[Intraductal Papillary Mucinous Carcinoma with Penetration in the Colon and Retrograde Infection-A Case Report].

We report a case of intraductal papillary mucinous carcinoma(IPMC)penetrating the colon in an 82-year-old man. He visited our hospital with left upper abdominal pain. Abdominal CT showed IPMC of the pancreatic tail, measuring 7 cm, with tumor penetration to the colon and retrograde infection. After the antibacterial treatment, we performed distal pancreatectomy with colectomy. Pathological examination showed proliferation of adenocarcinoma of the gastrointestinal tract with penetration to the colon. Severe fibrosis and calcification surrounding the invasive cancer cells suggested a long disease duration. Despite adjuvant chemotherapy, he developed recurrence of peritoneal dissemination after 9 postoperative months, and subsequently, systemic chemotherapy was started. As intraductal papillary mucinous neoplasm(IPMN)might penetrate the adjacent organs, leading to a poor prognosis, even over a prolonged time period, IPMN should be followed-up appropriately and resected soon after the suspicion of malignant transformation.