated baseline IPSS (p = 0.016) and high-activity sources (median 0.61 mCi) (p = 0.033) predicted increased Grade {>=}2 late GU toxicity. Conclusions: Urethra-sparing IO BT results in low acute and late GU toxicity compared with the literature. High seed activity and elevated IPSS at baseline increased long-term GU toxicity.

  8. SU-E-J-181: Effect of Prostate Motion On Combined Brachytherapy and External Beam Dose Based On Daily Motion of the Prostate

    SciTech Connect

    Narayana, V; McLaughlin, P; Ealbaj, J

    2015-06-15

    Purpose: In this study, the adequacy of target expansions on the combined external beam and implant dose was examined based on the measured daily motion of the prostate. Methods: Thirty patients received an I–125 prostate implant prescribed to dose of 90Gy. This was followed by external beam to deliver a dose of 90Gyeq (external beam equivalent) to the prostate over 25 to 30 fractions. An ideal IMRT plan was developed by optimizing the external beam dose based on the delivered implant dose. The implant dose was converted to an equivalent external beam dose using the linear quadratic model. Patients were set up on the treatment table by daily orthogonal imaging and aligning the marker seeds in the prostate. Orthogonal images were obtained at the end of treatment to assess prostate intrafraction motion. Based on the observed motion of the markers between the initial and final images, 5 individual plans showing the actual dose delivered to the patient were calculated. A final true dose distribution was established based on summing the implant dose and the 5 external beam plans. Dose to the prostate, seminal vesicles, lymphnodes and normal tissues, rectal wall, urethra and lower sphincter were calculated and compared to ideal. On 18 patients who were sexually active, dose to the corpus cavernosum and internal pudendal artery was also calculated. Results: The average prostate motion in 3 orthogonal directions was less than 1 mm with a standard deviation of less than +2 mm. Dose and volume parameters showed that there was no decrease in dose to the targets and a marginal decrease in dose to in normal tissues. Conclusion: Dose delivered by seed implant moves with the prostate, decreasing the impact of intrafractions dose movement on actual dose delivered. Combined brachytherapy and external beam dose delivered to the prostate was not sensitive to prostate motion.

  9. A dosimetric study of prostate brachytherapy using Monte Carlo simulations with a voxel phantom, measurements and a comparison with a treatment planning procedure.

    PubMed

    Teles, P; Barros, S; Cardoso, S; Facure, A; da Rosa, L A R; Santos, M; Pereira, P; Vaz, P; Zankl, M

    2015-07-01

    In prostate brachytherapy treatments, there is an initial swelling of the prostate of the patient due to an oedema related to the insertion of the seeds. The variation of the prostate volume can lead to variations in the final prescribed dose in treatment planning procedures. As such, it is important to understand their influence for dose optimisation purposes. This work reports on a dosimetric study of the swelling of the prostate in prostate brachytherapy using Monte Carlo simulations. Dosimetric measurements performed on a physical anthropomorphic tissue-equivalent prostate phantom and thermoluminescent dosimeters (TLDs) were used to validate the MC model. Finally the MC model was also used to simulate prostate swelling in a real treatment planning procedure. The obtained results indicate that the parameters mentioned above represent a source of uncertainty in dose assessment in prostate brachytherapy, and can be detrimental to a correct dose evaluation in treatment plannings, and that these parameters can be accurately determined by means of MC simulations with a voxel phantom. PMID:25870437

  10. Is a Loose-Seed Nomogram Still Valid for Prostate Brachytherapy in a Stranded-Seed Era?

    SciTech Connect

    Kudchadker, Rajat J.; Swanson, David A.; Kuban, Deborah A.; Lee, Andrew K.; Bruno, Teresa L. C.; Frank, Steven J.

    2008-10-01

    Purpose: To characterize the amount of activity required to treat the prostate with stranded {sup 125}I radioactive seeds and compare our stranded data with the amount of activity recommended when individual seeds are implanted using a Mick applicator. Methods and Materials: Data from two groups of patients at University of Texas M. D. Anderson Cancer Center who were treated with prostate brachytherapy as monotherapy were analyzed. The first group included 100 patients implanted with individual seeds in 2000 and 2001. The second group comprised 81 patients for whom stranded seeds were implanted in 2006 and 2007. Seeds in both groups were {sup 125}I seeds with an air kerma strength of 0.497 U per seed (0.391 mCi per seed). The prescribed dose to planning target volume was 145 Gy. Results: The total implanted activity and the number of seeds used were significantly lower in the second group (p < 0.0001) than in the first group. The reduction in activity in the stranded-seed group was approximately 23% for a 20-cm{sup 3} prostate and approximately 15% for a 60-cm{sup 3} prostate. With equivalent activity between the two groups, the stranded-seed treatment covered a larger treatment volume with the prescribed dose. Conclusions: The amount of activity required to effectively treat a prostate of a given volume was lower with stranded seeds than with loose seeds. Our experience suggests that prostate brachytherapy that uses stranded seeds leads to a more efficient implant with fewer seeds and lower overall activity, resulting in improved homogeneity.

  11. The investigation of prostatic calcifications using μ-PIXE analysis and their dosimetric effect in low dose rate brachytherapy treatments using Geant4.

    PubMed

    Pope, D J; Cutajar, D L; George, S P; Guatelli, S; Bucci, J A; Enari, K E; Miller, S; Siegele, R; Rosenfeld, A B

    2015-06-01

    Low dose rate brachytherapy is a widely used modality for the treatment of prostate cancer. Most clinical treatment planning systems currently in use approximate all tissue to water, neglecting the existence of inhomogeneities, such as calcifications. The presence of prostatic calcifications may perturb the dose due to the higher photoelectric effect cross section in comparison to water. This study quantitatively evaluates the effect of prostatic calcifications on the dosimetric outcome of brachytherapy treatments by means of Monte Carlo simulations and its potential clinical consequences.Four pathological calcification samples were characterised with micro-particle induced x-ray emission (μ-PIXE) to determine their heavy elemental composition. Calcium, phosphorus and zinc were found to be the predominant heavy elements in the calcification composition. Four clinical patient brachytherapy treatments were modelled using Geant4 based Monte Carlo simulations, in terms of the distribution of brachytherapy seeds and calcifications in the prostate. Dose reductions were observed to be up to 30% locally to the calcification boundary, calcification size dependent. Single large calcifications and closely placed calculi caused local dose reductions of between 30-60%. Individual calculi smaller than 0.5 mm in diameter showed minimal dosimetric impact, however, the effects of small or diffuse calcifications within the prostatic tissue could not be determined using the methods employed in the study. The simulation study showed a varying reduction on common dosimetric parameters. D90 showed a reduction of 2-5%, regardless of calcification surface area and volume. The parameters V100, V150 and V200 were also reduced by as much as 3% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications, which may have a significant dosimetric impact on brachytherapy treatment, however, such impacts depend strongly on specific factors

  12. In vivo real-time dosimetric verification in high dose rate prostate brachytherapy

    SciTech Connect

    Seymour, Erin L.; Downes, Simon J.; Fogarty, Gerald B.; Izard, Michael A.; Metcalfe, Peter

    2011-08-15

    Purpose: To evaluate the performance of a diode array in the routine verification of planned dose to points inside the rectum from prostate high dose rate (HDR) brachytherapy using a real-time planning system. Methods: A dosimetric study involving 28 patients was undertaken where measured doses received during treatment were compared to those calculated by the treatment planning system (TPS). After the ultrasound imaging required for treatment planning had been recorded, the ultrasound probe was replaced with a geometric replica that contained an 8 mm diameter cylindrical cavity in which a PTW diode array type 9112 was placed. The replica probe was then positioned inside the rectum with the individual diode positions determined using fluoroscopy. Dose was then recorded during the patients' treatment and compared to associated coordinates in the planning system. Results: Factors influencing diode response and experimental uncertainty were initially investigated to estimate the overall uncertainty involved in dose measurements, which was determined to be {+-}10%. Data was acquired for 28 patients' first fractions, 11 patients' second fractions, and 13 patients' third fractions with collection dependent upon circumstances. Deviations between the diode measurements and predicted values ranged from -42% to +35% with 71% of measurements experiencing less than a 10% deviation from the predicted values. If the {+-}10% measurement uncertainty was combined with a tolerated dose discrepancy of {+-}10% then over 95% of the diode results exhibited agreement with the calculated data to within {+-}20%. It must also be noted that when large dose discrepancies were apparent they did not necessarily occur for all five diodes in the one measurement. Conclusions: This technique provided a method that could be utilized to detect gross errors in dose delivery of a real-time prostate HDR plan. Limitations in the detection system used must be well understood if meaningful results are to

  13. [Conservation of erectile function following brachytherapy for low-risk prostate cancer].

    PubMed

    Gilberti, C; Gallo, F; Chiono, L; Gastaldi, E; Ninotta, G; Rosso, G

    2009-01-01

    Brachytherapy (BT) is an effective option to treat low-risk prostate cancer (CaP). While oncological results are consistent with those reported following radical retropubic prostatectomy (RRP), attention may be given to the advantages in terms of functional results that a less invasive approach can ensure. The aim of this study is to assess the impact of the conservation of erectile function (EF) in patients who underwent BT with a short and medium term follow-up. MATERIALS AND METHODS. Between May 1999 and January 2005, 170 patients underwent BT for low-risk CaP (intracapsular prostate cancer, PSA , 10 ng/mL, Gleason score , 6). Among them, 58 patients (average age 65.6) with good preoperative erectile function (IIEF>22) and a minimum follow-up of 5 years were selected. The results were evaluated by comparing the values of pre- and postoperative IIEF questionnaire at 3 months, 1 and 5 years of medium follow-up. RESULTS. At a mean 3-month follow-up, a spontaneous recovery of EF (IIEF> 17), strongly influenced by urinary irritative disorders, was reported by 34/58 patients (58%). At 1 and 5 years, good EF (IIEF >22) was reported by 45/58 (78%) and 39/58 (68%) patients, respectively. DISCUSSION AND CONCLUSIONS. The recovery of EF was good one year after BT (78%). Urinary disorders are a significant limiting factor on this recovery. The deterioration of EF during the follow-up, which was already described in literature, is due not only to ageing but also to a delayed radioactive effect on pelvic structures.

  14. Deformable registration of x-ray to MRI for post-implant dosimetry in prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Park, Seyoun; Song, Danny Y.; Lee, Junghoon

    2016-03-01

    Post-implant dosimetric assessment in prostate brachytherapy is typically performed using CT as the standard imaging modality. However, poor soft tissue contrast in CT causes significant variability in target contouring, resulting in incorrect dose calculations for organs of interest. CT-MR fusion-based approach has been advocated taking advantage of the complementary capabilities of CT (seed identification) and MRI (soft tissue visibility), and has proved to provide more accurate dosimetry calculations. However, seed segmentation in CT requires manual review, and the accuracy is limited by the reconstructed voxel resolution. In addition, CT deposits considerable amount of radiation to the patient. In this paper, we propose an X-ray and MRI based post-implant dosimetry approach. Implanted seeds are localized using three X-ray images by solving a combinatorial optimization problem, and the identified seeds are registered to MR images by an intensity-based points-to-volume registration. We pre-process the MR images using geometric and Gaussian filtering. To accommodate potential soft tissue deformation, our registration is performed in two steps, an initial affine transformation and local deformable registration. An evolutionary optimizer in conjunction with a points-to-volume similarity metric is used for the affine registration. Local prostate deformation and seed migration are then adjusted by the deformable registration step with external and internal force constraints. We tested our algorithm on six patient data sets, achieving registration error of (1.2+/-0.8) mm in < 30 sec. Our proposed approach has the potential to be a fast and cost-effective solution for post-implant dosimetry with equivalent accuracy as the CT-MR fusion-based approach.

  15. Mixed integer programming improves comprehensibility and plan quality in inverse optimization of prostate HDR brachytherapy.

    PubMed

    Gorissen, Bram L; den Hertog, Dick; Hoffmann, Aswin L

    2013-02-21

    Current inverse treatment planning methods that optimize both catheter positions and dwell times in prostate HDR brachytherapy use surrogate linear or quadratic objective functions that have no direct interpretation in terms of dose-volume histogram (DVH) criteria, do not result in an optimum or have long solution times. We decrease the solution time of the existing linear and quadratic dose-based programming models (LP and QP, respectively) to allow optimizing over potential catheter positions using mixed integer programming. An additional average speed-up of 75% can be obtained by stopping the solver at an early stage, without deterioration of the plan quality. For a fixed catheter configuration, the dwell time optimization model LP solves to optimality in less than 15 s, which confirms earlier results. We propose an iterative procedure for QP that allows us to prescribe the target dose as an interval, while retaining independence between the solution time and the number of dose calculation points. This iterative procedure is comparable in speed to the LP model and produces better plans than the non-iterative QP. We formulate a new dose-volume-based model that maximizes V(100%) while satisfying pre-set DVH criteria. This model optimizes both catheter positions and dwell times within a few minutes depending on prostate volume and number of catheters, optimizes dwell times within 35 s and gives better DVH statistics than dose-based models. The solutions suggest that the correlation between the objective value and the clinical plan quality is weak in the existing dose-based models. PMID:23363622

  16. Brachytherapy or Conformal External Radiotherapy for Prostate Cancer: A Single-Institution Matched-Pair Analysis

    SciTech Connect

    Pickles, Tom; Keyes, Mira; Morris, W. James

    2010-01-15

    Purpose: In the absence of randomized study data, institutional case series have shown brachytherapy (BT) to produce excellent biochemical control (bNED) in patients with localized prostate cancer compared with alternative curative treatments. This study was designed to overcome some of the limitations of case series studies by using a matched-pair design in patients treated contemporaneously with BT and external beam radiation therapy (EBRT) at a single institution. Methods and Materials: Six hundred one eligible patients treated between 1998 and 2001 were prospectively followed up in our institutional databases and matched on a 1:1 basis for the following known prognostic variables: prostate-specific antigen (PSA) level, Gleason score, T stage, the use and duration of neoadjuvant androgen deprivation therapy, and the percentage of positive tissue core samples. Two hundred seventy-eight perfect matches of patients (139 in each group) with low- and intermediate-risk cancer were further analyzed. bNED (Phoenix definition) was the primary endpoint. Other endpoints were toxicity, PSA kinetics, and the secondary use of androgen deprivation therapy. Results: The 5-year bNED rates were 95% (BT) and 85% (EBRT) (p < 0.001). After 7 years, the BT bNED result was unchanged, but the rate in EBRT patients had fallen to 75%. The median posttreatment PSA nadirs were 0.04 ng/mL (BT) and 0.62 ng/mL (EBRT, p < 0.001), which predicted a higher ongoing treatment failure rate in association with EBRT use than with BT use. Late urinary toxicity and rectal/bowel toxicity were worse in patients treated with BT and EBRT, respectively. Conclusions: BT for both low-risk and selected intermediate-risk cancers achieves exceptional cure rates. Even with dose escalation, it will be difficult for EBRT to match the proven track record of BT seen over the past decade.

  17. BrachyView, A novel inbody imaging system for HDR prostate brachytherapy: Design and Monte Carlo feasibility study

    SciTech Connect

    Safavi-Naeini, M.; Han, Z.; Cutajar, D.; Guatelli, S.; Petasecca, M.; Lerch, M. L. F.; Franklin, D. R.; Jakubek, J.; Pospisil, S.; Bucci, J.; Zaider, M.; Rosenfeld, A. B.

    2013-07-15

    Purpose: High dose rate (HDR) brachytherapy is a form of radiation therapy for treating prostate cancer whereby a high activity radiation source is moved between predefined positions inside applicators inserted within the treatment volume. Accurate positioning of the source is essential in delivering the desired dose to the target area while avoiding radiation injury to the surrounding tissue. In this paper, HDR BrachyView, a novel inbody dosimetric imaging system for real time monitoring and verification of the radioactive seed position in HDR prostate brachytherapy treatment is introduced. The current prototype consists of a 15 Multiplication-Sign 60 mm{sup 2} silicon pixel detector with a multipinhole tungsten collimator placed 6.5 mm above the detector. Seven identical pinholes allow full imaging coverage of the entire treatment volume. The combined pinhole and pixel sensor arrangement is geometrically designed to be able to resolve the three-dimensional location of the source. The probe may be rotated to keep the whole prostate within the transverse plane. The purpose of this paper is to demonstrate the efficacy of the design through computer simulation, and to estimate the accuracy in resolving the source position (in detector plane and in 3D space) as part of the feasibility study for the BrachyView project.Methods: Monte Carlo simulations were performed using the GEANT4 radiation transport model, with a {sup 192}Ir source placed in different locations within a prostate phantom. A geometrically accurate model of the detector and collimator were constructed. Simulations were conducted with a single pinhole to evaluate the pinhole design and the signal to background ratio obtained. Second, a pair of adjacent pinholes were simulated to evaluate the error in calculated source location.Results: Simulation results show that accurate determination of the true source position is easily obtainable within the typical one second source dwell time. The maximum error in

  18. Three-dimensional seed reconstruction from an incomplete data set for prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Narayanan, Sreeram; Cho, Paul S.; Marks, Robert J., II

    2004-08-01

    Intra-operative dosimetry in prostate brachytherapy requires 3D coordinates of the implanted, radioactive seeds. Since CT is not readily available during the implant operation, projection x-rays are commonly used for intra-operative seed localization. Three x-ray projections are usually used. The requirement of the current seed reconstruction algorithms is that the seeds must be identified on all three projections. However, in practice this is often difficult to accomplish due to the problem of heavily clustered and overlapping seeds. We have developed an algorithm that permits seed reconstruction from an incomplete data set. Instead of all three projections, the new algorithm requires only one of the three projections to be complete. Furthermore, even if all three projections are incomplete, it can reconstruct 100% of the implanted seeds depending on how the undetected seeds are distributed among the projections. The method utilizes the principles of epipolar imaging geometry and pseudo-matching of the undetected seeds. The algorithm was successfully applied to a large number of clinical cases where seeds imperceptibly overlap in some projections.

  19. Three-dimensional seed reconstruction for prostate brachytherapy using Hough trajectories

    NASA Astrophysics Data System (ADS)

    Lam, Steve T.; Cho, Paul S.; Marks, Robert J., II; Narayanan, Sreeram

    2004-02-01

    In order to perform intra-operative or post-implant dosimetry in prostate brachytherapy, the 3D coordinates of the implanted radioactive seeds must be determined. Film or fluoroscopy based seed reconstruction techniques use back projection of x-ray data obtained at two or three x-ray positions. These methods, however, do not perform well when some of the seed images are undetected. To overcome this problem we have developed an alternate technique for 3D seed localization using the principle of Hough transform. The Hough method utilizes the fact that, for each seed coordinate in three dimensions, there exists a unique trajectory in Hough feature space. In this paper we present the Hough transform parametric equations to describe the path of the seed projections from one view to the next and a method to reconstruct the 3D seed coordinates. The results of simulation and phantom studies indicate that the Hough trajectory method can accurately determine the 3D seed positions even from an incomplete dataset.

  20. Characterization of ultrasound elevation beamwidth artifacts for prostate brachytherapy needle insertion

    SciTech Connect

    Peikari, Mohammad; Chen, Thomas Kuriran; Lasso, Anras; Heffter, Tamas; Fichtinger, Gabor; Burdette, Everette C.

    2012-01-15

    Purpose: Ultrasound elevation beamwidth leads to image artifacts and uncertainties in localizing objects (such as a surgical needle) in ultrasound images. The authors examined the clinical significance of errors caused by elevation beamwidth artifacts and imaging parameters in needle insertion procedures. Methods: Beveled prostate brachytherapy needles were inserted through all holes of a grid template under real-time transrectal ultrasound (TRUS) guidance. The needle tip position as indicated by the TRUS image was compared to their observed physical location. A new device was developed to measure the ultrasound elevation beamwidth. Results: Imaging parameters of the TRUS scanner have direct impact on the localization error ranging from 0.5 up to 4 mm. The smallest localization error was observed laterally close to the center of the grid template and axially within the beam's focal zone. Largest localization error occurs laterally around both sides of the grid template and axially within the beam's far field. The authors also found that the localization errors vary with both lateral and elevation offsets. Conclusions: The authors found properly adjusting the TRUS imaging settings to lower the ultrasound gain and power effectively minimized the appearance of elevation beamwidth artifacts and in turn reduced the localization errors of the needle tip.

  1. Topological methods for the comparison of structures using LDR-brachytherapy of the prostate as an example.

    PubMed

    Schiefer, H; von Toggenburg, F; Seelentag, W W; Plasswilm, L; Ries, G; Schmid, H-P; Leippold, T; Krusche, B; Roth, J; Engeler, D

    2009-08-21

    The dose coverage of low dose rate (LDR)-brachytherapy for localized prostate cancer is monitored 4-6 weeks after intervention by contouring the prostate on computed tomography and/or magnetic resonance imaging sets. Dose parameters for the prostate (V100, D90 and D80) provide information on the treatment quality. Those depend strongly on the delineation of the prostate contours. We therefore systematically investigated the contouring process for 21 patients with five examiners. The prostate structures were compared with one another using topological procedures based on Boolean algebra. The coincidence number C(V) measures the agreement between a set of structures. The mutual coincidence C(i, j) measures the agreement between two structures i and j, and the mean coincidence C(i) compares a selected structure i with the remaining structures in a set. All coincidence parameters have a value of 1 for complete coincidence of contouring and 0 for complete absence. The five patients with the lowest C(V) values were discussed, and rules for contouring the prostate have been formulated. The contouring and assessment were repeated after 3 months for the same five patients. All coincidence parameters have been improved after instruction. This shows objectively that training resulted in more consistent contouring across examiners. PMID:19641239

  2. The Impact of Brachytherapy on Prostate Cancer-Specific Mortality for Definitive Radiation Therapy of High-Grade Prostate Cancer: A Population-Based Analysis

    SciTech Connect

    Shen Xinglei; Keith, Scott W.; Mishra, Mark V.; Dicker, Adam P.; Showalter, Timothy N.

    2012-07-15

    Purpose: This population-based analysis compared prostate cancer-specific mortality (PCSM) in a cohort of patients with high-risk prostate cancer after nonsurgical treatment with external beam radiation therapy (EBRT), brachytherapy (BT), or combination (BT + EBRT). Methods and Materials: We identified from the Surveillance, Epidemiology and End Results database patients diagnosed from 1988 through 2002 with T1-T3N0M0 prostate adenocarcinoma of poorly differentiated grade and treated with BT, EBRT, or BT + EBRT. During this time frame, the database defined high grade as prostate cancers with Gleason score 8-10, or Gleason grade 4-5 if the score was not recorded. This corresponds to a cohort primarily with high-risk prostate cancer, although some cases where only Gleason grade was recorded may have included intermediate-risk cancer. We used multivariate models to examine patient and tumor characteristics associated with the likelihood of treatment with each radiation modality and the effect of radiation modality on PCSM. Results: There were 12,745 patients treated with EBRT (73.5%), BT (7.1%), or BT + EBRT (19.4%) included in the analysis. The median follow-up time for all patients was 6.4 years. The use of BT or BT + EBRT increased from 5.1% in 1988-1992 to 31.4% in 1998-2002. Significant predictors of use of BT or BT + EBRT were younger age, later year of diagnosis, urban residence, and earlier T-stage. On multivariate analysis, treatment with either BT (hazard ratio, 0.66; 95% confidence interval, 0.49-0.86) or BT + EBRT (hazard ratio, 0.77; 95% confidence ratio, 0.66-0.90) was associated with significant reduction in PCSM compared with EBRT alone. Conclusion: In patients with high-grade prostate cancer, treatment with brachytherapy is associated with reduced PCSM compared with EBRT alone. Our results suggest that brachytherapy should be investigated as a component of definitive treatment strategies for patients with high-risk prostate cancer.

  3. Second Primary Cancer After Radiotherapy for Prostate Cancer-A SEER Analysis of Brachytherapy Versus External Beam Radiotherapy

    SciTech Connect

    Abdel-Wahab, May Reis, Isildinha M.; Hamilton, Kara

    2008-09-01

    Purpose: To determine the incidence of second primary cancers (SPCs) and radiotherapy-induced SPCs (RTSPCs). Patients and Methods: The incidence of SPCs and RTSPCs was compared among four treatment groups with locoregional prostate adenocarcinoma in the 1973-2002 Surveillance, Epidemiology, and End Results database. These groups were no radiotherapy (RT), no surgery (Group 1); external beam RT (EBRT) (Group 2); brachytherapy (Group 3); and a combination of EBRT and brachytherapy (Group 4). Results: The age-adjusted estimates of SPCs were greater with EBRT than with brachytherapy (2,178 vs. 1,901 SPCs/100,000; p = 0.025) or with the no RT, no surgery group (1,971 SPCs/100,000; p <0.0001). The age-adjusted rate of late SPC ({>=}5 years) for EBRT (2,425 SPCs/100,000) was only significantly greater (p <0.0001) than that for no RT, no surgery (1,950 SPCs/100,000). The hazard ratio adjusted for age, race/ethnicity, and grade was constant at 1.263 for EBRT compared with no RT, no surgery (p <0.0001) but varied with the length of follow-up in both the brachytherapy (0.721 at 5 years to 1.200 at 9 years) and combination (0.920 at 5 years to 1.317 at 9 years) groups. The incidence of RTSPCs was only significantly different between the no RT, no surgery group and the EBRT group, with an increase of 162 cases/100,000 or a 0.16% increased SPC risk (p = 0.023). No significant differences in the incidence of RTSPC were seen between the RT groups. Conclusion: No significant differences were seen in the incidence of RTSPCs between the RT groups. The initial smaller relative risk of overall SPCs in the brachytherapy group increased with time until the curves converged, suggesting that the effect had resulted from patient selection bias.

  4. On the use of Kodak CR film for quality assurance of needle loading in I-125 seed prostate brachytherapy.

    PubMed

    Fog, L S; Nicholls, R; van Doom, T

    2007-09-01

    Low dose rate brachytherapy using implanted I-125 seeds as a monotherapy for prostate cancer is now in use in many hospitals. In contrast to fractionated brachytherapy treatments, where the effect of incorrect positioning of the source in one treatment fraction can be diminished by correcting the position in subsequent fractions, the I-125 seed implant is permanent, making correct positioning of the seeds in the prostate essential. The seeds are inserted into the prostate using needles. Correct configuration of seeds in the needles is essential in order to deliver the planned treatment. A comparison of an autoradiograph obtained by exposing film to the seed-loaded needles with the patient treatment plan is a valuable quality assurance tool. However, the time required to sufficiently expose Kodak XOMAT V film, currently used in this department is significant. This technical note presents the use of Kodak CR film for acquisition of the radiograph. The digital radiograph can be acquired significantly faster, has superior signal-to-noise ratio and contrast and has the usual benefits of digital film, e.g. a processing time which is shorter than that required for non-digital film, the possibility of image manipulation, possibility of paper printing and electronic storage.

  5. SU-E-T-279: Realization of Three-Dimensional Conformal Dose Planning in Prostate Brachytherapy

    SciTech Connect

    Li, Z; Jiang, S; Yang, Z; Bai, H; Zhang, X

    2014-06-01

    Purpose: Successful clinical treatment in prostate brachytherapy is largely dependent on the effectiveness of pre-surgery dose planning. Conventional dose planning method could hardly arrive at a satisfy result. In this abstract, a three-dimensional conformal localized dose planning method is put forward to ensure the accuracy and effectiveness of pre-implantation dose planning. Methods: Using Monte Carlo method, the pre-calculated 3-D dose map for single source is obtained. As for multiple seeds dose distribution, the maps are combined linearly to acquire the 3-D distribution. The 3-D dose distribution is exhibited in the form of isodose surface together with reconstructed 3-D organs group real-timely. Then it is possible to observe the dose exposure to target volume and normal tissues intuitively, thus achieving maximum dose irradiation to treatment target and minimum healthy tissues damage. In addition, the exfoliation display of different isodose surfaces can be realized applying multi-values contour extraction algorithm based on voxels. The needles could be displayed in the system by tracking the position of the implanted seeds in real time to conduct block research in optimizing insertion trajectory. Results: This study extends dose planning from two-dimensional to three-dimensional, realizing the three-dimensional conformal irradiation, which could eliminate the limitations of 2-D images and two-dimensional dose planning. A software platform is developed using VC++ and Visualization Toolkit (VTK) to perform dose planning. The 3-D model reconstruction time is within three seconds (on a Intel Core i5 PC). Block research could be conducted to avoid inaccurate insertion into sensitive organs or internal obstructions. Experiments on eight prostate cancer cases prove that this study could make the dose planning results more reasonable. Conclusion: The three-dimensional conformal dose planning method could improve the rationality of dose planning by safely reducing

  6. Reliability of EUCLIDIAN: An autonomous robotic system for image-guided prostate brachytherapy

    SciTech Connect

    Podder, Tarun K.; Buzurovic, Ivan; Huang Ke; Showalter, Timothy; Dicker, Adam P.; Yu, Yan

    2011-01-15

    Purpose: Recently, several robotic systems have been developed to perform accurate and consistent image-guided brachytherapy. Before introducing a new device into clinical operations, it is important to assess the reliability and mean time before failure (MTBF) of the system. In this article, the authors present the preclinical evaluation and analysis of the reliability and MTBF of an autonomous robotic system, which is developed for prostate seed implantation. Methods: The authors have considered three steps that are important in reliability growth analysis. These steps are: Identification and isolation of failures, classification of failures, and trend analysis. For any one-of-a-kind product, the reliability enhancement is accomplished through test-fix-test. The authors have used failure mode and effect analysis for collection and analysis of reliability data by identifying and categorizing the failure modes. Failures were classified according to severity. Failures that occurred during the operation of this robotic system were considered as nonhomogenous Poisson process. The failure occurrence trend was analyzed using Laplace test. For analyzing and predicting reliability growth, commonly used and widely accepted models, Duane's model and the Army Material Systems Analysis Activity, i.e., Crow's model, were applied. The MTBF was used as an important measure for assessing the system's reliability. Results: During preclinical testing, 3196 seeds (in 53 test cases) were deposited autonomously by the robot and 14 critical failures were encountered. The majority of the failures occurred during the first few cases. The distribution of failures followed Duane's postulation as well as Crow's postulation of reliability growth. The Laplace test index was -3.82 (<0), indicating a significant trend in failure data, and the failure intervals lengthened gradually. The continuous increase in the failure occurrence interval suggested a trend toward improved reliability. The MTBF

  7. Natural History of Clinically Staged Low- and Intermediate-Risk Prostate Cancer Treated With Monotherapeutic Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Wallner, Kent E.; Butler, Wayne M.

    2010-02-01

    Purpose: To evaluate the natural history of clinically staged low- and intermediate-risk prostate cancer treated with permanent interstitial seed implants as monotherapy. Methods and Materials: Between April 1995 and May 2005, 463 patients with clinically localized prostate cancer underwent brachytherapy as the sole definitive treatment. Men who received supplemental external beam radiotherapy or androgen deprivation therapy were excluded. Dosimetric implant quality was determined based on the minimum dose that covered 90% of the target volume and the volume of the prostate gland receiving 100% of the prescribed dose. Multiple parameters were evaluated as predictors of treatment outcomes. Results: The 12-year biochemical progression-free survival (bPFS), cause-specific survival, and overall survival rates for the entire cohort were 97.1%, 99.7%, and 75.4%, respectively. Only pretreatment prostate-specific antigen level, percent positive biopsy cores, and minimum dose that covered 90% of the target volume were significant predictors of biochemical recurrence. The bPFS, cause-specific survival, and overall survival rates were 97.4%, 99.6%, and 76.2%, respectively, for low-risk patients and 96.4%, 100%, and 74.0%, respectively, for intermediate-risk patients. The bPFS rate was 98.8% for low-risk patients with high-quality implants versus 92.1% for those with less adequate implants (p < 0.01), and it was 98.3% for intermediate-risk patients with high-quality implants versus 86.4% for those with less adequate implants (p < 0.01). Conclusions: High-quality brachytherapy implants as monotherapy can provide excellent outcomes for men with clinically staged low- and intermediate-risk prostate cancer. For these men, a high-quality implant can achieve results comparable to high-quality surgery in the most favorable pathologically staged patient subgroups.

  8. On the Need to Compensate for Edema-Induced Dose Reductions in Preplanned {sup 131}Cs Prostate Brachytherapy

    SciTech Connect

    Chen, Z. Jay Deng Jun; Roberts, Kenneth; Nath, Ravinder

    2008-01-01

    Purpose: Surgical trauma-induced edema and its protracted resolution can lead to significant dose reductions in preplanned {sup 131}Cs prostate brachytherapy. The purpose of this work was to examine whether these dose reductions should be actively compensated for and to estimate the magnitude of the additional irradiation needed for dose compensation. Methods and Materials: The quantitative edema resolution characteristics observed by Waterman et al. were used to examine the physical and radiobiologic effects of prostate edema in preplanned {sup 131}Cs implants. The need for dose compensation was assessed using the dose responses observed in {sup 125}I and {sup 103}Pd prostate implants. The biologically effective dose, calculated with full consideration of edema evolution, was used to estimate the additional irradiation needed for dose compensation. Results: We found that the edema-induced dose reduction in preplanned {sup 131}Cs implants could easily exceed 10% of the prescription dose for implants with moderate or large edema. These dose reductions could lead to a >10% reduction in the biochemical recurrence-free survival for individual patients if the effect of edema was ignored. For a prescribed dose of 120 Gy, the number of 2-Gy external beam fractions needed to compensate for a 5%, 10%, 15%, 20%, and 25% edema-induced dose reduction would be one, four, six, seven, and nine, respectively, for prostate cancer with a median potential doubling time of 42 days. The required additional irradiation increased for fast-growing tumors and/or those less efficient in sublethal damage repair. Conclusion: Compensation of edema-induced dose reductions in preplanned {sup 131}Cs prostate brachytherapy should be actively considered for those implants with moderate or large edema.

  9. Comparison of Real-Time Intraoperative Ultrasound-Based Dosimetry With Postoperative Computed Tomography-Based Dosimetry for Prostate Brachytherapy

    SciTech Connect

    Nag, Subir; Shi Peipei; Liu Bingren; Gupta, Nilendu; Bahnson, Robert R.; Wang, Jian Z.

    2008-01-01

    Purpose: To evaluate whether real-time intraoperative ultrasound (US)-based dosimetry can replace conventional postoperative computed tomography (CT)-based dosimetry in prostate brachytherapy. Methods and Materials: Between December 2001 and November 2002, 82 patients underwent {sup 103}Pd prostate brachytherapy. An interplant treatment planning system was used for real-time intraoperative transrectal US-guided treatment planning. The dose distribution was updated according to the estimated seed position to obtain the dose-volume histograms. Postoperative CT-based dosimetry was performed a few hours later using the Theraplan-Plus treatment planning system. The dosimetric parameters obtained from the two imaging modalities were compared. Results: The results of this study revealed correlations between the US- and CT-based dosimetry. However, large variations were found in the implant-quality parameters of the two modalities, including the doses covering 100%, 90%, and 80% of the prostate volume and prostate volumes covered by 100%, 150%, and 200% of the prescription dose. The mean relative difference was 38% and 16% for doses covering 100% and 90% of the prostate volume and 10% and 21% for prostate volumes covered by 100% and 150% of the prescription dose, respectively. The CT-based volume covered by 200% of the prescription dose was about 30% greater than the US-based one. Compared with CT-based dosimetry, US-based dosimetry significantly underestimated the dose to normal organs, especially for the rectum. The average US-based maximal dose and volume covered by 100% of the prescription dose for the rectum was 72 Gy and 0.01 cm{sup 3}, respectively, much lower than the 159 Gy and 0.65 cm{sup 3} obtained using CT-based dosimetry. Conclusion: Although dosimetry using intraoperative US-based planning provides preliminary real-time information, it does not accurately reflect the postoperative CT-based dosimetry. Until studies have determined whether US-based dosimetry

  10. High-Dose-Rate Brachytherapy as a Monotherapy for Favorable-Risk Prostate Cancer: A Phase II Trial

    SciTech Connect

    Barkati, Maroie; Williams, Scott G.; Foroudi, Farshad; Tai, Keen Hun; Chander, Sarat; Dyk, Sylvia van; See, Andrew; Duchesne, Gillian M.

    2012-04-01

    Purpose: There are multiple treatment options for favorable-risk prostate cancer. High-dose-rate (HDR) brachytherapy as a monotherapy is appealing, but its use is still investigational. A Phase II trial was undertaken to explore the value of such treatment in low-to-intermediate risk prostate cancer. Methods and Materials: This was a single-institution, prospective study. Eligible patients had low-risk prostate cancer features but also Gleason scores of 7 (51% of patients) and stage T2b to T2c cancer. Treatment with HDR brachytherapy with a single implant was administered over 2 days. One of four fractionation schedules was used in a dose escalation study design: 3 fractions of 10, 10.5, 11, or 11.5 Gy. Patients were assessed with the Common Terminology Criteria for Adverse Events version 2.0 for urinary toxicity, the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scoring schema for rectal toxicity, and the Expanded Prostate Cancer Index Composite (EPIC) questionnaire to measure patient-reported health-related quality of life. Biochemical failure was defined as a prostate-specific antigen (PSA) nadir plus 2 ng/ml. Results: Between 2003 and 2008, 79 patients were enrolled. With a median follow-up of 39.5 months, biochemical relapse occurred in 7 patients. Three- and 5-year actuarial biochemical control rates were 88.4% (95% confidence interval [CI], 78.0-96.2%) and 85.1% (95% CI, 72.5-94.5%), respectively. Acute grade 3 urinary toxicity was seen in only 1 patient. There was no instance of acute grade 3 rectal toxicity. Rates of late grade 3 rectal toxicity, dysuria, hematuria, urinary retention, and urinary incontinence were 0%, 10.3%, 1.3%, 9.0%, and 0%, respectively. No grade 4 or greater toxicity was recorded. Among the four (urinary, bowel, sexual, and hormonal) domains assessed with the EPIC questionnaire, only the sexual domain did not recover with time. Conclusions: HDR brachytherapy as a monotherapy for favorable

  11. SU-D-BRF-07: Ultrasound and Fluoroscopy Based Intraoperative Image-Guidance System for Dynamic Dosimetry in Prostate Brachytherapy

    SciTech Connect

    Kuo, N; Le, Y; Deguet, A; Prince, J; Song, D; Lee, J; Dehghan, E; Burdette, E; Fichtinger, G

    2014-06-01

    Purpose: Prostate brachytherapy is a common treatment method for low-risk prostate cancer patients. Intraoperative treatment planning is known to improve the treatment procedure and the outcome. The current limitation of intraoperative treatment planning is the inability to localize the seeds in relation to the prostate. We developed an image-guidance system to fulfill this need to achieve intraoperative dynamic dosimetry in prostate brachytherapy. Methods: Our system is based on standard imaging equipments available in the operating room, including the transrectal ultrasound (TRUS) and the mobile C-arm. A simple fiducial is added to compute the C-arm pose. Three fluoroscopic images and an ultrasound volume of the seeds and the prostate are acquired and processed by four image processing algorithms: seed segmentation, fiducial detection with pose estimation, seed reconstruction, and seeds-to-TRUS registration. The updated seed positions allow the physician to assess the quality of implantation and dynamically adjust the treatment plan during the course of surgery to achieve improved exit dosimetry. Results: The system was tested on 10 phantoms and 37 patients. Seed segmentation resulted in a 1% false negative and 2% false positive rates. Fiducial detection with pose estimation resulted in a detection rate of 98%. Seed reconstruction had a mean reconstruction error of 0.4 mm. Seeds-to-TRUS registration had a mean registration error of 1.3 mm. The total processing time from image acquisition to registration was approximately 1 minute. Conclusion: We present an image-guidance system for intraoperative dynamic dosimetry in prostate brachytherapy. Using standard imaging equipments and a simple fiducial, our system can be easily adopted in any clinics. Robust image processing algorithms enable accurate and fast computation of the delivered dose. Especially, the system enables detection of possible hot/cold spots during the surgery, allowing the physician to address these

  12. Brachytherapy Application With In Situ Dose Painting Administered by Gold Nanoparticle Eluters

    SciTech Connect

    Sinha, Neeharika; Cifter, Gizem; Sajo, Erno; Kumar, Rajiv; Sridhar, Srinivas; Nguyen, Paul L.; Cormack, Robert A.; Makrigiorgos, G. Mike; Ngwa, Wilfred

    2015-02-01

    Purpose: Recent studies show promise that administering gold nanoparticles (GNP) to tumor cells during brachytherapy could significantly enhance radiation damage to the tumor. A new strategy proposed for sustained administration of the GNP in prostate tumors is to load them into routinely used brachytherapy spacers for customizable in situ release after implantation. This in silico study investigated the intratumor biodistribution and corresponding dose enhancement over time due to GNP released from such GNP-loaded brachytherapy spacers (GBS). Method and Materials: An experimentally determined intratumoral diffusion coefficient (D) for 10-nm nanoparticles was used to estimate D for other sizes by using the Stokes-Einstein equation. GNP concentration profiles, obtained using D, were then used to calculate the corresponding dose enhancement factor (DEF) for each tumor voxel, using dose painting-by-numbers approach, for times relevant to the considered brachytherapy sources' lifetimes. The investigation was carried out as a function of GNP size for the clinically applicable low-dose-rate brachytherapy sources iodine-125 (I-125), palladium-103 (Pd-103), and cesium-131 (Cs-131). Results: Results showed that dose enhancement to tumor voxels and subvolumes during brachytherapy can be customized by varying the size of GNP released or eluted from the GBS. For example, using a concentration of 7 mg/g GNP, significant DEF (>20%) could be achieved 5 mm from a GBS after 5, 12, 25, 46, 72, 120, and 195 days, respectively, for GNP sizes of 2, 5, 10, 20, 30, and 50 nm and for 80 nm when treating with I-125. Conclusions: Analyses showed that using Cs-131 provides the highest dose enhancement to tumor voxels. However, given its relatively longer half-life, I-125 presents the most flexibility for customizing the dose enhancement as a function of GNP size. These findings provide a useful reference for further work toward development of potential new brachytherapy application with

  13. Prostate brachytherapy postimplant dosimetry: Seed orientation and the impact of dosimetric anisotropy in stranded implants

    SciTech Connect

    Chng, Nicholas; Spadinger, Ingrid; Rasoda, Rosey; Morris, W. James; Salcudean, Septimiu

    2012-02-15

    Purpose: In postimplant dosimetry for prostate brachytherapy, dose is commonly calculated using the TG-43 1D formalism, because seed orientations are difficult to determine from CT images, the current standard for the procedure. However, the orientation of stranded seeds soon after implantation is predictable, as these seeds tend to maintain their relative spacing, and orient themselves along the implant trajectory. The aim of this study was to develop a method for determining seed orientations from reconstructed strand trajectories, and to use this information to investigate the dosimetric impact of applying the TG-43 2D formalism to clinical postimplant analysis. Methods: Using in-house software, the preplan to postimplant seed correspondence was determined for a cohort of 30 patients during routine day-0 CT-based postimplant dosimetry. All patients were implanted with stranded-seed trains. Spline curves were fit to each set of seeds composing a strand, with the requirement that the distance along the spline between seeds be equal to the seed spacing within the strand. The orientations of the seeds were estimated by the tangents to the spline at each seed centroid. Dose distributions were then determined using the 1D and 2D TG-43 formalisms. These were compared using the TG-137 recommended dose metrics for the prostate, prostatic urethra, and rectum. Results: Seven hundred and sixty one strands were analyzed in total. Defining the z-axis to be cranial-positive and the x-axis to be left-lateral positive in the CT coordinate system, the average seed had an inclination of 21 deg. {+-} 10 deg. and an azimuth of -81 deg. {+-} 57 deg. These values correspond to the average strand rising anteriorly from apex to base, approximately parallel to the midsagittal plane. Clinically minor but statistically significant differences in dose metrics were noted. Compared to the 2D calculation, the 1D calculation underestimated prostate V100 by 1.1% and D90 by 2.3 Gy, while

  14. Investigating the dosimetric and tumor control consequences of prostate seed loss and migration

    SciTech Connect

    Knaup, Courtney; Mavroidis, Panayiotis; Esquivel, Carlos; Stathakis, Sotirios; Swanson, Gregory; Baltas, Dimos; Papanikolaou, Nikos

    2012-06-15

    Purpose: Low dose-rate brachytherapy is commonly used to treat prostate cancer. However, once implanted, the seeds are vulnerable to loss and movement. The goal of this work is to investigate the dosimetric and radiobiological effects of the types of seed loss and migration commonly seen in prostate brachytherapy. Methods: Five patients were used in this study. For each patient three treatment plans were created using Iodine-125, Palladium-103, and Cesium-131 seeds. The three seeds that were closest to the urethra were identified and modeled as the seeds lost through the urethra. The three seeds closest to the exterior of prostatic capsule were identified and modeled as those lost from the prostate periphery. The seed locations and organ contours were exported from Prowess and used by in-house software to perform the dosimetric and radiobiological evaluation. Seed loss was simulated by simultaneously removing 1, 2, or 3 seeds near the urethra 0, 2, or 4 days after the implant or removing seeds near the exterior of the prostate 14, 21, or 28 days after the implant. Results: Loss of one, two or three seeds through the urethra results in a D{sub 90} reduction of 2%, 5%, and 7% loss, respectively. Due to delayed loss of peripheral seeds, the dosimetric effects are less severe than for loss through the urethra. However, while the dose reduction is modest for multiple lost seeds, the reduction in tumor control probability was minimal. Conclusions: The goal of this work was to investigate the dosimetric and radiobiological effects of the types of seed loss and migration commonly seen in prostate brachytherapy. The results presented show that loss of multiple seeds can cause a substantial reduction of D{sub 90} coverage. However, for the patients in this study the dose reduction was not seen to reduce tumor control probability.

