Adrenal Masses: Differential Dx and Work-up Sara Faber August 4, 2008
Why should we care? • Autopsy studies demonstrate ~9% of people have a 2 mm – 4 cm mass at time of death. • More recent studies have shown that up to 5% of CT scans performed for various reasons reveal adrenal lesions.
Approach to the Adrenal Mass • Functional versus Non-functional? • Malignant versus Benign? • Most masses are nonfunctional and only 1 in 4000 is malignant.
What if there’s suspicion of functionality or malignancy? • Functional tumors: • Adrenal Medullary Tumors: • Pheochromocytoma • Childhood tumors: ganglioneuromas, neuroblastomas • Adrenal Cortical Tumors: • Cortisol-secreting adenoma • Aldosteronoma • Carcinoma • Known history of malignancy • Adrenal glands are common sites of metastasis
Pheochromocytoma • Epi: • Rare: 3-4 diagnoses/million in the US • 25% diagnosed incidentally by imaging • Signs/Symptoms: HTN, tachycardia, palpitations, sweating, HA, tremor • Labwork demonstrates: • Elevated plasma fractionated metanephrines • 24 hour urine: elevated fractionated catecholamines and their metabolites: metanephrines and vanillylmandelic acid (VMA) • For the boards: assoc with AD syndromes MEN I & II; type 1 neurofibromatosis; von Hippel Lindau; Sturge Weber
Cortisol-secreting Adenoma:the sweet part • Epi: F > M; ages 30-50s • Signs/Symptoms: • May lead to clinical or sub-clinical Cushing’s syndrome • Most commonly: obesity, HTN, glucose intolerance or DMII, hypercholesterolemia • Labwork demonstrates: • Failed dex suppression test (cortisol can be monitored with diurnal bloodwork for inpts or saliva for outpts) • Low DHEA-sulfate (increased cortisol suppresses pituitary-adrenal axis) • Elevated 24 hour urinary cortisol
Aldosteronomas:the salty part • Epi: • <1% of incidentalomas, more often L than R • F > M, age 30-40 • Signs/Symptoms: • Most often, patients are not hypoK • Therefore, screen all HTN pts with incidental mass • Labwork reveals: • Increased serum aldosterone • Decreased plasma renin activity
Adrenal Cortical Carcinoma:the sex hormones • Epi: • Rare: 0.02% of cancers, 0.3 cases/million worldwide • F > M; two age peaks: <5yo & 40-50s • Signs/Symptoms: • Androgen excess is most common virilization • Cushing’s syndrome also seen • Labwork demonstrates: • Elevated DHEA-sulfate and androstendedione • Failed dex suppression
So, what to do with adrenal masses? • Previously, histopathology was gold standard • Currently, various imaging techniques are regarded as ideal, due to ease: • CT with or without contrast (83% accurate in diagnosing malignancy) • Chemical shift MRI (94% accurate) • Norcholesterol scintigraphy (92% accurate)
Additional recommendations • Labwork • FOR ALL MASSES: Dex suppression test, plasma-free metanephrines to determine functionality • In HTN pts, measure serum K+ and plasma aldosterone/renin activity • Monitor with physical exam, bloodwork and 2 imaging studies 6 months apart.
Size matters… • NIH recommendation for adrenal masses: • If mass > 6 cm surgery. • If mass < 4 cm monitor (bloodwork and imaging) • If 4-6 cm, decision may be based upon imaging findings and bloodwork results.
References • Song, et al. The Incidental Adrenal Mass on CT: Prevalence of Adrenal Disease in 1,049 Consecutive Adrenal Masses in Patients with No Known Malignancy. AJR 2008; 190: 1163-1168. • Lumachi, et al. High risk of malignancy in patients with incidentally discovered adrenal masses: accuracy of adrenal imaging and image-guided fine needle aspiration cytology. Tumori 2007; 93(3): 269-274. • NIH state-of-the-science statement on management of the clinically inapparent adrenal mass (“incidentaloma”). NIH Consens State Sci Statements 2002; 19(2): 1-25. • Kuruba, et al. Current management of adrenal tumors. Curr Opin in Onc 2008; 20(1): 34-46. • Cotran, et al. Robbins Pathologic Basis of Disease, 6th ed. WB Saunders Company, Philadephia, PA. 1999.