Endocrine Abstracts

Pheochromocytomas are rare adrenal tumors that produce catecholamines and may cause severe cardiovascular events. Even rarer are adrenal tumors that present with co-secretion of cortisol, which add metabolic, immunosuppressive, and psychiatric complications.

Case Presentation: A 34-year-old woman with a complex history—including long QT syndrome, ventricular fibrillation and cardiac arrest, Takotsubo cardiomyopathy, Graves’ disease (in remission), and an implantable cardioverter-defibrillator—had a history of a left adrenal mass increasing from 2 cm to 3.8 cm. She experienced a cardiac arrest in April 2024, attributed to long QT. In March 2025, she presented with hypertensive crisis, mood changes, headache, and chest pain. Biochemical analysis showed non-suppression of cortisol post overnight 1 mg dexamethasone (>2500 nmol/l), elevated ACTH (130 pmol/l), markedly raised normetanephrine (>50,000 pmol/l), androgen excess, hypokalaemia (2.4 mmol/l), and a normal aldosterone-renin ratio. Imaging including MIBG scan confirmed a heterogeneous left adrenal lesion consistent with pheochromocytoma. Pituitary MRI was normal.

Treatment and Outcome: Pre-operative alpha-blockade was initiated, followed by robotic left adrenalectomy in April 2025. Post-operatively, Hydrocortisone replacement prevented adrenal insufficiency. Histology confirmed pheochromocytoma with adrenal cortical hyperplasia (30 × 15 × 34 mm, PASS 4/20, GAPP 3/10, Ki-67 <1%). Genetic testing was negative, suggesting an acquired type. By June 2025, biochemical markers normalized, including catecholamines, cortisol, ACTH, and androgens, with stable electrolytes and renal function. Patient reported significant improvement in her symptoms.

Conclusion: This case highlights the complex presentation of pheochromocytomas with hypercortisolism and hyperandrogenism with raised ACTH, a normal pituitary MRI, and normalization of ACTH post-surgery, suggesting paraneoplastic/ectopic pathophysiology of ACTH secretion from the tumor. It emphasizes the need for thorough endocrine evaluation in unexplained cardiac and psychiatric presentations. Multidisciplinary management ensured a favorable outcome.