  15. 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

  16. Postoperative Nomogram Predicting the 9-Year Probability of Prostate Cancer Recurrence After Permanent Prostate Brachytherapy Using Radiation Dose as a Prognostic Variable

    SciTech Connect

    Potters, Louis; Roach, Mack; Davis, Brian J.; Stock, Richard G.; Ciezki, Jay P.; Zelefsky, Michael J.; Stone, Nelson N.; Fearn, Paul A.; Yu Changhong; Shinohara, Katsuto; Kattan, Michael W.

    2010-03-15

    Purpose: To report a multi-institutional outcomes study on permanent prostate brachytherapy (PPB) to 9 years that includes postimplant dosimetry, to develop a postimplant nomogram predicting biochemical freedom from recurrence. Methods and Materials: Cox regression analysis was used to model the clinical information for 5,931 patients who underwent PPB for clinically localized prostate cancer from six centers. The model was validated against the dataset using bootstrapping. Disease progression was determined using the Phoenix definition. The biological equivalent dose was calculated from the minimum dose to 90% of the prostate volume (D90) and external-beam radiotherapy dose using an alpha/beta of 2. Results: The 9-year biochemical freedom from recurrence probability for the modeling set was 77% (95% confidence interval, 73-81%). In the model, prostate-specific antigen, Gleason sum, isotope, external beam radiation, year of treatment, and D90 were associated with recurrence (each p < 0.05), whereas clinical stage was not. The concordance index of the model was 0.710. Conclusion: A predictive model for a postimplant nomogram for prostate cancer recurrence at 9-years after PPB has been developed and validated from a large multi-institutional database. This study also demonstrates the significance of implant dosimetry for predicting outcome. Unique to predictive models, these nomograms may be used a priori to calculate a D90 that likely achieves a desired outcome with further validation. Thus, a personalized dose prescription can potentially be calculated for each patient.

  17. Iodine-125 implant and external beam irradiation in patients with localized pancreatic carcinoma. [Efficacy and complications

    SciTech Connect

    Shipley, W.U.; Nardi, G.L.; Cohen, A.M.; Ling, C.C.

    1980-02-15

    Twelve patients with biopsy-proven clinically localized ductal pancreatic cancers (less than 7 cm in greatest diameter) judged unsuitable for resection were treated by bypass surgery, an Iodine-125 implant (20 to 39 mCi), and postoperative irradiation (4000 to 4500 rads). The potential problems of significant bleeding, pancreatic fistula, or pancreatitis were not experienced. A local recurrence developed in one patient and two recurred in regional lymph nodes. The projected median survival of the group is 11 months with four of the 12 patients still surviving. For purposes of comparison all patients with pancreatic ductal carcinoma treated by radical resection during a similar time were evaluated. All ten have died with a median survival of six months. Twelve of 22 (55%) of the combined implanted and resected groups have developed distant metastasis. Further pursuit of intraoperative techniques of irradiation in combination with adjuvant multidrug chemotherapy seems indicated in an attempt to prolong patient survival which is now limited by hematogenous metastases.

  18. Seed localization in ultrasound and registration to C-arm fluoroscopy using matched needle tracks for prostate brachytherapy.

    PubMed

    Moradi, Mehdi; Mahdavi, S Sara; Dehghan, Ehsan; Lobo, Julio R; Deshmukh, Sanchit; Morris, William James; Fichtinger, Gabor; Salcudean, Septimiu Tim E

    2012-09-01

    We propose a novel fiducial-free approach for the registration of C-arm fluoroscopy to 3-D ultrasound images of prostate brachytherapy implants to enable dosimetry. The approach involves the reliable detection of a subset of radioactive seeds from 3-D ultrasound, and the use of needle tracks in both ultrasound and fluoroscopy for registration. Seed detection in ultrasound is achieved through template matching in 3-D radio frequency ultrasound signals, followed by thresholding and spatial filtering. The resulting subset of seeds is registered to the complete reconstruction of the brachytherapy implant from multiple C-arm fluoroscopy views. To compensate for the deformation caused by the ultrasound probe, simulated warping is applied to the seed cloud from fluoroscopy. The magnitude of the applied warping is optimized within the registration process. The registration is performed in two stages. First, the needle track projections from fluoroscopy and ultrasound are matched. Only the seeds in the matched needles are then used as fiducials for point-based registration. We report results from a physical phantom with a realistic implant (average postregistration seed distance of 1.6 ± 1.2 mm) and from five clinical patient datasets (average error: 2.8 ± 1.5 mm over 128 detected seeds). We conclude that it is feasible to use RF ultrasound data, template matching, and spatial filtering to detect a reliable subset of brachytherapy seeds from ultrasound to enable registration to fluoroscopy for dosimetry.

  19. Calculated organ doses using Monte Carlo simulations in a reference male phantom undergoing HDR brachytherapy applied to localized prostate carcinoma

    SciTech Connect

    Candela-Juan, Cristian; Perez-Calatayud, Jose; Ballester, Facundo; Rivard, Mark J.

    2013-03-15

    Purpose: The aim of this study was to obtain equivalent doses in radiosensitive organs (aside from the bladder and rectum) when applying high-dose-rate (HDR) brachytherapy to a localized prostate carcinoma using {sup 60}Co or {sup 192}Ir sources. These data are compared with results in a water phantom and with expected values in an infinite water medium. A comparison with reported values from proton therapy and intensity-modulated radiation therapy (IMRT) is also provided. Methods: Monte Carlo simulations in Geant4 were performed using a voxelized phantom described in International Commission on Radiological Protection (ICRP) Publication 110, which reproduces masses and shapes from an adult reference man defined in ICRP Publication 89. Point sources of {sup 60}Co or {sup 192}Ir with photon energy spectra corresponding to those exiting their capsules were placed in the center of the prostate, and equivalent doses per clinical absorbed dose in this target organ were obtained in several radiosensitive organs. Values were corrected to account for clinical circumstances with the source located at various positions with differing dwell times throughout the prostate. This was repeated for a homogeneous water phantom. Results: For the nearest organs considered (bladder, rectum, testes, small intestine, and colon), equivalent doses given by {sup 60}Co source were smaller (8%-19%) than from {sup 192}Ir. However, as the distance increases, the more penetrating gamma rays produced by {sup 60}Co deliver higher organ equivalent doses. The overall result is that effective dose per clinical absorbed dose from a {sup 60}Co source (11.1 mSv/Gy) is lower than from a {sup 192}Ir source (13.2 mSv/Gy). On the other hand, equivalent doses were the same in the tissue and the homogeneous water phantom for those soft tissues closer to the prostate than about 30 cm. As the distance increased, the differences of photoelectric effect in water and soft tissue, and appearance of other materials

  20. Prospective evaluation of quality of life after interstitial brachytherapy for localized prostate cancer

    SciTech Connect

    Caffo, Orazio . E-mail: orazio.caffo@apss.tn.it; Fellin, Gianni; Bolner, Andrea; Coccarelli, Franco; Divan, Claudio; Frisinghelli, Michela; Mussari, Salvatore; Ziglio, Franco; Malossini, Gianni; Tomio, Luigi; Galligioni, Enzo

    2006-09-01

    Purpose: Permanent interstitial brachytherapy (IB) has become an increasingly appealing therapeutic option for localized prostate cancer (LPC) among physicians and patients because it involves short hospitalization and treatment and its postulated low degree of toxicity may reduce its impact on the patients' quality of life (QoL). The aim of this prospective study was to assess the impact of IB on the QoL of patients with LPC. Methods and Materials: A validated self-completed questionnaire was administered to the patients before and after IB and then at yearly intervals. The items allowed the identification of seven subscales exploring physical well-being (PHY), physical autonomy (POW), psychological well-being (PSY), relational life (REL), urinary function (URI), rectal function (REC), and sexual function (SEX). Results: The assessment of the QoL of 147 patients treated between May 2000 and February 2005 revealed no relevant differences in the PHY scale scores 1 month after IB or later, and the same was true of the POW, PSY, and REL scales. Urinary function significantly worsened after IB and returned to pretreatment levels only after 3 years; the impact of the treatment on the URI scale was greater in the patients with good baseline urinary function than in those presenting more urinary symptoms before IB. Rectal and sexual functions were significantly worse only at the post-IB evaluation. Conclusions: The results of the present study confirm that the impact of IB on the patients' QoL is low despite its transient negative effects on some function, and extend existing knowledge concerning QoL after IB.

  1. Fast radioactive seed localization in intraoperative cone beam CT for low-dose-rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Hu, Yu-chi; Xiong, Jian-ping; Cohan, Gilad; Zaider, Marco; Mageras, Gig; Zelefsky, Michael

    2013-03-01

    A fast knowledge-based radioactive seed localization method for brachytherapy was developed to automatically localize radioactive seeds in an intraoperative volumetric cone beam CT (CBCT) so that corrections, if needed, can be made during prostate implant surgery. A transrectal ultrasound (TRUS) scan is acquired for intraoperative treatment planning. Planned seed positions are transferred to intraoperative CBCT following TRUS-to-CBCT registration using a reference CBCT scan of the TRUS probe as a template, in which the probe and its external fiducial markers are pre-segmented and their positions in TRUS are known. The transferred planned seeds and probe serve as an atlas to reduce the search space in CBCT. Candidate seed voxels are identified based on image intensity. Regions are grown from candidate voxels and overlay regions are merged. Region volume and intensity variance is checked against known seed volume and intensity profile. Regions meeting the above criteria are flagged as detected seeds; otherwise they are flagged as likely seeds and sorted by a score that is based on volume, intensity profile and distance to the closest planned seed. A graphical interface allows users to review and accept or reject likely seeds. Likely seeds with approximately twice the seed volume are automatically split. Five clinical cases are tested. Without any manual correction in seed detection, the method performed the localization in 5 seconds (excluding registration time) for a CBCT scan with 512×512×192 voxels. The average precision rate per case is 99% and the recall rate is 96% for a total of 416 seeds. All false negative seeds are found with 15 in likely seeds and 1 included in a detected seed. With the new method, updating of calculations of dose distribution during the procedure is possible and thus facilitating evaluation and improvement of treatment quality.

  2. Comparison of Oncentra® Brachy IPSA and graphical optimisation techniques: a case study of HDR brachytherapy head and neck and prostate plans

    SciTech Connect

    Jameson, Michael G; Ohanessian, Lucy; Batumalai, Vikneswary; Patel, Virendra; Holloway, Lois C

    2015-06-15

    There are a number of different dwell positions and time optimisation options available in the Oncentra® Brachy (Elekta Brachytherapy Solutions, Veenendaal, The Netherlands) brachytherapy treatment planning system. The purpose of this case study was to compare graphical (GRO) and inverse planning by simulated annealing (IPSA) optimisation techniques for interstitial head and neck (HN) and prostate plans considering dosimetry, modelled radiobiology outcome and planning time. Four retrospective brachytherapy patients were chosen for this study, two recurrent HN and two prostatic boosts. Manual GRO and IPSA plans were generated for each patient. Plans were compared using dose–volume histograms (DVH) and dose coverage metrics including; conformity index (CI), homogeneity index (HI) and conformity number (CN). Logit and relative seriality models were used to calculate tumour control probability (TCP) and normal tissue complication probability (NTCP). Approximate planning time was also recorded. There was no significant difference between GRO and IPSA in terms of dose metrics with mean CI of 1.30 and 1.57 (P > 0.05) respectively. IPSA achieved an average HN TCP of 0.32 versus 0.12 for GRO while for prostate there was no significant difference. Mean GRO planning times were greater than 75 min while average IPSA planning times were less than 10 min. Planning times for IPSA were greatly reduced compared to GRO and plans were dosimetrically similar. For this reason, IPSA makes for a useful planning tool in HN and prostate brachytherapy.

  3. Incidence of seed migration to the chest, abdomen, and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds

    PubMed Central

    2011-01-01

    Background The aim was to determine the incidence of seed migration not only to the chest, but also to the abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds. Methods We reviewed the records of 267 patients who underwent prostate brachytherapy with loose 125I seeds. After seed implantation, orthogonal chest radiographs, an abdominal radiograph, and a pelvic radiograph were undertaken routinely to document the occurrence and sites of seed migration. The incidence of seed migration to the chest, abdomen, and pelvis was calculated. All patients who had seed migration to the abdomen and pelvis subsequently underwent a computed tomography scan to identify the exact location of the migrated seeds. Postimplant dosimetric analysis was undertaken, and dosimetric results were compared between patients with and without seed migration. Results A total of 19,236 seeds were implanted in 267 patients. Overall, 91 of 19,236 (0.47%) seeds migrated in 66 of 267 (24.7%) patients. Sixty-nine (0.36%) seeds migrated to the chest in 54 (20.2%) patients. Seven (0.036%) seeds migrated to the abdomen in six (2.2%) patients. Fifteen (0.078%) seeds migrated to the pelvis in 15 (5.6%) patients. Seed migration occurred predominantly within two weeks after seed implantation. None of the 66 patients had symptoms related to the migrated seeds. Postimplant prostate D90 was not significantly different between patients with and without seed migration. Conclusion We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90. PMID:21974959

  4. Radiation Dose Predicts for Biochemical Control in Intermediate-Risk Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy

    SciTech Connect

    Ho, Alice Y.; Burri, Ryan J.; Cesaretti, Jamie A.; Stone, Nelson N.; Stock, Richard G.

    2009-09-01

    Purpose: To evaluate the influence of patient- and treatment-related factors on freedom from biochemical failure (FFbF) in patients with intermediate-risk prostate cancer. Methods and Materials: From a prospectively collected database of 2250 men treated at Mount Sinai Hospital from 1990 to 2004 with low-dose-rate brachytherapy for prostate cancer, 558 men with either one or more intermediate-risk features (prostate-specific antigen [PSA] level 10-20 ng/mL, Gleason score 7, or Stage T2b) were identified who had a minimum follow-up of 24 months and postimplant CT-based dosimetric analysis. Biologically effective dose (BED) values were calculated to compare doses from different isotopes and treatment regimens. Patients were treated with brachytherapy with or without hormone therapy and/or external-beam radiotherapy. Patient- and treatment-related factors were analyzed with respect to FFbF. The median follow-up was 60 months (range, 24-167 months). Biochemical failure was defined according to the Phoenix definition. Univariate analyses were used to determine whether any variable was predictive of FFbF. A two-sided p value of <0.05 was considered significant. Results: Overall, the actuarial FFbF at 10 years was 86%. Dose (BED <150 Gy{sub 2} vs. {>=}150 Gy{sub 2}) was the only significant predictor of FFbF (p < 0.001). None of the other variables (PSA, external-beam radiotherapy, Gleason score, treatment type, hormones, stage, and number of risk factors) was found to be a statistically significant predictor of 10-year FFbF. Conclusions: Radiation dose is an important predictor of FFbF in intermediate-risk prostate cancer. Treatment should continue to be individualized according to presenting disease characteristics until results from Radiation Therapy Oncology Group trial 0232 become available.

  5. Urinary Symptom Flare in 712 {sup 125}I Prostate Brachytherapy Patients: Long-Term Follow-Up

    SciTech Connect

    Keyes, Mira; Miller, Stacy; Moravan, Veronika; Pickles, Tom; Liu, Mitchell; Spadinger, Ingrid; Lapointe, Vincent; Morris, W. James

    2009-11-01

    Purpose: To describe the late transient worsening of urinary symptoms ('urinary symptom flare') in 712 consecutive prostate brachytherapy patients, associated predictive factors, association with rectal and urinary toxicity, and the development of erectile dysfunction. Methods and Materials: Patients underwent implantation between 1998 and 2003 (median follow-up, 57 months). International Prostate Symptom Score (IPSS), Radiation Therapy Oncology Group (RTOG) toxicity, and erectile function data were prospectively collected. Flare was defined as an increase in IPSS of >=5 and of >=8 points greater than the post-treatment nadir. The relationships between the occurrence of flare and the patient, tumor, and treatment characteristics were examined. The Cox proportional hazards method was used to test individual variables and the multivariate models. Results: The incidence of flare was 52% and 30% using the flare definition of an IPSS of >=5 and >=8 points greater than the postimplant nadir, respectively. Of the patients with symptoms, 65% had resolution of their symptoms within 6 months and 91% within 1 year. Flares most commonly occurred 16-24 months after implantation. On multivariate analysis, a greater baseline IPSS and greater maximal postimplant IPSS were the predictors of flare, regardless of the flare definition used. Androgen suppression was a predictor for fewer flares (IPSS >=5). Diabetes and prostate edema predicted for more frequent flares (IPSS >=8). Patients with flare had a greater incidence of RTOG Grade 3 urinary toxicity and RTOG Grade 2 or greater rectal toxicity. No association was found between erectile dysfunction and the occurrence of flare. Conclusion: Urinary symptom flare is a common, transient phenomenon after prostate brachytherapy. A greater baseline IPSS and maximal postimplant IPSS were the strongest predictive factors. Flare was associated with a greater incidence of late RTOG Grade 3 urinary toxicity and greater rate of late RTOG Grade

  6. HDR brachytherapy of prostate cancer – two years experience in Greater Poland Cancer Centre

    PubMed Central

    Skowronek, Janusz; Chicheł, Adam

    2009-01-01

    Purpose The aim of this work was to analyze the results and complications of three treatment schemes of patients with initially localized prostate cancer after two years of observation time. Material and methods Sixty-three patients were enrolled into the study and divided into groups according to radiation schemes (I group – EBRT 50 Gy/BRT 15 Gy, II – EBRT 46 Gy/BRT 2 × 10 Gy, III group – BRT 3 × 15 Gy). Group I, II and III consisted of 46 (73%), 14 (22.2%), 3 (4.8%) patients, respectively. The low-, intermediate- and high risk groups consisted of 23 (36.5%), 18 (28.5%) and 22 (35%) men, respectively. Results and tolerance of the treatment and acute complications in analyzed groups were discussed. Results Median observation time was 24 months. Complete remission was observed in 43 patients (68.3%) out of the whole group. Locoregional and distal metastases progression were noted in 4 patients (6.4%). Partial remission was observed in low-, intermediate- and high risk group: 7.9%, 9.5% and 9.5% of all men. Nadir of PSA results were estimated as mean value of 0.094 ng/ml, average 0.0-0.63. The mean value for the complete group decreased from 0.98 ng/ml (range 0.0-9.7) in the third months to 0.32 ng/ml after one year (0.0-3.34) of the end of treatment time. Urologic and gastrointenstinal side effects were noted in different rates according to 1 month observation (dysuria – 22.2%, urinary incontinence – 7.9%, frequency – 58.7%, weak stream – 68.3%, rectal bleeding – 15.9%). Conclusions 1. HDR brachytherapy of prostate cancer can be used as a boost after or before the external beam radiation therapy in different treatment schemes. 2. In selected groups under investigation trials, sole HDR-BRT is a suitable method of treatment. 3. To confirm superiority of analyzed modality treatment a prospective investigation with larger groups of patients would be required.

  7. A study of a pretreatment method to predict the number of I-125 seeds required for prostate brachytherapy

    SciTech Connect

    Al-Qaisieh, Bashar . E-mail: bashar@medphysics.leeds.ac.uk; Brearley, Elizabeth; St Clair, Shaun; Flynn, Anthony

    2006-05-01

    Purpose: Prediction of the number of iodine seeds (I-125) required for prostate implantation is an important tool to reduce the number of unused seeds for brachytherapy. This study was designed to investigate the relationship between the number of seeds implanted vs. prostate volume. This can produce a tool to accurately estimate the number of seeds required for a given target volume. In addition, total cost of treatment, personal radiation risks during storage and handling, and errors in accounting for seeds can be reduced. Methods and Materials: Data from two groups of patients who had I-125 seed prostate implants (Oncura/Amersham RAPIDStrand model 6711 I-125) have been separately analyzed: (A) The relationship between prostate volume vs. number of seeds implanted was based on 401 patients treated between 1999 and 2002 who were implanted with seeds of air kerma strength (AKS) of 0.459 {mu}Gyh{sup -1} at 1 m per seed. (B) The relationship between prostate volume vs. total seed AKS was analyzed. This was based on 628 patients treated between 1999 and 2002 who were implanted with a range of seed strengths from 0.381 to 0.521 U. Both patient groups were subdivided into integer prostate volume bins. For each bin, the mean and 95% confidence intervals (CI) for the implanted number of seeds or total AKS implanted were calculated. The upper 95% CI was used to investigate the relationship between the number of seeds implanted and total AKS implanted vs. prostate volume. Results: The new method of predicting the number of seeds shows valid and accurate results. The required number of seeds can be predicted, which helps to reduce the number of leftover seeds to 3% of the total number of seeds ordered. Conclusion: The number of I-125 seeds or the total activity that is required to deliver the prescribed dose for the target volume can be predicted. This could reduce the overall treatment cost by accurate seed ordering before implantation.

  8. Predictors of Prostate Cancer-Specific Mortality in Elderly Men With Intermediate-Risk Prostate Cancer Treated With Brachytherapy With or Without External Beam Radiation Therapy

    SciTech Connect

    Nanda, Akash; Moran, Brian J.; Braccioforte, Michelle H.; Dosoretz, Daniel; Salenius, Sharon; Katin, Michael; Ross, Rudi; D'Amico, Anthony V.

    2010-05-01

    Purpose: To identify clinical factors associated with prostate cancer-specific mortality (PCSM), adjusting for comorbidity, in elderly men with intermediate-risk prostate cancer treated with brachytherapy alone or in conjunction with external beam radiation therapy. Methods and Materials: The study cohort comprised 1,978 men of median age 71 (interquartile range, 66-75) years with intermediate-risk disease (Gleason score 7, prostate-specific antigen (PSA) 20 ng/mL or less, tumor category T2c or less). Fine and Gray's multivariable competing risks regression was used to assess whether prevalent cardiovascular disease (CVD), age, treatment, year of brachytherapy, PSA level, or tumor category was associated with the risk of PCSM. Results: After a median follow-up of 3.2 (interquartile range, 1.7-5.4) years, the presence of CVD was significantly associated with a decreased risk of PCSM (adjusted hazard ratio, 0.20; 95% CI 0.04-0.99; p = 0.05), whereas an increasing PSA level was significantly associated with an increased risk of PCSM (adjusted hazard ratio 1.14; 95% CI 1.02-1.27; p = 0.02). In the absence of CVD, cumulative incidence estimates of PCSM were higher (p = 0.03) in men with PSA levels above as compared with the median PSA level (7.3 ng/mL) or less; however, in the setting of CVD there was no difference (p = 0.27) in these estimates stratified by the median PSA level (6.9 ng/mL). Conclusions: In elderly men with intermediate-risk prostate cancer, CVD status is a negative predictor of PCSM and affects the prognostic capacity of pretreatment PSA level. These observations support the potential utility of prerandomization stratification by comorbidity to more accurately assess prognostic factors and treatment effects within this population.

  9. Method for the simultaneous preparation of Radon-211, Xenon-125, Xenon-123, Astatine-211, Iodine-125 and Iodine-123

    DOEpatents

    Mirzadeh, Saed; Lambrecht, Richard M.

    1987-01-01

    A method for simultaneously preparing Radon-211, Astatine-211, Xenon-125, Xenon-123, Iodine-125 and Iodine-123 in a process that includes irradiating a fertile metal material then using a one-step chemical procedure to collect a first mixture of about equal amounts of Radon-211 and Xenon-125, and a separate second mixture of about equal amounts of Iodine-123 and Astatine-211.

  10. SU-F-19A-08: Optimal Time Release Schedule of In-Situ Drug Release During Permanent Prostate Brachytherapy

    SciTech Connect

    Cormack, R; Ngwa, W; Makrigiorgos, G; Tangutoori, S; Rajiv, K; Sridhar, S

    2014-06-15

    Purpose: Permanent prostate brachytherapy spacers can be used to deliver sustained doses of radiosentitizing drug directly to the target, in order to enhance the radiation effect. Implantable nanoplatforms for chemo-radiation therapy (INCeRTs) have a maximum drug capacity and can be engineered to control the drug release schedule. The optimal schedule for sensitization during continuous low dose rate irradiation is unknown. This work studies the optimal release schedule of drug for both traditional sensitizers, and those that work by suppressing DNA repair processes. Methods: Six brachytherapy treatment plans were used to model the anatomy, implant geometry and calculate the spatial distribution of radiation dose and drug concentrations for a range of drug diffusion parameters. Three state partial differential equations (cells healthy, damaged or dead) modeled the effect of continuous radiation (radiosensitivities α,β) and cellular repair (time tr) on a cell population. Radiosensitization was modeled as concentration dependent change in α,β or tr which with variable duration under the constraint of fixed total drug release. Average cell kill was used to measure effectiveness. Sensitization by means of both enhanced damage and reduced repair were studied. Results: Optimal release duration is dependent on the concentration of radiosensitizer compared to the saturation concentration (csat) above which additional sensitization does not occur. Long duration drug release when enhancing α or β maximizes cell death when drug concentrations are generally over csat. Short term release is optimal for concentrations below saturation. Sensitization by suppressing repair has a similar though less distinct trend that is more affected by the radiation dose distribution. Conclusion: Models of sustained local radiosensitization show potential to increase the effectiveness of radiation in permanent prostate brachytherapy. INCeRTs with high drug capacity produce the greatest

  11. A Small Tolerance for Catheter Displacement in High-Dose Rate Prostate Brachytherapy is Necessary and Feasible

    SciTech Connect

    Tiong, Albert; Bydder, Sean; Ebert, Martin; Caswell, Nikki; Waterhouse, David; Spry, Nigel; Camille, Peter; Joseph, David

    2010-03-15

    Purpose: We examined catheter displacement in patients treated with fractionated high-dose rate (HDR) brachytherapy boost for prostate cancer and the impact this had on tumor control probability (TCP). These data were used to make conclusions on an acceptable amount of displacement. Methods and Materials: The last 20 patients treated with HDR brachytherapy boost for prostate cancer at our center in 2007 were replanned using simulated interstitial catheter displacements of 3, 6, 9, and 12 mm with originally planned dwell times. The computer-modeled dose-volume histograms for the clinical target volumes were exported and used to calculate the TCP of plans with displaced needles relative to the original plan. Actual catheter displacements were also measured before and after manual adjustment in all patients treated in 2007. Results: In the 20 patients who were replanned for caudal catheter displacements of 3, 6, 9, and 12 mm, the median relative TCP was 0.998, 0.964, 0.797, and 0.265, respectively (p < 0.01 when all medians were compared). All patients replanned with a 3-mm displacement, compared with only 75% with a 6-mm displacement, had a relative TCP greater than 0.950. In the 91 patients treated in 2007, before adjustment, 82.3% of fractions had a displacement greater than 3 mm compared with 12.2% of fractions after adjustment. Conclusions: Catheter displacement in HDR brachytherapy significantly compromises the TCP. The tolerance for these movements should be small (<=3 mm). Correcting these displacements to within acceptable limits is feasible.

  12. Brain necrosis after permanent low-activity iodine-125 implants: case report and review of toxicity from focal radiation.

    PubMed

    Bampoe, J; Nag, S; Leung, P; Laperriere, N; Bernstein, M

    2000-01-01

    Focal irradiation has emerged as a useful modality in the management of malignant brain tumors. Its main limitation is radiation necrosis. We report on the radiation dose distribution in the cerebellum of a patient who developed imaging and autopsy diagnosis of radiation necrosis after permanent iodine-125 implants for a solitary osseous plasmacytoma of her left occipital condyle. A 55-year-old woman initially presented with neck and occipital pain and a lytic lesion of her left occipital condyle. A cytological diagnosis of solitary osseous plasmacytoma was made by transpharyngeal needle biopsy. After an initial course of external beam radiation, the patient required further treatment with systemic chemotherapy 21 months later for clinical and radiographic progression of her disease. She ultimately required subtotal surgical resection of an anaplastic plasmacytoma with intracranial extension. Permanent low-activity iodine-125 seeds were implanted in the tumor cavity. Satisfactory local control was achieved. However, clinical and imaging signs of radiation damage appeared 28 months after iodine-125 seed implantation. Progressive systemic myeloma led to her death 11 years after presentation and 9 years after seed implantation. Radiation dose distribution is described, with a discussion of toxicity from focal radiation dose escalation.

  13. Comparison of Dosimetric and Biologic Effective Dose Parameters for Prostate and Urethra Using {sup 131}Cs and {sup 125}I for Prostate Permanent Implant Brachytherapy

    SciTech Connect

    Sahgal, Arjun; Jabbari, Siavash; Chen, Josephine; Pickett, Barbie; Roach, Mack; Weinberg, Vivian; Hsu, I-C.; Pouliot, Jean

    2008-09-01

    Purpose: To compare the urethral and prostate absolute and biologic effective doses (BEDs) for {sup 131}Cs and {sup 125}I prostate permanent implant brachytherapy (PPI). Methods and Materials: Eight previously implanted manually planned {sup 125}I PPI patients were replanned manually with {sup 131}Cs, and re-planned using Inverse Planning Simulated Annealing. {sup 131}Cs activity and the prescribed dose (115 Gy) were determined from that recommended by IsoRay. The BED was calculated for the prostate and urethra using an {alpha}/{beta} ratio of 2 and was also calculated for the prostate using an {alpha}/{beta} ratio of 6 and a urethral {alpha}/{beta} ratio of 2. The primary endpoints of this study were the prostate D{sub 90} BED (pD{sub 90}BED) and urethral D{sub 30} BED normalized to the maximal potential prostate D{sub 90} BED (nuD{sub 30}BED). Results: The manual plan comparison ({alpha}/{beta} = 2) yielded no significant difference in the prostate D{sub 90} BED (median, 192 Gy{sub 2} for both isotopes). No significant difference was observed for the nuD{sub 30}BED (median, 199 Gy{sub 2} and 202 Gy{sub 2} for {sup 125}I and {sup 131}Cs, respectively). For the inverse planning simulated annealing plan comparisons ({alpha}/{beta} 2), the prostate D{sub 90} BED was significantly lower with {sup 131}Cs than with {sup 125}I (median, 177 Gy{sub 2} vs. 187 Gy{sub 2}, respectively; p = 0.01). However, the nuD{sub 30}BED was significantly greater with {sup 131}Cs than with {sup 125}I (median, 192 Gy{sub 2} vs. 189 Gy{sub 2}, respectively; p = 0.01). Both the manual and the inverse planning simulated annealing plans resulted in a significantly lower prostate D{sub 90} BED (p = 0.01) and significantly greater nuD{sub 30}BED for {sup 131}Cs (p = 0.01), compared with {sup 125}I, when the prostate {alpha}/{beta} ratio was 6 and the urethral {alpha}/{beta} ratio was 2. Conclusion: This report highlights the controversy in comparing the dose to both the prostate and the organs

  14. Development of Late Toxicity and International Prostate Symptom Score Resolution After External-Beam Radiotherapy Combined With Pulsed Dose Rate Brachytherapy for Prostate Cancer

    SciTech Connect

    Pieters, Bradley R.; Rezaie, Elisa; Geijsen, Elisabeth D.; Koedooder, Kees; Grient, Johan N.B. van der; Blank, Leo E.C.M.; Reijke, Theo M. de; Koning, Caro C.E.

    2011-11-01

    Purpose: To investigate the development of gastrointestinal (GI) toxicity, genitourinary (GU) toxicity, erectile dysfunction, and International Prostate Symptom Score (IPSS) resolution in a cohort of patients treated with external-beam radiotherapy (EBRT) followed by a brachytherapy pulsed dose rate (PDR) boost. Methods and Materials: Between 2002 and 2008, 110 patients were treated with 46-Gy EBRT followed by PDR brachytherapy (24.96-28.80 Gy). The investigated outcome variables, GI toxicity, GU toxicity, erectile dysfunction, and IPSS were prospectively scored at several time points during follow-up. Association between time (as continuous and categorical variable) and the outcome variables was assessed using generalized linear models. Results: No statistically significant association was found between time (continuous) and GI toxicity (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.89-1.06), GU toxicity (OR, 0.97; 95% CI, 0.91-1.03), erectile dysfunction (OR, 1.06; 95% CI, 0.99-1.11), and IPSS (-0.11; 95% CI, -0.41-0.20). Also, no statistically significant association was found between these variables and time as a categorical variable. GU toxicity was associated with IPSS resolution (OR, 1.16; 95% CI, 1.09-1.24). Posttreatment IPSS was associated with pretreatment IPSS (0.52; 95% CI, 0.25-0.79). Conclusions: No accumulation of high-grade toxicity over time could be established for a group of patients treated with EBRT and PDR brachytherapy for prostate cancer, probably because high-grade late toxicity resolves with time. Also, differences in IPSS values among patients are smaller after treatment than before treatment.

  15. Comparison of implant quality between intraoperatively built custom-linked seeds and loose seeds in permanent prostate brachytherapy using sector analysis

    PubMed Central

    Katayama, Norihisa; Takemoto, Mitsuhiro; Takamoto, Atsushi; Ihara, Hiroki; Katsui, Kuniaki; Ebara, Shin; Nasu, Yasutomo; Kanazawa, Susumu

    2016-01-01

    We compared the implant quality of intraoperatively built custom-linked (IBCL) seeds with loose seeds in permanent prostate brachytherapy. Between June 2012 and January 2015, 64 consecutive prostate cancer patients underwent brachytherapy with IBCL seeds (n = 32) or loose seeds (n = 32). All the patients were treated with 144 Gy of brachytherapy alone. Brachytherapy was performed using a dynamic dose calculation technique. Computed tomography/magnetic resonance imaging fusion-based dosimetry was performed 1 month after brachytherapy. Post-implant dose–volume histogram (DVH) parameters, prostate sector dosimetry, operation time, seed migration, and toxicities were compared between the IBCL seed group and the loose seed group. A sector analysis tool was used to divide the prostate into six sectors (anterior and posterior sectors at the base, mid-gland, and apex). V100 (95.3% vs 89.7%; P = 0.014) and D90 (169.7 Gy vs 152.6 Gy; P = 0.013) in the anterior base sector were significantly higher in the IBCL seed group than in the loose seed group. The seed migration rate was significantly lower in the IBCL seed group than in the loose seed group (6% vs 66%; P < 0.001). Operation time per seed was significantly longer in the IBCL seed group than in the loose seed group (1.31 min vs 1.13 min; P = 0.003). Other post-implant DVH parameters and toxicities did not differ significantly between the two groups. Our study showed more dose coverage post-operatively in the anterior base prostate sector and less seed migration in IBCL seed implantation compared with loose seed implantation. PMID:26976125

  16. Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

    PubMed Central

    Lu, Zheng; Dong, Teng-Hui; Si, Pei-Ren; Shen, Wei; Bi, Yi-Liang; Min, Min; Chen, Xin; Liu, Yan

    2016-01-01

    Background: Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (125I) seed implantation. Methods: The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of 125I seeds CLDR irradiation. The orthotopic models of PNI were established, and 125I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after 125I seed implantation. Results: The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months. Conclusions: The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain. PMID:27748339

  17. Iodine-125-labeled cRGD-gold nanoparticles as tumor-targeted radiosensitizer and imaging agent

    NASA Astrophysics Data System (ADS)

    Su, Ning; Dang, Yajie; Liang, Guangli; Liu, Guizhi

    2015-04-01

    Research interests on radiosensitive property of gold nanoparticles (GNPs) are rapidly raised because of the extensively proved in vitro effectiveness and clinical necessity. However, the issue of targeted accumulation of GNPs in tumor tissues hindered the transference to in vivo applications. In this study, hybrid nano-sized cyclic Arg-Gly-Asp-conjugated GNPs (cRGD-GNPs) integrated with radioactive iodine-125 was fabricated as tumor-targeted radiosensitizer. Therapeutic effects, including acute apoptosis (2 days post treatment) and long-term influence (up to 21 days), were investigated on NCI-H446 tumor-bearing mice via Tc-99 m-Annexin V SPECT and volume measurements, respectively. Apoptosis and volume loss were consistent in showing that tumor growth was effectively suppressed via the treatment of 125I-cRGD-GNP sensitized radiotherapy (RT), a more significantly radiosensitive effect than the treatment of non-targeted GNPs with RT, RT treatment alone, and no treatment. SPECT/CT images showed that the uptake of cRGD-GNPs by tumor tissues reached the peak target/non-target value of 4.76 at around 2 h post injection, and dynamic radioactivity monitoring showed that 125I-cRGD-GNPs maintained about 2.5% of injected dosage at 55 h post injection. For long-term influence, a significant radiosensitized RT-induced volume loss was observed. Hence, cyclic RGD conjugation makes the GNP-based radiosensitizer tumor targeting, offering a new modality for enhancing radiotherapeutic efficacy. Additionally, the introduction of I-125 serves as both a therapeutic factor and a radiotracer for in vivo tracking of GNPs.

  18. Prostate-specific antigen nadir after high-dose-rate brachytherapy predicts long-term survival outcomes in high-risk prostate cancer

    PubMed Central

    Satoh, Takefumi; Ishiyama, Hiromichi; Tabata, Ken-ichi; Komori, Shouko; Sekiguchi, Akane; Ikeda, Masaomi; Kurosaka, Shinji; Fujita, Tetsuo; Kitano, Masashi; Hayakawa, Kazushige; Iwamura, Masatsugu

    2016-01-01

    Purpose To evaluate the prognostic value of prostate-specific antigen nadir (nPSA) after high-dose-rate (HDR) brachytherapy in clinically non-metastatic high-risk prostate cancer patients. Material and methods Data from 216 patients with high-risk or locally advanced prostate cancer who underwent HDR brachytherapy and external beam radiation therapy with long-term androgen deprivation therapy (ADT) between 2003 and 2008 were analyzed. The median prostate-specific antigen (PSA) level at diagnosis was 24 ng/ml (range: 3-338 ng/ml). The clinical stage was T1c-2a in 55 cases (26%), T2b-2c in 48 (22%), T3a in 75 (35%), and T3b-4 in 38 (17%). The mean dose to 90% of the planning target volume was 6.3 Gy/fraction of HDR brachytherapy. After 5 fractions, external beam radiation therapy with 10 fractions of 3 Gy was administered. All patients initially underwent neoadjuvant ADT for at least 6 months, and adjuvant ADT was continued for 36 months. The median follow-up was 7 years from the start of radiotherapy. Results The 7-year PSA relapse-free rate among patients with a post-radiotherapy nPSA level of ≤ 0.02 ng/ml was 94%, compared with 23% for patients with higher nPSA values (HR = 28.57; 95% CI: 12.04-66.66; p < 0.001). Multivariate analysis revealed that the nPSA value after radiotherapy was a significant independent predictor of biochemical failure, whereas pretreatment predictive values for worse biochemical control including higher level of initial PSA, Gleason score ≥ 8, positive biopsy core rate ≥ 67%, and T3b-T4, failed to reach independent predictor status. The 7-year cancer-specific survival rate among patients with a post-radiotherapy nPSA level of ≤ 0.02 ng/ml was 99%, compared with 82% for patients with higher nPSA values (HR = 32.25; 95% CI: 3.401-333.3; p = 0.002). Conclusions A post-radiotherapy nPSA value of ≤ 0.02 ng/ml was associated with better long-term biochemical tumor control even if patients had pretreatment predictive values for worse

  19. PSA kinetics after prostate brachytherapy: PSA bounce phenomenon and its implications for PSA doubling time

    SciTech Connect

    Ciezki, Jay P. . E-mail: ciezkij@ccf.org; Reddy, Chandana A.; Garcia, Jorge; Angermeier, Kenneth; Ulchaker, James; Mahadevan, Arul; Chehade, Nabil; Altman, Andrew; Klein, Eric A.

    2006-02-01

    Purpose: To analyze prostate-specific antigen (PSA) kinetics in patients treated with prostate brachytherapy (PI) with a minimum of 5 years of PSA follow-up. Methods and Materials: The records of 162 patients treated with PI for localized prostate cancer with a minimum of 5 years of PSA follow-up were reviewed. A variety of pretreatment and posttreatment variables were examined. Patients were coded as having a PSA bounce if their PSA achieved a nadir, elevated at least 0.2 ng/mL greater than that nadir, and decreased to, or below, the initial nadir. Two definitions of biochemical failure (bF) or biochemical relapse-free survival (bRFS) were used: the classic American Society for Therapeutic Radiology and Oncology consensus definition of three consecutive rises (bF3) and the nadir plus 2 ng/mL definition (bFn+2). Associations between a PSA bounce and the various pre- and posttreatment factors were assessed with logistic regression analysis, and the association between a PSA bounce and bF was examined with the log-rank test. The Mann-Whitney U test was applied to test for differences in the PSA doubling time (PSADT) and the time to a PSA rise between the PSA bounce patients and the bF patients. PSADT was calculated from the nadir to the time of the first PSA rise, because this point is known first in the clinical setting. Results: The 5-year overall bRFS rate was 87% for the bF3 definition and 96% for the bFn+2 definition. A PSA bounce was experienced by 75 patients (46.3%). Patients who experienced a PSA bounce were less likely to have a bF, regardless of the bRFS definition used (bF3: p = 0.0015; bFn+2: p = 0.0040). Among the pre- and posttreatment factors, only younger age predicted for a PSA bounce on multivariate analysis (p = 0.0018). The use of androgen deprivation had no effect on PSA bounce. No difference was found in the PSADT between patients who had a PSA bounce and those with bF. The median PSADT for those with a PSA bounce was 8.3 months vs. 10.3 months

  20. SU-E-J-232: Feasibility of MRI-Based Preplan On Low Dose Rate Prostate Brachytherapy

    SciTech Connect

    Huang, Y; Tward, J; Rassiah-Szegedi, P; Zhao, H; Sarkar, V; Huang, L; Szegedi, M; Kokeny, K; Salter, B

    2015-06-15

    Purpose: To investigate the feasibility of using MRI-based preplan for low dose rate prostate brachytherapy. Methods: 12 patients who received transrectal ultrasound (TRUS) guided prostate brachytherapy with Pd-103 were retrospectively studied. Our care-standard of the TRUS-based preplan served as the control. One or more prostate T2-weighted wide and/or narrow-field of view MRIs obtained within the 3 months prior to the implant were imported into the MIM Symphony software v6.3 (MIM Software Inc., Cleveland, OH) for each patient. In total, 37 MRI preplans (10 different image sequences with average thickness of 4.8mm) were generated. The contoured prostate volume and the seed counts required to achieve adequate dosimetric coverage from TRUS and MRI preplans were compared for each patient. The effects of different MRI sequences and image thicknesses were also investigated statistically using Student’s t-test. Lastly, the nomogram from the MRI preplan and TRUS preplan from our historical treatment data were compared. Results: The average prostate volume contoured on the TRUS and MRI were 26.6cc (range: 12.6∼41.3cc), and 27.4 cc (range: 14.3∼50.0cc), respectively. Axial MRI thicknesses (range: 3.5∼8.1mm) did not significantly affect the contoured volume or the number of seeds required on the preplan (R2 = 0.0002 and 0.0012, respectively). Four of the MRI sequences (AX-T2, AX-T2-Whole-Pelvis, AX-T2-FSE, and AXIALT2- Hi-Res) showed statistically significant better prostate volume agreement with TRUS than the other seven sequences (P <0.01). Nomogram overlay between the MRI and TRUS preplans showed good agreement; indicating volumes contoured on MRI preplan scan reliably predict how many seeds are needed for implant. Conclusion: Although MRI does not allow for determination of the actual implant geometry, it can give reliable volumes for seed ordering purposes. Our future work will investigate if MRI is sufficient to reliably replace TRUS preplanning in patients

  1. EchoSeed Model 6733 Iodine-125 brachytherapy source: Improved dosimetric characterization using the MCNP5 Monte Carlo code

    SciTech Connect

    Mosleh-Shirazi, M. A.; Hadad, K.; Faghihi, R.; Baradaran-Ghahfarokhi, M.; Naghshnezhad, Z.; Meigooni, A. S.

