[Long-Term Survival in Response to Multimodality Therapy in a Patient with Invasive Pancreatic Cancer with Cyst Formation].

: The patient was a 61-year-old man. Computed tomography(CT)in April 2007 revealed a pancreatic cyst in the tail of the pancreas. Rapid enlargement was noted in November 2007, and the patient was referred to the surgery department. CT showed a cystic lesion containing a nodular shadow in the pancreatic tail. Tumor marker measurements yielded normal carcinoembryonic antigen(CEA)and carbohydrate antigen 19-9(CA19-9)levels, but the duke pancreatic monoclonal antigen type 2(DUPAN-2)level was elevated. A diagnosis of mucinous cystic neoplasm(MCN)of the pancreas was made in December 2007, and distal pancreatectomy and partial colectomy were performed. The pathological diagnosis was a mucinous pancreatic cyst in the pancreatic tail and a moderately differentiated tubular adenocarcinoma that had invaded the spleen and serosal adipose tissue of the transverse colon. No clear ovarian-type stroma was detected, and there was no definitive evidence of MCN. The postoperative course was favorable and complication-free, and gemcitabine postoperative adjuvant therapy was administered. A metastasis was detected in the left lung in April 2011, and was excised. Chemotherapy was administered to the fifth-line, but the patient died of his cancer in August 2015, 7 years and 8 months after the initial surgery, and 4 years and 8 months after the detection of the lung metastasis. MCN and intraductal papillary mucinous neoplasm(IPMN)are typical mucus-producing pancreatic tumors, and they have a relatively good prognosis. Our patient had an invasive cancer associated with a mucinous pancreatic cyst, but no definitive diagnosis was made, and it was considered IPMN. The long-term survival appeared to have been achieved because of subsequent multimodality therapy.