This is a 5 year Phase II study to evaluate the safety of non-operative management (NOM) in patients with low rectal cancer (LRC) who achieve a complete clinical response (cCR) following chemoradiotherapy (CRT). The safety of NOM will be evaluated by assessing (i) rate of local re-growth and (ii) rate of macroscopically positive resection margin (R2) when surgery is required due to local re-growth. NOM will be considered safe or as effective as surgery to achieve local control if the rate of local re-growth is equal to or less than 30% and the rate of a macroscopically positive margin is 0%.