    2012-08-15

    This study primarily aimed to obtain the dosimetric characteristics of the Model 6733 {sup 125}I seed (EchoSeed) with improved precision and accuracy using a more up-to-date Monte-Carlo code and data (MCNP5) compared to previously published results, including an uncertainty analysis. Its secondary aim was to compare the results obtained using the MCNP5, MCNP4c2, and PTRAN codes for simulation of this low-energy photon-emitting source. The EchoSeed geometry and chemical compositions together with a published {sup 125}I spectrum were used to perform dosimetric characterization of this source as per the updated AAPM TG-43 protocol. These simulations were performed in liquid water material in order to obtain the clinically applicable dosimetric parameters for this source model. Dose rate constants in liquid water, derived from MCNP4c2 and MCNP5 simulations, were found to be 0.993 cGyh{sup -1} U{sup -1} ({+-}1.73%) and 0.965 cGyh{sup -1} U{sup -1} ({+-}1.68%), respectively. Overall, the MCNP5 derived radial dose and 2D anisotropy functions results were generally closer to the measured data (within {+-}4%) than MCNP4c and the published data for PTRAN code (Version 7.43), while the opposite was seen for dose rate constant. The generally improved MCNP5 Monte Carlo simulation may be attributed to a more recent and accurate cross-section library. However, some of the data points in the results obtained from the above-mentioned Monte Carlo codes showed no statistically significant differences. Derived dosimetric characteristics in liquid water are provided for clinical applications of this source model.

  2. Greater Biopsy Core Number Is Associated With Improved Biochemical Control in Patients Treated With Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Wallner, Kent E.

    2010-11-15

    Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores ({<=}6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and {<=}6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy.

  3. MRI characterization of cobalt dichloride-N-acetyl cysteine (C4) contrast agent marker for prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Lim, Tze Yee; Stafford, R. Jason; Kudchadker, Rajat J.; Sankaranarayanapillai, Madhuri; Ibbott, Geoffrey; Rao, Arvind; Martirosyan, Karen S.; Frank, Steven J.

    2014-05-01

    Brachytherapy, a radiotherapy technique for treating prostate cancer, involves the implantation of numerous radioactive seeds into the prostate. While the implanted seeds can be easily identified on a computed tomography image, distinguishing the prostate and surrounding soft tissues is not as straightforward. Magnetic resonance imaging (MRI) offers superior anatomical delineation, but the seeds appear as dark voids and are difficult to identify, thus creating a conundrum. Cobalt dichloride-N-acetyl-cysteine (C4) has previously been shown to be promising as an encapsulated contrast agent marker. We performed spin-lattice relaxation time (T1) and spin-spin relaxation time (T2) measurements of C4 solutions with varying cobalt dichloride concentrations to determine the corresponding relaxivities, r1 and r2. These relaxation parameters were investigated at different field strengths, temperatures and orientations. T1 measurements obtained at 1.5 and 3.0 T, as well as at room and body temperature, showed that r1 is field-independent and temperature-independent. Conversely, the T2 values at 3.0 T were shorter than at 1.5 T, while the T2 values at body temperature were slightly higher than at room temperature. By examining the relaxivities with the C4 vials aligned in three different planes, we found no orientation-dependence. With these relaxation characteristics, we aim to develop pulse sequences that will enhance the C4 signal against prostatic stroma. Ultimately, the use of C4 as a positive contrast agent marker will encourage the use of MRI to obtain an accurate representation of the radiation dose delivered to the prostate and surrounding normal anatomical structures.

  4. Long-Term Outcome and Toxicity of Salvage Brachytherapy for Local Failure After Initial Radiotherapy for Prostate Cancer

    SciTech Connect

    Burri, Ryan J.; Stone, Nelson N.; Unger, Pam; Stock, Richard G.

    2010-08-01

    Purpose: To describe long-term outcomes and toxicity after salvage brachytherapy (BT) for local failure after initial radiotherapy for prostate cancer. Methods and Materials: Between 1994 and 2008, 37 men with local failure after initial prostate radiotherapy (32 external-beam radiation therapy [EBRT] and 5 BT) underwent salvage BT with {sup 103}Pd or {sup 125}I. Estimates of freedom from biochemical failure (FFbF, Phoenix definition) and cause-specific survival (CSS) were calculated using the Kaplan-Meier method. Toxicities were graded using CTCv3.0. Results: Median follow-up was 86 months (range, 2-156). The median dose to 90% of the prostate volume was 122 Gy (range, 67-166). The 10-year FFbF and CSS were 54% and 96%, respectively. On univariate analysis, prostate-specific antigen (PSA) >10 ng/mL at initial diagnosis was significantly associated with FFbF (p = 0.01), and there were trends for both age <70 years (p = 0.08) and PSA <6 ng/mL (p = 0.08) at the time of salvage BT. On multivariate analysis, only presalvage PSA <6 ng/mL (p = 0.046) was significantly associated with improved FFbF. There were three Grade 3 toxicities and one Grade 4 toxicity. Pelvic lymph node dissection before salvage BT was the only variable significantly associated with Grade {>=}2 toxicity (p = 0.03). Conclusion: With a median follow-up of 86 months, salvage prostate BT was associated with a 10-year FFbF of 54% and CSS of 96%. Improved FFbF was associated with a presalvage PSA <6 ng/mL. Toxicity was worse in patients who had undergone pelvic lymph node dissection before salvage BT. Careful patient selection for salvage BT may result in improved outcomes and reduced toxicity.

  5. Localization of linked {sup 125}I seeds in postimplant TRUS images for prostate brachytherapy dosimetry

    SciTech Connect

    Xue Jinyu . E-mail: Jinyu.Xue@mail.tju.edu; Waterman, Frank; Handler, Jay; Gressen, Eric

    2005-07-01

    Purpose: To demonstrate that {sup 125}I seeds can be localized in transrectal ultrasound (TRUS) images obtained with a high-resolution probe when the implant is performed with linked seeds and spacers. Adequate seed localization is essential to the implementation of TRUS-based intraoperative dosimetry for prostate brachytherapy. Methods and Materials: Thirteen preplanned peripherally loaded prostate implants were performed using {sup 125}I seeds and spacers linked together in linear arrays that prevent seed migration and maintain precise seed spacing. A set of two-dimensional transverse images spaced at 0.50-cm intervals were obtained with a high-resolution TRUS probe at the conclusion of the procedure with the patient still under anesthesia. The image set extended from 1.0 cm superior to the base to 1.0 cm inferior to the apex. The visible echoes along each needle track were first localized and then compared with the known construction of the implanted array. The first step was to define the distal and proximal ends of each array. The visible echoes were then identified as seeds or spacers from the known sequence of the array. The locations of the seeds that did not produce a visible echo were interpolated from their known position in the array. A CT scan was obtained after implantation for comparison with the TRUS images. Results: On average, 93% (range, 86-99%) of the seeds were visible in the TRUS images. However, it was possible to localize 100% of the seeds in each case, because the locations of the missing seeds could be determined from the known construction of the arrays. Two factors complicated the interpretation of the TRUS images. One was that the spacers also produced echoes. Although weak and diffuse, these echoes could be mistaken for seeds. The other was that the number of echoes along a needle track sometimes exceeded the number of seeds and spacers implanted. This was attributed to the overall length of the array, which was approximately 0.5 cm

  6. Automatic shape-based level set segmentation for needle tracking in 3-D TRUS-guided prostate brachytherapy.

    PubMed

    Yan, Ping; Cheeseborough, John C; Chao, K S Clifford

    2012-09-01

    Prostate brachytherapy is an effective treatment for early prostate cancer. The success depends critically on the correct needle implant positions. We have devised an automatic shape-based level set segmentation tool for needle tracking in 3-D transrectal ultrasound (TRUS) images, which uses the shape information and level set technique to localize the needle position and estimate the endpoint of needle in real-time. The 3-D TRUS images used in the evaluation of our tools were obtained using a 2-D TRUS transducer from Ultrasonix (Richmond, BC, Canada) and a computer-controlled stepper motor system from Thorlabs (Newton, NJ, USA). The accuracy and feedback mechanism had been validated using prostate phantoms and compared with 3-D positions of these needles derived from experts' readings. The experts' segmentation of needles from 3-D computed tomography images was the ground truth in this study. The difference between automatic and expert segmentations are within 0.1 mm for 17 of 19 implanted needles. The mean errors of automatic segmentations by comparing with the ground truth are within 0.25 mm. Our automated method allows real-time TRUS-based needle placement difference within one pixel compared with manual expert segmentation.

  7. The investigation of prostatic calcifications using μ-PIXE analysis and their dosimetric effect in low dose rate brachytherapy treatments using Geant4

    NASA Astrophysics Data System (ADS)

    Pope, D. J.; Cutajar, D. L.; George, S. P.; Guatelli, S.; Bucci, J. A.; Enari, K. E.; Miller, S.; Siegele, R.; Rosenfeld, A. B.

    2015-06-01

    Low dose rate brachytherapy is a widely used modality for the treatment of prostate cancer. Most clinical treatment planning systems currently in use approximate all tissue to water, neglecting the existence of inhomogeneities, such as calcifications. The presence of prostatic calcifications may perturb the dose due to the higher photoelectric effect cross section in comparison to water. This study quantitatively evaluates the effect of prostatic calcifications on the dosimetric outcome of brachytherapy treatments by means of Monte Carlo simulations and its potential clinical consequences. Four pathological calcification samples were characterised with micro-particle induced x-ray emission (μ-PIXE) to determine their heavy elemental composition. Calcium, phosphorus and zinc were found to be the predominant heavy elements in the calcification composition. Four clinical patient brachytherapy treatments were modelled using Geant4 based Monte Carlo simulations, in terms of the distribution of brachytherapy seeds and calcifications in the prostate. Dose reductions were observed to be up to 30% locally to the calcification boundary, calcification size dependent. Single large calcifications and closely placed calculi caused local dose reductions of between 30-60%. Individual calculi smaller than 0.5 mm in diameter showed minimal dosimetric impact, however, the effects of small or diffuse calcifications within the prostatic tissue could not be determined using the methods employed in the study. The simulation study showed a varying reduction on common dosimetric parameters. D90 showed a reduction of 2-5%, regardless of calcification surface area and volume. The parameters V100, V150 and V200 were also reduced by as much as 3% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications, which may have a significant dosimetric impact on brachytherapy treatment, however, such impacts depend strongly on specific factors

  8. The investigation of prostatic calcifications using μ-PIXE analysis and their dosimetric effect in low dose rate brachytherapy treatments using Geant4.

    PubMed

    Pope, D J; Cutajar, D L; George, S P; Guatelli, S; Bucci, J A; Enari, K E; Miller, S; Siegele, R; Rosenfeld, A B

    2015-06-01

    Low dose rate brachytherapy is a widely used modality for the treatment of prostate cancer. Most clinical treatment planning systems currently in use approximate all tissue to water, neglecting the existence of inhomogeneities, such as calcifications. The presence of prostatic calcifications may perturb the dose due to the higher photoelectric effect cross section in comparison to water. This study quantitatively evaluates the effect of prostatic calcifications on the dosimetric outcome of brachytherapy treatments by means of Monte Carlo simulations and its potential clinical consequences.Four pathological calcification samples were characterised with micro-particle induced x-ray emission (μ-PIXE) to determine their heavy elemental composition. Calcium, phosphorus and zinc were found to be the predominant heavy elements in the calcification composition. Four clinical patient brachytherapy treatments were modelled using Geant4 based Monte Carlo simulations, in terms of the distribution of brachytherapy seeds and calcifications in the prostate. Dose reductions were observed to be up to 30% locally to the calcification boundary, calcification size dependent. Single large calcifications and closely placed calculi caused local dose reductions of between 30-60%. Individual calculi smaller than 0.5 mm in diameter showed minimal dosimetric impact, however, the effects of small or diffuse calcifications within the prostatic tissue could not be determined using the methods employed in the study. The simulation study showed a varying reduction on common dosimetric parameters. D90 showed a reduction of 2-5%, regardless of calcification surface area and volume. The parameters V100, V150 and V200 were also reduced by as much as 3% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications, which may have a significant dosimetric impact on brachytherapy treatment, however, such impacts depend strongly on specific factors

  9. Metformin is not associated with improved biochemical free survival or cause-specific survival in men with prostate cancer treated with permanent interstitial brachytherapy

    PubMed Central

    Taira, Al V.; Galbreath, Robert W.; Morris, Mallory; Butler, Wayne M.; Adamovich, Edward

    2014-01-01

    Purpose Several recent studies have suggested improved clinical outcomes in diabetic men with prostate cancer who also use metformin. We explore whether metformin use is associated with improved outcomes specifically in men undergoing prostate brachytherapy. Material and methods 2,298 consecutive patients underwent permanent interstitial brachytherapy by a single brachytherapist (GSM). The cohort included 2028 non-diabetic men, 144 men with diabetes who were not taking metformin, and 126 men with diabetes who were taking metformin. Median follow up was 8.3 years. Differences in biochemical free survival, cause specific survival, and overall survival between men taking metformin and those not taking metformin were compared using Kaplan-Meier curves and log rank tests. Results Fifteen year biochemical failure rate, cause specific mortality and overall mortality for non-diabetic men was 4.6%, 1.5%, 47.0%, respectively; for diabetic men taking metformin 4.8%, 2.0%, 37.2%; and for diabetic men not taking metformin was 2.8%, 0%, 72.7%, respectively. Metformin use was not predictive in multivariate analysis of biochemical failure or prostate cancer specific mortality. However, diabetic men not taking metformin had higher overall mortality than non-diabetic men. Conclusions Metformin use was not associated with improved biochemical survival or cancer specific survival in this cohort of men treated with prostate brachytherapy. PMID:25337126

  10. MRI Signal Intensity Based B-Spline Nonrigid Registration for Pre- and Intraoperative Imaging During Prostate Brachytherapy

    PubMed Central

    Oguro, Sota; Tokuda, Junichi; Elhawary, Haytham; Haker, Steven; Kikinis, Ron; Tempany, Clare M.C.; Hata, Nobuhiko

    2009-01-01

    Purpose To apply an intensity-based nonrigid registration algorithm to MRI-guided prostate brachytherapy clinical data and to assess its accuracy. Materials and Methods A nonrigid registration of preoperative MRI to intraoperative MRI images was carried out in 16 cases using a Basis-Spline algorithm in a retrospective manner. The registration was assessed qualitatively by experts’ visual inspection and quantitatively by measuring the Dice similarity coefficient (DSC) for total gland (TG), central gland (CG), and peripheral zone (PZ), the mutual information (MI) metric, and the fiducial registration error (FRE) between corresponding anatomical landmarks for both the nonrigid and a rigid registration method. Results All 16 cases were successfully registered in less than 5 min. After the nonrigid registration, DSC values for TG, CG, PZ were 0.91, 0.89, 0.79, respectively, the MI metric was −0.19 ± 0.07 and FRE presented a value of 2.3 ± 1.8 mm. All the metrics were significantly better than in the case of rigid registration, as determined by one-sided t-tests. Conclusion The intensity-based nonrigid registration method using clinical data was demonstrated to be feasible and showed statistically improved metrics when compare to only rigid registration. The method is a valuable tool to integrate pre- and intraoperative images for brachytherapy. PMID:19856437

  11. Pretreatment Serum Testosterone and Androgen Deprivation: Effect on Disease Recurrence and Overall Survival in Prostate Cancer Patients Treated With Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Lief, Jonathan H.; Adamovich, Edward

    2009-07-15

    Purpose: Low testosterone has been implicated as a possible adverse prognostic factor in patients with newly diagnosed prostate cancer. We evaluated the impact of pretreatment serum testosterone on survival after prostate brachytherapy. Methods and Materials: From October 2001 to November 2004, 619 patients underwent brachytherapy and 546 had a pretreatment serum testosterone level measured. Pretreatment serum testosterone levels were assigned by the following criteria: below-normal (n = 105), low normal (n = 246), mid normal (n = 132), high normal (n = 50), and above normal (n = 13). Median follow-up was 5.2 years. Cause of death was determined for each deceased patient. Results: Six-year biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were 97.7%, 99.8%, and 89.2%. When comparing patients with low or low normal testosterone with those with average or higher testosterone, there was no significant difference in bPFS (97.6% vs. 98.4%; p = 0.72), CSS (99.8% vs. 100%; p = 0.72), or OS (88.9% vs. 90.8%; p = 0.73). Among patients with average and higher pretreatment testosterone, there was no significant difference in outcomes when comparing patients who did and did not receive androgen deprivation therapy (ADT). For patients with low or low normal testosterone levels, there was no significant difference in bPFS or CSS when comparing patients who did and did not receive ADT. However, there was a trend toward lower OS in patients with baseline lower testosterone levels who also received ADT (83.9% vs. 91.3%, p = 0.075). Conclusions: Low pretreatment testosterone levels alone did not affect disease recurrence or OS. Patients with baseline low testosterone who also were treated with ADT had a trend toward decreased OS.

  12. A Genetically Determined Dose-Volume Histogram Predicts for Rectal Bleeding among Patients Treated With Prostate Brachytherapy

    SciTech Connect

    Cesaretti, Jamie A. . E-mail: jamie.cesaretti@msnyuhealth.org; Stock, Richard G.; Atencio, David P.; Peters, Sheila A.; Peters, Christopher A.; Burri, Ryan J.; Stone, Nelson N.; Rosenstein, Barry S.

    2007-08-01

    Purpose: To examine whether possession of genetic alterations in the ATM (ataxia telangiectasia) gene is associated with rectal bleeding in a dose-dependent and volume-dependent manner. Methods and Materials: One hundred eight prostate cancer patients who underwent brachytherapy using either an {sup 125}I implant, a {sup 103}Pd implant, or the combination of external beam radiotherapy with a {sup 103}Pd implant and had a minimum of 1 year follow-up were screened for DNA sequence variations in the 62 coding exons of the ATM gene using denaturing high-performance liquid chromatography. Rectal dose was reported as the volume (in cubic centimeters) of rectum receiving the brachytherapy prescription dose. The two-sided Fisher exact test was used to compare differences in proportions. Results: A significant correlation between the presence of any ATM sequence alteration and Grade 1 to 2 proctitis was obtained when the radiation dose to rectal tissue was quantified. Rectal bleeding occurred in 4 of 13 patients (31%) with a variant versus 1 of 23 (4%) without a genetic alteration for patients who had <0.7 cm{sup 3} of rectal tissue receiving the implant prescription dose (p = 0.05). Of patients in whom 0.7-1.4 cm{sup 3} of the rectum received the implant prescription, 4 of 11 (36%) with an ATM alteration exhibited Grade 1 to 2 proctitis, whereas 1 of 21 (5%) without a variant (p = 0.04) developed this radiation-induced late effect. Conclusions: The possession of genetic variants in the ATM gene is associated with the development of radiation-induced proctitis after prostate cancer radiotherapy for patients who receive the full prescription dose to either a low or a moderate volume of rectal tissue.

  13. Incidence of Secondary Cancer Development After High-Dose Intensity-Modulated Radiotherapy and Image-Guided Brachytherapy for the Treatment of Localized Prostate Cancer

    SciTech Connect

    Zelefsky, Michael J.; Housman, Douglas M.; Pei Xin; Alicikus, Zumre; Magsanoc, Juan Martin; Dauer, Lawrence T.; St Germain, Jean; Yamada, Yoshiya; Kollmeier, Marisa; Cox, Brett; Zhang Zhigang

    2012-07-01

    Purpose: To report the incidence and excess risk of second malignancy (SM) development compared with the general population after external beam radiotherapy (EBRT) and brachytherapy to treat prostate cancer. Methods and Materials: Between 1998 and 2001, 1,310 patients with localized prostate cancer were treated with EBRT (n = 897) or brachytherapy (n = 413). We compared the incidence of SMs in our patients with that of the general population extracted from the National Cancer Institute's Surveillance, Epidemiology, and End Results data set combined with the 2000 census data. Results: The 10-year likelihood of SM development was 25% after EBRT and 15% after brachytherapy (p = .02). The corresponding 10-year likelihood for in-field SM development in these groups was 4.9% and 1.6% (p = .24). Multivariate analysis showed that EBRT vs. brachytherapy and older age were the only significant predictors for the development of all SMs (p = .037 and p = .030), with a trend for older patients to develop a SM. The increased incidence of SM for EBRT patients was explained by the greater incidence of skin cancer outside the radiation field compared with that after brachytherapy (10.6% and 3.3%, respectively, p = .004). For the EBRT group, the 5- and 10-year mortality rate was 1.96% and 5.1% from out-of field cancer, respectively; for in-field SM, the corresponding mortality rates were 0.1% and 0.7%. Among the brachytherapy group, the 5- and 10-year mortality rate related to out-of field SM was 0.8% and 2.7%, respectively. Our observed SM rates after prostate RT were not significantly different from the cancer incidence rates in the general population. Conclusions: Using modern sophisticated treatment techniques, we report low rates of in-field bladder and rectal SM risks after prostate cancer RT. Furthermore, the likelihood of mortality secondary to a SM was unusual. The greater rate of SM observed with EBRT vs. brachytherapy was related to a small, but significantly increased

  14. Dosimetric Comparison of High-Dose-Rate Brachytherapy and Intensity-Modulated Radiation Therapy as a Boost to the Prostate

    SciTech Connect

    Hermesse, Johanne; Biver, Sylvie; Jansen, Nicolas; Lenaerts, Eric; Nickers, Philippe

    2010-01-15

    Purpose: We compared the dose conformity of two radiation modalities: high-dose-rate brachytherapy (HDR BT) and intensity-modulated radiation therapy (IMRT) to deliver a boost to the prostate after external beam radiotherapy (EBRT). Methods and Materials: Ten successive patients with prostate adenocarcinoma treated with a single 10-Gy HDR BT boost after EBRT were investigated. Four theoretical IMRT plans were computed: (a) 32.85 Gy IMRT and (b) 26 Gy IMRT with CTV-PTV expansions, doses corresponding to the equivalent dose in 2-Gy fractions (EQD2) of one 10-Gy fraction calculated with a prostate alpha/beta ratio of respectively 1.5 and 3 Gy; and (c) 32.85 Gy IMRT and (d) 26 Gy IMRT without CTV-PTV expansions. The dose-volume histogram values converted in EQD2 with an alpha/beta ratio of 3 Gy for the organs at risk were compared. Results: The HDR BT plan delivered higher mean doses to the PTV compared with IMRT plans. In all, 33% of the rectal volume received a mean dose of 5.32 +- 0.65 Gy and 20% of bladder volume received 4.61 +- 1.24 Gy with HDR BT. In comparison, doses delivered with IMRT were respectively 13.4 +- 1.49 Gy and 10.81 +- 4 Gy, even if only 26 Gy was prescribed to the PTV with no CTV-PTV expansion (p < 0.0001). The hot spots inside the urethra were greater with HDR BT but acceptable. Conclusions: Use of HDR BT produced a more conformal plan for the boost to the prostate than IMRT even without CTV-PTV expansions.

  15. Prophylactic tamsulosin (Flomax) in patients undergoing prostate {sup 125}I brachytherapy for prostate carcinoma: Final report of a double-blind placebo-controlled randomized study

    SciTech Connect

    Elshaikh, Mohamed A.; Ulchaker, James C.; Reddy, Chandana A.; Angermeier, Kenneth W.; Klein, Eric A.; Chehade, Nabil; Altman, Andrew; Ciezki, Jay P. . E-mail: ciezkj@ccf.org

    2005-05-01

    Purpose: To evaluate the effectiveness of prophylactic tamsulosin (Flomax) in reducing the urinary symptoms in patients undergoing {sup 125}I prostate implantation (PI) for prostate adenocarcinoma. Methods and materials: This is a single-institution, double-blind, placebo-controlled, randomized trial for patients undergoing PI for prostate adenocarcinoma comparing prophylactic tamsulosin versus placebo. Eligibility criteria included patients not taking tamsulosin or other {alpha}-blockers treated with PI. The patients were randomly assigned to either tamsulosin (0.8 mg, orally once a day) or matched placebo. All patients started the medication 4 days before PI and continued for 60 days. The American Urologic Association (AUA) symptom index questionnaire was used to assess urinary symptoms. The AUA questionnaire was administered before PI for a baseline score and weekly for 8 weeks after PI. Patients were taken off the study if they developed urinary retention, had intolerable urinary symptoms, or wished to discontinue with the trial. Results: One hundred twenty-six patients were enrolled in this study from November 2001 to January 2003 (118 were evaluable: 58 in the tamsulosin arm and 60 in the placebo group). Pretreatment and treatment characteristics were comparably matched between the two groups. The urinary retention rate was 17% (10 patients) in the placebo group compared with 10% (6 patients) in the tamsulosin group (p = 0.3161). Eighty-eight percent (14 patients) of those who developed urinary retention experienced it within 2 weeks after the PI. Intolerable urinary symptoms were reported equally (10 patients in each group) with 70% occurring in the first 2 weeks after PI. There was a significant difference in mean AUA score in favor of tamsulosin at Week 5 after PI (p = 0.03). Conclusions: Prophylactic tamsulosin (0.8 mg/day) before prostate brachytherapy did not significantly affect urinary retention rates, but had a positive effect on urinary morbidity at

  16. Iodine-125 seed implantation as an adjunct to surgery in advanced recurrent squamous cell cancer of the head and neck

    SciTech Connect

    Park, R.I.; Liberman, F.Z.; Lee, D.J.; Goldsmith, M.M.; Price, J.C. )

    1991-04-01

    Survival for extensive recurrent squamous cell carcinomas of the head and neck remains poor, with the major cause of death being local recurrence. Surgical implantation of iodine-125 interstitial seeds allows tumoricidal doses of radiation to be delivered to residual tumor while minimizing radiation doses to the surrounding tissues. From 1978 to 1988, 39 implantations were performed on 35 patients for extensive recurrent squamous cell carcinoma of the head and neck. The decision for implantation was based on positive margins or close to resection margins from frozen sections after salvage resection. The determinate 5-year disease-free survival was 41%, with both the overall and no evidence of disease 5-year survivals being 29%. Significant complications occurred in 36% of all cases. This figure increased to 56% when flap reconstruction was required. Possible reasons for this seemingly high complication rate are discussed. Considering the advanced nature of these recurrent carcinomas, surgical resection with iodine-125 seed implantation appears to be an effective method of managing disease that might otherwise be judged unresectable and treated for palliation only.

  17. 15-Year biochemical relapse free survival in clinical Stage T1-T3 prostate cancer following combined external beam radiotherapy and brachytherapy; Seattle experience

    SciTech Connect

    Sylvester, John E. . E-mail: johnsylvester@seattleprostate.com; Grimm, Peter D.; Blasko, John C.; Millar, Jeremy; Orio, Peter F.; Skoglund, Scott; Galbreath, Robert W.; Merrick, Gregory

    2007-01-01

    Purpose: Long-term biochemical relapse-free survival (BRFS) rates in patients with clinical Stages T1-T3 prostate cancer continue to be scrutinized after treatment with external beam radiation therapy and brachytherapy. Methods and Materials: We report 15-year BRFS rates on 223 patients with clinically localized prostate cancer that were consecutively treated with I{sup 125} or Pd {sup 103} brachytherapy after 45-Gy neoadjuvant EBRT. Multivariate regression analysis was used to create a pretreatment clinical prognostic risk model using a modified American Society for Therapeutic Radiology and Oncology consensus definition (two consecutive serum prostate-specific antigen rises) as the outcome. Gleason scoring was performed by the pathologists at a community hospital. Time to biochemical failure was calculated and compared by using Kaplan-Meier plots. Results: Fifteen-year BRFS for the entire treatment group was 74%. BRFS using the Memorial Sloan-Kettering risk cohort analysis (95% confidence interval): low risk, 88%, intermediate risk 80%, and high risk 53%. Grouping by the risk classification described by D'Amico, the BRFS was: low risk 85.8%, intermediate risk 80.3%, and high risk 67.8% (p = 0.002). Conclusions: I{sup 125} or Pd{sup 103} brachytherapy combined with supplemental EBRT results in excellent 15-year biochemical control. Different risk group classification schemes lead to different BRFS results in the high-risk group cohorts.

  18. A radiobiology-based inverse treatment planning method for optimisation of permanent l-125 prostate implants in focal brachytherapy

    NASA Astrophysics Data System (ADS)

    Haworth, Annette; Mears, Christopher; Betts, John M.; Reynolds, Hayley M.; Tack, Guido; Leo, Kevin; Williams, Scott; Ebert, Martin A.

    2016-01-01

    Treatment plans for ten patients, initially treated with a conventional approach to low dose-rate brachytherapy (LDR, 145 Gy to entire prostate), were compared with plans for the same patients created with an inverse-optimisation planning process utilising a biologically-based objective. The ‘biological optimisation’ considered a non-uniform distribution of tumour cell density through the prostate based on known and expected locations of the tumour. Using dose planning-objectives derived from our previous biological-model validation study, the volume of the urethra receiving 125% of the conventional prescription (145 Gy) was reduced from a median value of 64% to less than 8% whilst maintaining high values of TCP. On average, the number of planned seeds was reduced from 85 to less than 75. The robustness of plans to random seed displacements needs to be carefully considered when using contemporary seed placement techniques. We conclude that an inverse planning approach to LDR treatments, based on a biological objective, has the potential to maintain high rates of tumour control whilst minimising dose to healthy tissue. In future, the radiobiological model will be informed using multi-parametric MRI to provide a personalised medicine approach.

  19. TU-F-BRF-02: MR-US Prostate Registration Using Patient-Specific Tissue Elasticity Property Prior for MR-Targeted, TRUS-Guided HDR Brachytherapy

    SciTech Connect

    Yang, X; Rossi, P; Ogunleye, T; Jani, A; Curran, W; Liu, T

    2014-06-15

    Purpose: High-dose-rate (HDR) brachytherapy has become a popular treatment modality for prostate cancer. Conventional transrectal ultrasound (TRUS)-guided prostate HDR brachytherapy could benefit significantly from MR-targeted, TRUS-guided procedure where the tumor locations, acquired from the multiparametric MRI, are incorporated into the treatment planning. In order to enable this integration, we have developed a MR-TRUS registration with a patient-specific biomechanical elasticity prior. Methods: The proposed method used a biomechanical elasticity prior to guide the prostate volumetric B-spline deformation in the MRI and TRUS registration. The patient-specific biomechanical elasticity prior was generated using ultrasound elastography, where two 3D TRUS prostate images were acquired under different probe-induced pressures during the HDR procedure, which takes 2-4 minutes. These two 3D TRUS images were used to calculate the local displacement (elasticity map) of two prostate volumes. The B-spline transformation was calculated by minimizing the Euclidean distance between the normalized attribute vectors of the prostate surface landmarks on the MR and TRUS. This technique was evaluated through two studies: a prostate-phantom study and a pilot study with 5 patients undergoing prostate HDR treatment. The accuracy of our approach was assessed through the locations of several landmarks in the post-registration and TRUS images; our registration results were compared with the surface-based method. Results: For the phantom study, the mean landmark displacement of the proposed method was 1.29±0.11 mm. For the 5 patients, the mean landmark displacement of the surface-based method was 3.25±0.51 mm; our method, 1.71±0.25 mm. Therefore, our proposed method of prostate registration outperformed the surfaced-based registration significantly. Conclusion: We have developed a novel MR-TRUS prostate registration approach based on patient-specific biomechanical elasticity prior

  20. High-Dose-Rate Interstitial Brachytherapy as Monotherapy for Clinically Localized Prostate Cancer: Treatment Evolution and Mature Results

    SciTech Connect

    Zamboglou, Nikolaos; Tselis, Nikolaos; Baltas, Dimos; Buhleier, Thomas; Martin, Thomas; Milickovic, Natasa; Papaioannou, Sokratis; Ackermann, Hanns; Tunn, Ulf W.

    2013-03-01

    Purpose: To report the clinical outcome of high-dose-rate (HDR) interstitial (IRT) brachytherapy (BRT) as sole treatment (monotherapy) for clinically localized prostate cancer. Methods and Materials: Between January 2002 and December 2009, 718 consecutive patients with clinically localized prostate cancer were treated with transrectal ultrasound (TRUS)-guided HDR monotherapy. Three treatment protocols were applied; 141 patients received 38.0 Gy using one implant in 4 fractions of 9.5 Gy with computed tomography-based treatment planning; 351 patients received 38.0 Gy in 4 fractions of 9.5 Gy, using 2 implants (2 weeks apart) and intraoperative TRUS real-time treatment planning; and 226 patients received 34.5 Gy, using 3 single-fraction implants of 11.5 Gy (3 weeks apart) and intraoperative TRUS real-time treatment planning. Biochemical failure was defined according to the Phoenix consensus, and toxicity was evaluated using Common Toxicity Criteria for Adverse Events version 3. Results: The median follow-up time was 52.8 months. The 36-, 60-, and 96-month biochemical control and metastasis-free survival rates for the entire cohort were 97%, 94%, and 90% and 99%, 98%, and 97%, respectively. Toxicity was scored per event, with 5.4% acute grade 3 genitourinary and 0.2% acute grade 3 gastrointestinal toxicity. Late grade 3 genitourinary and gastrointestinal toxicities were 3.5% and 1.6%, respectively. Two patients developed grade 4 incontinence. No other instance of grade 4 or greater acute or late toxicity was reported. Conclusion: Our results confirm IRT-HDR-BRT is safe and effective as monotherapy for clinically localized prostate cancer.

  1. 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.

  2. Pretreatment Endorectal Coil Magnetic Resonance Imaging Findings Predict Biochemical Tumor Control in Prostate Cancer Patients Treated With Combination Brachytherapy and External-Beam Radiotherapy

    SciTech Connect

    Riaz, Nadeem; Afaq, Asim; Akin, Oguz; Pei Xin; Kollmeier, Marisa A.; Cox, Brett; Hricak, Hedvig; Zelefsky, Michael J.

    2012-11-01

    Purpose: To investigate the utility of endorectal coil magenetic resonance imaging (eMRI) in predicting biochemical relapse in prostate cancer patients treated with combination brachytherapy and external-beam radiotherapy. Methods and Materials: Between 2000 and 2008, 279 men with intermediate- or high-risk prostate cancer underwent eMRI of their prostate before receiving brachytherapy and supplemental intensity-modulated radiotherapy. Endorectal coil MRI was performed before treatment and retrospectively reviewed by two radiologists experienced in genitourinary MRI. Image-based variables, including tumor diameter, location, number of sextants involved, and the presence of extracapsular extension (ECE), were incorporated with other established clinical variables to predict biochemical control outcomes. The median follow-up was 49 months (range, 1-13 years). Results: The 5-year biochemical relapse-free survival for the cohort was 92%. Clinical findings predicting recurrence on univariate analysis included Gleason score (hazard ratio [HR] 3.6, p = 0.001), PSA (HR 1.04, p = 0.005), and National Comprehensive Cancer Network risk group (HR 4.1, p = 0.002). Clinical T stage and the use of androgen deprivation therapy were not correlated with biochemical failure. Imaging findings on univariate analysis associated with relapse included ECE on MRI (HR 3.79, p = 0.003), tumor size (HR 2.58, p = 0.04), and T stage (HR 1.71, p = 0.004). On multivariate analysis incorporating both clinical and imaging findings, only ECE on MRI and Gleason score were independent predictors of recurrence. Conclusions: Pretreatment eMRI findings predict for biochemical recurrence in intermediate- and high-risk prostate cancer patients treated with combination brachytherapy and external-beam radiotherapy. Gleason score and the presence of ECE on MRI were the only significant predictors of biochemical relapse in this group of patients.

  3. Local Control Following Permanent Prostate Brachytherapy: Effect of High Biologically Effective Dose on Biopsy Results and Oncologic Outcomes

    SciTech Connect

    Stone, Nelson N.; Stock, Richard G.; Cesaretti, Jamie A.; Unger, Pam

    2010-02-01

    Purpose: To determine factors that influence local control and systemic relapse in patients undergoing permanent prostate brachytherapy (PPB). Methods and Materials: A total of 584 patients receiving PPB alone or PPB with external beam radiation therapy (19.5%) agreed to undergo prostate biopsy (PB) at 2 years postimplantion and yearly if results were positive or if the prostate-specific antigen (PSA) level increased. Short-term hormone therapy was used with 280 (47.9%) patients. Radiation doses were converted to biologically effective doses (BED) (using alpha/beta = 2). Comparisons were made by chi-square analysis and linear regression. Survival was determined by the Kaplan-Meier method. Results: The median PSA concentration was 7.1 ng/ml, and the median follow-up period was 7.1 years. PB results were positive for 48/584 (8.2%) patients. Positive biopsy results by BED group were as follows: 22/121 (18.2%) patients received a BED of <=150 Gy; 15/244 (6.1%) patients received >150 to 200 Gy; and 6/193 (3.1%; p < 0.001) patients received >200 Gy. Significant associations of positive PB results by risk group were low-risk group BED (p = 0.019), intermediate-risk group hormone therapy (p = 0.011) and BED (p = 0.040), and high-risk group BED (p = 0.004). Biochemical freedom from failure rate at 7 years was 82.7%. Biochemical freedom from failure rate by PB result was 84.7% for negative results vs. 59.2% for positive results (p < 0.001). Cox regression analysis revealed significant associations with BED (p = 0.038) and PB results (p = 0.002) in low-risk patients, with BED (p = 0.003) in intermediate-risk patients, and with Gleason score (p = 0.006), PSA level (p < 0.001), and PB result (p = 0.038) in high-risk patients. Fifty-three (9.1%) patients died, of which eight deaths were due to prostate cancer. Cause-specific survival was 99.2% for negative PB results vs. 87.6% for positive PB results (p < 0.001). Conclusions: Higher radiation doses are required to achieve local

  4. Prostate-Specific Antigen at 4 to 5 Years After Low-Dose-Rate Prostate Brachytherapy Is a Strong Predictor of Disease-Free Survival

    SciTech Connect

    Lo, Andrea C.; Morris, W. James; Lapointe, Vincent; Hamm, Jeremy; Keyes, Mira; Pickles, Tom; McKenzie, Michael; Spadinger, Ingrid

    2014-01-01

    Purpose: To determine (1) the prognostic utility of prostate-specific antigen (PSA) concentration at 45 to 60 months (48mPSA) after low-dose-rate prostate brachytherapy (LDR-PB); (2) the predictors of 48mPSA; and (3) the prognostic utility of directional trends between PSA levels at 24, 36, and 48 months after LDR-PB. Methods and Materials: Between 1998 and 2008, 2223 patients with low- and intermediate-risk prostate cancer received LDR-PB monotherapy. A cohort of 1434 of these patients was identified with a documented 48mPSA and no evidence of disease relapse prior to the 48mPSA. In addition, a subset of this cohort (n=585) was identified with ≥72 months of follow-up and documented PSA values at both 24 and 36 months after implantation. Results: Median follow-up time was 76 months. Eight-year Kaplan-Meier disease-free survival (DFS) rates were 100% vs 73.4% for patients with 48mPSA ≤0.2 vs those with >0.2 ng/mL; 99.1% versus 53.8% for a 48mPSA threshold of ≤0.4 versus >0.4 ng/mL, respectively; and 97.3% versus 0% for a threshold of ≤1.0 versus >1.0 ng/mL, respectively. On multivariate analysis, the only factor predictive of DFS was 48mPSA (P<.0001). On subset analysis (n=585), 29 patients had a PSA rise (defined as >0.2 ng/mL) between 24 and 36 months, 24 patients had a rise between 36 and 48 months, and 11 patients had rises over both intervals. Failure rates in these patients were 52%, 79%, and 100%, respectively. On multivariate analysis, initial PSA, androgen deprivation therapy, and dose to 90% of the prostate significantly correlated with 48mPSA but together accounted for only ∼5% of its total variance. Conclusions: The 48mPSA after LDR-PB is highly predictive of long-term DFS. Patients with 48mPSA ≤0.4 ng/mL had a <1% risk of disease relapse at 8 years, whereas all patients with 48mPSA >1.0 ng/mL relapsed. Consecutive PSA rises of >0.2 ng/mL from 24 to 36 months and from 36 to 48 months were also highly predictive of subsequent failure.

  5. 3D MR-Spectroscopic Imaging Assessment of Metabolic Activity in the Prostate During the PSA 'Bounce' Following {sup 125}Iodine Brachytherapy

    SciTech Connect

    Kirilova, Anna; Damyanovich, Andrei; Crook, Juanita; Jezioranski, John; Wallace, Kris; Pintilie, Melania

    2011-02-01

    Purpose: A temporary increase in prostate-specific antigen (PSA) values is observed in 30%-40% of men following {sup 125} I brachytherapy (BT) for prostate cancer. We present the results of a study to characterize prostate metabolic activity during the PSA 'bounce' and to correlate metabolic changes with PSA levels using three-dimensional magnetic resonance spectroscopic imaging (3D-MRSI). Methods and Materials: 3D-MRSI was performed in 24 patients during the PSA bounce. Eight of these had also had a baseline 3D-MRSI scan before BT for the purpose of tumor mapping. The 3D-MRSI was repeated at 6- and 12-month intervals, and PSA levels were monitored every 3 months. Twenty-one of the patients had favorable-risk prostate cancer, and 3 had intermediate risk. Results: The choline+creatine signal intensity, although markedly reduced, was observable following BT. Diffuse activity not corresponding to original biopsy-positive sites was observed in 22 cases, and 2 cases were documented to have local recurrence. No statistically significant correlation between metabolic activity and PSA levels at each interval was found. Conclusion: Post-BT prostate 3D-MRSI shows evidence of diffuse metabolic activity unrelated to residual malignancy. This supports the benign nature of the PSA bounce and suggests an inflammatory etiology. In the situation of a rising PSA, observation of focal activity on MRI/3D-MRSI could be a useful adjunct to suggest local recurrence at an earlier interval after brachytherapy when prostate biopsies would still be unhelpful. Longer follow-up is necessary to confirm the complex relationship between metabolic activity and PSA levels.

  6. Whole-Pelvis Radiotherapy in Combination With Interstitial Brachytherapy: Does Coverage of the Pelvic Lymph Nodes Improve Treatment Outcome in High-Risk Prostate Cancer?

    SciTech Connect

    Bittner, Nathan; Wallner, Kent E.; Butler, Wayne M.; Galbreath, Robert; Adamovich, Edward

    2010-03-15

    Purpose: To compare biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) rates among high-risk prostate cancer patients treated with brachytherapy and supplemental external beam radiation (EBRT) using either a mini-pelvis (MP) or a whole-pelvis (WP) field. Methods and Materials: From May 1995 to October 2005, 186 high-risk prostate cancer patients were treated with brachytherapy and EBRT with or without androgen-deprivation therapy (ADT). High-risk prostate cancer was defined as a Gleason score of >=8 and/or a prostate-specific antigen (PSA) concentration of >=20 ng/ml. Results: With a median follow-up of 6.7 years, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 91.7% vs. 84.4% (p = 0.126), 95.5% vs. 92.6% (p = 0.515), and 79.5% vs. 67.1% (p = 0.721), respectively. Among those patients who received ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 93.6% vs. 90.1% (p = 0.413), 94.2% vs. 96.0% (p = 0.927), and 73.7% vs. 70.2% (p = 0.030), respectively. Among those patients who did not receive ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 82.4% vs. 75.0% (p = 0.639), 100% vs. 88% (p = 0.198), and 87.5% vs. 58.8% (p = 0.030), respectively. Based on multivariate analysis, none of the evaluated parameters predicted for CSS, while bPFS was best predicted by ADT and percent positive biopsy results. OS was best predicted by age and percent positive biopsy results. Conclusions: For high-risk prostate cancer patients receiving brachytherapy, there is a nonsignificant trend toward improved bPFS, CSS, and OS rates when brachytherapy is given with WPRT. This trend is most apparent among ADT-naive patients, for whom a significant improvement in OS was observed.

