Snapshot A 60-year-old man presents to his primary care physician reporting unintentional weight loss, night sweats, and fevers. He complains of a “strange” rash on his face that bothers him cosmetically. The rash does not hurt or itch. On exam, there are multiple well-demarcated red or purple macules and papules. He has a history of risky behaviors, including IV drug use and unprotected intercourse with multiple partners. His CD4 count comes back at 100/mm3. Introduction Malignancy of lymphatic endothelial cells Commonly affects skin lungs lymph nodes GI (especially in AIDS patients) Pathogenesis human herpes virus 8 genetic predisposition in some Epidemiological subsets AIDS most common AIDS-associated malignancy commonly seen in AIDS acquired through sexual contact rarely seen in AIDS acquired through injection drug use immunosuppression post-transplant classic sporadic usually in older men in people of Mediterranean origin endemic Eastern Africa Southern Africa 50% of childhood soft tissue tumors due to Kaposi’s sarcoma Presentation Symptoms B symptoms (fevers, night sweats, weight loss) painless skin lesions may have pain associated with internal lesions Physical exam red or purple lesions of varying morphologies macules/patches papules/plaques nodules common on face, oral mucosa, legs, and torso lymph nodes may be enlarged Evaluation Diagnosis by clinical exam Diagnosis confirmed with skin biopsy neoplastic spindle-shaped cells that form clefts and vascular channels Do CD4 count if AIDS is suspected Differential Diagnosis Melanoma Bacillary angiomatosis Pyogenic granuloma Treatment Anti-retroviral therapy majority will resolve Injection of vincristine or interferon If the above fail chemotherapy radiation Discontinue any immunosuppressants Prognosis, Prevention, and Complications Prognosis slow progression Prevention highly active anti-retroviral therapy for those with HIV infections annual skin exam in those at risk Complications metastatic progression