[A Case of Low Grade Dysplastic Intracystic Papillary Neoplasm Occurred in Young Woman].

The patient is a 41-year-old woman. She had been regularly visiting our hospital for follow-up of primary biliary cirrhosis and gallbladder polyps, but was referred to the Department of Surgery for surgery because the polyps tended to enlarge in size. Abdominal CT showed a 10 mm-sized polyp with early contrast in the body of the gallbladder, and T2-weighted abdominal MRI showed a signal defect in the gallbladder lumen consistent with a polyp, but a qualitative diagnosis was difficult. Laparoscopic cholecystectomy was performed for diagnostic and therapeutic purposes. The macroscopic findings of the resected specimen showed a 12 mm-sized papillary lesion in the body of the gallbladder, which was diagnosed as a low-grade intracystic papillary neoplasm (ICPN) on histopathologic examination. No invasion was observed and the margins were negative. ICPN is a recently defined disease that is considered similar to intraductal papillary neoplasm of bile duct (IPNB), which develops in the gallbladder. Although most of them are diagnosed with cancer, we report a rare case of IPNB without cancer.