Wednesday, January 05, 2011

Working up adrenal masses

I saw Mrs. R, a pleasant 62 year old woman who was found to have an adrenal mass incidentally when she had a CT abdomen/pelvis for diverticulitis. Her medical history was significant only for hyperlipidemia, hypertension, both well controlled, and knee surgery.
Her right adrenal had a 3.2 cm nodular mass on the medial limb of the gland; this was 15 Hounsfield units pre-contrast, 40 post-contrast, and 22 Hounsfield units on delayed washout images.
When I saw her, the diverticulitis has resolved and she was totally symptom-free.

This case I'm working up reminds me of the conversation I had with someone recently about something similar: someone had the brilliant wisdom to biopsy a pheo before ruling out a pheo. For Mrs. R, on the basis of the radiologic features alone, adrenalectomy is probably indicated; the strong enhancement with IV contrast is worrisome, if nothing else for malignancy. Now, some may say, "She is asymptomatic, and is normotensive and has no spells. No need to screen for pheochromocytoma".

Wrong.

Wrong wrong wrong.

Here's a caveat I picked up from one of my mentors who's one of the world experts on this subject. You ALWAYS have to screen for a pheo in cases of adrenal masses. Even if the patient was asymptomatic, as quite a number of pheochromocytoma patients have no symptoms. And those who do, one of the most common is essential hypertension. In other words, none of the classical spells of uncontrolled hypertension the textbooks talk about. And certainly none of the crap you saw on that episode of House MD.


In Mrs. R's case, I ordered 24-hour urine catecholamines and metanephrines (another teaching point- always look through the medlist and ensure all interfering medications are stopped)- her urine normetanephrines came back at 1100 mcg (3x normal). She's coming in to see me tomorrow to draw serum metanephrines as a confirmatory test and to discuss preparation for surgery. I'd be surprised if this did not turn out to be a pheochromocytoma.

(and even if this isn't, it still needs to be removed)