Thaker N.G.,University of Houston |
Kudchadker R.J.,University of Houston |
Swanson D.A.,University of Houston |
Albert J.M.,Banner Health |
And 12 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2014
Purpose: To design and implement a unique training program that uses a phantombased simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education.Methods and Materials: Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 (125I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis.Results: Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 > 95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process.Conclusions: Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB. © 2014 Elsevier Inc.
Comparative analysis of prostate-specific antigen free survival outcomes for patients with low, intermediate and high risk prostate cancer treatment by radical therapy. Results from the Prostate Cancer Results Study Group
Billiet I.,Urology Center Kortrijk |
Bostwick D.,Bostwick Laboratories Inc. |
Dicker A.P.,Thomas Jefferson University |
Frank S.,Andersen Center |
And 19 more authors.
BJU International | Year: 2012
A large number of studies have been conducted on the primary therapy of prostate cancer but very few randomized controlled trials have been conducted. The comparison of outcomes from individual studies involving surgery (radical prostatectomy or robotic radical prostatectomy), external beam radiation (EBRT) (conformal, intensity modulated radiotherapy, protons), brachytherapy, cryotherapy or high intensity focused ultrasound remains problematic due to the non-uniformity of reporting results and the use of varied disease outcome endpoints. Technical advances in these treatments have also made long-term comparisons difficult. The Prostate Cancer Results Study Group was formed to evaluate the comparative effectiveness of prostate cancer treatments. This international group conducted a comprehensive literature review to identify all studies involving treatment of localized prostate cancer published during 2000-2010. Over 18 000 papers were identified and a further selection was made based on the following key criteria: minimum/median follow-up of 5 years; stratification into low-, intermediate- and high-risk groups; clinical and pathological staging; accepted standard definitions for prostate-specific antigen failure; minimum patient number of 100 in each risk group (50 for high-risk group). A statistical analysis (standard deviational ellipse) of the study outcomes suggested that, in terms of biochemical-free progression, brachytherapy provides superior outcome in patients with low-risk disease. For intermediate-risk disease, the combination of EBRT and brachytherapy appears equivalent to brachytherapy alone. For high-risk patients, combination therapies involving EBRT and brachytherapy plus or minus androgen deprivation therapy appear superior to more localized treatments such as seed implant alone, surgery alone or EBRT. It is anticipated that the study will assist physicians and patients in selecting treatment for men with newly diagnosed prostate cancer. © 2012 BJU INTERNATIONAL.
Nguyen P.L.,Harvard University |
Chen M.-H.,University of Connecticut |
Beckman J.A.,Harvard University |
Beard C.J.,Harvard University |
And 11 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2012
Purpose: It is unknown whether the excess risk of all-cause mortality (ACM) observed when androgen deprivation therapy (ADT) is added to radiation for men with prostate cancer and a history of congestive heart failure (CHF) or myocardial infarction (MI) also applies to those with high-risk disease. Methods and Materials: Of 14,594 men with cT1c-T3aN0M0 prostate cancer treated with brachytherapy-based radiation from 1991 through 2006, 1,378 (9.4%) with a history of CHF or MI comprised the study cohort. Of these, 22.6% received supplemental external beam radiation, and 42.9% received a median of 4 months of neoadjuvant ADT. Median age was 71.8 years. Median follow-up was 4.3 years. Cox multivariable analysis tested for an association between ADT use and ACM within risk groups, after adjusting for treatment factors, prognostic factors, and propensity score for ADT. Results: ADT was associated with significantly increased ACM (adjusted hazard ratio [AHR] = 1.76; 95% confidence interval [CI], 1.32-2.34; p = 0.0001), with 5-year estimates of 22.71% with ADT and 11.62% without ADT. The impact of ADT on ACM by risk group was as follows: high-risk AHR = 2.57; 95% CI, 1.17-5.67; p = 0.019; intermediate-risk AHR = 1.75; 95% CI, 1.13-2.73; p = 0.012; low-risk AHR = 1.52; 95% CI, 0.96-2.43; p = 0.075). Conclusions: Among patients with a history of CHF or MI treated with brachytherapy-based radiation, ADT was associated with increased all-cause mortality, even for patients with high-risk disease. Although ADT has been shown in Phase III studies to improve overall survival in high-risk disease, the small subgroup of high-risk patients with a history of CHF or MI, who represented about 9% of the patients, may be harmed by ADT. Copyright © 2012 Elsevier Inc. Printed in the USA. All rights reserved.
Nguyen P.L.,Dana-Farber Cancer Institute |
Nguyen P.L.,Harvard University |
Chen M.H.,University of Connecticut |
Choueiri T.K.,Dana-Farber Cancer Institute |
And 18 more authors.
International Journal of Radiation Oncology Biology Physics | Year: 2011
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. © 2011 Elsevier Inc.