[Implantation Cyst at Anastomosis after Anterior Resection of the Rectum-A Report of Five Cases].

We report 5 cases of implantation cysts at anastomosis after rectal surgery. All patients underwent resection of the rectum usingthe double staplingtechnique (DST). Implantation cysts were recognized within a period of 3 months to 6 years after surgery. Abdominal CT showed cystic masses with calcification in all cases. Colonoscopy revealed submucosal tumor-like lesions in 3 cases, and serum CEA level was increased in 2 cases. In one patient with anal pain, transanal aspiration was performed; the other 4 patients are free from symptoms and are beingobserved without treatment.