Transpapillary intraductal ultrasound in the evaluation of dominant bile duct stenoses in patients with primary sclerosing cholangitis

OBJECTIVE: Primary sclerosing cholangitis (PSC) is associated with the development of cholangiocarcinoma (CC) in approximately 9% of patients. Neither cholangiography nor endoscopic tissue sampling can reliably distinguish between CC and benign dominant bile duct stenosis. The aim of the present study was to assess the value of intraductal ultrasonography (IDUS) in distinguishing between benign and malignant dominant stenoses in PSC patients. MATERIAL AND METHODS: Forty PSC patients with dominant bile duct stenoses were studied prospectively. Transpapillary IDUS and endoscopic tissue sampling were performed in addition to endoscopic retrograde cholangiography (ERC). Cholangiography and IDUS findings were classified as malignant or benign by the investigators. Final diagnosis of malignant stenosis was based on positive histology and/or cytology, whereas a benign character was assumed in cases of negative tissue sampling and uneventful extended clinical follow-up. RESULTS: Eight PSC patients (20%) had dominant bile duct stenoses caused by CC, whereas 32 out of 40 patients (80%) had benign dominant bile duct stenoses. IDUS was significantly superior to ERC for detection of malignancy in terms of sensitivity (87.5% versus 62.5%, p=0.05), specificity (90.6% versus 53.1%, p<0.001), accuracy (90% versus 55%, p<0.001), positive predictive value (70% versus 25%, p<0.001), and negative predictive value (96.7% versus 85%, p=0.049). CONCLUSIONS: Transpapillary IDUS significantly increases the ability to distinguish malignant from benign dominant bile duct stenoses in patients with PSC.