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

Multinucleate cell angiohistiocytoma (MCA) is a vascular tumor of unknown p athogenesis. Possible misinterpretation of this disorder with Kaposi's sarc oma (KS), a human herpesvirus-8 (HHV-8)-associated tumor, prompted us to lo ok for this virus in two women with MCA. None of the multiple skin specimen s obtained from both our patients produced amplified HHV-8 DNA. Using a cel l culture methodology similar to that used for KS, we established cell cult ures 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 membr anes. Taken together, our data support the hypothesis that MCA is not a neo plasm but a benign vascular proliferation which is clearly distinguishable from KS.