Expression of laminin in hepatocellular carcinoma: an adjunct for its histological diagnosis

In general, hepatocytes lack basement membrane structures and therefore no laminin expression is seen around hepatic cords. To determine whether or not laminin expression appears when hepatic tissue becomes carcinomatous, we carried out immunohistochemical staining of hepatic tissues excised surgically from 35 patients with hepatocellular carcinoma, 18 with metastatic colon carcinoma, two with adenomatous hyperplasia, and 10 without any nodular lesions. Among the various conditions of hepatic tissue, laminin expression was detected only in hepatocellular carcinoma with 86% positivity. The result was not dependent on the degree of differentiation. Therefore, it was confirmed that immunohistochemical detection of laminin provides a useful adjunct for the diagnosis of hepatocellular carcinoma, and this was verified by a study using needle biopsy samples. In addition, our results suggested that the basement membranes are derived from endothelial cells of either portal veins or hepatic arteries.