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.
KEY WORDS
hepatocellular carcinoma - premalignant lesion - multicentric occurrence
