Evaluation of biologic effective dose and schedule of fractionation for preoperative radiotherapy for rectal cancer: meta-analyses and meta-regression.

Purpose: To evaluate whether the risk of local recurrence depends on the biologic effective dose (BED) or fractionation dose in patients with resectable rectal cancer undergoing preoperative radiotherapy (RT) compared with surgery alone.

Methods And Materials: A meta-analysis of randomized controlled trials (RCTs) was performed. The MEDLINE, Embase, CancerLit, and Cochrane Library databases were systematically searched for evidence.