The long and short of it.
Top Line: Does short-term ADT provide a long-term benefit when added to radiation in men with intermediate risk disease?
The Study: EORTC 22991 was an important randomized trial that supports the use of short-term ADT in men treated with radiation for intermediate risk prostate cancer. However, long-term outcomes are important for prostate cancer. The trial included both intermediate and high risk, and it allowed a dose as low as 70 Gy. Here we have long-term outcomes specifically for the group of men with intermediate risk disease who received at least 74 Gy (some received 78 Gy), which comprised 59% of the 819 men enrolled. They were randomized to radiation alone or 6 months of concurrent and adjuvant goserelin along with one month of bicalutamide. At 10 years, the addition of 6 months ADT significantly increased the rate of event-free survival (PSA relapse, clinical relapse, 2nd line tx, or death) from 49 → 68%. ADT also significantly increased the rate of 10-year clinical DFS (i.e. ignoring PSA relapse) from 66 → 76%, which appeared to be driven by a decrease in locoregional recurrence from 10 → 4%. There was no difference in the 10-year rates of overall (80% vs 74%) or DM-free survival (79% vs 73%) with or without ADT. So, did outcomes differ according to favorable vs unfavorable intermediate risk disease? Unfortunately, all the clinicopathologic data necessary for such re-classification wasn’t available.
TBL: In EORTC 22991, the addition of 6 months concurrent and adjuvant ADT to radiation improved event-free and clinical disease-free survival at 10 years mainly by reducing PSA and locoregional failure with no difference in DM or overall survival. | Bolla, J Clin Oncol 2021