Histopathology and immunohistochemistry in intrahepatic cholangiocarcinoma

Abstract

Objective: The study aims to describe histopathological and immunohistochemistry characteristics in identifying intrahepatic cholangiocarcinoma. Subject and method: A total of 52 patients with intrahepatic cholangiocarcinoma between June 2018 and March 2020 were consecutive in the study. 16G core needle biopsies were implemented for all the patients and ensured the length of the biopsy specimens was at least 1.5cm. All liver specimens were processed according to standard histologic methods with Hematoxylin Eosin (HE) staining, and immunohistochemical staining on an automated Benchmark Ultra machine of Ventana (Roche). Histopathological classification according to The 2019 WHO classification. Result: Most of the intrahepatic cholangiocarcinoma was well-differentiated adenocarcinoma accounted for 40.4%, fibrous connective tissue accounted for 61.5%, and tumor necrosis accounted for only 15.4%. CK19 and CK7 were 100% positive and their expression frequently diffuse. CK20 and Hepar-1 were focal positive expressions for 13.5% and 18.2%, respectively. TTF1 only was positive at 12.5%. Conclusion: Histopathological features and strongly and diffusely positive expression of CK7, CK19, and positive Hepar-1 are very useful immunohistochemistry makers for diagnosis of ICC. However, TTF1 and CK20 also are positive expression at few rates.