  7. Long-Term Endoscopic Follow-Up of Patients with Chronic Radiation Proctopathy after Brachytherapy for Prostate Cancer

    PubMed Central

    Ohtani, Masahiro; Suto, Hiroyuki; Nosaka, Takuto; Saito, Yasushi; Ozaki, Yoshihiko; Hayama, Ryoko; Naito, Tatsushi; Takahashi, Kazuto; Ofuji, Kazuya; Matsuda, Hidetaka; Hiramatsu, Katsushi; Nemoto, Tomoyuki; Shioura, Hiroki; Kimura, Hirohiko; Aoki, Yoshitaka; Yokoyama, Osamu; Nakamoto, Yasunari

    2016-01-01

    Background. Chronic radiation proctopathy (CRP) is late toxicity and associated with morbidity. Aim. To investigate the predictors of prognosis in patients with CRP after brachytherapy (BT). Methods. One hundred four patients with prostate cancer were treated with BT or BT followed by external-beam radiotherapy (BT + EBRT). We retrospectively investigated the 5-year incidence of rectal bleeding and endoscopic findings of CRP using the Vienna Rectoscopy Score (VRS). Twenty patients with VRS ≥ 1 were divided into the improved VRS group without treatment, unchanged VRS group, and treated group. The parameters associated with alteration of VRS were analyzed. Results. The incidence of rectal bleeding was 24%. The risk of rectal bleeding was higher in patients treated with BT + EBRT compared to those treated with BT (p < 0.0001). The incidence of superficial microulceration was higher in the improved VRS group than in the unchanged VRS group (p < 0.05). The incidence of multiple confluent telangiectasia or superficial ulcers > 1 cm2 was higher in the treated group than in both the improved and unchanged VRS groups (p < 0.05). Conclusions. Patients treated with BT + EBRT have a high risk of CRP. Endoscopic findings were useful for prognostic prediction of CRP. PMID:27378828

  8. Toward adaptive stereotactic robotic brachytherapy for prostate cancer: Demonstration of an adaptive workflow incorporating inverse planning and an MR stealth robot

    PubMed Central

    CUNHA, J. ADAM; HSU, I-CHOW; POULIOT, JEAN; ROACH, MACK; SHINOHARA, KATSUTO; KURHANEWICZ, JOHN; REED, GALEN; STOIANOVICI, DAN

    2011-01-01

    To translate any robot into a clinical environment, it is critical that the robot can seamlessly integrate with all the technology of a modern clinic. MRBot, an MR-stealth brachytherapy delivery device, was used in a closed-bore 3T MRI and a clinical brachytherapy cone beam CT suite. Targets included ceramic dummy seeds, MR-Spectroscopy-sensitive metabolite, and a prostate phantom. Acquired DICOM images were exported to planning software to register the robot coordinates in the imager’s frame, contour and verify target locations, create dose plans, and export needle and seed positions to the robot. The coordination of each system element (imaging device, brachytherapy planning system, robot control, robot) was validated with a seed delivery accuracy of within 2 mm in both a phantom and soft tissue. An adaptive workflow was demonstrated by acquiring images after needle insertion and prior to seed deposition. This allows for adjustment if the needle is in the wrong position. Inverse planning (IPSA) was used to generate a seed placement plan and coordinates for ten needles and 29 seeds were transferred to the robot. After every two needles placed, an image was acquired. The placed seeds were identified and validated prior to placing the seeds in the next two needles. The ability to robotically deliver seeds to locations determined by IPSA and the ability of the system to incorporate novel needle patterns were demonstrated. Shown here is the ability to overcome this critical step. An adaptive brachytherapy workflow is demonstrated which integrates a clinical anatomy-based seed location optimization engine and a robotic brachytherapy device. Demonstration of this workflow is a key element of a successful translation to the clinic of the MRI stealth robotic delivery system, MRBot. PMID:20642386

  9. Toward adaptive stereotactic robotic brachytherapy for prostate cancer: demonstration of an adaptive workflow incorporating inverse planning and an MR stealth robot.

    PubMed

    Cunha, J Adam; Hsu, I-Chow; Pouliot, Jean; Roach Iii, Mack; Shinohara, Katsuto; Kurhanewicz, John; Reed, Galen; Stoianovici, Dan

    2010-08-01

    To translate any robot into a clinical environment, it is critical that the robot can seamlessly integrate with all the technology of a modern clinic. MRBot, an MR-stealth brachytherapy delivery device, was used in a closed-bore 3T MRI and a clinical brachytherapy cone beam CT suite. Targets included ceramic dummy seeds, MR-Spectroscopy-sensitive metabolite, and a prostate phantom. Acquired DICOM images were exported to planning software to register the robot coordinates in the imager's frame, contour and verify target locations, create dose plans, and export needle and seed positions to the robot. The coordination of each system element (imaging device, brachytherapy planning system, robot control, robot) was validated with a seed delivery accuracy of within 2 mm in both a phantom and soft tissue. An adaptive workflow was demonstrated by acquiring images after needle insertion and prior to seed deposition. This allows for adjustment if the needle is in the wrong position. Inverse planning (IPSA) was used to generate a seed placement plan and coordinates for ten needles and 29 seeds were transferred to the robot. After every two needles placed, an image was acquired. The placed seeds were identified and validated prior to placing the seeds in the next two needles. The ability to robotically deliver seeds to locations determined by IPSA and the ability of the system to incorporate novel needle patterns were demonstrated. Shown here is the ability to overcome this critical step. An adaptive brachytherapy workflow is demonstrated which integrates a clinical anatomy-based seed location optimization engine and a robotic brachytherapy device. Demonstration of this workflow is a key element of a successful translation to the clinic of the MRI stealth robotic delivery system, MRBot.

  10. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients

    SciTech Connect

    Butler, Wayne M.; Stewart, Renee R.; Merrick, Gregory S.

    2009-03-15

    the harmonic mean and expressions of the generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  11. A Phase II Study of High-Dose-Rate Afterloading Brachytherapy as Monotherapy for the Treatment of Localized Prostate Cancer

    SciTech Connect

    Corner, Carie Rojas, Ana Maria; Bryant, Linda; Ostler, Peter; Hoskin, Peter

    2008-10-01

    Purpose: A Phase II dose escalation study has been undertaken to evaluate high-dose-rate brachytherapy (HDRBT) monotherapy for prostate cancer. Methods and Materials: A total of 110 patients have been entered, all with locally advanced cancer. Three dose levels have been used; 34 Gy in four fractions, 36 Gy in four fractions, and 31.5 Gy in three fractions. These equate to 226Gy{sub 1.5}, 252Gy{sub 1.5}, and 252Gy{sub 1.5}, respectively. Thirty patients have received 34 Gy, 25 received 36 Gy, and 55 patients received 31.5 Gy. Acute and late toxicity was analyzed using the International Prostate Symptom Score, and urologic and rectal events were scored using the Radiation Therapy Oncology Group/Common Terminology Criteria scoring systems. Results: Seven patients required urethral catheterization at 2 weeks; 3 receiving 34 Gy, 1 receiving 36 Gy, and 3 receiving 31.5 Gy. Only 3 patients remained catheterized at 12 weeks. Radiation Therapy Oncology Group 1 and 2 gastrointestinal toxicity at 2 weeks was seen in 61%, 68%, and 77%, respectively. Grade 3 bladder toxicity was seen in 2 patients at 6 months, 1 each from the 36 Gy and 31.5 Gy arms. One patient from the 31.5-Gy cohort reported Grade 2 bowel toxicity at 6 months. Prostate-specific antigen (PSA), stratified for androgen deprivation therapy (ADT) and no-ADT patients ranged from 16.1-22.9 {mu}g/L and 11.1-12.5 {mu}g/L, respectively. This fell at 12 months to 0.2-0.6 {mu}g/L and 0.5-1.4 {mu}g/L, respectively. No PSA relapses have yet been seen with a median follow-up of 30 months (34 Gy), 18 months (36 Gy), and 11.8 months (31.5 Gy). Conclusions: Early results suggest an excellent biochemical response with no differences seen in acute and late toxicity between doses of 34 Gy/four fractions, 36 Gy/four fractions, or 31.5 Gy/three fractions.

  12. High-Dose-Rate Brachytherapy of a Single Implant With Two Fractions Combined With External Beam Radiotherapy for Hormone-Naive Prostate Cancer

    SciTech Connect

    Sato, Morio Mori, Takashi; Shirai, Shintaro; Kishi, Kazushi; Inagaki, Takeshi; Hara, Isao

    2008-11-15

    Purpose: To evaluate the preliminary outcomes of high-dose-rate (HDR) brachytherapy of a single implant with two fractions and external beam radiotherapy (EBRT) for hormone-naive prostate cancer. Methods and Materials: Between March 2000 and Sept 2003, a total of 53 patients with tumor Stage T1c-T3b N0 M0 prostate cancer were treated with HDR brachytherapy boost doses (7.5 Gy/fraction) and 50-Gy EBRT during a 5.5-week period. Median follow-up was 61 months. Patients were divided into groups with localized (T1c-T2b) and advanced disease (T3a-T3b). We used the American Society for Therapeutic Radiology and Oncology (ASTRO) definition for biochemical failure. According to recommendations of the Radiation Therapy Oncology Group-ASTRO Phoenix Consensus Conference, biochemical failure-free control rates (BF-FCRs) at 3 years were investigated as 2 years short of the median follow-up. Results: Between April 2000 and Sept 2007, Common Terminology Criteria for Adverse Events Version 2.0 late Grade 2 genitourinary and gastrointestinal toxicity rates were 0% and 3.8%, respectively. Erectile preservation was 25% at 5 years. Overall survival was 88.1% and cause-specific survival was 100%. At 3 years, ASTRO BF-FCRs of the localized and advanced groups were 100% and 42%, respectively (p = 0.001). Conclusions: The HDR brachytherapy of a single implant with two fractions plus EBRT is effective in treating patients with localized hormone-naive prostate cancer, with the least genitourinary and gastrointestinal toxicities; however, longer median BF-FCR follow-up is required to assess these findings.

  13. Second malignancies after prostate brachytherapy: Incidence of bladder and colorectal cancers in patients with 15 years of potential follow-up

    SciTech Connect

    Liauw, Stanley L.; Sylvester, John E. . E-mail: johnsylvester@seattleprostateinst.com; Morris, Christopher G.; Blasko, John C.; Grimm, Peter D.

    2006-11-01

    Purpose: To report the incidence of second bladder and colorectal cancers after prostate brachytherapy. Methods and Materials: This review included 125 patients treated with I-125 brachytherapy alone, and 223 patients who received supplemental external beam radiation therapy. Median follow-up was 10.5 years. Patients were followed for the development of lower genitourinary and colorectal cancers. Second malignancies arising five years after radiation therapy were defined as being potentially associated with treatment; observed rates were then compared with age-matched expected rates according to Surveillance, Epidemiology, and End Results data. Results: Five years out of treatment, there were 15 patients with a second solid tumor, including bladder cancer (n = 11), colorectal cancer (n = 3), and prostatic urethra cancer (n = 1). The incidence of second malignancy was no different in patients treated with brachytherapy alone (1.6%) vs. those receiving external beam radiotherapy (5.8%, p = 0.0623). There were more observed bladder cancers compared with those expected (relative risk, 2.34, 95% confidence interval 0.96-3.72; absolute excess risk 35 cancers per 10,000 patients). Relative risk did not significantly change over increasing follow-up intervals up to 20 years after treatment. Conclusions: There may be an increased but small risk of developing a second malignancy after radiation therapy for prostate cancer. This outcome could be related to radiation carcinogenesis, but more vigilant screening and thorough workup as a result of radiation side effects and predisposing conditions (e.g., genetic and environmental factors) in many of the patients found to have second malignancies likely contributed to the higher number of observed malignancies than expected.

  14. Analysis of high–dose rate brachytherapy dose distribution resemblance in CyberKnife hypofractionated treatment plans of localized prostate cancer

    SciTech Connect

    Sudahar, H.; Kurup, P.G.G.; Murali, V.; Mahadev, P.; Velmurugan, J.

    2013-01-01

    The present study is to analyze the CyberKnife hypofractionated dose distribution of localized prostate cancer in terms of high–dose rate (HDR) brachytherapy equivalent doses to assess the degree of HDR brachytherapy resemblance of CyberKnife dose distribution. Thirteen randomly selected localized prostate cancer cases treated using CyberKnife with a dose regimen of 36.25 Gy in 5 fractions were considered. HDR equivalent doses were calculated for 30 Gy in 3 fractions of HDR brachytherapy regimen. The D{sub 5%} of the target in the CyberKnife hypofractionation was 41.57 ± 2.41 Gy. The corresponding HDR fractionation (3 fractions) equivalent dose was 32.81 ± 1.86 Gy. The mean HDR fractionation equivalent dose, D{sub 98%}, was 27.93 ± 0.84 Gy. The V{sub 100%} of the prostate target was 95.57% ± 3.47%. The V{sub 100%} of the bladder and the rectum were 717.16 and 79.6 mm{sup 3}, respectively. Analysis of the HDR equivalent dose of CyberKnife dose distribution indicates a comparable resemblance to HDR dose distribution in the peripheral target doses (D{sub 98%} to D{sub 80%}) reported in the literature. However, there is a substantial difference observed in the core high-dose regions especially in D{sub 10%} and D{sub 5%}. The dose fall-off within the OAR is also superior in reported HDR dose distribution than the HDR equivalent doses of CyberKnife.

  15. High-dose-rate prostate brachytherapy inverse planning on dose-volume criteria by simulated annealing

    NASA Astrophysics Data System (ADS)

    Deist, T. M.; Gorissen, B. L.

    2016-02-01

    High-dose-rate brachytherapy is a tumor treatment method where a highly radioactive source is brought in close proximity to the tumor. In this paper we develop a simulated annealing algorithm to optimize the dwell times at preselected dwell positions to maximize tumor coverage under dose-volume constraints on the organs at risk. Compared to existing algorithms, our algorithm has advantages in terms of speed and objective value and does not require an expensive general purpose solver. Its success mainly depends on exploiting the efficiency of matrix multiplication and a careful selection of the neighboring states. In this paper we outline its details and make an in-depth comparison with existing methods using real patient data.

  16. High-dose-rate prostate brachytherapy inverse planning on dose-volume criteria by simulated annealing.

    PubMed

    Deist, T M; Gorissen, B L

    2016-02-01

    High-dose-rate brachytherapy is a tumor treatment method where a highly radioactive source is brought in close proximity to the tumor. In this paper we develop a simulated annealing algorithm to optimize the dwell times at preselected dwell positions to maximize tumor coverage under dose-volume constraints on the organs at risk. Compared to existing algorithms, our algorithm has advantages in terms of speed and objective value and does not require an expensive general purpose solver. Its success mainly depends on exploiting the efficiency of matrix multiplication and a careful selection of the neighboring states. In this paper we outline its details and make an in-depth comparison with existing methods using real patient data. PMID:26760757

  17. Androgen Deprivation Therapy Does Not Impact Cause-Specific or Overall Survival in High-Risk Prostate Cancer Managed With Brachytherapy and Supplemental External Beam

    SciTech Connect

    Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Allen, Zachariah A.; Adamovich, Edward; Lief, Jonathan

    2007-05-01

    Purpose: To determine cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in high-risk prostate cancer patients undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and July 2002, 204 patients with high-risk prostate cancer (Gleason score {>=}8 or prostate-specific antigen [PSA] >20 ng/mL or clinical stage {>=}T2c) underwent brachytherapy. Median follow-up was 7.0 years. The bPFS was defined by a PSA {<=}0.40 ng/mL after nadir. Multiple clinical, treatment, and dosimetric parameters were evaluated for the impact on survival. Results: The 10-year CSS, bPFS, and OS were 88.9%, 86.6%, and 68.6%, respectively. A statistically significant difference in bPFS was discerned between hormone naive, ADT {<=}6 months, and ADT >6 month cohorts (79.7% vs. 95.% vs. 89.9%, p = 0.032). Androgen deprivation therapy (ADT) did not impact CSS or OS. For bPFS patients, the median posttreatment PSA was <0.04 ng/mL. A Cox linear regression analysis demonstrated that Gleason score was the best predictor of CSS, whereas percent positive biopsies and duration of ADT best predicted for bPFS. The OS was best predicted by Gleason score and diabetes. Thirty-eight patients have died, with 26 of the deaths from cardiovascular/pulmonary disease or second malignancy. Eleven patients have died of metastatic prostate cancer. Conclusions: The ADT improved 10-year bPFS without statistical impact on CSS or OS. Death as a result of cardiovascular/pulmonary disease and second malignancies were more than twice as common as prostate cancer deaths. Strategies to improve cardiovascular health should positively impact OS.

  18. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: A pilot ex vivo study

    SciTech Connect

    Mehrmohammadi, Mohammad; Kinnick, Randall R.; Fatemi, Mostafa; Alizad, Azra; Davis, Brian J.

    2014-09-15

    Purpose: Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. Methods: Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. Results: The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%–92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. Conclusions: Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that

  19. Simulation and experiment of soft-tissue deformation in prostate brachytherapy.

    PubMed

    Liang, Dong; Jiang, Shan; Yang, Zhiyong; Wang, Xingji

    2016-06-01

    Soft-tissue deformation is one of the major reasons for the inaccurate positioning of percutaneous needle insertion process. In this article, simulations and experiments of the needle insertion soft-tissue process are both applied to study soft-tissue deformation. A needle deflection model based on the mechanics is used to calculate the needle deflection during the interaction process. The obtained needle deflection data are applied into finite element analysis process as the system input. The uniaxial tensile strength tests, compression tests, and static indentation experiments are used to obtain the soft-tissue parameters and choose the best strain-energy function to model in the simulation. Magnetic resonance imaging is used to reconstruct the prostate, establishing both prostate three-dimensional finite element model and artificial prostate model. The needle-soft tissue interaction simulation results are compared with those of the needle insertion experiment. The displacement data of the mark point in the experiment are comparable to the simulation results. It is concluded that, using this simulation method, the surgeon can predict the deformation of the tissue and the displacement of the target in advance. PMID:27129384

  20. CT, MR, and ultrasound image artifacts from prostate brachytherapy seed implants: The impact of seed size

    SciTech Connect

    Robertson, Andrew K. H.; Basran, Parminder S.; Thomas, Steven D.; Wells, Derek

    2012-04-15

    Purpose: To investigate the effects of brachytherapy seed size on the quality of x-ray computed tomography (CT), ultrasound (US), and magnetic resonance (MR) images and seed localization through comparison of the 6711 and 9011 {sup 125}I sources. Methods: For CT images, an acrylic phantom mimicking a clinical implantation plan and embedded with low contrast regions of interest (ROIs) was designed for both the 0.774 mm diameter 6711 (standard) and the 0.508 mm diameter 9011 (thin) seed models (Oncura, Inc., and GE Healthcare, Arlington Heights, IL). Image quality metrics were assessed using the standard deviation of ROIs between the seeds and the contrast to noise ratio (CNR) within the low contrast ROIs. For US images, water phantoms with both single and multiseed arrangements were constructed for both seed sizes. For MR images, both seeds were implanted into a porcine gel and imaged with pelvic imaging protocols. The standard deviation of ROIs and CNR values were used as metrics of artifact quantification. Seed localization within the CT images was assessed using the automated seed finder in a commercial brachytherapy treatment planning system. The number of erroneous seed placements and the average and maximum error in seed placements were recorded as metrics of the localization accuracy. Results: With the thin seeds, CT image noise was reduced from 48.5 {+-} 0.2 to 32.0 {+-} 0.2 HU and CNR improved by a median value of 74% when compared with the standard seeds. Ultrasound image noise was measured at 50.3 {+-} 17.1 dB for the thin seed images and 50.0 {+-} 19.8 dB for the standard seed images, and artifacts directly behind the seeds were smaller and less prominent with the thin seed model. For MR images, CNR of the standard seeds reduced on average 17% when using the thin seeds for all different imaging sequences and seed orientations, but these differences are not appreciable. Automated seed localization required an average ({+-}SD) of 7.0 {+-} 3.5 manual

  1. Clinical implementation of a digital tomosynthesis-based seed reconstruction algorithm for intraoperative postimplant dose evaluation in low dose rate prostate brachytherapy

    SciTech Connect

    Brunet-Benkhoucha, Malik; Verhaegen, Frank; Lassalle, Stephanie; Beliveau-Nadeau, Dominic; Reniers, Brigitte; Donath, David; Taussky, Daniel; Carrier, Jean-Francois

    2009-11-15

    Purpose: The low dose rate brachytherapy procedure would benefit from an intraoperative postimplant dosimetry verification technique to identify possible suboptimal dose coverage and suggest a potential reimplantation. The main objective of this project is to develop an efficient, operator-free, intraoperative seed detection technique using the imaging modalities available in a low dose rate brachytherapy treatment room. Methods: This intraoperative detection allows a complete dosimetry calculation that can be performed right after an I-125 prostate seed implantation, while the patient is still under anesthesia. To accomplish this, a digital tomosynthesis-based algorithm was developed. This automatic filtered reconstruction of the 3D volume requires seven projections acquired over a total angle of 60 deg. with an isocentric imaging system. Results: A phantom study was performed to validate the technique that was used in a retrospective clinical study involving 23 patients. In the patient study, the automatic tomosynthesis-based reconstruction yielded seed detection rates of 96.7% and 2.6% false positives. The seed localization error obtained with a phantom study is 0.4{+-}0.4 mm. The average time needed for reconstruction is below 1 min. The reconstruction algorithm also provides the seed orientation with an uncertainty of 10 deg. {+-}8 deg. The seed detection algorithm presented here is reliable and was efficiently used in the clinic. Conclusions: When combined with an appropriate coregistration technique to identify the organs in the seed coordinate system, this algorithm will offer new possibilities for a next generation of clinical brachytherapy systems.

  2. Iodine-125 irradiation inhibits invasion of gastric cancer cells by reactivating microRNA-181c expression

    PubMed Central

    Yang, Yong; Ma, Zhen-Huan; Li, Xiao-Gang; Zhang, Wan-Fu; Wan, Jia; Du, Ling-Juan; Li, Guo-Jian; Yang, Guo-Kai; Lu, Ping

    2016-01-01

    Iodine-125 (125I) seed implantation has been widely used for the treatment of unresectable advanced tumors. However, the molecular mechanisms underlying the tumor-suppressive effects of 125I irradiation have not been fully elucidated. The present study demonstrated that 125I irradiation suppresses cell viability and inhibits cell invasiveness of gastric cancer KATO-III and MKN45 cells. Further mechanistic analysis suggested the involvement of microRNA (miR)-181c in the inhibitory effects induced by 125I irradiation. Methylated DNA immunoprecipitation coupled with quantitative-polymerase chain reaction demonstrated that treatment with 125I irradiation, at the dose of 4 Gy, induced promoter demethylation of the miR-181c gene in KATO-III and MKN45 cells. Following irradiation, the expression of miR-181c was significantly increased, which may be attributed to the demethylation caused by 125I irradiation. In addition, upregulation of miR-181c by administration of miR-181c mimics decreased cell invasion, suggesting the role of miR-181c as a tumor suppressor. More importantly, the tumor-suppressive effects of 125I irradiation were significantly compromised by the introduction of miR-181c inhibitors. Overall, these results reveal that 125I irradiation inhibits invasiveness of gastric cancer cells by reactivating miR-181c at the epigenetic level, thereby providing important molecular evidence for the anticancer effects of 125I irradiation. PMID:27698859

  3. Iodine-125 irradiation inhibits invasion of gastric cancer cells by reactivating microRNA-181c expression

    PubMed Central

    Yang, Yong; Ma, Zhen-Huan; Li, Xiao-Gang; Zhang, Wan-Fu; Wan, Jia; Du, Ling-Juan; Li, Guo-Jian; Yang, Guo-Kai; Lu, Ping

    2016-01-01

    Iodine-125 (125I) seed implantation has been widely used for the treatment of unresectable advanced tumors. However, the molecular mechanisms underlying the tumor-suppressive effects of 125I irradiation have not been fully elucidated. The present study demonstrated that 125I irradiation suppresses cell viability and inhibits cell invasiveness of gastric cancer KATO-III and MKN45 cells. Further mechanistic analysis suggested the involvement of microRNA (miR)-181c in the inhibitory effects induced by 125I irradiation. Methylated DNA immunoprecipitation coupled with quantitative-polymerase chain reaction demonstrated that treatment with 125I irradiation, at the dose of 4 Gy, induced promoter demethylation of the miR-181c gene in KATO-III and MKN45 cells. Following irradiation, the expression of miR-181c was significantly increased, which may be attributed to the demethylation caused by 125I irradiation. In addition, upregulation of miR-181c by administration of miR-181c mimics decreased cell invasion, suggesting the role of miR-181c as a tumor suppressor. More importantly, the tumor-suppressive effects of 125I irradiation were significantly compromised by the introduction of miR-181c inhibitors. Overall, these results reveal that 125I irradiation inhibits invasiveness of gastric cancer cells by reactivating miR-181c at the epigenetic level, thereby providing important molecular evidence for the anticancer effects of 125I irradiation.

  4. SU-E-J-215: Towards MR-Only Image Guided Identification of Calcifications and Brachytherapy Seeds: Application to Prostate and Breast LDR Implant Dosimetry

    SciTech Connect

    Elzibak, A; Fatemi-Ardekani, A; Soliman, A; Mashouf, S; Safigholi, H; Ravi, A; Morton, G; Song, WY; Han, D

    2015-06-15

    Purpose: To identify and analyze the appearance of calcifications and brachytherapy seeds on magnitude and phase MRI images and to investigate whether they can be distinguished from each other on corrected phase images for application to prostate and breast low dose rate (LDR) implant dosimetry. Methods: An agar-based gel phantom containing two LDR brachytherapy seeds (Advantage Pd-103, IsoAid, 0.8mm diameter, 4.5mm length) and two spherical calcifications (large: 7mm diameter and small: 4mm diameter) was constructed and imaged on a 3T Philips MR scanner using a 16-channel head coil and a susceptibility weighted imaging (SWI) sequence (2mm slices, 320mm FOV, TR/ TE= 26.5/5.3ms, 15 degree flip angle). The phase images were unwrapped and corrected using a 32×32, 2D Hanning high pass filter to remove background phase noise. Appearance of the seeds and calcifications was assessed visually and quantitatively using Osirix (http://www.osirix-viewer.com/). Results: As expected, calcifications and brachytherapy seeds appeared dark (hypointense) relative to the surrounding gel on the magnitude MRI images. The diameter of each seed without the surrounding artifact was measured to be 0.1 cm on the magnitude image, while diameters of 0.79 and 0.37 cm were measured for the larger and smaller calcifications, respectively. On the corrected phase images, the brachytherapy seeds and the calcifications appeared bright (hyperintense). The diameter of the seeds was larger on the phase images (0.17 cm) likely due to the dipole effect. Conclusion: MRI has the best soft tissue contrast for accurate organ delineation leading to most accurate implant dosimetry. This work demonstrated that phase images can potentially be useful in identifying brachytherapy seeds and calcifications in the prostate and breast due to their bright appearance, which helps in their visualization and quantification for accurate dosimetry using MR-only. Future work includes optimizing phase filters to best identify

  5. Automated localization of implanted seeds in 3D TRUS images used for prostate brachytherapy

    SciTech Connect

    Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2006-07-15

    An algorithm has been developed in this paper to localize implanted radioactive seeds in 3D ultrasound images for a dynamic intraoperative brachytherapy procedure. Segmentation of the seeds is difficult, due to their small size in relatively low quality of transrectal ultrasound (TRUS) images. In this paper, intraoperative seed segmentation in 3D TRUS images is achieved by performing a subtraction of the image before the needle has been inserted, and the image after the seeds have been implanted. The seeds are searched in a 'local' space determined by the needle position and orientation information, which are obtained from a needle segmentation algorithm. To test this approach, 3D TRUS images of the agar and chicken tissue phantoms were obtained. Within these phantoms, dummy seeds were implanted. The seed locations determined by the seed segmentation algorithm were compared with those obtained from a volumetric cone-beam flat-panel micro-CT scanner and human observers. Evaluation of the algorithm showed that the rms error in determining the seed locations using the seed segmentation algorithm was 0.98 mm in agar phantoms and 1.02 mm in chicken phantoms.

  6. Characterization of the susceptibility artifact around a prostate brachytherapy seed in MRI

    SciTech Connect

    Wachowicz, K.; Thomas, S. D.; Fallone, B. G.

    2006-12-15

    Magnetic distortions surrounding a typical brachytherapy seed (IMC6711, OncoSeed{sup TM}) within a clinical magnetic resonance imager were modeled for a number of different seed orientations with respect to the main magnetic field. From these distortion maps, simulated images were produced. The simulated images were then compared to images experimentally acquired using a spin echo technique on a Philips 1.5 T magnetic resonance imaging scanner. The modeled images were found to conform very well to those acquired experimentally, thus allowing one to establish where the seed is positioned within the complex image distortion patterns. The artifact patterns were dependent on the orientation of the seed with the main magnetic field, as well as the direction of the read encode gradient. While all imaging schemes which employ a unidirectional linear read encode trajectory should produce the artifacts modeled in this article, sequences other than spin echo may produce additional artifacts. Gradient echo and steady-state free precession imaging techniques were also performed on the seed for comparison.

  7. Evaluation of Dosimetric Parameters and Disease Response After {sup 125}Iodine Transperineal Brachytherapy for Low- and Intermediate-Risk Prostate Cancer

    SciTech Connect

    Morris, W. James Keyes, Mira M.D.; Palma, David M.D.; McKenzie, Michael; Spadinger, Ingrid; Agranovich, Alex; Pickles, Tom; Liu, Mitchell; Kwan, Winkle; Wu, Jonn; Lapointe, Vince; Berthelet, Eric; Pai, Howard; Harrison, Robert; Kwa, William; Bucci, Joe; Racz, Violet; Woods, Ryan

    2009-04-01

    Purpose: To analyze dosimetric outcomes after permanent brachytherapy for men with low-risk and 'low-tier' intermediate-risk prostate cancer and explore the relationship between the traditional dosimetric values, V100 (volume of prostate receiving 100% of the prescribed dose) and D90 (minimum dose to 90% of the prostate), and risk of biochemical failure. Methods and Materials: A total of 1,006 consecutive patients underwent implantation between July 20, 1998, and Oct 23, 2003. Most (58%) had low-risk disease; the remaining 42% comprised a selected low-tier subgroup of intermediate-risk patients. The prescribed minimum peripheral dose (MPD) was 144 Gy. All implants used 0.33 mCi {sup 125}I sources using a preplan technique featuring right-left symmetry and a strong posterior-peripheral dose bias. Sixty-five percent of patients had 6 months of androgen deprivation therapy. Postimplantation dosimetry was calculated using day-28 CT scans. Results: With a median follow-up of 54 months, the actuarial 5-year rate of freedom from biochemical recurrence (bNED) was 95.6% {+-} 1.6%. Median D90 was 105% of MPD, median V100 was 92%, median V150 was 58%, and median V200 was 9%. Dosimetric values were not predictive of biochemical recurrence on univariate or multivariate analysis. Analysis of dosimetric values by implantation number showed statistically significant increases in all values with time (D90, V100, V150, and V200; p < 0.001), but this did not translate into improved bNED. Conclusions: In contrast to some previous studies, dosimetric outcomes did not correlate with biochemical recurrence in the first 1,006 patients treated with {sup 125}I prostate brachytherapy at the British Columbia Cancer Agency. Despite a median D90 of only 105% of MPD, our bNED rates are indistinguishable from series that reported higher D90 values.

  8. Monte Carlo simulation of a realistic anatomical phantom described by triangle meshes: application to prostate brachytherapy imaging

    PubMed Central

    Badal, Andreu; Kyprianou, Iacovos; Badano, Aldo; Sempau, Josep

    2008-01-01

    Purpose Monte Carlo codes can simulate the transport of radiation within matter with high accuracy and can be used to study medical applications of ionising radiations. The aim of our work was to develop a Monte Carlo code capable of generating projection images of the human body. In order to obtain clinically realistic images a detailed anthropomorphic phantom was prepared. These two simulation tools are intended to study the multiple applications of imaging in radiotherapy, from image guided treatments to portal imaging. Methods We adapted the general purpose code PENELOPE 2006 to simulate a radiation source, an ideal digital detector, and a realistic model of the patient anatomy. The anthropomorphic phantom was developed using computer-aided design tools, and is based on the NCAT phantom. The surface of each organ is modelled using a closed triangle mesh, and the full phantom contains 330 organs and more than 5 million triangles. A novel object-oriented geometry package, which includes an octree structure to sort the triangles, has been developed to use this complex geometry with PENELOPE. Results As an example of the capabilities of the new code, projection images of the human pelvis region were simulated. Radioactive seeds were included inside the phantom’s prostate. Therefore, the resulting simulated images resemble what would be obtained in a clinical procedure to assess the positioning of the seeds in a prostate brachytherapy treatment. Conclusions The new code can produce projection images of the human body that are comparable to those obtained by a real imaging system (within the limitations of the anatomical phantom and the detector model). The simulated images can be used to study and optimise an imaging task (i.e., maximise the object detectability, minimise the delivered dose, find the optimum beam energy, etc.). Since PENELOPE can simulate radiation from 50 eV to 1 GeV, the code can also be used to simulate radiotherapy treatments and portal

  9. There Is No Correlation Between Erectile Dysfunction and Dose to Penile Bulb and Neurovascular Bundles Following Real-Time Low-Dose-Rate Prostate Brachytherapy

    SciTech Connect

    Solan, Amy N. Cesaretti, Jamie A.; Stone, Nelson N.; Stock, Richard G.

    2009-04-01

    Purpose: We evaluated the relationship between the onset of erectile dysfunction and dose to the penile bulb and neurovascular bundles (NVBs) after real-time ultrasound-guided prostate brachytherapy. Methods and Materials: One hundred forty-seven patients who underwent prostate brachytherapy met the following eligibility criteria: (1) treatment with {sup 125}I brachytherapy to a prescribed dose of 160 Gy with or without hormones without supplemental external beam radiation therapy, (2) identification as potent before the time of implantation based on a score of 2 or higher on the physician-assigned Mount Sinai Erectile Function Score and a score of 16 or higher on the abbreviated International Index of Erectile Function patient assessment, and (3) minimum follow-up of 12 months. Median follow-up was 25.7 months (range, 12-47 months). Results: The 3-year actuarial rate of impotence was 23% (34 of 147 patients). An additional 43% of potent patients (49 of 113 patients) were using a potency aid at last follow-up. The penile bulb volume receiving 100% of the prescription dose (V{sub 100}) ranged from 0-0.05 cc (median, 0 cc), with a dose to the hottest 5% (D{sub 5}) range of 12.5-97.9 Gy (median, 40.8 Gy). There was no correlation between penile bulb D{sub 5} or V{sub 100} and postimplantation impotency on actuarial analysis. For the combined right and left NVB structures, V{sub 100} range was 0.3-5.1 cc (median, 1.8 cc), and V{sub 150} range was 0-1.5 cc (median, 0.31 cc). There was no association between NVB V{sub 100} or V{sub 150} and postimplantation impotency on actuarial analysis. Conclusion: Penile bulb doses are low after real-time ultrasound-guided prostate brachytherapy. We found no correlation between dose to either the penile bulb or NVBs and the development of postimplantation impotency.

  10. Timing of High-Dose Rate Brachytherapy With External Beam Radiotherapy in Intermediate and High-Risk Localized Prostate CAncer (THEPCA) Patients and Its Effects on Toxicity and Quality of Life: Protocol of a Randomized Feasibility Trial

    PubMed Central

    Palvai, Sreekanth; Harrison, Michael; Shibu Thomas, Sharon; Hayden, Karen; Green, James; Anderson, Oliver; Romero, Lavinia; Lodge, Richard; Burns, Patricia

    2015-01-01

    Background Prostate cancer is the most common cancer in males in the UK and affects around 105 men for every 100,000. The role of radiotherapy in the management of prostate cancer significantly changed over the last few decades with developments in brachytherapy, external beam radiotherapy (EBRT), intensity-modulated radiotherapy (IMRT), and image-guided radiotherapy (IGRT). One of the challenging factors of radiotherapy treatment of localized prostate cancer is the development of acute and late genitourinary and gastrointestinal toxicities. The recent European guidelines suggest that there is no consensus regarding the timing of high-dose rate (HDR) brachytherapy and EBRT. The schedules vary in different institutions where an HDR boost can be given either before or after EBRT. Few centers deliver HDR in between the fractions of EBRT. Objective Assessment of acute genitourinary and gastrointestinal toxicities at various time points to better understand if the order in which treatment modality is delivered (ie, HDR brachytherapy or EBRT first) has an effect on the toxicity profile. Methods Timing of HDR brachytherapy with EBRT in Prostate CAncer (THEPCA) is a single-center, open, randomized controlled feasibility trial in patients with intermediate and high-risk localized prostate cancer. A group of 50 patients aged 18 years old and over with histological diagnosis of prostate cancer (stages T1b-T3BNOMO), will be randomized to one of two treatment arms (ratio 1:1), following explanation of the study and informed consent. Patients in both arms of the study will be treated with HDR brachytherapy and EBRT, however, the order in which they receive the treatments will vary. In Arm A, patients will receive HDR brachytherapy before EBRT. In Arm B (control arm), patients will receive EBRT before HDR brachytherapy. Study outcomes will look at prospective assessment of genitourinary and gastrointestinal toxicities. The primary endpoint will be grade 3 genitourinary toxicity

  11. Selecting Patients for Exclusive Permanent Implant Prostate Brachytherapy: The Experience of the Paris Institut Curie/Cochin Hospital/Necker Hospital Group on 809 Patients

    SciTech Connect

    Cosset, Jean-Marc Flam, Thierry; Thiounn, Nicolas; Gomme, Stephanie; Rosenwald, Jean-Claude; Asselain, Bernard; Pontvert, Dominique; Henni, Mehdi; Debre, Bernard; Chauveinc, Laurent

    2008-07-15

    Purpose: The aim of this study was to analyze overall and relapse-free survival in a cohort of 809 patients, 34% of whom corresponded to a higher-risk group than American Brachytherapy Society (ABS) criteria. Methods and Materials: Between January 1999 and September 2004, 809 patients were treated with permanent loose 125 iodine seed implantation (IsoSeed Bebig, Eckert and Ziegler) by the Paris Institut Curie, Cochin Hospital, and Necker Hospital group. Of these 809 patients, 533 (65.9%) corresponded exactly to ABS criteria. Two hundred and seventy-six patients (34.1%) had a prostate-specific antigen (PSA) level between 10 and 15, or a Gleason score of 7, or both (non-ABS group). Results: Overall 5-year survival was 98%, with no difference between the ABS group and the non-ABS patient subgroups (p 0.62).Five-year relapse-free survival was 97% in the ABS group; it was significantly lower (p = 0.001) in the non-ABS group but remained satisfactory at 94%. On subgroup analysis, the results appeared to be better for the subgroup of patients with PSA 10-15 than for the subgroup with a Gleason score of 7. Conclusions: Our results suggest that selected patients in the intermediate-risk group of localized prostate cancers can be safely proposed as recipients of permanent implant brachytherapy as monotherapy.

  12. Radio-guided occult lesion localisation using iodine 125 Seeds “ROLLIS” to guide surgical removal of an impalpable posterior chest wall melanoma metastasis

    SciTech Connect

    Dissanayake, Shashini; Dissanayake, Deepthi; Taylor, Donna B

    2015-09-15

    Cancer screening and surveillance programmes and the use of sophisticated imaging tools such as positron emission tomography-computed tomography (PET-CT) have increased the detection of impalpable lesions requiring imaging guidance for excision. A new technique involves intra-lesional insertion of a low-activity iodine-125 ({sup 125}I) seed and detection of the radioactive signal in theatre using a hand-held gamma probe to guide surgery. Whilst several studies describe using this method to guide the removal of impalpable breast lesions, only a handful of publications report its use to guide excision of lesions outside the breast. We describe a case in which radio-guided occult lesion localisation using an iodine 125 seed was used to guide excision of an impalpable posterior chest wall metastasis detected on PET-CT.

  13. High-Risk Prostate Cancer With Gleason Score 8-10 and PSA Level {<=}15 ng/ mL Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Fang, L. Christine; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Murray, Brian C.; Reed, Joshua L.; Adamovich, Edward; Wallner, Kent E.

    2011-11-15

    Purpose: With widespread prostate-specific antigen (PSA) screening, there has been an increase in men diagnosed with high-risk prostate cancer defined by a Gleason score (GS) {>=}8 coupled with a relatively low PSA level. The optimal management of these patients has not been defined. Cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) were evaluated in brachytherapy patients with a GS {>=}8 and a PSA level {<=}15 ng/mL with or without androgen-deprivation therapy (ADT). Methods and Materials: From April 1995 to October 2005, 174 patients with GS {>=}8 and a PSA level {<=}15 ng/mL underwent permanent interstitial brachytherapy. Of the patients, 159 (91%) received supplemental external beam radiation, and 113 (64.9%) received ADT. The median follow-up was 6.6 years. The median postimplant Day 0 minimum percentage of the dose covering 90% of the target volume was 121.1% of prescription dose. Biochemical control was defined as a PSA level {<=}0.40 ng/mL after nadir. Multiple parameters were evaluated for impact on survival. Results: Ten-year outcomes for patients without and with ADT were 95.2% and 92.5%, respectively, for CSS (p = 0.562); 86.5% and 92.6%, respectively, for bPFS (p = 0.204); and 75.2% and 66.0%, respectively, for OS (p = 0.179). The median post-treatment PSA level for biochemically controlled patients was <0.02 ng/mL. Multivariate analysis failed to identify any predictors for CSS, whereas bPFS and OS were most closely related to patient age. Conclusions: Patients with GS {>=}8 and PSA level {<=}15 ng/mL have excellent bPFS and CSS after brachytherapy with supplemental external beam radiotherapy. The use of ADT did not significantly impact bPFS, CSS, or OS.

  14. Oblique needle segmentation and tracking for 3D TRUS guided prostate brachytherapy

    SciTech Connect

    Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2005-09-15

    An algorithm was developed in order to segment and track brachytherapy needles inserted along oblique trajectories. Three-dimensional (3D) transrectal ultrasound (TRUS) images of the rigid rod simulating the needle inserted into the tissue-mimicking agar and chicken breast phantoms were obtained to test the accuracy of the algorithm under ideal conditions. Because the robot possesses high positioning and angulation accuracies, we used the robot as a ''gold standard,'' and compared the results of algorithm segmentation to the values measured by the robot. Our testing results showed that the accuracy of the needle segmentation algorithm depends on the needle insertion distance into the 3D TRUS image and the angulations with respect to the TRUS transducer, e.g., at a 10 deg. insertion anglulation in agar phantoms, the error of the algorithm in determining the needle tip position was less than 1 mm when the insertion distance was greater than 15 mm. Near real-time needle tracking was achieved by scanning a small volume containing the needle. Our tests also showed that, the segmentation time was less than 60 ms, and the scanning time was less than 1.2 s, when the insertion distance into the 3D TRUS image was less than 55 mm. In our needle tracking tests in chicken breast phantoms, the errors in determining the needle orientation were less than 2 deg. in robot yaw and 0.7 deg. in robot pitch orientations, for up to 20 deg. needle insertion angles with the TRUS transducer in the horizontal plane when the needle insertion distance was greater than 15 mm.

  15. Intensity-Modulated Radiotherapy Causes Fewer Side Effects than Three-Dimensional Conformal Radiotherapy When Used in Combination With Brachytherapy for the Treatment of Prostate Cancer

    SciTech Connect

    Forsythe, Kevin; Blacksburg, Seth; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To measure the benefits of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3D-CRT) when used in combination with brachytherapy for the treatment of prostate cancer. Methods and Materials: We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of {sup 103}Pd or {sup 125}I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson {chi}{sup 2} test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors. Results: Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19% mild, 44% moderate, and 37% severe; patients treated with IMRT scored their urinary symptoms as follows: 36% mild, 47% moderate, and 17% severe (p < 0.001). The 3D-CRT patients rated their QOL as follows: 35% positive, 20% neutral, and 45% negative; IMRT patients rated their QOL as follows: 51% positive, 18% neutral, and 31% negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade {>=}2 rectal bleeding was reported by 11% of 3D

  16. BrachyView: Proof-of-principle of a novel in-body gamma camera for low dose-rate prostate brachytherapy

    SciTech Connect

    Petasecca, M.; Loo, K. J.; Safavi-Naeini, M.; Han, Z.; Metcalfe, P. E.; Lerch, M. L. F.; Qi, Y.; Rosenfeld, A. B.; Meikle, S.; Pospisil, S.; Jakubek, J.; Bucci, J. A.; Zaider, M.

