Biochemical investigation of an adrenal incidentaloma
The presence of adrenal incidentalomas has been shown in autopsy studies to occur in about 6% cases and this is mirrored by CT series (Young 2007). The majority of these tumours are silent and express subtle forms of hypercortisolism. However, since most adrenal nodule morbidity is related to hormonal hypersecretion or malignancy, a degree of evaluation is necessary to ascertain if there is:
- unsuspected overt hormonal hypersecretion or
- to identify subtle hormonal hypersecretion,
- to exclude primary or secondary adrenal malignancy (imaging and/or fine needle biopsy).
- Screening tests for cortisol hypersecretion by 24 h UFC and low dose dexamethasone suppression test.
- Screening for phaeochromocytoma
- Screening for hyperaldosteronism
- Screening for excess androgen secretion
No patient preparation is required
- 2 x 24 hour urine containers (acidified for catecholamines and plain for cortisol)
- 1 mg dexamethasone
- 1 plain blood tube (for cortisol)
- 2 Li heparin blood tube (for renin-aldosterone, testosterone & DHEAS)
24 hour urine collection for cortisol (plain container)
during the day take a random blood sample for:
- plasma renin activity and aldosterone in Li heparin tube (5 mL) Do not collect on ice.
- testosterone and DHEAS
24 hour urine collection for catecholamines (acidified container)
The patient takes 1 mg Dexamethasone orally between 2200-2400 and the following morning at 0900h a blood sample (3 mL plain blood) is taken for plasma cortisol.
See individual tests
Sensitivity and Specificity
See individual tests
- Osella G, Terzolo M, Borretta G, Magro G, Ali A, Piovesan A, Paccotti P, Angeli A. Endocrine evaluation of incidentally discovered adrenal masses (incidentalomas). J Clin Endocrinol Metab 1994;79:1532-1539.
Terzolo M, Bovio S, Pia A, Reimondo G, Angeli A. Management of adrenal incidentaloma. Best Prac Res Clin Endocrinol Metab 2009;23:233-243.
- Tsagarakis A. The management of adrenal incidentalomas. In: Grossman A (ed). Clinical Endocrinology. Blackwells Science, Oxford. 2nd edit 1998:484-493.
- Young WF Jr. The Incidentally Discovered Adrenal Mass. NEJM 2007;356:601-610.
JHB 20 Aug 2009