结直肠癌是严重危害人类健康的常见恶性肿瘤。我国结直肠癌的发病率约为3.1/10万～10.7/10万,直肠癌所占比例可达70%,其中中低位直肠癌的比例可达70%～80%。20世纪末全直肠系膜切除(TME)的概念被逐渐接受并引入到直肠癌的手术治疗,使直肠癌的根治效果有了明显提高。与此同时,由于器械吻合技术的发展,解决了盆腔内低位肠吻合的问题,直肠癌保肛手术已经逐渐发展成为 Colorectal cancer is a common malignant tumor that seriously endangers human health. The incidence of colorectal cancer in China is about 3.1 / 100,000 to 10.7 / 100,000, the proportion of rectal cancer up to 70%, of which the proportion of low-grade rectal cancer up to 70% to 80%. The concept of total mesorectal excision (TME) was gradually accepted and introduced into the surgical treatment of rectal cancer in the late 20th century, which markedly improved the curative effect of rectal cancer. At the same time, due to the development of device anastomosis technology to solve the low pelvic anastomosis, anal sphincter preservation surgery has gradually developed into