Immunohistochemical examination of lesions of both cases revealed a strong positive reaction with endothelial markers (CD31, CD34, and D2-40) and HHV-8 (LNA-1) in both endothelial lining of cavernous hemangioma-like vascular structures and at areas of typical early-stage KS. This evidence concerns the gene PECAM1 and Kaposi's sarcoma.