    2013-04-15

    Purpose: The conformity of the achieved dose distribution to the treatment plan strongly correlates with the accuracy of seed implantation in a prostate brachytherapy treatment procedure. Incorrect seed placement leads to both short and long term complications, including urethral and rectal toxicity. The authors present BrachyView, a novel concept of a fast intraoperative treatment planning system, to provide real-time seed placement information based on in-body gamma camera data. BrachyView combines the high spatial resolution of a pixellated silicon detector (Medipix2) with the volumetric information acquired by a transrectal ultrasound (TRUS). The two systems will be embedded in the same probe so as to provide anatomically correct seed positions for intraoperative planning and postimplant dosimetry. Dosimetric calculations are based on the TG-43 method using the real position of the seeds. The purpose of this paper is to demonstrate the feasibility of BrachyView using the Medipix2 pixel detector and a pinhole collimator to reconstruct the real-time 3D position of low dose-rate brachytherapy seeds in a phantom. Methods: BrachyView incorporates three Medipix2 detectors coupled to a multipinhole collimator. Three-dimensionally triangulated seed positions from multiple planar images are used to determine the seed placement in a PMMA prostate phantom in real time. MATLAB codes were used to test the reconstruction method and to optimize the device geometry. Results: The results presented in this paper show a 3D position reconstruction accuracy of the seed in the range of 0.5-3 mm for a 10-60 mm seed-to-detector distance interval (Z direction), respectively. The BrachyView system also demonstrates a spatial resolution of 0.25 mm in the XY plane for sources at 10 mm distance from Medipix2 detector plane, comparable to the theoretical value calculated for an equivalent gamma camera arrangement. The authors successfully demonstrated the capability of BrachyView for real

  17. SU-E-J-93: Parametrisation of Dose to the Mucosa of the Anterior Rectal Wall in Transrectal Ultrasound Guided High-Dose-Rate Brachytherapy of the Prostate

    SciTech Connect

    Aitkenhead, A; Hamlett, L; Wood, D; Choudhury, A

    2014-06-01

    Purpose: In high-dose-rate (HDR) brachytherapy of the prostate, radiation is delivered from a number of radioactive sources which are inserted via catheter into the target volume. The rectal mucosa also receives dose during the treatment, which may lead to late toxicity effects. To allow possible links between rectal dose and toxicity to be investigated, suitable methods of parametrising the rectal dose are needed. Methods: During treatment of a series of 95 patients, anatomy and catheter locations were monitored by transrectal ultrasound, and target volume positions were contoured on the ultrasound scan by the therapist. The anterior rectal mucosal wall was identified by contouring the transrectal ultrasound balloon within the ultrasound scan. Source positions and dwell times, along with the dose delivered to the patient were computed using the Oncentra Prostate treatment planning system (TPS). Data for the series of patients were exported from the TPS in Dicom format, and a series of parametrisation methods were developed in a Matlab environment to assess the rectal dose. Results: Contours of the anterior rectal mucosa were voxelised within Matlab to allow the dose to the rectal mucosa to be analysed directly from the 3D dose grid. Dose parametrisations based on dose-surface (DSH) and dose-line (DLH) histograms were obtained. Both lateral and longitudinal extents of the mucosal dose were parametrised using dose-line histograms in the relevant directions. Conclusion: We have developed a series of dose parametrisations for quantifying the dose to the rectal mucosa during HDR prostate brachytherapy which are suitable for future studies investigating potential associations between mucosal dose and late toxicity effects. The geometry of the transrectal probe standardises the rectal anatomy, making this treatment technique particularly suited to studies of this nature.

  18. Monte Carlo investigation of I-125 interseed attenuation for standard and thinner seeds in prostate brachytherapy with phantom validation using a MOSFET

    SciTech Connect

    Mason, J.; Al-Qaisieh, B.; Bownes, P.; Henry, A.; Thwaites, D.

    2013-03-15

    Purpose: In permanent seed implant prostate brachytherapy the actual dose delivered to the patient may be less than that calculated by TG-43U1 due to interseed attenuation (ISA) and differences between prostate tissue composition and water. In this study the magnitude of the ISA effect is assessed in a phantom and in clinical prostate postimplant cases. Results are compared for seed models 6711 and 9011 with 0.8 and 0.5 mm diameters, respectively. Methods: A polymethyl methacrylate (PMMA) phantom was designed to perform ISA measurements in a simple eight-seed arrangement and at the center of an implant of 36 seeds. Monte Carlo (MC) simulation and experimental measurements using a MOSFET dosimeter were used to measure dose rate and the ISA effect. MC simulations of 15 CT-based postimplant prostate treatment plans were performed to compare the clinical impact of ISA on dose to prostate, urethra, rectum, and the volume enclosed by the 100% isodose, for 6711 and 9011 seed models. Results: In the phantom, ISA reduced the dose rate at the MOSFET position by 8.6%-18.3% (6711) and 7.8%-16.7% (9011) depending on the measurement configuration. MOSFET measured dose rates agreed with MC simulation predictions within the MOSFET measurement uncertainty, which ranged from 5.5% to 7.2% depending on the measurement configuration (k= 1, for the mean of four measurements). For 15 clinical implants, the mean ISA effect for 6711 was to reduce prostate D90 by 4.2 Gy (3%), prostate V100 by 0.5 cc (1.4%), urethra D10 by 11.3 Gy (4.4%), rectal D2cc by 5.5 Gy (4.6%), and the 100% isodose volume by 2.3 cc. For the 9011 seed the mean ISA effect reduced prostate D90 by 2.2 Gy (1.6%), prostate V100 by 0.3 cc (0.7%), urethra D10 by 8.0 Gy (3.2%), rectal D2cc by 3.1 Gy (2.7%), and the 100% isodose volume by 1.2 cc. Differences between the MC simulation and TG-43U1 consensus data for the 6711 seed model had a similar impact, reducing mean prostate D90 by 6 Gy (4.2%) and V100 by 0.6 cc (1

  19. Brachytherapy Improves Biochemical Failure–Free Survival in Low- and Intermediate-Risk Prostate Cancer Compared With Conventionally Fractionated External Beam Radiation Therapy: A Propensity Score Matched Analysis

    SciTech Connect

    Smith, Graham D.; Pickles, Tom; Crook, Juanita; Martin, Andre-Guy; Vigneault, Eric; Cury, Fabio L.; Morris, Jim; Catton, Charles; Lukka, Himu; Warner, Andrew; Yang, Ying; Rodrigues, George

    2015-03-01

    Purpose: To compare, in a retrospective study, biochemical failure-free survival (bFFS) and overall survival (OS) in low-risk and intermediate-risk prostate cancer patients who received brachytherapy (BT) (either low-dose-rate brachytherapy [LDR-BT] or high-dose-rate brachytherapy with external beam radiation therapy [HDR-BT+EBRT]) versus external beam radiation therapy (EBRT) alone. Methods and Materials: Patient data were obtained from the ProCaRS database, which contains 7974 prostate cancer patients treated with primary radiation therapy at four Canadian cancer institutions from 1994 to 2010. Propensity score matching was used to obtain the following 3 matched cohorts with balanced baseline prognostic factors: (1) low-risk LDR-BT versus EBRT; (2) intermediate-risk LDR-BT versus EBRT; and (3) intermediate-risk HDR-BT+EBRT versus EBRT. Kaplan-Meier survival analysis was performed to compare differences in bFFS (primary endpoint) and OS in the 3 matched groups. Results: Propensity score matching created acceptable balance in the baseline prognostic factors in all matches. Final matches included 2 1:1 matches in the intermediate-risk cohorts, LDR-BT versus EBRT (total n=254) and HDR-BT+EBRT versus EBRT (total n=388), and one 4:1 match in the low-risk cohort (LDR-BT:EBRT, total n=400). Median follow-up ranged from 2.7 to 7.3 years for the 3 matched cohorts. Kaplan-Meier survival analysis showed that all BT treatment options were associated with statistically significant improvements in bFFS when compared with EBRT in all cohorts (intermediate-risk EBRT vs LDR-BT hazard ratio [HR] 4.58, P=.001; intermediate-risk EBRT vs HDR-BT+EBRT HR 2.08, P=.007; low-risk EBRT vs LDR-BT HR 2.90, P=.004). No significant difference in OS was found in all comparisons (intermediate-risk EBRT vs LDR-BT HR 1.27, P=.687; intermediate-risk EBRT vs HDR-BT+EBRT HR 1.55, P=.470; low-risk LDR-BT vs EBRT HR 1.41, P=.500). Conclusions: Propensity score matched analysis showed that BT options led

  20. Dose Constraint for Minimizing Grade 2 Rectal Bleeding Following Brachytherapy Combined With External Beam Radiotherapy for Localized Prostate Cancer: Rectal Dose-Volume Histogram Analysis of 457 Patients

    SciTech Connect

    Shiraishi, Yutaka; Yorozu, Atsunori; Ohashi, Toshio; Toya, Kazuhito; Seki, Satoshi; Yoshida, Kayo; Kaneda, Tomoya; Saito, Shiro; Nishiyama, Toru; Hanada, Takashi; Shigematsu, Naoyuki

    2011-11-01

    Purpose: To determine the rectal tolerance to Grade 2 rectal bleeding after I-125 seed brachytherapy combined with external beam radiotherapy (EBRT), based on the rectal dose-volume histogram. Methods and Materials: A total of 458 consecutive patients with stages T1 to T3 prostate cancer received combined modality treatment consisting of I-125 seed implantation followed by EBRT to the prostate and seminal vesicles. The prescribed doses of brachytherapy and EBRT were 100 Gy and 45 Gy in 25 fractions, respectively. The rectal dosimetric factors were analyzed for rectal volumes receiving >100 Gy and >150 Gy (R100 and R150) during brachytherapy and for rectal volumes receiving >30 Gy to 40 Gy (V30-V40) during EBRT therapy in 373 patients for whom datasets were available. The patients were followed from 21 to 72 months (median, 45 months) after the I-125 seed implantation. Results: Forty-four patients (9.7%) developed Grade 2 rectal bleeding. On multivariate analysis, age (p = 0.014), R100 (p = 0.002), and V30 (p = 0.001) were identified as risk factors for Grade 2 rectal bleeding. The rectal bleeding rate increased as the R100 increased: 5.0% (2/40 patients) for 0 ml; 7.5% (20/267 patients) for >0 to 0.5 ml; 11.0% (11/100 patients) for >0.5 to 1 ml; 17.9% (5/28 patients) for >1 to 1.5 ml; and 27.3% (6/22 patients) for >1.5 ml (p = 0.014). Grade 2 rectal bleeding developed in 6.4% (12/188) of patients with a V30 {<=}35% and in 14.1% (26/185) of patients with a V30 >35% (p = 0.02). When these dose-volume parameters were considered in combination, the Grade 2 rectal bleeding rate was 4.2% (5/120 patients) for a R100 {<=}0.5 ml and a V30 {<=}35%, whereas it was 22.4% (13/58 patients) for R100 of >0.5 ml and V30 of >35%. Conclusion: The risk of rectal bleeding was found to be significantly volume-dependent in patients with prostate cancer who received combined modality treatment. Rectal dose-volume analysis is a practical method for predicting the risk of development of

  1. Prognostic Significance of 5-Year PSA Value for Predicting Prostate Cancer Recurrence After Brachytherapy Alone and Combined With Hormonal Therapy and/or External Beam Radiotherapy

    SciTech Connect

    Stock, Richard G. Klein, Thomas J.; Cesaretti, Jamie A.; Stone, Nelson N.

    2009-07-01

    Purpose: To analyze the prognosis and outcomes of patients who remain free of biochemical failure during the first 5 years after treatment. Methods and Materials: Between 1991 and 2002, 742 patients with prostate cancer were treated with brachytherapy alone (n = 306), brachytherapy and hormonal therapy (n = 212), or combined implantation and external beam radiotherapy (with or without hormonal therapy; n = 224). These patients were free of biochemical failure (American Society for Therapeutic Radiology and Oncology [ASTRO] definition) during the first 5 post-treatment years and had a documented 5-year prostate-specific antigen (PSA) value. The median follow-up was 6.93 years. Results: The actuarial 10-year freedom from PSA failure rate was 97% using the ASTRO definition and 95% using the Phoenix definition. The median 5-year PSA level was 0.03 ng/mL (range, 0-3.6). The 5-year PSA value was {<=}0.01 in 47.7%, >0.01-0.10 in 31.1%, >0.10-0.2 in 10.2%, >0.2-0.5 in 7.82%, and >0.5 in 3.10%. The 5-year PSA value had prognostic significance, with a PSA value of {<=}0.2 ng/mL (n = 661) corresponding to a 10-year freedom from PSA failure rate of 99% with the ASTRO definition and 98% with the Phoenix definition vs. 86% (ASTRO definition) and 81% (Phoenix definition) for a PSA value {>=}0.2 ng/mL (n = 81; p < .0001). The treatment regimen had no effect on biochemical failure. None of the 742 patients in this study developed metastatic disease or died of prostate cancer. Conclusion: The results of this study have shown that the prognosis for patients treated with brachytherapy and who remain biochemically free of disease for {>=}5 years is excellent and none developed metastatic disease during the first 10 years after treatment. The 5-year PSA value is prognostic, and patients with a PSA value <0.2 ng/mL are unlikely to develop subsequent biochemical relapse.

  2. Hypofractionated Boost With High-Dose-Rate Brachytherapy and Open Magnetic Resonance Imaging-Guided Implants for Locally Aggressive Prostate Cancer: A Sequential Dose-Escalation Pilot Study

    SciTech Connect

    Ares, Carmen; Popowski, Youri; Pampallona, Sandro; Nouet, Philippe; Dipasquale, Giovanna; Bieri, Sabine; Ozsoy, Orhan; Rouzaud, Michel; Khan, Haleem; Miralbell, Raymond

    2009-11-01

    Purpose: To evaluate the feasibility, tolerance, and preliminary outcome of an open MRI-guided prostate partial-volume high-dose-rate brachytherapy (HDR-BT) schedule in a group of selected patients with nonmetastatic, locally aggressive prostatic tumors. Methods and Materials: After conventional fractionated three-dimensional conformal external radiotherapy to 64-64.4 Gy, 77 patients with nonmetastatic, locally aggressive (e.g., perineural invasion and/or Gleason score 8-10) prostate cancer were treated from June 2000 to August 2004, with HDR-BT using temporary open MRI-guided {sup 192}Ir implants, to escalate the dose in the boost region. Nineteen, 21, and 37 patients were sequentially treated with 2 fractions of 6 Gy, 7 Gy, and 8 Gy each, respectively. Neoadjuvant androgen deprivation was given to 62 patients for 6-24 months. Acute and late toxicity were scored according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scoring system. Results: All 77 patients completed treatment as planned. Only 2 patients presented with Grade >=3 acute urinary toxicity. The 3-year probability of Grade >=2 late urinary and low gastrointestinal toxicity-free survival was 91.4% +- 3.4% and 94.4% +- 2.7%, respectively. Rates of 3-year biochemical disease-free survival (bDFS) and disease-specific survival were 87.1% +- 4.1% and 100%, respectively. Conclusions: Boosting a partial volume of the prostate with hypofractionated HDR-BT for aggressive prostate cancer was feasible and showed limited long-term toxicity, which compared favorably with other dose-escalation methods in the literature. Preliminary bDFS was encouraging if one considers the negatively selected population of high-risk patients in this study.

  3. Combination External Beam Radiation and Brachytherapy Boost With Androgen Suppression for Treatment of Intermediate-Risk Prostate Cancer: An Initial Report of CALGB 99809

    SciTech Connect

    Hurwitz, Mark D.; McGinnis, Lamar S.; Keuttel, Michael R.; DiBiase, Steven J.; Small, Eric J.

    2008-11-01

    Purpose: Transperineal prostate brachytherapy (TPPB) can be used with external beam radiation therapy (EBRT) to provide a high-dose conformal boost to the prostate. The results of a multicenter Phase II trial assessing safety of combination of EBRT and TPPB boost with androgen suppression (AST) in treatment of intermediate-risk prostate cancer are present here. Materials and Methods: Patients had intermediate-risk prostate cancer. Six months of AST was administered. EBRT to the prostate and seminal vesicles was administered to 45Gy followed by TPPB using either {sup 125}I or {sup 103}Pd to deliver an additional 100Gy or 90Gy. Toxicity was graded using the National Cancer Institute CTC version 2 and the Radiation Therapy Oncology Group late radiation morbidity scoring systems. Results: Sixty-three patients were enrolled. Median follow-up was 38 months. Side effects of AST including sexual dysfunction and vasomotor symptoms were commonly observed. Apart from erectile dysfunction, short-term Grade 2 and 3 toxicity was noted in 21% and 7%, primarily genitourinary related. Long-term Grade 2 and 3 toxicities were noted in 13% and 3%. Two patients had Grade 3 dysuria that resolved with longer follow-up. The most common Grade 2 long-term toxicity was urinary frequency (5%). No biochemical or clinical evidence of progression was noted for the entire cohort. Conclusions: In a cooperative group setting, combination EBRT and TPPB boost with 6 months of AST was generally well tolerated with expected genitourinary and gastrointestinal toxicities. Further follow-up will be required to fully assess long-term toxicity and cancer control.

  4. In vivo dosimetry in the urethra using alanine/ESR during (192)Ir HDR brachytherapy of prostate cancer--a phantom study.

    PubMed

    Anton, Mathias; Wagner, Daniela; Selbach, Hans-Joachim; Hackel, Thomas; Hermann, Robert Michael; Hess, Clemens Friedrich; Vorwerk, Hilke

    2009-05-01

    A phantom study for dosimetry in the urethra using alanine/ESR during (192)Ir HDR brachytherapy of prostate cancer is presented. The measurement method of the secondary standard of the Physikalisch-Technische Bundesanstalt had to be slightly modified in order to be able to measure inside a Foley catheter. The absorbed dose to water response of the alanine dosimetry system to (192)Ir was determined with a reproducibility of 1.8% relative to (60)Co. The resulting uncertainty for measurements inside the urethra was estimated to be 3.6%, excluding the uncertainty of the dose rate constant Lambda. The applied dose calculated by a treatment planning system is compared to the measured dose for a small series of (192)Ir HDR irradiations in a gel phantom. The differences between the measured and applied dose are well within the limits of uncertainty. Therefore, the method is considered to be suitable for measurements in vivo.

  5. Treatment Results of PDR Brachytherapy Combined With External Beam Radiotherapy in 106 Patients With Intermediate- to High-Risk Prostate Cancer

    SciTech Connect

    Pieters, Bradley R.

    2011-03-15

    Purpose: To evaluate treatment outcome of pulsed dose-rate brachytherapy (PDR) combined with external-beam radiotherapy (EBRT) for the treatment of prostate cancer. Methods and Materials: Between 2002 and 2007, 106 patients were treated by EBRT combined with PDR and followed prospectively. Two, 38, and 66 patients were classified as low-, intermediate-, and high-risk disease respectively according to the National Comprehensive Cancer Network criteria. EBRT dose was 46 Gy in 2.0-Gy fractions. PDR dose was increased stepwise from 24.96 to 28.80 Gy. Biochemical disease free survival and overall survival were determined by the Kaplan-Meier method. Cumulative incidence of late gastrointestinal (GI) and genitourinary (GU) toxicity were scored, according to the Common Terminology Criteria for Adverse Events. Results: The 3- and 5-year biochemical nonevidence of disease (bNED) were 92.8% (95% confidence interval [CI], 87.1-98.5) and 89.5% (95% CI, 85.2-93.8), respectively. Overall survival at 3 and 5 years was 99% (95% CI, 96-100) and 96% (95% CI, 90-100), respectively. The 3- and 5-year Grade 2 GI toxicity was 5.3% (95% CI, 0-10.6) and 12.0% (95% CI, 1.4-22.6), respectively. No Grade 3 or higher GI toxicity was observed. The 3- and 5-year Grade 2 or higher GU toxicity was 18.7% (95% CI, 10.3-27.1) and 26.9% (95% CI, 15.1-38.7), respectively. Conclusion: Results on tumor control and late toxicity of EBRT combined with PDR are good and comparable to results obtained with EBRT combined with high-dose-rate brachytherapy for the treatment of prostate cancer.

  6. Health-Related Quality of Life After Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiotherapy for Prostate Cancer

    SciTech Connect

    Morton, Gerard C.; Loblaw, D. Andrew; Chung, Hans; Tsang, Gail; Sankreacha, Raxa; Deabreu, Andrea; Zhang Liying; Mamedov, Alexandre; Cheung, Patrick; Batchelar, Deidre; Danjoux, Cyril; Szumacher, Ewa

    2011-08-01

    Purpose: To investigate the change in health-related quality of life for men after high-dose-rate brachytherapy and external beam radiotherapy for prostate cancer and the factors associated with this change. Methods and Materials: Eligible patients had clinically localized intermediate-risk prostate cancer. The patients received high-dose-rate brachytherapy as a single 15-Gy implant, followed by external beam radiotherapy to 37.5 Gy in 15 fractions. The patients were monitored prospectively for toxicity (Common Terminology Criteria for Adverse Events, version 3.0) and health-related quality of life (Expanded Prostate Cancer Index Composite [EPIC]). The proportion of patients developing a clinically significant difference in the EPIC domain score (minimally important difference of >0.5 standard deviation) was determined and correlated with the baseline clinical and dosimetric factors. The study accrued 125 patients, with a median follow-up of 24 months. Results: By 24 months, 23% had Grade 2 urinary toxicity and only 5% had Grade 2 bowel toxicity, with no Grade 3 toxicity. The proportion of patients reporting a significant decrease in EPIC urinary, bowel, sexual, and hormonal domain scores was 53%, 51%, 45%, and 40% at 12 months and 57%, 65%, 51%, and 30% at 24 months, respectively. The proportion with a >1 standard deviation decrease in the EPIC urinary, bowel, sexual, and hormonal domain scores was 38%, 36%, 24%, and 20% at 12 months and 46%, 48%, 19%, and 8% at 24 months, respectively. On multivariate analysis, the dose to 10% of the urethra was associated with a decreasing EPIC urinary domain score (p = .0089) and, less strongly (p = .0312) with a decreasing hormonal domain score. No association was found between the prostate volume, bladder dose, or high-dose volume and urinary health-related quality of life. A high baseline International Index of Erectile Function score was associated (p = .0019) with a decreasing sexual domain score. The optimal maximal dose

  7. SU-E-T-620: Dosimetric Compliance Study for a New Prostate Protocol of Combined High Dose Rate Brachytherapy and Stereotactic Body Radiotherapy

    SciTech Connect

    Peng, C; Giaddui, T; Den, R; Harrison, A; Yu, Y

    2014-06-15

    Purpose: To investigate the adherence of treatment plans of prostate cancer patients with the dosimetric compliance criteria of the new in house phase I trial of high dose rate (HDR) brachytherapy combined with stereotactic body radiotherapy (SBRT) for intermediate risk prostate cancer patients. Methods: Ten prostate cancer patients were treated using this trial. They received one fraction of HDR to 15Gy, followed by external beam(EB) boost of 3.2Gy(Level 1, five patients) or 3.94Gy(level 2, five patients) per fraction for 10 or 7 fractions, respectively, both equivalent to EB treatments of 113.5Gy in 2Gy fractions. The EB plans were either IMRT or VMAT plans. DVH analysis was performed to verify the adherence of treatment plans to the dosimetric criteria of the trial. Results: For Level 1 patients, target coverage were adequate, with CTV V32Gy(%) of 99.0±1.0 (mean ± 1 standard deviation), and PTV V31Gy(%) of 99.6±0.3. PTV V32.9Gy(%) is 1.4±3.1 and PTVmax is 32.9±0.2Gy. Rectum, bladder and femoral heads sparing were well within protocol criteria. For Level 2 patients, CTV V27.6Gy(%) is 98.7±1.8; PTV V26.7Gy(%) is 99.0±1.4. PTV V28.4Gy(%) is 1.3±1.4, with three patients having minor deviation from protocol. Again critical structures were spared compliant to the protocol. The analysis of HDR plans show similar results, with adequate dose coverage to the prostate and sparing of critical structures including urethra and rectum. V100(%) and V90(%) of prostate are 96.0±1.1 and 98.9±0.5. Urethra D10(%) is 113.1±2.9. Rectum V80(cc) is 1.4±0.5. Hotspot in prostate is substantially higher than what the protocol specifies. But the criteria for hotspot are only guidelines, serving to lower the dose to urethra . Conclusion: This new high biological equivalent dose prostate trial has been carried out successfully for ten patients. Based on dosimetric analysis, all HDR and external plans were compliant to the protocol criteria, with only minor deviations.

  8. Patterns of Recurrence After Low-Dose-Rate Prostate Brachytherapy: A Population-Based Study of 2223 Consecutive Low- and Intermediate-Risk Patients

    SciTech Connect

    Lo, Andrea C.; Morris, W. James Pickles, Tom; Keyes, Mira; McKenzie, Michael; Tyldesley, Scott

    2015-03-15

    Objectives: This study examined patterns of recurrence after low–dose-rate prostate brachytherapy (LDR-PB), estimated local recurrence rate and compared that rate to the estimated local recurrence rate after radical prostatectomy (RP). Methods and Materials: A prospective database was maintained with clinical, dosimetric, and outcome data for all LDR-PB implantation procedures performed at our institution. From 1998 to 2008, 2223 patients with prostate cancer received LDR-PB without supplemental external beam radiation therapy. Patients who developed Phoenix-defined biochemical failure were reviewed for sites of relapse and investigations completed. Results: At a median follow-up of 5 years, 108 of 2223 patients (4.8%) developed biochemical relapse. In 1 additional patient, local relapse was found on transurethral prostate resection, but his prostate-specific antigen concentration was well short of triggering Phoenix-defined failure. Of the 109 patients with disease relapse, 18 of 2223 (0.8%) had a proven local recurrence, and 30 of 2223 (1.3%) had a proven distant recurrence. The remaining 61 of 2223 patients (2.7%) had unidentified sites of recurrence; of these, 57 patients (93%) had digital rectal examinations (DREs), 18 (30%) had post-treatment biopsies, 45 (74%) had bone scans, and 34 (56%) had computed tomography imaging of the abdomen and pelvis. If every biochemical failure were local, the local recurrence rate would be as high as 4.9%; however, by excluding those with proven distant failure and those with both a negative DRE and biopsy, we estimate that the local recurrence rate is 2.7% or less. Conclusions: In the context of limitations of the study design, our population-based analysis indicates that the local recurrence rate after LDR-PB is as low or lower than that after RP in our jurisdiction.

  9. Hemiablative Focal Low Dose Rate Brachytherapy: A Phase II Trial Protocol

    PubMed Central

    Bucci, Joseph; Chin, Yaw Sinn; Malouf, David; Howie, Andrew; Enari, Komiti Ese

    2016-01-01

    Background The objective of focal brachytherapy (BT) is to provide effective prostate cancer control for low-risk disease but with reduced genitourinary, gastrointestinal and sexual side effects in a cost-effective way. Objective The aim of this study is to describe a phase II study examining technical and dosimetric feasibility and toxicity, quality of life changes, and local control with post-treatment biopsy outcomes in men with early stage low volume prostate cancer treated with focal iodine-125 seed BT. Methods The study design is a prospective, multicenter trial with a planned sample size of 20 patients including men with a minimum age of 60 years, a life expectancy estimated to be greater than 10 years, with low or low-tier intermediate risk prostate cancer, unilateral disease on the biopsy, and a Gleason score of ≤3+4 and <25% cores involved. The investigations specific for the study are multi-parametric magnetic resonance imaging (Mp-MRI) baseline, at 20 and 36 months to rule out high grade disease and a transperineal mapping biopsy (baseline and at 36 months) for more accurate patient selection. The hemigland region will receive 144 Gy. Standard normal tissue constraints will be considered as for a whole gland (WG) implant. Dosimetric parameters will be evaluated at day 30 after the implant. Toxicity and quality of life will be evaluated with international validated questionnaires focusing on urinary, rectal, sexual domain, and general health-related quality of life. The patients will complete this assessment at baseline and then approximately every 6 months after the implant up to 10 years. Results To date, one patient is involved in the trial. He underwent the pre-implant investigations which found bilateral disease. Therefore, a standard seed implant was performed. If the results from this trial provide evidence that the treatment is safe, feasible, and improves toxicity, funding will be sought to conduct a large, multicenter, randomized controlled

  10. Prostate brachytherapy - discharge

    MedlinePlus

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  11. Correlation Between Dosimetric Parameters and Late Rectal and Urinary Toxicities in Patients Treated With High-Dose-Rate Brachytherapy Used as Monotherapy for Prostate Cancer

    SciTech Connect

    Konishi, Koji; Yoshioka, Yasuo; Isohashi, Fumiaki; Sumida, Iori; Kawaguchi, Yoshifumi; Kotsuma, Tadayuki; Adachi, Kana; Morimoto, Masahiro; Fukuda, Shoichi; Inoue, Takehiro

    2009-11-15

    Purpose: To evaluate the correlation between dosimetric parameters and late rectal and urinary toxicities in high-dose-rate brachytherapy (HDR-BT) used as monotherapy for prostate cancer. Methods and Materials: The data of 83 patients treated with HDR-BT alone for prostate cancer from 2001 through 2005 at Osaka University Hospital were analyzed. Median follow-up time was 36 months (range, 18-70). The total prescribed dose was 54 Gy in nine fractions over 5 days. Correlation between dosimetric parameters and late toxicities was examined. Results: The means of V30, V40, V50, V60, V70, D1cc, D2cc, D5cc, and D10cc of the rectum were significantly higher in 18 patients who presented with late rectal toxicity (Grades 1-3 rectal bleeding) than in the other 65 patients who did not. A significant difference was observed for D1cc-10cc but not for D5-90. The statistically most significant difference was observed for V40 and D5cc. Late rectal toxicity rate was significantly higher for patients with rectal V40 >= 8 cc than those with the rectal V40 < 8 cc (42% vs. 8%; p < 0.001), as well as for patients with rectal D5cc >= 27 Gy compared with those with rectal D5cc < 27 Gy (50% vs. 11%; p < 0.001). Dosimetric parameters of the urethra of 15 patients with late urinary toxicity were not significantly different from the 68 patients without toxicity. Conclusion: Rectal V40 < 8 cc and D5cc < 27 Gy may be dose-volume constraints in HDR-BT used as monotherapy for prostate cancer.

  12. High-Dose-Rate Brachytherapy and External-Beam Radiotherapy for Hormone-Naieve Low- and Intermediate-Risk Prostate Cancer: A 7-Year Experience

    SciTech Connect

    Aluwini, Shafak; Rooij, Peter H. van; Kirkels, Wim J.; Jansen, Peter P.; Praag, John O.; Bangma, Chris H.; Kolkman-Deurloo, Inger-Karine K.

    2012-08-01

    Purpose: To report clinical outcomes and early and late complications in 264 hormone-naieve patients with low- and intermediate-risk prostate cancer treated with high-dose-rate brachytherapy (HDR-BT) in combination with external-beam radiotherapy (EBRT). Methods and Materials: Between February 2000 and July 2007, 264 patients underwent HDR-BT in combination with EBRT as a treatment for their low- to intermediate-risk prostate cancer. The HDR-BT was performed using ultrasound-based implantation. The total HDR-BT dose was 18 Gy in 3 fractions within 24 h, with a 6-h minimum interval. The EBRT started 2 weeks after HDR-BT and was delivered in 25 fractions of 1.8 Gy to 45 Gy within 5 weeks. Results: After a mean follow-up of 74.5 months, 4 patients (1.5%) showed prostate-specific antigen progression according to the American Society for Radiation Oncology definition and 8 patients (3%) according to the Phoenix definition. A biopsy-proven local recurrence was registered in 1 patient (0.4%), and clinical progression (bone metastases) was documented in 2 patients (0.7%). Seven-year actuarial freedom from biochemical failure was 97%, and 7-year disease-specific survival and overall survival were 100% and 91%, respectively. Toxicities were comparable to other series. Conclusions: Treatment with interstitial HDR-BT plus EBRT shows a low incidence of late complications and a favorable oncologic outcome after 7 years follow-up.

  13. Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiation Therapy in the Treatment of Intermediate-Risk Prostate Cancer - Long Term Results

    SciTech Connect

    Cury, Fabio L.; Duclos, Marie; Aprikian, Armen; Patrocinio, Horacio; Kassouf, Wassim; Shenouda, George; Faria, Sergio; David, Marc; Souhami, Luis

    2012-03-15

    Purpose: We present the long-term results of a cohort of patients with intermediate-risk prostate cancer (PC) treated with single-fraction high-dose-rate brachytherapy (HDRB) combined with hypofractionated external beam radiation therapy (HypoRT). Methods and Materials: Patients were treated exclusively with HDRB and HypoRT. HDRB delivered a dose of 10 Gy to the prostate surface and HypoRT consisted of 50 Gy delivered in 20 daily fractions. The first 121 consecutive patients with a minimum of 2 years posttreatment follow-up were assessed for toxicity and disease control. Results: The median follow-up was 65.2 months. No acute Grade III or higher toxicity was seen. Late Grade II gastrointestinal toxicity was seen in 9 patients (7.4%) and Grade III in 2 (1.6%). Late Grade III genitourinary toxicity was seen in 2 patients (1.6%). After a 24-month follow-up, a rebiopsy was offered to the first 58 consecutively treated patients, and 44 patients agreed with the procedure. Negative biopsies were found in 40 patients (91%). The 5-year biochemical relapse-free survival rate was 90.7% (95% CI, 84.5-96.9%), with 13 patients presenting biochemical failure. Among them, 9 were diagnosed with distant metastasis. Prostate cancer-specific and overall survival rates at 5 years were 100% and 98.8% (95% CI, 96.4-100%), respectively. Conclusion: The combination of HDRB and HypoRT is well tolerated, with acceptable toxicity rates. Furthermore, results from rebiopsies revealed an encouraging rate of local control. These results confirm that the use of conformal RT techniques, adapted to specific biological tumor characteristics, have the potential to improve the therapeutic ratio in intermediate-risk PC patients.

  14. SU-C-16A-01: In Vivo Source Position Verification in High Dose Rate (HDR) Prostate Brachytherapy Using a Flat Panel Imager: Initial Clinical Experience

    SciTech Connect

    Franich, R; Smith, R; Millar, J; Haworth, A; Taylor, M; McDermott, L

    2014-06-15

    Purpose: We report our initial clinical experience with a novel position-sensitive source-tracking system based on a flat panel imager. The system has been trialled with 4 prostate HDR brachytherapy patients (8 treatment fractions) in this initial study. Methods: The flat panel imaging system was mounted under a customised carbon fibre couch top assembly (Figure 1). Three gold fiducial markers were implanted into the prostate of each patient at the time of catheter placement. X-ray dwell position markers were inserted into three catheters and a radiograph acquired to locate the implant relative to the imaging device. During treatment, as the HDR source dwells were delivered, images were acquired and processed to determine the position of the source in the patient. Source positions measured by the imaging device were compared to the treatment plan for verification of treatment delivery. Results: Measured dwell positions provided verification of relative dwell spacing within and between catheters, in the coronal plane. Measurements were typically within 2.0mm (0.2mm – 3.3mm, s.d. 0.8mm) of the planned positions over 60 dwells (Figure 2). Discrimination between larger dwell intervals and catheter differentiation were clear. This confirms important delivery attributes such as correct transfer tube connection, source step size, relative catheter positions and therefore overall correct plan selection and delivery. The fiducial markers, visible on the radiograph, provided verification of treatment delivery to the correct anatomical location. The absolute position of the dwells was determined by comparing the measured dwell positions with the x-ray markers from the radiograph, validating the programmed treatment indexer length. The total impact on procedure time was less than 5 minutes. Conclusion: The novel, noninvasive HDR brachytherapy treatment verification system was used clinically with minor impact on workflow. The system allows verification of correct treatment

  15. Anatomy-based inverse optimization in high-dose-rate brachytherapy combined with hypofractionated external beam radiotherapy for localized prostate cancer: Comparison of incidence of acute genitourinary toxicity between anatomy-based inverse optimization and geometric optimization

    SciTech Connect

    Akimoto, Tetsuo . E-mail: takimoto@showa.gunma-u.ac.jp; Katoh, Hiroyuki; Kitamoto, Yoshizumi; Shirai, Katsuyuki; Shioya, Mariko; Nakano, Takashi

    2006-04-01

    Purpose: To evaluate the advantages of anatomy-based inverse optimization (IO) in planning high-dose-rate (HDR) brachytherapy. Methods and Materials: A total of 114 patients who received HDR brachytherapy (9 Gy in two fractions) combined with hypofractionated external beam radiotherapy (EBRT) were analyzed. The dose distributions of HDR brachytherapy were optimized using geometric optimization (GO) in 70 patients and by anatomy-based IO in the remaining 44 patients. The correlation between the dose-volume histogram parameters, including the urethral dose and the incidence of acute genitourinary (GU) toxicity, was evaluated. Results: The averaged values of the percentage of volume receiving 80-150% of the prescribed minimal peripheral dose (V{sub 8}-V{sub 15}) of the urethra generated by anatomy-based IO were significantly lower than the corresponding values generated by GO. Similarly, the averaged values of the minimal dose received by 5-50% of the target volume (D{sub 5}-D{sub 5}) obtained using anatomy-based IO were significantly lower than those obtained using GO. Regarding acute toxicity, Grade 2 or worse acute GU toxicity developed in 23% of all patients, but was significantly lower in patients for whom anatomy-based IO (16%) was used than in those for whom GO was used (37%), consistent with the reduced urethral dose (p <0.01). Conclusion: The results of this study suggest that anatomy-based IO is superior to GO for dose optimization in HDR brachytherapy for prostate cancer.

  16. Vital role of volume and number of needles in HDR brachytherapy (HDR-BT) of prostate cancer

    PubMed Central

    Kanikowski, Marek; Skowronek, Janusz

    2009-01-01

    Purpose The quality of HDR-BT of prostate cancer depends on operator skills, anatomy, prostate volume and relation to surrounding tissues as well as previous diseases and treatments of a patient. There is a rare data available concerning the minimum number of needles and its influence on dose distribution, side effects and long-term outcome. The study is to determine the minimal prostate volume and minimum number of needles suitable for HDR-BT in order to obtain an implant of good quality. Material and methods 181 patients with localized prostate cancer were treated with interstitial HDR-BT boost. 15 Gy from HDR-BT was administered after 50 Gy from EBRT. Clinical, volumetric and dosimetric data were collected. Treatment plans were divided into Group A, consisted of optimal treatment plans (P-D90 > 90%, P-V200 < 15%, U-D10 < 125%, U-Dmax < 160%, R-D10 < 85%) and Group B, with suboptimal plans. Results The difference between two groups was statistically significant (p = 0.013) with regard to number of needles. There was no statistically significant difference concerning prostatic volume. Median number of inserted needles in the first and the second group resulted in 15 (range 9-18) and 13 (range 8-18), respectively. Differences were the most eminent in patients with prostate glands of small volume (< 20 cc). In the study, either the minimum number of needles nor minimal prostate gland volume were not clearly defined in terms of high probability of achieving a good quality implant. Conclusions Larger volume and higher number of needles are related to an advanced probability of treatment plan with all DVC fulfilled. The minimum number of needles suggested is > 9, optimally ≥ 13. Furthermore, the minimal prostate volume recommended is > 12 cc, optimally ≥ 18 cc. The volume of insufficient size and/or small number of needles results in suboptimal treatment plans.

  17. The Number of High-Risk Factors and the Risk of Prostate Cancer-Specific Mortality After Brachytherapy: Implications for Treatment Selection

    SciTech Connect

    Wattson, Daniel A.; Chen Minghui; Moul, Judd W.; Moran, Brian J.; Dosoretz, Daniel E.; Robertson, Cary N.; Polascik, Thomas J.; Braccioforte, Michelle H.; Salenius, Sharon A.; D'Amico, Anthony V.

    2012-04-01

    Purpose: To determine whether an increasing number of high-risk factors is associated with higher prostate cancer-specific mortality (PCSM) among men treated with brachytherapy (BT)-based treatment, and whether supplemental therapy has an impact on this risk. Methods and Materials: We analyzed the cases of 2234 men with localized prostate cancer treated between 1991 and 2007 with low-dose rate BT monotherapy (n = 457) or BT with supplemental external-beam radiotherapy (EBRT, n = 229), androgen suppression therapy (AST, n = 424), or both (n = 1124). All men had at least one high-risk factor (prostate-specific antigen >20 ng/mL, biopsy Gleason score 8-10, or clinical stage {>=}T2c). Competing-risks multivariable regressions were performed to determine whether the presence of at least two high-risk factors was associated with an increased risk of PCSM, with adjustment for age, comorbidity, and the type of supplemental treatment. Results: The median follow-up time was 4.3 years. The number of men with at least two high-risk factors was highest in the group treated with BT, EBRT, and AST (21%), followed by BT plus EBRT or AST (13%), and BT alone (8%) (p{sub trend} < 0.001). The adjusted hazard ratio (AHR) for PCSM for those with at least two high-risk factors (as compared with one) was 4.8 (95% confidence interval [CI], 2.8-8.0; p < 0.001). The use of both supplemental EBRT and AST was associated with a decreased risk of PCSM (AHR 0.5; 95% CI, 0.2-0.9; p = 0.03) compared with BT alone. When the high-risk factors were analyzed separately, Gleason score 8-10 was most significantly associated with increased PCSM (AHR 6.2; 95% CI, 3.5-11.2; p < 0.001). Conclusions: Men with high-risk prostate adenocarcinoma treated with BT have decreased PCSM if they receive trimodailty therapy that includes EBRT and AST. This benefit is likely most important in men with multiple determinants of high risk.

  18. Dosimetric differences between intraoperative and postoperative plans using Cs-131 in transrectal ultrasound–guided brachytherapy for prostatic carcinoma

    SciTech Connect

    Jones, Andrew; Treas, Jared; Yavoich, Brian; Dean, Douglas; Danella, John; Yumen, Omar

    2014-01-01

    The aim of the study was to investigate the differences between intraoperative and postoperative dosimetry for transrectal ultrasound–guided transperineal prostate implants using cesium-131 ({sup 131}Cs). Between 2006 and 2010, 166 patients implanted with {sup 131}Cs had both intraoperative and postoperative dosimetry studies. All cases were monotherapy and doses of 115 were prescribed to the prostate. The dosimetric properties (D{sub 90}, V{sub 150}, and V{sub 100} for the prostate) of the studies were compared. Two conformity indices were also calculated and compared. Finally, the prostate was automatically sectioned into 6 sectors (anterior and posterior sectors at the base, midgland, and apex) and the intraoperative and postoperative dosimetry was compared in each individual sector. Postoperative dosimetry showed statistically significant changes (p < 0.01) in every dosimetric value except V{sub 150}. In each significant case, the postoperative plans showed lower dose coverage. The conformity indexes also showed a bimodal frequency distribution with the index indicating poorer dose conformity in the postoperative plans. Sector analysis revealed less dose coverage postoperatively in the base and apex sectors with an increase in dose to the posterior midgland sector. Postoperative dosimetry overall and in specific sectors of the prostate differs significantly from intraoperative planning. Care must be taken during the intraoperative planning stage to ensure complete dose coverage of the prostate with the understanding that the final postoperative dosimetry will show less dose coverage.

  19. Promising Long-Term Health-Related Quality of Life After High-Dose-Rate Brachytherapy Boost for Localized Prostate Cancer

    SciTech Connect

    Wahlgren, Thomas Nilsson, Sten; Lennernaes, Bo; Brandberg, Yvonne

    2007-11-01

    Purpose: To explore the long-term general and disease-specific health-related quality of life (HRQOL) >5 years after combined radiotherapy for localized prostate cancer, including a high-dose-rate brachytherapy boost and hormonal deprivation therapy. Methods and Materials: Of 196 eligible patients with localized prostate cancer (Stage T1-T3a) consecutively treated with curative radiotherapy at our institution between June 1998 and August 2000, 182 (93%) completed the European Organization for Research and Treatment of Cancer Quality of Life questionnaires QLQ-C30 and QLQ-PR25, including specific questions on fecal incontinence >5 years after treatment in September 2005. A comparison with age-matched normative data was done, as well as a longitudinal analysis using HRQOL data from a previous study. Results: The analysis included 158 nonrecurrent patients. Comparisons made with normative data showed that physical and role functioning were significantly better statistically and social functioning was significantly worse. Diarrhea and sleep disturbances were more pronounced and pain less pronounced than in a normal male population. The longitudinal analysis of disease-specific HRQOL showed that urinary urgency and erectile problems persisted 5 years after treatment, and nocturia and hormonally dependent symptoms had declined significantly, with a statistically significant difference. Fecal incontinence was recognized by 25% of patients, of whom 80% considered it a minor problem. Conclusion: More than 5 years after combined radiotherapy, irritative urinary problems and erectile dysfunction remain concerns, although severe bowel disturbance and fecal incontinence seem to be minor problems. Longitudinally, a decline mainly in hormonally dependent symptoms was seen. Minor differences in general HRQOL compared with normative data were observed, possibly including 'response shift' effects.

