[A Case of Gastric Cancer with Pericardial Effusion as an Immune-Reactive Adverse Events].

A 67-year-old man diagnosed with clinical Stage Ⅳ gastric cancer was administered nivolumab as fourth-line chemotherapy. After 9 courses, he was emergently admitted with complaints of low blood pressure and general malaise. On the fourth hospital day, he had high-grade fever and elevated serum C-reactive protein. Computed tomography showed a moderate amount of pericardial effusion. He was administered 1.7 mg/kg of methylprednisolone and improved rapidly. A hormonal blood examination showed his adrenal gland disorder. This is the first case in our country of pericardial effusion as an immune-reactive adverse event, which is not well known in Japan.