Abstract
The current study indicates the case of intracholecystic papillary neoplasm (ICPN) protruding into the common bile duct (CBD) without superficial spread. A 58-year-old woman presented to hospital with a fever that lasted for three days. Laboratory tests revealed elevated hepatobiliary enzyme levels. CT, MRI and endoscopic ultrasonography revealed a polypoid, papillary tumor inside the gallbladder cavity, which also extended to the CBD. On peroral cholangioscopy, a papillary tumor with mucin production was found at the middle bile duct. Biliary biopsy and bile cytology indicated adenocarcinoma. Based on a diagnosis of ICPN extending to the CBD, the patient underwent subtotal stomach-preserving pancreaticoduodenectomy and gallbladder bed resection. However, pathological examination revealed that the ICPN was confined to the gallbladder and cystic duct, whereas the CBD was tumor-free. The present case indicates that when ICPN increases in size, it may protrude into the CBD due to an increased intracholecystic pressure, which increases the risk of overestimation of tumor extension and may result in unnecessary additional bile duct resection.