In an individual patient data meta-analysis reported at the 2026 ASCO Genitourinary Cancers Symposium (Abstract 305) and simultaneously published in The Lancet, Kishan et al found no apparent overall survival benefit of adding hormone therapy in patients undergoing postoperative radiotherapy after radical prostatectomy.
Study Details
The study included data from randomized phase III studies of postoperative radiotherapy with or without hormone therapy reported by December 2024, with meta-analyses performed to evaluate the effect of adding hormone therapy, short-term hormone therapy (4–6 months) or long-term hormone therapy (24 months) to postoperative radiotherapy. The primary outcome measure of the analysis was overall survival.
Key Findings
Individual patient data were available from six trials including a total of 6,057 patients. Median follow-up was 9.0 years (interquartile range = 7.2–10.7 years).
Overall, the addition of hormone therapy to radiotherapy did not significantly improve overall survival (hazard ratio [HR] = 0.87, 95% confidence interval [CI] = 0.76–1.01, P = .06); 10-year estimates were 84.3% vs 83.6%.
Among patients randomly assigned to treatment with vs without long-term hormone therapy, the HR for overall survival was 0.79 (95% CI = 0.63–1.00); among those randomly assigned to treatment with vs without short-term hormone therapy, the HR was 0.93 (95% CI = 0.77–1.11). However, no significant interaction between hormone therapy duration and treatment effect was observed (P for interaction = .17).
However, a significant interaction of hormone therapy treatment effect was observed among patients with a prostate-specific antigen (PSA) level of > 0.5 ng/mL vs 0.5 ng/mL or less (P for interaction = .02). Among all patients (all pre–postoperative radiotherapy PSA values), the upper bounds of the 95% CI of the HR for overall survival crossed 1.0 for patients randomly assigned to postoperative radiotherapy with vs without short-term hormone therapy (n = 3,938). Among patients randomly assigned to postoperative radiotherapy with vs without long-term hormone therapy (n = 1,088), the upper bounds of the 95% CI for overall survival HR were below 1.0 at PSA > 1.6 ng/mL.
The investigators concluded: “Our findings, we believe, provide the strongest level of evidence to date suggesting there might be no meaningful overall survival benefit to adding hormone therapy, either short-term or long-term hormone therapy, to postoperative radiotherapy for PSA 0.5 ng/mL or less, with no apparent difference in efficacy for short-term vs long-term hormone therapy. There is an unmet need to identify biomarkers to predict potential hormone therapy benefit.”
Amar U. Kishan, MD, of the Department of Radiation Oncology, University of California, Los Angeles, is the corresponding author for The Lancet article.
DISCLOSURE: The study was funded by the National Institutes of Health. For full disclosures of the study authors, visit thelancet.com.