  20. Virtual HDR{sup SM} CyberKnife Treatment for Localized Prostatic Carcinoma: Dosimetry Comparison With HDR Brachytherapy and Preliminary Clinical Observations

    SciTech Connect

    Fuller, Donald B. Naitoh, John; Lee, Charles; Hardy, Steven C.; Jin, Haoran

    2008-04-01

    Background: We tested our ability to approximate the dose (38 Gy), fractionation (four fractions), and distribution of high-dose-rate (HDR) brachytherapy for prostate cancer with CyberKnife (CK) stereotactic body radiotherapy (SBRT) plans. We also report early clinical observations of CK SBRT treatment. Methods and Materials: Ten patients were treated with CK. For each CK SBRT plan, an HDR plan was designed using common contour sets and simulated HDR catheters. Planning target volume coverage, intraprostatic dose escalation, and urethra, rectum, and bladder exposure were compared. Results: Planning target volume coverage by the prescription dose was similar for CK SBRT and HDR plans, whereas percent of volume of interest receiving 125% of prescribed radiation dose (V125) and V150 values were higher for HDR, reflecting higher doses near HDR source dwell positions. Urethra dose comparisons were lower for CK SBRT in 9 of 10 cases, suggesting that CK SBRT may more effectively limit urethra dose. Bladder maximum point doses were higher with HDR, but bladder dose falloff beyond the maximum dose region was more rapid with HDR. Maximum rectal wall doses were similar, but CK SBRT created sharper rectal dose falloff beyond the maximum dose region. Second CK SBRT plans, constructed by equating urethra radiation dose received by point of maximum exposure of volume of interest to the HDR plan, significantly increased V125 and V150. Clinically, 4-month post-CK SBRT median prostate-specific antigen levels decreased 86% from baseline. Acute toxicity was primarily urologic and returned to baseline by 2 months. Acute rectal morbidity was minimal and transient. Conclusions: It is possible to construct CK SBRT plans that closely recapitulate HDR dosimetry and deliver the plans noninvasively.

  1. Evaluating the Phoenix Definition of Biochemical Failure After {sup 125}I Prostate Brachytherapy: Can PSA Kinetics Distinguish PSA Failures From PSA Bounces?

    SciTech Connect

    Thompson, Anna; Keyes, Mira; Pickles, Tom

    2010-10-01

    Purpose: To evaluate the prostate-specific antigen (PSA) kinetics of PSA failure (PSAf) and PSA bounce (PSAb) after permanent {sup 125}I prostate brachytherapy (PB). Methods and Materials: The study included 1,006 consecutive low and 'low tier' intermediate-risk patients treated with {sup 125}I PB, with a potential minimum follow-up of 4 years. Patients who met the Phoenix definition of biochemical failure (nadir + 2 ng/mL{sup -1}) were identified. If the PSA subsequently fell to {<=}0.5 ng/mL{sup -1}without intervention, this was considered a PSAb. All others were scored as true PSAf. Patient, tumor and dosimetric characteristics were compared between groups using the chi-square test and analysis of variance to evaluate factors associated with PSAf or PSAb. Results: Median follow-up was 54 months. Of the 1,006 men, 57 patients triggered the Phoenix definition of PSA failure, 32 (56%) were true PSAf, and 25 PSAb (44%). The median time to trigger nadir + 2 was 20.6 months (range, 6-36) vs. 49 mo (range, 12-83) for PSAb vs. PSAf groups (p < 0.001). The PSAb patients were significantly younger (p < 0.0001), had shorter time to reach the nadir (median 6 vs. 11.5 months, p = 0.001) and had a shorter PSA doubling time (p = 0.05). Men younger than age 70 who trigger nadir +2 PSA failure within 38 months of implant have an 80% likelihood of having PSAb and 20% chance of PSAf. Conclusions: With adequate follow-up, 44% of PSA failures by the Phoenix definition in our cohort were found to be benign PSA bounces. Our study reinforces the need for adequate follow-up when reporting PB PSA outcomes, to ensure accurate estimates of treatment efficacy and to avoid unnecessary secondary interventions.

  2. A comparison of needle tip localization accuracy using 2D and 3D trans-rectal ultrasound for high-dose-rate prostate cancer brachytherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Hrinivich, W. Thomas; Hoover, Douglas A.; Surry, Kathleen; Edirisinghe, Chandima; Montreuil, Jacques; D'Souza, David; Fenster, Aaron; Wong, Eugene

    2016-03-01

    Background: High-dose-rate brachytherapy (HDR-BT) is a prostate cancer treatment option involving the insertion of hollow needles into the gland through the perineum to deliver a radioactive source. Conventional needle imaging involves indexing a trans-rectal ultrasound (TRUS) probe in the superior/inferior (S/I) direction, using the axial transducer to produce an image set for organ segmentation. These images have limited resolution in the needle insertion direction (S/I), so the sagittal transducer is used to identify needle tips, requiring a manual registration with the axial view. This registration introduces a source of uncertainty in the final segmentations and subsequent treatment plan. Our lab has developed a device enabling 3D-TRUS guided insertions with high S/I spatial resolution, eliminating the need to align axial and sagittal views. Purpose: To compare HDR-BT needle tip localization accuracy between 2D and 3D-TRUS. Methods: 5 prostate cancer patients underwent conventional 2D TRUS guided HDR-BT, during which 3D images were also acquired for post-operative registration and segmentation. Needle end-length measurements were taken, providing a gold standard for insertion depths. Results: 73 needles were analyzed from all 5 patients. Needle tip position differences between imaging techniques was found to be largest in the S/I direction with mean+/-SD of -2.5+/-4.0 mm. End-length measurements indicated that 3D TRUS provided statistically significantly lower mean+/-SD insertion depth error of -0.2+/-3.4 mm versus 2.3+/-3.7 mm with 2D guidance (p < .001). Conclusions: 3D TRUS may provide more accurate HDR-BT needle localization than conventional 2D TRUS guidance for the majority of HDR-BT needles.

  3. Longitudinal assessment of quality of life after surgery, conformal brachytherapy, and intensity-modulated radiation therapy for prostate cancer

    PubMed Central

    Zelefsky, Michael J.; Poon, Bing Ying; Eastham, James; Vickers, Andrew; Pei, Xin; Scardino, Peter T.

    2016-01-01

    Purpose We evaluated quality-of-life changes (QoL) in 907 patients treated with either radical prostatectomy (open or laparoscopic), real-time planned conformal brachytherapy, or high-dose intensity-modulated radiotherapy (IMRT) on a prospective IRB-approved longitudinal study. Methods Validated questionnaires given pretreatment (baseline) and at 3, 6, 9, 12, 15, 18, 24, 36, and 48 months addressed urinary function, urinary bother, bowel function, bowel bother, sexual function, and sexual bother. Results At 48 months, surgery had significantly higher urinary incontinence than others (both P<.001), but fewer urinary irritation/obstruction symptoms (all P<.001). Very low levels of bowel dysfunction were observed and only small subsets in each group showed rectal bleeding. Brachytherapy and IMRT showed better sexual function than surgery accounting for baseline function and other factors (delta 14.29 of 100, 95% CI, 8.57–20.01; and delta 10.5, 95% CI, 3.78–17.88). Sexual bother was similar. Four-year outcomes showed persistent urinary incontinence for surgery with more obstructive urinary symptoms for radiotherapy. Using modern radiotherapy delivery, bowel function deterioration is less-often observed. Sexual function was strongly affected in all groups yet significantly less for radiotherapy. Conclusions Treatment selection should include patient preferences and balance predicted disease-free survival over a projected time vs potential impairment of QoL important for the patient. PMID:26780999

  4. Development of a magnetic resonance imaging protocol to visualize encapsulated contrast agent markers in prostate brachytherapy recipients: initial patient experience

    PubMed Central

    Lim, Tze Yee; Wang, Jihong; Bathala, Tharakeswara; Szklaruk, Janio; Pugh, Thomas J.; Mahmood, Usama; Ibbott, Geoffrey S.; Frank, Steven J.

    2016-01-01

    Purpose Computed tomography (CT)-based prostate post-implant dosimetry allows for definitive seed localization but is associated with high interobserver variation in prostate contouring. Currently, magnetic resonance imaging (MRI)-based post-implant dosimetry allows for accurate anatomical delineation but is limited due to inconsistent seed localization. Encapsulated contrast agent markers were previously proposed to overcome the seed localization limitation on MRI images by placing hyperintense markers adjacent to hypointense seeds. The aim of this study was to assess the appearance of these markers in prostatic tissue, and develop an MRI protocol to enable marker visualization. Material and methods We acquired MRI scans in prostate implant patients (n = 10) on day 0 (day of implant) and day 30 (month after implant). Before implantation of the markers, the routine post-implant MRI protocol included a 3D T2-weighted fast-spin-echo (FSE) sequence with which markers and seeds could not be clearly visualized. To visualize the MRI markers, a 3D fast radiofrequency-spoiled gradient-recalled echo (FSPGR) sequence was evaluated for marker and seed visibility, as well as prostate boundary definitions. Results The 3D FSPGR sequence allowed for the visualization of markers in the prostate, enabling the distinction of signal voids as seeds versus needle tracks. The updated post-implant MRI protocol consists of this 3D FSPGR scan and an optional 3D T2-weighted FSE scan. The optional 3D T2-weighted FSE sequence may be employed to better visualize intraprostatic detail. We also described the observed image artifacts, including seed susceptibility, marker chemical shift, partial volume averaging, motion, and wraparound artifacts. Conclusions We have demonstrated an MRI protocol for use with hyperintense encapsulated contrast agent markers to assist in the identification of hypointense seeds. PMID:27504133

  5. Magnetic Resonance Imaging (MRI) Markers for MRI-Guided High-Dose-Rate Brachytherapy: Novel Marker-Flange for Cervical Cancer and Marker Catheters for Prostate Cancer

    SciTech Connect

    Schindel, Joshua; Muruganandham, Manickam; Pigge, F. Christopher; Anderson, James; Kim, Yusung

    2013-06-01

    Purpose: To present a novel marker-flange, addressing source-reconstruction uncertainties due to the artifacts of a titanium intracavitary applicator used for magnetic resonance imaging (MRI)-guided high-dose-rate (HDR) brachytherapy (BT); and to evaluate 7 different MRI marker agents used for interstitial prostate BT and intracavitary gynecologic HDR BT when treatment plans are guided by MRI. Methods and Materials: Seven MRI marker agents were analyzed: saline solution, Conray-60, copper sulfate (CuSO{sub 4}) (1.5 g/L), liquid vitamin E, fish oil, 1% agarose gel (1 g agarose powder per 100 mL distilled water), and a cobalt–chloride complex contrast (C4) (CoCl{sub 2}/glycine = 4:1). A plastic, ring-shaped marker-flange was designed and tested on both titanium and plastic applicators. Three separate phantoms were designed to test the marker-flange, interstitial catheters for prostate BT, and intracavitary catheters for gynecologic HDR BT. T1- and T2-weighted MRI were analyzed for all markers in each phantom and quantified as percentages compared with a 3% agarose gel background. The geometric accuracy of the MR signal for the marker-flange was measured using an MRI-CT fusion. Results: The CuSO{sub 4} and C4 markers on T1-weighted MRI and saline on T2-weighted MRI showed the highest signals. The marker-flange showed hyper-signals of >500% with CuSO{sub 4} and C4 on T1-weighted MRI and of >400% with saline on T2-weighted MRI on titanium applicators. On T1-weighted MRI, the MRI signal inaccuracies of marker-flanges were measured <2 mm, regardless of marker agents, and that of CuSO{sub 4} was 0.42 ± 0.14 mm. Conclusion: The use of interstitial/intracavitary markers for MRI-guided prostate/gynecologic BT was observed to be feasible, providing accurate source pathway reconstruction. The novel marker-flange can produce extremely intense, accurate signals, demonstrating its feasibility for gynecologic HDR BT.

  6. Real-time catheter tracking for high-dose-rate prostate brachytherapy using an electromagnetic 3D-guidance device: A preliminary performance study

    SciTech Connect

    Zhou Jun; Sebastian, Evelyn; Mangona, Victor; Yan Di

    2013-02-15

    Purpose: In order to increase the accuracy and speed of catheter reconstruction in a high-dose-rate (HDR) prostate implant procedure, an automatic tracking system has been developed using an electromagnetic (EM) device (trakSTAR, Ascension Technology, VT). The performance of the system, including the accuracy and noise level with various tracking parameters and conditions, were investigated. Methods: A direct current (dc) EM transmitter (midrange model) and a sensor with diameter of 1.3 mm (Model 130) were used in the trakSTAR system for tracking catheter position during HDR prostate brachytherapy. Localization accuracy was assessed under both static and dynamic analyses conditions. For the static analysis, a calibration phantom was used to investigate error dependency on operating room (OR) table height (bottom vs midposition vs top), sensor position (distal tip of catheter vs connector end of catheter), direction [left-right (LR) vs anterior-posterior (AP) vs superior-inferior (SI)], sampling frequency (40 vs 80 vs 120 Hz), and interference from OR equipment (present vs absent). The mean and standard deviation of the localization offset in each direction and the corresponding error vectors were calculated. For dynamic analysis, the paths of five straight catheters were tracked to study the effects of directions, sampling frequency, and interference of EM field. Statistical analysis was conducted to compare the results in different configurations. Results: When interference was present in the static analysis, the error vectors were significantly higher at the top table position (3.3 {+-} 1.3 vs 1.8 {+-} 0.9 mm at bottom and 1.7 {+-} 1.0 mm at middle, p < 0.001), at catheter end position (3.1 {+-} 1.1 vs 1.4 {+-} 0.7 mm at the tip position, p < 0.001), and at 40 Hz sampling frequency (2.6 {+-} 1.1 vs 2.4 {+-} 1.5 mm at 80 Hz and 1.8 {+-} 1.1 at 160 Hz, p < 0.001). So did the mean offset errors in the LR direction (-1.7 {+-} 1.4 vs 0.4 {+-} 0.5 mm in AP and 0

  7. Fifteen-Year Biochemical Relapse-Free Survival, Cause-Specific Survival, and Overall Survival Following I{sup 125} Prostate Brachytherapy in Clinically Localized Prostate Cancer: Seattle Experience

    SciTech Connect

    Sylvester, John E.; Grimm, Peter D.; Wong, Jason; Galbreath, Robert W.; Merrick, Gregory; Blasko, John C.

    2011-10-01

    Purpose: To report 15-year biochemical relapse-free survival (BRFS), cause-specific survival (CSS), and overall survival (OS) outcomes of patients treated with I{sup 125} brachytherapy monotherapy for clinically localized prostate cancer early in the Seattle experience. Methods and Materials: Two hundred fifteen patients with clinically localized prostate cancer were consecutively treated from 1988 to 1992 with I{sup 125} monotherapy. They were prospectively followed as a tight cohort. They were evaluated for BRFS, CSS, and OS. Multivariate analysis was used to evaluate outcomes by pretreatment clinical prognostic factors. BRFS was analyzed by the Phoenix (nadir + 2 ng/mL) definition. CSS and OS were evaluated by chart review, death certificates, and referring physician follow-up notes. Gleason scoring was performed by general pathologists at a community hospital in Seattle. Time to biochemical failure (BF) was calculated and compared by Kaplan-Meier plots. Results: Fifteen-year BRFS for the entire cohort was 80.4%. BRFS by D'Amico risk group classification cohort analysis was 85.9%, 79.9%, and 62.2% for low, intermediate, and high-risk patients, respectively. Follow-up ranged from 3.6 to 18.4 years; median follow-up was 15.4 years for biochemically free of disease patients. Overall median follow-up was 11.7 years. The median time to BF in those who failed was 5.1 years. CSS was 84%. OS was 37.1%. Average age at time of treatment was 70 years. There was no significant difference in BRFS between low and intermediate risk groups. Conclusion: I{sup 125} monotherapy results in excellent 15-year BRFS and CSS, especially when taking into account the era of treatment effect.

  8. Development of ProCaRS Clinical Nomograms for Biochemical Failure-free Survival Following Either Low-Dose Rate Brachytherapy or Conventionally Fractionated External Beam Radiation Therapy for Localized Prostate Cancer

    PubMed Central

    Warner, Andrew; Pickles, Tom; Crook, Juanita; Martin, Andre-Guy; Souhami, Luis; Catton, Charles; Lukka, Himu

    2015-01-01

    Purpose: Although several clinical nomograms predictive of biochemical failure-free survival (BFFS) for localized prostate cancer exist in the medical literature, making valid comparisons can be challenging due to variable definitions of biochemical failure, the disparate distribution of prognostic factors, and received treatments in patient populations. The aim of this investigation was to develop and validate clinically-based nomograms for 5-year BFFS using the ASTRO II “Phoenix” definition for two patient cohorts receiving low-dose rate (LDR) brachytherapy or conventionally fractionated external beam radiation therapy (EBRT) from a large Canadian multi-institutional database. Methods and Materials: Patients were selected from the GUROC (Genitourinary Radiation Oncologists of Canada) Prostate Cancer Risk Stratification (ProCaRS) database if they received (1) LDR brachytherapy ≥ 144 Gy (n=4208) or (2) EBRT ≥ 70 Gy  (n=822). Multivariable Cox regression analysis for BFFS was performed separately for each cohort and used to generate clinical nomograms predictive of 5-year BFFS. Nomograms were validated using calibration plots of nomogram predicted probability versus observed probability via Kaplan-Meier estimates. Results: Patients receiving LDR brachytherapy had a mean age of 64 ± 7 years, a mean baseline PSA of 6.3 ± 3.0 ng/mL, 75% had a Gleason 6, and 15% had a Gleason 7, whereas patients receiving EBRT had a mean age of 70 ± 6 years, a mean baseline PSA of 11.6 ± 10.7 ng/mL, 30% had a Gleason 6, 55% had a Gleason 7, and 14% had a Gleason 8-10. Nomograms for 5-year BFFS included age, use and duration of androgen deprivation therapy (ADT), baseline PSA, T stage, and Gleason score for LDR brachytherapy and an ADT (months), baseline PSA, Gleason score, and biological effective dose (Gy) for EBRT. Conclusions: Clinical nomograms examining 5-year BFFS were developed for patients receiving either LDR brachytherapy or conventionally fractionated EBRT and

  9. Dosimetry analyses comparing high-dose-rate brachytherapy, administered as monotherapy for localized prostate cancer, with stereotactic body radiation therapy simulated using CyberKnife

    PubMed Central

    Fukuda, Shoichi; Seo, Yuji; Shiomi, Hiroya; Yamada, Yuji; Ogata, Toshiyuki; Morimoto, Masahiro; Konishi, Koji; Yoshioka, Yasuo; Ogawa, Kazuhiko

    2014-01-01

    The purpose of this study was to perform dosimetry analyses comparing high-dose-rate brachytherapy (HDR-BT) with simulated stereotactic body radiotherapy (SBRT). We selected six consecutive patients treated with HDR-BT monotherapy in 2010, and a CyberKnife SBRT plan was simulated for each patient using computed tomography images and the contouring set used in the HDR-BT plan for the actual treatment, but adding appropriate planning target volume (PTV) margins for SBRT. Then, dosimetric profiles for PTVs of the rectum, bladder and urethra were compared between the two modalities. The SBRT plan was more homogenous and provided lower dose concentration but better coverage for the PTV. The maximum doses in the rectum were higher in the HDR-BT plans. However, the HDR-BT plan provided a sharper dose fall-off around the PTV, resulting in a significant and considerable difference in volume sparing of the rectum with the appropriate PTV margins added for SBRT. While the rectum D5cm3 for HDR-BT and SBRT was 30.7 and 38.3 Gy (P < 0.01) and V40 was 16.3 and 20.8 cm3 (P < 0.01), respectively, SBRT was significantly superior in almost all dosimetric profiles for the bladder and urethra. These results suggest that SBRT as an alternative to HDR-BT in hypofractionated radiotherapy for prostate cancer might have an advantage for bladder and urethra dose sparing, but for the rectum only when proper PTV margins for SBRT are adopted. PMID:24957754

  10. Two-fraction high-dose-rate brachytherapy within a single day combined with external beam radiotherapy for prostate cancer: single institution experience and outcomes

    PubMed Central

    Liu, Junyang; Kaidu, Motoki; Sasamoto, Ryuta; Ayukawa, Fumio; Yamana, Nobuko; Sato, Hiraku; Tanaka, Kensuke; Kawaguchi, Gen; Ohta, Atsushi; Maruyama, Katsuya; Abe, Eisuke; Kasahara, Takashi; Nishiyama, Tsutomu; Tomita, Yoshihiko; Aoyama, Hidefumi

    2016-01-01

    We investigated the outcomes of treatment for patients with localized prostate cancer (PCa) treated with 3D conformal radiation therapy (3D-CRT) followed by two-fraction high-dose-rate brachytherapy within a single day (2-fr.-HDR-BT/day) at a single institution. A total of 156 consecutive Asian males (median age, 67 years) were enrolled. To compare our findings with those of other studies, we analyzed our results using the D'Amico classification, assigning the patients to low- (n =5; 3.2%), intermediate- (n =36; 23.1%) and high-risk (n =115; 73.7%) groups (Stage T3 PCa patients were classified as high-risk). One patient in the D'Amico low-risk group (20%), 13 intermediate-risk patients (36.1%) and 99 high-risk patients (86.1%) underwent androgen deprivation therapy. We administered a prescription dose of 39 Gy in 13 fractions of 3D-CRT combined with 18 Gy of HDR-BT in two 9-Gy fractions delivered within a single day. We did not distinguish between risk groups in determining the prescription dose. The median follow-up period was 38 months. Of the 156 patients, one died from primary disease and five died from other diseases. The 3-year overall survival (OS) rates were 100%, 100% and 93.7%, and the 3-year ‘biochemical no evidence of disease (bNED)’ rates were 100%, 100% and 96.9% for the D'Amico low-, intermediate- and high-risk groups, respectively. No patient developed ≥ Grade 3 early toxicity. The Grade 3 late genitourinary toxicity rate was 2.6%, and no ≥ Grade 3 late gastrointestinal toxicity occurred. The efficacy and safety of this study were satisfactory, and longer-term follow-up is necessary. PMID:26983988

  11. Comparison of Intraoperatively Built Custom Linked Seeds Versus Loose Seed Gun Applicator Technique Using Real-Time Intraoperative Planning for Permanent Prostate Brachytherapy

    SciTech Connect

    Zauls, A. Jason; Ashenafi, Michael S.; Onicescu, Georgiana; Clarke, Harry S.; Marshall, David T.

    2011-11-15

    Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively. Methods and Materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patientsunderwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia. Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% ({Delta}pD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the {Delta}pD90% was -8.1Gy and -12.8Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a {Delta}pD90% of -8.7Gy and -9.8Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in {Delta}pD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia. Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

  12. SU-D-210-07: The Dependence On Acoustic Velocity of Medium On the Needle Template and Electronic Grid Alignment in Ultrasound QA for Prostate Brachytherapy

    SciTech Connect

    Kapoor, P; Kapoor, R; Curran, B

    2015-06-15

    Purpose: To analyze the impact on acoustic velocity (AV) of two different media (water and milk) using the needle template/electronic grid alignment test. Water, easily available, makes a good material to test the alignment of the template and grid although water’s AV (1498 m/s at 25°C) is significantly different from tissue (1540 m/s). Milk, with an AV much closer (1548 m/s) to prostate tissue, may be a good substitute for water in ultrasound quality assurance testing. Methods: Tests were performed using a Hitachi ultrasound unit with a mechanical arrangement designed to position needles parallel to the transducer. In this work, two materials – distilled water and homogenized whole milk (AVs of 1498 and 1548 m/s at 25°C) were used in a phantom to test ultrasound needle/grid alignment. The images were obtained with both materials and analyzed for their placement accuracy. Results: The needle template/electronic grid alignment tests showed displacement errors between measured and calculated values. The measurements showed displacements of 2.3mm (water) and 0.4mm (milk), and 1.6mm (water) and 0.3mm (milk) at depths of 7cm and 5cm respectively from true needle positions. The calculated results showed a displacement of 2.36 mm (water); 0.435mm (milk), and 1.66mm (water) and 0.31mm (milk) at a depth of 7cm and 5cm respectively. The displacements in the X and Y directions were also calculated. At depths of 7cm and 5cm, the (ΔX,ΔY) displacements in water were (0.829mm, 2.21mm) and (0.273mm, 1.634mm) and for milk were (0.15mm, 0.44mm) and (0.05mm, 0.302mm) respectively. Conclusion: The measured and calculated values were in good agreement for all tests. They show that milk provides superior results when performing needle template and electronic grid alignment tests for ultrasound units used in prostate brachytherapy.

  13. High-Dose-Rate Brachytherapy as Monotherapy Delivered in Two Fractions Within One Day for Favorable/Intermediate-Risk Prostate Cancer: Preliminary Toxicity Data

    SciTech Connect

    Ghilezan, Michel; Martinez, Alvaro; Gustason, Gary; Krauss, Daniel; Antonucci, J. Vito; Chen, Peter; Fontanesi, James; Wallace, Michelle; Ye Hong; Casey, Alyse; Sebastian, Evelyn; Kim, Leonard; Limbacher, Amy

    2012-07-01

    Purpose: To report the toxicity profile of high-dose-rate (HDR)-brachytherapy (BT) as monotherapy in a Human Investigation Committee-approved study consisting of a single implant and two fractions (12 Gy Multiplication-Sign 2) for a total dose of 24 Gy, delivered within 1 day. The dose was subsequently increased to 27 Gy (13.5 Gy Multiplication-Sign 2) delivered in 1 day. We report the acute and early chronic genitourinary and gastrointestinal toxicity. Methods and Materials: A total of 173 patients were treated between December 2005 and July 2010. However, only the first 100 were part of the IRB-approved study and out of these, only 94 had a minimal follow-up of 6 months, representing the study population for this preliminary report. All patients had clinical Stage T2b or less (American Joint Committee on Cancer, 5th edition), Gleason score 6-7 (3+4), and prostate-specific antigen level of {<=}12 ng/mL. Ultrasound-guided HDR-BT with real-time dosimetry was used. The prescription dose was 24 Gy for the first 50 patients and 27 Gy thereafter. The dosimetric goals and constraints were the same for the two dose groups. Toxicity was scored using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3. The highest toxicity scores encountered at any point during follow-up are reported. Results: The median follow-up was 17 months (range, 6-40.5). Most patients had Grade 0-1 acute toxicity. The Grade 2 acute genitourinary toxicity was mainly frequency/urgency (13%), dysuria (5%), hematuria, and dribbling/hesitancy (2%). None of the patients required a Foley catheter at any time; however, 8% of the patients experienced transient Grade 1 diarrhea. No other acute gastrointestinal toxicities were found. The most common chronic toxicity was Grade 2 urinary frequency/urgency in 16% of patients followed by dysuria in 4% of patients; 2 patients had Grade 2 rectal bleeding and 1 had Grade 4, requiring laser treatment. Conclusions: Favorable

  14. Cardiovascular Comorbidity and Mortality in Men With Prostate Cancer Treated With Brachytherapy-Based Radiation With or Without Hormonal Therapy

    SciTech Connect

    Nanda, Akash; Chen, Ming-Hui; Moran, Brian J.; Braccioforte, Michelle H.; D'Amico, Anthony V.

    2013-04-01

    Purpose: To assess the impact of coronary artery disease (CAD) risk factors and sequelae on the risk of all-cause mortality (ACM) in men treated for prostate cancer (PC). Methods and Materials: The study cohort comprised 5077 men with PC consecutively treated with curative intent between 1997 and 2006 at the Chicago Prostate Cancer Center. Cox and Fine and Gray's competing risks regression multivariable analyses were performed, assessing whether cardiovascular comorbidity impacted the risk of ACM and PC-specific mortality, respectively, adjusting for CAD risk factors (diabetes mellitus, hypercholesterolemia, or hypertension) and sequelae (congestive heart failure or myocardial infarction), age, year and type of treatment, and known PC prognostic factors. Results: When compared with men with no comorbidity there was a significantly increased risk of ACM in men with congestive heart failure or myocardial infarction (adjusted hazard ratio [AHR] 1.96, P<.001) and in men with diabetes mellitus (AHR 1.60, P=.03) and hypertension (AHR 1.25, P=.04). In contrast, men with hypercholesterolemia had a similar risk of ACM (AHR 0.68, P=.17) when compared with men with no comorbidity. Other factors associated with a significantly increased risk of ACM included age (AHR 1.09, P<.001), prostate-specific antigen level (AHR 1.25, P=.008), and Gleason score 8-10 disease (AHR 1.71, P=.003). Cardiovascular comorbidity did not impact the risk of PC-specific mortality. Conclusions: In addition to age and unfavorable PC prognostic factors, select CAD risk factors and sequelae are associated with an increased risk of ACM in men treated for PC. These comorbidity prognostic factors predict time courses of mortality from competing causes, which may be factored into the decision-making process when considering management options for PC in a given individual.

  15. High-dose-rate brachytherapy and hypofractionated external beam radiotherapy combined with long-term hormonal therapy for high-risk and very high-risk prostate cancer: outcomes after 5-year follow-up

    PubMed Central

    Ishiyama, Hiromichi; Satoh, Takefumi; Kitano, Masashi; Tabata, Ken-ichi; Komori, Shouko; Ikeda, Masaomi; Soda, Itaru; Kurosaka, Shinji; Sekiguchi, Akane; Kimura, Masaki; Kawakami, Shogo; Iwamura, Masatsugu; Hayakawa, Kazushige

    2014-01-01

    The purpose of this study was to report the outcomes of high-dose-rate (HDR) brachytherapy and hypofractionated external beam radiotherapy (EBRT) combined with long-term androgen deprivation therapy (ADT) for National Comprehensive Cancer Network (NCCN) criteria-defined high-risk (HR) and very high-risk (VHR) prostate cancer. Data from 178 HR (n = 96, 54%) and VHR (n = 82, 46%) prostate cancer patients who underwent 192Ir-HDR brachytherapy and hypofractionated EBRT with long-term ADT between 2003 and 2008 were retrospectively analyzed. The mean dose to 90% of the planning target volume was 6.3 Gy/fraction of HDR brachytherapy. After five fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administered. All patients initially underwent ≥6 months of neoadjuvant ADT, and adjuvant ADT was continued for 36 months after EBRT. The median follow-up was 61 months (range, 25–94 months) from the start of radiotherapy. The 5-year biochemical non-evidence of disease, freedom from clinical failure and overall survival rates were 90.6% (HR, 97.8%; VHR, 81.9%), 95.2% (HR, 97.7%; VHR, 92.1%), and 96.9% (HR, 100%; VHR, 93.3%), respectively. The highest Radiation Therapy Oncology Group-defined late genitourinary toxicities were Grade 2 in 7.3% of patients and Grade 3 in 9.6%. The highest late gastrointestinal toxicities were Grade 2 in 2.8% of patients and Grade 3 in 0%. Although the 5-year outcome of this tri-modality approach seems favorable, further follow-up is necessary to validate clinical and survival advantages of this intensive approach compared with the standard EBRT approach. PMID:24222312

  16. Boost in radiotherapy: external beam sunset, brachytherapy sunrise

    PubMed Central

    2009-01-01

    Radiobiological limitations for dose escalation in external radiotherapy are presented. Biological and clinical concept of brachytherapy boost to increase treatment efficacy is discussed, and different methods are compared. Oncentra Prostate 3D conformal real-time ultrasound-guided brachytherapy is presented as a solution for boost or sole therapy.

  17. Single-Fraction High-Dose-Rate Brachytherapy and Hypofractionated External Beam Radiotherapy for Men With Intermediate-Risk Prostate Cancer: Analysis of Short- and Medium-Term Toxicity and Quality of Life

    SciTech Connect

    Morton, Gerard C.; Loblaw, D. Andrew; Sankreacha, Raxa

    2010-07-01

    Purpose: To determine the short- and medium-term effects of a single high-dose-rate brachytherapy fraction of 15Gy and hypofractionated external beam radiation therapy for prostate cancer. Methods and Materials: Eligible patients had localized prostate cancer with a Gleason score of 7 and a prostate-specific antigen (PSA) concentration of <20 ng/ml or a Gleason score of 6 with a PSA concentration of 10 to 20 ng/ml. Patients received high-dose-rate brachytherapy as a single 15-Gy dose, followed by external beam radiation therapy at 37.5Gy in 15 fractions, and were followed prospectively for toxicity (using Common Terminology Criteria for Adverse Events version 3.0), urinary symptoms (using the International Prostate Symptom Score [IPSS]), erectile function (with the International Index of Erectile Function [IIEF]), and health-related quality of life (with the Expanded Prostate Cancer Index Composite [EPIC]). Clinical examinations and PSA measurements were performed at every visit, and prostate biopsies were repeated at 2 years. The trial accrued 125 patients, with a median follow-up of 1.14 years. Results: Acute grade 2 and 3 genitourinary toxicity occurred in 62% and 1.6% of patients, respectively, and acute grade 2 gastrointestinal toxicity occurred in 6.5% of patients. No grade 3 late toxicity has occurred: 47% of patients had grade 2 genitourinary and 10% of patients had grade 2 gastrointestinal toxicity. Median IPSSs rose from 5 at baseline to 12 at 1 month and returned to 7 at 3 months. Of the total number of patients who were initially potent (IIEF, >21), 8% of patients developed mild to moderate dysfunction, and 27% of patients developed severe erectile dysfunction. Baseline EPIC bowel, urinary, and sexual bother scores decreased by 9, 7, and 19 points, respectively, at 1 year. No patient has experienced biochemical failure, and 16 of the first 17 biopsy results showed no malignancy. Conclusions: Treatment is well tolerated in the short and medium term, with

  18. AAPM recommendations on dose prescription and reporting methods for permanent interstitial brachytherapy for prostate cancer: Report of Task Group 137

    SciTech Connect

    Nath, Ravinder; Bice, William S.; Butler, Wayne M.; Chen Zhe; Meigooni, Ali S.; Narayana, Vrinda; Rivard, Mark J.; Yu Yan

    2009-11-15

    During the past decade, permanent radioactive source implantation of the prostate has become the standard of care for selected prostate cancer patients, and the techniques for implantation have evolved in many different forms. Although most implants use {sup 125}I or {sup 103}Pd sources, clinical use of {sup 131}Cs sources has also recently been introduced. These sources produce different dose distributions and irradiate the tumors at different dose rates. Ultrasound was used originally to guide the planning and implantation of sources in the tumor. More recently, CT and/or MR are used routinely in many clinics for dose evaluation and planning. Several investigators reported that the tumor volumes and target volumes delineated from ultrasound, CT, and MR can vary substantially because of the inherent differences in these imaging modalities. It has also been reported that these volumes depend critically on the time of imaging after the implant. Many clinics, in particular those using intraoperative implantation, perform imaging only on the day of the implant. Because the effects of edema caused by surgical trauma can vary from one patient to another and resolve at different rates, the timing of imaging for dosimetry evaluation can have a profound effect on the dose reported (to have been delivered), i.e., for the same implant (same dose delivered), CT at different timing can yield different doses reported. Also, many different loading patterns and margins around the tumor volumes have been used, and these may lead to variations in the dose delivered. In this report, the current literature on these issues is reviewed, and the impact of these issues on the radiobiological response is estimated. The radiobiological models for the biological equivalent dose (BED) are reviewed. Starting with the BED model for acute single doses, the models for fractionated doses, continuous low-dose-rate irradiation, and both homogeneous and inhomogeneous dose distributions, as well as

  19. Phase II Trial of Radiation Dose Escalation With Conformal External Beam Radiotherapy and High-Dose-Rate Brachytherapy Combined With Long-Term Androgen Suppression in Unfavorable Prostate Cancer: Feasibility Report

    SciTech Connect

    Valero, Jeanette; Cambeiro, Mauricio; Galan, Carlos; Teijeira, Mercedes; Romero, Pilar; Zudaire, Javier; Moreno, Marta; Ciervide, Raquel; Aristu, Jose Javier; Martinez-Monge, Rafael

    2010-02-01

    Purpose: To determine the feasibility of combined long-term luteinizing hormone-releasing hormone agonist-based androgen suppressive therapy (AST) and dose escalation with high-dose-rate (HDR) brachytherapy for high-risk (HRPC) or very-high-risk prostate cancer (VHRPC). Methods and Materials: Between January 2001 and October 2006, 134 patients (median age, 70 years) with either National Comprehensive Cancer Network criteria-defined HRPC (n = 47, 35.1%) or VHRPC (n = 87, 64.9%) were prospectively enrolled in this Phase II trial. Tumor characteristics included a median pretreatment prostate-specific antigen level of 14.6 ng/mL, a median clinical stage of T2c, and a median Gleason score of 7. Three-dimensional conformal radiotherapy (54 Gy in 30 fractions) was followed by HDR brachytherapy (19 Gy in 4 b.i.d. treatments). Androgen suppressive therapy started 0-3 months before three-dimensional conformal radiotherapy and continued for 2 years. Results: One implant was repositioned with a new procedure (0.7%). Five patients (3.7%) discontinued AST at a median of 13 months (range, 6-18 months) because of disease progression (n = 1), hot flashes (n = 2), fatigue (n = 1), and impotence (n = 1). After a median follow-up of 37.4 months (range, 24-90 months), the highest Radiation Therapy Oncology Group-defined late urinary toxicities were Grade 0 in 47.8%, Grade 1 in 38.1%, Grade 2 in 7.5%, and Grade 3 in 6.7% of patients. Maximal late gastrointestinal toxicities were Grade 0 in 73.1%, Grade 1 in 16.4%, Grade 2 in 7.5%, and Grade 3 in 2.9% of patients. There were no Grade 4 or 5 events. Conclusions: Intermediate-term results show that dose escalation with HDR brachytherapy combined with long-term AST is feasible and has a toxicity profile similar to that reported by previous HDR brachytherapy studies.

  20. Antitumor effects of 32P-chromic-poly (L-lactide) brachytherapy in nude mice with human prostate cancer

    PubMed Central

    SUN, LIUJING; ZHU, XISHAN; XU, LONGBAO; WANG, ZIZHENG; SHAO, GUOQIANG; ZHAO, JUN

    2013-01-01

    The aim of the present study was to investigate the antitumor effects and tissue distribution of 32P-chromic-poly (L-lactide) (32P-CP-PLLA) in nude mice with human prostate cancer. Tumor models were obtained by transplantation of PC-3M tumor cells into male BALB/c nude mice. Animals were randomly divided into control, 32P-chromic phosphate (32P-CP) colloid and 32P-CP-PLLA groups (all n=20). A series of indices were investigated, including apoptosis of tumor cells, rate of apoptosis, expression of caspase 3 and 8, biodistribution and intratumoral concentration of 32P-CP-PLLA, intensity of radioactivity, tumor volume and microvessel density (MVD). Highly concentrated radioactivity of 32P-CP-PLLA in the tumor mass was detected by single photon emission computed tomography (SPECT) scanning. The residual activities of the 32P-CP-PLLA and 32P-CP colloid groups were 3.02±0.32 and 1.76±0.31 MBq, respectively, on day 14 following treatment. The tumor inhibition rates were 67.24±3.55 and 55.92±7.65%, respectively (P<0.01). Necrotic changes, in conjunction with apoptosis, were observed in the treatment group. MVD values for the 32P-CP-PLLA and 32P-CP colloid groups were 28.24±10.07 and 36.15±11.06, respectively. 32P-CP-PLLA showed an excellent capacity for killing tumor cells, inducing apoptosis and inhibiting angiogenesis. PMID:24137391

  1. Single-fraction high-dose-rate brachytherapy using real-time transrectal ultrasound based planning in combination with external beam radiotherapy for prostate cancer: dosimetrics and early clinical results

    PubMed Central

    Lauche, Olivier; Delouya, Guila; Taussky, Daniel; Menard, Cynthia; Béliveau-Nadeau, Dominic; Hervieux, Yannick; Larouche, Renée

    2016-01-01

    Purpose To validate the feasibility of a single-fraction high-dose-rate brachytherapy (HDRBT) boost for prostate cancer using real-time transrectal ultrasound (TRUS) based planning. Material and methods From August 2012 to September 2015, 126 patients underwent a single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning. External beam radiation therapy (EBRT) (37.5 Gy/15 fractions, 44 Gy/22 fractions, or 45 Gy/25 fractions) was performed before (31%) or after (69%) HDRBT boost. Genito-urinary (GU) and gastro-intestinal (GI) toxicity were assessed 4 and 12 months after the end of combined treatment using the international prostate symptom score scale (IPSS) and the common terminology criteria for adverse events (CTCAE) v3.0. Results All dose-planning objectives were achieved in 90% of patients. Prostate D90 ≥ 105% and ≤ 115% was achieved in 99% of patients, prostate V150 ≤ 40% in 99%, prostate V200 < 11% in 96%, urethra D10 < 120% for 99%, urethra V125 = 0% in 100%, and rectal V75 < 1 cc in 93% of patients. Median IPSS score was 4 at baseline and did not change at 4 and 12 months after combined treatment. No patients developed ≥ grade 2 GI toxicity. With a median follow-up of 10 months, only two patients experienced biochemical failure. Among patients who didn't receive ADT, cumulative percentage of patients with PSA ≤ 1 ng/ml at 4 and 18 months was respectively 23% and 66%. Conclusions Single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning achieves consistently high dosimetry quality. In combination with EBRT, toxicity outcomes appear promising. A longer follow-up is needed to assess long-term outcome and toxicities. PMID:27257413

  2. High dose rate brachytherapy for oral cancer

    PubMed Central

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  3. Brachytherapy in pelvic malignancies: a review for radiologists.

    PubMed

    Vicens, Rafael A; Rodriguez, Joshua; Sheplan, Lawrence; Mayo, Cody; Mayo, Lauren; Jensen, Corey

    2015-10-01

    Brachytherapy, also known as sealed source or internal radiation therapy, involves placement of a radioactive source immediately adjacent to or within tumor, thus enabling delivery of a localized high dose of radiation. Compared with external beam radiation which must first pass through non-target tissues, brachytherapy results in less radiation dose to normal tissues. In the past decade, brachytherapy use has markedly increased, thus radiologists are encountering brachytherapy devices and their associated post-treatment changes to increasing degree. This review will present a variety of brachytherapy devices that radiologists may encounter during diagnostic pelvic imaging with a focus on prostate and gynecologic malignancies. The reader will become familiar with the function, correct position, and potential complications of brachytherapy devices in an effort to improve diagnostic reporting and communication with clinicians.

  4. Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma

    SciTech Connect

    Mishra, Kavita K.; Quivey, Jeanne M.; Daftari, Inder K.; Weinberg, Vivian; Cole, Tia B.; Patel, Kishan; Castro, Joseph R.; Phillips, Theodore L.; Char, Devron H.

    2015-06-01

    Purpose: Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. Methods and Materials: From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Results: Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (<2 mm) were excluded, CPT still resulted in significantly improved LC: 100% versus 90% at 5 years and 98% versus 86% at 12 years, respectively (log rank: P=.048). Enucleation rate was lower after CPT: 11% versus 22% at 5 years and 17% versus 37% at 12 years, respectively (log rank: P=.01). Using Cox regression model, likelihood ratio test, treatment was the most important predictor of LC (P=.0002) and eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Conclusions: Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma.

  5. Rectal Bleeding After High-Dose-Rate Brachytherapy Combined With Hypofractionated External-Beam Radiotherapy for Localized Prostate Cancer: The Relationship Between Dose-Volume Histogram Parameters and the Occurrence Rate

    SciTech Connect

    Okamoto, Masahiko; Ishikawa, Hitoshi; Ebara, Takeshi; Kato, Hiroyuki; Tamaki, Tomoaki; Akimoto, Tetsuo; Ito, Kazuto; Miyakubo, Mai; Yamamoto, Takumi; Suzuki, Kazuhiro; Takahashi, Takeo; Nakano, Takashi

    2012-02-01

    Purpose: To determine the predictive risk factors for Grade 2 or worse rectal bleeding after high-dose-rate brachytherapy (HDR-BT) combined with hypofractionated external-beam radiotherapy (EBRT) for prostate cancer using dose-volume histogram analysis. Methods and Materials: The records of 216 patients treated with HDR-BT combined with EBRT were analyzed. The treatment protocols for HDR-BT were 5 Gy Multiplication-Sign five times in 3 days or 7 Gy Multiplication-Sign three, 10.5 Gy Multiplication-Sign two, or 9 Gy Multiplication-Sign two in 2 days. The EBRT doses ranged from 45 to 51 Gy with a fractional dose of 3 Gy. Results: In 20 patients Grade 2 or worse rectal bleeding developed, and the cumulative incidence rate was 9% at 5 years. By converting the HDR-BT and EBRT radiation doses into biologic effective doses (BED), the BED{sub 3} at rectal volumes of 5% and 10% in the patients who experienced bleeding were significantly higher than those in the remaining 196 patients. Univariate analysis showed that a higher rectal BED{sub 3-5%} and the use of fewer needles in brachytherapy were correlated with the incidence of bleeding, but BED{sub 3-5%} was found to be the only significant factor on multivariate analysis. Conclusions: The radiation dose delivered to small rectal lesions as 5% is important for predicting Grade 2 or worse rectal bleeding after HDR-BT combined with EBRT for prostate cancer.

