PECAM1 and Kaposi's sarcoma: Histopathological examination showed two distinct but intermingled neoplastic components: one component displayed effaced nodal architecture with atypical clear cells positive for CD3, CD4, CD10, PD-1, and Bcl-6, consistent with AITL; the second component demonstrated red blood cell extravasation, spindle cell proliferation forming slit-like vascular spaces, positive for HHV-8 LANA-1, ERG, CD31 and CD34, consistent with Kaposi sarcoma (Figure 2).