Immunohistochemical expression of metallothionein in resected hepatic primary tumors and colorectal carcinoma metastases

Metallothionein is a protein with affinity for metals and is present in several tumors. We examined its immunohistochemical expression in 37 resected primary liver tumors and 117 colorectal metastases. The reaction was intense in the two fibrolamellar hepatocellular carcinomas and in many of the hepatocytes of the pseudotumor case of focal nodular hyperplasia. The reaction was low or moderate in 5 of 17 ordinary hepatocellular carcinomas and in 4 of 14 cholangiocellular carcinomas. There was no reaction in one case each of spindle cell hepatocellular carcinoma, oncocytic adenoma and hemangioendothelial sarcoma. In the metastases, the reaction was low or moderate in 14 cases and negative in 103. Surrounding hepatocytes and stromal cells were more or less positive in all cases.