Endocrine Abstracts

Background: Adrenal incidentalomas (AI) are asymptomatic adrenal lesions found on imaging not primarily performed to detect adrenal disease. We conducted a retrospective audit of management of AI following European Society of Endocrinology recommendation (2016).

Methods: This was a retrospective review of incidentaloma referrals over 9 months (June 2017–March 2018). Cases were identified using criterion search of the referral console. Additional data collected from clinic letters and investigation results.

Results: Sixty-three cases were identified. Fourteen were excluded (12 pending, 1 not incidentaloma, and 1 declined follow-up). From 49 remaining cases, 25 (51%) were females, with mean age of 63 years (range 33–90). The mean lesion size was 2.5 cm (range 0.8–6 cm) and 30 (61%) were characterised as adenoma on imaging. For Cushing’s workup, 39 (80%) had overnight dexamethasone suppression testing (ODST), 5 (10%) 24 h urinary free cortisol, 1 (2%) low dose dexamethasone suppression testing (LDDST), 4 (8%) missing (1 lung metastasis, 1 deemed low risk, 2 unknown). 16 (33%) failed ODST (2 were deemed to be non-functional and remaining 14 underwent LDDST). LDDST revealed 3 (6%) normal, 4 (8%) adrenal Cushing’s and 7 (14%) probable autonomous cortisol secretion. For Phaeochromocytoma workup, 44 (90%) had urine/plasma metanepharine levels checked, 5 (10%) missing (1 deemed low risk, 4 requested, but not carried out). 3 (6%) cases of Pheochromocytoma were identified. For Conn’s workup, 44 (90%) had plasma renin and aldosterone checked, 5 (10%) missing (3 deemed low risk, 1 sample lost, 1 lung metastasis). 1 (2%) case of Conn’s adenoma identified. 8 (16%) have been referred for surgery (4 Cushing’s, 3 Phaeochromocytoma and 1 metastatic disease).

Conclusion: The use of pre-clinic investigation protocol facilitated our adherence to the guideline. Incidence of functional tumours was similar to the literature justifying investigational approach. ODST demonstrated reasonable specificity of 69% minimising need for LDDST.