Endocrine Abstracts

Introduction: Subclinical Cushing’s syndrome (SCS) occurs in up to 12% of patients with incidentally found adrenal masses. Optimal management remains controversial. We report our experience of nine patients with SCS managed at our institution from 2007 to 2016.

Methods: All patients were referred for adrenal incidentalomas (AI) and had no discriminatory clinical features of Cushing’s syndrome. SCS was defined using cortisol levels > 138 nmol/l after overnight 1-mg dexamethasone suppression test and one additional abnormal biochemical test. ACTH was suppressed in all. Urinary free cortisol measurements were normal in the majority.

Patients and results: The median age of our patients was 53 years (range 36–63) and all but one were female. Mean size of the adenomas was 2.65+0.52 cm. Majority of our patients had metabolic comorbidities of overweight, hypertension, glucose intolerance or diabetes and dyslipidemia. One patient initially followed up as a non-functioning AI developed SCS over 8 years of surveillance as her adenoma grew. Another patient had bilateral adrenal adenomas. All our patients underwent surgical resection. The patient with bilateral nodules underwent bilateral subtotal adrenalectomy. All but one required a period of postoperative corticosteroid support. Following withdrawal of steroids, there was observable median weight loss of 3.85 kg (0.5–10.7) compared to presurgical weight. Four patients had an improvement of their BMI category from overweight to normal. All six patients with hypertension had sustained improvement in their blood pressure: two became normotensive and the remainder had reduction of doses of antihypertensives. However there was no change to glycemic and lipid status.

Conclusions: In our small series of patients with SCS, surgical intervention resulted in improved metabolic outcomes. We therefore suggest that if patients are surgically fit, surgery should be considered for SCS.