Characteristic Features of Cholangiocarcinoma Complicating Primary Sclerosing Cholangitis.

Background/Aims: Primary sclerosing cholangitis (PSC) is often complicated by cholangiocarcinoma (CCA); thus, early detection of CCA is an important way to improve PSC prognosis. Methodology: In a retrospective study, 23 cases of PSC were included. Seven cases were complicated by CCA (CCA group) and 16 cases were not (control group). Blood examinations, bile duct imagings from direct cholangiography, intraductal ultrasonography (IDUS) findings and pathological diagnosis results (bile juice cytology, brush cytology, and forceps biopsy) were referenced. Results: Blood examinations showed that serum carbohydrate antigen 19-9 (CA19-9), total bilirubin, and aspartate aminotransferase were significantly higher in the CCA group, whereas cholangiography showed that the dominant stricture was significantly longer in the CCA group. No significant difference in the IDUS findings was observed between the 2 groups. Cholangioscopy enabled CCA diagnosis via identification of the papillary mucosa in sites other than the stricture. Forceps biopsy was the most useful pathological diagnostic technique, with a sensitivity of 86% and a specificity of 100%. Conclusions: The CA19-9 level and bile duct stricture morphology were useful for diagnosing CCA complicating PSC. Aggressive performance of cholangioscopy and pathological diagnostic techniques, such as brush cytology and forceps biopsy, are essential for identification.