Hypofractionated external-beam radiation therapy (HEBRT) versus conventional external-beam radiation (CEBRT) in patients with localized prostate cancer: a systematic review and meta-analysis

Background: The purpose of this work was to conduct a systematic review and meta-analysis of all randomized controlled trials comparing the efficacy and side effect profile of hypofractionated versus conventional external-beam radiation therapy for prostate cancer. Methods: Several databases were searched, including Medline, EmBase, LiLACS, and Central. The endpoints were freedom from biochemical failure and side effects. We performed a metaanalysis of the published data. The results are expressed as the hazard ratio (HR) or risk ratio (RR), with the corresponding 95% confidence interval (CI). Results: The final analysis included nine trials comprising 2702 patients. Freedom from biochemical failure was reported in only three studies and was similar in patients who received hypofractionated or conventional radiotherapy (fixed effect, HR 1.03, 95% CI 0.88-1.20; P = 0.75), with heterogeneity [X-2 = 15.32, df = 2 (P = 0.0005); I-2 = 87%]. The incidence of acute adverse gastrointestinal events was higher in the hypofractionated group (fixed effect, RR 2.02, 95% CI 1.45-2.81; P < 0.0001). We also found moderate heterogeneity on this analysis [X (2) = 7.47, df = 5 (P = 0.19); I-2 = 33%]. Acute genitourinary toxicity was similar among the groups (fixed effect, RR 1.19, 95% CI 0.95-1.49; P = 0.13), with moderate heterogeneity [X-2 = 5.83, df = 4 (P = 0.21); I-2 = 31%]. The incidence of all late adverse events was the same in both groups (fixed effect, gastrointestinal toxicity, RR 1.17, 95% CI 0.79-1.72, P = 0.44; and acute genitourinary toxicity, RR 1.16, 95% CI 0.80-1.68, P = 0.44). Conclusion: Hypofractionated radiotherapy in localized prostate cancer was not superior to conventional radiotherapy and showed higher acute gastrointestinal toxicity in this meta-analysis. Because the number of published studies is still small, future assessments should be conducted to clarify better the true role of hypofractionated radiotherapy in patients with prostate cancer.