Background: The standard treatment for low rectal cancer (LRC) involving the anal sphincter involves combined, pre-operative chemotherapy and radiotherapy (CRT) followed by surgery. Surgery involves removal of the rectum and anus and creation of a permanent colostomy and has significant long term effects on bowel and sexual function and body image. Because of the high morbidity of surgery, there has been increasing interest in non-operative management (NOM) for LRC. The NOM approach involves deferral of surgery and active surveillance of all patients with LRC who have achieved a complete clinical response (i.e., have no residual tumour) following completion CRT which occurs in approximately 30% of patients. To date, while there have been a few, prospective single institution studies that have shown favourable results with NOM, this approach has not been adopted into clinical practice due to concerns from physicians about the safety of NOM based on the limited evidence available.