A 74-year-old man was aware of a mass in the right axilla for three years. The patient presented to internal medicine clinic with pain in the right axilla. He had a markedly elevated serum soluble interleukin-2 receptor level, and 18F-fluorodeoxyglucose positron emission tomography showed diffuse uptake in lymph nodes. He began to complain of epigastric pain after meals. Esophagogastroduodenoscopy in our hospital revealed ulcerative lesions disseminated in the gastric body. Biopsy examination of gastric mucosal tissues showed the characteristic histological features of T-cell lymphoma, and biopsy examination of the right axilla showed the characteristic histological features of angioimmunoblastic T-cell lymphoma (AITL) . We encountered a rare case of AITL with diffuse gastric involvement.
