Diffuse large B-cell lymphoma and gastrointestinal Kaposi's sarcoma: a rare cause of upper gastrointestinal bleeding.

A 49-year-old man with a history of human immunodeficiency virus (HIV) infection, in a state of advanced immunosuppression and current antiretroviral therapy initiation. He was admitted to the hematology department after diagnosis of diffuse large B-cell lymphoma (DLBCL) associated with Epstein-Barr virus (EBV), disseminated cytomegalovirus (CMV) infection and cutaneous Kaposi's sarcoma (KS). During admission, he presented an episode of melena with anemization, so an urgent gastroscopy was performed. In the stomach there were multiple erythematous lesions, large and elevated, suggestive of subepithelial origin. Some of them presented an umbilicated center and other were ulcerated, covered with fibrin. The bulb and second duodenal portion showed similar involvement, large violaceous ulcerated lesions. Biopsies were taken and the anatomopathological diagnosis of the duodenal lesions was KS and of the gastric lesions KS and DLBCL associated with EBV. KS is an endothelial tumor associated with HIV. The stomach is the gastrointestinal organ most frequently affected and the typical endoscopic findings are nodular lesions. The stomach is the most common site of extranodal involvement in DLBCL. In both pathologies, the manifestation as upper gastrointestinal bleeding is exceptional and endoscopic biopsies can confirm the diagnosis.