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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 after iodine-125 prostate brachytherapy. Prostate volume and International Prostate Symptom Score were the most important predictors 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. Magnetic Resonance Imaging-Defined Treatment Margins in Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita; Patil, Nikhilesh; Ma, Clement; McLean, Michael; Borg, Jette

    2010-07-15

    Purpose: Low-dose-rate prostate brachytherapy achieves a very high and effective intraprostatic dose. Implant quality parameters concentrate on the dose received by the prostate (D90, V100) but not that received by the periprostatic tissue. We calculated implant quality parameters, D90 and V100, for the magnetic resonance imaging (MRI)-defined prostate plus 2, 3, and 5 mm. Methods and Materials: A total of 131 men with early-stage prostate cancer treated with iodine-125 brachytherapy represent all those treated with brachytherapy monotherapy in our institution in 2005. Postplan assessment was performed at 1 month using magnetic resonance (MR)-computed tomography (CT) fusion. The prostate V100 and D90 were calculated with 2-, 3-, and 5-mm margins. Results were compared with those in 8 patients with biopsy-proven local failure occurring in an experience of more than 1,100 implants. Results: Mean prostate V100 (SD) and D90 (SD) were 95.6% (4.1) and 117.2% (12.7). For prostate plus a 2-mm margin the D90 was 107.9% (14.3) and for a 3-mm margin 96.0 % (14.0). For prostate plus a 5-mm margin, the D90 was only 78.4% (11.0). The 8 patients experiencing local failure, despite adequate implants, had a lower mean V100 of 91.2% (SD, 2.8; p = 0.0008) and D90 of 103.7% (SD, 8.3; p = 0.002) and significantly inferior margin coverage. Conclusions: Satisfactory coverage of a 2-mm and 3-mm periprostatic margin is obtained with the described planning approach. Coverage falls off significantly by 5 mm. The 8 patients who experienced local failure had significantly lower doses than the margin cohort. Although the V100 and D90 would be considered acceptable, the fall-off in margin coverage was observed by 3 mm.

  4. 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.

  5. Predicting the severity of acute urinary toxicity after brachytherapy with iodine-125 for localized prostate cancer.

    PubMed

    Takeda, Ken; Jingu, Keichi; Koto, Masashi; Fujimoto, Keisuke; Narazaki, Kakutaro; Kubozono, Masaki; Saito, Hideo; Yamada, Shigeyuki; Mitsuduka, Kohji; Ishidoya, Shigeto; Ariga, Hisanori; Arai, Yoichi; Yamada, Shogo

    2011-01-01

    Prostate cancer is one of the common cancers in the world. In Japan, prostate brachytherapy (PB) with iodine-125 has become a treatment option for localized prostate cancer since 2003. Nevertheless, severe acute urinary toxicity (AUT) remains as one of the intractable side effects. We assessed AUT and the changes in international prostate symptom score (IPSS) before and after PB for localized prostate cancer. IPSS is a questionnaire tool for tracking the subjective urinary symptoms. Between 2006 and 2009, 104 eligible patients underwent PB with iodine-125 were analyzed. AUT was graded with the radiation therapy oncology group (RTOG) scale. Eligible patients filled out IPSS questionnaires before and after PB. Clinical and treatment-related factors were examined for correlation with the severity of AUT and the interval to IPSS resolution. AUT of RTOG Grade 0 (no changes) and Grade 2 was detected in one and 96 patients, respectively, whereas seven patients (6.7%) experienced AUT of Grade 3. Thus, the incidence of severe AUT (Grade 3) after PB was low. A greater number of needles (p = 0.012) were associated with AUT of RTOG Grade 3 on the univariate analysis. The median interval to IPSS resolution was 6 months (7 ± 6 months). Greater post-implant maximal IPSS (p < 0.001) was associated with slower IPSS resolution, whereas higher pre-implant IPSS (p < 0.001) was associated with faster IPSS resolution on the multivariate analysis. In conclusion, reducing the number of needles in PB may be helpful for decreasing the rate of severe AUT. PMID:21212603

  6. 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.

  7. Biochemical Disease-Free Rate and Toxicity for Men Treated With Iodine-125 Prostate Brachytherapy With D{sub 90} {>=}180 Gy

    SciTech Connect

    Gomez-Iturriaga Pina, Alfonso; Crook, Juanita; Borg, Jette; Ma, Clement

    2010-10-01

    Purpose: Iodine-125 ({sup 125}I) prostate brachytherapy is planned with a prescribed dose of 145 Gy and minimal dose received by 90% of the prostate (D{sub 90}) of 120-125% (174-181 Gy). We examined the clinical outcomes and toxicity profile of men receiving a D{sub 90} (isodose enclosing 90% of the prostate) of {>=}180 Gy. Methods and Materials: Between March 1999 and May 2006, 129 men (17% of our total brachytherapy population) treated with {sup 125}I monotherapy for Stage T1-T2 prostate cancer received a D{sub 90} {>=}180 Gy. Implants were performed using transrectal ultrasonography and fluoroscopic guidance. The 1-month postplan dosimetry used magnetic resonance imaging-computed tomography fusion. The minimal follow-up was 2 years. Toxicity was scored according to the National Cancer Institute Common Terminology Criteria for Adverse Events toxicity scale, version 3. Results: The median patient age was 63 years (range, 50-76), and the pretreatment prostate-specific antigen level was 5.5 ng/mL (range, 0.6-13.5). The Gleason score was {<=}6 in 125 patients and was 7 in 4 patients. The median follow-up period was 40 months (range, 24-111), and the median D{sub 90} was 186 Gy. The median minimal dose received by 30% of the urethra was 203 Gy, and the median rectal volume receiving a minimum of 100% of the prescribed dose was 0.81 cm{sup 3}. Acute Grade 2 genitourinary toxicity was seen in 5.4% and late Grade 2 in 7%. Late urinary retention (Grade 3) was seen in 2 patients (1.5%). Grade 1 rectal bleeding occurred in 9.3% and Grade 2 in 2.3%. On univariate logistic regression analysis, none of the clinical and dosimetric parameters predicted for rectal bleeding. Of 110 men who were potent before treatment, 81% remained potent 5 years after treatment. Three biochemical failures and only one local failure developed. The 5-year biochemical no evidence of disease rate using the 'nadir plus 2' definition was 96.8%. Conclusion: A D{sub 90} of {>=}180 Gy is associated with excellent biochemical disease-free survival and acceptable toxicity.

  8. Correlation Between Pre- and Postimplant Dosimetry for Iodine-125 Seed Implants for Localized Prostate Cancer

    SciTech Connect

    Al-Qaisieh, Bashar; Witteveen, Thelma Carey, Brendan; Henry, Ann; Bottomley, David; Smith, Jonathan; Franks, Kevin; Bownes, Peter

    2009-10-01

    Purpose: In order to evaluate implant quality for permanent prostate brachytherapy in patients with localized prostate cancer, American Brachytherapy Society and ESTRO guidelines recommend that postimplant dosimetry should be performed. To understand more about the relationship between pre- and postimplant dosimetry, a comparison was made of patients who received iodine-125 ({sup 125}I) brachytherapy between March 1995 and the end of 2004, using a preplan technique. Methods and Materials: CT postimplant dosimetry was available for 707 patients. Detailed dose volume analysis was performed using both preimplant ultrasound and postimplant CT data sets for a subgroup of 445 patients. The following parameters were compared: prostate volume covered by 100% of the prescription dose (Vp100), Vp150, and Vp200 and dose to 90% (D90) of the prostate. In addition, volume implanted (Vi) parameters were used to compare pre- and postimplant dosimetry. Vi parameters describe dose levels inside the patient, based on number of seeds, seed activity, and their spatial distribution relative to each other, without reference to the actual prostate volume or position. Results: The mean {+-} standard deviation values of preimplant (34.7 {+-} 8.9 cm{sup 3}) and postimplant (36.7 {+-} 9.4 cm{sup 3}) prostate volumes were similar. The mean ({+-}standard deviation) planned D90 was 183.4 ({+-}12.1) Gy while the D90 that was achieved was 145.5 ({+-}20.4) Gy. Over the study period, there was a steady increase of the average D90. Postimplant CT D90 and Vp100 values correlated significantly (R = 0.84; p < 0.001). The Vi and Vp parameters all showed a strong correlation. Conclusions: In this study, we showed that there is a strong correlation between transrectal ultrasound-based preimplant and CT-based postimplant dosimetry. The excellent correlation between prostate D90 and V100 values demonstrates they are both equally valid quality indices. Vi parameters are an additional measure that can be used to assess the quality of the implant.

  9. Permanent Iodine-125 Interstitial Planar Seed Brachytherapy for Close or Positive Margins for Thoracic Malignancies

    SciTech Connect

    Mutyala, Subhakar; Stewart, Alexandra; Khan, Atif J.; Cormack, Robert A.; O'Farrell, Desmond; Sugarbaker, David; Devlin, Phillip M.

    2010-03-15

    Purpose: To assess toxicity and outcome following permanent iodine-125 seed implant as an adjunct to surgical resection in cases of advanced thoracic malignancy. Methods and Materials: An institutional review board-approved retrospective review was performed. Fifty-nine patients were identified as having undergone thoracic brachytherapy seed implantation between September 1999 and December 2006. Data for patient demographics, tumor details, and morbidity and mortality were recorded. Results: Fifty-nine patients received 64 implants. At a median follow-up of 17 months, 1-year and 2-year Kaplan-Meier rates of estimated overall survival were 94.1% and 82.0%, respectively. The 1-year and 2-year local control rates were 80.1% and 67.4%, respectively. The median time to develop local recurrence was 11 months. Grades 3 and 4 toxicity rates were 12% at 1 year. Conclusions: This review shows relatively low toxicity for interstitial planar seed implantation after thoracic surgical resection. The high local control results suggest that an incomplete oncologic surgery plus a brachytherapy implant for treating advanced thoracic malignancy merit further investigation.

  10. Visual Acuity, Contrast Sensitivity and Color Vision Three Years After Iodine-125 Brachytherapy for Choroidal and Ciliary Body Melanoma

    PubMed Central

    Tsui, Irena; Beardsley, Robert M; McCannel, Tara A; Oliver, Scott C; Chun, Melissa W; Lee, Steve P; Chow, Phillip E; Agazaryan, Nzhde; Yu, Fei; Straatsma, Bradley R

    2015-01-01

    Purpose : To report visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after iodine-125 brachytherapy for choroidal and ciliary body melanoma (CCM). Design : Prospective interventional case series. Participants : Thirty-seven patients (37 eyes) with CCM. Methods : Patients had best-corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, Pelli-Robson contrast sensitivity and Hardy-Rand-Rittler color vision measurement; comprehensive ophthalmology examination; optical coherence tomography; and ultrasonography at baseline prior to, 1 year after, 2 years after and 3 years after I-125 brachytherapy. Main Outcome Measures : Visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after brachytherapy. Results : Nineteen (19) men and 18 women with mean age of 58 years (SD 13, range 30-78) prior to, 1 year after, 2 years after and 3 years after brachytherapy had mean best-corrected visual acuity of 77 letters (20/32), 65 letters (20/50), 56 letters (20/80) and 47 letters (20/125); contrast sensitivity of 30, 26, 22 and 19 letters; color vision of 26, 20, 17 and 14 test figures, respectively. Decrease in visual acuity, contrast sensitivity and color vision was statistically significant from baseline at 1 year, 2 years, and 3 years after brachytherapy. Decreased acuity at 3 years was associated with mid-choroid and macula melanoma location, ? 4.1 mm melanoma height, radiation maculopathy and radiation optic neuropathy. Conclusion : 1, 2 and 3 years after brachytherapy, eyes with CCM had significantly decreased visual acuity, contrast sensitivity and color vision. PMID:26312123

  11. 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.

  12. 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.

  13. 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 ...

  14. Patterns of recurrence of malignant astrocytoma following stereotactic interstitial brachytherapy with iodine-125 implants.

    PubMed

    Agbi, C B; Bernstein, M; Laperriere, N; Leung, P; Lumley, M

    1992-01-01

    The pattern of tumor recurrence was studied in a series of 68 patients who were treated with interstitial brachytherapy for malignant astrocytoma. Thirty-six patients had newly diagnosed tumors and were treated following surgery and external beam therapy, while 32 were treated for recurrent tumors. Recurrence pattern was determined using computed tomography at the time of clinical deterioration. Thirty-eight percent of tumor recurrence occurred within the original tumor margin and 50% occurred at the original site but extended beyond the initial margin. In all, 88.0% recurred at the initial tumor site, 71.4% being confined to within 2 cm of the pretreatment tumor borders while 6.0% recurred intracranially outside of the initial tumor margin. One patient recurred with spinal metastasis while two patients developed systemic metastases. The significance of these findings is discussed. PMID:1587753

  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 ?m in case patients and 408.5 ?m 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 for the treatment of uveal melanoma resulted in fewer abnormal maculas, lower central macular thickness on OCT, and a trend toward better final visual acuity in comparison with matched control patients who underwent brachytherapy alone.

  16. In Vivo Dosimetry With a Linear MOSFET Array to Evaluate the Urethra Dose During Permanent Implant Brachytherapy Using Iodine-125

    SciTech Connect

    Bloemen-van Gurp, Esther J.; Haanstra, Bjoerk K.C.; Murrer, Lars H.P.; Gils, Francis C.J.M. van; Dekker, Andre L.A.J.; Mijnheer, Ben J.; Lambin, Philippe

    2009-11-15

    Purpose: To develop a technique to monitor the dose rate in the urethra during permanent implant brachytherapy using a linear MOSFET array, with sufficient accuracy and without significantly extending the implantation time. Methods and Materials: Phantom measurements were performed to determine the optimal conditions for clinical measurements. In vivo measurements were performed in 5 patients during the {sup 125}I brachytherapy implant procedure. To evaluate if the urethra dose obtained in the operating room with the ultrasound transducer in the rectum and the patient in treatment position is a reference for the total accumulated dose; additional measurements were performed after the implantation procedure, in the recovery room. Results: In vivo measurements during and after the implantation procedure agree very well, illustrating that the ultrasound transducer in the rectum and patient positioning do not influence the measured dose in the urethra. In vivo dose values obtained during the implantation are therefore representative for the total accumulated dose in the urethra. In 5 patients, the dose rates during and after the implantation were below the maximum dose rate of the urethra, using the planned seed distribution. Conclusion: In vivo dosimetry during the implantation, using a MOSFET array, is a feasible technique to evaluate the dose in the urethra during the implantation of {sup 125}I seeds for prostate brachytherapy.

  17. 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.

  18. An analysis of brachytherapy with computed tomography-guided permanent implantation of Iodine-125 seeds for recurrent nonkeratin nasopharyngeal carcinoma

    PubMed Central

    Shen, Xinying; Li, Yong; Zhang, Yanfang; Kong, Jian; Li, Yanhao

    2015-01-01

    Background 125I seed implantation is a new method in treatment of nasopharyngeal carcinoma (NPC), and it is worthwhile to evaluate its feasibility. In this study, we performed brachytherapy with computed tomography (CT)-guided permanent implantation of 125I seeds in the treatment of patients with the recurrence of NPC. Methods A total 30 patients (20 male and ten female) at the median age of 55 (range 25–80) years were diagnosed with recurrent nonkeratin NPC, with a total 38 lesions and a short disease-free interval (mediañ11 months) after primary radiotherapy alone or combined with chemotherapy. Patients received CT scan, starting from 2 months after the treatment. Follow-up was conducted for ~2–38 months to observe the local control rate and overall survival rate. We also analyzed the possible correlation between survival periods and the status of recurrent tumors. Results The local control rates at 6, 12, 24, 30, and 36 months after the procedure of 125I seed implantation were 86.8%, 73.7%, 26.3%, 15.8%, and 5.3%, respectively. The overall 1-, 2-, and 3-year survival rates were 80.0% (24/30), 30.0% (9/30), and 6.7% (2/30), respectively, with a median survival period of 18 months (17.6±8.6 months). Interestingly, the survival periods of the patients who had primary radiotherapy with or without chemotherapy were 15.8±7.9 and 24.3±7.9 months, respectively. Kaplan–Meier survival analysis demonstrated that ?2 (log rank) was 7.555, with very significant difference (P<0.01). The survival periods of patients in tumor stages I, II, III, and IV were 25.4±8.7, 19.8±9.4, 16.1±4.5, and 12.8±7.8 months, respectively, with significant differences (P<0.05). Conclusion Our data suggest that the survival period of recurrent NPC patients after 125I seed implantation is inversely related to the tumor stages of the recurrence but not to chemotherapy after the primary radiotherapy. Therefore, CT-guided 125I seed implantation can be set for treatment of recurrent NPC, for better survival rate with minimal damage. PMID:25999732

  19. Bioassay for iodine-125

    SciTech Connect

    Chen, C.Y.; Chu, R.Y.L. Veterans Affairs Medical Center, Oklahoma City, OK )

    1990-06-01

    The use of the volatile form of iodine-125 ({sup 125}I) in clinics and laboratories often imposes the responsibility of bioassay on nuclear medicine personnel. The authors reviewed several methods with respect to regulations and guidelines. Urinalysis is sufficiently sensitive when performed within two days of accidental ingestion; however, an action level cannot be set unambiguously. In vivo measurement is preferred. Discussion of this method was illustrated by the calibration of their detector system.

  20. Exposure of Treating Physician to Radiation during Pro-state Brachytherapy using Iodine-125 Seeds

    E-print Network

    Krusche, Bernd

    Seeds Dose measurements on both hands with thermoluminescence dosimeters Hans Schiefer1 , Friedrich von-Peter Schmid2 , Thomas Leippold2 , Ladislav Prikler3 , Bernd Krusche4 , Jakob Roth5 , Daniel Engeler2 1 Klinik

  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. 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 leakage rates were observed. Considering the body fluid is more complex than saline, the in vivo leakage half-life, in case a source leak is encountered, may vary significantly from what is presented in this paper due to chemical reactions. In vivo measurements thus may produce a more accurate estimation of leakage half-life and thyroid uptake dose.

  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. Preoperative treatment planning with intraoperative optimization can achieve consistent high-quality implants in prostate brachytherapy

    SciTech Connect

    Kudchadker, Rajat J.; Pugh, Thomas J.; Swanson, David A.; Bruno, Teresa L.; Bolukbasi, Yasemin; Frank, Steven J.

    2012-01-01

    Advances in brachytherapy treatment planning systems have allowed the opportunity for brachytherapy to be planned intraoperatively as well as preoperatively. The relative advantages and disadvantages of each approach have been the subject of extensive debate, and some contend that the intraoperative approach is vital to the delivery of optimal therapy. The purpose of this study was to determine whether high-quality permanent prostate implants can be achieved consistently using a preoperative planning approach that allows for, but does not necessitate, intraoperative optimization. To achieve this purpose, we reviewed the records of 100 men with intermediate-risk prostate cancer who had been prospectively treated with brachytherapy monotherapy between 2006 and 2009 at our institution. All patients were treated with iodine-125 stranded seeds; the planned target dose was 145 Gy. Only 8 patients required adjustments to the plan on the basis of intraoperative findings. Consistency and quality were assessed by calculating the correlation coefficient between the planned and implanted amounts of radioactivity and by examining the mean values of the dosimetric parameters obtained on preoperative and 30 days postoperative treatment planning. The amount of radioactivity implanted was essentially identical to that planned (mean planned radioactivity, 41.27 U vs. mean delivered radioactivity, 41.36 U; R{sup 2} = 0.99). The mean planned and day 30 prostate V100 values were 99.9% and 98.6%, respectively. The mean planned and day 30 prostate D90 values were 186.3 and 185.1 Gy, respectively. Consistent, high-quality prostate brachytherapy treatment plans can be achieved using a preoperative planning approach, mostly without the need for intraoperative optimization. Good quality assurance measures during simulation, treatment planning, implantation, and postimplant evaluation are paramount for achieving a high level of quality and consistency.

  6. Examination of dosimetry accuracy as a function of seed detection rate in permanent prostate brachytherapy

    SciTech Connect

    Su Yi; Davis, Brian J.; Herman, Michael G.; Manduca, Armando; Robb, Richard A.

    2005-09-15

    The variation of permanent prostate brachytherapy dosimetry as a function of seed detection rates was investigated for I125 implants with seed activities commonly employed in contemporary practice. Post-implant imaging and radiation dosimetry data from nine patients who underwent PPB served as the basis of this simulation study. One-thousand random configurations of detected seeds were generated for each patient dataset using various seed detection levels from 30% to 99%. Dose parameters, including D90, were computed for each configuration and compared with the actual dosimetry data. A total of 108 000 complete sets of post-PPB dose volume statistics were computed. The results demonstrated that although the average D90 differed from the true value by less than 5% when 70% or more seeds were identified, the D90 of an individual case could deviate up to 13%. The 95% confidence interval (CI) of estimated D90 values differ by less than 5% from the actual value when 95% or more seeds are detected, or approximately a 7 Gy difference in the D90 value for a prescription dose of 144 Gy. Estimated target volume dose parameters tended to decrease with reduced seed detection rates. The most variable dose parameter was the prostate V100 in absolute scale while the urethral V100 was most variable in a relative sense. Based on this comprehensive simulation study, it is suggested that 95% or more seeds need to be localized in order to provide an accurate estimation of dose parameters for contemporary iodine 125 permanent prostate brachytherapy.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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 disease. Patients with a high GS and/or short PSA-DT have a higher likelihood of developing metastatic disease and should be considered for systemic therapy.

  12. MCNP modeling of prostate brachytherapy and organ dosimetry 

    E-print Network

    Usgaonker, Susrut Rajanikant

    2004-09-30

    Using the computer code Monte Carlo N-Particle (MCNP), doses were calculated for organs of interest such as the large intestine, urinary bladder, testes, and kidneys while patients were undergoing prostate brachytherapy. This research is important...

  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. Methods for prostate stabilization during transperineal LDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Podder, Tarun; Sherman, Jason; Rubens, Deborah; Messing, Edward; Strang, John; Ng, Wan-Sing; Yu, Yan

    2008-03-01

    In traditional prostate brachytherapy procedures for a low-dose-rate (LDR) radiation seed implant, stabilizing needles are first inserted to provide some rigidity and support to the prostate. Ideally this will provide better seed placement and an overall improved treatment. However, there is much speculation regarding the effectiveness of using regular brachytherapy needles as stabilizers. In this study, we explored the efficacy of two types of needle geometries (regular brachytherapy needle and hooked needle) and several clinically feasible configurations of the stabilization needles. To understand and assess the prostate movement during seed implantation, we collected in vivo data from patients during actual brachytherapy procedures. In vitro experimentation with tissue-equivalent phantoms allowed us to further understand the mechanics behind prostate stabilization. We observed superior stabilization with the hooked needles compared to the regular brachytherapy needles (more than 40% in bilateral parallel needle configuration). Prostate movement was also reduced significantly when regular brachytherapy needles were in an angulated configuration as compared to the parallel configuration (more than 60%). When the hooked needles were angulated for stabilization, further reduction in prostate displacement was observed. In general, for convenience of dosimetric planning and to avoid needle collision, all needles are desired to be in a parallel configuration. In this configuration, hooked needles provide improved stabilization of the prostate. On the other hand, both regular and hooked needles appear to be equally effective in reducing prostate movement when they are in angulated configurations, which will be useful in seed implantation using a robotic system. We have developed nonlinear spring-damper model for the prostate movement which can be used for adapting dosimetric planning during brachytherapy as well as for developing more realistic haptic devices and training simulators.

  15. 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.

  16. 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 ?m thick nickel-titanium alloy (nitinol) tubes. The needle is 16-gauge (1.651 mm) in outer diameter and the catheter contains a 535 ?m 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%–44% if the clinician allows a urethral dose gradient volume of 0–5 mm around the urethra to receive a dose below the prescription. A multisource approach is necessary in order to deliver the proposed {sup 153}Gd-based I-RSBT technique in reasonable treatment times.

  17. 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.

  18. 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.

  19. 142pr glass seeds for the brachytherapy of prostate cancer 

    E-print Network

    Jung, Jae Won

    2007-09-17

    A beta-emitting glass seed was proposed for the brachytherapy treatment of prostate cancer. Criteria for seed design were derived and several beta-emitting nuclides were examined for suitability. 142Pr was selected as the isotope of choice. Seeds 0...

  20. 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.

  1. 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.

  2. 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 does not seem related to temporal testosterone changes.

  3. PSA Kinetics and PSA Bounce Following Permanent Seed Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita Gillan, Caitlin B.Sc.; Yeung, Ivan Ph.D.; Austen, Lynette; McLean, Michael; Lockwood, Gina M.Math.

    2007-10-01

    Purpose: To report the incidence, timing, and magnitude of the benign prostate-specific antigen (PSA) bounce after {sup 125}I prostate brachytherapy and correlate the bounce with clinical and/or dosimetric factors. Methods and Materials: From March 1999 to August 2003, a total of 292 men received {sup 125}I prostate brachytherapy without androgen deprivation or supplemental beam radiotherapy and have PSA follow-up >30 months. Implants were preplanned using transrectal ultrasound (TRUS) and performed under transrectal ultrasound/fluoroscopy guidance using preloaded needles. A PSA bounce is defined as an increase {>=}0.2 ng/ml with spontaneous return to prebounce level or lower. Results: Resolved PSA bounces were seen in 40% of men with follow-up >30 months. Median onset was 15 months, and median magnitude was 0.76 ng/ml. Magnitude >2 ng/ml was seen in 15%. The only clinical or dosimetric factor predictive of bounce in multivariate analysis was younger age. Median time to increasing PSA level indicative of failure was 30 months. Conclusions: Benign PSA bounces are common after {sup 125}I prostate brachytherapy, especially in younger men. An increase >2 ng/ml above the nadir was seen in 15%. Magnitude of increase does not distinguish bounce from failure. Time to the start of the PSA increase can be helpful, but is not absolute. The PSA bounce does not predict subsequent failure. Caution is advised in interpreting an early increasing PSA level in the first 30 months after {sup 125}I brachytherapy in favorable-risk patients.

  4. 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.

  5. 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.

  6. 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.

  7. Salvage brachytherapy for locally recurrent prostate cancer after external beam radiotherapy.

    PubMed

    Yamada, Yasuhiro; Okihara, Koji; Iwata, Tsuyoshi; Masui, Koji; Kamoi, Kazumi; Yamada, Kei; Miki, Tsuneharu

    2015-01-01

    External beam radiotherapy (EBRT) is a standard treatment for prostate cancer. Despite the development of novel radiotherapy techniques such as intensity-modulated conformal radiotherapy, the risk of local recurrence after EBRT has not been obviated. Various local treatment options (including salvage prostatectomy, brachytherapy, cryotherapy, and high-intensity focused ultrasound [HIFU]) have been employed in cases of local recurrence after primary EBRT. Brachytherapy is the first-line treatment for low-risk and selected intermediate-risk prostate tumors. However, few studies have examined the use of brachytherapy to treat post-EBRT recurrent prostate cancer. The purpose of this paper is to analyze the current state of our knowledge about the effects of salvage brachytherapy in patients who develop locally recurrent prostate cancer after primary EBRT. This article also introduces our novel permanent brachytherapy salvage method. PMID:26112477

  8. 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.

  9. 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 resulted from an excess of cardiovascular deaths. Changes in lifestyle to improve cardiovascular health may improve overall survival in patients with clinically localized prostate cancer.

  10. 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 1-30. Our data indicate that postimplant dosimetry on the day of implant is sufficient for patients with good dose coverage (Day 1 V{sub 100} >93%)

  11. In vivo photoacoustic imaging of prostate brachytherapy seeds

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    We conducted an approved canine study to investigate the in vivo feasibility of photoacoustic imaging for intraoperative updates to brachytherapy treatment plans. Brachytherapy seeds coated with black ink were inserted into the canine prostate using methods similar to a human procedure. A transperineal, interstitial, fiber optic light delivery method, coupled to a 1064 nm laser, was utilized to irradiate the prostate and the resulting acoustic waves were detected with a transrectal ultrasound probe. The fiber was inserted into a high dose rate (HDR) brachytherapy needle that acted as a light-diffusing sheath, enabling radial light delivery from the tip of the fiber inside the sheath. The axis of the fiber was located at a distance of 4-9 mm from the long axis of the cylindrical seeds. Ultrasound images acquired with the transrectal probe and post-operative CT images of the implanted seeds were analyzed to confirm seed locations. In vivo limitations with insufficient light delivery within the ANSI laser safety limit (100 mJ/cm2) were overcome by utilizing a short-lag spatial coherence (SLSC) beamformer, which provided average seed contrasts of 20-30 dB for energy densities ranging 8-84 mJ/cm2. The average contrast was improved by up to 20 dB with SLSC beamforming compared to conventional delay-and-sum beamforming. There was excellent agreement between photoacoustic, ultrasound, and CT images. Challenges included visualization of photoacoustic artifacts that corresponded with locations of the optical fiber and hyperechoic tissue structures.

  12. 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 malignancy risk compared with RP patients. Further follow-up of this cohort is needed given the potential latency of radiation-induced malignancies.

  13. 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.

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

    PubMed

    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. PMID:25531797

  15. 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 strategy in obese patients.

  16. 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.

  17. Difference in the rate of rectal complications following prostate brachytherapy based on the prostate-rectum distance and the prostate longitudinal length among early prostate cancer patients

    PubMed Central

    Kang, Moon Hyung; Yu, Young Dong; Shin, Hyun Soo; Oh, Jong Jin

    2015-01-01

    Purpose To investigate the difference in rectal complications rate following prostate low dose rate (LDR) brachytherapy based on prostate-rectum distance and prostate longitudinal length among early prostate cancer patients. Materials and Methods From March 2008 to February 2013, 245 prostate cancer patients with a Gleason score ?7 were treated with 125-I LDR brachytherapy. Among them, 178 patients with prostate volume 20-35 mL and a follow-up period ?6 months were evaluated for radiation proctitis. Magnetic resonance imaging (MRI) was performed for a prebrachytherapy evaluation, and prostate-rectum distance and prostate longitudinal length were measured. The radiation proctitis was confirmed and graded via colonoscopy based on the radiation therapy oncology group (RTOG) toxicity criteria. Results Twenty-three patients received a colonoscopy for proctitis evaluation, and 12 were identified as grade 1 on the RTOG scale. Nine patients were diagnosed as grade 2 and 2 patients were grade 3. No patient developed grade 4 proctitis. The rectal-complication group had a mean prostate-rectum distance of 2.51±0.16 mm, while non-rectal-complication control group had 3.32±0.31 mm. The grade 1 proctitis patients had a mean prostate-rectum distance of 2.80±0.15 mm, which was significantly longer than 2.12±0.31 mm of grades 2 and 3 patient groups (p=0.045). All 11 patients of grades 2 and 3 had a prostate longitudinal length of 35.22±2.50 mm, which was longer than group 1, but the difference was not statistically significant (p=0.214). Conclusions As the prostate-rectum distance increased, fewer postimplantation rectal symptoms were observed. Patients with a shorter prostate-rectum distance in MRI should receive modified implantation techniques or radical prostatectomy. PMID:26366276

  18. 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% ± 0.86%, and the prostate volume Dice overlap coefficient was 91.89% ± 1.19%. Conclusions: The authors have developed a novel approach to improve prostate contour utilizing intraoperative TRUS-based prostate volume in the CT-based prostate HDR treatment planning, demonstrated its clinical feasibility, and validated its accuracy with MRIs. The proposed segmentation method would improve prostate delineations, enable accurate dose planning and treatment delivery, and potentially enhance the treatment outcome of prostate HDR brachytherapy.

  19. 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.

  20. 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 rectum.

