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Purpose: Utilization of stereotactic body radiation therapy (SBRT) for treatment of localized prostate cancer is increasing. Guidelines and payers variably support the use of prostate SBRT. We therefore sought to systematically analyze biochemical recurrence-free survival (bRFS), physician-reported toxicity, and patient-reported outcomes after prostate SBRT.Methods and Materials: A systematic search leveraging Medline via PubMed and EMBASE for original articles published between January 1990 and January 2018 was performed. This was supplemented by abstracts with sufficient extractable data from January 2013 to March 2018. All prospective series assessing curative-intent prostate SBRT for localized prostate cancer reporting bRFS, physician-reported toxicity, and patient-reported quality of life with a minimum of 1-year follow-up were included. The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Meta-analyses were performed with random-effect modeling. Extent of heterogeneity between studies was determined by the I2 and Cochran's Q tests. Meta-regression was performed using Hartung-Knapp methods.Results: Thirty-eight unique prospective series were identified comprising 6116 patients. Median follow-up was 39 months across all patients (range, 12-115 months). Ninety-two percent, 78%, and 38% of studies included low, intermediate, and high-risk patients. Overall, 5- and 7-year bRFS rates were 95.3% (95% confidence interval [CI], 91.3%-97.5%) and 93.7% (95% CI, 91.4%-95.5%), respectively. Estimated late grade ≥3 genitourinary and gastrointestinal toxicity rates were 2.0% (95% CI, 1.4%-2.8%) and 1.1% (95% CI, 0.6%-2.0%), respectively. By 2 years post-SBRT, Expanded Prostate Cancer Index Composite urinary and bowel domain scores returned to baseline. Increasing dose of SBRT was associated with improved biochemical control (P = .018) but worse late grade ≥3 GU toxicity (P = .014).Conclusions: Prostate SBRT has substantial prospective evidence supporting its use, with favorable tumor control, patient-reported quality of life, and levels of toxicity demonstrated. SBRT has sufficient evidence to be supported as a standard treatment option for localized prostate cancer while ongoing trials assess its potential superiority. [ABSTRACT FROM AUTHOR]

Abstract Background Intermediate clinical endpoints (ICEs) prognostic for overall survival (OS) are needed for men receiving postprostatectomy radiation therapy (PORT) to improve clinical trial design. Objective To identify a potential ICE for men receiving PORT. Design, setting, and participants We performed an institutional review board–approved multi-institutional retrospective study of 566 men consecutively treated with PORT at tertiary care centers from 1986 to 2013. The median follow-up was 8.2 yr. Outcome measurements and statistical analysis Biochemical failure (BF), distant metastases (DM), and castrate-resistant prostate cancer (CRPC) were evaluated for correlation with OS and assessed as time-dependent variables in a multivariable Cox proportional hazards model and in landmark analyses at 1, 3, 5, and 7 yr after PORT. Cross-validated concordance (c) indices were used to assess model discrimination. Results and limitations OS at 1, 3, 5, and 7 yr after PORT was 98%, 95%, 90%, and 82%, respectively. In a time-varying model controlling for clinical and pathologic variables, BF (hazard ratio [HR] 2.32, 95% confidence interval [CI] 1.45–3.71; p < 0.001), DM (HR 6.52, 95% CI 4.20–10.1; p < 0.001), and CRPC (HR 2.47, 95% CI 1.56–3.92; p < 0.001) were associated with OS. In landmark analyses, 5-yr DM had the highest c index when adjusting for baseline covariates (0.78), with 5-yr DM also providing the greatest increase in discriminatory power over a model only including baseline covariates. These findings require validation in prospective randomized data. Conclusions While limited by the retrospective nature of the data, 5-yr DM is associated with lower OS following PORT, outperforming the prognostic capability of BF and CRPC at 1, 3, 5, or 7 yr after treatment. Confirmation of this ICE as a surrogate for OS is needed from randomized trial data so that it can be incorporated into future clinical trial design. Patient summary We assessed potential intermediate clinical endpoints prognostic for overall survival in a cohort of men receiving radiotherapy after prostatectomy. We identified the development of metastatic disease within 5 yr after treatment as the strongest predictor of overall survival. Take Home Message We assessed potential intermediate clinical endpoints prognostic for overall survival in a cohort of men receiving radiotherapy after prostatectomy. We identified the development of metastatic disease within 5 yr after treatment as the strongest predictor of overall survival. [ABSTRACT FROM AUTHOR]

Background Outcomes with postprostatectomy salvage radiation therapy (SRT) are not ideal. Little evidence exists regarding potential benefits of adding whole pelvic radiation therapy (WPRT) alone or in combination with androgen deprivation therapy (ADT). Objective To explore whether WPRT and/or ADT added to prostate bed radiation therapy (PBRT) improves freedom from biochemical failure (FFBF) or distant metastases (DM). Design, setting, and participants A database was compiled from 10 academic institutions of patients with postprostatectomy prostate-specific antigen (PSA) >0.01 ng/ml; pT1-4, Nx/0, cM0; and Gleason score (GS) ≥7 treated between 1987 and 2013. Median follow-up was 51 mo. Interventions WPRT and/or ADT in addition to PBRT. Outcome measurements and statistical analyses FFBF and DM were calculated using cumulative incidence estimation. Multivariable analysis (MVA) utilized cumulative incidence regression. Results and limitation Median pre-SRT PSA was 0.5 ng/ml for 1861 patients. Median follow-up for patients not experiencing biochemical failure (BF) was 55 mo. MVA showed increased BF for PBRT versus WPRT (hazard ratio [HR] 1.82, p < 0.001) and no ADT versus ADT (HR 1.70, p < 0.001). WPRT was associated with a 5-yr FFBF of 62% versus 49% ( p < 0.001) for PBRT. ADT use was associated with improved 5-yr FFBF (55% vs 50%, p = 0.012). No significant differences in DM cumulative incidence were found. Conclusions For patients with GS ≥7 receiving SRT, clinicians should weigh FFBF benefits of WPRT and ADT against toxicities. Future studies should explore the impact of WPRT on quality of life, clinical progression, and overall survival. Patient summary We evaluated patients with prostate cancer treated with radiation after surgery to remove the prostate. Both radiation to the pelvic lymph nodes and suppression of testosterone lowered the chance of increasing prostate-specific antigen (a marker for cancer returning). [ABSTRACT FROM AUTHOR]