Pre- and Postoperative Capecitabine Without or With Oxaliplatin in Locally Advanced Rectal Cancer: PETACC 6 Trial by EORTC GITCG and ROG, AIO, AGITG, BGDO, and FFCD

PURPOSE The PETACC 6 trial investigates whether the addition of oxaliplatin to preoperative capecitabine-based chemoradiation and postoperative capecitabine improves disease-free survival (DFS) in locally advanced rectal cancer. METHODS Between November 2008 September 2011, patients with adenocarcinoma within 12 cm from anal verge, T3/4 and/or node positive, were randomly assigned 5 weeks (45-50.4 Gy) followed by six cycles adjuvant capecitabine, both without (control arm, 1) or (experimental 2) oxaliplatin. primary end point was improvement 3-year DFS 65% 72% (hazard ratio [HR], 0.763). RESULTS A total 1,094 (intention treat), 1,068 eligible started their allocated treatment (arm 1, 543; arm 2, 525), completion protocol 68% v 54% 2). higher rate grade 3/4 adverse events reported experimental (14.4% 37.3% 23.4% 46.6% for neoadjuvant treatment, respectively). At a median follow-up 68 months (interquartile range, 58-74 months), 157 156 observed arms 1 respectively (adjusted HR, 1.02; 95% CI, 0.82 1.28; P = .835). Three-year not different, 76.5% (95% 72.7% 79.9%) which is than anticipated, 75.8% 71.9% 79.3%) 2. 7-year overall (OS) rates different as well, 66.1% 65.5% (HR, 1.02) OS 73.5% 73.7% 1.19) respectively. Subgroup analyses revealed heterogeneity effect according German versus non-German site location, detectable confounding factors multivariable analysis. CONCLUSION chemotherapy impairs tolerability feasibility does improve efficacy.