  1. Iodine-125 induces apoptosis via regulating p53, microvessel density, and vascular endothelial growth factor in colorectal cancer

    PubMed Central

    2014-01-01

    Background Iodine interstitial brachytherapy has been widely reported for treating colorectal cancer (CRC). However, the inhibitory molecular mechanism of iodine-125 (I-125) on CRC has not been reported. Methods To illustrate the inhibitory mechanism of iodine-125 (I-125) on CRC, we established the animal models of CRC via the injection of HCT-8 cells into nude mice. Subsequently, the I-125 granules were implanted into the tumor of the animal model at different dosages. Proliferating cell nuclear antigen and terminal transferase dUTP nick end labeling were used to detect the apoptosis of the tumor cells. Immunohistochemistry SP staining was used to measure the expression of p53 protein. The protein levels were examined with western blot and ELISA. Meanwhile, microvessel density (MVD) was counted by endothelial cells immunostained by anti-CD34 antibody. Results The results showed that I-125 protests against CRC via increasing the protein level of p53 and decreasing the level of vascular endothelial growth factor (VEGF), leading to the decrease of MVD in CRC (P <0.0001). An effective inhibition dosage of I-125 ranged from 0.4 to 0.8 mCi. Conclusions The inhibitory mechanisms of iodine on CRC acted through an increase in the level of p53 and a decrease in the level of VEGF, resulting in a decrease of MVD. PMID:25033896

  2. Predictors of Urinary Morbidity in Cs-131 Prostate Brachytherapy Implants

    SciTech Connect

    Smith, Ryan P.; Jones, Heather A.; Beriwal, Sushil; Gokhale, Abhay; Benoit, Ronald

    2011-11-01

    Purpose: Cesium-131 is a newer radioisotope being used in prostate brachytherapy (PB). This study was conducted to determine the predictors of urinary morbidity with Cs-131 PB. Methods and Materials: A cohort of 159 patients underwent PB with Cs-131 at our institution and were followed by using Expanded Prostate Cancer Index Composite (EPIC) surveys to determine urinary morbidity over time. EPIC scores were obtained preoperatively and postoperatively at 2 and 4 weeks, and 3 and 6 months. Different factors were evaluated to determine their individual effect on urinary morbidity, including patient characteristics, disease characteristics, treatment, and dosimetry. Multivariate analysis of covariance was carried out to identify baseline determinants affecting urinary morbidity. Factors contributing to the need for postoperative catheterization were also studied and reported. Results: At 2 weeks, patient age, dose to 90% of the organ (D90), bladder neck maximum dose (D{sub max}), and external beam radiation therapy (EBRT) predicted for worse function. At 4 weeks, age and EBRT continued to predict for worse function. At the 3-month mark, better preoperative urinary function, preoperative alpha blockers, bladder neck D{sub max}, and EBRT predicted for worse urinary morbidity. At 6 months, better preoperative urinary function, preoperative alpha blockers, bladder neck D{sub max}, and EBRT were predictive of increased urinary problems. High bladder neck D{sub max} and poor preoperative urinary function predicted for the need for catheterization. Conclusions: The use of EBRT plus Cs-131 PB predicts for worse urinary toxicity at all time points studied. Patients should be cautioned about this. Age was a consistent predictor of worsened morbidity immediately following Cs-131 PB, while bladder D{sub max} was the only consistent dosimetric predictor. Paradoxically, patients with better preoperative urinary function had worse urinary morbidity at 3 and 6 months, consistent with recently published literature.

  3. 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 normal structures or to unimodal radiotherapy techniques.

  4. Prostate brachytherapy seed reconstruction using an adaptive grouping technique

    SciTech Connect

    Su Yi; Davis, Brian J.; Furutani, Keith M.; Herman, Michael G.; Robb, Richard A.

    2007-07-15

    Fluoroscopy-based three-dimensional seed localization as a component of intraoperative dosimetry for prostate brachytherapy is an active area of research. A novel adaptive-grouping-based reconstruction approach is developed. This approach can recover overlapped seeds that are not detected from the fluoroscopic images. Two versions of the adaptive-grouping-based reconstruction approach are implemented and compared to an epipolar geometry-based seed reconstruction technique. Simulations based on nine patient datasets are used to validate the algorithms. A total of 2259 reconstructions is performed in which different types of error such as random noise in seed image locations and ambiguities in projection geometry are incorporated. Among those reconstructions, nine of the cases with overlapping seeds and the different types of error are performed. It is demonstrated that the adaptive-grouping-based reconstruction method is more accurate than the epipolar geometry method and allows faster reconstruction. At a random noise level of 0.6 mm, the mean distance error in reconstructed seed locations is approximately 1.0 mm for one of the relevant cases examined in detail. The best adaptive-grouping-based approach successfully recovered overlapped seeds in the majority of simulated cases (89%), with the remainder of cases generating one false positive seed. Phantom validation is also performed, and overlapped seeds are successfully recovered with all 92 seeds correctly localized and reconstructed. The mean distance error between segmented seed images and projected seeds is 0.5 mm in the phantom study.

  5. 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 dosimetry calculation in the non-deformed prostate – which may be used to more accurately reflect “true” dosimetry during planning.

  6. 76 FR 11526 - In the Matter of Dr. Gary Kao; Order Prohibiting Involvement In NRC-Licensed Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ...therapeutic purposes. The therapeutic treatments include brachytherapy iodine-125 used for permanent prostate implants. Dr. Kao was an approved authorized user for brachytherapy iodine-125 used for permanent prostate implants under the permit....

  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. 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.

  9. 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 in rabbit model.

  10. A gEUD-based inverse planning technique for HDR prostate brachytherapy: Feasibility study

    SciTech Connect

    Giantsoudi, D.; Baltas, D.; Karabis, A.; Mavroidis, P.; Zamboglou, N.; Tselis, N.; Shi, C.; Papanikolaou, N.

    2013-04-15

    Purpose: The purpose of this work was to study the feasibility of a new inverse planning technique based on the generalized equivalent uniform dose for image-guided high dose rate (HDR) prostate cancer brachytherapy in comparison to conventional dose-volume based optimization. Methods: The quality of 12 clinical HDR brachytherapy implants for prostate utilizing HIPO (Hybrid Inverse Planning Optimization) is compared with alternative plans, which were produced through inverse planning using the generalized equivalent uniform dose (gEUD). All the common dose-volume indices for the prostate and the organs at risk were considered together with radiobiological measures. The clinical effectiveness of the different dose distributions was investigated by comparing dose volume histogram and gEUD evaluators. Results: Our results demonstrate the feasibility of gEUD-based inverse planning in HDR brachytherapy implants for prostate. A statistically significant decrease in D{sub 10} or/and final gEUD values for the organs at risk (urethra, bladder, and rectum) was found while improving dose homogeneity or dose conformity of the target volume. Conclusions: Following the promising results of gEUD-based optimization in intensity modulated radiation therapy treatment optimization, as reported in the literature, the implementation of a similar model in HDR brachytherapy treatment plan optimization is suggested by this study. The potential of improved sparing of organs at risk was shown for various gEUD-based optimization parameter protocols, which indicates the ability of this method to adapt to the user's preferences.

  11. 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 dependent and can be obtained only after the treatment, an unpredictable error is unavoidable.

  12. Praseodymium-142 glass seeds for the brachytherapy of prostate cancer

    NASA Astrophysics Data System (ADS)

    Jung, Jae Won

    A beta-emitting glass seed was proposed for the brachytherapy treatment of prostate cancer. Criteria for seed design were derived and several beta-emitting nuclides were examined for suitability. 142Pr was selected as the isotope of choice. Seeds 0.08 cm in diameter and 0.9 cm long were manufactured for testing. The seeds were activated in the Texas A&M University research reactor. The activity produced was as expected when considering the meta-stable state and epi-thermal neutron flux. The MCNP5 Monte Carlo code was used to calculate the quantitative dosimetric parameters suggested in the American Association of Physicists in Medicine (AAPM) TG-43/60. The Monte Carlo calculation results were compared with those from a dose point kernel code. The dose profiles agree well with each other. The gamma dose of 142Pr was evaluated. The gamma dose is 0.3 Gy at 1.0 cm with initial activity of 5.95 mCi and is insignificant to other organs. Measurements were performed to assess the 2-dimensional axial dose distributions using Gafchromic radiochromic film. The radiochromic film was calibrated using an X-ray machine calibrated against a National Institute of Standards and Technology (NIST) traceable ion chamber. A calibration curve was derived using a least squares fit of a second order polynomial. The measured dose distribution agrees well with results from the Monte Carlo simulation. The dose was 130.8 Gy at 6 mm from the seed center with initial activity of 5.95 mCi. AAPM TG-43/60 parameters were determined. The reference dose rate for 2 mm and 6 mm were 0.67 and 0.02 cGy/s/mCi, respectively. The geometry function, radial dose function and anisotropy function were generated.

  13. Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate brachytherapy of the prostate cancer

    E-print Network

    Pouliot, Jean

    brachytherapy of the prostate cancer Yongbok Kim,a) I-Chow Joe Hsu, Etienne Lessard, and Jean Pouliot Department uncertainty. Catheter coordinates were extracted from five patients treated for prostate cancer, and three brachytherapy for prostate cancer has significantly improved the ability to define the targets and organs

  14. 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 multi-institutional setting.

  15. 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

  16. 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.

  17. Comparison of 3 different postimplant dosimetry methods following permanent {sup 125}I prostate seed brachytherapy

    SciTech Connect

    Marcu, Loredana G.; Gowda, Raghu

    2013-10-01

    Postimplant dosimetry (PID) after Iodine-125 ({sup 125}I) implant of the prostate should offer a reliable qualitative assessment. So far, there is no consensus regarding the optimum PID method, though the latest literature is in favor of magnetic resonance imaging (MRI). This study aims to simultaneously compare 3 PID techniques: (1) MRI-computed tomography (CT) fusion; (2) ultrasound (US)-CT fusion; and (3) manual target delineation on CT. The study comprised 10 patients with prostate cancer. CT/MR scans with urinary catheters in place for PID were done either on day 0 or day 1 postimplantation. The main parameter evaluated and compared among methods was target D90. The results show that CT-based D90s are lower than US-CT D90s (median difference,?6.85%), whereas MR-CT PID gives higher D90 than US-CT PID (median difference, 4.25%). Manual contouring on CT images tends to overestimate the prostate volume compared with transrectal ultrasound (TRUS) (median difference, 23.33%), whereas on US images the target is overestimated compared with MR-based contouring (median difference, 13.25%). Although there are certain differences among the results given by various PID techniques, the differences are statistically insignificant for this small group of patients. Any dosimetric comparison between 2 PID techniques should also account for the limitations of each technique, to allow for an accurate quantification of data. Given that PID after permanent radioactive seed implant is mandatory for quality assurance, any imaging method–based PID (MR-CT, US-CT, and CT) available in a radiotherapy department can be indicative of the quality of the procedure.

  18. The emerging role of high-dose-rate (HDR) brachytherapy as monotherapy for prostate cancer.

    PubMed

    Yoshioka, Yasuo; Yoshida, Ken; Yamazaki, Hideya; Nonomura, Norio; Ogawa, Kazuhiko

    2013-09-01

    High-dose-rate (HDR) brachytherapy as monotherapy is a comparatively new brachytherapy procedure for prostate cancer. In addition to the intrinsic advantages of brachytherapy, including radiation dose concentration to the tumor and rapid dose fall-off at the surrounding normal tissue, HDR brachytherapy can yield a more homogeneous and conformal dose distribution through image-based decisions for source dwell positions and by optimization of individual source dwell times. Indication can be extended even to T3a/b or a part of T4 tumors because the applicators can be positioned at the extracapsular lesion, into the seminal vesicles, and/or into the bladder, without any risk of source migration or dropping out. Unlike external beam radiotherapy, with HDR brachytherapy inter-/intra-fraction organ motion is not problematic. However, HDR monotherapy requires patients to stay in bed for 1-4 days during hospitalization, even though the actual overall treatment time is short. Recent findings that the ?/? value for prostate cancer is less than that for the surrounding late-responding normal tissue has made hypofractionation attractive, and HDR monotherapy can maximize this advantage of hypofractionation. Research on HDR monotherapy is accelerating, with a growing number of publications reporting excellent preliminary clinical results due to the high 'biologically effective dose (BED)' of >200 Gy. Moreover, the findings obtained for HDR monotherapy as an early model of extreme hypofractionation tend to be applied to other radiotherapy techniques such as stereotactic radiotherapy. All these developments point to the emerging role of HDR brachytherapy as monotherapy for prostate cancer. PMID:23543798

  19. 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.

  20. A new CT prostate segmentation for CT-based HDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Yang, Xiaofeng; Rossi, Peter; Ogunleye, Tomi; Jani, Ashesh B.; Curran, Walter J.; Liu, Tian

    2014-03-01

    High-dose-rate (HDR) brachytherapy has become a popular treatment modality for localized prostate cancer. Prostate HDR treatment involves placing 10 to 20 catheters (needles) into the prostate gland, and then delivering radiation dose to the cancerous regions through these catheters. These catheters are often inserted with transrectal ultrasound (TRUS) guidance and the HDR treatment plan is based on the CT images. The main challenge for CT-based HDR planning is to accurately segment prostate volume in CT images due to the poor soft tissue contrast and additional artifacts introduced by the catheters. To overcome these limitations, we propose a novel approach to segment the prostate in CT images through TRUS-CT deformable registration based on the catheter locations. In this approach, the HDR catheters are reconstructed from the intra-operative TRUS and planning CT images, and then used as landmarks for the TRUS-CT image registration. The prostate contour generated from the TRUS images captured during the ultrasound-guided HDR procedure was used to segment the prostate on the CT images through deformable registration. We conducted two studies. A prostate-phantom study demonstrated a submillimeter accuracy of our method. A pilot study of 5 prostate-cancer patients was conducted to further test its clinical feasibility. All patients had 3 gold markers implanted in the prostate that were used to evaluate the registration accuracy, as well as previous diagnostic MR images that were used as the gold standard to assess the prostate segmentation. For the 5 patients, the mean gold-marker displacement was 1.2 mm; the prostate volume difference between our approach and the MRI was 7.2%, and the Dice volume overlap was over 91%. Our proposed method could improve prostate delineation, enable accurate dose planning and delivery, and potentially enhance prostate HDR treatment outcome.

  1. 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.

  2. 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 literature. These results may explain why in earlier modeling studies, when the effects of edema, dose heterogeneity, and RBE were all ignored simultaneously, prostate LDR brachytherapy was reported to show an overall similar dose effect as EBRT and HDR brachytherapy, which are independent of edema and RBE effects and have a better dose coverage.

  3. 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.

  4. Development of a Pneumatic Robot for MRI-guided Transperineal Prostate Biopsy and Brachytherapy: New Approaches

    PubMed Central

    Song, Sang-Eun; Cho, Nathan B.; Fischer, Gregory; Hata, Nobuhito; Tempany, Clare; Fichtinger, Gabor; Iordachita, Iulian

    2011-01-01

    Magnetic Resonance Imaging (MRI) guided prostate biopsy and brachytherapy has been introduced in order to enhance the cancer detection and treatment. For the accurate needle positioning, a number of robotic assistants have been developed. However, problems exist due to the strong magnetic field and limited workspace. Pneumatically actuated robots have shown the minimum distraction in the environment but the confined workspace limits optimal robot design and thus controllability is often poor. To overcome the problem, a simple external damping mechanism using timing belts was sought and a 1-DOF mechanism test result indicated sufficient positioning accuracy. Based on the damping mechanism and modular system design approach, a new workspace-optimized 4-DOF parallel robot was developed for the MRI-guided prostate biopsy and brachytherapy. A preliminary evaluation of the robot was conducted using previously developed pneumatic controller and satisfying results were obtained. PMID:21399734

  5. On the Sensitivity of ?/? 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, ?/?, 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 ?/? 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 ?/? 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.

  6. Prostate-specific antigen bounce predicts for a favorable prognosis following brachytherapy: a meta-analysis

    PubMed Central

    Bernstein, Michael B.; Ohri, Nitin; Hodge, James W.; Garg, Madhur; Bodner, William; Kalnicki, Shalom; Dicker, Adam P.

    2013-01-01

    Purpose Controversy exists whether the prostate-specific antigen (PSA) bounce phenomenon following definitive radiation for prostate cancer has prognostic significance. Here, we perform a meta-analysis to determine the association between PSA bounce and biochemical control after brachytherapy alone. Material and methods We reviewed Medline, EMBASE, and CENTRAL citations through February 2012. Studies that recorded biochemical failure rates in bouncers and non-bouncers were included. Hazard ratios describing the impact of bounce on biochemical failure were extracted directly from the studies or calculated from survival curves. Pooled estimates were obtained using the inverse variance method. A random effects model was used in cases of significant effect heterogeneity (p < 0.10 using Q test). Results The final analysis included 3011 patients over 6 studies treated with brachytherapy. Meta-analysis revealed that patients experiencing PSA bounce after brachytherapy, conferred a decreased risk of biochemical failure (random effects model HR = 0.42, 95% CI: 0.30-0.59; p < 0.001). Conclusions Our meta-analysis determined that PSA bounce predicts for improved biochemical control following brachytherapy. To our knowledge, this is the first study describing this effect. PMID:24474969

  7. Acute Urinary Retention After I-125 Prostate Brachytherapy in Relation to Dose in Different Regions of the Prostate

    SciTech Connect

    Roeloffzen, Ellen M.A.; Monninkhof, Evelyn M.; Battermann, Jan J.; Roermund, Joep G.H. van; Moerland, Marinus A.; Vulpen, Marco van

    2011-05-01

    Purpose: To assess the influence of dose in different prostate regions, and the influence of anatomic variation on the risk of acute urinary retention (AUR) after I-125 prostate brachytherapy. Methods and Materials: In this case-control study, dosimetry and anatomy were compared between 50 patients with AUR (cases) and 50 patients without AUR (controls). Cases and controls were randomly selected from our database. The following structures were delineated on magnetic resonance imaging: prostate, urethra, peripheral zone, transitional zone, apex, base, midprostate, lower sphincter, and bladder neck. The dosimetric parameters analyzed were D{sub 10}, D{sub 50}, D{sub 90}, V{sub 100}, V{sub 150}, and V{sub 200}. The anatomic parameters analyzed were prostate protrusion into the bladder, bladder overlap, urethra angle, and urethra-bladder angle. The delineator was blinded to the patient's AUR status. Logistic regression analysis was used to investigate the association of these factors with AUR. Results: The dose delivered to different regions of the prostate was not significantly associated with the risk of AUR. Only dose to the bladder neck was significantly associated with AUR (odds ratio 1.13 per 10 Gy; 95% CI 1.02;1.26; p = 0.023). Mean bladder neck D{sub 90} was 65 Gy in AUR cases vs. 56 Gy in controls (p = 0.016), and mean bladder neck D{sub 10} was 128 Gy vs. 107 Gy, respectively (p = 0.018). Furthermore, on univariate analysis, a larger extent of both bladder overlap and of prostate protrusion were associated with a higher risk of AUR (odds ratio 1.16; 95% CI 1.04-1.28; p = 0.005, and odds ratio 1.83; 95% CI 1.37-2.45; p < 0.001, respectively). The mean extent of prostate protrusion was 3.5 mm in AUR cases vs. 1.0 mm in controls (p < 0.001). Odds ratios did not change substantially after adjustment for potential confounders. On multivariate analysis, the extent of prostate protrusion seemed to be a stronger risk factor for AUR than bladder overlap. Conclusion: The risk of AUR is not associated with dose delivered to different regions of the prostate. However, a higher dose to the bladder neck and a larger extent of prostate protrusion into the bladder are risk factors for the development of AUR after I-125 prostate brachytherapy.

  8. 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 implant (learning curve). Over the course of the program, we have deliberately reduced the number of needles and OR time per patient, which have potentially minimized intraoperative trauma and may have contributed to less toxicity. A learning curve in prostate brachytherapy programs affect not only the outcome but also the toxicity from the treatment.

  9. 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.

  10. Sexual function after permanent 125I-brachytherapy for prostate cancer.

    PubMed

    Mabjeesh, N; Chen, J; Beri, A; Stenger, A; Matzkin, H

    2005-01-01

    We prospectively assessed patients' erectile function (EF) using the International Index of Erectile Function (IIEF) and a global assessment questionnaire (GAQ) following permanent 125I-brachytherapy for localized prostate cancer. Of 378 treated patients, 220 had a minimal 2-y follow-up and 131/220 were sexually active prior to brachytherapy, with an EF domain score of > or = 11 (study group). Patients were allowed sildenafil at any time of the study. The patients' mean EF score, without excluding patients who used sildenafil, dropped within 3 months after brachytherapy, recovered at the end of the first year and remained unchanged for at least up to 2 y after treatment regardless of the addition of neoadjuvant hormone therapy to 125I-brachytherapy. Analysis of the GAQ revealed that 80% of the patients were satisfied with their sexual function up to 3 y after treatment. Any detrimental effect of permanent brachytherapy with or without the addition of hormone therapy on EF is reversible, and recovery is expected at 1 y after treatment in most patients. PMID:15510186

  11. Low-dose-rate or high-dose-rate brachytherapy in treatment of prostate cancer – between options

    PubMed Central

    2013-01-01

    Purpose Permanent low-dose-rate (LDR-BT) and temporary high-dose-rate (HDR-BT) brachytherapy are competitive techniques for clinically localized prostate radiotherapy. Although a randomized trial will likely never to be conducted comparing these two forms of brachytherapy, a comparative analysis proves useful in understanding some of their intrinsic differences, several of which could be exploited to improve outcomes. The aim of this paper is to look for possible similarities and differences between both brachytherapy modalities. Indications and contraindications for monotherapy and for brachytherapy as a boost to external beam radiation therapy (EBRT) are presented. It is suggested that each of these techniques has attributes that advocates for one or the other. First, they represent the extreme ends of the spectrum with respect to dose rate and fractionation, and therefore have inherently different radiobiological properties. Low-dose-rate brachytherapy has the great advantage of being practically a one-time procedure, and enjoys a long-term follow-up database supporting its excellent outcomes and low morbidity. Low-dose-rate brachytherapy has been a gold standard for prostate brachytherapy in low risk patients since many years. On the other hand, HDR is a fairly invasive procedure requiring several sessions associated with a brief hospital stay. Although lacking in significant long-term data, it possesses the technical advantage of control over its postimplant dosimetry (by modulating the source dwell time and position), which is absent in LDR brachytherapy. This important difference in dosimetric control allows HDR doses to be escalated safely, a flexibility that does not exist for LDR brachytherapy. Conclusions Radiobiological models support the current clinical evidence for equivalent outcomes in localized prostate cancer with either LDR or HDR brachytherapy, using current dose regimens. At present, all available clinical data regarding these two techniques suggests that they are equally effective, stage for stage, in providing high tumor control rates. PMID:23634153

  12. 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.

  13. 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 that of 131Cs (9.7 days), because the advantage of the longer 103Pd decay half-life was negated by the lower effective energy of the photons it emits (~21 keV compared to ~30.4 keV for 131Cs). In addition, the impact of edema could be reduced or enhanced by differences in the tumor characteristics (e.g. potential tumor doubling time or the ?/? ratio), and the effect of these factors varied for the different radioactive sources. There is a clear need to consider the effects of prostate edema during the planning and evaluation of permanent interstitial brachytherapy treatments for prostate cancer.

  14. Coherence-based photoacoustic imaging of brachytherapy seeds implanted in a canine prostate

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    Visualization of individual brachytherapy seed locations assists with intraoperative updates to brachytherapy treatment plans. Photoacoustic imaging is advantageous when compared to current ultrasound imaging methods, due to its superior sensitivity to metal surrounded by tissue. However, photoacoustic images suffer from poor contrast with insufficient laser fluence. A short-lag spatial coherence (SLSC) beamformer was implemented to enhance these low-contrast photoacoustic signals. Photoacoustic imaging was performed with a transrectal ultrasound probe and an optical fiber surrounded by a light-diffusing sheath, placed at a distance of approximately 4-5 mm from the location of seeds implanted in an in vivo canine prostate. The average energy density through the tip of the sheath was varied from 8 to 167 mJ/cm2. When compared to a fast Fourier transform (FFT)- based reconstruction method, the mean contrast and signal-to-noise ratios were improved by up to 22 dB and a factor of 4, respectively, with the SLSC beamformer (12% of the receive aperture elements were included in the short-lag sum). Image artifacts that were spatially coherent had spatial frequency spectra that were quadrantally symmetric about the origin, while the spatial frequency spectra of the seed signals possessed diagonal symmetry. These differences were utilized to reduce artifacts by 9-14 dB after applying a bandpass filter with diagonal symmetry. Results indicate that advanced methods, such as SLSC beamforming or frequency-based filters, hold promise for intraoperative localization of prostate brachytherapy seeds

  15. 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

  16. 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.

  17. 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.

  18. Dosimetric Impact of Interfraction Catheter Movement in High-Dose Rate Prostate Brachytherapy

    SciTech Connect

    Foster, William; Cunha, J. Adam M.; Hsu, I.-Chow; Weinberg, Vivan; Krishnamurthy, Devan; Pouliot, Jean

    2011-05-01

    Purpose: To evaluate the impact of interfraction catheter movement on dosimetry in prostate high-dose-rate (HDR) brachytherapy. Methods and Materials: Fifteen patients were treated with fractionated HDR brachytherapy. Implants were performed on day 1 under transrectal ultrasound guidance. A computed tomography (CT) scan was performed. Inverse planning simulated annealing was used for treatment planning. The first fraction was delivered on day 1. A cone beam CT (CBCT) was performed on day 2 before the second fraction was given. A fusion of the CBCT and CT was performed using intraprostatic gold markers as landmarks. Initial prostate and urethra contours were transferred to the CBCT images. Bladder and rectum contours were drawn, and catheters were digitized on the CBCT. The planned treatment was applied to the CBCT dataset, and dosimetry was analyzed and compared to the initial dose distribution. This process was repeated after a reoptimization was performed, using the same constraints used on day 1. Results: Mean interfraction catheter displacement was 5.1 mm. When we used the initial plan on day 2, the mean prostate V100 (volume receiving 100 Gy or more) decreased from 93.8% to 76.2% (p < 0.01). Rectal V75 went from 0.75 cm{sup 3} to 1.49 cm{sup 3} (p < 0.01). A reoptimization resulted in a mean prostate V100 of 88.1%, closer to the initial plan (p = 0.05). Mean rectal V75 was also improved with a value of 0.59 cm{sup 3}. There was no significant change in bladder and urethra dose on day 2. Conclusions: A mean interfraction catheter displacement of 5.1 mm results in a significant decrease in prostate V100 and an increase in rectum dose. A reoptimization before the second treatment improves dose distribution.

  19. Salvage brachytherapy in prostate local recurrence after radiation therapy: predicting factors for control and toxicity

    PubMed Central

    2014-01-01

    Purpose To evaluate efficacy and toxicity after salvage brachytherapy (BT) in prostate local recurrence after radiation therapy. Methods and materials Between 1993 and 2007, we retrospectively analyzed 56 consecutively patients (pts) undergoing salvage brachytherapy. After local biopsy-proven recurrence, pts received 145 Gy LDR-BT (37 pts, 66%) or HDR-BT (19 pts, 34%) in different dose levels according to biological equivalent doses (BED2 Gy). By the time of salvage BT, only 15 pts (27%) received ADT. Univariate and multivariate analyses were performed to identify predictors of biochemical control and toxicities. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities were graded using Common Terminology Criteria for Adverse Events (CTCv3.0). Results Median follow-up after salvage BT was 48 months. The 5-year FFbF was 77%. HDR and LDR late grade 3 GU toxicities were observed in 21% and 24%. Late grade 3 GI toxicities were observed in 2% (HDR) and 2.7% (LDR). On univariate analysis, pre-salvage prostate-specific antigen (PSA)?>?10 ng/ml (p?=?0.004), interval to relapse after initial treatment?Prostate BT is an effective salvage modality in some selected prostate local recurrence patients after radiation therapy. Even, we provide some potential predictors of biochemical control and toxicity for prostate salvage BT, further investigation is recommended. PMID:24885287

  20. 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.

  1. 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 BT.

  2. Permanent 125I-seed prostate brachytherapy: early prostate specific antigen value as a predictor of PSA bounce occurrence

    PubMed Central

    2012-01-01

    Purpose To evaluate predictive factors for PSA bounce after 125I permanent seed prostate brachytherapy and identify criteria that distinguish between benign bounces and biochemical relapses. Materials and methods Men treated with exclusive permanent 125I seed brachytherapy from November 1999, with at least a 36 months follow-up were included. Bounce was defined as an increase ? 0.2 ng/ml above the nadir, followed by a spontaneous return to the nadir. Biochemical failure (BF) was defined using the criteria of the Phoenix conference: nadir +2 ng/ml. Results 198 men were included. After a median follow-up of 63.9 months, 21 patients experienced a BF, and 35.9% had at least one bounce which occurred after a median period of 17 months after implantation (4-50). Bounce amplitude was 0.6 ng/ml (0.2-5.1), and duration was 13.6 months (4.0-44.9). In 12.5%, bounce magnitude exceeded the threshold defining BF. Age at the time of treatment and high PSA level assessed at 6 weeks were significantly correlated with bounce but not with BF. Bounce patients had a higher BF free survival than the others (100% versus 92%, p = 0,007). In case of PSA increase, PSA doubling time and velocity were not significantly different between bounce and BF patients. Bounces occurred significantly earlier than relapses and than nadir + 0.2 ng/ml in BF patients (17 vs 27.8 months, p < 0.0001). Conclusion High PSA value assessed 6 weeks after brachytherapy and young age were significantly associated to a higher risk of bounces but not to BF. Long delays between brachytherapy and PSA increase are more indicative of BF. PMID:22449081

  3. Combination of 5?-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 5?-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

  4. Brachytherapy

    MedlinePLUS

    ... high-dose rate (HDR). Permanent brachytherapy , also called seed implantation, involves placing radioactive seeds or pellets (about the size of a grain ... the implants eventually diminishes to nothing. The inactive seeds then remain in the body, with no lasting ...

  5. Influence of zonal dosimetry on prostate brachytherapy outcomes

    PubMed Central

    Hong, Cheng William; Reddy, Chandana A.; Wilkinson, D. Allan; Klein, Eric A.

    2015-01-01

    Purpose To examine the influence of zone-specific dosimetry on outcomes during permanent prostate implantation (PI), where the peripheral zone (PZ) and transitional zone (TZ) may receive varying radiation doses. Material and methods Four hundred and sixteen patients treated with I-125 PI (target dose: 144 Gy) between 1996 and 2003 were included in this Institutional Review Board (IRB) approved, retrospective analysis. Whole prostate (WP), TZ, and PZ were contoured, and zone-specific D90 and V100 were computed. Their influence on biochemical failure (BF) was evaluated using Cox proportional hazards analysis. Results The median age and initial prostate-specific antigen (PSA) was 68 years and 6.1 ng/ml, respectively, and the median follow-up time was 8.8 years. There were 329 subjects with Gleason score (GS) 6 disease (79.1%), and 82 subjects had GS 7 disease (19.7%). Androgen deprivation therapy (ADT) was used in 20.4% of patients. Median D90 and V100% in the WP, PZ, and TZ were 141.2 Gy, 156.1 Gy, and 134.5 Gy; and 88.8%, 93.3%, and 84.2%, respectively. Ten-year rates for biochemical recurrence-free survival, distant metastasis-free survival, and prostate cancer-specific mortality were 82.4%, 92.4%, and 0.97% respectively. Only initial PSA, GS7+ disease, ADT, and PSA frequency were significant on multivariate analysis. Ten-year rates of grade 3 or higher GU and GI toxicity was 10.9% and 1.8%, respectively. TZ V200 and TZ V300 were significantly associated with late genitourinary toxicity. Conclusions The TZ received significantly lower doses of radiation compared to the PZ. On multivariate analysis, no dosimetric parameter was associated with efficacy. Higher TZ doses may be associated with higher late GU toxicity without improving efficacy. PMID:25829932

  6. Biomaterial characteristics and application of silicone rubber and PVA hydrogels mimicked in organ groups for prostate brachytherapy.

