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Background: Population-based studies demonstrate that Black men in the United States have an increased risk of death from prostate cancer. Determinants of racial disparities are multifactorial, including socioeconomic and biologic factors.Methods: The authors conducted a pooled analysis of patients derived from 152 centers within the Veterans Health Administration. The cohort included men who had nonmetastatic prostate diagnosed between 2001 and 2015 and received definitive radiation therapy. The primary endpoint was prostate cancer-specific mortality (PCSM). Secondary endpoints included all-cause mortality (ACM) and the time from a prostate-specific antigen level ≥4 ng/mL to biopsy and radiation therapy. A Cox regression model was performed to adjust for differences between clinical parameters.Results: Among the 31,131 patients included in the cohort, 9584 (30.8%) were Black. The 10-year cumulative incidence of death from prostate cancer was lower in Black men compared with White men (4.0% vs 4.8%; P = .004). In a competing risk model, Black race was associated with a decreased risk of PCSM (subdistribution hazard ratio, 0.79; 95% CI, 0.69-0.92; P = .002). Similarly, the 10-year cumulative incidence of death from any cause was lower in Black men (27.6% vs 31.8%; P < .001). In multivariable analysis, Black men had a 10% decreased risk of ACM (hazard ratio, 0.90; 95% CI, 0.85-0.95; P < .001).Conclusions: The current results indicate relatively lower PCSM and ACM among Black men who were included in a large Veterans Health Administration cohort and received radiation therapy as primary treatment for nonmetastatic prostate cancer. There is an ongoing need to continue to understand and mitigate the factors associated with disparities in health care outcomes. [ABSTRACT FROM AUTHOR]

Purpose: The survival benefit of combined radiation therapy (RT) and androgen deprivation therapy (ADT) compared with ADT alone for clinically lymph node-positive prostate cancer remains controversial.Methods and Materials: We identified patients with clinically node-positive, nonmetastatic prostate cancer diagnosed between 2000 and 2015 and treated with ADT (n = 450) or ADT-RT (n = 198) from a national Veterans Affairs database. We compared prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM) between treatment groups using multivariable competing-risks regression and Cox regression, respectively. An interaction term between ADT-RT and prostate-specific antigen (PSA) level (dichotomized about the median) was included in the multivariable models.Results: ADT-RT was associated with improved PCSM among patients with PSA levels less than the median of 26 ng/mL (sub-distribution hazard ratio, 0.50; 95% confidence interval [CI] 0.28-0.88; P = .02) but not greater than the median (hazard ratio [HR], 1.15; 95% CI 0.67-1.96; P = .62) (P = .038 for interaction). ADT-RT was also associated with improved ACM among patients with PSA levels less than the median (HR, 0.38; 95% CI 0.25-0.57; P < .001) but not greater than the median (HR, 0.91; 95% CI 0.60-1.38; P = .66) (P = .004 for interaction).Conclusions: Definitive treatment with ADT-RT is associated with improved PCSM and ACM among patients with clinically node-positive prostate cancer and lower baseline PSA levels. Patients with clinically node-positive disease appear to be a heterogeneous cohort, with a subset who may achieve long-term survival with combined RT and ADT. [ABSTRACT FROM AUTHOR]

We present a practical, generic, easy-to-use framework for the implementation of new radiation therapy technologies and treatment techniques in low-income countries. The framework is intended to standardize the implementation process, reduce the effort involved in generating an implementation strategy, and provide improved patient safety by reducing the likelihood that steps are missed during the implementation process. The 10 steps in the framework provide a practical approach to implementation. The steps are, 1) Site and resource assessment, 2) Evaluation of equipment and funding, 3) Establishing timelines, 4) Defining the treatment process, 5) Equipment commissioning, 6) Training and competency assessment, 7) Prospective risk analysis, 8) System testing, 9) External dosimetric audit and incident learning, and 10) Support and follow-up. For each step, practical advice for completing the step is provided, as well as links to helpful supplementary material. An associated checklist is provided that can be used to track progress through the steps in the framework. While the emphasis of this paper is on addressing the needs of low-income countries, the concepts also apply in high-income countries. [ABSTRACT FROM AUTHOR]

