| [ Summary ] |
In surgically resected hepatocellular carcinomas (HCCs) less than 1.5cm in diameter, fatty change is found in 33.8% of the cases. Most are well-differentiated HCCs and fatty change is considered to be one pathomorphologic characteristic of small HCC in the early stages. However, the developmental mechanisms of fatty change in early-stage HCC are not yet fully understood. The frequency of HCC with fatty change is the highest in nodules ranging from 1.1 to 1.6cm in size. Intratumoral portal tracts decrease in tumors of around 1.5cm, while arterial tumor vessels are not yet well developed. Therefore, it is presumed that both the portal blood supply and arterial blood supply may be insufficient for those tumors, and the HCC nodules may become in ischemic. Such an insufficient blood supply seems to be the major factor in the development of fatty change. Fatty change is also frequent in other nodular lesions, such as atypical adenomatous hyperplasia, which is regarded as a borderline lesion and adenomatous hyperplasia containing cancerous foci. Fatty change is also observed in the early stages of experimental hepatocarcinogenesis. Thus, it is also thought that fatty change is closely related to hepatocarcinogenesis. |