A Case of Anaplastic Pancreatic Carcinoma Derived from Intraductal Papillary Mucinous Neoplasms

Abstract

Anaplastic pancreatic carcinoma is a rare subtype of invasive pancreatic ductal carcinoma. Here, we report an extremely rare case of anaplastic pancreatic carcinoma derived from intraductal papillary mucinous neoplasms (IPMNs).

A 77 year-old woman who had undergone a pancreatoduodenectomy for pancreatic head cancer 46 months previously was diagnosed with IPMN-derived invasive pancreatic ductal carcinoma (pT3N0M0, stage II A). She had completed 6 months of S-1 therapy when enlargement of the residual pancreas and dilatation of the main pancreatic duct were noted on follow-up computed tomography (CT). Therefore, detailed examinations were conducted, and magnetic resonance imaging (MRI) and positron emission tomography (PET) revealed a mass resulting in main pancreatic duct disruption and abnormal accumulation in the residual pancreas, respectively. The patient was diagnosed with adenocarcinoma based on the results of endoscopic ultrasound-guided fine-needle aspiration biopsy. After gemcitabine (GEM) plus S-1 therapy, residual pancreatectomy with left adrenalectomy, splenectomy, and lymph node dissection were performed. Histopathological findings indicated the histological transition from IPMN to adenocarcinoma and then to anaplastic carcinoma, confirming the diagnosis of IPMN-derived pleomorphic-type anaplastic pancreatic carcinoma (pT1cN0M0, stage IA).