Expression of laminin in HCC treated with transcatheter arterial embolization. Usefulness of laminin staining as a post-surgical detection procedure at the tumor invasion boundary.

The distribution of laminin was studied in sixty surgically resected hepatocellular carcinomas (HCC) treated with transcatheter arterial embolization (TAE) using immunoperoxidase procedure. When increased, laminin patterns consisted of thick basement membranes, organized in a trabecular pattern, and were lined by sinusoid structures. A marked increase of laminin was seen in 63.4% of well differentiated HCC, and in only 9.1% of poorly differentiated HCC. No laminin positive cases were found among 8 cases of adenomatous hyperplasia (AH) containing HCC foci. Thus, laminin patterns in HCC may be related to the degree of tumor differentiation. At the tumor-non tumor boundary, differential expression of laminin has made it possible to discriminate overt cancerous regions from normal tissues. Thus, laminin status proved to be an effective marker for tumor invasion in well-differentiated, laminin positive tumors. Assessment of HCC by laminin staining, together with a thorough and precise pathological examination of viable tumor cells after TAE treatment, may be recommended as a detection procedure for tumor invasion and for the transition from AH to the premalignant condition which culminates in HCC.