A Case of Intracystic Papillary Neoplasm Incidentally Diagnosed during Laparoscopic Cholecystectomy

Abstract

An 83-year-old man was admitted to our hospital with the complaint of epigastric pain. He was diagnosed with gallstone pancreatitis, and a temporary bile duct placement was performed. Subsequently, laparoscopic cholecystectomy was performed for the removal of residual gallbladder stones. Intraoperatively, because of tissue sclerosis （mainly in the Calot’s triangle and the neck of the gallbladder）, we removed the gallbladder after dissecting the hepatic bed from the fundus of the gallbladder, and dissecting the cholecystic artery and cholecystic duct. Gross examination of the excised specimen showed a 13-mm papillary protuberance in the body of the gallbladder. Histopathological examination showed that it was a low-grade, atypical, papillary proliferation of the gallbladder epithelium. The lesion was diagnosed as an intracystic papillary neoplasm （ICPN）. ICPN is considered to be an intraductal papillary neoplasm of the bile duct growing within the gallbladder. This disease is poorly recognized, and only a limited number of cases have been reported. They are often diagnosed together with cancer because they are precancerous lesions. Because it is very rare to have an incidental diagnosis of ICPN without a concurrent cancer, we report this case along with a review of literature with this condition.