  6. External-Beam Radiation Therapy and High-Dose Rate Brachytherapy Combined With Long-Term Androgen Deprivation Therapy in High and Very High Prostate Cancer: Preliminary Data on Clinical Outcome

    SciTech Connect

    Martinez-Monge, Rafael; Moreno, Marta; Ciervide, Raquel; Cambeiro, Mauricio; Perez-Gracia, Jose Luis; Gil-Bazo, Ignacio; Gaztanaga, Miren; Arbea, Leire; Pascual, Ignacio; Aristu, Javier

    2012-03-01

    Purpose: To determine the feasibility of combined long-term androgen deprivation therapy (ADT) and dose escalation with high-dose-rate (HDR) brachytherapy. Methods and Materials: Between 2001 and 2007, 200 patients with high-risk prostate cancer (32.5%) or very high-risk prostate cancer (67.5%) were prospectively enrolled in this Phase II trial. Tumor characteristics included a median pretreatment prostate-specific antigen of 15.2 ng/mL, a clinical stage of T2c, and a Gleason score of 7. Treatment consisted of 54 Gy of external irradiation (three-dimensional conformal radiotherapy [3DCRT]) followed by 19 Gy of HDR brachytherapy in four twice-daily treatments. ADT started 0-3 months before 3DCRT and continued for 2 years. Results: One hundred and ninety patients (95%) received 2 years of ADT. After a median follow-up of 3.7 years (range, 2-9), late Grade {>=}2 urinary toxicity was observed in 18% of the patients and Grade {>=}3 was observed in 5%. Prior transurethral resection of the prostate (p = 0.013) and bladder D{sub 50} {>=}1.19 Gy (p = 0.014) were associated with increased Grade {>=}2 urinary complications; age {>=}70 (p = 0.05) was associated with Grade {>=}3 urinary complications. Late Grade {>=}2 gastrointestinal toxicity was observed in 9% of the patients and Grade {>=}3 in 1.5%. CTV size {>=}35.8 cc (p = 0.007) and D{sub 100} {>=}3.05 Gy (p = 0.01) were significant for increased Grade {>=}2 complications. The 5-year and 9-year biochemical relapse-free survival (nadir + 2) rates were 85.1% and 75.7%, respectively. Patients with Gleason score of 7-10 had a decreased biochemical relapse-free survival (p = 0.007). Conclusions: Intermediate-term results at the 5-year time point indicate a favorable outcome without an increase in the rate of late complications.

  7. The dosimetry of brachytherapy-induced erectile dysfunction

    SciTech Connect

    Merrick, Gregory S.; Butler, Wayne M

    2003-12-31

    There is emerging evidence that brachytherapy-induced erectile dysfunction (ED) is technique-related and may be minimized by careful attention to source placement. Herein, we review the relationship between radiation doses to the prostate gland/surrounding structures and the development of brachytherapy-induced ED. The permanent prostate brachytherapy literature was reviewed using MEDLINE searches to ensure completeness. Although the site-specific structure associated with brachytherapy-induced ED remains unknown, there is an increasing body of data implicating the proximal penis. With day 0 CT-based dosimetry, the dose to 50% (D{sub 50}) and 25% (D{sub 25}) of the bulb of the penis should be maintained below 40% and 60% mPD, respectively, while the crura D{sub 50} should be maintained below 28% mPD to maximize post-brachytherapy potency. To date, there is no data to suggest that either radiation doses to the neurovascular bundles or choice of isotope is associated with brachytherapy-induced ED, while conflicting data has been reported regarding radiation dose to the prostate and the use of supplemental external beam radiation therapy. Although the etiology of brachytherapy-induced ED is likely multifactorial, the available data supports the proximal penis as an important site-specific structure. Refinements in implant technique, including preplanning and intraoperative seed placement, will result in lower radiation doses to the proximal penis with potential improvement in potency preservation.

  8. Long-Term Outcomes for Patients with Prostate Cancer Having Intermediate and High-Risk Disease, Treated with Combination External Beam Irradiation and Brachytherapy

    PubMed Central

    Dattoli, Michael; Wallner, Kent; True, Lawrence; Bostwick, David; Cash, Jennifer; Sorace, Richard

    2010-01-01

    Background. Perception remains that brachytherapy-based regimens are inappropriate for patients having increased risk of extracapsular extension (ECE). Methods. 321 consecutive intermediate and high-risk disease patients were treated between 1/92 and 2/97 by one author (M. Dattoli) and stratified by NCCN guidelines. 157 had intermediate-risk; 164 had high-risk disease. All were treated using the combination EBRT/brachytherapy ± hormones. Biochemical failure was defined using PSA >0.2 and nadir +2 at last followup. Nonfailing patients followup was median 10.5 years. Both biochemical data and original biopsy slides were independently rereviewed at an outside institution. Results. Overall actuarial freedom from biochemical progression at 16 years was 82% (89% intermediate, 74% high-risk) with failure predictors: Gleason score (P = .01) and PSA (P = .03). Hormonal therapy did not affect failure rates (P = .14). Conclusion. This study helps to strengthen the rationale for brachytherapy-based regimens as being both durable and desirable treatment options for such patients. Prospective studies are justified to confirm these positive results. PMID:20847945

  9. Long-term outcomes for patients with prostate cancer having intermediate and high-risk disease, treated with combination external beam irradiation and brachytherapy.

    PubMed

    Dattoli, Michael; Wallner, Kent; True, Lawrence; Bostwick, David; Cash, Jennifer; Sorace, Richard

    2010-01-01

    Background. Perception remains that brachytherapy-based regimens are inappropriate for patients having increased risk of extracapsular extension (ECE). Methods. 321 consecutive intermediate and high-risk disease patients were treated between 1/92 and 2/97 by one author (M. Dattoli) and stratified by NCCN guidelines. 157 had intermediate-risk; 164 had high-risk disease. All were treated using the combination EBRT/brachytherapy ± hormones. Biochemical failure was defined using PSA >0.2 and nadir +2 at last followup. Nonfailing patients followup was median 10.5 years. Both biochemical data and original biopsy slides were independently rereviewed at an outside institution. Results. Overall actuarial freedom from biochemical progression at 16 years was 82% (89% intermediate, 74% high-risk) with failure predictors: Gleason score (P = .01) and PSA (P = .03). Hormonal therapy did not affect failure rates (P = .14). Conclusion. This study helps to strengthen the rationale for brachytherapy-based regimens as being both durable and desirable treatment options for such patients. Prospective studies are justified to confirm these positive results. PMID:20847945

  10. The impact of activating source dwell positions outside the CTV on the dose to treated normal tissue volumes in TRUS guided 3D conformal interstitial HDR brachytherapy of prostate cancer

    PubMed Central

    Thunberg, Per; Johansson, Bengt; Persliden, Jan

    2014-01-01

    Purpose Dose coverage is crucial for successful treatment in mono-brachytherapy. Since few and very high dose fractions are used, there is an important balance between dwell positioning outside the clinical target volume (CTV) and possible damage on adjacent normal tissue. The purpose of this study was to evaluate the possibility of having dwell positions close to the CTV surface, while maintaining an acceptable dose distribution, and to investigate the robustness in terms of known geometrical uncertainties of the implant. Material and methods This study included 37 patients who had received brachytherapy for prostate cancer as a monotherapy with the following schedules: 2 × 14 Gy or 3 × 11 Gy, each fraction separated by two weeks. The source dwell positions were activated 5 mm outside CTV. New optimizations were simulated for dwell positions at 3, 2, 1, and 0 mm. Inverse and graphical optimization were applied according to the relative dose constraints: V100 CTV ≥ 97%, Dmax, urethra ≤ 110%, and D10 rectal mucosa ≤ 65%. The V100, normal tissue outside CTV was used to evaluate dose variations caused by different dwell positions. Prostate geometries and dose distributions for the different dwell positions outside the CTV were used to investigate the impact on the CTV dose distribution due to geometrical uncertainties. Results Both V100, CTV, and V100, normal tissue decreased, 98.6% to 92.2%, and 17 cm3 to 9.0 cm3, for dwell activation from 5 mm to 0 mm. The evaluation of both simulated longitudinal geometrical uncertainties and different source dwell activations implied that V100, CTV ranged from 98.6% to 86.3%. Conclusions It is possible to reduce the V100, normal tissue by decreasing the source dwell positions outside the CTV from 5 to 3 mm, while maintaining dose constraints. In combination with the estimated geometrical uncertainties, however, the source dwell positions need to be 5 mm from the surface in order to maintain a robust implant. PMID:25337130

  11. Ultrasound use in gynecologic brachytherapy: Time to focus the beam.

    PubMed

    van Dyk, Sylvia; Schneider, Michal; Kondalsamy-Chennakesavan, Srinivas; Bernshaw, David; Narayan, Kailash

    2015-01-01

    There is wide disparity in the practice of brachytherapy for cervical cancer around the world. Although select well-resourced centers advocate use of MRI for all insertions, planar X-ray imaging remains the most commonly used imaging modality to assess intracavitary implants, particularly where the burden of cervical cancer is high. Incorporating soft tissue imaging into brachytherapy programs has been shown to improve the technical accuracy of implants, which in turn has led to improved local control and decreased toxicity. These improvements have a positive effect on the quality of life of patients undergoing brachytherapy for cervical cancer. Finding an accessible soft tissue imaging modality is essential to enable these improvements to be available to all patients. A modality that has good soft tissue imaging capabilities, is widely available, portable, and economical, is needed. Ultrasound fulfils these requirements and offers the potential of soft tissue image guidance to a much wider brachytherapy community. Although use of ultrasound is the standard of care in brachytherapy for prostate cancer, it only seems to have limited uptake in gynecologic brachytherapy. This article reviews the role of ultrasound in gynecologic brachytherapy and highlights the potential applications for use in brachytherapy for cervical cancer.

  12. Correlation between treatment plan parameters and particular prognostic factors in prostate cancer treated with high–dose–rate brachytherapy (HDR–BT) as a boost

    PubMed Central

    Kanikowski, Marek; Skowronek, Janusz; Dymnicka, Magdalena; Piotrowski, Tomasz

    2009-01-01

    Purpose Certain constraints for target coverage and dose limits in Organs at Risk (OARs) shows some evidence that doses values and homogeneity index in treated volume depends on prognostic factors such as prostate volume, location of urethra and the number of inserted applicators. Our study is to determine the relation between values of the doses in prostate, OARs and particular prognostic factors related to HDR-BT of prostate cancer. Material and methods The amount of 190 patients with localized prostate cancer were treated with interstitial HDR-BT between July 2006 and July 2007. The HDR-BT was administered as a boost for previously delivered 50 Gy dose from external beam radiotherapy. Dose volume parameters were determined such as: Dmin, Dmax, Dmean, D90, V100, V150 and V200 for prostate and Dmin, Dmax, Dmean, D10 and V100 for urethra and rectum (OARs), respectively. These parameters were correlated with prognostic factors such as: age, staging (TNM), Gleason score, initial PSA level (i-PSA), number of needles and volume of the prostate. Results The mean value of D90 was 91.3%, range 65.9-102.8%. Mean urethral D10 was 121, 8%, range 78.8-152.9%. Mean rectal D10 was 81.3%, range 37.4-101.0%. Statistically significant relationship was found between staging (TNM), prostate volume, and the number of needles used for implant and increased prostate D90 and decreased V200. The prognostic factor was only the age which was related to increased urethral D10 and Dmax. No correlation was found between any prognostic factor and rectal wall DVH parameters. Conclusions Increased prostate volume with improved D90 and greater number of implanted needles results in better target coverage (higher V100), better dose distribution (lower V200) and decreased dose delivered to the urethra (lower urethral D10, Dmax), with no evident influence on rectal wall. Further investigation with closed follow-up should give an answer whether the above corresponds with morbidity and outcome.

  13. Dosimetric Considerations to Determine the Optimal Technique for Localized Prostate Cancer Among External Photon, Proton, or Carbon-Ion Therapy and High-Dose-Rate or Low-Dose-Rate Brachytherapy

    SciTech Connect

    Georg, Dietmar

    2014-03-01

    Purpose: To assess the dosimetric differences among volumetric modulated arc therapy (VMAT), scanned proton therapy (intensity-modulated proton therapy, IMPT), scanned carbon-ion therapy (intensity-modulated carbon-ion therapy, IMIT), and low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy (BT) treatment of localized prostate cancer. Methods and Materials: Ten patients were considered for this planning study. For external beam radiation therapy (EBRT), planning target volume was created by adding a margin of 5 mm (lateral/anterior–posterior) and 8 mm (superior–inferior) to the clinical target volume. Bladder wall (BW), rectal wall (RW), femoral heads, urethra, and pelvic tissue were considered as organs at risk. For VMAT and IMPT, 78 Gy(relative biological effectiveness, RBE)/2 Gy were prescribed. The IMIT was based on 66 Gy(RBE)/20 fractions. The clinical target volume planning aims for HDR-BT ({sup 192}Ir) and LDR-BT ({sup 125}I) were D{sub 90%} ≥34 Gy in 8.5 Gy per fraction and D{sub 90%} ≥145 Gy. Both physical and RBE-weighted dose distributions for protons and carbon-ions were converted to dose distributions based on 2-Gy(IsoE) fractions. From these dose distributions various dose and dose–volume parameters were extracted. Results: Rectal wall exposure 30-70 Gy(IsoE) was reduced for IMIT, LDR-BT, and HDR-BT when compared with VMAT and IMPT. The high-dose region of the BW dose–volume histogram above 50 Gy(IsoE) of IMPT resembled the VMAT shape, whereas all other techniques showed a significantly lower high-dose region. For all 3 EBRT techniques similar urethra D{sub mean} around 74 Gy(IsoE) were obtained. The LDR-BT results were approximately 30 Gy(IsoE) higher, HDR-BT 10 Gy(IsoE) lower. Normal tissue and femoral head sparing was best with BT. Conclusion: Despite the different EBRT prescription and fractionation schemes, the high-dose regions of BW and RW expressed in Gy(IsoE) were on the same order of magnitude. Brachytherapy techniques

  14. Interstitially implanted I125 for prostate cancer using transrectal ultrasound

    SciTech Connect

    Greenburg, S.; Petersen, J.; Hansen-Peters, I.; Baylinson, W. )

    1990-11-01

    Prostate cancer is the third leading cause of death from cancer among men in the United States. Traditional treatments for prostate cancer are prostatectomy, external beam irradiation, and interstitial implantation of Iodine125 (I125) via laparotomy. These treatments are associated with significant morbidity and limitations. Based on experience with I125 interstitial implantation by transrectal ultrasound guidance for early-stage prostate cancer, it seems that this newer method of treatment has greater accuracy of placement and distribution of the isotope and has had few reported complications. The need for a surgical incision has been eliminated. Hospitalization time also has been decreased, creating the need for ambulatory and inpatient nurses to understand the importance of their respective roles in providing coordinated quality care for these patients. Nurses in these departments must have knowledge of the procedure, radiation safety, and common side effects related to the implant.

  15. Coregistered photoacoustic-ultrasound imaging applied to brachytherapy

    NASA Astrophysics Data System (ADS)

    Harrison, Tyler; Zemp, Roger J.

    2011-08-01

    Brachytherapy is a form of radiation therapy commonly used in the treatment of prostate cancer wherein sustained radiation doses can be precisely targeted to the tumor area by the implantation of small radioactive seeds around the treatment area. Ultrasound is a popular imaging mode for seed implantation, but the seeds are difficult to distinguish from the tissue structure. In this work, we demonstrate the feasibility of photoacoustic imaging for identifying brachytherapy seeds in a tissue phantom, comparing the received intensity to endogenous contrast. We have found that photoacoustic imaging at 1064 nm can identify brachytherapy seeds uniquely at laser penetration depths of 5 cm in biological tissue at the ANSI limit for human exposure with a contrast-to-noise ratio of 26.5 dB. Our realtime combined photoacoustic-ultrasound imaging approach may be suitable for brachytherapy seed placement and post-placement verification, potentially allowing for realtime dosimetry assessment during implantation.

  16. Design and optimization of a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, Michael A.

    Trans-rectal ultrasound guided (TRUS) low dose rate (LDR) interstitial brachytherapy has become a popular procedure for the treatment of prostate cancer, the most common type of non-skin cancer among men. The current TRUS technique of LDR implantation may result in less than ideal coverage of the tumor with increased risk of negative response such as rectal toxicity and urinary retention. This technique is limited by the skill of the physician performing the implant, the accuracy of needle localization, and the inherent weaknesses of the procedure itself. The treatment may require 100 or more sources and 25 needles, compounding the inaccuracy of the needle localization procedure. A robot designed for prostate brachytherapy may increase the accuracy of needle placement while minimizing the effect of physician technique in the TRUS procedure. Furthermore, a robot may improve associated toxicities by utilizing angled insertions and freeing implantations from constraints applied by the 0.5 cm-spaced template used in the TRUS method. Within our group, Lin et al. have designed a new type of LDR source. The "directional" source is a seed designed to be partially shielded. Thus, a directional, or anisotropic, source does not emit radiation in all directions. The source can be oriented to irradiate cancerous tissues while sparing normal ones. This type of source necessitates a new, highly accurate method for localization in 6 degrees of freedom. A robot is the best way to accomplish this task accurately. The following presentation of work describes the invention and optimization of a new prostate brachytherapy robot that fulfills these goals. Furthermore, some research has been dedicated to the use of the robot to perform needle insertion tasks (brachytherapy, biopsy, RF ablation, etc.) in nearly any other soft tissue in the body. This can be accomplished with the robot combined with automatic, magnetic tracking.

  17. Stereotactic interstitial brachytherapy of malignant astrocytomas with remarks on postimplantation computed tomographic appearance

    SciTech Connect

    Willis, B.K.; Heilbrun, M.P.; Sapozink, M.D.; McDonald, P.R.

    1988-09-01

    Seventeen patients were treated with stereotactically implanted high activity iodine-125 seeds, 12 patients for recurrent malignant astrocytomas (Protocol I) and 5 patients for newly diagnosed glioblastomas (Protocol II). Total radiation dosage to the recurrent tumors in Protocol I, including prior external beam irradiation, averaged 13,500 cGy. In the follow-up period of 6 to 50 months, the survival rate was 93% at 6 months, 60% at 12 months, 50% at 18 months, and 38% at 24 months after implantation. In Protocol II, brachytherapy was used as an interstitial radiation boost to the conventional treatment of newly diagnosed glioblastomas. External beam therapy and interstitial brachytherapy provided 11,000 cGy to these tumors. In the follow-up period of 15 to 27 months, there was a 100% survival at 12 months, 75% at 18 months, and 25% at 24 months after implantation. Eight of our 17 patients required reoperation for persistent or recurrent mass lesions at 6 to 15 months postimplantation; 7 were found to harbor masses of radionecrosis containing nests of anaplastic astrocytes; 1 had frank tumor recurrence. Median survival in this group of patients requiring reoperation was 18.7 months postimplantation. In a review of postimplantation computed tomographic scans, significant mass effect and crossover of hypodensity or enhancement into the corpus callosum or opposite hemisphere were found to have prognostic significance; persistent areas of contrast enhancement and excessive peritumoral hypodensity did not.

  18. Improving photoacoustic imaging contrast of brachytherapy seeds

    NASA Astrophysics Data System (ADS)

    Pan, Leo; Baghani, Ali; Rohling, Robert; Abolmaesumi, Purang; Salcudean, Septimiu; Tang, Shuo

    2013-03-01

    Prostate brachytherapy is a form of radiotherapy for treating prostate cancer where the radiation sources are seeds inserted into the prostate. Accurate localization of seeds during prostate brachytherapy is essential to the success of intraoperative treatment planning. The current standard modality used in intraoperative seeds localization is transrectal ultrasound. Transrectal ultrasound, however, suffers in image quality due to several factors such speckle, shadowing, and off-axis seed orientation. Photoacoustic imaging, based on the photoacoustic phenomenon, is an emerging imaging modality. The contrast generating mechanism in photoacoustic imaging is optical absorption that is fundamentally different from conventional B-mode ultrasound which depicts changes in acoustic impedance. A photoacoustic imaging system is developed using a commercial ultrasound system. To improve imaging contrast and depth penetration, absorption enhancing coating is applied to the seeds. In comparison to bare seeds, approximately 18.5 dB increase in signal-to-noise ratio as well as a doubling of imaging depth are achieved. Our results demonstrate that the coating of the seeds can further improve the discernibility of the seeds.

  19. SU-F-19A-07: Is a Day30 Scan Necessary to Evaluate Activity-Based Regulatory Compliance in Permanent Interstitial Brachytherapy for Prostate Cancer?

    SciTech Connect

    Kapur, P; Ford, J; Moghanaki, D; Datsang, R; Chang, M; Rosu, M; Hagan, M; Palta, J

    2014-06-15

    Purpose: To evaluate the Medical Event (ME) criteria for I-125 prostate implants based on the assessment of post implant dosimetry on “Day0”/“Day30” imaging. The new ME criteria do not mandate a timeframe for this assessment. The compliance criteria are: more than 80% of the activity from the written directive for treatment site (TS) must be implanted inside TS, and doses to 1cc of either uninvolved rectum (D1-UR) or uninvolved bladder (D1-UB), or 2cc of other non-specified tissue (D2-UT) must be less than 150% of the planned dose. Methods: “Day0”/“Day30” post-implant analyses for 25 patients were evaluated. Treatment plans had a peripheral loading pattern with 2 core needles placed at least 10 mm away from urethra, with several seeds planned outside of the prostate for adequate target coverage. TS were a uniform 5 mm expansion of the prostate, except posteriorly (no expansion). Results: “Day0”/“Day30”analyses found no MEs. The relative changes for D1-UR, D1-UB, and D2-UT were (ranges): [−37.0, 38.2]%, [−96.5, 74.7]%, and [−41.2, 37.7]%. Furthermore, changes did not correlate with prostate volume changes of −18.7% [σ:16.0%, range:−60.5%, +6.4%]. These unfavorable changes did not lead to ME at “Day30” because these values were generally well below 150% at “Day0”. However, D2-UT dose values exceeded those for D1-UR and D1-UB at both “Day0”/“Day30”. Conclusion: The total activity was relatively insensitive to changes in target volume from “Day0” to ”Day30”. The dose metrics of interest, albeit susceptible to large, often unfavorable changes, remained less than the 150% threshold. Data from this study suggest that “Day0” can be used for the regulatory compliance evaluation. However, further evaluation at “Day30” is advisable if D2-UT is 110% or above (based on the largest D2-UT increase of 37.7% observed in this patient population). Future rigorous statistical analysis of a larger cohort will afford a

  20. Concurrent versus sequential application of ferromagnetic hyperthermia and 125I brachytherapy of melanoma in an animal model.

    PubMed Central

    Mieler, W F

    1997-01-01

    OBJECTIVE: To determine the efficacy of concurrent versus sequential ferromagnetic hyperthermia (FMH), combined with Iodine-125 (125I) brachytherapy, in the treatment of uveal melanoma in a rabbit model. MATERIALS AND METHODS: A Greene melanoma cell line was implanted in rabbit eyes to establish a tumor model comparable to a uveal melanoma. Seventy-one tumor-containing rabbit eyes were treated with 125I brachytherapy at 20, 25, 35, 45, or 55 Gray (Gy)(38 eyes), and with either concurrent (15 eyes) or sequential (18 eyes) FMH, delivered at 48.2 degrees C for 1 hour. An additional 13 eyes were treated with FMH alone at 48.2 degrees C, either in a single heat application (5 eyes), or in a repetitive mode (8 eyes). The radiation and heat were delivered via an episcleral plaque. All tumors were followed with indirect ophthalmoscopy and echography. RESULTS: Tumors treated with 125I brachytherapy alone exhibited complete tumor regression in 50% of eyes at 42 Gy with none of the tumors responding to less than 35 Gy. FMH alone at 48.2 degrees C applied in one cycle limited tumor growth in 20% of eyes, while all eyes treated with repetitive heating exhibited complete tumor control. With concurrent application of FMH and 125I, the 50% tumor control rate occurred at 9.5 Gy, thus resulting in a thermal enhancement ratio (TER) of 4.4. With sequential treatment, the 50% tumor control rate was at 30 Gy, with a resultant TER of 1.4. No complications related to 125I brachytherapy were noted in any eyes, while transient retinal whitening was seen with the FMH. CONCLUSION: This study documents the enhanced synergistic interaction of concurrent FMH and 125I brachytherapy, compared to sequential treatment, in this rabbit melanoma model. PMID:9440189

  1. WE-F-BRD-01: HDR Brachytherapy II: Integrating Imaging with HDR

    SciTech Connect

    Craciunescu, O; Todor, D; Leeuw, A de

    2014-06-15

    In recent years, with the advent of high/pulsed dose rate afterloading technology, advanced treatment planning systems, CT/MRI compatible applicators, and advanced imaging platforms, image-guided adaptive brachytherapy treatments (IGABT) have started to play an ever increasing role in modern radiation therapy. The most accurate way to approach IGABT treatment is to provide the infrastructure that combines in a single setting an appropriate imaging device, a treatment planning system, and a treatment unit. The Brachytherapy Suite is not a new concept, yet the modern suites are incorporating state-of-the-art imaging (MRI, CBCT equipped simulators, CT, and /or US) that require correct integration with each other and with the treatment planning and delivery systems. Arguably, an MRI-equipped Brachytherapy Suite is the ideal setup for real-time adaptive brachytherapy treatments. The main impediment to MRI-IGABT adoption is access to MRI scanners. Very few radiation oncology departments currently house MRI scanners, and even fewer in a dedicated Brachytherapy Suite. CBCT equipped simulators are increasingly offered by manufacturers as part of a Brachytherapy Suite installation. If optimized, images acquired can be used for treatment planning, or can be registered with other imaging modalities. This infrastructure is relevant for all forms of brachytherapy, especially those utilizing multi-fractionated courses of treatment such as prostate and cervix. Moreover, for prostate brachytherapy, US imaging systems can be part of the suite to allow for real-time HDR/LDR treatments. Learning Objectives: Understand the adaptive workflow of MR-based IGBT for cervical cancer. Familiarize with commissioning aspects of a CBCT equipped simulator with emphasis on brachytherapy applications Learn about the current status and future developments in US-based prostate brachytherapy.

  2. Prostate biopsy

    MedlinePlus

    ... prostate biopsy; Fine needle biopsy of the prostate; Core biopsy of the prostate; Targeted prostate biopsy; Prostate biopsy - transrectal ultrasound (TRUS); Stereotactic transperineal prostate biopsy (STPB)

  3. Comparison of Prophylactic Naftopidil, Tamsulosin, and Silodosin for {sup 125}I Brachytherapy-Induced Lower Urinary Tract Symptoms in Patients With Prostate Cancer: Randomized Controlled Trial

    SciTech Connect

    Tsumura, Hideyasu; Satoh, Takefumi; Ishiyama, Hiromichi; Tabata, Ken-ichi; Kotani, Shouko; Minamida, Satoru; Kimura, Masaki; Fujita, Tetsuo; Matsumoto, Kazumasa; Kitano, Masashi; Hayakawa, Kazushige; Baba, Shiro

    2011-11-15

    Purpose: To compare the efficacy of three {alpha}{sub 1A}/{alpha}{sub 1D}-adrenoceptor (AR) antagonists-naftopidil, tamsulosin, and silodosin-that have differing affinities for the {alpha}{sub 1}-AR subtypes in treating urinary morbidities in Japanese men with {sup 125}I prostate implantation (PI) for prostate cancer. Methods and Materials: This single-institution prospective randomized controlled trial compared naftopidil, tamsulosin, and silodosin in patients undergoing PI. Patients were randomized and received either naftopidil, tamsulosin, or silodosin. Treatment began 1 day after PI and continued for 1 year. The primary efficacy variables were the changes in total International Prostate Symptom Score (IPSS) and postvoid residual urine (PVR). The secondary efficacy variables were changes in IPSS storage score and IPSS voiding score from baseline to set points during the study (1, 3, 6, and 12 months). Results: Two hundred twelve patients were evaluated in this study between June 2006 and February 2009: 71, 70, and 71 patients in the naftopidil, tamsulosin, and silodosin groups, respectively. With respect to the primary efficacy variables, the mean changes in the total IPSS at 1 month after PI in the naftopidil, tamsulosin, and silodosin groups were +10.3, +8.9, and +7.5, respectively. There were significantly greater decreases with silodosin than naftopidil at 1 month in the total IPSS. The mean changes in the PVR at 6 months were +14.6, +23.7, and +5.7 mL in the naftopidil, tamsulosin, and silodosin groups, respectively; silodosin showed a significant improvement in the PVR at 6 months vs. tamsulosin. With respect to the secondary efficacy variables, the mean changes in the IPSS voiding score at 1 month in the naftopidil, tamsulosin, and silodosin groups were +6.5, +5.6, and +4.5, respectively; silodosin showed a significant improvement in the IPSS voiding score at 1 month vs. naftopidil. Conclusions: Silodosin has a greater impact on improving PI

  4. Cryosurgery for prostate cancer.

    PubMed

    Fahmy, W E; Bissada, N K

    2003-01-01

    Choice of management for patients with prostate cancer is influenced by patient and disease characteristics and life expectancy. Management options include expectance (watchful waiting), radical prostatectomy, external beam radiotherapy, brachytherapy, and cryosurgical ablation of the prostate (CSAP). The role of cryotherapy in the management of prostate cancer is still evolving. Continued research has allowed the introduction of efficient and safe cryosurgical equipment exemplified by the current third-generation cryosurgical machines. CSAP can be performed in an ambulatory surgery setting or as inpatient surgery with overnight stay. The procedure is performed under continuous ultrasonic monitoring. Mature data from the use of second-generation cryosurgical equipment indicate that CSAP is an effective therapeutic modality for managing patients with prostate cancer. Current data with the third-generation cryosurgical equipment are not mature. However, the favorable side effect profile and the good early responses seem to indicate that this modality will have a prominent role in the management of patients with prostate cancer.

  5. Brachytherapy needle deflection evaluation and correction

    SciTech Connect

    Wan Gang; Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2005-04-01

    In prostate brachytherapy, an 18-gauge needle is used to implant radioactive seeds. This thin needle can be deflected from the preplanned trajectory in the prostate, potentially resulting in a suboptimum dose pattern and at times requiring repeated needle insertion to achieve optimal dosimetry. In this paper, we report on the evaluation of brachytherapy needle deflection and bending in test phantoms and two approaches to overcome the problem. First we tested the relationship between needle deflection and insertion depth as well as whether needle bending occurred. Targeting accuracy was tested by inserting a brachytherapy needle to target 16 points in chicken tissue phantoms. By implanting dummy seeds into chicken tissue phantoms under 3D ultrasound guidance, the overall accuracy of seed implantation was determined. We evaluated methods to overcome brachytherapy needle deflection with three different insertion methods: constant orientation, constant rotation, and orientation reversal at half of the insertion depth. Our results showed that needle deflection is linear with needle insertion depth, and that no noticeable bending occurs with needle insertion into the tissue and agar phantoms. A 3D principal component analysis was performed to obtain the population distribution of needle tip and seed position relative to the target positions. Our results showed that with the constant orientation insertion method, the mean needle targeting error was 2.8 mm and the mean seed implantation error was 2.9 mm. Using the constant rotation and orientation reversal at half insertion depth methods, the deflection error was reduced. The mean needle targeting errors were 0.8 and 1.2 mm for the constant rotation and orientation reversal methods, respectively, and the seed implantation errors were 0.9 and 1.5 mm for constant rotation insertion and orientation reversal methods, respectively.

  6. NOTE: On the question of 3D seed reconstruction in prostate brachytherapy: the determination of x-ray source and film locations

    NASA Astrophysics Data System (ADS)

    Zhang, Mutian; Zaider, Marco; Worman, Michael; Cohen, Gilad

    2004-10-01

    Inaccuracy in seed placement during permanent prostate implants may lead to significant dosimetric deviations from the intended plan. In two recent publications (Todor et al 2002 Phys. Med. Biol. 47 2031 48, Todor et al 2003 Phys. Med. Biol. 48 1153 71), methodology was described for identifying intraoperatively the positions of seeds already implanted, thus allowing re-optimization of the treatment plan and correcting for such seed misplacement. Seed reconstruction is performed using fluoroscopic images and an important (and non-trivial) component of this approach is the ability to accurately determine the position of the gantry relative to the treatment volume. We describe the methodology for acquiring this information, based on the known geometry of six markers attached to the ultrasound probe. This method does not require the C-arm unit to be isocentric and films can be taken with the gantry set at any arbitrary position. This is significant because the patient positioning on the operating table (in the lithotomy position) restricts the range of angles at which films can be taken to a quite narrow (typically ±10°) interval and, as a general rule, the closer the angles the larger the uncertainty in the seed location reconstruction along the direction from the x-ray source to the film.

  7. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    PubMed

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-01

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  8. Quantitative analysis of tissue distribution of the B16BL6-derived exosomes using a streptavidin-lactadherin fusion protein and iodine-125-labeled biotin derivative after intravenous injection in mice.

    PubMed

    Morishita, Masaki; Takahashi, Yuki; Nishikawa, Makiya; Sano, Kohei; Kato, Kana; Yamashita, Takuma; Imai, Takafumi; Saji, Hideo; Takakura, Yoshinobu

    2015-02-01

    We previously succeeded in the visualization of tissue distribution of B16BL6 cells-derived exosomes by labeling with Gaussia luciferase (gLuc)-LA, a fusion protein of gLuc (a reporter protein) and lactadherin (LA; an exosome-tropic protein). However, total amount of B16BL6-derived exosomes delivered to each organ could not be evaluated because of the reduction of luminescent signal from gLuc-LA. The aim of the present study was to quantitatively evaluate the tissue distribution of B16BL6-derived exosomes. To this end, we labeled B16BL6-derived exosomes with iodine-125 ((125) I) based on streptavidin (SAV)-biotin system. A plasmid vector encoding fusion protein, SAV-LA, was constructed, and B16BL6 cells were transfected with the plasmid to obtain SAV-LA-coupled exosomes. SAV-LA-coupled exosomes were incubated with (3-(125) I-iodobenzoyl) norbiotinamide ((125) I-IBB) to obtain (125) I-labeled B16BL6 exosomes. After intravenous injection of (125) I-labeled B16BL6 exosomes into mice, radioactivity quickly disappeared from the blood circulation. At 4 h, 28%, 1.6%, and 7% of the injected radioactivity/organ was detected in the liver, spleen, and lung, respectively. These results indicate that (125) I-labeling of exosomes using SAV-biotin system is a useful method to quantitatively evaluate the amount of exogenously administered exosomes delivered to each organ and that the liver is the major organ in the clearance of exogenously administered B16BL6-derived exosomes. PMID:25393546

  9. ³²P-chromic phosphate-Poly(L-Lactide) seeds of sustained release and their brachytherapy for prostate cancer with lymphatic metastasis.

    PubMed

    He, Xingjun; Jia, Ruipeng; Xu, Luwei; Liang, Kai; Wang, Zizheng; Shao, Guoqiang; Huang, Peilin; Li, Wencheng

    2012-09-01

    This study aims to develop a new agent, the ³²P-chromic phosphate-poly(l-lactide) (³²P-CP-PLLA) seed and to explore its anticancer effect against prostate cancer (Pca) with local lymphatic metastasis in nude mice. ³²P-CP-PLLA seeds of sustained release and nude mouse models of Pca with lymphatic metastasis were prepared. After 4 weeks, the tumor nude mouse models were randomly assigned into five groups. ³²P-CP-PLLA seeds (3.7, 7.4, 14.8, and 0 MBq) and ³²P-CP (14.8 MBq) were implanted in the tumor tissues of the nude mouse models. The following were discussed in this study: (1) the distributions of ³²P-CP-PLLA, (2) the pathological and morphological changes in the tumor and regional lymph nodes, and (3) the changes in white blood cell (WBC) and platelet counts in peripheral blood for toxic reactions. The homemade ³²P-CP-PLLA seed was a regular green cylinder, with an even distribution of mass and radioactivity. After implantation, single-photon emission computed tomograph (SPECT) showed that ³²P was mainly gathered in the tumor and regional lymph nodes. Morphological examinations revealed that necrosis and hemorrhage were around the tumor and focal lymph nodes. The tumor inhibition rates of the five groups were 70.16% ± 5.48%, 80.18% ± 5.84%, 84.97% ± 4.79%, (-), and 78.81% ± 3.13%, respectively. These values were all positive when compared with the control group. As a new homemade agent of pure β-ray, local implantation of the agent increased the focal retention of radioactivity at the target. Moreover, effective half-life showed an obvious damage to the tumor and metastatic foci of Pca.

  10. Assessing quality of life in long-term survivors after ¹²⁵I brachytherapy for low-grade glioma in childhood.

    PubMed

    Korinthenberg, R; Neuburger, D; Nikkhah, G; Teske, C; Schnabel, K; Calaminus, G

    2011-06-01

    Quality of life (QOL) is important for the survivors of malignancies. We investigated health-related QOL in 51 patients treated with iodine-125 (¹²⁵I) brachytherapy for childhood low-grade gliomas. Instruments included a questionnaire on life situation, German versions of PEDQOL (8-18 years), EORTC QLQ-30 and head and neck module H&N-35 (>18 years), strength and difficulties questionnaire, "Fertigkeitsskala Münster Heidelberg", and an adapted Rankin score. The time lapsed since ¹²⁵I-brachytherapy was 134 months (median, range: 29-293 months). 57% of the patients were over 18 years of age, 34% were 11-17 years old and 8% were younger. 14 had undergone other treatments after ¹²⁵I brachytherapy. Over half of the >18 year olds reported residual problems; 68% were disabled, 38% to a severe degree. Many of the young adults still lived with their parents and 17% were jobless. 43% of the children/adolescents needed rehabilitative treatment, 20% visited special schools and 71% were disabled, 33% severely. The patients and their caregivers rated their QOL as not different from that of the normal population. However, many QOL dimensions correlated to the severity of disability. Comparison of QOL outcomes between different treatment measures would require a prospective study controlling for the most important factors of influence.

  11. SU-E-J-214: MR Protocol Development to Visualize Sirius MRI Markers in Prostate Brachytherapy Patients for MR-Based Post-Implant Dosimetry

    SciTech Connect

    Lim, T; Wang, J; Frank, S; Stafford, R; Bruno, T; Bathala, T; Mahmood, U; Pugh, T; Ibbott, G; Kudchadker, R

    2015-06-15

    Purpose: The current CT-based post-implant dosimetry allows precise seed localization but limited anatomical delineation. Switching to MR-based post-implant dosimetry is confounded by imprecise seed localization. One approach is to place positive-contrast markers (Sirius) adjacent to the negative-contrast seeds. This patient study aims to assess the utility of a 3D fast spoiled gradient-recalled echo (FSPGR) sequence to visualize Sirius markers for post-implant dosimetry. Methods: MRI images were acquired in prostate implant patients (n=10) on Day 0 (day-of-implant) and Day 30. The post-implant MR protocol consisted of 3D T2-weighted fast-spin-echo (FSE), T2-weighted 2D-FSE (axial) and T1-weighted 2D-FSE (axial/sagittal/coronal). We incorporated a 3D-FSPGR sequence into the post-implant MR protocol to visualize the Sirius markers. Patients were scanned with different number-of-excitations (6, 8, 10), field-of-view (10cm, 14cm, 18cm), slice thickness (1mm, 0.8mm), flip angle (14 degrees, 20 degrees), bandwidth (122.070 Hz/pixel, 325.508 Hz/pixel, 390.625 Hz/pixel), phase encoding steps (160, 192, 224, 256), frequency-encoding direction (right/left, anterior/posterior), echo-time type (minimum-full, out-of-phase), field strength (1.5T, 3T), contrast (with, without), scanner vendor (Siemens, GE), coil (endorectal-coil only, endorectal-and-torso-coil, torsocoil only), endorectal-coil filling (30cc, 50cc) and endorectal-coil filling type (air, perfluorocarbon [PFC]). For post-implant dosimetric evaluation with greater anatomical detail, 3D-FSE images were fused with 3D-FSPGR images. For comparison with CT-based post-implant dosimetry, CT images were fused with 3D-FSPGR images. Results: The 3D-FSPGR sequence facilitated visualization of markers in patients. Marker visualization helped distinguish signal voids as seeds versus needle tracks for more definitive MR-based post-implant dosimetry. On the CT-MR fused images, the distance between the seed on CT to MR images was 3

  12. Automatic Brachytherapy Seed Placement Under MRI Guidance

    PubMed Central

    Patriciu, Alexandru; Petrisor, Doru; Muntener, Michael; Mazilu, Dumitru; Schär, Michael; Stoianovici, Dan

    2011-01-01

    The paper presents a robotic method of performing low dose rate prostate brachytherapy under magnetic resonance imaging (MRI) guidance. The design and operation of a fully automated MR compatible seed injector is presented. This is used with the MrBot robot for transperineal percutaneous prostate access. A new image-registration marker and algorithms are also presented. The system is integrated and tested with a 3T MRI scanner. Tests compare three different registration methods, assess the precision of performing automated seed deployment, and use the seeds to assess the accuracy of needle targeting under image guidance. Under the ideal conditions of the in vitro experiments, results show outstanding image-guided needle and seed placement accuracy. PMID:17694871

  13. [Brachytherapy in France: current situation and economic outlook due to the unavailability of iridium wires].

    PubMed

    Le Vu, B; Boucher, S

    2014-10-01

    In 2013, about 6000 patients were treated with brachytherapy, the number diminishing by 2.6% per year since 2008. Prostate, breast and gynecological cancers are the most common types of cancers. Since 2008, the number of brachytherapy facilities has decreased by 18%. In medicoeconomic terms, brachytherapy faces many problems: the coding system is outdated; brachytherapy treatments cost as much as internal radiation; fees do not cover costs; since iridium wire has disappeared from the market, the technique will be transferred to more expensive high-speed or pulse dose rates. The French financing grid based on the national study of costs lags behind changes in such treatments and in the best of cases, hospitals resorting to alternatives such as in-hospital brachytherapy are funded at 46% of their additional costs. Brachytherapy is a reference technique. With intense pressure on hospital pricing, financing brachytherapy facilities will become even more problematic as a consequence of the disappearance of iridium 192 wires. The case of brachytherapy illustrates the limits of the French financing system and raises serious doubts as to its responsiveness. PMID:25195115

  14. Remote interstitial afterloading in cancer of the prostate: preliminary experience with the MicroSelectron

    SciTech Connect

    Porter, A.T.; Scrimger, J.W.; Pocha, J.S.

    1988-03-01

    Brachytherapy in the treatment of prostate cancer is an accepted modality. A considerable experience has been accrued using Iridium interstitial therapy. The major problem associated with this choice is that of radioprotection. We describe the first clinical use of the MicroSelectron, a remote afterloading device, in prostate brachytherapy. Twenty-six patients have now been treated using this system. Approximately 55 treatment interruptions with an average 5 hr increase in overall treatment time occurs. The initial problems associated with instituting remote afterloading to prostate brachytherapy and their solutions are discussed.

  15. Plaque Brachytherapy for Uveal Melanoma: A Vision Prognostication Model

    SciTech Connect

    Khan, Niloufer; Khan, Mohammad K.; Bena, James; Macklis, Roger; Singh, Arun D.

    2012-11-01

    Purpose: To generate a vision prognostication model after plaque brachytherapy for uveal melanoma. Methods and Materials: All patients with primary single ciliary body or choroidal melanoma treated with iodine-125 or ruthenium-106 plaque brachytherapy between January 1, 2005, and June 30, 2010, were included. The primary endpoint was loss of visual acuity. Only patients with initial visual acuity better than or equal to 20/50 were used to evaluate visual acuity worse than 20/50 at the end of the study, and only patients with initial visual acuity better than or equal to 20/200 were used to evaluate visual acuity worse than 20/200 at the end of the study. Factors analyzed were sex, age, cataracts, diabetes, tumor size (basal dimension and apical height), tumor location, and radiation dose to the tumor apex, fovea, and optic disc. Univariate and multivariable Cox proportional hazards were used to determine the influence of baseline patient factors on vision loss. Kaplan-Meier curves (log rank analysis) were used to estimate freedom from vision loss. Results: Of 189 patients, 92% (174) were alive as of February 1, 2011. At presentation, visual acuity was better than or equal to 20/50 and better than or equal to 20/200 in 108 and 173 patients, respectively. Of these patients, 44.4% (48) had post-treatment visual acuity of worse than 20/50 and 25.4% (44) had post-treatment visual acuity worse than 20/200. By multivariable analysis, increased age (hazard ratio [HR] of 1.01 [1.00-1.03], P=.05), increase in tumor height (HR of 1.35 [1.22-1.48], P<.001), and a greater total dose to the fovea (HR of 1.01 [1.00-1.01], P<.001) were predictive of vision loss. This information was used to develop a nomogram predictive of vision loss. Conclusions: By providing a means to predict vision loss at 3 years after treatment, our vision prognostication model can be an important tool for patient selection and treatment counseling.

