The Highs and Lows of an Unknown Pheochromocytoma in an Elderly Patient.

Pheochromocytomas are rare catecholamine producing neuroendocrine tumors. The incidence of these tumors is estimated to affect 0.8 per 100,000 person-years and is most common in the fourth to fifth decade of life with equal prevalence in men and women. We describe a case of an 84-year-old male who presented with cycling episodes of severe hypertension and hypotension after an elective cardiac catheterization. Workup of the labile blood pressure revealed a large suprarenal mass and free serum metanephrines (MN) 104 nmol/L (reference range 0.0-0.49 nmol/L) and normetanephrines (NMN) of 24 nmol/L (reference range 0.0-0.89 nmol/L), confirming the diagnosis of a pheochromocytoma. The patient's labile blood pressure was a challenge to manage medically and improved only after aggressive hydration and an alpha-adrenergic antagonist. Of note, this is the second eldest patient known to be published to date with a pheochromocytoma.