    PubMed

    Li, Pan; Jiang, Shan; Yu, Yan; Yang, Jun; Yang, Zhiyong

    2015-09-01

    It is definite that transparent material with similar structural characteristics and mechanical properties to human tissue is favorable for experimental study of prostate brachytherapy. In this paper, a kind of transparent polyvinyl alcohol (PVA) hydrogel and silicone rubber are developed as suitable substitutions for human soft tissue. Segmentation and 3D reconstruction of medical image are performed to manufacture the mould of organ groups through rapid prototyping technology. Micro-structure observation, force test and CCD deformation test have been conducted to investigate the structure and mechanical properties of PVA hydrogel used in organ group mockup. Scanning electron microscope (SEM) image comparison results show that PVA hydrogel consisting of 3 g PVA, 17 g de-ionized water, 80 g dimethyl-sulfoxide (DMSO), 4 g NaCl, 1.5 g NaOH, 3 g epichlorohydrin (ECH) and 7 freeze/thaw cycles reveals similar micro-structure to human prostate tissue. Through the insertion force comparison between organ group mockup and clinical prostate brachytherapy, PVA hydrogel and silicone rubber are found to have the same mechanical properties as prostate tissue and muscle. CCD deformation test results show that insertion force suffers a sharp decrease and a relaxation of tissue deformation appears when needle punctures the capsule of prostate model. The results exhibit that organ group mockup consisting of PVA hydrogel, silicone rubber, membrane and agarose satisfies the needs of prostate brachytherapy simulation in general and can be used to mimic the soft tissues in pelvic structure. PMID:26042767

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Predictive Factors for Acute and Late Urinary Toxicity After Permanent Prostate Brachytherapy: Long-Term Outcome in 712 Consecutive Patients

    SciTech Connect

    Keyes, Mira Miller, Stacy; Moravan, Veronika; Pickles, Tom; McKenzie, Michael; Pai, Howard; Liu, Mitchell; Kwan, Winkle; Agranovich, Alexander; Spadinger, Ingrid; Lapointe, Vincent; Halperin, Ross; Morris, W. James

    2009-03-15

    Purpose: To describe the frequency of acute and late Radiation Therapy Oncology Group (RTOG) urinary toxicity, associated predictive factors, and resolution of International Prostate Symptom Score (IPSS) in 712 consecutive prostate brachytherapy patients. Methods and Materials: Patients underwent implantation between 1998 and 2003 (median follow-up, 57 months). The IPSS and RTOG toxicity data were prospectively collected. The patient, treatment, and implant factors were examined for an association with urinary toxicity. The time to IPSS resolution was examined using Kaplan-Meier curves, and multivariate modeling of IPSS resolution was done using Cox proportional hazards regression analysis. Logistic regression analysis was used to examine the factors associated with urinary toxicity. Results: The IPSS returned to baseline at a median of 12.6 months. On multivariate analysis, patients with a high baseline IPSS had a quicker resolution of their IPSS. Higher prostate D90 (dose covering 90% of the prostate), maximal postimplant IPSS, and urinary retention slowed the IPSS resolution time. The rate of the actuarial 5-year late urinary (>12 months) RTOG Grade 0, 1, 2, 3, and 4 was 32%, 36%, 24%, 6.2%, and 0.1%, respectively. At 7 years, the prevalence of RTOG Grade 0-1 was 92.5%. Patients with a larger prostate volume, greater number of needles, greater baseline IPSS, and use of hormonal therapy had more acute toxicity. On multivariate analysis, the significant predictors for late greater than or equal to RTOG toxicity 2 were a greater baseline IPSS, maximal postimplant IPSS, presence of acute toxicity, and higher prostate V150 (volume of the prostate covered by 150% of the dose). More recently implanted patients had less acute urinary toxicity and patients given hormonal therapy had less late urinary toxicity (all p < 0.02). Conclusion: Most urinary symptoms resolved within 12 months after prostate brachytherapy, and significant long-term urinary toxicity was very low. Refined patient selection and greater technical experience in prostate brachytherapy were associated with less urinary toxicity.

  12. 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.

  13. 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.

  14. High-Dose-Rate Monotherapy: Safe and Effective Brachytherapy for Patients With Localized Prostate Cancer

    SciTech Connect

    Demanes, D. Jeffrey; Martinez, Alvaro A.; Ghilezan, Michel; Hill, Dennis R.; Schour, Lionel; Brandt, David; Gustafson, Gary

    2011-12-01

    Purpose: High-dose-rate (HDR) brachytherapy used as the only treatment (monotherapy) for early prostate cancer is consistent with current concepts in prostate radiobiology, and the dose is reliably delivered in a prospectively defined anatomic distribution that meets all the requirements for safe and effective therapy. We report the disease control and toxicity of HDR monotherapy from California Endocurietherapy (CET) and William Beaumont Hospital (WBH) in low- and intermediate-risk prostate cancer patients. Methods and Materials: There were 298 patients with localized prostate cancer treated with HDR monotherapy between 1996 and 2005. Two biologically equivalent hypofractionation protocols were used. At CET the dose was 42 Gy in six fractions (two implantations 1 week apart) delivered to a computed tomography-defined planning treatment volume. At WBH the dose was 38 Gy in four fractions (one implantation) based on intraoperative transrectal ultrasound real-time treatment planning. The bladder, urethral, and rectal dose constraints were similar. Toxicity was scored with the National Cancer Institute Common Toxicity Criteria for Adverse Events version 3. Results: The median follow-up time was 5.2 years. The median age of the patients was 63 years, and the median value of the pretreatment prostate-specific antigen was 6.0 ng/mL. The 8-year results were 99% local control, 97% biochemical control (nadir +2), 99% distant metastasis-free survival, 99% cause-specific survival, and 95% overall survival. Toxicity was scored per event, meaning that an individual patient with more than one symptom was represented repeatedly in the morbidity data table. Genitourinary toxicity consisted of 10% transient Grade 2 urinary frequency or urgency and 3% Grade 3 episode of urinary retention. Gastrointestinal toxicity was <1%. Conclusions: High disease control rates and low morbidity demonstrate that HDR monotherapy is safe and effective for patients with localized prostate cancer.

  15. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) Practice Guideline for the Transperineal Permanent Brachytherapy of Prostate Cancer

    SciTech Connect

    Rosenthal, Seth A.; Bittner, Nathan H.J.; 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 brachtherapy 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.

  16. [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 for both techniques. The decrease was larger for LS technique, but the difference between techniques was not significant at this patient number. The dose distribution was more homogenous, but the conformality was worse at four-week plans. PMID:26035163

  17. 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.

  18. 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 provide potential predictors of biochemical control for prostate salvage HDRB.

  19. 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.

  20. 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.

  1. 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-quality brachytherapy for low, intermediate, and high-risk patients. These results compare favorably to alternative treatment modalities. In particular, our MFS and CSS rates for high-risk patients appear superior to those of published radical prostatectomy series.

  2. 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 ? (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

  3. 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 ?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

  4. 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.

  5. 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.

  6. 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 isotopes. Conclusion: High-dose regions do not appear to affect cancer control rates, as long as >90% of the prostate volume is covered by the prescription dose.

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

    PubMed

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

    2015-07-21

    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. PMID:26118956

  8. 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.

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

    E-print Network

    Gorissen, Bram L; Hoffmann, Aswin L

    2014-01-01

    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 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 seconds, which confirms earlier results. We propose an iterative procedure for QP that allows to prescribe the target dose as an interval, while retaining independence between the solution time and the number of dose calculation points. This iter...

  10. 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 useful marker for aggressiveness of localized prostate cancer. A larger study will be necessary to further confirm our hypothesis.

  11. 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. PMID:26061145

  12. 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.

  13. 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.

  14. 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.

  15. Comparison Between High and Low Source Activity Seeds for I-125 Permanent Seed Prostate Brachytherapy

    SciTech Connect

    Masucci, Giuseppina Laura; Donath, David; Tetreault-Laflamme, Audrey; Carrier, Jean-Francois; Hervieux, Yannick; Larouche, Renee Xaviere; Bahary, Jean-Paul; Taussky, Daniel

    2010-11-01

    Purpose: To compare low (mean 0.44, SD {+-} 0.0163 mCi) with high source activity (0.61 {+-} 0.0178 mCi) in I{sup 125} permanent seed brachytherapy regarding seed loss, dosimetric outcome, and toxicity. Methods and Materials: The study included 199 patients with prostate cancer treated by permanent seed brachytherapy alone: the first 105 with seeds of lower activity (first cohort), the following 94 with higher seed activity (second cohort). The V100, V150, V200, and D90 were analyzed on the CT scan 30 days after implantation (CTD30). The V100, V150, and D2 of the rectum were also calculated on CTD30. Seed loss was determined 30 days after implantation. Urinary toxicity was measured with the International Prostate Symptom Score (IPSS) questionnaire. Results: Lower seed activity was associated with lower V150 and V200 (p = 0.01 and p {<=} 0.001, respectively) on CTD30. More patients had a V100 <90% and D90 <140 Gy in the lower activity cohort (p = 0.098 for D90 and p = 0.029 for V100) on CTD30. There was no difference between cohorts in dose to the rectum (p = 0.325-0.516) or difference in patients' IPSS score from baseline (p = 0.0.117-0.618), although there was a trend toward more urinary toxicity at 4 and 8 months for high activity seeds. Seed loss as a percentage of implanted seeds was not different (p = 0.324). Conclusions: Higher seed activity (I{sup 125} {>=} 0.6 mCi) results in at least equal V100 and D90 on CTD30. However, dose inhomogeneity and a trend toward more urinary toxicity at 4 and 8 months after treatment may lead to a higher long-term urinary complications.

  16. 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.

  17. 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.

  18. 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 functioning, and brachytherapy caused moderate urinary irritation. These results provide relevant information for clinical decision making.

  19. Influence of body mass index and periprostatic fat on rectal dosimetry in permanent seed prostate brachytherapy

    PubMed Central

    2014-01-01

    Purpose We examined the influence of body mass index (BMI) and body fat distribution on rectal dose in patients treated with permanent seed brachytherapy for localized prostate cancer. Methods and materials We analyzed 213 patients treated with I125 seed brachytherapy for localized prostate cancer. BMI and rectal dosimetry data for all patients were available. Data on visceral and subcutaneous fat distribution at the level of the iliac crest (n?=?140) as well as the distribution of periprostatic and subcutaneous fat at the symphysis pubis level were obtained (n?=?117). Fat distribution was manually contoured on CT on day 30 after brachytherapy. The correlation between BMI, fat distribution and rectal dose (R100 (in cc), R150 (cc), D2 (Gy)) was analyzed using the Spearman correlation coefficient. Differences in rectal dose between tertiles of body fat distribution were calculated using nonparametric tests. Results Periprostatic adipose was only weakly correlated with BMI (r?=?0.0.245, p?=?0.008) and only weakly correlated with the other fat measurements (r?=?0.31-0.37, p?1.3 cc (23% of patients) had less visceral fat (p?=?0.004), less subcutaneous fat at the level of the iliac crest (p?=?0.046) and a lower BMI (26.8 kg/m2 vs. 28.5 kg/m2, p?=?0.02) than patients with an R100 of <1.3 cc. Results were very similar when comparing an R100 of >1.0 cc (34% of patients) across the tertiles. None of the tested linear regression models were predictive (max 12%) of dose to the rectum. Conclusion Dose to the rectum is dependent on BMI and body fat distribution. Periprostatic fat does not influence rectal dose. Dose to the rectum remains difficult to predict and depends on many factors, one of which is body fat distribution. PMID:24731303

  20. 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.

  1. High-dose-rate brachytherapy boost for prostate cancer: rationale and technique

    PubMed Central

    2014-01-01

    High-dose-rate brachytherapy (HDR) is a method of conformal dose escalation to the prostate. It can be used as a local boost in combination with external beam radiotherapy, with a high degree of efficacy and low rate of long term toxicity. Data consistently reports relapse free survival rates of greater than 90% for intermediate risk patients and greater than 80% for high risk. Results are superior to those achieved with external beam radiotherapy alone. A wide range of dose and fractionation is reported, however, we have found that a single 15 Gy HDR combined with hypofractionated radiotherapy to a dose of 37.5 Gy in 15 fractions is well tolerated and is associated with a long term relapse-free survival of over 90%. Either CT-based or trans-rectal ultrasound-based planning may be used. The latter enables treatment delivery without having to move the patient with risk of catheter displacement. We have found it to be an efficient and quick method of treatment, allowing catheter insertion, planning, and treatment delivery to be completed in less than 90 minutes. High-dose-rate boost should be considered the treatment of choice for many men with high and intermediate risk prostate cancer. PMID:25337138

  2. 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.

  3. 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 minimum separation of the seeds for GE at the demonstration TE of 11 ms was found to be between 3 and 4.5 mm for 1.5 T and between 4.5 and 6 mm for 3 T. These GE artifact dimensions will scale down with TE and, as this happens, approach the dimensions of the FSE artifacts given above.

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

    PubMed

    Kukie?ka, Andrzej M; Strnad, Vratislav; Stauffer, Paul; D?browski, Tomasz; Hetna?, Marcin; Nahajowski, Damian; Walasek, Tomasz; Brandys, Piotr; Matys, Robert

    2015-06-01

    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

  5. 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; D?browski, Tomasz; Hetna?, 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

  6. 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 of peripheral seeds involved, but lateral shearing movement can have greater consequences for local dose coverage.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. Bipolar button-electrode plasma vaporization of the prostate: An effective option for patients with post-brachytherapy retention

    PubMed Central

    LIN, YIWEI; LIU, BEN; XIE, LIPING

    2015-01-01

    Urinary retention is a common urinary complication following brachytherapy for prostate cancer. When conservative therapy has failed, surgical intervention, such as transurethral resection of the prostate (TURP), is performed. In the present case, it was found that conventional bipolar TURP was an inappropriate choice of therapy, since the electrical loop could easily rupture and discharge sparks when encountering the seeds intraoperatively; however, bipolar button-electrode plasma vaporization of the prostate was proven to be a much safer technique. The ‘button-type’ electrode, which has a larger contacting surface, was firm enough to tolerate the transient high levels of energy generated by the short circuit and enable the safe completion of the procedure.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Genitourinary Toxicity After High-Dose-Rate (HDR) Brachytherapy Combined With Hypofractionated External Beam Radiotherapy for Localized Prostate Cancer: An Analysis to Determine the Correlation Between Dose-Volume Histogram Parameters in HDR Brachytherapy and Severity of Toxicity

    SciTech Connect

    Ishiyama, Hiromichi Kitano, Masashi; Satoh, Takefumi; Kotani, Shouko; Uemae, Mineko; Matsumoto, Kazumasa; Okusa, Hiroshi; Tabata, Ken-ichi; Baba, Shiro; Hayakawa, Kazushige

    2009-09-01

    Purpose: To evaluate the severity of genitourinary (GU) toxicity in high-dose-rate (HDR) brachytherapy combined with hypofractionated external beam radiotherapy (EBRT) for prostate cancer and to explore factors that might affect the severity of GU toxicity. Methods and Materials: A total of 100 Japanese men with prostate cancer underwent {sup 192}Ir HDR brachytherapy combined with hypofractionated EBRT. Mean (SD) dose to 90% of the planning target volume was 6.3 (0.7) Gy per fraction of HDR. After 5 fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administrated. The urethral volume receiving 1-15 Gy per fraction in HDR brachytherapy (V1-V15) and the dose to at least 5-100% of urethral volume in HDR brachytherapy (D5-D100) were compared between patients with Grade 3 toxicity and those with Grade 0-2 toxicity. Prostate volume, patient age, and International Prostate Symptom Score were also compared between the two groups. Results: Of the 100 patients, 6 displayed Grade 3 acute GU toxicity, and 12 displayed Grade 3 late GU toxicity. Regarding acute GU toxicity, values of V1, V2, V3, and V4 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Regarding late GU toxicity, values of D70, D80, V12, and V13 were significantly higher in patients with Grade 3 toxicity than in those with Grade 0-2 toxicity. Conclusions: The severity of GU toxicity in HDR brachytherapy combined with hypofractionated EBRT for prostate cancer was relatively high. The volume of prostatic urethra was associated with grade of acute GU toxicity, and urethral dose was associated with grade of late GU toxicity.

  1. 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.

  2. The investigation of prostatic calcifications using ?-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 (?-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 in the patient’s individual treatment. These factors include the number, size, composition and spatial distribution of calcifications in the prostate as well as the distribution of brachytherapy seeds.

  3. The investigation of prostatic calcifications using ?-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 (?-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 in the patient's individual treatment. These factors include the number, size, composition and spatial distribution of calcifications in the prostate as well as the distribution of brachytherapy seeds. PMID:25984817

  4. 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 the estimated projection position was found to be 0.95 mm in the imaging (detector) plane, resulting in a maximum source positioning estimation error of 1.48 mm.Conclusions: HDR BrachyView is a feasible design for real-time source tracking in HDR prostate brachytherapy. It is capable of resolving the source position within a subsecond dwell time. In combination with anatomical information obtained from transrectal ultrasound imaging, HDR BrachyView adds a significant quality assurance capability to HDR brachytherapy treatment systems.

  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 the large target margin and avoiding dose dead zones for prostate cancer treatment. 1) National Natural Science Foundation of People's Republic of China (No. 51175373); 2) New Century Educational Talents Plan of Chinese Education Ministry (NCET-10-0625); 3) Scientific and Technological Major Project, Tianjin (No. 12ZCDZSY10600)

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

    PubMed Central

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

    2011-01-01

    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 was 592 seeds, which implied that several prostate seed implantation cases would be possible without encountering any critical failure. The shape parameter for the MTBF was 0.3859 (<1), suggesting a positive reliability growth of this robotic system. At 95% confidence, the reliability for deposition of 65 seeds was more than 90%. Conclusions: Analyses of failure mode strongly indicated a gradual improvement of reliability of this autonomous robotic system. High MTBF implied that several prostate seed implant cases would be possible without encountering any critical failure. PMID:21361179

  7. 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.

  8. 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.

  9. 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 in the operating room rather than requiring additional therapy afterwards. This research was supported in part by the National Institutes of Health/National Cancer Institute (NIH/NCI) under grant 2R44CA099374 and grant 1R01CA151395, and in part by the Department of Defense (DoD) under grant W81XWH-05-1-0407.

  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-risk prostate cancer, administered using a single implant over 2 days, is feasible and has acceptable acute and late toxicities. Further follow-up is still required to better evaluate the efficacy of such treatment.

  11. Bimodal Imaging of Inflammation with SPECT/CT and MRI Using Iodine-125 Labeled VCAM1 Targeting Microparticle Conjugates

    E-print Network

    Jones, Peter JS

    Bimodal Imaging of Inflammation with SPECT/CT and MRI Using Iodine-125 Labeled VCAM1 Targeting for Advanced Biomedical Imaging (CABI) and Division of Medicine and Department of Chemistry and Institute and an early feature of several neurological conditions. Here, we describe bimodal in vivo imaging

  12. 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 overestimating V150 and V200 by 1.6% and 1.3%, respectively. Urethral and rectal dose quantifiers tended to be underestimated by the 1D calculation. The most pronounced differences were in the urethral D30 and rectal D2cc, which rose by 3.8 and 1.9 Gy, respectively, using the 2D calculation. The total volume of the 100% isodose region as a percentage of the prostate volume was found to increase by 0.4%. Conclusions: Stranded seeds in the supine patient are not oriented in a uniformly random manner, nor are they aligned along the axis of the CT scanner. Instead, this study identified a consistent anterior pitch that is likely attributable to differences in patient pose between implant and CT imaging. The angle of the ultrasound probe with respect to the patient during implant may have also been a contributing factor. The dose metrics derived using the 1D formalism were found to be within 2%, on average, of those derived using the 2D formalism. For greater accuracy, 2D dosimetry can be pursued using the strand-fitting method described in this work. If a 1D representation is used, integrating over the empirically determined seed orientation density reported here may be more appropriate than assuming that seed inclinations are distributed uniformly.

  13. 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

  14. 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.

  15. 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 such as air, bone, or lungs, produced variations between both phantoms which were at most 35% in the considered organ equivalent doses. Finally, effective doses per clinical absorbed dose from IMRT and proton therapy were comparable to those from both brachytherapy sources, with brachytherapy being advantageous over external beam radiation therapy for the furthest organs. Conclusions: A database of organ equivalent doses when applying HDR brachytherapy to the prostate with either {sup 60}Co or {sup 192}Ir is provided. According to physical considerations, {sup 192}Ir is dosimetrically advantageous over {sup 60}Co sources at large distances, but not in the closest organs. Damage to distant healthy organs per clinical absorbed dose is lower with brachytherapy than with IMRT or protons, although the overall effective dose per Gy given to the prostate seems very similar. Given that there are several possible fractionation schemes, which result in different total amounts of therapeutic absorbed dose, advantage of a radiation treatment (according to equivalent dose to healthy organs) is treatment and facility dependent.

  16. 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 2 or greater rectal toxicity.

  17. Impact of oedema on implant geometry and dosimetry for temporary high dose rate brachytherapy of the prostate.

    PubMed

    Kiffer, John D; Schumer, Wendy A; Mantle, Carmel A; McKenzie, Brett J; Feigen, Malcolm; Quong, George G; Waterman, Frank M

    2003-06-01

    The optimal timing of dosimetry for permanent seed prostatic implants remains contentious given the half life of post-implant oedema resolution. The aim of this study was to establish whether prostatic oedematous change over the duration of a temporary high dose rate (HDR) interstitial brachytherapy (BR) boost would result in significant needle displacement, and whether this change in geometry would influence dosimetry. Two CT scans, one for dosimetric purposes on the day of the implant and the second just prior to implant removal, were obtained for four patients receiving transperineal interstitial prostate brachytherapy. The relative changes in cross-sectional dimensions of the implants were calculated by establishing the change in mean radial distance (MRD) of the needle positions from the geometric centre of the implant for each patient's pair of CT studies. The treatment plan, as calculated from the first CT scan, was used in the second set of CT images to allow a comparison of dose distribution. The percentage change in MRD over the duration of the temporary implants ranged from -1.91% to 1.95%. The maximum change in estimated volume was 3.94%. Dosimetric changes were negligible. In the four cases studied, the degree of oedematous change and consequent displacement of flexiguide needle positions was negligible and did not impact on the dosimetry. The rate and direction of oedematous change can be extremely variable but on the basis of the four cases studied and the results of a larger recent study, it might not be necessary to re-image patients for dosimetric purposes over the duration of a fractionated HDR BT boost to the prostate where flexiguide needles are utilized. Nevertheless, further investigation with larger patient numbers is required. PMID:12780447

  18. 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.

  19. Inverse planning anatomy-based dose optimization for HDR-brachytherapy of the prostate using fast simulated annealing algorithm and dedicated

    E-print Network

    Pouliot, Jean

    Inverse planning anatomy-based dose optimization for HDR-brachytherapy of the prostate using fast An anatomy-based dose optimization algorithm is developed to automatically and rapidly produce a highly are optimized using an inverse planning simulated annealing algorithm IPSA governed entirely from the anatomy

  20. Robotic Needle Guide for Prostate Brachytherapy: Clinical Testing of Feasibility and Performance

    PubMed Central

    Song, Danny Y; Burdette, Everette C; Fiene, Jonathan; Armour, Elwood; Kronreif, Gernot; Deguet, Anton; Zhang, Zhe; Iordachita, Iulian; Fichtinger, Gabor; Kazanzides, Peter

    2010-01-01

    Purpose Optimization of prostate brachytherapy is constrained by tissue deflection of needles and fixed spacing of template holes. We developed and clinically tested a robotic guide towards the goal of allowing greater freedom of needle placement. Methods and Materials The robot consists of a small tubular needle guide attached to a robotically controlled arm. The apparatus is mounted and calibrated to operate in the same coordinate frame as a standard template. Translation in x and y directions over the perineum ±40mm are possible. Needle insertion is performed manually. Results Five patients were treated in an IRB-approved study. Confirmatory measurements of robotic movements for initial 3 patients using infrared tracking showed mean error of 0.489 mm (SD 0.328 mm). Fine adjustments in needle positioning were possible when tissue deflection was encountered; adjustments were performed in 54/179 (30.2%) needles placed, with 36/179 (20.1%) adjustments of > 2mm. Twenty-seven insertions were intentionally altered to positions between the standard template grid to improve the dosimetric plan or avoid structures such as pubic bone and blood vessels. Conclusions Robotic needle positioning provided a means of compensating for needle deflections as well as the ability to intentionally place needles into areas between the standard template holes. To our knowledge, these results represent the first clinical testing of such a system. Future work will be incorporation of direct control of the robot by the physician, adding software algorithms to help avoid robot collisions with the ultrasound, and testing the angulation capability in the clinical setting. PMID:20729152

  1. 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.

  2. 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.

  3. Intra-operative 3D guidance and edema detection in prostate brachytherapy using a non-isocentric C-arm

    PubMed Central

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

    2015-01-01

    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 treatment planning 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 six 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 over four additional seeds in the six enrolled patients (minimum 1; maximum 9). 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 affect a paradigm shift in clinical practice. Large scale studies and commercialization are currently underway. PMID:21168357

  4. 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 ?,?) and cellular repair (time tr) on a cell population. Radiosensitization was modeled as concentration dependent change in ?,? 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 ? or ? 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 benefit with drug release over weeks. If in-vivo drug concentrations are not able to approach saturation concentration, durations of days is optimal. DOD 1R21CA16977501; A. David Mazzone Awards Program 2012PD164.

  5. Twelve-Month Prostate-Specific Antigen Values and Perineural Invasion as Strong Independent Prognostic Variables of Long-Term Biochemical Outcome After Prostate Seed Brachytherapy

    SciTech Connect

    Ding, William; Lee, John; Chamberlain, David; Cunningham, James; Yang Lixi; Tay, Jonathan

    2012-11-15

    Purpose: To determine whether post-treatment prostate-specific antigen (ptPSA) values at 12 months and other clinical parameters predict long-term PSA relapse-free survival (PRFS) following prostate seed brachytherapy. Methods and Materials: Records of 204 hormone-naieve patients with localized adenocarcinoma of the prostate treated at St. Mary's Regional Medical Center in Reno, NV, and at Carson Tahoe Regional Medical Center in Carson City, NV, between 1998 and 2003, using I-125 or Pd-103 seed brachytherapy, were retrospectively analyzed. Treatment planning was done using a preplanned, modified peripheral loading technique. A total of 185 of 204 patients had PSA records at 12 months after implant. Variables included were age, initial pretreatment PSA, Gleason score, T stage, National Comprehensive Cancer Network (NCCN) risk group (RG), perineural invasion (PNI), external beam boost, dose, and ptPSA levels at 12 months with cutpoints at {<=}1, 1.01 to 2.00, 2.01 to 3.00, and >3.00 ng/ml. Results: Median follow-up was 80 months, and median age was 69 years. The numbers of patients stratified by NCCN low, intermediate, and high RG were 110:65:10, respectively. Monotherapy and boost prescription doses were 145 Gy and 110 Gy for I-125, and 125 Gy and 100 Gy for Pd-103 seeds, respectively. The median dose (D90) was 95.4% of the prescribed dose. The 5-year PRFS at the 12-months ptPSA levels of {<=}1, 1.01 to 2.00, 2.01 to 3.00, and >3.00 ng/ml were 98.5%, 85.7%, 61.5%, and 22.2%, respectively. The 10-year PRFS at the 12-months ptPSA levels of {<=}1 and 1.01 to 2.00 ng/ml were 90.5% and 85.7%, respectively. In multivariate analysis, both ptPSA and PNI were significant independent predictors of PRFS. Hazard ratios (HR) for ptPSA levels at {<=}1, 1.01 to 2.00, 2.01 to 3.00, and >3.00 ng/ml at 12 months were 1, 4.96, 27.57, and 65.10, respectively. PNI had an HR of 6.1 (p = 0.009). Conclusions: Presence of PNI and ptPSA values at 12 months are strong prognostic variables for long-term PRFS after definitive prostate brachytherapy seed implantation.

  6. Safety and efficacy of salvage low-dose-rate brachytherapy for prostate bed recurrences following radical prostatectomy

    PubMed Central

    Kumar, Aryavarta M.S.; Smith, Kristin L.; Reddy, Chandana A.; Stephans, Kevin L.; Klein, Eric A.

    2015-01-01

    Purpose To report efficacy in our series of nodular recurrences in the post-surgical bed that underwent salvage low-dose-rate (LDR) brachytherapy. Material and methods Patients with radical prostatectomy (RP) who had biochemical failure with nodular recurrence detected by DRE, ultrasound, and pelvic CT and then salvaged with LDR 125I brachytherapy were included. Nodular recurrences were biopsy confirmed adenocarcinoma, and patients had no evidence of nodal or distant metastasis on imaging including bone scan. Follow up was at least every 6 months with a serial prostate specific antigen (PSA). Results Twelve patients had salvage LDR brachytherapy with median age 69 years (range 59-86) and median pre-salvage PSA of 4.22 ng/ml. Nodule biopsy Gleason score was 7, 8, or undifferentiated. Median rectal V100 was 0.00 cc. Compared to pre-salvage, patients reported no additional genitourinary (GU) toxicity. After a median 35 months post-salvage follow up (range 10-81 months), patients had a median PSA nadir of 0.72 ng/ml (range 0.01-22.4). At 6 months post salvage, 90% of patients had a PSA below pre-salvage levels. At last follow up, 4 patients had PSA control. Conclusions There was a trend to improved biochemical relapse free survival for lower Gleason score and pre-salvage PSA, which may be indicative of the lack of or only low volume metastatic disease. LDR brachytherapy is an effective salvage technique and can be considered in well selected patients allowing for dose escalation to the nodular recurrence. PMID:26622225

  7. 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.

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

    SciTech Connect

    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.

  9. 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.

  10. 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.

  11. 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.

  12. 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. PMID:22763006

  13. 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 longer than the center-to-center distance between the first and last seed owing to the finite length of the seeds at the ends of the array. When this occurred, it was necessary to disregard either the most distal or most proximal echo, which produced a 0.5-cm uncertainty in the location of the array in the axial direction. For these reasons, simply localizing the visible echoes in the TRUS images did not guarantee the reliable identification of the seeds. Conclusion: Our results have demonstrated that a high percentage (>85%) of the implanted {sup 125}I seeds can be directly visualized in postimplant TRUS images when the seeds and spacers are linked to preclude seed migration and rotation and when the images are obtained with a high-resolution TRUS probe. Moreover, it is possible to localize 100% of the seeds with the mechanism of linked seeds because the locations of the missing seeds can be determined from the known construction of the arrays.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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, number of skin cancers in the EBRT patients compared with that of the general population.

  19. A comparative study of seed localization and dose calculation on pre- and post-implantation ultrasound and CT images for low-dose-rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Ali, Imad; Algan, Ozer; Thompson, Spencer; Sindhwani, Puneet; Herman, Terence; Cheng, Chih-Yao; Ahmad, Salahuddin

    2009-09-01

    This work investigates variation in the volume of the prostate measured at different stages through the prostate brachytherapy procedure for 30 patients treated with I-125 radioactive seeds. The implanted seeds were localized on post-implantation ultrasound (US) images and the effect of prostate enlargement due to edema on dose coverage for 15 patients was studied. The volume of the prostate was measured at four stages as follows: (a) 2-3 weeks prior to implantation using US imaging, (b) then at the start of the intra-operative prostate brachytherapy procedure on the day of the implant, (c) immediately post-implantation using US imaging in the operating room and (d) finally by CT imaging at nearly 4 weeks post-implantation. Comparative prostate volume studies were performed using US imaging stepper and twister modes. For the purpose of this study, the implanted seeds were localized successfully on post-implant ultrasound twister images, retrospectively. The plans using post-implant US imaging were compared with intra-operative plans on US and plans created on CT images. The prostate volume increases about 10 cm3 on average due to edema induced by needle insertion and seed loading during implantation. The visibility of the implanted seeds on US twister images acquired post-implantation is as good as those on CT images and can be localized and used for dose calculation. The dose coverage represented by parameters such as D90 (dose covering 90% of the volume) and V100 (volume covered by 100% dose) is poorer on plans performed on post-implantation twister US studies than on the intra-operative live plan or the CT scan performed 4 weeks post-operatively. For example, the mean D90 difference on post-implantation US is lower by more than 15% than that on pre-implantation US. The volume enlargement of the prostate due to edema induced by needle insertion and seed placement has a significant effect on the quality of dosimetric coverage in brachytherapy prostate seed implants. Here, we introduced a new approach based on the use of post-implant US twister images to correct for prostate enlargement intra-operatively. Besides the ability to localize the seeds and superior soft tissue visibility, the twister US images include effects of the enlargement of the prostate gland and seed migration during the implantation procedure.

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

    PubMed

    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. PMID:26675313

  1. 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. Successful integration of multi-parametric MR and TRUS prostate images provides a prostate-cancer map for treatment planning, enables accurate dose planning and delivery, and potentially enhances prostate HDR treatment outcome.