Purpose Modern radiotherapy (RT) protocols for prostate cancer often involve the use of narrow margins and image-based monitoring of rectum/bladder fill status. These protocols have allowed safe prostate dose escalation, maintaining acceptable levels for organs at risk (bladder and rectum). However, daily cone-beam CT (CBCT) image-guided RT has demonstrated considerable bladder volume variation throughout treatment, which suggests dose delivered may vary. By using CBCT-based parametrized 2D dose surface maps (DSM) of the inferior bladder, this study aims to evaluate bladder volume impact on bladder DSMs during high-precision RT for prostate cancer. Methods Seven prostate cancer patients treated using daily CBCT-based image-guided VMAT/IMRT were included in this study (81.0 Gy prescription dose). Planning CT and RT delivery adhered to a full bladder/empty rectum protocol, where daily CBCTs were used for patient realignment and to assess bladder/rectum filling status. Fourteen CBCTs per patient were rigidly registered to the planning CT using recorded treatment shifts, and the bladder was manually contoured on each CBCT. Contours were validated by the responsible radiation oncologist. For the planning CT and each CBCT, bladder wall dose was digitally projected onto 1024x1024 DSMs using orthographic ray-traced surface dose sampling. Bladder wall volumetric meshes were generated from contours using restricted Delaunay triangulation. Surface dose was sampled at ray-wall intersections, sub-pixel sampling was used to improve image quality, and rays were oriented parallel to the prostate-bladder center-of-mass connecting line. DSM dose distributions were compared between planned and delivered. Correlation with bladder volume variations was evaluated. Results Bladder volumes varied considerably during RT (15–42%), with slightly larger volumes at planning compared to treatment (p = 0.16). Differences at the central part of the DSM ranged between 1% and 7%. Overall, delivered doses were lower at the central part of the DSM compared to planned (range: −5.4 to 0.9 Gy). Plan-vs-delivery mean dose differences were slightly correlated with bladder volume differences (Rs = 0.55, p = 0.3). Conclusions No significant variations were observed in delivered doses at the interior part of the bladder although considerable bladder volume changes occurred during the RT course. The generally smaller treatment bladder volume possibly explains lower dose delivered to the inferior bladder sector. [ABSTRACT FROM AUTHOR]

Purpose: Cryotherapy is an option for the primary treatment of localized prostate cancer, along with radical prostatectomy, external beam radiation therapy, and brachytherapy. Although it is known that local recurrence can occur in >20% of patients treated with primary cryotherapy, unfortunately there is a paucity of data on later salvage treatments. The use of external beam radiation therapy is an attractive option after cryotherapy failure, but there is little data on its efficacy and toxicity. We evaluated the biochemical control and complication rates of salvage dose-escalated image guided intensity modulated radiation therapy (IG-IMRT) after cryotherapy failure., Methods and Materials: Patients who were treated at our institution from 2005 to 2016 were reviewed for those who underwent cryotherapy as initial treatment followed by salvage IGRT. Patients were treated with dose-escalated IG-IMRT using standard treatment margins of 3 mm posterior and 7 mm in all other directions and daily cone beam computed tomography or kv imaging to implanted fiducial markers. Biochemical progression was defined in accordance with the Phoenix consensus conference definition., Results: Eight patients were identified as having received post-cryotherapy salvage radiation within the study period. The median total dose was 77.7 Gy (range, 75.6-81.0 Gy). Median follow-up was 55 months (range, 6-88 months). Six patients remained biochemically controlled at the latest follow-up. One patient developed distant metastases after 22 months and one experienced biochemical failure at 30 months with no evidence of distant metastases. No patients experienced acute gastrointestinal toxicities of grade 2 or higher. There were no cases of late gastrointestinal or genitourinary toxicity., Conclusions: High-dose IG-IMRT results in high rates of salvage and extremely low rates of serious late toxicity for patients with locally recurrent prostate cancer after cryotherapy. Although the results are encouraging, given the small number of patients in this and other series, we remain cautious with regard to this treatment and believe the use of salvage radiation therapy after cryotherapy warrants further study.