The Study: That’s why there’s now the STOPCAP meta-analysis to systematically put the pieces of the puzzle together. Granted “meta” might be an oversell, as a grand total of two trials met the inclusion criteria of results from a prospective randomization of prostate-directed radiation in the setting of upfront ADT and/or other systemic therapy for metastatic castrate-sensitive prostate cancer (mCSPC). That’s right, data was pooled from over 2100 men with mCSPC enrolled on HORRAD (n=432) and STAMPEDE (n=1694). As expected, across the board, there was no significant difference in overall survival or clinical (i.e., symptomatic or radiographic) progression. There was, however, an overall improvement in biochemical recurrence with the addition of radiation (HR 0.74). Also as hypothesized, among men with <5 bone mets across both trials, there was an overall survival improvement with the addition of radiation (HR 0.73).
Bottom Line: If you’re waiting for another more specific phase 3 trial to clear things up, you may be waiting a while—so in the meantime rest on the cumulative data demonstrating a significant advantage at 3 years in overall survival from 70% → 77% with the addition of upfront prostate radiation for men with mCSPC with <5 bone mets. | Burdett, Eur Urol 2019