[A Case of Colostomy Cancer in a Very Elderly Patient Diagnosed 18 Years after Rectal Cancer Surgery].

A 93-year-old woman was admitted to another hospital because of pain during defecation at the colostomy, and was referred to our hospital because of a mass at the colostomy. She had undergone abdominoperineal resection for rectal cancer 18 years ago. A hard mass with poor mobility was palpable at the tip of the colostomy with a third-quarter circumference, and the outlet of the colostomy was stenosed. Biopsy of the mass revealed adenocarcinoma and we made a diagnosis as colostomy cancer. We decided to perform radical surgery, because it was suggested to be Stage Ⅱ disease. A circumferential skin incision was made 5 mm away from the colostomy. The colon used for the colostomy was separated from the extraperitoneal route, and the colostomy intestine tract was cut at 5 cm oral side from the tumor. Lymph node dissection was performed in D1 area. The neo-colostomy was reconstructed at the same site as before the surgery. The histopathological examination revealed moderately differentiated adenocarcinoma, pT3N0M0, pStage Ⅱa(JCCRC 9th edition). After discharge, she has been surveyed regularly without adjuvant chemotherapy.