GU Cancers Symposium 2011: ASCO ASTRO SUO - Initial report of RTOG 9601, a phase III trial in prostate cancer - Session Highlights


Effect of anti-androgen therapy (AAT) with bicalutamide during and after radiation therapy (RT) on freedom from progression and incidence of metastatic disease in patients following radical prostatectomy (RP) with pT2-3,N0 disease and elevated PSA levels

This study evaluated patients post radical prostatectomy with pT3N0 or pT2No and positive surgical margins and an elevated PSA. Freedom from progression and incidence of metastatic disease in these patients, following radical prostatectomy with an elevated PSA, was assessed. Patients were randomized to 150mg bicalutamide or placebo plus 64.8Gy RT. Patients were stratified by margin status, nadir PSA level, and entry PSA level. 771 patients were randomized and median age at entry was 65 years. PSA nadir after radical prostatectomy was <0.5ng/ml in 87% of patients, and PSA at entry was <1.6ng/ml in 87% of patients.

Median followup was 7.1 years and over 95% completed RT. 84% completed taking bicalutamide, compared with 95% completing oral placebo. The primary endpoint was overall survival. GU and GI toxicities were similar among the two study arms. Late gynecomastia occurred in 89% of bicalutamide treated patients. OS was 91% in the treated arm exceeding the 86% in the placebo arm. The FFP was 57% for bicalutamide vs. 40% in placebo. For Gleason scores ≤6, 7, and >8 the FFP for the bicalutamide and placebo arms were 63% vs. 50%, 55% vs. 39%, and 56% vs. 26%. This was beneficial in those with positive surgical margins and higher Gleason subtypes.

Presented by William U. Shipley, MD at the 2011 Genitourinary Cancers Symposium, General Session I: Emerging Trends in the Characterization and Treatment Decisions of Newly Diagnosed Prostate Cancer - February 17-19, 2011 - Orlando World Center Marriott, Orlando, Florida USA

The opinions expressed in this article are those of the Contributing Medical Editor and do not necessarily reflect the viewpoints of the GU Cancers Symposium