A puzzling malignant adrenal tumor

A previously healthy 49-year-old male presented with abdominal pain, constitutional syndrome, paroxysmal palpitations and diaphoresis. Full-body CT scan showed a large malignant adrenal mass with abdominal lymph node and pulmonary metastasis. Biochemical studies revealed hypersecretion of catecholamines, cortisol, sexual steroids and steroid precursors; ACTH was not suppressed, and chromogranin A was negative. 18F-fluorodeoxyglucose PET/CT showed intense tracer uptake in the adrenal mass and abdominal lymph nodes. He was placed under adrenergic blockade and offered cytoreductive surgery, but his evolution was unfavorable with rapid clinical deterioration due to compressive abdominal symptoms, uncontrolled pain, peripheral oedema, cachexia and severe dilated cardiomyopathy. 123I-metaiodobenzylguanidine scintigraphy was negative. Poor clinical status precluded any surgical or systemic treatments. A biopsy of the adrenal mass suggested adrenocortical carcinoma. Two weeks later he developed recurrent level 3 non-insulin mediated hypoglycemias, with suppressed levels of insulin, C-peptide, IGF-1 and IGF-BP3. He responded poorly to palliative measures and died within a week, four months after the initial diagnosis. We present a puzzling case of an aggressive stage IV adrenal malignancy with bizarre secretory profile. Although we could not obtain a surgical specimen, combined available data suggested adrenocortical carcinoma. The pathophysiology is uncertain, and we explored exceedingly rare scenarios, including adrenocortical carcinoma masquerading as pseudo-pheochromocytoma; synchronous adrenocortical carcinoma and pheochromocytoma; adrenal mixed corticomedullary tumor; and ACTH-producing pheochromocytoma. The presence of ectopic ACTH-dependent hypercortisolism, discordant plasma and urinary metanephrine levels and IGF-2 mediated hypoglycemias were also quite perplexing. To our knowledge, this is the first report of a malignant adrenal tumor co-secreting steroid hormones with ACTH-dependent hypercortisolism, catecholamines and IGF-2. We faced obvious diagnostic and therapeutic challenges and encourage future studies to explore the complex interactions between cortical and chromaffin cells of the adrenal gland, that may have bidirectionally contributed to this patient's condition.