Diabetes Mellitus USMLE Step 1 Practice Question
A 62 year old man with a long smoking history presents with new onset diabetes, proximal muscle weakness, hypokalemic metabolic alkalosis, and diffuse hyperpigmentation. Cortisol is very high, ACTH is very high, and there is no suppression with high dose dexamethasone. Which of the following is the most likely source of excess ACTH?
Answer choices
- APituitary microadenoma
- BThyroid medullary carcinoma
- CPheochromocytoma
- DAdrenal adenoma
- ESmall cell carcinoma of the lungCorrect answer
- FPancreatic neuroendocrine tumor
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