WHOLE PELVIC RADIOTHERAPY VERSUS PROSTATE ONLY RADIOTHERAPY IN THE MANAGEMENT OF LOCALLY ADVANCED OR AGGRESSIVE PROSTATE ADENOCARCINOMA

Purpose: To determine whether whole pelvic radiotherapy (WPRT) or prostate-only radiotherapy (PORT) yields improved biochemical disease-free survival (BDFS) in patients with advanced or aggressive prostate adenocarcinoma. Methods and Materials: Between 2000 and 2007, a consecutive sample of 277 patients with prostate adenocarcinoma and at least a 15 % likelihood of lymph node involvement who had undergone WPRT (n = 68) or PORT (n = 209) at two referral centers was analyzed. The median radiation dose in both arms was 75.6 Gy. The outcome measure was BDFS, as determined using the prostate-specific antigen nadir + 2 ng/mL definition of failure. BDFS was calculated using the Kaplan-Meier method and compared with the log-rank test. A multivariate analysis was performed to assess for confounding. Treatment-related toxicity was assessed using the National Cancer Institute's Common Terminology Criteria for Adverse Events guidelines. The median follow-up was 30 months. Results: WPRT patients had more advanced and aggressive disease at baseline (p < .001). The 4-year BDFS rate was 69.4 % in the PORT cohort and 86.3 % in the WPRT cohort (p = .02). Within the entire cohort, after adjustment for confounding variables, the pretreatment prostate-specific antigen (p < .001), Gleason score (p < .001),use of hormonal therapy (p = .002), and use of WPRT (vs. PORT, p = .006) predicted for BDFS. Patients undergoing WPRT had increased acute gastrointestinal toxicity (p = .048), but no significant difference in acute genitourinary toxicity was seen (p = .09). No difference in late toxicity was found. Conclusion: WPRT may yield improved BDFS in patients with advanced or aggressive prostate adenocarcinoma, but results in a greater incidence of acute toxicity. (C) 2009 Elsevier Inc.