Avoidance of Overtreatment of Rectal Cancer by Selective Chemoradiotherapy: Results of the Optimized Surgery and MRI-Based Multimodal Therapy Trial.

2020

Background Neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer carries a high risk of adverse effects. The aim of this study was to examine the selective application of nCRT based on patient risk profile, as determined by MRI, to find the optimal range between undertreatment and overtreatment. Study Design In this prospective multicenter observational study, nCRT before total mesorectal excision (TME) was indicated in high-risk patients with involved or threatened mesorectal fascia (≤1 mm), or cT4 or cT3 carcinomas of the lower rectal third. All other patients received primary surgery. Results Of the 1,093 patients, 878 (80.3%) were treated according to the protocol, 526 pat…