Sipple''s syndrome is a multiple endocrinopathy usually involving the adrenal medulla and thyroid. In the present case, a malignant pheochromocytoma metastasized to the pericardium and both lungs. The patient had a calcified right suprarenal mass for 8 yr. He was admitted to the emergency room with symptomatology consistent with pericardial tamponade, but despite intensive management, he expired.