Immunohistochemical examinations of lesions from both cases showed a strong reaction with endothelial markers (CD31, CD34, and D2-40) and HHV-8 (LNA-1) both in endothelia of the cavernous hemangioma-like vascular structures and at the areas of early-stage KS. This evidence concerns the gene PECAM1 and cavernous hemangioma.