  2. Gold marker displacement due to needle insertion during HDR-brachytherapy for treatment of prostate cancer: A prospective cone beam computed tomography and kilovoltage on-board imaging (kV-OBI) study

    PubMed Central

    2012-01-01

    Purpose To evaluate gold marker displacement due to needle insertion during HDR-brachytherapy for therapy of prostate cancer. Patients and methods 18 patients entered into this prospective evaluation. Three gold markers were implanted into the prostate during the first HDR-brachytherapy procedure after the irradiation was administered. Three days after marker implantation all patients had a CT-scan for planning purpose of the percutaneous irradiation. Marker localization was defined on the digitally-reconstructed-radiographs (DRR) for daily (VMAT technique) or weekly (IMRT) set-up error correction. Percutaneous therapy started one week after first HDR-brachytherapy. After the second HDR-brachytherapy, two weeks after first HDR-brachtherapy, a cone-beam CT-scan was done to evaluate marker displacement due to needle insertion. In case of marker displacement, the actual positions of the gold markers were adjusted on the DRR. Results The value of the gold marker displacement due to the second HDR-brachytherapy was analyzed in all patients and for each gold marker by comparison of the marker positions in the prostate after soft tissue registration of the prostate of the CT-scans prior the first and second HDR-brachytherapy. The maximum deviation was 5 mm, 7 mm and 12 mm for the anterior-posterior, lateral and superior-inferior direction. At least one marker in each patient showed a significant displacement and therefore new marker positions were adjusted on the DRRs for the ongoing percutaneous therapy. Conclusions Needle insertion in the prostate due to HDR-brachytherapy can lead to gold marker displacements. Therefore, it is necessary to verify the actual position of markers after the second HDR-brachytherapy. In case of significant deviations, a new DRR with the adjusted marker positions should be generated for precise positioning during the ongoing percutaneous irradiation. PMID:22348595

  3. Long-Term Biochemical and Survival Outcome of 921 Patients Treated With I-125 Permanent Prostate Brachytherapy

    SciTech Connect

    Hinnen, Karel A.; Battermann, Jan J.; Roermund, Joep G.H. van; Moerland, Marinus A.; Juergenliemk-Schulz, Ina M.; Frank, Steven J.; Vulpen, Marco van

    2010-04-15

    Purpose: To assess long-term biochemical and survival outcome after permanent prostate brachytherapy (BT). Methods and Materials: Data on 921 patients, treated with permanent interstitial BT monotherapy between 1989 and 2004 for <=T2c Nx/0 Mx/0 prostate cancer were evaluated. All patients were treated with I-125 seeds (prescription dose 144 Gy). Eighty-five patients with a gland volume >=50cc received 6 months of antiandrogen therapy before treatment. Patients were classified into risk groups with 232 defined as low-, 369 intermediate-, and 320 high-risk disease. The median follow-up was 69 months (range, 4-186 months); mean age was 67 years. Results: Average 5- and 10-year biochemical no evidence of disease (bNED) rates were 79% and 57%. Average 10-year bNED rates by risk group were 88% for low-risk, 61% for intermediate-risk, and 30% for high-risk disease. The average 10-year overall and disease-specific survival rates were 59% and 82%. Ten-year overall and disease-specific survival rates by risk group were, respectively, 68% and 96% for low-risk, and 64% 87% for intermediate-risk, and 49% and 69% for high-risk disease. In multivariate Cox regression analysis, both risk group and treatment era were independent predictors of bNED and survival. Conclusions: These data on long-term survival continue to support the use of I-125 monotherapy for prostate cancer in low-risk patients and, in particular, demonstrate its efficacy in intermediate-risk patients.

  4. 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.

  5. 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.

  6. 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 control following PPB. A BED of >200 Gy with an alpha/beta ratio of 2 yields 96.9% local control rate. Failure to establish local control impacts survival.

  7. Phase II Trial of Combined High-Dose-Rate Brachytherapy and External Beam Radiotherapy for Adenocarcinoma of the Prostate: Preliminary Results of RTOG 0321

    SciTech Connect

    Hsu, I-Chow; Bae, Kyounghwa; Shinohara, Katsuto; Pouliot, Jean; Purdy, James; Ibbott, Geoffrey; Speight, Joycelyn; Vigneault, Eric; Ivker, Robert M.D.; Sandler, Howard M.D.

    2010-11-01

    Purpose: To estimate the rate of late Grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) after treatment with external beam radiotherapy and prostate high-dose-rate (HDR) brachytherapy. Methods and Materials: Each participating institution submitted computed tomography-based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined Stage T1c-T3b prostate cancer were eligible for the present study. All patients were treated with 45 Gy in 25 fractions using external beam radiotherapy and one HDR implant delivering 19 Gy in two fractions. All AEs were graded according to the Common Terminology Criteria for Adverse Events, version 3.0. Late GU/GI AEs were defined as those occurring >9 months from the start of the protocol treatment, in patients with {>=}18 months of potential follow-up. Results: A total of 129 patients from 14 institutions were enrolled in the present study. Of the 129 patients, 125 were eligible, and AE data were available for 112 patients at analysis. The pretreatment characteristics of the patients were as follows: Stage T1c-T2c, 91%; Stage T3a-T3b, 9%; prostate-specific antigen level {<=}10 ng/mL, 70%; prostate-specific antigen level >10 but {<=}20 ng/mL, 30%; and Gleason score 2-6, 10%; Gleason score 7, 72%; and Gleason score 8-10, 18%. At a median follow-up of 29.6 months, three acute and four late Grade 3 GU/GI AEs were reported. The estimated rate of late Grade 3-5 GU and GI AEs at 18 months was 2.56%. Conclusion: This is the first prospective, multi-institutional trial of computed tomography-based HDR brachytherapy and external beam radiotherapy. The technique and doses used in the present study resulted in acceptable levels of AEs.

  8. 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.

  9. 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.

  10. Improved dosimetry in prostate brachytherapy using high resolution contrast enhanced magnetic resonance imaging: a feasibility study

    PubMed Central

    Morancy, Tye; Kaplan, Irving; Qureshi, Muhammad M.; Hirsch, Ariel E.; Rofksy, Neil M.; Holupka, Edward; Oismueller, Renee; Hawliczek, Robert; Helbich, Thomas H.; Bloch, B. Nicolas

    2014-01-01

    Purpose To assess detailed dosimetry data for prostate and clinical relevant intra- and peri-prostatic structures including neurovascular bundles (NVB), urethra, and penile bulb (PB) from postbrachytherapy computed tomography (CT) versus high resolution contrast enhanced magnetic resonance imaging (HR-CEMRI). Material and methods Eleven postbrachytherapy prostate cancer patients underwent HR-CEMRI and CT imaging. Computed tomography and HR-CEMRI images were randomized and 2 independent expert readers created contours of prostate, intra- and peri-prostatic structures on each CT and HR-CEMRI scan for all 11 patients. Dosimetry data including V100, D90, and D100 was calculated from these contours. Results Mean V100 values from CT and HR-CEMRI contours were as follows: prostate (98.5% and 96.2%, p = 0.003), urethra (81.0% and 88.7%, p = 0.027), anterior rectal wall (ARW) (8.9% and 2.8%, p < 0.001), left NVB (77.9% and 51.5%, p = 0.002), right NVB (69.2% and 43.1%, p = 0.001), and PB (0.09% and 11.4%, p = 0.005). Mean D90 (Gy) derived from CT and HR-CEMRI contours were: prostate (167.6 and 150.3, p = 0.012), urethra (81.6 and 109.4, p = 0.041), ARW (2.5 and 0.11, p = 0.003), left NVB (98.2 and 58.6, p = 0.001), right NVB (87.5 and 55.5, p = 0.001), and PB (11.2 and 12.4, p = 0.554). Conclusions Findings of this study suggest that HR-CEMRI facilitates accurate and meaningful dosimetric assessment of prostate and clinically relevant structures, which is not possible with CT. Significant differences were seen between CT and HR-CEMRI, with volume overestimation of CT derived contours compared to HR-CEMRI. PMID:25834576

  11. 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.

  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. Monotherapeutic High-Dose-Rate Brachytherapy for Prostate Cancer: Five-Year Results of an Extreme Hypofractionation Regimen With 54 Gy in Nine Fractions

    SciTech Connect

    Yoshioka, Yasuo; Konishi, Koji; Sumida, Iori; Takahashi, Yutaka; Isohashi, Fumiaki; Ogata, Toshiyuki; Koizumi, Masahiko; Yamazaki, Hideya; Nonomura, Norio; Okuyama, Akihiko; Inoue, Takehiro

    2011-06-01

    Purpose: To evaluate an extreme hypofractionation regimen with 54 Gy in nine fractions provided by high-dose-rate (HDR) brachytherapy as monotherapy for prostate cancer by reporting 5-year clinical results. Methods and Materials: Between 1996 and 2005, 112 patients with localized prostate cancer were treated with HDR brachytherapy without external beam radiotherapy. Of the 112 patients, 15 were considered low risk, 29 intermediate risk, and 68 as high risk. The prescribed dose was uniformly 54 Gy in nine fractions within 5 days. Of the 112 patients, 94 also received hormonal therapy. The median follow-up time was 5.4 years. Results: All the patients safely completed the treatment regimen. The 5-year prostate-specific antigen (PSA) failure-free, local control, disease-free survival, and overall survival rate was 83%, 97%, 87%, and 96%, respectively. The 5-year PSA failure-free rate for low-, intermediate-, and high-risk patients was 85% (95% confidence interval, 66-100%), 93% (95% confidence interval, 83-100%), and 79% (95% confidence interval, 69-89%), respectively. The significant prognostic factors for PSA failure were the initial PSA level (p = .029) and younger age (p = .019). The maximal toxicities observed were Grade 3 using the Common Terminology Criteria for Adverse Events, version 3.0, for both acute and late toxicity (6 and 3 patients had acute and late Grade 3 toxicity, respectively). Late Grade 2 toxicity was observed in 13 patients. Conclusion: Monotherapeutic HDR brachytherapy with an extreme hypofractionation regimen of 54 Gy in nine fractions associated with hormonal therapy was feasible, and its toxicity was acceptable. The interim tumor control rate at a median 5.4 years was promising, even for patients with locally advanced disease. This dose-fractionation scheme might be referred to by other terms, such as stereotactic body radiotherapy. Studies with longer follow-up periods and from multiple institutions are needed to confirm the efficacy of this novel approach.

  15. 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

    PubMed Central

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

    2014-01-01

    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 ultimately may allow US-based real-time intraoperative dosimetry. PMID:25186418

  16. 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 ultimately may allow US-based real-time intraoperative dosimetry.

  17. 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.

  18. 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 corrections in seed positions for the thin seed scans and 3.0 {+-} 1.2 manual corrections in seed positions for the standard seed scans. The average error in seed placement was 1.2 mm for both seed types and the maximum error in seed placement was 2.1 mm for the thin seed scans and 1.8 mm for the standard seed scans. Conclusions: The 9011 thin seeds yielded significantly improved image quality for CT and US images but no significant differences in MR image quality.

  19. 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.

  20. 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 and the secondary endpoints will be all other grades of genitourinary toxicities (grades 1 and 2), gastrointestinal toxicities (grades 1 to 4), prostate-specific antigen (PSA) recurrence-free survival, overall survival, and quality of life. Results Results from this feasibility trial will be available in mid-2016. Conclusions If the results from this feasibility trial show evidence that the sequence of treatment modality does affect the patients’ toxicity profiles, then funding would be sought to conduct a large, multicenter, randomized controlled trial. Trial Registration International Standard Randomized Controlled Trial Number (ISRCTN): 15835424; http://www.isrctn.com/ISRCTN15835424 (Archived by WebCite at http://www.webcitation.org/6Xz7jfg1u). PMID:25926023

  1. 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.

  2. 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.

  3. 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.

  4. 2D Ultrasound and 3D MR Image Registration of the Prostate for Brachytherapy Surgical Navigation.

    PubMed

    Zhang, Shihui; Jiang, Shan; Yang, Zhiyong; Liu, Ranlu

    2015-10-01

    Two-dimensional (2D) ultrasound (US) images are widely used in minimally invasive prostate procedure for its noninvasive nature and convenience. However, the poor quality of US image makes it difficult to be used as guiding utility. To improve the limitation, we propose a multimodality image guided navigation module that registers 2D US images with magnetic resonance imaging (MRI) based on high quality preoperative models. A 2-step spatial registration method is used to complete the procedure which combines manual alignment and rapid mutual information (MI) optimize algorithm. In addition, a 3-dimensional (3D) reconstruction model of prostate with surrounding organs is employed to combine with the registered images to conduct the navigation. Registration accuracy is measured by calculating the target registration error (TRE). The results show that the error between the US and preoperative MR images of a polyvinyl alcohol hydrogel model phantom is 1.37?±?0.14?mm, with a similar performance being observed in patient experiments. PMID:26448009

  5. 2D Ultrasound and 3D MR Image Registration of the Prostate for Brachytherapy Surgical Navigation

    PubMed Central

    Zhang, Shihui; Jiang, Shan; Yang, Zhiyong; Liu, Ranlu

    2015-01-01

    Abstract Two-dimensional (2D) ultrasound (US) images are widely used in minimally invasive prostate procedure for its noninvasive nature and convenience. However, the poor quality of US image makes it difficult to be used as guiding utility. To improve the limitation, we propose a multimodality image guided navigation module that registers 2D US images with magnetic resonance imaging (MRI) based on high quality preoperative models. A 2-step spatial registration method is used to complete the procedure which combines manual alignment and rapid mutual information (MI) optimize algorithm. In addition, a 3-dimensional (3D) reconstruction model of prostate with surrounding organs is employed to combine with the registered images to conduct the navigation. Registration accuracy is measured by calculating the target registration error (TRE). The results show that the error between the US and preoperative MR images of a polyvinyl alcohol hydrogel model phantom is 1.37?±?0.14?mm, with a similar performance being observed in patient experiments. PMID:26448009

  6. 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.

  7. 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.

  8. 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-time imaging (using a 3 s data acquisition time) of different brachytherapy seed configurations (with an activity of 0.05 U) throughout a 60 Multiplication-Sign 60 Multiplication-Sign 60 mm{sup 3} Perspex prostate phantom. Conclusions: The newly developed miniature gamma camera component of BrachyView, with its high spatial resolution and real time capability, allows accurate 3D localization of seeds in a prostate phantom. Combination of the gamma camera with TRUS in a single probe will complete the BrachyView system.

  9. 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-CRT patients and 7% of IMRT patients (p = 0.046); logistic regression analysis also confirmed this observation (p = 0.040). Conclusions: When used in combination with brachytherapy, IMRT offers less Grade {>=}2 rectal bleeding, less acute urinary toxicities, and is associated with a higher QOL compared with 3D-CRT.

  10. 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 (1.8%). Conclusions: ISA causes the delivered dose in prostate seed implant brachytherapy to be lower than the dose calculated by TG-43U1. MC simulation of phantom seed arrangements show that dose at a point can be reduced by up to 18% and this has been validated using a MOSFET dosimeter. Clinical simulations show that ISA reduces DVH parameter values, but the reduction is less for thinner seeds.

  11. 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.

  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. 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.

  14. 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.

  15. Transperineal Injection of Hyaluronic Acid in Anterior Perirectal Fat to Decrease Rectal Toxicity From Radiation Delivered With Intensity Modulated Brachytherapy or EBRT for Prostate Cancer Patients

    SciTech Connect

    Prada, Pedro J. Fernandez, Jose; Martinez, Alvaro A.; Rua, Angeles de la; Gonzalez, Jose M.; Fernandez, Jose M.; Juan, German

    2007-09-01

    Purpose: Rectal toxicity remains a serious complication affecting quality of life for prostate cancer patients treated with radiotherapy. We began an investigational trial injecting hyaluronic acid (HA) in the perirectal fat to increase the distance between the prostate and the anterior rectal wall. This is the first report using HA injection in oncology. Methods and Materials: This is a trial of external beam radiation therapy with HDR brachytherapy boosts in prostate cancer. During the two high-dose-rate (HDR) fractions, thermoluminescent dosimeter dosimeters were placed in the urethra and in the rectum. Before the second HDR fraction, 3-7 mL (mean, 6 mL) of HA was injected under transrectal ultrasound guidance in the perirectal fat to systematically create a 1.5-cm space. Urethral and rectal HDR doses were calculated and measured. Computed tomography and magnetic resonance imaging were used to assess the stability of the new space. Results: Twenty-seven patients enrolled in the study. No toxicity was produced from the HA or the injection. In follow-up computed tomography and magnetic resonance imaging, the HA injection did not migrate or change in mass/shape for close to 1 year. The mean distance between rectum and prostate was 2.0 cm along the entire length of the prostate. The median measured rectal dose, when normalized to the median urethral dose, demonstrated a decrease in dose from 47.1% to 39.2% (p < 0.001) with or without injection. For an HDR boost dose of 1150 cGy, the rectum mean Dmax reduction was from 708 cGy to 507 cGy, p < 0.001, and the rectum mean Dmean drop was from 608 to 442 cGy, p < 0.001 post-HA injection. Conclusion: The new 2-cm distance derived from the HA injection significantly decreased rectal dose in HDR brachytherapy. Because of the several-month duration of stability, the same distance was maintained during the course of external beam radiation therapy.

  16. 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 Grade 2 rectal bleeding.

  17. 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.

  18. 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.

  19. 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 to 10% of the urethra cutpoint for urinary health-related quality of life was 120% of the prescription dose. Conclusion: EPIC was a more sensitive tool for detecting the effects on function and bother than were the generic toxicity scales. The urethral dose had the strongest association with a deteriorating urinary quality of life.

  20. Anatomy-Based Inverse Planning Simulated Annealing Optimization in High-Dose-Rate Prostate Brachytherapy: Significant Dosimetric Advantage Over Other Optimization Techniques

    SciTech Connect

    Jacob, Dayee Raben, Adam; Sarkar, Abhirup; Grimm, Jimm; Simpson, Larry

    2008-11-01

    Purpose: To perform an independent validation of an anatomy-based inverse planning simulated annealing (IPSA) algorithm in obtaining superior target coverage and reducing the dose to the organs at risk. Method and Materials: In a recent prostate high-dose-rate brachytherapy protocol study by the Radiation Therapy Oncology Group (0321), our institution treated 20 patients between June 1, 2005 and November 30, 2006. These patients had received a high-dose-rate boost dose of 19 Gy to the prostate, in addition to an external beam radiotherapy dose of 45 Gy with intensity-modulated radiotherapy. Three-dimensional dosimetry was obtained for the following optimization schemes in the Plato Brachytherapy Planning System, version 14.3.2, using the same dose constraints for all the patients treated during this period: anatomy-based IPSA optimization, geometric optimization, and dose point optimization. Dose-volume histograms were generated for the planning target volume and organs at risk for each optimization method, from which the volume receiving at least 75% of the dose (V{sub 75%}) for the rectum and bladder, volume receiving at least 125% of the dose (V{sub 125%}) for the urethra, and total volume receiving the reference dose (V{sub 100%}) and volume receiving 150% of the dose (V{sub 150%}) for the planning target volume were determined. The dose homogeneity index and conformal index for the planning target volume for each optimization technique were compared. Results: Despite suboptimal needle position in some implants, the IPSA algorithm was able to comply with the tight Radiation Therapy Oncology Group dose constraints for 90% of the patients in this study. In contrast, the compliance was only 30% for dose point optimization and only 5% for geometric optimization. Conclusions: Anatomy-based IPSA optimization proved to be the superior technique and also the fastest for reducing the dose to the organs at risk without compromising the target coverage.

  1. 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.

  2. Clinical efficacy of computed tomography-guided iodine-125 seed implantation therapy in patients with advanced spinal metastatic tumors

    PubMed Central

    Zhang, Liyun; Lu, Jian; Wang, Zhongmin; Cheng, Yingsheng; Teng, Gaojun; Chen, Kemin

    2016-01-01

    Objective The purpose of this study was to examine the safety and clinical efficacy of computed tomography (CT)-guided radioactive iodine-125 (125I) seed implantation treatment in patients with spinal metastatic tumors. Methods We retrospectively analyzed 20 cases of spinal metastatic tumors, including nine men and eleven women aged 50–79 years (mean age: 61.1 years). We used treatment planning system (TPS) to construct three-dimensional images of the spinal metastatic tumors and to determine what number and dose rate distribution to use for the 125I seeds. The matched peripheral dose of the 125I seed implantation was 90–130 Gy. Twenty-four spinal metastatic tumors were treated by CT-guided radioactive 125I seed implantation. A median of 19 (range: 4–43) 125I seeds were implanted. Results Twenty cases were followed for a median of 15.3 months (range: 7–32 months). The rate of pain relief was 95%. The median control time for all of the patients was 12.5 months. The 3-, 6-, and 12-month cumulative local control rates were 100%, 95%, and 60%, respectively. The median survival time for all of the patients was 16 months. The cumulative 6- and 12-month survival rates were 100% and 78.81%, respectively. No major complications were observed. No 125I seeds were lost or migrated to other tissues or organs. Conclusion CT-guided radioactive 125I seed implantation is a safe, effective, and minimally invasive method for the treatment of patients with spinal metastatic tumors. It is a possible alternative therapy for the treatment of spinal metastases. PMID:26719712

  3. 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.

  4. Prostate brachytherapy - discharge

    MedlinePLUS

    ... rest to help speed your recovery. Avoid heavy activity (such as housework, yard work, and lifting children) for at least 1 week. You should be able to return to your normal activities after that. You can resume sexual activity when ...

  5. ROPES eye plaque dosimetry: commissioning and verification of an ophthalmic brachytherapy treatment planning system

    NASA Astrophysics Data System (ADS)

    Poder, J.; Annabell, N.; Geso, M.; Alqathami, M.; Corde, S.

    2013-06-01

    In this study, the Plaque SimulatorTM eye plaque brachytherapy planning system was commissioned for ROPES eye plaques and Amersham Health model 6711 Iodine 125 seeds, using TG43-UI data. The brachytherapy module of the RADCALC® independent checking program was configured to allow verification of the accuracy of the dose calculated by Plaque SimulatorTM. Central axis depth dose distributions were compared and observed to agree to within 2% for all ROPES plaque models and depths of interest. Experimental measurements were performed with a customized PRESAGEm 3-D type dosimeter to validate the calculated depth dose distributions. Preliminary results have shown the effect of the stainless steel plaque backing decreases the measured fluorescence intensity by up to 25%, and 40% for the 15 mm and 10 mm diameter ROPES plaques respectively. This effect, once fully quantified should be accounted for in the Plaque SimulatorTM eye plaque brachytherapy planning system.

  6. 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 delivery, free of most potential human related errors identified in ICRP 97. This research is supported by funding from the Australian Government Department of Health through Cancer Australia grant no. 616614.

  7. 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.

  8. 4D analysis of influence of patient movement and anatomy alteration on the quality of 3D U/S-based prostate HDR brachytherapy treatment delivery

    SciTech Connect

    Milickovic, Natasa; Mavroidis, Panayiotis; Tselis, Nikolaos; Nikolova, Iliyana; Katsilieri, Zaira; Kefala, Vasiliki; Zamboglou, Nikolaos; Baltas, Dimos

    2011-09-15

    Purpose: Modern HDR brachytherapy treatment for prostate cancer based on the 3D ultrasound (U/S) plays increasingly important role. The purpose of this study is to investigate possible patient movement and anatomy alteration between the clinical image set acquisition, made after the needle implantation, and the patient irradiation and their influence on the quality of treatment. Methods: The authors used 3D U/S image sets and the corresponding treatment plans based on a 4D-treatment planning procedure: plans of 25 patients are obtained right after the needle implantation (clinical plan is based on this 3D image set) and just before and after the treatment delivery. The authors notice the slight decrease of treatment quality with increase of time gap between the clinical image set acquisition and the patient irradiation. 4D analysis of dose-volume-histograms (DVHs) for prostate: CTV1 = PTV, and urethra, rectum, and bladder as organs at risk (OARs) and conformity index (COIN) is presented, demonstrating the effect of prostate, OARs, and needles displacement. Results: The authors show that in the case that the patient body movement/anatomy alteration takes place, this results in modification of DVHs and radiobiological parameters, hence the plan quality. The observed average displacement of needles (1 mm) and of prostate (0.57 mm) is quite small as compared with the average displacement noted in several other reports [A. A. Martinez et al., Int. J. Radiat. Oncol., Biol., Phys. 49(1), 61-69 (2001); S. J. Damore et al., Int. J. Radiat. Oncol., Biol., Phys. 46(5), 1205-1211 (2000); P. J. Hoskin et al., Radiotherm. Oncol. 68(3), 285-288 (2003); E. Mullokandov et al., Int. J. Radiat. Oncol., Biol., Phys. 58(4), 1063-1071 (2004)] in the literature. Conclusions: Although the decrease of quality of dosimetric and radiobiological parameters occurs, this does not cause clinically unacceptable changes to the 3D dose distribution, according to our clinical protocol.

  9. 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.

  10. 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.

  11. 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.

  12. Prostate cancer - treatment

    MedlinePLUS

    ... for more advanced cancers. Brachytherapy involves placing radioactive seeds inside the prostate gland. A surgeon inserts small ... the skin beneath your scrotum to inject the seeds. The seeds are so small that you do ...

  13. Burden of focal cryoablation versus brachytherapy versus active surveillance in the treatment of very low-risk prostate cancer: a preliminary head-to-head comprehensive assessment.

    PubMed

    de Cerqueira, M A; Laranja, W W; Sanches, B C F; Monti, C R; Reis, L O

    2015-11-01

    Focal cryoablation (FC), brachytherapy (B) and active surveillance (AS) were offered to patients diagnosed with very low-risk prostate cancer (VLRPC) in an equal access protocol. Comprehensive validated self-report questionnaires accessed patients' erectile (IIEF-5) and voiding (IPSS) functions, Beck scales measured anxiety (BAI), hopelessness (BHS) and depression (BDI), SF-36 reflected patients' quality of life added to the emotional thermometers including five visual analogue scales (distress, anxiety, depression, anger and need for help). Kruskal-Wallis or ANOVA tests and Spearman's correlations were obtained among groups and studied variables. Thirty patients were included, median follow-up 18 months (15-21). Those on AS (n = 11) were older, presented higher hopelessness (BHS) and lower general health perceptions (SF-36) scores than patients opting for FC (n = 10) and B (n = 9), P = 0.0014, P = 0.0268 and P = 0.0168 respectively. Patients on B had higher IPSS scores compared to those under FC and AC, P = 0.0223. For all 30 included patients, Spearman's correlation (rs ) was very strong between BHS and general health perceptions (rs  = -0.800, P < 0.0001), and weak/moderate between age and BHS (rs  = 0.405, P = 0.026) and age and general health perceptions (rs  = -0.564, P = 0.001). The sample power was >60%. To be considered in patients' counselling and care, current study supports the hypothesis that even VLRPC when untreated undermines psychosocial domains. PMID:25752993

  14. 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.

  15. 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.

  16. Equivalent Biochemical Control and Improved Prostate-Specific Antigen Nadir After Permanent Prostate Seed Implant Brachytherapy Versus High-Dose Three-Dimensional Conformal Radiotherapy and High-Dose Conformal Proton Beam Radiotherapy Boost

    SciTech Connect

    Jabbari, Siavash; Weinberg, Vivian K.; Shinohara, Katsuto; Speight, Joycelyn L.; Gottschalk, Alexander R.; Hsu, I.-C.; Pickett, Barby; McLaughlin, Patrick W.; Sandler, Howard M.; Roach, Mack

    2010-01-15

    Purpose: Permanent prostate implant brachytherapy (PPI), three-dimensional conformal radiotherapy (3D-CRT), and conformal proton beam radiotherapy (CPBRT) are used in the treatment of localized prostate cancer, although no head-to-head trials have compared these modalities. We studied the biochemical control (biochemical no evidence of disease [bNED]) and prostate-specific antigen (PSA) nadir achieved with contemporary PPI, and evaluated it against 3D-CRT and CPBRT. Patients and Methods: A total of 249 patients were treated with PPI at the University of California, San Francisco, and the outcomes were compared with those from a 3D-CRT cohort and the published results of a high-dose CPBRT boost (CPBRTB) trial. For each comparison, subsets of the PPI cohort were selected with patient and disease criteria similar to those of the reference group. Results: With a median follow-up of 5.3 years, the bNED rate at 5 and 7 years achieved with PPI was 92% and 86%, respectively, using the American Society for Therapeutic Radiology and Oncology (ASTRO) definition, and 93% using the PSA nadir plus 2 ng/mL definition. Using the ASTRO definition, a 5-year bNED rate of 78% was achieved for the 3D-CRT patients compared with 94% for a comparable PPI subset and 93% vs. 92%, respectively, using the PSA nadir plus 2 ng/mL definition. The median PSA nadir for patients treated with PPI and 3D-CRT was 0.10 and 0.40 ng/mL, respectively (p < .0001). For the CPBRT comparison, the 5-year bNED rate after a CPBRTB was 91% using the ASTRO definition vs. 93% for a similar group of PPI patients. A greater proportion of PPI patients achieved a lower PSA nadir compared with those achieved in the CPBRTB trial (PSA nadir <=0.5 ng/mL, 91% vs. 59%, respectively). Conclusion: We have demonstrated excellent outcomes in low- to intermediate-risk patients treated with PPI, suggesting at least equivalent 5-year bNED rates and a greater proportion of men achieving lower PSA nadirs compared with 3D-CRT or CPBRTB.

  17. Direct 2-Arm Comparison Shows Benefit of High-Dose-Rate Brachytherapy Boost vs External Beam Radiation Therapy Alone for Prostate Cancer

    SciTech Connect

    Khor, Richard; Duchesne, Gillian; Monash University, Melbourne ; Tai, Keen-Hun; Foroudi, Farshad; Chander, Sarat; Van Dyk, Sylvia; Garth, Margaret; Williams, Scott

    2013-03-01

    Purpose: To evaluate the outcomes of patients treated for intermediate- and high-risk prostate cancer with a single schedule of either external beam radiation therapy (EBRT) and high-dose-rate brachytherapy (HDRB) boost or EBRT alone. Methods and Materials: From 2001-2006, 344 patients received EBRT with HDRB boost for definitive treatment of intermediate- or high-risk prostate cancer. The prescribed EBRT dose was 46 Gy in 23 fractions, with a HDR boost of 19.5 Gy in 3 fractions. This cohort was compared to a contemporaneously treated cohort who received EBRT to 74 Gy in 37 fractions, using a matched pair analysis. Three-dimensional conformal EBRT was used. Matching was performed using a propensity score matching technique. High-risk patients constituted 41% of the matched cohorts. Five-year clinical and biochemical outcomes were analyzed. Results: Initial significant differences in prognostic indicators between the unmatched treatment cohorts were rendered negligible after matching, providing a total of 688 patients. Median biochemical follow-up was 60.5 months. The 5-year freedom from biochemical failure was 79.8% (95% confidence interval [CI], 74.3%-85.0%) and 70.9% (95% CI, 65.4%-76.0%) for the HDRB and EBRT groups, respectively, equating to a hazard ratio of 0.59 (95% CI, 0.43-0.81, P=.0011). Interaction analyses showed no alteration in HDR efficacy when planned androgen deprivation therapy was administered (P=.95), but a strong trend toward reduced efficacy was shown compared to EBRT in high-risk cases (P=.06). Rates of grade 3 urethral stricture were 0.3% (95% CI, 0%-0.9%) and 11.8% (95% CI, 8.1%-16.5%) for EBRT and HDRB, respectively (P<.0001). No differences in clinical outcomes were observed. Conclusions: This comparison of 2 individual contemporaneously treated HDRB and EBRT approaches showed improved freedom from biochemical progression with the HDR approach. The benefit was more pronounced in intermediate- risk patients but needs to be weighed against an increased risk of urethral toxicity.

  18. 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-risk prostate cancer patients treated with a single implant HDR-BT to 24-27 Gy in two fractions within 1 day have excellent tolerance with minimal acute and chronic toxicity. Longer follow-up is needed to confirm these encouraging early results.

  19. 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

  20. 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.

  1. 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.

  2. MIP Models and BB Strategies in Brachytherapy Treatment Optimization

    E-print Network

    Meyer, Robert R.

    of therapy is becoming com­ mon in the treatment of early stage prostate cancer, the most common cancer: brachytherapy, prostate cancer, branch­and­bound, optimization, inte­ ger programming, treatment planning in the Netherlands. t.tex; 31/05/2001; 16:31; p.1 #12; 2 1. Introduction Prostate cancer is the most common cancer

  3. 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

  4. 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 low toxicity and encouraging early indicators of disease control.

  5. 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 tumor cure probability models, are reviewed. Based on these developments in literature, the AAPM recommends guidelines for dose prescription from a physics perspective for routine patient treatment, clinical trials, and for treatment planning software developers. The authors continue to follow the current recommendations on using D{sub 90} and V{sub 100} as the primary quantities, with more specific guidelines on the use of the imaging modalities and the timing of the imaging. The AAPM recommends that the postimplant evaluation should be performed at the optimum time for specific radionuclides. In addition, they encourage the use of a radiobiological model with a specific set of parameters to facilitate relative comparisons of treatment plans reported by different institutions using different loading patterns or radionuclides.

  6. 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.

  7. Prostate-specific antigen (Pasa) bounce and other fluctuations: Which biochemical relapse definition is least prone to PSA false calls? An analysis of 2030 men treated for prostate cancer with external beam or brachytherapy with or without adjuvant androgen deprivation therapy

    SciTech Connect

    Pickles, Tom . E-mail: tpickles@bccancer.bc.ca

    2006-04-01

    Purpose: To determine the false call (FC) rate for prostate-specific antigen (PSA) relapse according to nine different PSA relapse definitions after a PSA fluctuation (bounce) has occurred after external beam radiation therapy (EBRT) or brachytherapy, with or without adjuvant androgen deprivation therapy. Methods and Materials: An analysis of a prospective database of 2030 patients was conducted. Prostate-specific antigen relapse was scored according to the American Society for Therapeutic Radiology and Oncology (ASTRO), Vancouver, threshold + n, and nadir + n definitions for the complete data set and then compared against a truncated data set, with data subsequent to the height of the bounce deleted. The FC rate was calculated for each definition. Results: The bounce rate, with this very liberal definition of bounce, was 58% with EBRT and 84% with brachytherapy. The FC rate was lowest with nadir + 2 and + 3 definitions (2.2% and 1.6%, respectively) and greatest with low-threshold and ASTRO definitions (32% and 18%, respectively). The ASTRO definition was particularly susceptible to FC when androgen deprivation therapy was used with radiation (24%). Discussion: New definitions of biochemical non-evidence of disease that are more robust than the ASTRO definition have been identified. Those with the least FC rates are the nadir + 2 and nadir + 3 definitions, both of which are being considered to replace the ASTRO definition by the 2005 meeting of the Radiation Therapy Oncology Group-ASTRO consensus panel.

