Abstract
Hypercortisolemia and hypercatecholaminemia in ectopic adrenocorticotropic hormone (ACTH)-secreting pheochromocytoma represent life-threatening conditions, particularly when diagnosis is delayed. In this case, a 66-year-old male patient with poorly controlled diabetes presented with severe constipation in the absence of the classic Cushingoid phenotype. Computed tomography revealed bilateral adrenal masses, and (123)I-metaiodobenzylguanidine scintigraphy revealed radiotracer uptake in the left adrenal gland. Endocrine assessments confirmed elevated catecholamine, ACTH, and cortisol levels, indicating an ACTH-secreting pheochromocytoma. Despite preoperative management with osilodrostat and alpha-blockers, the patient experienced sudden cardiopulmonary arrest and succumbed. This case highlights that prompt diagnosis and intervention are particularly important in ACTH-secreting pheochromocytoma.