Kaposi's sarcoma in a Korean living in Japan. Review of cases reported in Japanese literature.

An 87-year-old male Korean living in Japan had the typical classic lesions of Kaposi's sarcoma on the extremities. Numerous red-purple nodules and plaques were observed on the edematous forearms and lower extremities. Histologic examination revealed an extensive proliferation of spindle cells and large endothelial cells, which were both positive for factor VIII-related antigens. The patient's sera were positive for IgG antibodies to late antigens of cytomegalovirus and negative for IgM antibodies to late antigens of cytomegalovirus and for IgG antibodies to early antigens of cytomegalovirus. Cytomegalovirus-related antigens were detected in the nucleus or cytoplasm of cells in the biopsy specimens by the anticomplement immunofluorescence (ACIF) test. These results suggest that cytomegalovirus infection might play a role in the development of Kaposi's sarcoma, though it is premature to draw any definite conclusion in this connection. In addition, the characteristics of histologic and clinical findings of Kaposi's sarcoma cases reported in the Japanese literature have been discussed.