A Case of Cured Diabetes Mellitus after Occult Malignant Pheochromocytoma Removal

Abstract

Pheochromocytoma is characterized by a combination of various clinical manifestations that include the classic triad of severe headache, palpitations and diaphoresis. In addition, hyperglycemia can be caused by overproduction of catecholamines, which are secreted by a catecholamine-secreting neoplasm of adrenal or extra-adrenal chromaffin tissue. We encountered a case of diabetes with an occult malignant adrenal pheochromocytoma, who did not have any classic manifestations. A 37-year-old male was admitted because of polydipsia, polyuria, and weight loss. Fasting blood glucose level was 497 mg/dL, hemoglobin A1c level was 15%, and diabetic retinopathy and peripheral polyneuropathy were also accompanied. Incidentally, right adrenal mass was detected by ultrasonography of abdomen. Urinary excretion of total metanephrine and epinephrine were elevated. Adrenal CT showed a 7.1 cm sized right adrenal cystic mass with enhancing solid portion and hemorrhagic content. The scan with 123I-MIBG revealed the cystic mass with increased rim uptake in the region of right adrenal gland. After removal of the tumor, the increased levels of catecholamine were normalized. Moreover, blood glucose level was normalized without administration of insulin or oral hypoglycemic agents. The pathologic examination showed that the neoplasm was a malignant adrenal pheochromocytoma. We report this case that diabetes was cured after removal of malignant tumor with literature review at first in Korea. (J Kor Diabetes Assoc 31:520~524, 2007)