[A Case of Anastomotic Recurrence of Rectal Cancer 22 Years after Surgery].

In general, anastomotic recurrence of colorectal cancer occurs within 3 years after surgery. We encountered an extremely rare case of anastomotic recurrence over 20 years after surgery. A 70-year-old woman who had undergone low anterior resection for rectal cancer 22 years previously was admitted to the hospital because of anal bleeding. Colonoscopy revealed a 1.5 cm sized, elevated lesion on the anastomotic site, and a biopsy revealed an adenocarcinoma(tub2). EUS demonstrated that the tumor was located on the staples, and the depth of the tumor was expected to be within the muscle layer of the rectum. Computed tomography showed no signs of distant metastasis. Given the diagnosis of anastomotic recurrence of rectalcancer 22 years after surgery, laparoscopic abdominoperinealresection was performed. Histologicalassessment showed that the tumor was on the staples, and did not exhibit vascular and lymphatic invasion. Finally, she was diagnosed with anastomotic recurrence due to implantation. The patient has exhibited no other signs of recurrence in the 3 years since the last surgery.