Intrahepatic cholangiocarcinoma (ICCA) is a malignant epithelial neoplasm characterized by biliary differentiation within the liver. ICCA is molecularly heterogeneous and exhibits a broad spectrum of histopathological features. It is a highly aggressive carcinoma with high mortality and poor survival rates. ICCAs are classified into two main subtypes: the small-duct type and large-duct types. These two tumor types have different cell origins and clinicopathological features. ICCAs are characterized by numerous molecular alterations, including mutations inKRAS,TP53,IDH1/2,ARID1A,BAP1,BRAF,SAMD4, andEGFR, andFGFR2fusion. Two main molecular subtypes—inflammation and proliferation—have been proposed. Recent advances in high-throughput assays using next-generation sequencing have improved our understanding of ICCA pathogenesis and molecular genetics. The diagnosis of ICCA poses a significant challenge for pathologists because of its varied morphologies and phenotypes. Accurate diagnosis of ICCA is essential for effective patient management and prognostic determination. This article provides an updated overview of ICCA pathology, focusing particularly on molecular features, histological subtypes, and diagnostic approaches.
肝内胆管癌（ICCA）是一种具有胆管分化特征的原发性肝脏恶性上皮性肿瘤。该肿瘤具有分子异质性，组织病理学特征表现广泛，是一种侵袭性强、死亡率高、生存率低的恶性肿瘤。ICCA主要分为小胆管型和大胆管型两种亚型，这两种肿瘤类型具有不同的细胞起源和临床病理特征。ICCA以存在大量分子改变为特征，包括KRAS、TP53、IDH1/2、ARID1A、BAP1、BRAF、SAMD4和EGFR基因突变，以及FGFR2基因融合。目前主要提出炎症型和增殖型两种分子亚型。基于新一代测序技术的高通量检测进展，深化了我们对ICCA发病机制和分子遗传学的理解。由于ICCA形态学和表型多样，其病理诊断对病理医师构成重大挑战。准确诊断ICCA对患者有效管理和预后判断至关重要。本文重点围绕分子特征、组织学亚型和诊断方法，对ICCA病理学最新进展进行系统性综述。
Recent Advances in Pathology of Intrahepatic Cholangiocarcinoma
肿瘤(癌症)患者之家