IMMUNOHISTOCHEMISTRY AND ANGIOGRAPHY IN ADENOMATOUS HYPERPLASIA AND SMALL HEPATOCELLULAR CARCINOMAS

The sinusoidal structure and blood supply of 38 liver nodules less tha n 2 cm in diameter were investigated. There were 18 cases of adenomato us hyperplasia (AH) and 20 cases of hepatocellular carcinoma (HCC). Gr owth pattern, encapsulation and vascularity were examined, and immunoh istochemistry performed for factor VIII related antigen (factor VIII), type IV collagen (collagen IV), laminin and CD68. There were signific ant differences between AH and small HCC, except for the expression of CD68. There were differences in tumor size, vascularity and the compo nents of the basement membrane between AH and small, well differentiat ed HCC. The cases of AH were supplied by the portal system and maintai ned the sinusoidal structure, but small well-differentiated' HCC were supplied by a mixture of portal and arterial vessels. In spite of thei r small size, moderately and poorly differentiated HCC had capillary a nd were supplied by branches of the hepatic artery.