Incidental atypical pheochromocytoma in sporadic type IIb von Hippel-Lindau disease

To describe the features of an incidentally discovered atypical pheochromocytoma in an asymptomatic patient with normal blood pressure and the de novo appearance of sporadic type IIB von Hippel-Lindau (VHL) disease.

We review the clinical manifestations, radiographic findings, and unusual features of a large, atypical pheochromocytoma diagnosed in a patient with the rare type IIB phenotype of VHL disease.

A 46-year-old man, who sought medical assistance in the emergency department after a motorcycle accident, had an abdominal roentgenogram that revealed extensive left suprarenal calcification. Computed tomography of the abdomen demonstrated a densely calcified left adrenal mass, bilateral renal cysts, and pancreatic calcifications. The patient was normotensive and asymptomatic and had no history of hypertension. He had undergone resection of a cerebellar hemangioblastoma at age 36 years and a partial left nephrectomy for a renal cyst at age 7 years. Routine biochemical screening demonstrated increased urinary vanillylmandelic acid and normetanephrine levels as well as an elevated plasma norepinephrine level. The adrenal mass was notable for the absence of increased signal intensity on T2-weighted magnetic resonance images. The patient was diagnosed with the type IIB phenotype of VHL disease and underwent resection of a 10.5-cm, 124-g benign pheochromocytoma.

Our case emphasizes the importance of recognizing that pheochromocytoma may occur in association with sporadic VHL disease, that not all pheochromocytomas have an increased signal intensity on T2-weighted magnetic resonance images, and that routine biochemical testing for pheochromocytoma is important in all patients with an adrenal "incidentaloma."