Tissue of origin of Kaposi sarcoma is:

Kaposi sarcoma, a vascular tumor ,induced by HHV 8 Incidence of kaposi sarcoma increased dramatically during AIDS epidemic ,now decreased 10 fold with highly active retroviral therapy The lesions of KS are characterized by the proliferation of spindle-shaped cells that express markers of both endothelial cells and smooth muscle cells. There is also a profusion of slit like vascular spaces, suggesting that the lesions may arise from primitive mesenchymal precursors of vascular channels. KS lesions display chronic inflammatory cell infiltrates. Solid organ transplant (SOT) patients are highly susceptible to development of KS Kaposi's sarcoma is 550-1000 times M/C among SOT recipients than in normal population