Anaplastic Carcinoma of the Pancreas Possibly Associated with a Mucinous Cystic Neoplasm

Abstract

A 68-year-old woman presented with upper abdominal fullness. An abdominal CT scan showed a 13 cm multilobular cystic lesion with a solid component in the pancreatic body and tail. A CT scan one year previously showed a 2-cm cystic tumor in the tail of the pancreas, suggesting it had grown rapidly. Distal pancreatectomy and splenectomy combined with lymph node resection and total gastrectomy were performed. The tumor measured 16×11×5 cm and consisted of a cystic lesion and a solid component containing necrotic tissue inside. Histologically, the solid component represented anaplastic carcinoma (giant cell type) in continuity with a cystic lesion lined by mucinous epithelia. The cyst wall had focal hypercellular stromal cells showing calretinin positivity, indicating the presence of an ovarian-like stroma. These findings suggested anaplastic carcinoma associated with mucinous cystic neoplasm (MCN) of the pancreas, which is rarely reported.