Hypofractionated Radiotherapy in Intermediate-Risk Prostate Cancer Patients: Long-Term Results.

Abstract

Background: To evaluate outcomes in terms of survival and toxicity in a series of intermediate-risk prostate cancer (PCa) patients treated with hypofractionated radiotherapy (HyRT) + hormonal therapy (HT) with or without image guidance (IGRT) and to investigate the impact of different variables. Methods: This is a multi-centric study. From January 2005 to December 2019, we treated 313 intermediate-risk PCa patients (T2b–T2c, Gleason score 7, or pre-treatment PSA 10 to 20 ng/mL) with HyRT. Patients received 54.75 Gy in 15 fractions in 5 weeks plus 9 months of neo-adjuvant, concomitant, and adjuvant HT with or without IGRT. Results: Median follow-up was 91.6 months (range 5.1–167.8 months). Median OS was not reached, and the 8- and 10-year OS was 81.9% and 72.4%, respectively. Median CSS was not reached, and the 8- and 10-year CSS was 97.9% and 94.5%, respectively. PSA at first follow-up <0.8 ng/mL was significantly related to better oncological outcomes (CSS, bRFS, LRFS, cPFS, and MFS) in both univariate and multivariate analysis. After Propensity Score matching, grade 2–3 acute and cumulative late GU (p = 0.153 and p = 0.581, respectively) and GI (p = 0.196 and p = 0.925, respectively) toxicity were not statistically different in patients treated with or without IGRT. Conclusions: HyRT is effective and safe regardless of the use of IGRT. PSA at first follow-up is an easily accessible prognostic factor that may help the clinicians to identify patients who require a treatment intensification.