A Case of Gastrointestinal Kaposiʼs Sarcoma

Abstract

Kaposi's sarcoma (KS) is a neoplasm characterized by vascular nodules with a broad range of involvement, from cutaneous and lymphatic to visceral disease; it is the most common malignancy in HIV patients. The gastrointestinal (GI) tract is the most common extracutaneous site in AIDS patients and is associated with a poor prognosis; however, patients are usually clinically asymptomatic, making identification difficult. Recent studies have attempted to identify predictive factors of GI-KS. We describe a case of a 28-year-old man with melena. History is significant for a recent diagnosis of AIDS, after presenting with black skin lesions. Antiretroviral therapy (ART) was begun. Abdominal nodule biopsy was positive for HHV8, consistent with cutaneous KS. On presentation, patient was afebrile and normotensive. Physical exam significant for multiple purple papules. Laboratory studies revealed mild anemia, thrombocytopenia, elevated viral load of 172,498 copies/mL, and CD4 count of 56 cells/mcl. Upper endoscopy was performed for evaluation of melena. Endoscopic findings revealed protruding vascular masses in the gastric fundus and body and a flat vascular lesion in the duodenal bulb (Images 1-3). Immunostaining was positive for HHV8, confirming GI-KS. CT imaging demonstrated pulmonary and lymphatic involvement. Brain imaging demonstrated toxoplasmosis. Patient was continued on ART while receiving pyrimethamine/sulfadiazine for toxoplasmosis; systemic therapy for KS was held while this treatment was ongoing. Patient's cutaneous lesions continued to improve with ART; he had no further GI symptoms. CD4 count and viral load were 210 cells/mcl and 99 copies/mL, respectively, 6 weeks post-presentation. Characterization of the extent of disease is paramount in KS, as this dictates treatment and prognosis, with visceral disease requiring systemic therapy and associated with poor outcomes. Most patients with GI-KS are asymptomatic, with the majority of KS lesions found in the upper GI tract. Given the potential for severely advanced disease, the question is raised as to how to determine which KS patients should undergo endoscopy, given that the most common lesions are clinically silent. Recent studies suggest that in HIV patients, MSM status, ART-naïvity, CD4 count < 100 cells/mcl, HIV RNA ≥ 10,000 copies/mL, and cutaneous KS were associated with GI-KS. Clinicians should maintain a high index of suspicion for GI-KS in patients with these characteristics.1975_A Figure 1. Vascular mass of gastric fundus.1975_B Figure 2. Vascular mass of gastric body.1975_C Figure 3. Flat vascular lesion of duodenal bulb.