  16. Dosimetric audit in brachytherapy

    PubMed Central

    Bradley, D A; Nisbet, A

    2014-01-01

    Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace. PMID:24807068

  17. [Safety in brachytherapy].

    PubMed

    Marcié, S; Marinello, G; Peiffert, D; Lartigau, É

    2013-04-01

    No technique can now be used without previously considering the safety of patients, staff and public and risk management. This is the case for brachytherapy. The various aspects of brachytherapy are discussed for both the patient and the staff. For all, the risks must be minimized while achieving a treatment of quality. It is therefore necessary to establish a list as comprehensive as possible regardless of the type of brachytherapy (low, high, pulsed dose-rate). Then, their importance must be assessed with the help of their criticality. Radiation protection of personnel and public must take into account the many existing regulation texts. Four axes have been defined for the risk management for patients: organization, preparation, planning and implementation of treatment. For each axis, a review of risks is presented, as well as administrative, technical and medical dispositions for staff and the public. PMID:23465784

  18. Implicit active contours for automatic brachytherapy seed segmentation in fluoroscopy

    NASA Astrophysics Data System (ADS)

    Moult, Eric; Burdette, Clif; Song, Danny; Fichtinger, Gabor; Fallavollita, Pascal

    2012-02-01

    Motivation: In prostate brachytherapy, intra-operative dosimetry would be ideal to allow for rapid evaluation of the implant quality while the patient is still in the treatment position. Such a mechanism, however, requires 3-D visualization of the currently deposited seeds relative to the prostate. Thus, accurate, robust, and fully-automatic seed segmentation is of critical importance in achieving intra-operative dosimetry. Methodology: Implanted brachytherapy seeds are segmented by utilizing a region-based implicit active contour approach. Overlapping seed clusters are then resolved using a simple yet effective declustering technique. Results: Ground-truth seed coordinates were obtained via a published segmentation technique. A total of 248 clinical C-arm images from 16 patients were used to validate the proposed algorithm resulting in a 98.4% automatic detection rate with a corresponding 2.5% false-positive rate. The overall mean centroid error between the ground-truth and automatic segmentations was measured to be 0.42 pixels, while the mean centroid error for overlapping seed clusters alone was measured to be 0.67 pixels. Conclusion: Based on clinical data evaluation and validation, robust, accurate, and fully-automatic brachytherapy seed segmentation can be achieved through the implicit active contour framework and subsequent seed declustering method.

  19. Optimal drug release schedule for in-situ radiosensitization of image guided permanent prostate implants

    NASA Astrophysics Data System (ADS)

    Cormack, Robert A.; Nguyen, Paul L.; D'Amico, Anthony V.; Sridhar, Sri; Makrigiorgos, Mike

    2011-03-01

    Planned in-situ radiosensitization may improve the therapeutic ratio of image guided 125I prostate brachytherapy. Spacers used in permanent implants may be manufactured from a radiosensitizer-releasing polymer to deliver protracted localized sensitization of the prostate. Such devices will have a limited drug-loading capacity, and the drug release schedule that optimizes outcome, under such a constraint, is not known. This work determines the optimal elution schedules for 125I prostate brachytherapy. The interaction between brachytherapy dose distributions and drug distribution around drug eluting spacers is modeled using a linear-quadratic (LQ) model of cell kill. Clinical brachytherapy plans were used to calculate the biologic effective dose (BED) for planned radiation dose distributions while adding the spatial distributions of radiosensitizer while varying the temporal release schedule subject to a constraint on the drug capacity of the eluting spacers. Results: The greatest increase in BED is achieved by schedules with the greatest sensitization early in the implant. Making brachytherapy spacers from radiosensitizer eluting polymer transforms inert parts of the implant process into a means of enhancing the effect of the brachytherapy radiation. Such an approach may increase the therapeutic ratio of prostate brachytherapy or offer a means of locally boosting the radiation effect without increasing the radiation dose to surrounding tissues.

  20. [High dose rate brachytherapy].

    PubMed

    Aisen, S; Carvalho, H A; Chavantes, M C; Esteves, S C; Haddad, C M; Permonian, A C; Taier, M do C; Marinheiro, R C; Feriancic, C V

    1992-01-01

    The high dose rate brachytherapy uses a single source os 192Ir with 10Ci of nominal activity in a remote afterloading machine. This technique allows an outpatient treatment, without the inconveniences of the conventional low dose rate brachytherapy such as use of general anesthesia, rhachianesthesia, prolonged immobilization, and personal exposition to radiation. The radiotherapy department is now studying 5 basic treatment schemes concerning carcinomas of the uterine cervix, endometrium, lung, esophagus and central nervous system tumors. With the Micro Selectron HDR, 257 treatment sessions were done in 90 patients. Mostly were treated with weekly fractions, receiving a total of three to four treatments each. No complications were observed neither during nor after the procedure. Doses, fraction and ideal associations still have to be studied, so that a higher therapeutic ratio can be reached.

  1. Review of advanced catheter technologies in radiation oncology brachytherapy procedures

    PubMed Central

    Zhou, Jun; Zamdborg, Leonid; Sebastian, Evelyn

    2015-01-01

    The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented. PMID:26203277

  2. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications

    NASA Astrophysics Data System (ADS)

    Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

    2015-07-01

    In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled 125I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10-6 simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

  3. Prostate cancer radiotherapy 2002: the way forward.

    PubMed

    Lukka, Himu; Pickles, Tom; Morton, Gerard; Catton, Charles; Souhami, Luis; Warde, Padraig

    2005-02-01

    In November 2000, the GU Radiation Oncologists of Canada had their first meeting, "Controversies in prostate cancer radiotherapy: consensus development". The success of this meeting prompted a second meeting, held in December 2002 to discuss "The Way Forward" in prostate radiotherapy. Radiation oncologists from across Canada were brought together and integrated with key opinion leaders in prostate cancer treatment from throughout North America. The group debated current controversies including: intensity modulated radiotherapy (IMRT), external beam hypofractionation, high dose-rate brachytherapy, and hormone therapy in the management of prostate cancer. The meeting also sought to identify and prioritize clinical trial opportunities and to highlight steps required to achieve these research goals. In summary, advances involving IMRT have enabled the use of higher radiation doses without increasing morbidity. With renewed interest in hypofractionated radiation schedules, the value of hypofractionation using IMRT was discussed and initial results from ongoing clinical trials were presented. The emerging role for high dose-rate brachytherapy in higher risk patients was also discussed. Based on existing preliminary evidence the group expressed enthusiasm for further investigation of the role for brachytherapy in intermediate to high-risk patients. Despite significant advances in radiotherapy, hormone therapy continues to play an important role in prostate cancer treatment for patients with intermediate and high-risk disease. Although evidence supports the effectiveness of hormone therapy, the optimal timing, and duration of hormonal treatment are unclear. Results from ongoing clinical trials will provide insight into these questions and will assist in the design of future clinical trials.

  4. Magnetic resonance-guided prostate interventions.

    PubMed

    Haker, Steven J; Mulkern, Robert V; Roebuck, Joseph R; Barnes, Agnieska Szot; Dimaio, Simon; Hata, Nobuhiko; Tempany, Clare M C

    2005-10-01

    We review our experience using an open 0.5-T magnetic resonance (MR) interventional unit to guide procedures in the prostate. This system allows access to the patient and real-time MR imaging simultaneously and has made it possible to perform prostate biopsy and brachytherapy under MR guidance. We review MR imaging of the prostate and its use in targeted therapy, and describe our use of image processing methods such as image registration to further facilitate precise targeting. We describe current developments with a robot assist system being developed to aid radioactive seed placement. PMID:16924169

  5. Resolution and in vitro and initial in vivo evaluation of isomers of iodine-125-labeled 1-azabicyclo[2.2.2]oct-3-yl alpha-hydroxy-alpha-(1-iodo-1-propen-3-yl)-alpha-phenylacetate: a high-affinity ligand for the muscarinic receptor.

    PubMed

    McPherson, D W; Lambert, C R; Jahn, K; Sood, V; McRee, R C; Zeeberg, B; Reba, R C; Knapp, F F

    1995-09-29

    1-Azabicyclo[2.2.2]oct-3-yl alpha-hydroxy-alpha-(1-iodo-1-propen-3-yl)- alpha-phenylacetate (IQNP, 1), is a highly selective ligand for the muscarinic acetylcholinergic receptor (mAChR). There are eight stereoisomers in the racemic mixture. The optical isomers of alpha-hydroxy-alpha-phenyl-alpha-(1-propyn-3-yl)acetic acid were resolved as the alpha-methylbenzylamine salts, and the optical isomers of 3-quinuclidinol were resolved as the tartrate salts. The E and Z isomers were prepared by varying the reaction conditions for the stannylation of the triple bond followed by purification utilizing flash column chromatography. In vitro binding assay of the four stereoisomers containing the (R)-(-)-3-quinuclidinyl ester demonstrated that each isomer of 1 bound to mAChR with high affinity. In addition, (E)-(-)-(-)-IQNP demonstrated the highest receptor subtype specificity between the m1 molecular subtype (KD, nM, 0.383 +/- 0.102) and the m2 molecular subtype (29.6 +/- 9.70). In vivo biodistribution studies demonstrated that iodine-125-labeled (E)-(-)-(+)-1 cleared rapidly from the brain and heart. In contrast, iodine-125-labeled (E)-(-)-(-)-, (Z)-(-)-(-)-, and (Z)-(-)-(+)-1 have high uptake and retention in mAChR rich areas of the brain. It was also observed that (E)-(-)-(-)-IQNP demonstrated an apparent subtype selectivity in vivo with retention in M1 (m1, m4) mAChR areas of the rain. In addition, (Z)-(-)-(-)-IQNP also demonstrated significant uptake in tissues containing the M2 (m2) mAChR subtype. These results demonstrate that the iodine-123-labeled analogues of the (E)-(-)-(-)- and (Z)-(-)-(-)-IQNP isomers are attractive candidates for single-photon emission-computed tomographic imaging of cerebral and cardiac mAChR receptor densities.

  6. Dosimetric and technical aspects of intraoperative I-125 brachytherapy for stage I non-small cell lung cancer.

    PubMed

    Johnson, Mark; Colonias, Athanasios; Parda, David; Trombetta, Mark; Gayou, Olivier; Reitz, Bodo; Miften, Moyed

    2007-03-01

    Initial treatment outcome data from our institution for stage I non-small cell lung cancer (NSCLC) patients have shown that sublobar resection in combination with iodine-125 (I-125) brachytherapy is associated with recurrence rates of 2.0%, compared to 18.6% with sublobar resection alone. In this work, the technical and dosimetric aspects required to execute this procedure from the radiation oncology perspective as well as an analysis of the dose distributions of patients treated with this technique are presented. In this treatment technique, I-125 seeds in vicryl suture are embedded into vicryl mesh and surgically inserted providing a 2.0 cm margin on each side of the resection staple line. A nomogram is developed to determine the suture spacing in the vicryl mesh, as a function of seed activity in order to deliver 120 Gy at a distance of 0.5 cm above and below the seed array. Post-operative dosimetry consists of a CT-based planning and dose volume analysis. Dose distributions, dose volume histograms and mean dose data for lung are analysed in a group of patients. Dosimetric results show significant lung sparing with only a small volume of lung irradiated for all patients with mean lung dose values ranging from 1.5 Gy to 5.4 Gy. Lung brachytherapy with I-125 at the time of sublobar resection is a highly conformal option of dose delivery for stage I NSCLC patients with compromised physiologic reserve. Patient-related toxicity clinically measured by loss of pulmonary function and radiation-induced pneumonitis have not been linked to this procedure.

  7. Dosimetric and technical aspects of intraoperative I-125 brachytherapy for stage I non-small cell lung cancer

    NASA Astrophysics Data System (ADS)

    Johnson, Mark; Colonias, Athanasios; Parda, David; Trombetta, Mark; Gayou, Olivier; Reitz, Bodo; Miften, Moyed

    2007-03-01

    Initial treatment outcome data from our institution for stage I non-small cell lung cancer (NSCLC) patients have shown that sublobar resection in combination with iodine-125 (I-125) brachytherapy is associated with recurrence rates of 2.0%, compared to 18.6% with sublobar resection alone. In this work, the technical and dosimetric aspects required to execute this procedure from the radiation oncology perspective as well as an analysis of the dose distributions of patients treated with this technique are presented. In this treatment technique, I-125 seeds in vicryl suture are embedded into vicryl mesh and surgically inserted providing a 2.0 cm margin on each side of the resection staple line. A nomogram is developed to determine the suture spacing in the vicryl mesh, as a function of seed activity in order to deliver 120 Gy at a distance of 0.5 cm above and below the seed array. Post-operative dosimetry consists of a CT-based planning and dose volume analysis. Dose distributions, dose volume histograms and mean dose data for lung are analysed in a group of patients. Dosimetric results show significant lung sparing with only a small volume of lung irradiated for all patients with mean lung dose values ranging from 1.5 Gy to 5.4 Gy. Lung brachytherapy with I-125 at the time of sublobar resection is a highly conformal option of dose delivery for stage I NSCLC patients with compromised physiologic reserve. Patient-related toxicity clinically measured by loss of pulmonary function and radiation-induced pneumonitis have not been linked to this procedure.

  8. Prostate Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Prostate Cancer What is Prostate Cancer? How Tumors Form The body is made up ... the Escape (Esc) button on your keyboard.) How Prostate Cancer Occurs Prostate cancer occurs when a tumor forms ...

  9. A retrospective comparison of androgen deprivation (AD) vs. no AD among low-risk and intermediate-risk prostate cancer patients treated with brachytherapy, external beam radiotherapy, or radical prostatectomy

    SciTech Connect

    Ciezki, Jay P. . E-mail: ciezkij@ccf.org; Klein, Eric A.; Angermeier, Kenneth; Ulchaker, James; Chehade, Nabil; Altman, Andrew; Mahadevan, Arul; Reddy, Chandana A.

    2004-12-01

    Purpose: To examine the value of androgen deprivation (AD) in the curative treatment of low- and intermediate-risk prostate cancer treated with the three major modalities: radical retropubic prostatectomy (RRP), external beam radiotherapy (EBRT), and permanent prostate implantation (PI). Methods and materials: During 1996-2001, 1668 patients with low- and intermediate-risk prostate cancer were treated at The Cleveland Clinic Foundation. Only patients with a minimum of 2 years of prostate-specific antigen follow-up were included in the analysis, and biochemical relapse-free survival (bRFS) was used as the endpoint. Patients were grouped according to treatment modality and stratified according to the use of AD. Results: The overall 5-year bRFS rate was 87.8%. The 5-year bRFS rate for low-risk patients was 89% and for intermediate-risk patients was 79%. For low-risk patients, the 5-year bRFS rates by treatment modality (without AD vs. with AD, respectively) were PI: 90% vs. 93%; EBRT: 90% vs. 93%; and RRP: 89% vs. 84%. For intermediate-risk patients, the 5-year bRFS rates by treatment modality (without AD vs. with AD, respectively) were PI: 88% vs. 82%; EBRT: 81% vs. 84%; and RRP: 75% vs. 72%. None of the comparisons within risk groups or among modalities supports an increased efficacy with the use of AD. Conclusion: Five-year bRFS rates in low-risk and intermediate-risk patients are not improved by the use of AD.

  10. Incorporating seed orientation in brachytherapy implant reconstruction

    NASA Astrophysics Data System (ADS)

    Zhou, Yu; Jain, Ameet K.; Chirikjian, Gregory S.; Fichtinger, Gabor

    2006-03-01

    Intra-operative quality assurance and dosimetry optimization in prostate brachytherapy critically depends on the ability of discerning the locations of implanted seeds. Various methods exist for seed matching and reconstruction from multiple segmented C-arm images. Unfortunately, using three or more images makes the problem NP-hard, i.e. no polynomial-time algorithm can provably compute the complete matching. Typically, a statistical analysis of performance is considered sufficient. Hence it is of utmost importance to exploit all the available information in order to minimize the matching and reconstruction errors. Current algorithms use only the information about seed centers, disregarding the information about the orientations and length of seeds. While the latter has little dosimetric impact, it can positively contribute to improving seed matching rate and 3D implant reconstruction accuracy. It can also become critical information when hidden and spuriously segmented seeds need to be matched, where reliable and generic methods are not yet available. Expecting orientation information to be useful in reconstructing large and dense implants, we have developed a method which incorporates seed orientation information into our previously proposed reconstruction algorithm (MARSHAL). Simulation study shows that under normal segmentation errors, when considering seed orientations, implants of 80 to 140 seeds with the density of 2.0- 3.0 seeds/cc give an average matching rate >97% using three-image matching. It is higher than the matching rate of about 96% when considering only seed positions. This means that the information of seed orientations appears to be a valuable additive to fluoroscopy-based brachytherapy implant reconstruction.

  11. Observations on rotating needle insertions using a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, M. A.; Ferrier, N. J.; Thomadsen, B. R.

    2007-09-01

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  12. Recurrent abscess after MammoSite brachytherapy.

    PubMed

    Lopchinsky, Richard A; Giles, Kristina A

    2004-01-01

    Recently a new catheter was introduced to facilitate brachytherapy in a lumpectomy cavity. Data are limited on the side effects of high-dose brachytherapy to the lumpectomy cavity with the MammoSite catheter. We present a case of recurrent abscesses over a 7-month period in the lumpectomy cavity after MammoSite brachytherapy.

  13. Dosimetric equivalence of nonstandard HDR brachytherapy catheter patterns

    SciTech Connect

    Cunha, J. A. M.; Hsu, I-C.; Pouliot, J.

    2009-01-15

    Purpose: To determine whether alternative high dose rate prostate brachytherapy catheter patterns can result in similar or improved dose distributions while providing better access and reducing trauma. Materials and Methods: Standard prostate cancer high dose rate brachytherapy uses a regular grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. This study used CT datasets with 3 mm slice spacing from ten previously treated patients and digitized new catheters following three hypothetical catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a plan must fulfill the RTOG-0321 dose criteria for target dose coverage (V{sub 100}{sup Prostate}>90%) and organ-at-risk dose sparing (V{sub 75}{sup Bladder}<1 cc, V{sub 75}{sup Rectum}<1 cc, V{sub 125}{sup Urethra}<<1 cc). Results: The three nonstandard catheter patterns used 16 nonparallel, straight divergent catheters, with entry points in the perineum. Thirty plans from ten patients with prostate sizes ranging from 26 to 89 cc were optimized. All nonstandard patterns fulfilled the RTOG criteria when the clinical plan did. In some cases, the dose distribution was improved by better sparing the organs-at-risk. Conclusion: Alternative catheter patterns can provide the physician with additional ways to treat patients previously considered unsuited for brachytherapy treatment (pubic arch interference) and facilitate robotic guidance of

  14. Prostate elastography: preliminary in vivo results

    NASA Astrophysics Data System (ADS)

    Alam, S. K.; Feleppa, E. J.; Kalisz, A.; Ramchandran, S.; Ennis, R. D.; Lizzi, Frederick L.; Wuu, C.-S.; Ketterling, Jeffrey A.

    2005-04-01

    We report preliminary results from our investigation of in vivo prostate elastography. Fewer than 50% of all prostate cancers are typically visible in current clinical imaging modalities. Elastography displays a map of strain that results when tissue is externally compressed. Thus, elastography is ideal for imaging prostate cancers because they are generally stiffer than the surrounding tissue and stiffer regions usually exhibit lower strain in elastograms. In our study, digital radio-frequency (RF) ultrasound echo data were acquired from prostate-cancer patients undergoing brachytherapy. Seed placement is guided by a transrectal ultrasound (TRUS) probe, which is held in a mechanical fixture. The probe can be moved in XYZ directions and tilted. The probe face, in contact with the rectal wall, is used to apply a compression force to the immediately adjacent prostate. We also used a water-filled (acoustic) coupling balloon to compress the prostate by increasing the water volume inside the balloon. In each scan plane (transverse), we acquired RF data from successive scans at the scanner frame rate as the deformation force on the rectal wall was continuously increased. We computed strain using 1D RF cross-correlation analysis. The compression method based on fixture displacement produced low-noise elastograms that beautifully displayed the prostate architecture and emphasized stiff areas. Balloon-based compression also produced low-noise elastograms. Initial results demonstrate that elastography may be useful in the detection and evaluation of prostate cancers, occult in conventional imaging modalities.

  15. Brachytherapy in Gynecologic Cancers: Why Is It Underused?

    PubMed

    Han, Kathy; Viswanathan, Akila N

    2016-04-01

    Despite its established efficacy, brachytherapy is underused in the management of cervical and vaginal cancers in some parts of the world. Possible reasons for the underutilization of brachytherapy include the adoption of less invasive techniques, such as intensity-modulated radiotherapy; reimbursement policies favoring these techniques over brachytherapy; poor physician or patient access to brachytherapy; inadequate maintenance of brachytherapy skills among practicing radiation oncologists; transitioning to high-dose-rate (HDR) brachytherapy with increased time requirements; and insufficient training of radiation oncology residents.

  16. Synchronous prostate and rectal adenocarcinomas irradiation utilising volumetric modulated arc therapy.

    PubMed

    Ng, Sweet Ping; Tran, Thu; Moloney, Philip; Sale, Charlotte; Mathlum, Maitham; Ong, Grace; Lynch, Rod

    2015-12-01

    Cases of synchronous prostate and colorectal adenocarcinomas have been sporadically reported. There are case reports on patients with synchronous prostate and rectal cancers treated with external beam radiotherapy alone or combined with high-dose rate brachytherapy boost to the prostate. Here, we illustrate a patient with synchronous prostate and rectal cancers treated using the volumetric arc therapy (VMAT) technique. The patient was treated with radical radiotherapy to 50.4 Gy in 28 fractions to the pelvis, incorporating the involved internal iliac node and the prostate. A boost of 24 Gy in 12 fractions was delivered to the prostate only, using VMAT. Treatment-related toxicities and follow-up prostate-specific antigen and carcinoembryonic antigen were collected for data analysis. At 12 months, the patient achieved complete response for both rectal and prostate cancers without significant treatment-related toxicities. PMID:27512575

  17. Brachytherapy dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F. C.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2015-07-01

    In-vivo and in-situ measurement of the radiation dose administered during brachytherapy faces several technical challenges, requiring a very compact, tissue-equivalent, linear and highly sensitive dosimeter, particularly in low-dose rate brachytherapy procedures, which use radioactive seeds with low energy and low dose deposition rate. In this work we present a scintillating optical fiber dosimeter composed of a flexible sensitive probe and a dedicated electronic readout system based on silicon photomultiplier photodetection, capable of operating both in pulse and current modes. The performance of the scintillating fiber optic dosimeter was evaluated in low energy regimes, using an X-ray tube operating at voltages of 40-50 kV and currents below 1 mA, to assess minimum dose response of the scintillating fiber. The dosimeter shows a linear response with dose and is capable of detecting mGy dose variations like an ionization chamber. Besides fulfilling all the requirements for a dosimeter in brachytherapy, the high sensitivity of this device makes it a suitable candidate for application in low-dose rate brachytherapy. According to Peralta and Rego [1], the BCF-10 and BCF-60 scintillating optical fibers used in dosimetry exhibit high variations in their sensitivity for photon beams in the 25-100 kVp energy range. Energy linearity for energies below 50 keV needs to be further investigated, using monochromatic X-ray photons.

  18. Feasibility of functional imaging for brachytherapy

    PubMed Central

    2009-01-01

    This review summarizes the current understanding of the feasibility of functional imaging for brachytherapy. In following subsections the role of ultrasound, power doppler imaging, positron emission tomography, magnetic resonance imaging, dynamic dose calculation and targeted brachytherapy is analyzed. The combination of functional imaging with the new tools for intraoperative dose calculation and optimization opens new and exciting times in brachytherapy. New optimized protocols are needed and should be tested in controlled trials, to demonstrate an advantage of such a new paradigm.

  19. Image-based brachytherapy for cervical cancer.

    PubMed

    Vargo, John A; Beriwal, Sushil

    2014-12-10

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced cervical

  20. Transurethral light delivery for prostate photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Guo, Xiaoyu; Song, Danny Y.; Boctor, Emad M.

    2015-03-01

    Photoacoustic imaging has broad clinical potential to enhance prostate cancer detection and treatment, yet it is challenged by the lack of minimally invasive, deeply penetrating light delivery methods that provide sufficient visualization of targets (e.g., tumors, contrast agents, brachytherapy seeds). We constructed a side-firing fiber prototype for transurethral photoacoustic imaging of prostates with a dual-array (linear and curvilinear) transrectal ultrasound probe. A method to calculate the surface area and, thereby, estimate the laser fluence at this fiber tip was derived, validated, applied to various design parameters, and used as an input to three-dimensional Monte Carlo simulations. Brachytherapy seeds implanted in phantom, ex vivo, and in vivo canine prostates at radial distances of 5 to 30 mm from the urethra were imaged with the fiber prototype transmitting 1064 nm wavelength light with 2 to 8 mJ pulse energy. Prebeamformed images were displayed in real time at a rate of 3 to 5 frames per second to guide fiber placement and beamformed offline. A conventional delay-and-sum beamformer provided decreasing seed contrast (23 to 9 dB) with increasing urethra-to-target distance, while the short-lag spatial coherence beamformer provided improved and relatively constant seed contrast (28 to 32 dB) regardless of distance, thus improving multitarget visualization in single and combined curvilinear images acquired with the fiber rotating and the probe fixed. The proposed light delivery and beamforming methods promise to improve key prostate cancer detection and treatment strategies.

  1. Influence of trace elements in human tissue in low-energy photon brachytherapy dosimetry

    NASA Astrophysics Data System (ADS)

    White, Shane A.; Landry, Guillaume; van Gils, Francis; Verhaegen, Frank; Reniers, Brigitte

    2012-06-01

    The aim of this paper is to determine the dosimetric impact of trace elements in human tissues for low-energy photon sources used in brachytherapy. Monte Carlo dose calculations were used to investigate the dosimetric effect of trace elements present in normal or cancerous human tissues. The effect of individual traces (atomic number Z = 11-30) was studied in soft tissue irradiated by low-energy brachytherapy sources. Three other tissue types (prostate, adipose and mammary gland) were also simulated with varying trace concentrations to quantify the contribution of each trace to the dose distribution. The dose differences between cancerous and healthy prostate tissues were calculated in single- and multi-source geometries. The presence of traces in a tissue produces a difference in the dose distribution that is dependent on Z and the concentration of the trace. Low-Z traces (Na) have a negligible effect (<0.3%) in all tissues, while higher Z (K) had a larger effect (>3%). There is a potentially significant difference in the dose distribution between cancerous and healthy prostate tissues (4%) and even larger if compared to the trace-free composition (15%) in both single- and multi-sourced geometries. Trace elements have a non-negligible (up to 8% in prostate D90) effect on the dose in tissues irradiated with low-energy photon sources. This study underlines the need for further investigation into accurate determination of the trace composition of tissues associated with low-energy brachytherapy. Alternatively, trace elements could be incorporated as a source of uncertainty in dose calculations. This work was part of an invited presentation at the ‘International Workshop on Recent Advances in Monte Carlo Techniques for Radiation Therapy’, held in Montreal, June 8-10, 2011.

  2. Ultrasonic Detection and Imaging of Brachytherapy Seeds Based on Singular Spectrum Analysis

    NASA Astrophysics Data System (ADS)

    Mamou, J.; Feleppa, E. J.

    A commonly used, effective method of treating localized prostate cancer is implantation of small radioactive seeds. The standard imaging modality for treatment-planning dosimetry and for guiding and monitoring seed implantation is transrectal ultrasound (TRUS). However, movement of the prostate during seed insertion can cause seed misplacement, hemorrhage, and clutter from calcifications and other hyperechogenic scattering objects, and the specularity of seeds themselves make detecting seeds and verifying proper dosimetry difficult in an intraoperative time frame. Radiation oncologists would find a real-time imaging system that is capable of providing accurate, post-insertion, seed-location information to be very valuable because the information would enable timely feedback for intraoperatively correcting deficiencies in the radiation dose. Therefore, a remaining challenge for TRUS-guided brachytherapy of prostate cancer is accurate detection and localization of the seeds upon their insertion.

  3. Thermoluminescence dosimetry measurements of brachytherapy sources in liquid water

    SciTech Connect

    Tailor, Ramesh; Tolani, Naresh; Ibbott, Geoffrey S.

    2008-09-15

    Radiation therapy dose measurements are customarily performed in liquid water. The characterization of brachytherapy sources is, however, generally based on measurements made with thermoluminescence dosimeters (TLDs), for which contact with water may lead to erroneous readings. Consequently, most dosimetry parameters reported in the literature have been based on measurements in water-equivalent plastics, such as Solid Water. These previous reports employed a correction factor to transfer the dose measurements from a plastic phantom to liquid water. The correction factor most often was based on Monte Carlo calculations. The process of measuring in a water-equivalent plastic phantom whose exact composition may be different from published specifications, then correcting the results to a water medium leads to increased uncertainty in the results. A system has been designed to enable measurements with TLDs in liquid water. This system, which includes jigs to support water-tight capsules of lithium fluoride in configurations suitable for measuring several dosimetric parameters, was used to determine the correction factor from water-equivalent plastic to water. Measurements of several {sup 125}I and {sup 131}Cs prostate brachytherapy sources in liquid water and in a Solid Water phantom demonstrated a correction factor of 1.039{+-}0.005 at 1 cm distance. These measurements are in good agreement with a published value of this correction factor for an {sup 125}I source.

  4. Prostate motion during standard radiotherapy as assessed by fiducial markers.

    PubMed

    Crook, J M; Raymond, Y; Salhani, D; Yang, H; Esche, B

    1995-10-01

    From November 1993 to August 1994, 55 patients with localized prostate carcinoma had three gold seeds placed in the prostate under transrectal ultrasound guidance prior to the start of radiotherapy in order to track prostate motion. Patients had a planning CT scan before initial simulation and again at about 40 Gy, just prior to simulation of a field reduction. Seed position relative to fixed bony landmarks (pubic symphysis and both ischial tuberosities) was digitized from each pair of orthogonal films from the initial and boost simulation using the Nucletron brachytherapy planning system. Vector analysis was performed to rule out the possibility of independent seed migration within the prostate between the time of initial and boost simulation. Prostate motion was seen in the posterior (mean: 0.56 cm; SD: 0.41 cm) and inferior directions (mean: 0.59 cm; SD: 0.45 cm). The base of the prostate was displaced more than 1 cm posteriorly in 30% of patients and in 11% in the inferior direction. Prostate position is related to rectal and bladder filling. Distension of these organs displaces the prostate in an anterosuperior direction, with lesser degrees of filling allowing the prostate to move posteriorly and inferiorly. Conformal therapy planning must take this motion into consideration. Changes in prostate position of this magnitude preclude the use of standard margins. PMID:8539455

  5. High activity iodine 125 endocurietherapy for recurrent skull base tumors

    SciTech Connect

    Kumar, P.P.; Good, R.R.; Leibrock, L.G.; Mawk, J.R.; Yonkers, A.J.; Ogren, F.P.

    1988-04-15

    Experience with endocurietherapy of skull base tumors is reviewed. We present our cases of recurrent pituitary hemangiopericytoma, radiation-induced recurrent meningioma, recurrent clival chordoma, recurrent nasopharyngeal cancer involving the cavernous sinus, and recurrent parotid carcinoma of the skull base which were all successfully retreated with high-activity 125-iodine (I-125) permanent implantation.76 references.

  6. Iodine-125 metaraminol: A new platelet specific labeling agent

    SciTech Connect

    Ohmomo, Y.; Yokoyama, A.; Kawaii, K.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1984-01-01

    In the search for a platelet specific labeling agent, Metaraminol (MA), which is a sympatomimetic amine used for the treatment of hypotension, cardiogenic shock and well recognized as a drug actively incorporated and accumulated in platelet, attracted the authors' attention. Using the classical chloramine-T iodination method, a high labeling efficiency near 98%, reaching a specific activity up to about 1000 Ci/mmole was obtained. Upon the harvest of platelet, only as platelet rich plasma (PRP), the labeling with this radiopharmaceutical was easily performed by incubation at 37/sup 0/C for 10 min. Labeling efficiency as high as 63.0 +- 3.1% at 24 x 10/sup 8/ cells/ml was obtained. In in-vitro studies, the unaltered state of I-125 MA labeled platelet, with their cellular functions fully retained was demonstrated. Pharmacological study indicated a specific incorporation of I-125 MA by active transport system similar to that of 5-HT, along with passive diffusion. Then the in-vivo study carried out in rabbits with induced thrombi on the femoral artery, showed rather rapid disappearance of the I-125 MA labeled autologous platelet radioactivity, from circulating blood reaching as high thrombus-to-blood activity ratio as 19.8+-4.3 within 30 min post-administration. This new platelet labeling agent, I-125 MA, has many advantages over the use of IN-111 oxine and holds considerable promise for thrombus imaging with single photon emission CT upon the availability of I-123 MA.

  7. Organ distribution of Corynebacterium parvum labeled with iodine-125.

    PubMed

    Dimitrov, N V; Greenberg, C S; Denny, T

    1977-02-01

    Administration of iv, ip, single sc, multiple sc, and footpad injections of [125I]Corynebacterium parvum in mice revealed different patterns of radioactive vaccine distribution in various organs. High deposition and retention were found in the liver, spleen, and gastrointestinal tract and less in the lungs, kidneys, thymus, and bone marrow. Control animals given 125I showed very rapid clearance of the isotope and no retention in the organs. The pattern of distribution of [125I]C. parvum could be useful when protocols for clinical trials are designed.

  8. Afterloading: The Technique That Rescued Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2015-07-01

    Although brachytherapy had been established as a highly effective modality for the treatment of cancer, its application was threatened by mid-20th century due to appreciation of the radiation hazard to health care workers. This review examines how the introduction of afterloading eliminated exposure and ushered in a brachytherapy renaissance.

  9. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices

    SciTech Connect

    Siauw, Timmy; Cunha, Adam; Atamtuerk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2011-07-15

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. Methods: The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Results: Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core{sup TM}2 Duo CPU 1.67 GHz processor with 3 Gib RAM. Conclusions: IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.

  10. The Effects of Metallic Implants on Electroporation Therapies: Feasibility of Irreversible Electroporation for Brachytherapy Salvage

    SciTech Connect

    Neal, Robert E.; Smith, Ryan L.; Kavnoudias, Helen; Rosenfeldt, Franklin Ou, Ruchong; Mclean, Catriona A.; Davalos, Rafael V.; Thomson, Kenneth R.

    2013-12-15

    Purpose: Electroporation-based therapies deliver brief electric pulses into a targeted volume to destabilize cellular membranes. Nonthermal irreversible electroporation (IRE) provides focal ablation with effects dependent on the electric field distribution, which changes in heterogeneous environments. It should be determined if highly conductive metallic implants in targeted regions, such as radiotherapy brachytherapy seeds in prostate tissue, will alter treatment outcomes. Theoretical and experimental models determine the impact of prostate brachytherapy seeds on IRE treatments. Materials and Methods: This study delivered IRE pulses in nonanimal, as well as in ex vivo and in vivo tissue, with and in the absence of expired radiotherapy seeds. Electrical current was measured and lesion dimensions were examined macroscopically and with magnetic resonance imaging. Finite-element treatment simulations predicted the effects of brachytherapy seeds in the targeted region on electrical current, electric field, and temperature distributions. Results: There was no significant difference in electrical behavior in tissue containing a grid of expired radiotherapy seeds relative to those without seeds for nonanimal, ex vivo, and in vivo experiments (all p > 0.1). Numerical simulations predict no significant alteration of electric field or thermal effects (all p > 0.1). Histology showed cellular necrosis in the region near the electrodes and seeds within the ablation region; however, there were no seeds beyond the ablation margins. Conclusion: This study suggests that electroporation therapies can be implemented in regions containing small metallic implants without significant changes to electrical and thermal effects relative to use in tissue without the implants. This supports the ability to use IRE as a salvage therapy option for brachytherapy.

  11. EM-navigated catheter placement for gynecologic brachytherapy: an accuracy study

    NASA Astrophysics Data System (ADS)

    Mehrtash, Alireza; Damato, Antonio; Pernelle, Guillaume; Barber, Lauren; Farhat, Nabgha; Viswanathan, Akila; Cormack, Robert; Kapur, Tina

    2014-03-01

    Gynecologic malignancies, including cervical, endometrial, ovarian, vaginal and vulvar cancers, cause significant mortality in women worldwide. The standard care for many primary and recurrent gynecologic cancers consists of chemoradiation followed by brachytherapy. In high dose rate (HDR) brachytherapy, intracavitary applicators and /or interstitial needles are placed directly inside the cancerous tissue so as to provide catheters to deliver high doses of radiation. Although technology for the navigation of catheters and needles is well developed for procedures such as prostate biopsy, brain biopsy, and cardiac ablation, it is notably lacking for gynecologic HDR brachytherapy. Using a benchtop study that closely mimics the clinical interstitial gynecologic brachytherapy procedure, we developed a method for evaluating the accuracy of image-guided catheter placement. Future bedside translation of this technology offers the potential benefit of maximizing tumor coverage during catheter placement while avoiding damage to the adjacent organs, for example bladder, rectum and bowel. In the study, two independent experiments were performed on a phantom model to evaluate the targeting accuracy of an electromagnetic (EM) tracking system. The procedure was carried out using a laptop computer (2.1GHz Intel Core i7 computer, 8GB RAM, Windows 7 64-bit), an EM Aurora tracking system with a 1.3mm diameter 6 DOF sensor, and 6F (2 mm) brachytherapy catheters inserted through a Syed-Neblett applicator. The 3D Slicer and PLUS open source software were used to develop the system. The mean of the targeting error was less than 2.9mm, which is comparable to the targeting errors in commercial clinical navigation systems.

  12. EM-Navigated Catheter Placement for Gynecologic Brachytherapy: An Accuracy Study

    PubMed Central

    Mehrtash, Alireza; Damato, Antonio; Pernelle, Guillaume; Barber, Lauren; Farhat, Nabgha; Viswanathan, Akila; Cormack, Robert; Kapur, Tina

    2014-01-01

    Gynecologic malignancies, including cervical, endometrial, ovarian, vaginal and vulvar cancers, cause significant mortality in women worldwide. The standard care for many primary and recurrent gynecologic cancers consists of chemoradiation followed by brachytherapy. In high dose rate (HDR) brachytherapy, intracavitary applicators and/or interstitial needles are placed directly inside the cancerous tissue so as to provide catheters to deliver high doses of radiation. Although technology for the navigation of catheters and needles is well developed for procedures such as prostate biopsy, brain biopsy, and cardiac ablation, it is notably lacking for gynecologic HDR brachytherapy. Using a benchtop study that closely mimics the clinical interstitial gynecologic brachytherapy procedure, we developed a method for evaluating the accuracy of image-guided catheter placement. Future bedside translation of this technology offers the potential benefit of maximizing tumor coverage during catheter placement while avoiding damage to the adjacent organs, for example bladder, rectum and bowel. In the study, two independent experiments were performed on a phantom model to evaluate the targeting accuracy of an electromagnetic (EM) tracking system. The procedure was carried out using a laptop computer (2.1GHz Intel Core i7 computer, 8GB RAM, Windows 7 64-bit), an EM Aurora tracking system with a 1.3mm diameter 6 DOF sensor, and 6F (2 mm) brachytherapy catheters inserted through a Syed-Neblett applicator. The 3D Slicer and PLUS open source software were used to develop the system. The mean of the targeting error was less than 2.9mm, which is comparable to the targeting errors in commercial clinical navigation systems. PMID:25076828

  13. Testicular shielding in penile brachytherapy

    PubMed Central

    Bindal, Arpita; Tambe, Chandrashekhar M.; Ghadi, Yogesh; Murthy, Vedang; Shrivastava, Shyam Kishore

    2015-01-01

    Purpose Penile cancer, although rare, is one of the common genitourinary cancers in India affecting mostly aged uncircumcised males. For patients presenting with small superficial lesions < 3 cm restricted to glans, surgery, radical external radiation or brachytherapy may be offered, the latter being preferred as it allows organ and function preservation. In patients receiving brachytherapy, testicular morbidity is not commonly addressed. With an aim to minimize and document the doses to testis after adequate shielding during radical interstitial brachytherapy for penile cancers, we undertook this study in 2 patients undergoing brachytherapy and forms the basis of this report. Material and methods Two patients with early stage penile cancer limited to the glans were treated with radical high-dose-rate (HDR) brachytherapy using interstitial implant. A total of 7-8 tubes were implanted in two planes, parallel to the penile shaft. A total dose of 44-48 Gy (55-60 Gy EQD2 doses with α/β = 10) was delivered in 11-12 fractions of 4 Gy each delivered twice daily. Lead sheets adding to 11 mm (4-5 half value layer) were interposed between the penile shaft and scrotum. The testicular dose was measured using thermoluminescent dosimeters. For each patient, dosimetry was done for 3 fractions and mean calculated. Results The cumulative testicular dose to left and right testis was 31.68 cGy and 42.79 cGy for patient A, and 21.96 cGy and 23.28 cGy for patient B. For the same patients, the mean cumulative dose measured at the posterior aspect of penile shaft was 722.15 cGy and 807.72 cGy, amounting to 16.4% and 16.8% of the prescribed dose. Hence, the application of lead shield 11 mm thick reduced testicular dose from 722-808 cGy to 21.96-42.57 cGy, an “absolute reduction” of 95.99 ± 1.5%. Conclusions With the use of a simple lead shield as described, we were able to effectively reduce testicular dose from “spermicidal” range to “oligospermic” range with possible

  14. Dynamic rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-12-15

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process.Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D{sub 90} for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and {sup 192}Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D{sub 2cc} of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β= 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively.Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci{sup 192}Ir source, and the average HR-CTV D{sub 90} was 78.9 Gy. In order to match the HR-CTV D{sub 90} of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D{sub 90} above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively

  15. Prostate Cancer

    MedlinePlus

    ... man's bladder that produces fluid for semen. Prostate cancer is common among older men. It is rare ... younger than 40. Risk factors for developing prostate cancer include being over 65 years of age, family ...

  16. Prostate cancer.

    PubMed

    Castillejos-Molina, Ricardo Alonso; Gabilondo-Navarro, Fernando Bernardo

    2016-04-01

    Prostate cancer is the most frequent tumor found in men worldwide and in Mexico in particular. Age and family history are the main risk factors. The diagnosis is made by prostate biopsy in patients with abnormalities detected in their prostate-specific antigen (PSA) levels or digital rectal exam (DRE). This article reviews screening and diagnostic methods as well as treatment options for patients diagnosed with prostate cancer. PMID:27557386

  17. Prostate Diseases

    MedlinePlus

    The prostate is a gland in men. It helps make semen, the fluid that contains sperm. The prostate surrounds the tube that carries urine away from ... and out of the body. A young man's prostate is about the size of a walnut. It ...

  18. Novel tools for stepping source brachytherapy treatment planning: Enhanced geometrical optimization and interactive inverse planning

    SciTech Connect

    Dinkla, Anna M. Laarse, Rob van der; Koedooder, Kees; Petra Kok, H.; Wieringen, Niek van; Pieters, Bradley R.; Bel, Arjan

    2015-01-15

    Purpose: Dose optimization for stepping source brachytherapy can nowadays be performed using automated inverse algorithms. Although much quicker than graphical optimization, an experienced treatment planner is required for both methods. With automated inverse algorithms, the procedure to achieve the desired dose distribution is often based on trial-and-error. Methods: A new approach for stepping source prostate brachytherapy treatment planning was developed as a quick and user-friendly alternative. This approach consists of the combined use of two novel tools: Enhanced geometrical optimization (EGO) and interactive inverse planning (IIP). EGO is an extended version of the common geometrical optimization method and is applied to create a dose distribution as homogeneous as possible. With the second tool, IIP, this dose distribution is tailored to a specific patient anatomy by interactively changing the highest and lowest dose on the contours. Results: The combined use of EGO–IIP was evaluated on 24 prostate cancer patients, by having an inexperienced user create treatment plans, compliant to clinical dose objectives. This user was able to create dose plans of 24 patients in an average time of 4.4 min/patient. An experienced treatment planner without extensive training in EGO–IIP also created 24 plans. The resulting dose-volume histogram parameters were comparable to the clinical plans and showed high conformance to clinical standards. Conclusions: Even for an inexperienced user, treatment planning with EGO–IIP for stepping source prostate brachytherapy is feasible as an alternative to current optimization algorithms, offering speed, simplicity for the user, and local control of the dose levels.

  19. What is Prostate Cancer?

    MedlinePlus

    ... Topic Key statistics for prostate cancer What is prostate cancer? Cancer starts when cells in the body begin ... through the center of the prostate. Types of prostate cancer Almost all prostate cancers are adenocarcinomas . These cancers ...