Branch-duct IPMN with an atypical appearance on imaging

Abstract

A woman in her 70s was admitted with a cystic lesion in the pancreatic body. With no elevation of tumor markers, a CT scan incidentally demonstrated a 10mm solid lesion in the caudal part of the original cystic lesion, with delayed contrast enhancement. EUS showed a small cystic space around that lesion. Since the lesion had no findings suspicious for malignancy, it was followed for 17 months with imaging studies. During this period, no remarkable changes were seen on imaging. However, to establish the diagnosis, we performed EUS-FNA resulting in a histological diagnosis of branch duct IPMN (BD-IPMN). Due to these abnormal findings, distal pancreatectomy was performed, and the diagnosis of BD-IPMN of gastric type without malignant features was confirmed. The tumor occupied most of a cyst, consistent with the preoperative findings. However, it had a different gross appearance from typical BD-IPMN. We report a BD-IPMN with an atypical shape.