Premalignant lesions of cholangiocarcinoma: characteristics on ultrasonography and MRI

• Main Authors: Surachate Siripongsakun, Withawat Sapthanakorn, Poemlarp Mekraksakit, Saruda Vichitpunt, Saowalak Chonyuen, Jitsupa Seetasarn, Siwat Bhumiwat, Thaniya Sricharunrat, Saowanee Srittanapong
• Other Authors: Faculty of Medicine, Ramathibodi Hospital, Mahidol University
• Format: Article
• Published: 2020
• Subjects: Health Professions; Medicine
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/50956
• Institution: Mahidol University

© 2019, Springer Science+Business Media, LLC, part of Springer Nature. Background and objective: Cholangiocarcinoma (CCA) is an aggressive malignancy with high prevalence rate in Asia. The CCA premalignant lesions, including Biliary intraepithelial neoplasia (Bil-IN) and Intraductal papillary neoplasm of biliary tract (IPNB), share a common carcinogenesis; however, on imaging, patterns of presentation are different. Patterns and imaging characteristics on ultrasonography (US) and Magnetic resonance imaging (MRI) of both Bil-IN and IPNB are reported herein. Methods: In this retrospective study of imaging findings in premalignant CCA, pathology-proven cases of Bil-IN and IPNB at Chulabhorn Hospital were analyzed. Demographics, locations of lesions, imaging characteristics of both Bil-IN and IPNB were assessed, compared, and described. Results: Twenty-one premalignant lesions, 13 Bil-INs and 8 IPNBs, from 18 patients were included. Both Bil-IN and IPNB lesions were found more commonly at the right than left intrahepatic ducts (66.7% vs. 33.3%), and had more peripheral than central locations (85.7% vs. 14.3%). On US, Bil-IN commonly presented as focal bile duct dilatation (76.9%), whereas IPNB was more variable with hyperechoic nodules (37.5%), focal bile duct dilatation (37.5%), and diffuse bile duct dilatation with intraductal nodules (25%). On MRI, focal bile duct dilatation and nonfunctioning bile excretion are the most sensitive findings with sensitivities in the range of 84.6% to 100%. The presence of intraductal nodules and connection to the biliary system are findings that were significantly different between IPNB and Bil-IN, 62.5% versus 7.7% (p = 0.014) and 75% versus 15.4% (p = 0.018), respectively. Conclusions: Premalignant lesions of CCA, including Bil-IN and IPNB, have different imaging presentations. Knowledge of imaging presentations may improve early detection and increase confidence in diagnosis.