title: Histopathologic evaluation of hepatocellular carcinoma with special reference to small early stage tumors.
abstract: Over the past decade extensive studies on small early stage hepatocellular carcinomas (HCCs) have defined their pathomorphologic features. Most early HCCs are well differentiated, with an ill-defined nodular appearance. Proliferation of well-differentiated small HCCs is closely related to tumor dedifferentiation. When a well-differentiated HCC reaches a size of about 1.0-1.5 cm in diameter, less-differentiated cancerous tissues with greater proliferative activity evolve within it. Such a phenomenon is often appreciated grossly and/or histologically as a "nodule-in-nodule" appearance. Subsequently, moderately to poorly differentiated HCC tissues gradually replace the initial surrounding HCC. This replacement of well-differentiated HCC tissue is completed when the tumor reaches a size of about 2-3 cm. Hyperplastic nodular lesions in cirrhotic livers may have a premalignant potency. HCC frequently occurs multicentrically whether synchronously or metachronously, defying complete cure by conventional therapies other than liver transplantation.
authors.affiliation: Department of Pathology, Kurume University, School of Medicine, Japan. kojiro@med.kurume-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kojiro
authors.forename: O
authors.initials: O
authors.lastname: Nakashima
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia; D008103:Liver Cirrhosis / Q000473:pathology; D008113:Liver Neoplasms / Q000473:pathology*; D011230:Precancerous Conditions / Q000473:pathology