Purpose To evaluate neoadjuvant capecitabine/oxaliplatin before chemoradiotherapy (CRT) and total mesorectal excision (TME) in newly diagnosed patients with magnetic resonance imaging (MRI) –defined poor-risk rectal cancer. Patients and Methods MRI criteria for poor-risk rectal cancer were tumors within 1 mm of mesorectal fascia (ie, circumferential resection margin threatened), T3 tumors at or below levators, tumors extending ≥ 5 mm into perirectal fat, T4 tumors, and T1-4N2 tumors. Patients received 12 weeks of neoadjuvant capecitabine/oxaliplatin followed by concomitant capecitabine and radiotherapy. TME was planned 6 weeks after CRT. Postoperatively, patients received another 12 weeks of capecitabine. Results Between November 2001 and August 2004, 77 eligible patients were recruited. After neoadjuvant capecitabine/oxaliplatin, the radiologic response rate was 88%. In addition, 86% of patients had symptomatic responses in a median of 32 days (ie, just over one cycle of capecitabine/oxaliplatin). After CRT, the tumor response rate was increased to 97%. Three patients remained inoperable. Sixty-seven patients proceeded to TME, and all but one patient had R0 resection. Pathologic complete response was observed in 16 patients (24%; 95% CI, 14% to 36%), and in an additional 32 patients (48%), only microscopic tumor foci were found on surgical specimens. Four deaths occurred during neoadjuvant capecitabine/oxaliplatin therapy as a result of pulmonary embolism, ischemic heart disease, sudden death with history of chest pain, and neutropenic colitis. Conclusion Capecitabine/oxaliplatin before synchronous CRT and TME results in substantial tumor regression, rapid symptomatic response, and achievement of R0 resection.

Neoadjuvant Capecitabine and Oxaliplatin Followed by Synchronous Chemoradiation and Total Mesorectal Excision in Magnetic Resonance Imaging–Defined Poor-Risk Rectal Cancer