S5486 Visceral Kaposi Sarcoma of the Liver and Stomach Without Cutaneous Involvement in a Patient with HIV/AIDS

Introduction: Kaposi sarcoma (KS) is a rare angioproliferative neoplasm caused by human herpesvirus-8 (HHV-8), most commonly affecting immunocompromised individuals, particularly those with HIV/AIDS. While KS typically presents with cutaneous lesions, visceral involvement—especially of the gastrointestinal and hepatic systems—is less common and often asymptomatic. Isolated hepatic and gastric involvement without skin manifestations is particularly rare. We present an unusual case of AIDS-related KS with hepatic and gastric involvement in the absence of cutaneous disease in a 25-year-old man with poorly controlled HIV. Case Description/Methods: A 25-year-old man with a history of HIV, non-adherent to antiretroviral therapy (ART), presented with a 2-year history of progressive dysphagia to solids and liquids, and a one-week history of nausea, vomiting, and nonbloody diarrhea. Physical exam was negative for violaceous or nodular lesions. HIV RNA viral load was 153,000 copies/mL, and CD4 count was < 20 cells/µL. HIV genotyping demonstrated infection with HIV-1 subtype B with E138A mutation. computed tomography (CT) imaging of the abdomen revealed numerous heterogeneous hepatic masses, the largest measuring 7.8 × 4 cm. Esophagogastroduodenoscopy (EGD) showed Los Angeles Grade D esophagitis with a distal esophageal stricture. Balloon dilation (8-9-10 mm) was performed. An 8-mm clean-based ulcer (Forrest Class III) was identified along the greater curvature of the stomach and biopsied. An ultrasound-guided liver biopsy was performed. Pathology demonstrated partial effacement of liver tissue by an atypical vascular proliferation. Immunohistochemistry performed on the biopsy showed expression of vascular markers (CD34, ERG1) and HHV8 latency associated nuclear antigen (LANA), confirming hepatic KS. A subsequent biopsy was performed on the gastric ulcer, showing an atypical spindled vascular proliferation that stained positive for CD31 and HHV8 LANA, confirming gastric KS. Discussion: Visceral KS without skin lesions is rare. Gastrointestinal and hepatic KS may present with dysphagia, abdominal pain, diarrhea, or be entirely asymptomatic. Our patient’s presentation underscores the importance of maintaining a high index of suspicion for visceral KS in immunocompromised patients, even in the absence of classic skin lesions. Early recognition and prompt initiation of ART and systemic chemotherapy are critical for improving outcomes.