For low-stage progressive rectal cancer, radical rectal cancer resection (total mesorectal excision, transanal TME) is performed through the anus, which mainly reflects the following advantages: 1. the bottom-up operation exposes the lower rectum and the surrounding tissue gap more clearly, which may reduce the positive rate of circumferential margin; 2. the combined push-up and pull-down exposure can reveal the pelvic nerve more effectively, which can reduce the side injury; 3. for low-stage rectal cancer, the margin is determined under direct vision, which increases the safety of the margin; 4. for male and obese patients with pelvic stenosis, it increases the chance of preserving the anus.