Retrospective study of preoperative chemoradiotherapy with capecitabine versus capecitabine plus oxaliplatin for locally advanced rectal cancer

This study aimed to evaluate whether the addition of oxaliplatin to a neoadjuvant chemoradiotherapy (CRT) regimen could improve survival benefit in locally advanced rectal cancer (LARC) patients. We retrospectively analysed 73 LARC patients (cT2-4 and/or cN1-2) who received preoperative CRT with capecitabine followed by surgery (arm A, 43 patients) or capecitabine plus oxaliplatin followed by surgery (arm B, 30 patients). The main endpoints of the study were pathologic complete response (pCR) rate, overall survival (OS) and disease-free survival (DFS). The secondary endpoints included the sphincter preservation rate and safety. The pCR for arms A and B were 28% and 17% (P = 0.267). In arms A and B, the mean OS was 84.287 months (95% CI 68.413–100.160) and 106.333 months (95% CI 99.281–113.386) (P = 0.185); the mean DFS was 72.812 months (95% CI 56.271–89.353) and 95.073 months (95% CI 83.392–106.754) (P = 0.310); and the sphincter preservation rates were 72% and 67%, respectively (P = 0.619). The incidence of grade 3 toxicity was much higher in arm B than in arm A (57% vs. 21%, P = 0.002). Adding oxaliplatin to a preoperative CRT regimen for LARC did not improve the survival benefits of patients or increase toxicity.