Stereotactic body radiotherapy for prostate cancer: A preliminary report

Abstract

AIMS: We report the results of a retrospective study of stereotactic body radiotherapy (SBRT) using a Cyberknife for prostate cancer. METHODS: In all 29 patients were treated with hypofractionated SBRT using a Cyberknife at median 36 Gy in five fractions. All the patients were treated with a radical aim. Prostate-specific antigen (PSA) was evaluated at baseline and after radiotherapy. Acute (≤3 months) and late (>3 months) urinary and rectal toxicities were recorded according to the CTCAE version 4.0. RESULTS: The median duration of follow up was 41 months. PSA values decreased in a time-dependent way. The median PSA nadir was 0.329 ng/mL, achieved after a median of 23 months' follow up. Two patients had a PSA failure according to the definition of nadir + 2 ng/mL. Eight patients (28%) had a benign PSA bounce at median 9 months after radiotherapy. CTCAE Grade 2 and 3 late urinary toxicities were reported in 3 and 3%, respectively. One patient had exacerbated urinary symptoms and received an operation. There were no severe late rectal toxicities. CONCLUSIONS: The preliminary findings of our study suggest SBRT is feasible for prostate cancer treatment. Further studies with more patients and longer follow-up duration are required.