  8. 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.

  9. 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.

  10. 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. PMID:25820802

  11. 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.

  12. 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.

  13. Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy

    NASA Astrophysics Data System (ADS)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-10-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, 169Yb and 103Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for 103Pd, 125I, 131Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

  14. Automated Finite Element Analysis for Deformable Registration of Prostate Images

    E-print Network

    Crouch, Jessica R.

    of radiotherapy treatment for prostate cancer. Both external beam radiation and brachytherapy require regis1 Automated Finite Element Analysis for Deformable Registration of Prostate Images Jessica R and deformation due to swelling. Index Terms-- registration, elastic, finite element, m-rep, prostate I

  15. Medially Based Meshing with Finite Element Analysis of Prostate Deformation

    E-print Network

    Crouch, Jessica R.

    and guidance. Brachytherapy involves implanting radioactive seeds in the prostate to treat prostate cancerMedially Based Meshing with Finite Element Analysis of Prostate Deformation Jessica R. Crouch1, University of North Carolina at Chapel Hill 2 Memorial Sloan-Kettering Cancer Center Abstract. The finite

  16. 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 were clearly superior in terms of BW, RW, and normal tissue sparing, with lowest values for HDR-BT.

  17. 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. PMID:25620161

  18. 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% [?: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 refinement of this recommendation.

  19. Advanced brachytherapy dosimetric considerations

    E-print Network

    Melhus, Christopher S. (Christopher Scott), 1974-

    2008-01-01

    The practice of brachytherapy and brachytherapy dosimetry was investigated with emphasis on evaluations of dose distributions and shielding considerations for both photon- and neutron-emitting radionuclides. Monte Carlo ...

  20. 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-induced lower urinary tract symptoms than the other two agents.

  1. 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.

  2. 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.

  3. Robot-guided open-loop insertion of skew-line needle arrangements for high dose rate brachytherapy

    E-print Network

    2013-01-01

    Robotic system for prostate brachytherapy,” Computer Aided Surgery,robotic system for mri-guided prostate needle placement,” The International Journal of Medical Robotics and Computer Assisted Surgery,robotic fd-ct-guided navigation system for needle placementpreliminary accuracy tests,” The Interna- tional Journal of Medical Robotics and Computer Assisted Surgery,

  4. Prostate Adenocarcinoma

    Cancer.gov

    Home Cancers Selected for Study Prostate Adenocarcinoma Prostate Adenocarcinoma Last Updated: November 05, 2015 What is prostate cancer? Prostate cancer is a disease of the prostate, a walnut-size gland in the male reproductive system.  Nearly all

  5. Prostate Diseases

    MedlinePLUS

    Aging & Health A to Z Prostate Diseases Basic Facts & Information What are Prostate Diseases? The prostate—one of the components of a man's sex organs—is a ... out anything serious. The Most Common Types of Prostate Diseases Benign prostatic hyperplasia (BPH) Prostatitis Prostate cancer ...

  6. [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

  7. 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.

  8. Prostate Problems

    MedlinePLUS

    ... a combination of medicines, surgery, and lifestyle changes. Prostate Cancer Prostate cancer is common among American men. Your ... fruits and vegetables may raise your risk. Diagnosing Prostate Cancer At the start, prostate cancer does not cause ...

  9. 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 ... not cancerous, or malignant, which means cancerous. How Prostate Cancer Occurs Prostate cancer occurs when a tumor forms ...

  10. Treatment- and Disease-Related Complications of Prostate Cancer

    PubMed Central

    Simoneau, Anne R

    2006-01-01

    One of the highlights of the 16th International Prostate Cancer Update was a session on treatment- and disease-related complications of prostate disease. It began with presentation of a challenging case of rising prostate-specific antigen levels after radical prostatectomy, followed by an overview of the use of zoledronic acid in prostate cancer, a review of side effects of complementary medicines, an overview of complications of cryotherapy, an assessment of complications of brachytherapy and external beam radiation therapy, and a comparison of laparoscopy versus open prostatectomy. PMID:17021643

  11. 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

  12. Prostate cancer

    MedlinePLUS

    ... will also be used to monitor your cancer after treatment. ... the prostate gland, common treatments include: Surgery ( radical ... or after other treatments. If prostate cancer spreads even after ...

  13. Prostatitis: Disorders of the Prostate

    MedlinePLUS

    ... shaped gland that is part of the male reproductive system. The main function of the prostate is to ... shaped gland that is part of the male reproductive system. [ Top ] What causes prostatitis? The causes of prostatitis ...

  14. 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

  15. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications.

    PubMed

    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 (125)I 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. PMID:26061230

  16. 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.

  17. 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.

  18. [Salvage cryotherapy for recurrent prostate cancer after radiotherapy failure: principles, indications, patient selection, oncological results and morbidity].

    PubMed

    Hétet, J-F; Colls, P; Pocholle, P; Chauveau, P; Barré, C; Hallouin, P

    2014-11-01

    Potentially curative salvage options for biochemical failure after primary prostatic radiotherapy include salvage radical prostatectomy, brachytherapy, high-intensity focused ultrasound and cryotherapy. Salvage cryoablation for recurrent prostate cancer after irradiation failure is currently a well-established therapeutic option, since technical improvements have permitted better oncologic outcomes and lower complications rates over the years. This article reviews surgical technique, oncologic and functional outcomes, as well as morbidity and complications of salvage cryotherapy for local recurrence after external beam radiotherapy or brachytherapy for prostate cancer. PMID:24910288

  19. High-dose-rate brachytherapy combined with hypofractionated external beam radiotherapy for men with intermediate or high risk prostate cancer: analysis of short- and medium-term urinary toxicity and biochemical control

    PubMed Central

    Pellizzon, Antonio Cassio Assis; Fogaroli, Ricardo Cesar; Silva, Maria Leticia Gobo; Castro, Douglas Guedes; Maia, Maria Conte; Lopes, Ademar

    2011-01-01

    The best management of localized and locally advanced prostate cancer remains controversial, but there are clinical evidences that for patients considered of unfavorable outcome that dose escalation radiotherapy has a significantly better outcome. Methods: Between 2005-2009 a total of 39 unfavorable patients were treated in a phase I-II trial for dose escalation with high-dose rate (HDR)- 30 Gy given by 4 fractions BID, in two separated implants and hypofractionated conformal/tri-dimensional radiotherapy (hEBRT) - 45 Gy (3 Gy per fraction in 3 weeks), at Hospital AC Camargo, Sao Paulo, Brazil. Results: Median age of patients was 69 (range, 58-80) years old. With a median follow up of 42.5 months the highest RTOG acute severe genitourinary toxicity (GU-TX) was grade 3 in two (5.1%) patients. Late severe GU-TX was observed in one (2.6%) patient. On univariate analysis the prostate volume > 45cc (p=0.024), <11 needles per implant (p=0.038) and urethral dose >130% of prescribed dose (p<0,001) were statistical significant predictive factors. Multivariate analysis showed urethral dose >130% as the only predictive factor for late severe GU-TX, p=0.017 (95%CI-1.39-29.49), HR-6.4. The actuarial overall survival, biochemical control and disease specific survival rates for the entire group at 3.5-years were 92.0%, 87.6% and 96.9%, respectively. Conclusion: HDR combined to hEBRT is well tolerated in the short and medium term. Acute toxicity was minimal and improved outcomes in terms of reduced late toxicity can be achieved using at least 11 needles and prostate with no more than 45cc to be implanted. The maximum urethral dose should be kept bellow 130% of prescribed dose. PMID:21394285

  20. IPIP: A New Approach to Inverse Planning for HDR Brachytherapy by Directly Optimizing Dosimetric Indices

    E-print Network

    Siauw, Timmy; Atamturk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2010-01-01

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy treatment planning 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 improve HDR brachytherapy planning by developing a new approach that directly optimizes the dose distribution based on dosimetric criteria. Method: We develop Inverse Planning by Integer Program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. We used our heuristic to compute dose plans for 20 anonymized prostate cancer patient image data sets from our clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Results: Dose plans computed from IPIP satis?ed al...

  1. Treatment of Localized Prostate Cancer

    PubMed Central

    Akduman, Bulent; Crawford, E. David

    2006-01-01

    This article provides an overview of treatment of localized prostate cancer, which was discussed in detail in the second scientific session of the 16th International Prostate Cancer Update. The role of radical prostatectomy in localized disease was presented by Bob Djavan, MD. Benefits and risks of radical prostatectomy were addressed by Gerald Chodak, MD. Robert E. Donohue, MD, presented the role of radical prostatectomy in Gleason grade 8, 9, and 10 tumors. Impact of positive margins on outcomes after radical prostatectomy was presented by James A. Eastham, MD. E. David Crawford, MD, provided an overview of the role of targeted therapy. Indications and results of brachytherapy were presented by Mack Roach, III, MD. Finally, Michael J. Manyak, MD, described the evolution of radioimmunoscintigraphy and clinical outcomes data. PMID:17021637

  2. Dosimetric equivalence of non-standard high dose rate (HDR) brachytherapy catheter patterns

    E-print Network

    Cunha, J Adam M; Pouliot, Jean

    2009-01-01

    Purpose: To determine whether alternative HDR prostate brachytherapy catheter patterns can result in improved dose distributions while providing better access and reducing trauma. Methods: Prostate HDR brachytherapy uses a 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. On CT data from ten previously-treated patients new catheters were digitized following three 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 p...

  3. 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 ...

  4. 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.

  5. 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 ...

  6. 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 catheter insertion. In addition, alternative catheter patterns may decrease toxicity by avoidance of the critical structures near the penile bulb while still fulfilling the RTOG criteria.

  7. Optimal drug release schedule for in-situ radiosensitization of image guided permanent prostate implants

    E-print Network

    Sridhar, Srinivas

    Optimal drug release schedule for in-situ radiosensitization of image guided permanent prostate will have a limited drug-loading capacity, and the drug release schedule that optimizes outcome, under. The interaction between brachytherapy dose distributions and drug distribution around drug eluting spacers

  8. 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.

  9. Prediction of Erectile Function Following Treatment for Prostate Cancer

    PubMed Central

    Alemozaffar, Mehrdad; Regan, Meredith M.; Cooperberg, Matthew R.; Wei, John T.; Michalski, Jeff M.; Sandler, Howard M.; Hembroff, Larry; Sadetsky, Natalia; Saigal, Christopher S.; Litwin, Mark S.; Klein, Eric; Kibel, Adam S.; Hamstra, Daniel A.; Pisters, Louis L.; Kuban, Deborah A.; Kaplan, Irving D.; Wood, David P.; Ciezki, Jay; Dunn, Rodney L.; Carroll, Peter R.; Sanda, Martin G.

    2013-01-01

    Context Sexual function is the health-related quality of life (HRQOL) domain most commonly impaired after prostate cancer treatment; however, validated tools to enable personalized prediction of erectile dysfunction after prostate cancer treatment are lacking. Objective To predict long-term erectile function following prostate cancer treatment based on individual patient and treatment characteristics. Design Pretreatment patient characteristics, sexual HRQOL, and treatment details measured in a longitudinal academic multicenter cohort (Prostate Cancer Outcomes and Satisfaction With Treatment Quality Assessment; enrolled from 2003 through 2006), were used to develop models predicting erectile function 2 years after treatment. A community-based cohort (community-based Cancer of the Prostate Strategic Urologic Research Endeavor [CaPSURE]; enrolled 1995 through 2007) externally validated model performance. Patients in US academic and community-based practices whose HRQOL was measured pretreatment (N = 1201) underwent follow-up after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer. Sexual outcomes among men completing 2 years’ follow-up (n = 1027) were used to develop models predicting erectile function that were externally validated among 1913 patients in a community-based cohort. Main Outcome Measures Patient-reported functional erections suitable for intercourse 2 years following prostate cancer treatment. Results Two years after prostate cancer treatment, 368 (37% [95% CI, 34%–40%]) of all patients and 335 (48% [95% CI, 45%–52%]) of those with functional erections prior to treatment reported functional erections; 531 (53% [95% CI, 50%–56%]) of patients without penile prostheses reported use of medications or other devices for erectile dysfunction. Pretreatment sexual HRQOL score, age, serum prostate-specific antigen level, race/ethnicity, body mass index, and intended treatment details were associated with functional erections 2 years after treatment. Multivariable logistic regression models predicting erectile function estimated 2-year function probabilities from as low as 10% or less to as high as 70% or greater depending on the individual’s pretreatment patient characteristics and treatment details. The models performed well in predicting erections in external validation among CaPSURE cohort patients (areas under the receiver operating characteristic curve, 0.77 [95% CI, 0.74–0.80] for prostatectomy; 0.87 [95% CI, 0.80–0.94] for external radiotherapy; and 0.90 [95% CI, 0.85–0.95] for brachytherapy). Conclusion Stratification by pretreatment patient characteristics and treatment details enables prediction of erectile function 2 years after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer. PMID:21934053

  10. The Prostate Normaland Prostate Cancer Cells Display

    E-print Network

    Tong, Liang

    The Prostate Normaland Prostate Cancer Cells Display Distinct Molecular Profiles of a epithelial cells (PZ-HPV-7), androgen-dependent prostate cancer cells (LNCaP), transitional androgen-independent prostate cancer cells (LNCaP-cds and CWR22Rv1), and androgen- independent prostate cancer cells (PC3

  11. What is Prostate Cancer?

    MedlinePLUS

    ... the key statistics about prostate cancer? What is prostate cancer? To understand prostate cancer, it helps to know ... cancer ” section for a description of this procedure.) Prostate cancer Several types of cells are found in the ...

  12. Prostate Cancer Prevention

    MedlinePLUS

    ... prostate. The prostate is a gland in the male reproductive system . The prostate is just below the bladder (the ... part of the semen . Enlarge Anatomy of the male reproductive and urinary systems, showing the prostate, testicles, bladder, and other organs. ...

  13. [Prostate cancer 2010. Therapeutic innovations].

    PubMed

    Richaud, P; Chapet, O; Azria, D; Soulié, M; Salomon, L; Hennequin, C; Culine, S

    2011-03-01

    During the annual congress of the SFRO, a symposium, on "Therapeutic innovations", described some of the burning questions in the treatment of prostate cancer. What is the best technique to perform radiation dose escalation, brachytherapy or Intensity modulated radiotherapy? Rational has been highlighted for both techniques, but without a prospective comparative trial, no definitive answer could be given today. The role of neo-adjuvant hormonal treatment, before surgery or radiotherapy is still discussed, particularly in the area of LH-RH antagonists which have a rapid and profound anti-hormonal effect. At least, the salvage treatment for biochemical relapse after external beam irradiation has been discussed: surgery, cryotherapy, and High-Intensity focalised ultrasons and the timing of hormonal treatment. PMID:21513892

  14. 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.

  15. 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.

  16. Current state of prostate cancer treatment in Jamaica.

    PubMed

    Morrison, Belinda F; Aiken, William D; Mayhew, Richard

    2014-01-01

    Prostate cancer is the commonest cancer in Jamaica as well as the leading cause of cancer-related deaths. One report suggested that Jamaica has the highest incidence rate of prostate cancer in the world, with an age-standardised rate of 304/100,000 per year. The Caribbean region is reported to have the highest mortality rate of prostate cancer worldwide. Prostate cancer accounts for a large portion of the clinical practice for health-care practitioners in Jamaica. The Jamaica Urological Society is a professional body comprising 19 urologists in Jamaica who provide most of the care for men with prostate cancer in collaboration with medical oncologists, radiation oncologists, and a palliative care physician. The health-care system is structured in two tiers in Jamaica: public and private. The urologist-to-patient ratio is high, and this limits adequate urological care. Screening for prostate cancer is not a national policy in Jamaica. However, the Jamaica Urological Society and the Jamaica Cancer Society work synergistically to promote screening as well as to provide patient education for prostate cancer. Adequate treatment for localised prostate cancer is available in Jamaica in the forms of active surveillance, nerve-sparing radical retropubic prostatectomy, external beam radiation, and brachytherapy. However, there is a geographic maldistribution of centres that provide prostate cancer treatment, which leads to treatment delays. Also, there is difficulty in affording some treatment options in the private health-care sectors. Androgen deprivation therapy is available for treatment of locally advanced and metastatic prostate cancer and is subsidised through a programme called the National Health Fund. Second-line hormonal agents and chemotherapeutic agents are available but are costly to most of the population. The infrastructure for treatment of prostate cancer in Jamaica is good, but it requires additional technological advances as well as additional specialist services. PMID:25228912

  17. Image-based brachytherapy for cervical cancer

    PubMed Central

    Vargo, John A; Beriwal, Sushil

    2014-01-01

    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 cancer) trial, along with continued improvements in imaging, contouring, quality assurance, physics, and brachytherapy delivery promise to perpetuate the advancement of image-based brachytherapy to optimize outcomes for cervical cancer patients. PMID:25493230

  18. Benign prostate hyperplasia (BPH) - resources

    MedlinePLUS

    Resources - benign prostatic hyperplasia (BPH); Prostate enlargement resources; BPH resources ... organizations provide information on benign prostatic hyperplasia ( prostate enlargement ): National Kidney and Urologic Diseases Information Clearinghouse -- www. ...

  19. Prostate Problems

    MedlinePLUS

    ... a blood test to check the prostatespecific antigen (PSA) level. PSA levels can be high in men with an ... visit their website at www.cancer.gov/prostate . PSA Testing Some doctors think that men younger than ...

  20. 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.

  1. 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.

  2. Prostatitis (Infection of the Prostate)

    MedlinePLUS

    ... conditions can happen in men of all ages. Male Reproductive System Medical Illustration Copyright © 2015 Nucleus Medical Media, All ... walnut-shaped gland that is part of the male reproductive system. The prostate sits under the bladder and in ...

  3. 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.

  4. EM-Navigated Catheter Placement for Gynecologic Brachytherapy: An Accuracy Study.

    PubMed

    Mehrtash, Alireza; Damato, Antonio; Pernelle, Guillaume; Barber, Lauren; Farhat, Nabgha; Viswanathan, Akila; Cormack, Robert; Kapur, Tina

    2014-03-12

    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

  5. 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

  6. 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.

  7. 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.

  8. Cost Implications of the Rapid Adoption of Newer Technologies for Treating Prostate Cancer

    PubMed Central

    Nguyen, Paul L.; Gu, Xiangmei; Lipsitz, Stuart R.; Choueiri, Toni K.; Choi, Wesley W.; Lei, Yin; Hoffman, Karen E.; Hu, Jim C.

    2011-01-01

    Purpose Intensity-modulated radiation therapy (IMRT) and laparoscopic or robotic minimally invasive radical prostatectomy (MIRP) are costlier alternatives to three-dimensional conformal radiation therapy (3D-CRT) and open radical prostatectomy for treating prostate cancer. We assessed temporal trends in their utilization and their impact on national health care spending. Methods Using Surveillance, Epidemiology, and End Results–Medicare linked data, we determined treatment patterns for 45,636 men age ? 65 years who received definitive surgery or radiation for localized prostate cancer diagnosed from 2002 to 2005. Costs attributable to prostate cancer care were the difference in Medicare payments in the year after versus the year before diagnosis. Results Patients received surgery (26%), external RT (38%), or brachytherapy with or without RT (36%). Among surgical patients, MIRP utilization increased substantially (1.5% among 2002 diagnoses v 28.7% among 2005 diagnoses, P < .001). For RT, IMRT utilization increased substantially (28.7% v 81.7%; P < .001) and for men receiving brachytherapy, supplemental IMRT increased significantly (8.5% v 31.1%; P < .001). The mean incremental cost of IMRT versus 3D-CRT was $10,986 (in 2008 dollars); of brachytherapy plus IMRT versus brachytherapy plus 3D-CRT was $10,789; of MIRP versus open RP was $293. Extrapolating these figures to the total US population results in excess spending of $282 million for IMRT, $59 million for brachytherapy plus IMRT, and $4 million for MIRP, compared to less costly alternatives for men diagnosed in 2005. Conclusion Costlier prostate cancer therapies were rapidly and widely adopted, resulting in additional national spending of more than $350 million among men diagnosed in 2005 and suggesting the need for comparative effectiveness research to weigh their costs against their benefits. PMID:21402604

  9. Study of Dosimetric and Thermal Properties of a Newly Developed Thermo-brachytherapy Seed for Treatment of Solid Tumors

    NASA Astrophysics Data System (ADS)

    Gautam, Bhoj R.

    Studies on the curative effects of hyperthermia and radiation therapy on treatment of cancer show strong evidence of synergistic enhancement when both radiation and hyperthermia treatment modalities are applied simultaneously. A variety of tissue heating approaches developed to date still fail to overcome essential limitations such as inadequate temperature control, temperature non-uniformity, and prolonged time delay between hyperthermia and radiation treatments. We propose a new self-regulating Thermo-brachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent administration of brachytherapy and hyperthermia. The proposed seed is based on the BestRTM Iodine-125 seed model 2301, where the tungsten marker core and the air gap are replaced with ferromagnetic material. The ferromagnetic core produces heat when subjected to an alternating electromagnetic (EM) field and effectively shuts off after reaching the Curie temperature (TC) of the ferromagnetic material, thus establishing temperature self-regulation. The seed has a ferromagnetic Ni-Cu alloy core having a Curie transition at a temperature of 52 °C. This study summarizes the design and development of the self regulating ferromagnetic core TB seed for the concurrent hyperthermia and brachytherapy treatments. An experimental study of the magnetic properties of the Ni1-xCu x (0.28? x ?0.3) alloys, and the simulation studies of radiation and thermal distribution properties of the seed have been performed. A preliminary experiment for the ferromagnetic induction heating of Ni-Cu needles has been carried out to ensure the practical feasibility of the induction heating. Radiation dose characterizing parameters (dose rate constant and other TG-43 factors) were calculated using the Monte Carlo method. For the thermal characteristics, we studied a model consisting of single or multiple seeds placed in the central region of a cylindrical phantom using a finite-element analysis method, with and without considering the effect of the blood perfusion. The experimental study of the Ni-Cu alloys shows that heat treatment has a strong influence on the magnetic properties of the Ni-Cu alloy. The Curie transition temperature of the Ni1-xCux alloy decreases drastically with an increase in copper composition in the alloy. The study of the thermal expansion properties of the seed materials in the range of 37°C to 60°C shows negligible change in dimension due to the change of the temperature during the treatment. Imaging studies using CT and plane X-ray radiographs on the other hand, demonstrated that the new seed preserves the radiographic properties of the standard BEST seed model 2301 and is realistic for clinical use. The modification of the internal structure of the seed slightly changes dose rate and other TG-43 factors characterizing radiation distribution. The thermal modeling results show that the temperature of the seed surface rises rapidly and stays constant around TC of the ferromagnetic material. The amount of heat produced by the ferromagnetic core is sufficient to raise the temperature of the surrounding phantom to the therapeutic range. The volume of the phantom reaching the therapeutic temperature range increases with the increase in frequency or magnetic field strength. An isothermal distribution closely matching the radiation isodose distribution can be achieved within a target volume by tuning the frequency and intensity of the alternating magnetic field. The effect of heat loss due to the blood perfusion in a living tissue can be compensated by adjusting the magnetic field parameter. The results of the preliminary induction heating experiment conducted in a ham slice (implanted with ferromagnetic needles) demonstrated practical feasibility of induction heating and thermal self regulating property of the ferromagnetic Ni-Cu alloy. Modeling studies of the radiation and thermal properties of the TB seed show that the therapeutic implementation of the concurrent hyperthermia and brachytherapy treatment of the tumor is feasible. The see

  10. 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 ?/?= 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.Conclusions: For cervical cancer patients, D-RSBT can boost HR-CTV D{sub 90} over IS + ICBT and S-RSBT without violating the tolerance doses to the bladder, rectum, or sigmoid. The D{sub 90} improvements from D-RSBT depend on the patient, the delivery time budget, and the applicator structure.

  11. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition

    SciTech Connect

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Bloemen-Van Gurp, Esther; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank

    2010-10-15

    Purpose: The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: {sup 125}I, {sup 103}Pd, {sup 131}Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D{sub w,m} as opposed to dose to a small mass of medium in medium D{sub m,m}. Methods: Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using {sup 125}I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D{sub 90} values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using {sup 103}Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D{sub 90} values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results: Results from simulation (1) show that variations in the mean compositions of tissues affect low energy brachytherapy dosimetry. Dose differences between mean and one standard deviation of the mean composition increasing with distance from the source are observed. It is established that the {sup 125}I and {sup 131}Cs sources are the least sensitive to variations in elemental compositions while {sup 103}Pd is most sensitive. The EBS falls in between and exhibits complex behavior due to significant spectral hardening. Results from simulation (2) show that two prostate compositions are dosimetrically equivalent to water while the third shows D{sub 90} differences of up to 4%. Results from simulation (3) show that breast is more sensitive than prostate with dose variations of up to 30% from water for 70% adipose/30% gland breast. The variability of the breast composition adds a {+-}10% dose variation. Conclusions: Low energy brachytherapy dose distributions in tissue differ from water and are influenced by density, mean tissue composition, and patient-to-patient composition variations. The results support the use of a dose calculation algorithm accounting for heterogeneities such as MC. Since this work shows that variations in mean tissue compositions affect MC dosimetry and result in increased dose uncertainties, the authors conclude that imaging tools providing more accurate estimates of elemental compositions such as dual energy CT would be beneficial.

  12. Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

    SciTech Connect

    Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc; Létourneau, Mélanie; Fenster, Aaron; Pouliot, Jean

    2013-11-15

    Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then be generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because the computation time decrease with the number of points and that no effects were observed on the dosimetric indices when varying the number of sampling points and the number of iterations, they were respectively fixed to 2500 and to 100. The computation time to obtain ten complete treatments plans ranging from 9 to 18 catheters, with the corresponding dosimetric indices, was 90 s. However, 93% of the computation time is used by a research version of IPSA. For the breast, on average, the Radiation Therapy Oncology Group recommendations would be satisfied down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of V100, dose homogeneity index, and D90.Conclusions: The authors have devised a simple, fast and efficient method to optimize the number and position of catheters in interstitial HDR brachytherapy. The method was shown to be robust for both prostate and breast HDR brachytherapy. More importantly, the computation time of the algorithm is acceptable for clinical use. Ultimately, this catheter optimization algorithm could be coupled with a 3D ultrasound system to allow real-time guidance and planning in HDR brachytherapy.

  13. Screening for Prostate Cancer

    MedlinePLUS

    ... for Primary Care Practice Published Recommendations Draft Summary Prostate Cancer: Screening Release Date: May 2012 This topic is ... against prostate-specific antigen (PSA)-based screening for prostate cancer. The USPSTF recommends against the service. There is ...

  14. Localized Prostate Cancer

    MedlinePLUS

    ... a decision aid for men with clinically localized prostate cancer (available at http://effectivehealthcare.ahrq.gov/prostate_da) ... A Decision Aid for Men With Clinically Localized Prostate Cancer Page 1 of 24 Introduction Men with clinically ...

  15. Prostate Cancer Screening

    MedlinePLUS

    ... prostate. The prostate is a gland in the male reproductive system located just below the bladder (the organ that ... up part of semen . Enlarge Anatomy of the male reproductive and urinary systems, showing the prostate, testicles, bladder, and other organs. ...

  16. Current Brachytherapy Quality Assurance Guidance: Does It Meet the Challenges of Emerging Image-Guided Technologies?

    SciTech Connect

    Williamson, Jeffrey F.

    2008-05-01

    In the past decade, brachytherapy has shifted from the traditional surgical paradigm to more modern three-dimensional image-based planning and delivery approaches. The role of intraoperative and multimodality image-based planning is growing. Published American Association of Physicists in Medicine, American College of Radiology, European Society for Therapeutic Radiology and Oncology, and International Atomic Energy Agency quality assurance (QA) guidelines largely emphasize the QA of planning and delivery devices rather than processes. These protocols have been designed to verify compliance with major performance specifications and are not risk based. With some exceptions, complete and clinically practical guidance exists for sources, QA instrumentation, non-image-based planning systems, applicators, remote afterloading systems, dosimetry, and calibration. Updated guidance is needed for intraoperative imaging systems and image-based planning systems. For non-image-based brachytherapy, the American Association of Physicists in Medicine Task Group reports 56 and 59 provide reasonable guidance on procedure-specific process flow and QA. However, improved guidance is needed even for established procedures such as ultrasound-guided prostate implants. Adaptive replanning in brachytherapy faces unsolved problems similar to that of image-guided adaptive external beam radiotherapy.

  17. Impact of using linear optimization models in dose planning for HDR brachytherapy

    SciTech Connect

    Holm, Aasa; Larsson, Torbjoern; Carlsson Tedgren, Aasa

    2012-02-15

    Purpose: Dose plans generated with optimization models hitherto used in high-dose-rate (HDR) brachytherapy have shown a tendency to yield longer dwell times than manually optimized plans. Concern has been raised for the corresponding undesired hot spots, and various methods to mitigate these have been developed. The hypotheses upon this work is based are (a) that one cause for the long dwell times is the use of objective functions comprising simple linear penalties and (b) that alternative penalties, as these are piecewise linear, would lead to reduced length of individual dwell times. Methods: The characteristics of the linear penalties and the piecewise linear penalties are analyzed mathematically. Experimental comparisons between the two types of penalties are carried out retrospectively for a set of prostate cancer patients. Results: When the two types of penalties are compared, significant changes can be seen in the dwell times, while most dose-volume parameters do not differ significantly. On average, total dwell times were reduced by 4.2%, with a reduction of maximum dwell times by 25%, when the alternative penalties were used. Conclusions: The use of linear penalties in optimization models for HDR brachytherapy is one cause for the undesired long dwell times that arise in mathematically optimized plans. By introducing alternative penalties, a significant reduction in dwell times can be achieved for HDR brachytherapy dose plans. Although various measures for mitigating the long dwell times are already available, the observation that linear penalties contribute to their appearance is of fundamental interest.

  18. Accuracy of needle implantation in brachytherapy using a medical AR system: a phantom study

    NASA Astrophysics Data System (ADS)

    Wesarg, Stefan; Firle, Evelyn A.; Schwald, Bernd; Seibert, Helmut; Zogal, Pawel; Roeddiger, Sandra

    2004-05-01

    Brachytherapy is the treatment method of choice for patients with a tumor relapse after a radiation therapy with external beams or tumors in regions with sensitive surrounding organs-at-risk, e. g. prostate tumors. The standard needle implantation procedure in brachytherapy uses pre-operatively acquired image data displayed as slices on a monitor beneath the operation table. Since this information allows only a rough orientation for the surgeon, the position of the needles has to be verified repeatedly during the intervention. Within the project Medarpa a transparent display being the core component of a medical Augmented Reality (AR) system has been developed. There, pre-operatively acquired image data is displayed together with the position of the tracked instrument allowing a navigated implantation of the brachytherapy needles. The surgeon is enabled to see the anatomical information as well as the virtual instrument in front of the operation area. Thus, the Medarpa system serves as "window into the patient". This paper deals with the results of first clinical trials of the system. Phantoms have been used for evaluating the achieved accuracy of the needle implantation. This has been done by comparing the output of the system (instrument positions relative to the phantom) with the real positions of the needles measured by means of a verification CT scan.

  19. An innovative dosimetric model for formulating a semi-analytical solution for the activity-volume relationship in prostate implants

    SciTech Connect

    Lee, Plato C.; Parks, Eric K.; Moran, Brian J

    2003-12-31

    An innovative (and yet simple) dosimetric model is proposed that provides a semi-analytical solution to the total activity-volume relationship in ultrasound-guided transperineal prostate implant. This dosimetric model is based on 4 simple assumptions. First, the prostate target volume is approximated as a sphere. Second, the urethra is presumed to transverse through the center of the prostate target volume. Third, peripheral loading is applied as the seed-loading technique. Fourth, as the major innovation of the proposed model, the radial dose function of the Iodine-125 {sup 125}I seed is forced to fit a simple power function of the distance r. Pursuant to the third assumption, the peripherally-loaded seeds also define a spherical volume defined as the loading volume w. Also pursuant to the fourth assumption, the radial dose function is expressed as 1.139*r{sup -0.474} for r = 1.5 to 2.5 cm. Thereafter, a simple analytical power-law equation, A = 1.630* w{sup 0.825}, for the relationship between the total activity A in mCi and the loading volume w in cc is derived for {sup 125}I monotherapy. Isodose plans for loading volumes corresponding to r = 1.5, 1.8, 2.2, and 2.5 cm were performed. The maximal isodose coverage volume {sub max}V100 was calculated for each case and was found to be on the average 65% larger than the loading volume w. Matching prostate target volume V to the loading volume w therefore yields a generous implant (with a margin of approximately 3.3 mm). Conversely, matching the prostate target volume V to the {sub max}V100 yields a tight implant (with 0.0 mm or no margin). Matching the prostate target volume V to a midpoint between the loading volume w and {sub max}V100 yields a moderate implant (with approximately 1- to 2-mm margin). Three individual equations are derived for each type of implants: A = 1.630* V{sup 0.825}, A = 1.288* V{sup 0.825}, or A = 1.078 V{sup 0.825} for generous, tight, or moderate implants, respectively. Patient data at the Chicago Prostate Cancer Center are found to support the above dosimetric model and the 3 semi-analytically derived equations. The above equations are also compared favorably with some of the previously published equations from other authors. These results support the efficacy of the proposed dosimetric model.

