MORPHOLOGICAL CHARACTERISTICS COMBINED HEPATOCELLULAR-CHOLANGIOCARCINOMA
Combined hepatocellular-cholangiocarcinoma (cHCC-CC) refers to rare forms of malignant liver tumors. The analysis of literature data on the morphological study of cHCC-CC is carried out. We emphasized that accurate diagnosis of cHCC-CC is possible only with microscopic examination of histological preparations of biopsy or surgical material stained with hematoxylin and eosin. The main structural feature of cHCC-CC is a combination of elements of hepatocellular carcinoma and intrahepatic cholangiocarcinoma. The microscopic characteristics of hepatocellular differentiation include the trabecular or pseudo-glandular structure of the tumor with the presence of Mallory bodies in the tumor cells and signs of bile secretion. Glandular structures, desmoplastic stroma and signs of mucin production are evidence of the cholangiocellular nature of the tissue. An immunohistochemical study with hepatocyte and biliary markers, as well as stem cell markers, is recommended as an additional method. The hepatocellular component is characterized by a positive immunohistochemical reaction with antibodies HepPar1, pCEA, CD10 and glypican 3. The reaction with CK7, CK19 antibodies and mucin staining are noted in the areas of the cholangiocellular component. The use of data from preoperative radiological studies, which allow for targeted biopsy and targeted morphological examination of the surgical material, is the key to successful diagnosis and, accordingly, treatment of cHCC-CC.