Adrenal Disorders USMLE Step 1 Practice Question
A 58-year-old man with a 2-pack-per-day smoking history presents with profound muscle weakness, hypertension, and marked hypokalemia (K+ 2.8 mEq/L). His cortisol is 28 μg/dL and does not suppress with 8 mg dexamethasone overnight. ACTH is 210 pg/mL (markedly elevated). Chest X-ray shows a 3 cm central lung mass. Which of the following is the most likely diagnosis?
Answer choices
- AEctopic ACTH syndrome from small cell lung cancerCorrect answer
- BPrimary hyperaldosteronism with secondary Cushing features
- CAdrenocortical carcinoma
- DPituitary-dependent Cushing disease
- EACTH-secreting bronchial carcinoid tumor
- FEctopic corticotropin-releasing hormone (CRH) syndrome from pulmonary hamartoma
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