病例资料我科2009年1月至2011年1月期间对4例低位直肠癌患者行括约肌间直肠切除术(ISR),男2例,女2例,年龄46~62岁。均为肿块型,2例为绒毛状腺瘤术后复发并局部癌变,2例为中分化腺癌。肿瘤下缘距肛缘2.0~4.5 cm。术前MRI确定肿瘤局限于直肠壁内,无排便功能障碍,无远处转移。手术方法:全麻下取截石位,首先 Case data Our department from January 2009 to January 2011 four low rectal cancer patients underwent sphincterotomy (ISR), 2 males and 2 females, aged 46 to 62 years. Both were tumor type, 2 cases of villous adenoma recurrence and local cancer, 2 cases of moderately differentiated adenocarcinoma. Tumor margin from the verge of 2.0 ~ 4.5 cm. Preoperative MRI to determine the tumor confined to the rectal wall, no defecation dysfunction, no distant metastasis. Surgical methods: general anesthesia to take lithotomy position, first of all