Angioproliferative changes in clinically noninvolved, perilesional skin in AIDS-associated Kaposi's sarcoma.

In clinically noninvolved skin from the area surrounding early macular lesions of AIDS-associated disseminated Kaposi's sarcoma (KS), morphological evidence of vascular proliferation was seen in the upper papillary dermis. Poorly differentiated cells with cytoplasmic inclusions similar to Weibel-Palade bodies were found to form primitive vascular lumina. Around the vessels, dermal Langerhans' cells and lymphoid cells were detected. Spindle-shaped cell proliferation characteristic of fully developed KS lesions was not observed. The angioproliferative changes, undetectable clinically, were similar, though less evident, to those observed in early lesions of disseminated KS, but without stroma tissue reaction. These findings suggest that in AIDS-associated KS angioproliferation may not be restricted to the clinically detectable lesions and that some angioplastic factor(s) may cause widespread endothelial hyperproliferation.