High risk prostate cancer, particularly with high Gleason score (9-10) has high risk of distant metastasis and prostate cancer-related death. Due to inherent challenges in participant accrual, there are no prospective randomized trials comparing prostatectomy (RP), external beam radiotherapy with androgen deprivation (EBRT), and external beam radiotherapy with brachytherapy boost and androgen deprivation (EBRT+BT). The current study performed a multi-institutional consortium retrospective review of 1809 men across 12 institutions who underwent RP (n=639), EBRT(n=734), or EBRT+BT(n=436) in order to identify any prostate-cancer specific survival (PCSS) benefit using this larger dataset. EBRT+BT had a significantly lower PCSS than RP (HR=0.38) or EBRT (HR=0.41).

5-year PCSS was 12%, 13%, and 3% for RP, EBRT, and EBRT+BT respectively.

Distant metastasis rate was significantly lower with EBRT+BT as compared to RP (HR=0.27) or EBRT (HR=0.30). There was an overall survival benefit in the first 7.5 years of follow-up with EBRT+BT versus RP (HR=0.66) or EBRT (HR=0.61). Of note, 43% of patients undergoing RP required post-operative radiotherapy. This study presents novel findings to suggest both a distant metastasis and prostate-cancer specific survival benefit from EBRT+BT. Strengths of the study include large statistical power, generalizability, and robust statistical methods including propensity score matching. Limitations include those inherent to the retrospective study design. Overall, these are valuable and statistically powerful data suggesting that patients with Gleason score 9-10 prostate cancer should be treated with extremely dose-escalated radiotherapy, including external beam radiotherapy and brachytherapy boost along with androgen deprivation too optimize clinical outcomes.

PDF