  20. Clinical Trials of a Urethral Dose Measurement System in Brachytherapy Using Scintillation Detectors

    SciTech Connect

    Suchowerska, Natalka; Jackson, Michael; Lambert, Jamil; Yin, Yong Bai; Hruby, George; McKenzie, David R.

    2011-02-01

    Purpose: To report on the clinical feasibility of a novel scintillation detector system with fiberoptic readout that measures the urethral dose during high-dose-rate brachytherapy treatment of the prostate. Methods and Materials: The clinical trial enrolled 24 patients receiving high-dose-rate brachytherapy treatment to the prostate. After the first 14 patients, three improvements were made to the dosimeter system design to improve clinical reliability: a dosimeter self-checking facility; a radiopaque marker to determine the position of the dosimeter, and a more robust optical extension fiber. Results: Improvements to the system design allowed for accurate dose measurements to be made in vivo. A maximum measured dose departure of 9% from the calculated dose was observed after dosimeter design improvements. Conclusions: Departures of the measured from the calculated dose, after improvements to the dosimetry system, arise primarily from small changes in patient anatomy. Therefore, we recommend that patient response be correlated with the measured in vivo dose rather than with the calculated dose.

  1. Matching and reconstruction of brachytherapy seeds using the Hungarian algorithm (MARSHAL)

    SciTech Connect

    Jain, Ameet Kumar; Zhou, Yu; Mustufa, Tabish; Clif Burdette, E.; Chirikjian, Gregory S.; Fichtinger, Gabor

    2005-11-15

    Intraoperative dosimetric quality assurance in prostate brachytherapy critically depends on discerning the three-dimensional (3D) locations of implanted seeds. The ability to reconstruct the implanted seeds intraoperatively will allow us to make immediate provisions for dosimetric deviations from the optimal implant plan. A method for seed reconstruction from segmented C-arm fluoroscopy images is proposed. The 3D coordinates of the implanted seeds can be calculated upon resolving the correspondence of seeds in multiple x-ray images. We formalize seed-matching as a combinatorial optimization problem, which has salient features: (a) extensively studied solutions by the computer science community; (b) proof for the nonexistence of any polynomial time exact algorithm; and (c) a practical pseudo-polynomial algorithm that mostly runs in O(N{sup 3}) time using any number of images. We prove that two images are insufficient to correctly match the seeds, while a third image renders the matching problem to be of nonpolynomial complexity. We utilize the special structure of the problem and propose a pseudopolynomial time algorithm. Using three presegmented images, matching and reconstruction of brachytherapy seeds using the Hungarian algorithm achieved complete matching in simulation experiments; and 98.5% in phantom experiments. 3D reconstruction error for correctly matched seeds has a mean of 0.63 mm, and 0.9 mm for incorrectly matched seeds. The maximum seed reconstruction error in each implant was typically around 1.32 mm. Both on synthetic data and in phantom experiments, matching rate and reconstruction error achieved using presegmented images was found to be sufficient for prostate brachytherapy. The algorithm is extendable to deal with arbitrary number of images without any loss in speed or accuracy. The algorithm is sufficiently generic to provide a practical solution to any correspondence problem, across different imaging modalities and features.

  2. Time to failure after definitive therapy for prostate cancer: implications for importance of aggressive local treatment

    PubMed Central

    Taira, Al V.; Butler, Wayne M.; Galbreath, Robert W.; Fiano, Ryan; Wallner, Kent E.; Adamovich, Edward

    2013-01-01

    Purpose To explore patterns of time to failure in men receiving high doses of permanent seed brachytherapy with or without external beam radiation therapy as a function of risk status. Material and methods Two thousand two hundred and thirty four patients were treated with prostate brachytherapy with median follow up of 8.0 years. The population was 35% low risk, 49% intermediate risk, and 16% high risk (NCCN). Median day 0 implant D90 was 119% and V100 was 98%. Treatment failure was defined as PSA > 0.40 ng/mL after nadir. Rates of biochemical failure, distant metastases, and prostate cancer death were determined with non-prostate death as a competing risk. Results For all patients, the 10-year biochemical failure, distant metastases, and cause-specific mortality were 4.4%, 1.4%, and 1.3%, respectively. The biochemical failure rates were 1.3%, 4.8%, and 10.0% for men with low, intermediate, and high risk disease, respectively. Median time to failure was 2.8 years. In men who died from prostate cancer, the median time from treatment failure to death was 4.2 years. Overall, 83% of biochemical failures and 97% of metastases occurred within the first 4 years after treatment. Conclusions With the dose escalation achieved by high quality brachytherapy dosimetry, even high-risk prostate cancer patients have excellent long term biochemical outcomes. Treatment failures occur early, and one third become metastatic and progress rapidly to prostate cancer death. The low frequency and pattern of failures suggest the presence of micrometastatic disease prior to treatment is rare, even in high risk patients. PMID:24474970

  3. Prostate Enlargement: Benign Prostatic Hyperplasia (BPH)

    MedlinePLUS

    ... shaped gland that is part of the male reproductive system. The main function of the prostate is to ... shaped gland that is part of the male reproductive system. [ Top ] What causes benign prostatic hyperplasia? The cause ...

  4. Intraoperative dynamic dosimetry for prostate implants

    NASA Astrophysics Data System (ADS)

    Todor, D. A.; Zaider, M.; Cohen, G. N.; Worman, M. F.; Zelefsky, M. J.

    2003-05-01

    This paper describes analytic tools in support of a paradigm shift in brachytherapy treatment planning for prostate cancer - a shift from standard pre-planning to intraoperative planning using dosimetric feedback based on the actual deposited seed positions within the prostate. The method proposed is guided by several desiderata: (a) bringing both planning and evaluation in the operating room (i.e. make post-implant evaluation superfluous) therefore making rectifications - if necessary - still achievable; (b) making planning and implant evaluation consistent by using the same imaging system (ultrasound); and (c) using only equipment commonly found in a hospital operating room. The intraoperative dosimetric evaluation is based on the fusion between ultrasound images and 3D seed coordinates reconstructed from fluoroscopic projections. Automatic seed detection and registration of the fluoroscopic and ultrasound information, two of the three key ingredients needed for the intraoperative dynamic dosimetry optimization (IDDO), are explained in detail. The third one, the reconstruction of 3D coordinates from projections, was reported in a previous article. The algorithms were validated using a custom-designed phantom with non-radioactive (dummy) seeds. Also, fluoroscopic images were taken at the conclusion of an actual permanent prostate implant and compared with data on the same patient obtained from radiographic-based post-implant evaluation. To offset the effect of organ motion the comparison was performed in terms of the proximity function of the two seed distributions. The agreement between the intra- and post-operative seed distributions was excellent.

  5. Whole-Pelvic Nodal Radiation Therapy in the Context of Hypofractionation for High-Risk Prostate Cancer Patients: A Step Forward

    SciTech Connect

    Kaidar-Person, Orit; Roach, Mack; Créhange, Gilles

    2013-07-15

    Given the low ?/? ratio of prostate cancer, prostate hypofractionation has been tested through numerous clinical studies. There is a growing body of literature suggesting that with high conformal radiation therapy and even with more sophisticated radiation techniques, such as high-dose-rate brachytherapy or image-guided intensity modulated radiation therapy, morbidity associated with shortening overall treatment time with higher doses per fraction remains low when compared with protracted conventional radiation therapy to the prostate only. In high-risk prostate cancer patients, there is accumulating evidence that either dose escalation to the prostate or hypofractionation may improve outcome. Nevertheless, selected patients who have a high risk of lymph node involvement may benefit from whole-pelvic radiation therapy (WPRT). Although combining WPRT with hypofractionated prostate radiation therapy is feasible, it remains investigational. By combining modern advances in radiation oncology (high-dose-rate prostate brachytherapy, intensity modulated radiation therapy with an improved image guidance for soft-tissue sparing), it is hypothesized that WPRT could take advantage of recent results from hypofractionation trials. Moreover, the results from hypofractionation trials raise questions as to whether hypofractionation to pelvic lymph nodes with a high risk of occult involvement might improve the outcomes in WPRT. Although investigational, this review discusses the challenging idea of WPRT in the context of hypofractionation for patients with high-risk prostate cancer.

  6. Clinical implementation of a new electronic brachytherapy system for skin brachytherapy

    PubMed Central

    Ballester-Sánchez, Rosa; Celada-Álvarez, Francisco Javier; Candela-Juan, Cristian; García-Martínez, Teresa; Llavador-Ros, Margarita; Botella-Estrada, Rafael; Barker, Christopher A.; Ballesta, Antonio; Tormo-Micó, Alejandro; Rodríguez, Silvia; Perez-Calatayud, Jose

    2014-01-01

    Although surgery is usually the first-line treatment for nonmelanoma skin cancers, radiotherapy (RT) may be indicated in selected cases. Radiation therapy as primary therapy can result in excellent control rates, cosmetics, and quality of life. Brachytherapy is a radiation treatment modality that offers the most conformal option to patients. A new modality for skin brachytherapy is electronic brachytherapy. This involves the placement of a high dose rate X-ray source directly in a skin applicator close to the skin surface, and therefore combines the benefits of brachytherapy with those of low energy X-ray radiotherapy. The Esteya electronic brachytherapy system is specifically designed for skin surface brachytherapy procedures. The purpose of this manuscript is to describe the clinical implementation of the new Esteya electronic brachytherapy system, which may provide guidance for users of this system. The information covered includes patient selection, treatment planning (depth evaluation and margin determination), patient marking, and setup. The justification for the hypofractionated regimen is described and compared with others protocols in the literature. Quality assurance (QA) aspects including daily testing are also included. We emphasize that these are guidelines, and clinical judgment and experience must always prevail in the care of patients, as with any medical treatment. We conclude that clinical implementation of the Esteya brachytherapy system is simple for patients and providers, and should allow for precise and safe treatment of nonmelanoma skin cancers. PMID:25834587

  7. CISNET: Prostate Cancer Modeling

    Cancer.gov

    The CISNET prostate group grew from a single team in 2000, to two teams in 2002, to three teams in 2005. The group’s interests include the natural history of the disease and its potential implications for the efficacy of the prostate-specific antigen (PSA) screening test, screening policy, overdiagnosis, novel prostate cancer biomarkers, patterns and outcomes of prostate cancer care, and health disparities in prostate cancer screening and treatment.

  8. The difference of scoring dose to water or tissues in Monte Carlo dose calculations for low energy brachytherapy photon sources

    SciTech Connect

    Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-03-15

    Purpose: The goal of this work is to compare D{sub m,m} (radiation transported in medium; dose scored in medium) and D{sub w,m} (radiation transported in medium; dose scored in water) obtained from Monte Carlo (MC) simulations for a subset of human tissues of interest in low energy photon brachytherapy. Using low dose rate seeds and an electronic brachytherapy source (EBS), the authors quantify the large cavity theory conversion factors required. The authors also assess whether applying large cavity theory utilizing the sources' initial photon spectra and average photon energy induces errors related to spatial spectral variations. First, ideal spherical geometries were investigated, followed by clinical brachytherapy LDR seed implants for breast and prostate cancer patients. Methods: Two types of dose calculations are performed with the GEANT4 MC code. (1) For several human tissues, dose profiles are obtained in spherical geometries centered on four types of low energy brachytherapy sources: {sup 125}I, {sup 103}Pd, and {sup 131}Cs seeds, as well as an EBS operating at 50 kV. Ratios of D{sub w,m} over D{sub m,m} are evaluated in the 0-6 cm range. In addition to mean tissue composition, compositions corresponding to one standard deviation from the mean are also studied. (2) Four clinical breast (using {sup 103}Pd) and prostate (using {sup 125}I) brachytherapy seed implants are considered. MC dose calculations are performed based on postimplant CT scans using prostate and breast tissue compositions. PTV D{sub 90} values are compared for D{sub w,m} and D{sub m,m}. Results: (1) Differences (D{sub w,m}/D{sub m,m}-1) of -3% to 70% are observed for the investigated tissues. For a given tissue, D{sub w,m}/D{sub m,m} is similar for all sources within 4% and does not vary more than 2% with distance due to very moderate spectral shifts. Variations of tissue composition about the assumed mean composition influence the conversion factors up to 38%. (2) The ratio of D{sub 90(w,m)} over D{sub 90(m,m)} for clinical implants matches D{sub w,m}/D{sub m,m} at 1 cm from the single point sources. Conclusions: Given the small variation with distance, using conversion factors based on the emitted photon spectrum (or its mean energy) of a given source introduces minimal error. The large differences observed between scoring schemes underline the need for guidelines on choice of media for dose reporting. Providing such guidelines is beyond the scope of this work.

  9. Transurethral resection of the prostate

    MedlinePLUS

    TURP; Prostate resection - transurethral ... used to remove the inside part of your prostate gland using electricity. ... if you have benign prostatic hyperplasia ( BPH ). The prostate gland often grows larger as men get older. ...

  10. Dosimetric comparison between model 9011 and 6711 sources in prostate implants

    SciTech Connect

    Zhang, Hualin; Beyer, David

    2013-07-01

    The purpose of this work is to evaluate the model 9011 iodine-125 ({sup 125}I) in prostate implants by comparing dosimetric coverage provided by the 6711 vs 9011 source implants. Postimplant dosimetry was performed in 18 consecutively implanted patients with prostate cancer. Two were implanted with the 9011 source and 16 with the 6711 source. For purposes of comparison, each implant was then recalculated assuming use of the other source. The same commercially available planning system was used and the specific source data for both 6711 and 9011 products were entered. The results of these calculations are compared side by side in the terms of the isodose values covering 100% (D100) and 90% (D90) of prostate volume, and the percentages of volumes of prostate, bladder, rectum, and urethra covered by 200% (V200), 150% (V150), 100% (V100), 50% (V50), and 20% (V20) of the prescribed dose as well. The 6711 source data overestimate coverage by 6.4% (ranging from 4.9% to 6.9%; median 6.6%) at D100 and by 6.6% (ranging from 6.2% to 6.8%; median 6.6%) at D90 compared with actual 9011 data. Greater discrepancies of up to 67% are seen at higher dose levels: average reduction for V100 is 2.7% (ranging from 0.6% to 7.7%; median 2.3%), for V150 is 14.6% (ranging from 6.1% to 20.5%; median 15.3%), for V200 is 14.9% (ranging from 4.8% to 19.1%; median 16%); similarly seen in bladder, rectal, and urethral coverage. This work demonstrates a clear difference in dosimetric behavior between the 9011 and 6711 sources. Using the 6711 source data for 9011 source implants would create a pronounced error in dose calculation. This study provides evidence that the 9011 source can provide the same dosimetric quality as the 6711 source, if properly used; however, the 6711 source data should not be considered as a surrogate for the 9011 source implants.

  11. {sup 106}Ruthenium Brachytherapy for Retinoblastoma

    SciTech Connect

    Abouzeid, Hana; Moeckli, Raphael; Gaillard, Marie-Claire; Beck-Popovic, Maja; Pica, Alessia; Zografos, Leonidas; Balmer, Aubin; Pampallona, Sandro; Munier, Francis L.

    2008-07-01

    Purpose: To evaluate the efficacy of {sup 106}Ru plaque brachytherapy for the treatment of retinoblastoma. Methods and Materials: We reviewed a retrospective, noncomparative case series of 39 children with retinoblastoma treated with {sup 106}Ru plaques at the Jules-Gonin Eye Hospital between October 1992 and July 2006, with 12 months of follow-up. Results: A total of 63 tumors were treated with {sup 106}Ru brachytherapy in 41 eyes. The median patient age was 27 months. {sup 106}Ru brachytherapy was the first-line treatment for 3 tumors (4.8%), second-line treatment for 13 (20.6%), and salvage treatment for 47 tumors (74.6%) resistant to other treatment modalities. Overall tumor control was achieved in 73% at 1 year. Tumor recurrence at 12 months was observed in 2 (12.5%) of 16 tumors for which {sup 106}Ru brachytherapy was used as the first- or second-line treatment and in 15 (31.9%) of 47 tumors for which {sup 106}Ru brachytherapy was used as salvage treatment. Eye retention was achieved in 76% of cases (31 of 41 eyes). Univariate and multivariate analyses revealed no statistically significant risk factors for tumor recurrence. Radiation complications included retinal detachment in 7 (17.1%), proliferative retinopathy in 1 (2.4%), and subcapsular cataract in 4 (9.7%) of 41 eyes. Conclusion: {sup 106}Ru brachytherapy is an effective treatment for retinoblastoma, with few secondary complications. Local vitreous seeding can be successfully treated with {sup 106}Ru brachytherapy.

  12. Brachytherapy in the Treatment of Cholangiocarcinoma

    SciTech Connect

    Shinohara, Eric T.; Guo Mengye; Mitra, Nandita; Metz, James M.

    2010-11-01

    Purpose: To examine the role of brachytherapy in the treatment of cholangiocarcinomas in a relatively large group of patients. Methods and Materials: Using the Surveillance, Epidemiology and End Results database, a total of 193 patients with cholangiocarcinoma treated with brachytherapy were identified for the period 1988-2003. The primary analysis compared patients treated with brachytherapy (with or without external-beam radiation) with those who did not receive radiation. To try to account for confounding variables, propensity score and sensitivity analyses were used. Results: There was a significant difference between patients who received radiation (n = 193) and those who did not (n = 6859) with regard to surgery (p < 0.0001), race (p < 0.0001), stage (p < 0.0001), and year of diagnosis (p <0.0001). Median survival for patients treated with brachytherapy was 11 months (95% confidence interval [CI] 9-13 months), compared with 4 months for patients who received no radiation (p < 0.0001). On multivariable analysis (hazard ratio [95% CI]) brachytherapy (0.79 [0.66-0.95]), surgery (0.50 [0.46-0.53]), year of diagnosis (1998-2003: 0.66 [0.60-0.73]; 1993-1997: (0.96 [0.89-1.03; NS], baseline 1988-1992), and extrahepatic disease (0.84 [0.79-0.89]) were associated with better overall survival. Conclusions: To the authors' knowledge, this is the largest dataset reported for the treatment of cholangiocarcinomas with brachytherapy. The results of this retrospective analysis suggest that brachytherapy may improve overall survival. However, because of the limitations of the Surveillance, Epidemiology and End Results database, these results should be interpreted cautiously, and future prospective studies are needed.

  13. Prostate Cancer.

    PubMed

    Talcott, James A

    2015-12-01

    This issue provides a clinical overview of prostate cancer, focusing on prevention, screening, diagnosis, staging, shared decision making, consultation, the role of primary care providers, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers. PMID:26618297

  14. An automated intensity-weighted brachytherapy seed localization algorithm

    SciTech Connect

    Whitehead, Gregory; Chang Zheng; Ji, Jim

    2008-03-15

    Brachytherapy has proven to be an effective treatment for various forms of cancer, whereby radioactive material is inserted directly into the body to maximize dosage to malignant tumors while preserving healthy tissue. In order to validate the preoperative or intraoperative dosimetric model, a postimplant evaluation procedure is needed to ensure that the locations of the implanted seeds are consistent with the planning stage. Moreover, development of an automated algorithm for seed detection and localization is necessary to expedite the postimplant evaluation process and reduce human error. Most previously reported algorithms have performed binary transforms on images before attempting to localize seeds. Furthermore, traditional approaches based upon three-dimensional seed shape parameterization and matching require high resolution imaging. The authors propose a new computationally efficient algorithm for automatic seed localization for full three-dimensional, low-resolution data sets that directly applies voxel intensity to the estimation of both seed centroid location and angular seed orientation. Computer simulations, phantom studies, and in vivo computed tomography prostate seed imaging results show that the proposed algorithm can produce reliable results even for low-resolution images.

  15. Image guided Brachytherapy: The paradigm of Gynecologic and Partial Breast HDR Brachytherapy

    NASA Astrophysics Data System (ADS)

    Diamantopoulos, S.; Kantemiris, I.; Konidari, A.; Zaverdinos, P.

    2015-09-01

    High dose rate (HDR) brachytherapy uses high strength radioactive sources and temporary interstitial implants to conform the dose to target and minimize the treatment time. The advances of imaging technology enable accurate reconstruction of the implant and exact delineation of high-risk CTV and the surrounding critical structures. Furthermore, with sophisticated treatment planning systems, applicator devices and stepping source afterloaders, brachytherapy evolved to a more precise, safe and individualized treatment. At the Radiation Oncology Department of Metropolitan Hospital Athens, MRI guided HDR gynecologic (GYN) brachytherapy and accelerated partial breast irradiation (APBI) with brachytherapy are performed routinely. Contouring and treatment planning are based on the recommendations of the GEC - ESTRO Working group. The task of this presentation is to reveal the advantages of 3D image guided brachytherapy over 2D brachytherapy. Thus, two patients treated at our department (one GYN and one APBI) will be presented. The advantage of having adequate dose coverage of the high risk CTV and simultaneous low doses to the OARs when using 3D image- based brachytherapy will be presented. The treatment techniques, equipment issues, as well as implantation, imaging and treatment planning procedures will be described. Quality assurance checks will be treated separately.

  16. [Salvage treatments following prostate radiation therapy: role of the urologist].

    PubMed

    Soulié, M; Salomon, L

    2014-10-01

    The management of recurrent prostate cancer after radiotherapy or brachytherapy is non-standardized and rapidly evolving. Local recurrence is observed on average in 30% of cases several years following irradiation. A key challenge is to determine the site of recurrence and imaging (MRI and PET choline) coupled to prostate biopsies are important to confirm the local character. Salvage therapy performed by the urologist can then control the situation. Radical prostatectomy subject to strict technical conditions is one of the most efficient local treatments, however it comes at the cost of significant urinary morbidity; minimally invasive therapies (focused ultrasound and cryotherapy) have also their place in specific indications. Each clinical situation should be discussed in pluridisciplinary meetings integrating the oncologic and functional status at recurrence, the risk/benefit ratio of each treatment, the patient's wishes and probability of survival. PMID:25175343

  17. AAPM and GEC-ESTRO guidelines for image-guided robotic brachytherapy: Report of Task Group 192

    SciTech Connect

    Podder, Tarun K.; Beaulieu, Luc; Caldwell, Barrett; Cormack, Robert A.; Crass, Jostin B.; Dicker, Adam P.; Yu, Yan; Fenster, Aaron; Fichtinger, Gabor; Meltsner, Michael A.; Moerland, Marinus A.; Nath, Ravinder; Rivard, Mark J.; Salcudean, Tim; Song, Danny Y.; Thomadsen, Bruce R.

    2014-10-15

    In the last decade, there have been significant developments into integration of robots and automation tools with brachytherapy delivery systems. These systems aim to improve the current paradigm by executing higher precision and accuracy in seed placement, improving calculation of optimal seed locations, minimizing surgical trauma, and reducing radiation exposure to medical staff. Most of the applications of this technology have been in the implantation of seeds in patients with early-stage prostate cancer. Nevertheless, the techniques apply to any clinical site where interstitial brachytherapy is appropriate. In consideration of the rapid developments in this area, the American Association of Physicists in Medicine (AAPM) commissioned Task Group 192 to review the state-of-the-art in the field of robotic interstitial brachytherapy. This is a joint Task Group with the Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology (GEC-ESTRO). All developed and reported robotic brachytherapy systems were reviewed. Commissioning and quality assurance procedures for the safe and consistent use of these systems are also provided. Manual seed placement techniques with a rigid template have an estimated in vivo accuracy of 3–6 mm. In addition to the placement accuracy, factors such as tissue deformation, needle deviation, and edema may result in a delivered dose distribution that differs from the preimplant or intraoperative plan. However, real-time needle tracking and seed identification for dynamic updating of dosimetry may improve the quality of seed implantation. The AAPM and GEC-ESTRO recommend that robotic systems should demonstrate a spatial accuracy of seed placement ?1.0 mm in a phantom. This recommendation is based on the current performance of existing robotic brachytherapy systems and propagation of uncertainties. During clinical commissioning, tests should be conducted to ensure that this level of accuracy is achieved. These tests should mimic the real operating procedure as closely as possible. Additional recommendations on robotic brachytherapy systems include display of the operational state; capability of manual override; documented policies for independent check and data verification; intuitive interface displaying the implantation plan and visualization of needle positions and seed locations relative to the target anatomy; needle insertion in a sequential order; robot–clinician and robot–patient interactions robustness, reliability, and safety while delivering the correct dose at the correct site for the correct patient; avoidance of excessive force on radioactive sources; delivery confirmation of the required number or position of seeds; incorporation of a collision avoidance system; system cleaning, decontamination, and sterilization procedures. These recommendations are applicable to end users and manufacturers of robotic brachytherapy systems.

  18. [A CASE OF PROSTATE CANCER WITH UNUSUAL PATTERN OF RECURRENCE AFTER RADIOTHERAPY].

    PubMed

    Oshinomi, Kazuhiko; Fukagai, Takashi; Ogawa, Yu; Sato, Naoya; Morita, Jun; Aso, Takayuki; Igarashi, Atsushi; Morita, Masashi; Naoe, Michio; Fuji, Kohzo; Ogawa, Yoshio

    2015-01-01

    An 82-year-old man underwent radiotherapy (brachytherapy, external beam radiotherapy) for prostate cancer, followed approximately five years later by endocrine therapy for biochemical recurrence, which controlled the prostate-specific antigen (PSA) level. His later admission due to severe gross hematuria and dysuria is described. Computed tomography and magnetic resonance imaging findings revealed a cystic tumor continuous with the prostate between the prostate and rectum, and this tumor was thought to be the cause of the hematuria and dysuria. Transrectal biopsy and transurethral resection of the prostate were performed for pathological diagnosis and improvement of dysuria. The pathological diagnosis was remnant prostate cancer, and the cystic tumor was thought to have developed as a result of prostate cancer recurrence. Although chemotherapy using docetaxel was considered postoperatively, the patient refused this treatment. Even though the PSA level was under control, the patient's condition progressed rapidly, with onset of pulmonary and cervical lymph node metastases within a short period of time, and the patient subsequently died. PMID:26399130

  19. Transurethral ultrasound of the prostrate for applications in prostrate brachytherapy: analysis of phantom and in-vivo data

    NASA Astrophysics Data System (ADS)

    Holmes, David R., III; Davis, Brian J.; Bruce, Charles; Wilson, Torrence; Robb, Richard A.

    2001-05-01

    3D Trans-Urethral Ultrasound (TUUS) imaging is a new imaging technique for the diagnosis and treatment of prostate disease. Our current research focuses on the potential of TUUS in therapy guidance during tansperineal interstitial permanent prostate brachytherapy (TIPPB). TUUS may complement of potentially replace x-ray fluoroscopy and TRUS in providing data for determining the prostate boundary and radiation source locations. Prostate boundary detection and source localization using TUUS were tested on an ultrasound- equivalent prostate phantom and ina patient during TIPPB. Data collection was conducted with a 10 French, 10 MHz ultrasound catheter controlled by an Acuson SequoiaTM workstation. 2D and 3D TUUS scans were acquired after radioactive seeds were placed in the phantom and in the patient. Data was reconstructed, processed, and analyzed using Analyze software. Segmentation of the prostate boundary was performed semi-automatically, and seed segmentation was performed manually. Image artifacts in TUUS data resulted in incorrect reconstruction of the seeds. Intelligent processing of the seed data improved reconstruction. Comparison to the CT data suggests that TUUS dat provides: 1) greater spatial resolution, 2) greater temporal resolution and 3) better contrast for soft tissue differentiation. The reconstructed source sizes and locations were measured and found accurate. Placement of the TUUS catheter into the urethra provides excellent 2D sections which can be used to acquire volumetric data for 3D analysis of the prostate and radioactive sources. Preliminary results suggest that TUUS will be useful for guidance of seed placement, post-implant seed localization, and intra-operative dosimetry.

  20. Hypoxic Prostate/Muscle PO{sub 2} Ratio Predicts for Outcome in Patients With Localized Prostate Cancer: Long-Term Results

    SciTech Connect

    Turaka, Aruna; Buyyounouski, Mark K.; Hanlon, Alexandra L.; Horwitz, Eric M.; Greenberg, Richard E.; Movsas, Benjamin

    2012-03-01

    Purpose: To correlate tumor oxygenation status with long-term biochemical outcome after prostate brachytherapy. Methods and Materials: Custom-made Eppendorf PO{sub 2} microelectrodes were used to obtain PO{sub 2} measurements from the prostate (P), focused on positive biopsy locations, and normal muscle tissue (M), as a control. A total of 11,516 measurements were obtained in 57 men with localized prostate cancer immediately before prostate brachytherapy was given. The Eppendorf histograms provided the median PO{sub 2}, mean PO{sub 2}, and % <5 mm Hg or <10 mm Hg. Biochemical failure (BF) was defined using both the former American Society of Therapeutic Radiation Oncology (ASTRO) (three consecutive raises) and the current Phoenix (prostate-specific antigen nadir + 2 ng/mL) definitions. A Cox proportional hazards regression model evaluated the influence of hypoxia using the P/M mean PO{sub 2} ratio on BF. Results: With a median follow-up time of 8 years, 12 men had ASTRO BF and 8 had Phoenix BF. On multivariate analysis, P/M PO{sub 2} ratio <0.10 emerged as the only significant predictor of ASTRO BF (p = 0.043). Hormonal therapy (p = 0.015) and P/M PO{sub 2} ratio <0.10 (p = 0.046) emerged as the only independent predictors of the Phoenix BF. Kaplan-Meier freedom from BF for P/M ratio <0.10 vs. {>=}0.10 at 8 years for ASTRO BF was 46% vs. 78% (p = 0.03) and for the Phoenix BF was 66% vs. 83% (p = 0.02). Conclusions: Hypoxia in prostate cancer (low mean P/M PO{sub 2} ratio) significantly predicts for poor long-term biochemical outcome, suggesting that novel hypoxic strategies should be investigated.

  1. Outpatient vaginal cuff brachytherapy for endometrial cancer.

    PubMed

    Petereit, D. G.; Tannehill, S. P.; Grosen, E. A.; Hartenbach, E. M.; Schink, J. C.

    1999-11-01

    Petereit DG, Tannehill SP, Grosen EA, Hartenbach EM, Schink JC. Outpatient vaginal cuff brachytherapy for endometrial cancer. The objective of this study was to determine the efficacy and complications of postoperative high-dose-rate (HDR) vaginal-cuff brachytherapy (VCB) in patients with endometrial carcinoma. Between August 1989 to September 1997, 191 patients were treated postoperatively after a total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH/BSO) with outpatient adjuvant HDR VCB for low-risk endometrial cancer (IB-84%, grade 1 or 2-96%). Patients were treated with 2 HDR fractions, delivered one week apart while under conscious sedation (16.2 Gy X 2 to the vaginal surface). All clinical endpoints were calculated using the Kaplan Meier method. The median time in the brachytherapy suite was 60 min in which no acute complications were observed. The 30-day morbidity and mortality rates were both 0%. With a median follow-up of 38 months (12-82 months), the 4-year survival, relapse-free survival, and vaginal-control rates were 95%, 98%, and 100%, respectively. One patient developed a colo-vaginal fistula at 5 years. Adjuvant HDR VCB in 2 outpatient insertions produced 100% vaginal control rates with minimal morbidity. The advantages of high dose-rate compared to low dose-rate vaginal brachytherapy include patient convenience, markedly shorter treatment times (1 h per insertion), and reduction in the cost and potential morbidity of hospitalization. HDR brachytherapy approach is a cost-effective alternative to either low-dose-rate brachytherapy or whole pelvic radiotherapy in carefully selected patients. PMID:11240811

  2. The Prostate Health Index: Its Utility in Prostate Cancer Detection.

    PubMed

    Lepor, Abbey; Catalona, William J; Loeb, Stacy

    2016-02-01

    The Prostate Health Index is a Food and Drug Administration-approved blood test combining total, free, and [-2]pro prostate-specific antigen with greater specificity than free and total prostate-specific antigen for clinically significant prostate cancer. This article reviews the evidence on the performance of the Prostate Health Index to predict prostate biopsy outcome, its incorporation into multivariable risk-assessment tools, and its ability to predict prognosis after conservative management or prostate cancer treatment. PMID:26614024

  3. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ...Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting...occurring under an NRC licensee's permanent implant brachytherapy program. This interim policy...that are authorized to perform permanent implant brachytherapy. DATES: This policy...

