Kaposi's sarcoma: absence of cytomegalovirus antigens.

Using an immunohistochemical method, we could not detect cytomegalovirus antigens in the tissue of Kaposi's sarcoma but could in the cells of control sections from tissues known to be infected by that virus. Our results are consistent with the hypothesis that high antibody titers to cytomegalovirus found in patients with Kaposi's sarcoma are not due to infection of neoplastic cells by the virus, as a secondary event; our data supports the conclusions of others that exposure to cytomegalovirus may be a primary event in the pathogenesis of Kaposi's sarcoma.