Hypofractionated radiotherapy with or without IGRT in prostate cancer: preliminary report of acute toxicity.

BACKGROUND To evaluate the acute tolerance to hypofractionated schedule of patients with prostate cancer. PATIENTS AND METHODS We treated 62 patients with intermediate risk prostate cancer. All patients were treated with a total dose of 43.8 Gy on seminal vesicles and 54.75 Gy on prostate, 3.65 Gy per fraction, three times a week for a total of 5 weeks. All patients underwent neoadjuvant, concomitant and adjuvant hormonal therapy. Thirty-six patients were submitted to image-guided radiation therapy (IGRT). RESULTS Median follow-up was 15 months (range 3-33 months). Toxicities during the treatment were: grade 1-2 gastrointestinal (GI) toxicity, 22.6%; grade 1-2 genitourinary (GU) toxicity, 51.6%. Toxicities 3 months after the end of the treatment were grade 1-2 GI 6.5%, grade 1-2 GU 9.7%. No statistical difference was observed comparing acute toxicity in patients treated with or without IGRT. CONCLUSION This study showed that the hypofractionation schedule used is well tolerated, with a low rate of acute grade 1-2 GI toxicity and without major grade (≥3) acute toxicity. Longer follow-up is needed to determine if this low rate of acute toxicity will be translated in a low rate of late toxicity.