Prominent hypereosinophilia with disseminated intravascular coagulation as an unusual presentation of advanced gastric cancer.

A 78-year-old woman was admitted to our hospital complaining of anorexia and purpura of the extremities. She presented with prominent peripheral eosinophilia and disseminated intravascular coagulation (DIC). Despite receiving intensive therapy for DIC, her illness worsened. Esophagogastroduodenoscopy revealed advanced gastric cancer (AGC), and a bone marrow biopsy led to a diagnosis of disseminated carcinomatosis of the bone marrow caused by AGC. We initiated combination chemotherapy with S-1 and cisplatin, which lead to a significant improvement of the DIC and eosinophilia, and the patient was finally discharged. The primary symptoms of DIC and eosinophilia were both considered to be caused by AGC, and we successfully treated the patient's critical condition.