Endocrine Abstracts

Adrenal incidentaloma’s are a common clinical dilemma with increasing utilisation of cross-sectional imaging modalities. The aims of management include i) exclusion of possible malignancy and ii) identification of hormonally active lesions. Our unit has adopted AACE guidelines, including a screen for adrenal androgen hypersecretion. This audit aimed to review the utility of such an approach. We identified case notes of 100 consecutive adrenal incidentaloma’s referred to endocrinology prior to November 2014. All were subject to radiological scrutiny by a dedicated radiologist, whilst endocrine investigations, including two 24 h urinary metanephrines, 1 mg overnight dexamethasone suppression test, renin:aldosterone ratio and DHEAS were arranged, together with electrolytes and blood pressure. Radiologically, 84% were considered to be benign adrenal adenomas on the basis of either CT density (<10 HU), CT contrast washout at 10 min (>60%) or in and out of phase MRI. 3% were myolipomas and 4% phaeochromocytomas. 8% were indeterminate and referred for further investigation or surgery. From a functional perspective, we identified four phaeochromocytomas, all of whom had imaging studies inconsistent with a benign adenoma and raised urinary metanephrines. Five had a 0900 h cortisol of >100 following 1 mg dexamethasone, none of whom had symptoms/signs consistent with cortisol excess and two of whom have already had cortisol excess excluded by further investigation. The remainder have further investigations pending. Two males had elevated DHEAS levels and both had abnormal imaging, one of which proved to be a phaeochromocytoma. There were no abnormal renin:aldosterone ratios. 89% of the cohort was hormonally inactive. On the basis of this audit, we are concerned that adrenal incidentalomas are currently over-investigated. In patients with no symptoms/signs of an underlying endocrinopathy, normal blood pressure, normokalaemia and imaging consistent with a benign adenoma, universal endocrine investigation is largely unrewarding.