Background: Pheochromocytoma (PHEO) is a rare tumor of the adrenal medulla and sympathetic ganglion that produces the catecholamines norepinephrine and epinephrine. Traditionally, approximately 10% of PHEOs were thought to be malignant, but recent developments in PHEO research have noted that specific genetic mutations are associated with higher risk of metastatic spread.
Case report: We report the case of a 71-year-old female who presented with abdominal pain in September 2009 when she was 64 years old. Evaluation at that time revealed cholelithiasis and bilateral adrenal masses. Workup showed elevated free normetanephrines, and positron emission tomography-computed tomography demonstrated bilateral adrenal hypermetabolic lesions concerning for malignancy. She underwent open bilateral adrenalectomies and cholecystectomy. The right adrenal mass was identified as a PHEO with nonaggressive features and negative margins, and the left adrenal mass was an adrenal cortical adenoma without dysplasia. In April 2016, the patient was referred by her endocrinologist for elevated blood pressure and 16-lb weight loss. The patient reported weakness, headaches, hot flashes, cold sweats, and fatigue. Laboratory workup revealed elevated plasma free normetanephrine, and imaging showed a recurrence of the PHEO in both the right adrenal bed and the head of the right humerus.
Conclusion: Current predictors of PHEO recurrence failed to identify the original tumor as aggressive or likely to return as a metastatic lesion. Because of the rarity of these tumors, few consistent laboratory or radiologic predictors of malignancy based on initial presentation have been identified; predictors of malignancy in PHEO warrant further investigation.
Keywords: 3-Iodobenzylguanidine; neuroendocrine tumors; pheochromocytoma.