[A case of advanced gastric cancer associated with smouldering adult T-cell leukemia (ATL)].

A 43-year-old man was admitted to our clinic because of a 2-month history of anorexia, general fatigue and an upper abdominal mass. Upper GI series and endoscopic examination revealed Borrmann IV-type gastric cancer. The histologic diagnosis was undifferentiated adenocarcinoma. His peripheral blood contained approximately 3% atypical lymphocytes. These lymphocytes were identified to be ATL-cell based on E-rosette formation assays and anti-ATL associated antigen-antibody tests. Although the patient had no typical ATL-symptoms, we made a diagnosis of double cancer, i.e. gastric cancer and smouldering ATL. This is the first reported Japanese case of gastric cancer associated with smouldering ATL relationship between gastric carcinoma and other malignant diseases, especially ATL, is discussed.