Hypofractionated postoperative IMRT in prostate carcinoma: A phase I/II study

Aim: To report the outcome of hypofractionated radiotherapy after radical prostatectomy (RP) for prostate cancer (PCa) using simultaneous integrated boost-intensity modulated radiation therapy (SIB-IMRT). Patients and Methods: A total of 124 patients with PCa at high risk of relapse after RP or diagnosis of biochemical relapse were included. Patients received 62.5 Gy to the prostate bed and 45 Gy to pelvic nodes in 25 fractions. Androgen-suppressive therapy was prescribed based on National Comprehensive Cancer Network risk categories. Results: Median follow-up was 30 months. Only two patients (1.6%) developed grade 3 or more acute toxicity: one grade 3 skin toxicity (0.8%) and one grade 4 genitourinary toxicity (0.8%). Grade 2 acute gastrointestinal and genitourinary toxicity was recorded in 24.2% and 17.7% of patients, respectively. Five-year grade 2 or more gastrointestinal and genitourinary toxicity was 1.1% and 7.3%, respectively. Five-year biochemical relapse-free survival was 86.5%. Conclusion: After RP, hypofractionated IMRT-SIB demonstrated a favorable toxicity profile and encouraging results in terms of relapse-free survival.