Evaluation of the Extension of a Mucus-Producing Cystic Duct Primary Intracholecystic Papillary-Tubular Neoplasm Using Peroral Cholangioscopy: A Case Analysis

Abstract

We report a case of a 69-year-old man who visited his previous doctor with complaints of abdominal pain. Cholelithiasis pancreatitis was suspected based on blood test results and abdominal computed tomography (CT) findings, and endoscopic retrograde cholangiopancreatography (ERCP) was performed. Mucus outflow was observed from the bile duct, and a mucus-producing tumor derived from the bile duct was suspected. He was referred to our hospital for scrutiny. Contrast-enhanced CT showed elevated lesions with early dark staining and late washout confined to the gallbladder duct. Endoscopic ultrasound (EUS) showed a papillary mass in the cystic duct as the main observation. The mass was exposed at the opening of the cystic duct, but no extension into the bile duct was observed. Biliary tract observation revealed a reddish papillary ridge exposed from the cystic duct to the bile duct side, but the mucosa around the opening was normal. Based on these observations, the patient was diagnosed with suspected primary cystic duct cancer and underwent surgical resection. Histopathological examination revealed intracholecystic papillary-tubular neoplasm, and the tumor was localized to the cystic duct. We report a self-study that met Farrar's diagnostic criteria with a literature review.