[Pathomorphologic study on early hepatocellular carcinoma (HCC)--a study of cell density in well-differentiated HCC of the early stage].

In order to clarify the histologic characteristics of well-differentiated hepatocellular carcinoma (HCC), a comparative morphometric study on cell density was performed in 15 HCCs smaller than 2 cm in diameter, 6 HCCs with marked fatty and/or clear cell change, 7 hyperplastic nodules, 5 hyperplastic nodules containing foci of HCC, and non-cancerous areas of the livers bearing small HCC. In well-differentiated HCC, marked increase of cell density accompanying by decrease of cell size and increase of nuclear cytoplasm ratio were prominent, and the cell density was approximately two times larger than that of the non-cancerous area in most cases. In HCCs with marked fatty and/or clear cell change, as an increase of cell density was not evident because of swelling of the cytoplasm due to fat and/or glycogen accumulation, it should be careful to differentiate them from non-cancerous nodular lesions including hyperplastic nodule with marked fatty change. Hyperplastic nodules could be divided into two groups; those with marked increase of cell density, and those without increase of cell density. In the former group, 5 of the 7 nodules contained cancerous foci.