Endocrine Abstracts

Although the prevalence of subclinical hypercortisolism (SH) in unilateral incidentalomas (UI) has been extensively reported, patients with bilateral incidentalomas (BI) have not been thoroughly investigated. Moreover, the management of BI poses great dilemmas if surgery is considered, since bilateral adrenalectomy leads to life-long replacement. In the present study, we aimed to describe the characteristics of patients with BI in comparison to their unilateral counterparts. We also report the surgical outcome in a small number of such patients.

Methods: Measurement of morning cortisol (F), ACTH, DHEA-S, midnight F, 24-h urinary free cortisol (UFC), F-post low-dose dexamethasone suppression test (LDDST), fasting glucose/insulin and OGTT in 172 patients with adrenal incidentalomas (AI) (41 with BI). SH was defined as F-post-LDDST>2.5 μg/dl) and one more HPA axis abnormality.

Results: There was no difference in age, BMI, prevalence of diabetes mellitus and IGT between patients with UI and those with BI. UI were significantly smaller (2.3±1.1 cm vs 3.8±1.2 cm, P<0.001). Patients with BI had significantly higher F-post-LDDST (4.3±4.1 vs 2.0±2.6, P<0.001) and lower DHEA-S levels (59.4±55.5 vs 92.4±84.2, P=0.003) but similar levels of UFC, ACTH and midnight F compared to UI. SH was significantly more prevalent in BI (41.5 vs 12.2%, P<0.001). The size of the AI correlated positively with F-post-LDDST (r=0.44, P<0.001) and negatively with ACTH (r=−0.21, P=0.007) and DHEA-S (r=−0.34, P<0.001). Fourteen patients with BI were operated; two underwent total bilateral adrenalectomy, ten unilateral adrenalectomy (largest lesion) and two had unilateral and cortical-sparing contralateral adrenalectomy. Patients who had unilateral adrenalectomy showed significant improvement of SH. Patients who underwent unilateral and cortical-sparing contralateral adrenalectomy showed complete remission of SH.

Conclusions: SH is significantly more prevalent in patients with BI. Its optimum management remains debatable; if surgery is decided an approach aiming to preserve adrenocortical function seems more sensible.