Organ System Pathology USMLE Step 1 Practice Question
A 63 year old man with a 50 pack year smoking history has new hypertension, proximal weakness, and hyperglycemia. Examination shows thin skin and diffuse hyperpigmentation. Serum ACTH is markedly elevated, and both low dose and high dose dexamethasone fail to suppress cortisol. Chest imaging shows a hilar mass. Which of the following is the most likely diagnosis?
Answer choices
- APrimary hyperaldosteronism
- BAdrenal cortical adenoma
- CPituitary corticotroph adenoma
- DSmall cell lung carcinoma producing ACTHCorrect answer
- EPheochromocytoma
- FEctopic CRH secretion from a carcinoid tumor of the bronchus
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