Endocrine Abstracts

Background: The increased frequency and quality of abdominal imaging in recent years has led to a dramatic increase in the number of adrenal masses being discovered. This led to the setting up of an adrenal multi-disciplinary team (MDT) and the development of a pathway for managing patients with an adrenal ‘incidentaloma’. We investigated for evidence of hormonal activity in many of these patients.

Method: A retrospective audit was carried out from the notes of all patients with ‘incidentaloma’ referred to the adrenal MDT during an eight-month period. Where clinically indicated, for incidentalomas ≥1 cm diameter, investigations for adrenaline, cortisol and/or aldosterone secretion were performed.

Results: Of 38 patients referred to the MDT 9 patients received no further investigation (typically because the lesion was <1 cm diameter or co-morbid conditions precluded the need for investigation).

One of 29 patients investigated had biochemical evidence of phaeochromocytoma (24 h Urinary metadrenaline=36 μmol/d, (normal range=0–1.4 μmol/d)). A second patient had normal urinary free catecholamines but subsequently proven histological phaeochromocytoma. One of 6 patients investigated had biochemical evidence of Conn’s syndrome (Aldosterone:Renin ratio >149 ng/mU). None of 13 patients investigated had biochemical evidence of Cushing’s syndrome.

Eight patients underwent adrenalectomy. One patient with biochemical phaeochromocytoma was considered too frail for surgery (tumour diameter 4.5 cm).

Post-operative histological examination revealed:

Two cases of benign adrenal cortical adenoma (diameters 4 and 3 cm)

One phaeochromocytoma (diameter 5.2 cm)

One aldosterone-secreting adenoma (diameter 1.2 cm)

One adrenal haematoma (diameter 8.2 cm)

One necrotic inflammatory benign mass (diameter 6.5 cm)

One invasive renal cell cancer (no size given)

One metastatic tumour deposit from lung carcinoma (9 cm)

Conclusions: Our study confirms that adrenal incidentalomas are frequently hormonally active and this does not correlate to tumour size. It is essential to thoroughly investigate all patients for phaeochromocytoma who may subsequently undergo surgery.