  4. Enlarged prostate gland

    MedlinePLUS Videos and Cool Tools

    ... is encased within the prostate gland. As a man ages, the prostate typically enlarges in size in ... urinate, and incontinence. Less than half of all men with BPH have symptoms of the disease, or ...

  5. Screening for Prostate Cancer

    MedlinePLUS

    ... of Internal Medicine Summaries for Patients Screening for Prostate Cancer: A Guidance Statement From the Clinical Guidelines Committee ... Physicians The full report is titled “Screening for Prostate Cancer: A Guidance Statement From the Clinical Guidelines Committee ...

  6. Prostate Cancer: Chemotherapy

    MedlinePLUS

    ... Archives Sponsorship & Advertising Subscribe Free Fall UHe Highlights Prostate cancer is one of the most common cancers in ... In 2015, about 220,800 new cases of prostate cancer will be diagnosed and about 27,540 men ...

  7. Prostate Cancer Screening

    MedlinePLUS

    ... treat. There is no standard screening test for prostate cancer. Researchers are studying different tests to find those ... PSA level may be high if you have prostate cancer. It can also be high if you have ...

  8. Prostate cancer - resources

    MedlinePLUS

    Resources - prostate cancer ... The following organizations are good resources for information on prostate cancer : American Cancer Society -- www.cancer.org/cancer/prostatecancer/index National Cancer Institute -- www.cancer.gov/cancertopics/ ...

  9. Prostate Cancer: Diagnosis

    MedlinePLUS

    ... use the prostate specific antigen (PSA) test and digital rectal examination (DRE), to screen for prostate cancer. ... in your PSA score with your provider. DRE Digital Rectal Exam (DRE) NIH Medical Arts, National Cancer ...

  10. Prostate Cancer: Cryotherapy

    MedlinePLUS

    ... the prostate under the skin, guided by ultrasound. Argon gas creates an "ice ball" that kills cells ... to thaw passively or actively using helium or argon gas. If the prostate is longer than the ...

  11. Salvage High-intensity Focused Ultrasound for the Recurrent Prostate Cancer after Radiotherapy in Japan

    NASA Astrophysics Data System (ADS)

    Shoji, S.; Nakano, M.; Nagata, Y.; Uchida, T.

    2011-09-01

    To investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 20 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and June 1, 2010, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. The mean (range) age was 65 (52-80) years with a mean PSA level before radiation therapy of 26.6 (4.8-118) ng/mL. The mean (range) period after radiation therapy to HIFU was 41 (4-96) months. All men with presumed, organ-confined, recurrent disease following EBRT in 13 patients, brachytherapy in 5 patients (4 patients with high-dose brachytherapy with In192 and 1 with low-dose brachytherapy with Au98) or proton therapy in 4 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 21 months. Biochemical disease-free survival (bDFS) rates in patients with low-, intermediate- and high risk groups were 100%, 85.7%, and 18.2%, respectively. All nine patients who received a post HIFU prostate biopsy showed no malignancy. Side-effects included urethral stricture in 4 of the 22 patients (18%) and urinary incontinence in 4 of the 22 patients (18%). Recto-urethral fistula occurred in one patient (5%). Salvage HIFU is a minimally invasive for patients with low-and intermediate risk group with comparable morbidity to other forms of salvage treatment.

  12. Salvage high-intensity focused ultrasound for the recurrent prostate cancer after radiotherapy in Japan

    NASA Astrophysics Data System (ADS)

    Shoji, S.; Nakano, M.; Nagata, Y.; Uchida, T.

    2012-10-01

    Aim: to investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 22 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and April 1, 2010, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. The mean (range) age was 65 (52-80) years with a mean PSA level before radiation therapy of 14.3 (5.7-118) ng/mL. The mean (range) period after radiation therapy to HIFU was 36 (4-96) months. All men with presumed, organ-confined, recurrent disease following EBRT in 14 patients, brachytherapy in 5 patients (4 patients with high-dose brachytherapy with In192 and 1 with low-dose brachytherapy with Au98) or proton therapy in 3 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 24 months. Biochemical disease-free survival (bDFS) rates in patients with low-, intermediate-and high risk groups were 100%, 86%, and 14%, respectively. All nine patients who received a post HIFU prostate biopsy showed no malignancy. Side-effects included urethral stricture in 4 of the 25 patients (16%) and urinary incontinence in 4 of the 25 patients (16%). Recto-urethral fistula occurred in one patient (4%). Salvage HIFU is a minimally invasive for patients with low-and intermediate risk group with comparable morbidity to other forms of salvage treatment.

  13. SU-E-T-546: Use of Implant Volume for Quality Assurance of Low Dose Rate Brachytherapy Treatment Plans

    SciTech Connect

    Wilkinson, D; Kolar, M

    2014-06-01

    Purpose: To analyze the application of volume implant (V100) data as a method for a global check of low dose rate (LDR) brachytherapy plans. Methods: Treatment plans for 335 consecutive patients undergoing permanent seed implants for prostate cancer and for 113 patients treated with plaque therapy for ocular melanoma were analyzed. Plaques used were 54 COMS (10 to 20 mm, notched and regular) and 59 Eye Physics EP917s with variable loading. Plots of treatment time x implanted activity per unit dose versus v100 ^.667 were made. V100 values were obtained using dose volume histograms calculated by the treatment planning systems (Variseed 8.02 and Plaque Simulator 5.4). Four different physicists were involved in planning the prostate seed cases; two physicists for the eye plaques. Results: Since the time and dose for the prostate cases did not vary, a plot of implanted activity vs V100 ^.667 was made. A linear fit with no intercept had an r{sup 2} = 0.978; more than 94% of the actual activities fell within 5% of the activities calculated from the linear fit. The greatest deviations were in cases where the implant volumes were large (> 100 cc). Both COMS and EP917 plaque linear fits were good (r{sup 2} = .967 and .957); the largest deviations were seen for large volumes. Conclusions: The method outlined here is effective for checking planning consistency and quality assurance of two types of LDR brachytherapy treatment plans (temporary and permanent). A spreadsheet for the calculations enables a quick check of the plan in situations were time is short (e.g. OR-based prostate planning)

  14. Focal Therapy, Differential Therapy, and Radiation Treatment for Prostate Cancer

    PubMed Central

    Jain, Anudh K.; Ennis, Ronald D.

    2012-01-01

    Focal and differential therapy represent an approach to improve the therapeutic ratio of prostate cancer treatments. This concept is a shift from treating the whole gland to intensely treating the portion of the gland that contains significant tumor. However, there are many challenges in the move towards focal approaches. Defining which patients are suitable candidates for focal therapy approaches is an area of significant controversy, and it is likely that additional data from imaging or detailed biopsy methods is needed in addition to traditional risk factors. A number of methods have been suggested, and imaging with multiparametric MRI and transperineal template mapping biopsy have shown promise. The approach of differential therapy where the entire prostate is treated to a lower intensity and the tumor areas to high intensity is also discussed in detail. Radiation therapy is a well suited modality for the delivery of differential therapy. Data in the literature using external beam radiation, high dose rate brachytherapy, and low-dose rate brachytherapy for differential therapy are reviewed. Preliminary results are encouraging, and larger studies and randomized controlled trials are needed to validate this approach. PMID:22666239

  15. Dosimetric study of a brachytherapy treatment of esophagus with Brazilian 192Ir sources using an anthropomorphic phantom

    NASA Astrophysics Data System (ADS)

    Neves, Lucio P.; Santos, William S.; Gorski, Ronan; Perini, Ana P.; Maia, Ana F.; Caldas, Linda V. E.; Orengo, Gilberto

    2014-11-01

    Several radioisotopes are produced at Instituto de Pesquisas Energéticas e Nucleares for the use in medical treatments, including the activation of 192Ir sources. These sources are suitable for brachytherapy treatments, due to their low or high activity, depending on the concentration of 192Ir, easiness to manufacture, small size, stable daughter products and the possibility of re-utilization. They may be used for the treatment of prostate, cervix, head and neck, skin, breast, gallbladder, uterus, vagina, lung, rectum, and eye cancer treatment. In this work, the use of some 192Ir sources was studied for the treatment of esophagus cancer, especially the dose determination of important structures, such as those on the mediastinum. This was carried out utilizing a FASH anthropomorphic phantom and the MCNP5 Monte Carlo code to transport the radiation through matter. It was possible to observe that the doses at lungs, breast, esophagus, thyroid and heart were the highest, which was expected due to their proximity to the source. Therefore, the data are useful to assess the representative dose specific to brachytherapy treatments on the esophagus for radiation protection purposes. The use of brachytherapy sources was studied for the treatment of esophagus cancer. FASH anthropomorphic phantom and MCNP5 Monte Carlo code were employed. The doses at lungs, breast, esophagus, thyroid and heart were the highest. The data is useful to assess the representative doses of treatments on the esophagus.

  16. The Adjoint Method for The Optimization of Brachytherapy and Radiotherapy Patient Treatment Planning Procedures Using Monte Carlo Calculations

    SciTech Connect

    D.L. Henderson; S. Yoo; M. Kowalok; T.R. Mackie; B.R. Thomadsen

    2001-10-30

    The goal of this project is to investigate the use of the adjoint method, commonly used in the reactor physics community, for the optimization of radiation therapy patient treatment plans. Two different types of radiation therapy are being examined, interstitial brachytherapy and radiotherapy. In brachytherapy radioactive sources are surgically implanted within the diseased organ such as the prostate to treat the cancerous tissue. With radiotherapy, the x-ray source is usually located at a distance of about 1-metere from the patient and focused on the treatment area. For brachytherapy the optimization phase of the treatment plan consists of determining the optimal placement of the radioactive sources, which delivers the prescribed dose to the disease tissue while simultaneously sparing (reducing) the dose to sensitive tissue and organs. For external beam radiation therapy the optimization phase of the treatment plan consists of determining the optimal direction and intensity of beam, which provides complete coverage of the tumor region with the prescribed dose while simultaneously avoiding sensitive tissue areas. For both therapy methods, the optimal treatment plan is one in which the diseased tissue has been treated with the prescribed dose and dose to the sensitive tissue and organs has been kept to a minimum.

  17. A new optimization method using a compressed sensing inspired solver for real-time LDR-brachytherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Guthier, C.; Aschenbrenner, K. P.; Buergy, D.; Ehmann, M.; Wenz, F.; Hesser, J. W.

    2015-03-01

    This work discusses a novel strategy for inverse planning in low dose rate brachytherapy. It applies the idea of compressed sensing to the problem of inverse treatment planning and a new solver for this formulation is developed. An inverse planning algorithm was developed incorporating brachytherapy dose calculation methods as recommended by AAPM TG-43. For optimization of the functional a new variant of a matching pursuit type solver is presented. The results are compared with current state-of-the-art inverse treatment planning algorithms by means of real prostate cancer patient data. The novel strategy outperforms the best state-of-the-art methods in speed, while achieving comparable quality. It is able to find solutions with comparable values for the objective function and it achieves these results within a few microseconds, being up to 542 times faster than competing state-of-the-art strategies, allowing real-time treatment planning. The sparse solution of inverse brachytherapy planning achieved with methods from compressed sensing is a new paradigm for optimization in medical physics. Through the sparsity of required needles and seeds identified by this method, the cost of intervention may be reduced.

  18. Prostate Cancer Foundation

    MedlinePLUS

    ... as we Grow, Give and MOVE to raise awareness and critical funds for prostate cancer research. 10.01.2015 Foundation News 6 New ... 20 th Annual Home Run Challenge to Raise Awareness and Fund Research for Prostate Cancer 06.18.2015 Foundation News Prostate Cancer Foundation ...

  19. Prostate Cancer Jonathan Hagopian

    E-print Network

    Gleeson, Joseph G.

    Prostate Cancer Jonathan Hagopian Histology Self-Study Presentation HHMI Med-Into-Grad Program Fall 2007 #12;Overview · The Prostate Gland · Non-Malignant Hyperplasia · Adenocarcinoma · Grading and Staging · Metastasis #12;The Prostate Gland #12;Non-Malignant Hyperplasia #12;Non-Malignant Hyperplasia

  20. PROSTATE CANCER EVIDENCE ACADEMY

    E-print Network

    Bushman, Frederic

    PROSTATE CANCER EVIDENCE ACADEMY CME/CNE-Certified Course The Inn at Penn 3600 Sansom Street:30 PM R E G I S T E R O N L I N E AT PENNCMEONLINE.COM/NODE/57378 #12;OVERVIEW The Prostate Cancer, and model programs that are proven effective or being studied to improve prostate cancer prevention, control

  1. TODAY MEN WITH PROSTATE CANCER HAVE LARGER PROSTATES

    E-print Network

    Morrell, Christopher H.

    TODAY MEN WITH PROSTATE CANCER HAVE LARGER PROSTATES MARK R. FENELEY, PATRICIA LANDIS, INPAKALA Objectives. To examine the relationship between prostate size and the method of cancer detection in men with organ-confined prostate cancer, and compare prostate size in men with and without cancer. Methods

  2. Greater Postimplant Swelling in Small-Volume Prostate Glands: Implications for Dosimetry, Treatment Planning, and Operating Room Technique

    SciTech Connect

    Chung, Eugene; Stenmark, Matthew H.; Evans, Cheryl; Narayana, Vrinda; McLaughlin, Patrick W.

    2012-04-01

    Purpose: Postimplant prostatic edema has been implicated in suboptimal permanent implants, and smaller prostates have been reported to have worse dosimetric coverage. In this study we compare the degree of postimplant edema between larger and smaller prostates and examine the effects of prostate size on the dose delivered to 90% of the prostate (D90). Methods and Materials: From September 2003 to February 2006, 105 hormone-naive patients underwent permanent prostate brachytherapy with {sup 125}I Rapid Strand (Oncura Inc., Arlington Heights, IL). All patients underwent pelvic magnetic resonance imaging (MRI) within 3 weeks before implant, transrectal ultrasound at the time of implant, and both computed tomography and MRI 2.5 to 3 weeks after implant. Prostates were divided into 5 subgroups based on preimplant MRI volumes: less than 25 mL, 25 to 35 mL, 35 to 45 mL, 45 to 55 mL, and greater than 55 mL. Prostate swelling was assessed by use of preimplant and postimplant MRI volumes. Postimplant dosimetry was determined by MRI and compared between the subgroups. Results: All prostates showed postimplant swelling on MRI when compared with preimplant MRI, with a mean increase of 31% {+-} 31% (p < 0.0001). The greatest swelling was noted in small prostates (volume less than 25 mL), with a mean increase of 70% {+-} 36%. The degree of swelling in the group with a volume less than 25 mL was significantly larger than the degree of swelling in all other prostate subgroups (p < 0.003). Transrectal ultrasound significantly overestimates the prostate volume when compared with MRI by a mean of 15% {+-} 25% (p = 0.0006) and is more pronounced for smaller prostates. Although prostates with volumes less than 25 mL did not have significantly worse D90 compared with larger prostates, they had the largest percent of suboptimal implants by the standard ratio of D90 divided by the prescription dose. Conclusions: Although small prostates have the greatest postimplant edema, planning ultrasound at the time of implant overestimates the volumes of smaller prostates to a greater degree than larger prostates, which may minimize the effects of edema on postimplant dosimetry.

  3. [Hereditary prostate cancer].

    PubMed

    Wolski, Zbigniew; Drewa, Tomasz; Olszewska-S?onina, Dorota; Cussenot, Olivier

    2004-06-01

    About 10% of the prostate cancer cases were recognized as familial or hereditary. Till now gene/genes responsible for hereditary prostate cancer are not identified. Hereditary prostate cancer case concerning 3 brothers in family of 6 siblings from first marriage and a grandson from second marriage was presented. Two brothers were treated radical prostatectomy because of confined disease. The third brother with spreading disease died after androgen blockade management. We did not find any linkage between chosen markers of PCaP region (Predisposing for Prostate Cancer) and prostate cancer occurrence in this family. PMID:15510898

  4. The Personal Patient Profile-Prostate, Decision Support for Men With Localized Prostate Cancer: A Multi-center Randomized Trial

    PubMed Central

    Berry, Donna L; Halpenny, Barbara; Hong, Fangxin; Wolpin, Seth; Lober, William B; Russell, Kenneth J; Ellis, William J; Govindarajulu, Usha; Bosco, Jaclyn; Davison, B Joyce; Bennett, Gerald; Terris, Martha K; Barsevick, Andrea; Lin, Daniel W; Yang, Claire C; Swanson, Greg

    2011-01-01

    OBJECTIVE The purpose of this trial was to compare usual patient education plus the Internet-based, Personal Patient Profile-Prostate, versus usual education alone, on conflict associated with decision making, plus explore time-to-treatment and treatment choice. METHODS A randomized, multi-center clinical trial was conducted with measures at baseline, one and six months. Men with newly diagnosed localized prostate cancer who sought consultation at urology, radiation oncology or multi-disciplinary clinics in four geographically-distinct American cities were recruited. Intervention group participants used the Personal Patient Profile-Prostate, a decision support system comprised of customized text and video coaching regarding potential outcomes, influential factors, and communication with care providers. The primary outcome, patient-reported decisional conflict, was evaluated over time using Generalized Estimating Equations to fit generalized linear models. Additional outcomes, time-to-treatment, treatment choice and program acceptability/usefulness, were explored. RESULTS A total of 494 eligible men were randomized (266 intervention; 228 control). The intervention reduced adjusted decisional conflict over time as compared with the control group, for the uncertainty score (estimate ?3.61; (confidence interval, ?7.01,?0.22) and values clarity (estimate ?3.57; confidence interval (?5.85,?1.30) Borderline effect was seen for the total decisional conflict score (estimate ?1.75; confidence interval (?3.61,0.11). Time-to-treatment was comparable between groups, while undecided men in the intervention group chose brachytherapy more often than in the control group. Acceptability and usefulness were highly rated. CONCLUSION The Personal Patient Profile-Prostate is the first intervention to significantly reduce decisional conflict in a multi-center trial of American men with newly diagnosed localized prostate cancer. Our findings support efficacy of P3P for addressing decision uncertainty and facilitating patient selection of a prostate cancer treatment that is consistent with the patient values and preferences. PMID:22153756

  5. A novel curvilinear approach for prostate seed implantation

    SciTech Connect

    Podder, Tarun K.; Dicker, Adam P.; Hutapea, Parsaoran; Darvish, Kurosh; Yu Yan

    2012-04-15

    Purpose: A new technique called ''curvilinear approach'' for prostate seed implantation has been proposed. The purpose of this study is to evaluate the dosimetric benefit of curvilinear distribution of seeds for low-dose-rate (LDR) prostate brachytherapy. Methods: Twenty LDR prostate brachytherapy cases planned intraoperatively with VariSeed planning system and I-125 seeds were randomly selected as reference rectilinear cases. All the cases were replanned by using curved-needle approach keeping the same individual source strength and the volume receiving 100% of prescribed dose 145 Gy (V{sub 100}). Parameters such as number of needles, seeds, and the dose coverage of the prostate (D{sub 90}, V{sub 150}, V{sub 200}), urethra (D{sub 30}, D{sub 10}) and rectum (D{sub 5}, V{sub 100}) were compared for the rectilinear and the curvilinear methods. Statistical significance was assessed using two-tailed student's t-test. Results: Reduction of the required number of needles and seeds in curvilinear method were 30.5% (p < 0.001) and 11.8% (p < 0.49), respectively. Dose to the urethra was reduced significantly; D{sub 30} reduced by 10.1% (p < 0.01) and D{sub 10} reduced by 9.9% (p < 0.02). Reduction in rectum dose D{sub 5} was 18.5% (p < 0.03) and V{sub 100} was also reduced from 0.93 cc in rectilinear to 0.21 cc in curvilinear (p < 0.001). Also the V{sub 150} and V{sub 200} coverage of prostate reduced by 18.8% (p < 0.01) and 33.9% (p < 0.001), respectively. Conclusions: Significant improvement in the relevant dosimetric parameters was observed in curvilinear needle approach. Prostate dose homogeneity (V{sub 150}, V{sub 200}) improved while urethral dose was reduced, which might potentially result in better treatment outcome. Reduction in rectal dose could potentially reduce rectal toxicity and complications. Reduction in number of needles would minimize edema and thereby could improve postimplant urinary incontinence. This study indicates that the curvilinear implantation approach is dosimetrically superior to conventional rectilinear implantation technique.

  6. Sequential Comparison of Seed Loss and Prostate Dosimetry of Stranded Seeds With Loose Seeds in {sup 125}I Permanent Implant for Low-Risk Prostate Cancer

    SciTech Connect

    Saibishkumar, Elantholi P.; Borg, Jette; Yeung, Ivan; Cummins-Holder, Cheryl; Landon, Angela; Crook, Juanita

    2009-01-01

    Purpose: To compare stranded seeds (SSs) with loose seeds (LSs) in terms of prostate edema, dosimetry, and seed loss after {sup 125}I brachytherapy. Methods and Materials: Two prospective cohorts of 20 men participated in an institutional review board-approved protocols to study postimplant prostate edema and its effect on dosimetry. The LS cohort underwent brachytherapy between September 2002 and July 2003 and the SS cohort between April 2006 and January 2007. Both cohorts were evaluated sequentially using computed tomography-magnetic resonance imaging fusion-based dosimetry on Days 0, 7, and 30. No hormonal therapy or supplemental beam radiotherapy was used. Results: Prostate edema was less in the SS cohort at all points (p = NS). On Day 0, all the prostate dosimetric factors were greater in the LS group than in the SS group (p = 0.003). However, by Days 7 and 30, the dosimetry was similar between the two cohorts. No seeds migrated to the lung in the SS cohort compared with a total of five seeds in 4 patients in the LS cohort. However, the overall seed loss was greater in the SS cohort (24 seeds in 6 patients; 1.1% of total vs. 0.6% for LSs), with most seeds lost through urine (22 seeds in 5 patients). Conclusion: Despite elimination of venous seed migration, greater seed loss was observed with SSs compared with LSs, with the primary site of loss being the urinary tract. Modification of the technique might be necessary to minimize this. Prostate dosimetry on Days 7 and 30 was similar between the SS and LS cohorts.

  7. 6 Common Cancers - Prostate Cancer

    MedlinePLUS

    ... Bar Home Current Issue Past Issues 6 Common Cancers - Prostate Cancer Past Issues / Spring 2007 Table of Contents For ... early screening. Photo: AP Photo/Danny Moloshok Prostate Cancer The prostate gland is a walnut-sized structure ...

  8. Prostate cancer staging and grading

    MedlinePLUS

    ... to how fast your cancer may spread. For prostate cancer, the Gleason score is used. The term "stage" ... the prostate: Scores 2 through 5: Low-grade prostate cancer. Scores 6 through 7: Intermediate- (or in the ...

  9. Vaccine Treatment for Prostate Cancer

    MedlinePLUS

    ... Preventing and treating prostate cancer spread to bones Vaccine treatment for prostate cancer Sipuleucel-T (Provenge ® ) is ... less advanced prostate cancer. Possible side effects of vaccine treatment Side effects from the vaccine tend to ...

  10. Risks of Prostate Cancer Screening

    MedlinePLUS

    ... prostate. The prostate is a gland in the male reproductive system located just below the bladder (the organ that ... up part of semen . Enlarge Anatomy of the male reproductive and urinary systems, showing the prostate, testicles, bladder, and other organs. ...

  11. Relationship between isotope half-life and prostatic edema for optimal prostate dose coverage in permanent seed implants

    SciTech Connect

    Villeneuve, Maxime; Leclerc, Ghyslain; Lessard, Etienne; Pouliot, Jean; Beaulieu, Luc

    2008-05-15

    The robustness of treatment planning to prostatic edema for three different isotopes ({sup 125}I, {sup 103}Pd, and {sup 131}Cs) is explored using dynamical dose calculations on 25 different clinical prostate cases. The treatment plans were made using the inverse planning by simulated annealing (IPSA) algorithm. The prescription was 144, 127, and 125 Gy for {sup 125}I, {sup 131}Cs, and {sup 103}Pd, respectively. For each isotope, three dose distribution schemes were used to impose different protection levels to the urethra: V{sub 120}=0%, V{sub 150}=0%, and V{sub 150}=30%. Eleven initial edema values were considered ranging from 1.0 (no edema) to 2.0 (100%). The edema was assumed to resolve exponentially with time. The prostate volume, seed positions, and seed activity were dynamically tracked to produce the final dose distribution. Edema decay half-lives of 10, 30, and 50 days were used. A total of 675 dynamical calculations were performed for each initial edema value. For the {sup 125}I isotope, limiting the urethra V{sub 120} to 0% leads to a prostate D{sub 90} under 140 Gy for initial edema values above 1.5. Planning with urethra V{sub 150} at 0% provides a good response to the edema; the prostate D{sub 90} remains higher than 140 Gy for edema values up to 1.8 and a half-life of 30 days or less. For {sup 103}Pd, the prostate D{sub 90} is under 97% of the prescription dose for approximately 66%, 40%, and 30% of edema values for urethra V{sub 120}=0%, V{sub 150}=0%, and V{sub 150}=30%, respectively. Similar behavior is seen for {sup 131}Cs and the center of the prostate becomes 'cold' for almost all edema scenarios. The magnitude of the edema following prostate brachytherapy, as well as the half-life of the isotope used and that of the edema resorption, all have important impacts on the dose distribution. The {sup 125}I isotope with its longer half-life is more robust to prostatic edema. Setting up good planning objectives can provide an adequate compromise between organ doses and robustness. This is even more important since seed misplacements will contribute to further degrade dose coverage.

  12. Poster — Thur Eve — 77: Implanted Brachythearpy 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

    2014-08-15

    The study investigated the movement of implanted brachytherapy seeds upon transrectal US probe removal, providing insight into the underlying prostate deformation and an estimate of the impact on prostate dosimetry. Implanted seed distributions, one obtained with the prostate under probe compression and another with the probe removed, were reconstructed using C-arm fluoroscopy imaging. The prostate, delineated on ultrasound images, was registered to the fluoroscopy images using seeds and needle tracks identified on ultrasound. A deformation tensor and shearing model was developed to correlate probe-induced seed movement with position. Changes in prostate TG-43 dosimetry were calculated. The model was used to infer the underlying prostate deformation and to estimate the location of the prostate surface in the absence of probe compression. Seed movement patterns upon probe removal reflected elastic decompression, lateral shearing, and rectal bending. Elastic decompression was characterized by expansion in the anterior-posterior direction and contraction in the superior-inferior and lateral directions. Lateral shearing resulted in large anterior movement for extra-prostatic seeds in the lateral peripheral region. Whole prostate D90 increased up to 8 Gy, mainly due to the small but systematic seed movement associated with elastic decompression. For selected patients, lateral shearing movement increased prostate D90 by 4 Gy, due to increased dose coverage in the anterior-lateral region at the expense of the posterior-lateral region. The effect of shearing movement on whole prostate D90 was small compared to elastic decompression due to the subset of peripheral seeds involved, but is expected to have greater consequences for local dose coverage.

  13. Prostate Cancer Screening.

    PubMed

    Mulhem, Elie; Fulbright, Nikolaus; Duncan, Norah

    2015-10-15

    Among American men, prostate cancer is the most commonly diagnosed cancer and the second leading cause of cancer-related death. Although prostate-specific antigen (PSA) testing has been used to screen for prostate cancer for more than 25 years, the test has low sensitivity and specificity, and there is no clear evidence for determining what threshold warrants prostate biopsy. Only one of five randomized controlled trials of PSA screening showed an effect on prostate cancer-specific mortality, and the absolute reduction in deaths from prostate cancer was one per 781 men screened after 13 years of follow-up. None of the trials showed benefit in all-cause mortality, and screening increased prostate cancer diagnoses by about 60%. Harms of screening include adverse effects from prostate biopsy, overdiagnosis and overtreatment, and anxiety. One-half of screen-detected prostate cancers will not cause symptoms in the patient's lifetime, and 80% to 85% of men who choose observation will not die from prostate cancer within 15 years. Adverse effects of radical prostatectomy include perioperative complications, erectile dysfunction, and urinary incontinence. Radiation therapy can cause acute toxicity leading to urinary urgency, dysuria, diarrhea, and rectal pain; late toxicity includes erectile dysfunction, rectal bleeding, and urethral stricture. Despite variations across guidelines, no organization recommends routine PSA testing, and all endorse some form of shared decision-making before testing. If screening is performed, it should generally be discontinued at 70 years of age. PMID:26554408

  14. Case-Matched comparison of contemporary radiation therapy to surgery in patients with locally advanced prostate cancer

    SciTech Connect

    Fletcher, Sophie G.; Mills, Stacey E.; Smolkin, Mark E.; Theodorescu, Dan . E-mail: dt9d@virginia.edu

    2006-11-15

    Purpose: Few studies critically compare current radiotherapy techniques to surgery for patients with locally advanced prostate cancer, despite an urgent need to determine which approach offers superior cancer control. Our objective was to compare rates of biochemical relapse-free survival (BFS) and surrogates of disease specific survival among men with high risk adenocarcinoma of the prostate as a function of treatment modality. Methods and Materials: Retrospective data from 409 men with prostate-specific antigen (PSA) {>=}10 or Gleason 7-10 or Stage {>=}T2b cancer treated uniformly at one university between March 1988 and December 2000 were analyzed. Patients had undergone radical prostatectomy (RP), brachytherapy implant alone (BTM), or external beam radiotherapy with brachytherapy boost with short-term neoadjuvant and adjuvant androgen deprivation therapy (BTC). From the total study population a 1:1 matched-cohort analysis (208 patients matched via prostate-specific antigen, Gleason score) comparing RP with BTC was performed as well. Results: Estimated 4-year BFS rates were superior for patients treated with BTC (BTC 72%, BTM 25%, RP 53%; p < 0.001). Matched analysis of BTC vs. RP confirmed these results (BTC 73%, BTM 55%; p = 0.010). Relative risk (RR) of biochemical relapse for BTM and BTC compared with RP were 2.92 (1.95-4.36) and 0.56 (0.36-0.87) (p < 0.001, p = 0.010). RR for BTC from the matched cohort analysis was 0.44 (0.26-0.74; p = 0.002). Conclusions: High-risk prostate cancer patients receiving multimodality radiation therapy (BTC) display apparently superior BFS compared with those receiving surgery (RP) or brachytherapy alone (BTM)

  15. Modern head and neck brachytherapy: from radium towards intensity modulated interventional brachytherapy

    PubMed Central

    2014-01-01

    Intensity modulated brachytherapy (IMBT) is a modern development of classical interventional radiation therapy (brachytherapy), which allows the application of a high radiation dose sparing severe adverse events, thereby further improving the treatment outcome. Classical indications in head and neck (H&N) cancers are the face, the oral cavity, the naso- and oropharynx, the paranasal sinuses including base of skull, incomplete resections on important structures, and palliation. The application type can be curative, adjuvant or perioperative, as a boost to external beam radiation as well as without external beam radiation and with palliative intention. Due to the frequently used perioperative application method (intraoperative implantation of inactive applicators and postoperative performance of radiation), close interdisciplinary cooperation between surgical specialists (ENT-, dento-maxillary-facial-, neuro- and orbital surgeons), as well interventional radiotherapy (brachytherapy) experts are obligatory. Published results encourage the integration of IMBT into H&N therapy, thereby improving the prognosis and quality of life of patients. PMID:25834586

  16. Methods for routine calibration of brachytherapy sources.

    PubMed

    Williamson, J F; Khan, F M; Sharma, S C; Fullerton, G D

    1982-02-01

    Two types of routine geometry calibrators, the nuclear medicine dose calibrator and a Lucite jig holding a 30-ml external beam ion chamber with the source in a rigid geometry, were compared with open-air measurements for 137Cs, 192Ir, and 226Ra brachytherapy sources. The proximity of scattering surfaces in the second apparatus resulted in significant distortion of the buildup effect and deviation from the inverse square law (5% to 15%). For the dose calibrator, the response/Roentgen was found to be dependent not only on source energy, but on source capsule thickness as well. Approximately one half of the observed variation (27%) in calibration factors was accounted for by differences in filtration among sources. A mathematical logarithm that corrects for these geometric and filtration effects is presented. In addition, the activity assay procedure provided by the manufacturer of the dose calibrator is shown to be unsuitable for brachytherapy sources. Steps to overcome these problems are discussed. PMID:7054845

  17. The evolution of brachytherapy treatment planning

    SciTech Connect

    Rivard, Mark J.; Venselaar, Jack L. M.; Beaulieu, Luc

    2009-06-15

    Brachytherapy is a mature treatment modality that has benefited from technological advances. Treatment planning has advanced from simple lookup tables to complex, computer-based dose-calculation algorithms. The current approach is based on the AAPM TG-43 formalism with recent advances in acquiring single-source dose distributions. However, this formalism has clinically relevant limitations for calculating patient dose. Dose-calculation algorithms are being developed based on Monte Carlo methods, collapsed cone, and solving the linear Boltzmann transport equation. In addition to improved dose-calculation tools, planning systems and brachytherapy treatment planning will account for material heterogeneities, scatter conditions, radiobiology, and image guidance. The AAPM, ESTRO, and other professional societies are working to coordinate clinical integration of these advancements. This Vision 20/20 article provides insight into these endeavors.

