Adrenal Adenoma Anarchy: A Case of an ACTH-Secreting Pheochromocytoma

Introduction. Pheochromocytomas are rare neuroendocrine tumors that arise from sympathetic adrenomedullary chromaffin tissue. Depending on the amount of catecholamines they secrete, they have variable presentations. There have been reported cases of adrenocorticotrophic (ACTH) secreting pheochromocytomas that present with severe Cushing syndrome. Here, we present a pheochromocytoma with adrenocorticotrophic hormone (ACTH) cosecretion, which due to its rarity and variable presentation, may be a diagnostic challenge. Presentation. A 64-year-old woman with history of colon cancer presented with new-onset diabetes, worsening hot flashes, and hypertension. On CT imaging she had an enlarging right adrenal nodule (1.7 cm) with 60 Hounsfield units of attenuation and no PET avidity. Biochemical evaluation showed elevated urinary and plasma metanephrines, elevated plasma cortisol levels despite dexamethasone suppression, elevated late-night salivary cortisol, and high-normal adrenocorticotrophic hormone. The patient underwent laproscopic right adrenalectomy, and pathology confirmed pheochromocytoma. Her lab abnormalities and symptoms of hot flashes and hypertension improved postoperatively. Conclusion. This case demonstrates an unusual ACTH-secreting pheochromocytoma with subtle presentation and highlights the importance of obtaining a complete biochemical evaluation of incidental adrenal adenomas.