Distribution of immunocompetent cells in oral Kaposi's sarcoma (AIDS).

Fifteen biopsy specimens of oral AIDS-associated Kaposi's sarcoma (KS), 19 biopsy specimens of uninvolved oral mucosa of HIV-seropositive patients (HIV+) and 22 biopsy specimens of oral mucosa of HIV-seronegative persons (HIV-) were analysed for the distribution of CD4+ and CD8+ lymphocytes and HLA-DR+ cells. The results were statistically evaluated. According to their clinical appearance KS were classified as flat lesions (n = 10) or exophytic tumours (n = 5). KS lesions of both clinical groups as well as uninvolved mucosa of HIV+ patients revealed infiltration with CD4+ cells. In flat, patch-like KS there was a marked increase of CD8+ cells compared to HIV- mucosa, while their numbers decreased in later tumour stages. In both, flat and exophytic KS the number of HLA-DR+ cells was significantly higher than in uninvolved mucosa of HIV+ and HIV- persons. These findings may reflect the local influence of KS growth factors on the inflammatory reaction in the setting of systemic immunosuppression.