  18. Living with Prostate Cancer

    MedlinePLUS

    ... cancer treatment and can improve many aspects of health, including muscle strength, balance, fatigue, cardiovascular fitness, and depression. Physical activity after a prostate cancer diagnosis is linked ...

  19. Screening for prostate cancer

    NASA Technical Reports Server (NTRS)

    Weirich, Stephen A.

    1993-01-01

    Despite recent advances in both the survival and cure rates for many forms of cancer, unfortunately the same has not been true for prostate cancer. In fact, the age-adjusted death rate from prostate cancer has not significantly improved since 1949, and prostate cancer remains the most common cancer in American men, causing the second highest cancer mortality rate. Topics discussed include the following: serum testosterone levels; diagnosis; mortality statistics; prostate-sppecific antigen (PSA) tests; and the Occupational Medicine Services policy at LeRC.

  20. Brachytherapy seed and applicator localization via iterative forward projection matching algorithm using digital X-ray projections

    NASA Astrophysics Data System (ADS)

    Pokhrel, Damodar

    Interstitial and intracavitary brachytherapy plays an essential role in management of several malignancies. However, the achievable accuracy of brachytherapy treatment for prostate and cervical cancer is limited due to the lack of intraoperative planning and adaptive replanning. A major problem in implementing TRUS-based intraoperative planning is an inability of TRUS to accurately localize individual seed poses (positions and orientations) relative to the prostate volume during or after the implantation. For the locally advanced cervical cancer patient, manual drawing of the source positions on orthogonal films can not localize the full 3D intracavitary brachytherapy (ICB) applicator geometry. A new iterative forward projection matching (IFPM) algorithm can explicitly localize each individual seed/applicator by iteratively matching computed projections of the post-implant patient with the measured projections. This thesis describes adaptation and implementation of a novel IFPM algorithm that addresses hitherto unsolved problems in localization of brachytherapy seeds and applicators. The prototype implementation of 3-parameter point-seed IFPM algorithm was experimentally validated using a set of a few cone-beam CT (CBCT) projections of both the phantom and post-implant patient's datasets. Geometric uncertainty due to gantry angle inaccuracy was incorporated. After this, IFPM algorithm was extended to 5-parameter elongated line-seed model which automatically reconstructs individual seed orientation as well as position. The accuracy of this algorithm was tested using both the synthetic-measured projections of clinically-realistic Model-6711 125I seed arrangements and measured projections of an in-house precision-machined prostate implant phantom that allows the orientations and locations of up to 100 seeds to be set to known values. The seed reconstruction error for simulation was less than 0.6 mm/3o. For the physical phantom experiments, IFPM absolute accuracy for position, polar angle, and azimuthal angel were (0.78+/-0.57) mm, (5.8+/-4.8)o, and (6.8+/-4.0)o, respectively. It avoids the need to match corresponding seeds in each projection and accommodates incomplete data, overlapping seed clusters, and highly-migrated seeds. IFPM was further generalized from 5-parameter to 6-parameter model which was needed to reconstruct 3D pose of arbitrary-shape applicators. The voxelized 3D model of the applicator was obtained from external complex combinatorial geometric modeling. It is then integrated into the forward projection matching method for computing the 2D projections of the 3D ICB applicators, iteratively. The applicator reconstruction error for simulation was about 0.5 mm/2 o. The residual 2D registration error (positional difference) between computed and actual measured applicator images was less than 1 mm for the intrauterine tandem and about 1.5 mm for the bilateral colpostats in each detector plane. By localizing the applicator's internal structure and the sources, the effect of intra and inter-applicator attenuation can be included in the resultant dose distribution and CBCT metal streaking artifact mitigation. The localization accuracy of better than 1 mm and 6o has the potential to support more accurate Monte Carlo-based or 2D TG-43 dose calculations in clinical practice. It is hoped the clinical implementation of IFPM approach to localize elongated line-seed/applicator for intraoperative brachytherapy planning may have a positive impact on the treatment of prostate and cervical cancers.

  1. Rotating-shield brachytherapy for cervical cancer

    NASA Astrophysics Data System (ADS)

    Yang, Wenjun; Kim, Yusung; Wu, Xiaodong; Song, Qi; Liu, Yunlong; Bhatia, Sudershan K.; Sun, Wenqing; Flynn, Ryan T.

    2013-06-01

    In this treatment planning study, the potential benefits of a rotating shield brachytherapy (RSBT) technique based on a partially-shielded electronic brachytherapy source were assessed for treating cervical cancer. Conventional intracavitary brachytherapy (ICBT), intracavitary plus supplementary interstitial (IS+ICBT), and RSBT treatment plans for azimuthal emission angles of 180° (RSBT-180) and 45° (RSBT-45) were generated for five patients. For each patient, high-risk clinical target volume (HR-CTV) equivalent dose in 2 Gy fractions (EQD2) (?/? = 10 Gy) was escalated until bladder, rectum, or sigmoid colon tolerance EQD2 values were reached. External beam radiotherapy dose (1.8 Gy × 25) was accounted for, and brachytherapy was assumed to have been delivered in 5 fractions. IS+ICBT provided a greater HR-CTV D90 (minimum EQD2 to the hottest 90%) than ICBT. D90 was greater for RSBT-45 than IS+ICBT for all five patients, and greater for RSBT-180 than IS+ICBT for two patients. When the RSBT-45/180 plan with the lowest HR-CTV D90 that was greater than the D90 the ICBT or IS+ICBT plan was selected, the average (range) of D90 increases for RSBT over ICBT and IS+ICBT were 16.2 (6.3-27.2)and 8.5 (0.03-20.16) Gy, respectively. The average (range) treatment time increase per fraction of RSBT was 34.56 (3.68-70.41) min over ICBT and 34.59 (3.57-70.13) min over IS+ICBT. RSBT can increase D90 over ICBT and IS+ICBT without compromising organ-at-risk sparing. The D90 and treatment time improvements from RSBT depend on the patient and shield emission angle.

  2. Physical and psychosocial side-effects of brachytherapy: a questionnaire survey

    PubMed Central

    Ferenc, Sara; Skowronek, Janusz; Karczewski, Jacek

    2015-01-01

    Purpose Brachytherapy (BT) plays an important role in cancer treatment. Like any other medical therapy it may, however, induce side effects whose recognition can affect the patient's quality of life. Therefore, the present study evaluated the frequency and severity of physical and psychosocial adverse effects of BT. Material and methods Patients (n = 70) undergoing high-dose-rate (HDR) BT or low-dose-rate (LDR) of head and neck, breast, and prostate cancers were interviewed face-to-face at the end of their course of treatment. Interviews concerned the occurrence of 35 physical (dermatological, gastroenterological, neurological, ocular, pulmonological, and urological) and 10 psychosocial side effects of BT. Results A high percentage of patients reported that BT decreased their life satisfaction (54.3%), sense of security (41.4%), and self-esteem (34.3%). The highest frequency of gastroenterological and urological symptoms was reported by prostate cancer patients. Cigarette smoking increased the frequency of nausea, dyschezia, and weight loss. Overweight patients were characterized by an increased rate of urinary incontinence and dyschezia, as well as more pronounced decrease of self-esteem and sense of security following BT treatment. Conclusions These findings are not only highly relevant to the way patients can be prepared for the therapy but also have a bearing on ways to minimize the number and severity of BT side effects. PMID:26622245

  3. Stereotactic body radiation therapy for prostate cancer: Rational and reasonable.

    PubMed

    Kupelian, Patrick; Mehta, Niraj H; King, Chris; Steinberg, Michael; Finkelstein, Steven E; Fernandez, Eduardo

    2015-01-01

    Stereotactic body radiation therapy (SBRT), a treatment procedure that uses large doses per fraction, is currently being used to treat prostate cancer with external radiation therapy in 4 to 5 treatments. Published series in the clinical use of SBRT in patients with localized prostate cancer demonstrate high efficacy within the available follow-up time periods. Rectal and sexual toxicity profiles have been favorable compared with other radiation techniques and surgery. Urinary toxicity profiles might be more comparable to those observed with brachytherapy, more pronounced in the acute setting. SBRT is technically more challenging, requiring precise geometric targeting with in-room image guidance. The use of large doses per fraction potentially provides unique biological effects on both tumor and normal tissues. Immunologic responses in normal tissues, local stromal microenvironment, and specific antigen-presenting cells induced by such high doses likely contribute to effective tumor kill. Ultimately, SBRT for prostate cancer offers significant logistical advantages, with increased convenience to patients and decreased overall cost to the health care delivery system. PMID:25413392

  4. Prostate Cancer Detection and Diagnosis: The Role of MR and its Comparison to other Diagnostic Modalities – A Radiologist's Perspective

    PubMed Central

    Penzkofer, Tobias; Tempany-Afdhal, Clare M.

    2013-01-01

    It is now universally recognized that many prostate cancers are over-diagnosed and over-treated. The European Randomized Study of Screening for Prostate Cancer (ERSPC) from 2009 evidenced that, to save one man from death of prostate cancer, over 1,400 men had to be screened, and 48 had to undergo treatment. Detection of prostate cancer is traditionally based upon digital rectal examination (DRE) and measuring serum prostate specific antigen (PSA), followed by ultrasound guided biopsy. The primary role of imaging for the detection and diagnosis of prostate cancer has been transrectal ultrasound (TRUS) guidance during biopsy. MRI has traditionally been used primarily for staging disease in men with biopsy proven cancer. It is has a well-established role in detecting T3 disease, planning radiation therapy, especially 3D conformal or intensity modulated external beam radiation therapy (IMRT), and planning and guiding interstitial seed implant or brachytherapy. New advances have now established prostate MRI can accurately characterize focal lesions within the gland, an ability that has led to new opportunities for improved cancer detection and guidance for biopsy. There are two new approaches to prostate biopsy are under investigation both use pre-biopsy MRI to define potential targets for sampling and then the biopsy is performed either with direct real-time MR guidance (in-bore) or MR fusion/registration with TRUS images (out-of-bore). In-bore or out-of-bore MRI-guided prostate biopsies have the advantage of using the MR target definition for accurate localization and sampling of targets or suspicious lesions. The out-of-bore method uses combined MRI/TRUS with fusion software that provided target localization and increases the sampling accuracy for TRUS-guided biopsies by integrating prostate MRI information with TRUS. Newer parameters for each imaging modality such as sonoelastography or shear wave elastography (SWE), contrast enhanced US (CEUS) and MRI-elastography, show promise to further enrich data sets. PMID:24000133

  5. Penile brachytherapy: Results for 49 patients

    SciTech Connect

    Crook, Juanita M. . E-mail: juanita.crook@rmp.uhn.on.ca; Jezioranski, John; Grimard, Laval; Esche, Bernd; Pond, G.

    2005-06-01

    Purpose: To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. Methods and Materials: From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Results: Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact and tumor-free penis at last follow-up or death. The actuarial penile preservation rate at 5 years was 86.5%. Conclusions: Brachytherapy is an effective treatment for T1, T2, and selected T3 SCC of the penis. Close follow-up is mandatory because local failures and many regional failures can be salvaged by surgery.

  6. Needle segmentation using 3D Hough transform in 3D TRUS guided prostate transperineal therapy

    SciTech Connect

    Qiu Wu; Yuchi Ming; Ding Mingyue; Tessier, David; Fenster, Aaron

    2013-04-15

    Purpose: Prostate adenocarcinoma is the most common noncutaneous malignancy in American men with over 200 000 new cases diagnosed each year. Prostate interventional therapy, such as cryotherapy and brachytherapy, is an effective treatment for prostate cancer. Its success relies on the correct needle implant position. This paper proposes a robust and efficient needle segmentation method, which acts as an aid to localize the needle in three-dimensional (3D) transrectal ultrasound (TRUS) guided prostate therapy. Methods: The procedure of locating the needle in a 3D TRUS image is a three-step process. First, the original 3D ultrasound image containing a needle is cropped; the cropped image is then converted to a binary format based on its histogram. Second, a 3D Hough transform based needle segmentation method is applied to the 3D binary image in order to locate the needle axis. The position of the needle endpoint is finally determined by an optimal threshold based analysis of the intensity probability distribution. The overall efficiency is improved through implementing a coarse-fine searching strategy. The proposed method was validated in tissue-mimicking agar phantoms, chicken breast phantoms, and 3D TRUS patient images from prostate brachytherapy and cryotherapy procedures by comparison to the manual segmentation. The robustness of the proposed approach was tested by means of varying parameters such as needle insertion angle, needle insertion length, binarization threshold level, and cropping size. Results: The validation results indicate that the proposed Hough transform based method is accurate and robust, with an achieved endpoint localization accuracy of 0.5 mm for agar phantom images, 0.7 mm for chicken breast phantom images, and 1 mm for in vivo patient cryotherapy and brachytherapy images. The mean execution time of needle segmentation algorithm was 2 s for a 3D TRUS image with size of 264 Multiplication-Sign 376 Multiplication-Sign 630 voxels. Conclusions: The proposed needle segmentation algorithm is accurate, robust, and suitable for 3D TRUS guided prostate transperineal therapy.

  7. PROSTATE AND ENDOCRINE DISRUPTION

    EPA Science Inventory

    This project offers the very distinct advantages of human relevance and enhanced susceptibility in the evaluation of environmental impacts on prostate development. The goal of this pilot project is to build a platform to evaluate the developmental origins of later life prostat...

  8. Prostate Surgery Codes

    Cancer.gov

    Prostate C619 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967, 9975-9992) Do not code an orchiectomy in this field. For prostate primaries, orchiectomies are coded in the data item “Hematologic Transplant and

  9. The Prostate Exam

    ERIC Educational Resources Information Center

    Romero, Frederico R.; Romero, Antonio W.; Filho, Thadeu Brenny; Kulysz, David; Oliveira, Fernando C., Jr.; Filho, Renato Tambara

    2012-01-01

    Objective: To help students, residents, and general practitioners to improve the technique, skills, and reproducibility of their prostate examination. Methods: We developed a comprehensive guideline outlining prostate anatomy, indications, patient preparation, positioning, technique, findings, and limitations of this ancient art of urological…

  10. Enlarged Prostate (BPH)

    MedlinePLUS

    ... too large, it can cause problems. An enlarged prostate is also called benign prostatic hyperplasia (BPH). Most men will get BPH as they get older. Symptoms often start after age 50. BPH is not cancer, and it does not seem to increase your ...

  11. [Prostate localization systems for prostate radiotherapy].

    PubMed

    de Crevoisier, R; Lagrange, J-L; Messai, T; M'Barek, B; Lefkopoulos, D

    2006-11-01

    The development of sophisticated conformal radiation therapy techniques for prostate cancer, such as intensity-modulated radiotherapy, implies precise and accurate targeting. Inter- and intrafraction prostate motion can be significant and should be characterized, unless the target volume may occasionally be missed. Indeed, bony landmark-based portal imaging does not provide the positional information for soft-tissue targets (prostate and seminal vesicles) or critical organs (rectum and bladder). In this article, we describe various prostate localization systems used before or during the fraction: rectal balloon, intraprostatic fiducials, ultrasound-based localization, integrated CT/linear accelerator system, megavoltage or kilovoltage cone-beam CT, Calypso 4D localization system tomotherapy, Cyberknife and Exactrac X-Ray 6D. The clinical benefit in using such prostate localization tools is not proven by randomized studies and the feasibility has just been established for some of these techniques. Nevertheless, these systems should improve local control by a more accurate delivery of an increased prescribed dose in a reduced planning target volume. PMID:17035061

  12. Epidemiology of Prostate Cancer.

    PubMed

    Bashir, Muhammad Naeem

    2015-01-01

    Prostate cancer is the most common malignancy among males worldwide, and is the second leading cause of cancer death among men in United States. According to GLOBOCAN (2012), an estimated 1.1 million new cases and 307,000 deaths were reported in 2012. The reasons for the increase of this disease are not known, but increasing life expectancy and modified diagnostic techniques have been suggested as causes. The established risk factors for this disease are advancing age, race, positive family history of prostate cancer and western diet (use of fat items). Several other risk factors, such as obesity, physical activity, sexual activity, smoking and occupation have been also associated with prostate cancer risk, but their roles in prostate cancer etiology remain uncertain. This mini-review aims to provide risk factors, disease knowledge, prevalence and awareness about prostate cancer. PMID:26225642

  13. Quality Assurance/Quality Control Issues for Intraoperative Planning and Adaptive Repeat Planning of Image-Guided Prostate Implants

    SciTech Connect

    Zaider, Marco Cohen, Gilad; Meli, Jerome; Rosenfeld, Anatoly B.

    2008-05-01

    The quality assurance/quality control purpose is this. We design a treatment plan, and we wish to be as certain as reasonably possible that the treatment is delivered as planned. In the case of conventionally planned prostate brachytherapy, implementing to the letter the implantation plan is rarely attainable and therefore can require adaptive replanning (a quality control issue). The reasons for this state of affairs include changes in the prostate shape and volume during implantation and treatment delivery (e.g., edema resolution) and unavoidable inaccuracy in the placement of the seeds in the prostate. As a result, quality-control activities (e.g., the need to monitor-ideally, on the fly-the target and urethral and rectal dosage) must be also addressed.

  14. Three-Dimensional Imaging in Gynecologic Brachytherapy: A Survey of the American Brachytherapy Society

    SciTech Connect

    Viswanathan, Akila N.; Erickson, Beth A.

    2010-01-15

    Purpose: To determine current practice patterns with regard to three-dimensional (3D) imaging for gynecologic brachytherapy among American Brachytherapy Society (ABS) members. Methods and Materials: Registered physician members of the ABS received a 19-item survey by e-mail in August 2007. This report excludes physicians not performing brachytherapy for cervical cancer. Results: Of the 256 surveys sent, we report results for 133 respondents who perform one or more implantations per year for locally advanced cervical cancer. Ultrasound aids 56% of physicians with applicator insertion. After insertion, 70% of physicians routinely obtain a computed tomography (CT) scan. The majority (55%) use CT rather than X-ray films (43%) or magnetic resonance imaging (MRI; 2%) for dose specification to the cervix. However, 76% prescribe to Point A alone instead of using a 3D-derived tumor volume (14%), both Point A and tumor volume (7%), or mg/h (3%). Those using 3D imaging routinely contour the bladder and rectum (94%), sigmoid (45%), small bowel (38%), and/or urethra (8%) and calculate normal tissue dose-volume histogram (DVH) analysis parameters including the D2cc (49%), D1cc (36%), D0.1cc (19%), and/or D5cc (19%). Respondents most commonly modify the treatment plan based on International Commission on Radiation Units bladder and/or rectal point dose values (53%) compared with DVH values (45%) or both (2%). Conclusions: More ABS physician members use CT postimplantation imaging than plain films for visualizing the gynecologic brachytherapy apparatus. However, the majority prescribe to Point A rather than using 3D image based dosimetry. Use of 3D image-based treatment planning for gynecologic brachytherapy has the potential for significant growth in the United States.

  15. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment

    NASA Astrophysics Data System (ADS)

    Miksys, N.; Xu, C.; Beaulieu, L.; Thomson, R. M.

    2015-08-01

    This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose calculation studies for various permanent implant brachytherapy treatments.

  16. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment.

    PubMed

    Miksys, N; Xu, C; Beaulieu, L; Thomson, R M

    2015-08-01

    This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose calculation studies for various permanent implant brachytherapy treatments. PMID:26216174

  17. Recent developments and best practice in brachytherapy treatment planning.

    PubMed

    Lee, C D

    2014-09-01

    Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation. PMID:24734939

  18. Recent developments and best practice in brachytherapy treatment planning

    PubMed Central

    2014-01-01

    Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation. PMID:24734939

  19. Optimization of prostate biopsy

    NASA Astrophysics Data System (ADS)

    Bauer, John J.; Zeng, Jianchao; Weir, James; Zhang, Wei; Sesterhenn, Isabell A.; Connelly, Roger R.; Moul, Judd W.; Mun, Seong K.

    1999-05-01

    Urologists routinely use the systematic sextant needle biopsy technique to detect prostate cancer. However, recent evidence suggests that this technique has a significant sampling error. We have developed a novel 3D computer assisted prostate biopsy simulator based upon 201 whole- mounted step-sectioned radical prostatectomy specimens to compare the diagnostic accuracy of various prostate needle biopsy protocols. Computerized prostate models have been developed to accurately depict the anatomy of the prostate and all individual tumor foci. We obtained 18-biopsies of each prostate model to determine the detection rates of various biopsy protocols. As a result, the 10- and 12- pattern biopsy protocols had a 99.0 percent detection rate, while the traditional sextant biopsy protocol rate was only 72.6 percent. The 5-region biopsy protocol had a 90.5 percent detection rate. the lateral sextant pattern revealed a detection rate of 95.5 percent, whereas the 4-pattern lateral biopsy protocol had a 93.5 percent detection rate. Our results suggest that all the biopsy protocols that use laterally placed biopsies based upon the five region anatomical model are superior to the routinely used sextant prostate biopsy pattern. Lateral biopsies in the mid and apical zones of the gland are the most important.

  20. Prostate cancer stem cells.

    PubMed

    Tu, Shi-Ming; Lin, Sue-Hwa

    2012-06-01

    Stem cells have long been implicated in prostate gland formation. The prostate undergoes regression after androgen deprivation and regeneration after testosterone replacement. Regenerative studies suggest that these cells are found in the proximal ducts and basal layer of the prostate. Many characteristics of prostate cancer indicate that it originates from stem cells. For example, the putative androgen receptor-negative (AR(-)) status of prostate stem cells renders them inherently insensitive to androgen blockade therapy. The androgen-regulated gene fusion TMPRSS2-ERG could be used to clarify both the cells of origin and the evolution of prostate cancer cells. In this review, we show that the hypothesis that distinct subtypes of cancer result from abnormalities within specific cell types-the stem cell theory of cancer-may instigate a major paradigm shift in cancer research and therapy. Ultimately, the stem cell theory of cancers will affect how we practice clinical oncology: our diagnosis, monitoring, and therapy of prostate and other cancers. PMID:22421313

  1. Canine prostatic carcinoma.

    PubMed

    Axiak, Sandra M; Bigio, Astrid

    2012-10-01

    Canine prostatic carcinoma is locally aggressive with a high rate of metastasis. Common metastatic sites include lymph nodes, lungs, liver, spleen, and bone. Staging relies on chest radiography, abdominal radiography, and abdominal ultrasonography, in addition to radiography of any painful regions. An enlarged, mineralized prostate is a frequent finding; in a castrated male dog, it is predictive of prostatic carcinoma. NSAIDs are an important component of treatment, although additional local and systemic therapies should be considered to improve the quality of life of these patients. PMID:23532757

  2. Radiation dose enhancement at tissue-tungsten interfaces in HDR brachytherapy.

    PubMed

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

    2014-11-01

    HDR BrachyView is a novel in-body dosimetric imaging system for real-time monitoring and verification of the source position in high dose rate (HDR) prostate brachytherapy treatment. It is based on a high-resolution pixelated detector array with a semi-cylindrical multi-pinhole tungsten collimator and is designed to fit inside a compact rectal probe, and is able to resolve the 3D position of the source with a maximum error of 1.5 mm. This paper presents an evaluation of the additional dose that will be delivered to the patient as a result of backscatter radiation from the collimator. Monte Carlo simulations of planar and cylindrical collimators embedded in a tissue-equivalent phantom were performed using Geant4, with an (192)Ir source placed at two different source-collimator distances. The planar configuration was replicated experimentally to validate the simulations, with a MOSkin dosimetry probe used to measure dose at three distances from the collimator. For the cylindrical collimator simulation, backscatter dose enhancement was calculated as a function of axial and azimuthal displacement, and dose distribution maps were generated at three distances from the collimator surface. Although significant backscatter dose enhancement was observed for both geometries immediately adjacent to the collimator, simulations and experiments indicate that backscatter dose is negligible at distances beyond 1 mm from the collimator. Since HDR BrachyView is enclosed within a 1 mm thick tissue-equivalent plastic shell, all backscatter radiation resulting from its use will therefore be absorbed before reaching the rectal wall or other tissues. dosimetry, brachytherapy, HDR. PMID:25325249

  3. Radiation dose enhancement at tissue-tungsten interfaces in HDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Han, Z.; Safavi-Naeini, M.; Alnaghy, S.; Cutajar, DL; Guatelli, S.; Petasecca, M.; Franklin, DR; Malaroda, A.; Carrara, M.; Bucci, J.; Zaider, M.; Lerch, MLF; Rosenfeld, AB

    2014-11-01

    HDR BrachyView is a novel in-body dosimetric imaging system for real-time monitoring and verification of the source position in high dose rate (HDR) prostate brachytherapy treatment. It is based on a high-resolution pixelated detector array with a semi-cylindrical multi-pinhole tungsten collimator and is designed to fit inside a compact rectal probe, and is able to resolve the 3D position of the source with a maximum error of 1.5 mm. This paper presents an evaluation of the additional dose that will be delivered to the patient as a result of backscatter radiation from the collimator. Monte Carlo simulations of planar and cylindrical collimators embedded in a tissue-equivalent phantom were performed using Geant4, with an 192Ir source placed at two different source-collimator distances. The planar configuration was replicated experimentally to validate the simulations, with a MOSkin dosimetry probe used to measure dose at three distances from the collimator. For the cylindrical collimator simulation, backscatter dose enhancement was calculated as a function of axial and azimuthal displacement, and dose distribution maps were generated at three distances from the collimator surface. Although significant backscatter dose enhancement was observed for both geometries immediately adjacent to the collimator, simulations and experiments indicate that backscatter dose is negligible at distances beyond 1 mm from the collimator. Since HDR BrachyView is enclosed within a 1 mm thick tissue-equivalent plastic shell, all backscatter radiation resulting from its use will therefore be absorbed before reaching the rectal wall or other tissues. dosimetry, brachytherapy, HDR

  4. Can Images Obtained With High Field Strength Magnetic Resonance Imaging Reduce Contouring Variability of the Prostate?

    SciTech Connect

    Usmani, Nawaid; Sloboda, Ron; Kamal, Wafa; Ghosh, Sunita; Pervez, Nadeem; Pedersen, John; Yee, Don; Danielson, Brita; Murtha, Albert; Amanie, John; Monajemi, Tara

    2011-07-01

    Purpose: The objective of this study is to determine whether there is less contouring variability of the prostate using higher-strength magnetic resonance images (MRI) compared with standard MRI and computed tomography (CT). Methods and Materials: Forty patients treated with prostate brachytherapy were accrued to a prospective study that included the acquisition of 1.5-T MR and CT images at specified time points. A subset of 10 patients had additional 3.0-T MR images acquired at the same time as their 1.5-T MR scans. Images from each of these patients were contoured by 5 radiation oncologists, with a random subset of patients repeated to quantify intraobserver contouring variability. To minimize bias in contouring the prostate, the image sets were placed in folders in a random order with all identifiers removed from the images. Results: Although there was less interobserver contouring variability in the overall prostate volumes in 1.5-T MRI compared with 3.0-T MRI (p < 0.01), there was no significant differences in contouring variability in the different regions of the prostate between 1.5-T MRI and 3.0-T MRI. MRI demonstrated significantly less interobserver contouring variability in both 1.5-T and 3.0-T compared with CT in overall prostate volumes (p < 0.01, p = 0.01), with the greatest benefits being appreciated in the base of the prostate. Overall, there was less intraobserver contouring variability than interobserver contouring variability for all of the measurements analyzed. Conclusions: Use of 3.0-T MRI does not demonstrate a significant improvement in contouring variability compared with 1.5-T MRI, although both magnetic strengths demonstrated less contouring variability compared with CT.

  5. A Prospective Study of Intrafraction Prostate Motion in the Prone vs. Supine Position

    SciTech Connect

    Wilder, Richard B.; Chittenden, Lucy; Mesa, Albert V.; Bunyapanasarn, Jane; Agustin, Jeff; Lizarde, Jessica; Ravera, John; Tokita, Kenneth M.

    2010-05-01

    Purpose: To prospectively analyze prostate intrafraction motion in the prone vs. supine position and to assess patient satisfaction with these two positions. Methods and Materials: Fifteen prostate cancer patients underwent implantation of five fiducial gold seeds in their prostate for localization. Patients were treated with high-dose-rate brachytherapy to 2,200 cGy followed by intensity-modulated radiation therapy (IMRT) to 5,040 cGy. Patients underwent computed tomography simulation and IMRT in the prone position. For the first five IMRT treatments, an electronic portal imaging system was used to acquire anteroposterior (AP) and lateral images pretreatment and posttreatment. We then repositioned each patient supine and repeated the process, resulting in 600 images. Results: Mean +- standard deviation intrafraction prostate motion was 2.1 +- 1.2 mm and 1.7 +- 1.4 mm (AP, p = 0.47), 2.2 +- 2.0 mm and 1.6 +- 1.8 mm (superoinferior, p = 0.16), and 1.0 +- 1.2 mm and 0.6 +- 0.9 mm (left-right, p = 0.03) in the prone and supine positions, respectively. Eighty percent of patients stated that they were more comfortable in the supine position (p = 0.02). Conclusions: Prone and supine positions resulted in a similar magnitude of AP and superoinferior intrafraction prostate motion (2 mm). Because there was no significant difference in the magnitude of AP and superoinferior prostate motion prone vs. supine and patients were more comfortable in the supine position, patients now undergo IMRT to the prostate and seminal vesicles at our center in the supine position.

  6. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    PubMed Central

    Fulkerson, Regina K.; Micka, John A.; DeWerd, Larry A.

    2014-01-01

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR) 192Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR 192Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and 192Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally, relative dose measurements of the surface dose distributions and characteristic depth dose curves were completed in-phantom. Results: Theoretical dose distributions and depth dose curves were generated for each applicator and agreed well with the measured values. A method of output verification was created that allows users to determine the applicator-specific dose to water at the treatment surface based on a measured air-kerma rate. Conclusions: The novel output verification methods described in this work will reduce uncertainties in dose delivery for treatments with these kinds of surface applicators, ultimately improving patient care. PMID:24506635

  7. A linear programming model for optimizing HDR brachytherapy dose distributions with respect to mean dose in the DVH-tail

    SciTech Connect

    Holm, Åsa; Larsson, Torbjörn; Tedgren, Åsa Carlsson

    2013-08-15

    Purpose: Recent research has shown that the optimization model hitherto used in high-dose-rate (HDR) brachytherapy corresponds weakly to the dosimetric indices used to evaluate the quality of a dose distribution. Although alternative models that explicitly include such dosimetric indices have been presented, the inclusion of the dosimetric indices explicitly yields intractable models. The purpose of this paper is to develop a model for optimizing dosimetric indices that is easier to solve than those proposed earlier.Methods: In this paper, the authors present an alternative approach for optimizing dose distributions for HDR brachytherapy where dosimetric indices are taken into account through surrogates based on the conditional value-at-risk concept. This yields a linear optimization model that is easy to solve, and has the advantage that the constraints are easy to interpret and modify to obtain satisfactory dose distributions.Results: The authors show by experimental comparisons, carried out retrospectively for a set of prostate cancer patients, that their proposed model corresponds well with constraining dosimetric indices. All modifications of the parameters in the authors' model yield the expected result. The dose distributions generated are also comparable to those generated by the standard model with respect to the dosimetric indices that are used for evaluating quality.Conclusions: The authors' new model is a viable surrogate to optimizing dosimetric indices and quickly and easily yields high quality dose distributions.

  8. NPIP: A skew line needle configuration optimization system for HDR brachytherapy

    SciTech Connect

    Siauw, Timmy; Cunha, Adam; Berenson, Dmitry; Atamtuerk, Alper; Hsu, I-Chow; Goldberg, Ken; Pouliot, Jean

    2012-07-15

    Purpose: In this study, the authors introduce skew line needle configurations for high dose rate (HDR) brachytherapy and needle planning by integer program (NPIP), a computational method for generating these configurations. NPIP generates needle configurations that are specific to the anatomy of the patient, avoid critical structures near the penile bulb and other healthy structures, and avoid needle collisions inside the body. Methods: NPIP consisted of three major components: a method for generating a set of cand