Top Line: Does short term ADT improve survival in the setting of dose escalated radiation for intermediate risk prostate cancer?
The Study: Today, many patients with IR prostate cancer are treated with dose escalated RT and short term ADT. However, the benefits of these two treatment approaches evolved somewhat independently from trials in the 1990’s. In addition, those trials included patients of various risk levels. RTOG 0815 was a large randomized trial designed to determine if the addition of short term ADT improved survival in men who received dose escalated RT. It included 1492 patients with stage cT2b-c, Gleason 7, or a PSA of 10-20. However, patients with all three of these IR factors and 50% or more of biopsy cores positive were ineligible. Most had Gleason 3+4 (67%) and PSA <10 (72%). Most patients were treated with EBRT (89%) to a dose of 79.2 Gy at 1.8 Gy per fraction while 10% received 45 Gy EBRT with a 110 Gy I-125 or 100 Gy Pd-103 LDR boost and 2% received a 21 Gy in 2 fractions HDR boost. They were randomized to receive 6 months of a LHRH agonist or antagonist plus an antiandrogen. At 8 years, the addition of ADT to RT did not significantly improve OS (84% v 79%). However, fewer patients died of prostate cancer (1 v 10), the cumulative incidence of DM was reduced from 4.3% to 1%, the rate of PSA failure was halved from 21% to 10%, and the rate of local recurrence was reduced from 3.9% to 2%. While no subset of patients had an OS benefit from ADT, every subset had improvement in other important clinical outcomes.
TBL: The addition of short term ADT to dose escalated radiation for intermediate risk prostate cancer doesn’t improve OS, but it reduces prostate cancer mortality, DM, and PSA failure. | Krauss, J Clin Oncol 2023
The Study: Today, many patients with IR prostate cancer are treated with dose escalated RT and short term ADT. However, the benefits of these two treatment approaches evolved somewhat independently from trials in the 1990’s. In addition, those trials included patients of various risk levels. RTOG 0815 was a large randomized trial designed to determine if the addition of short term ADT improved survival in men who received dose escalated RT. It included 1492 patients with stage cT2b-c, Gleason 7, or a PSA of 10-20. However, patients with all three of these IR factors and 50% or more of biopsy cores positive were ineligible. Most had Gleason 3+4 (67%) and PSA <10 (72%). Most patients were treated with EBRT (89%) to a dose of 79.2 Gy at 1.8 Gy per fraction while 10% received 45 Gy EBRT with a 110 Gy I-125 or 100 Gy Pd-103 LDR boost and 2% received a 21 Gy in 2 fractions HDR boost. They were randomized to receive 6 months of a LHRH agonist or antagonist plus an antiandrogen. At 8 years, the addition of ADT to RT did not significantly improve OS (84% v 79%). However, fewer patients died of prostate cancer (1 v 10), the cumulative incidence of DM was reduced from 4.3% to 1%, the rate of PSA failure was halved from 21% to 10%, and the rate of local recurrence was reduced from 3.9% to 2%. While no subset of patients had an OS benefit from ADT, every subset had improvement in other important clinical outcomes.
TBL: The addition of short term ADT to dose escalated radiation for intermediate risk prostate cancer doesn’t improve OS, but it reduces prostate cancer mortality, DM, and PSA failure. | Krauss, J Clin Oncol 2023