Multinucleate cell angiohistiocytoma:: report of two cases with no evidence of human herpesvirus-8 infection

Multinucleate cell angiohistiocytoma (MCA) is a vascular tumor of unknown pathogenesis. Possible misinterpretation of this disorder with Kaposi's sarcoma (KS), a human herpesvirus-8 (HHV-8)-associated tumor, prompted us to look for this virus in two women with MCA. None of the multiple skin specimens obtained from both our patients produced amplified HHV-8 DNA. Using a cell culture methodology similar to that used for KS, we established cell cultures from MCA lesions. While KS spindle cells are known to exhibit in vitro invasive properties and can be grown up to more than 20 passages, the MCA-derived cells were short-lived and were not able to traverse basement membranes. Taken together, our data support the hypothesis that MCA is not a neoplasm but a benign vascular proliferation which is clearly distinguishable from KS.