Endocrine Abstracts

Objective

Autonomous cortisol secretion (ACS) is the most common hypersecretion syndrome present in patients diagnosed with adrenal incidentalomas (AI). ACS is associated with various metabolic derangements. Thus far, very few and mostly inconclusive data exists regarding the association between AI’s radiological characteristics and hormonal functionality. In this study we assessed the associations between radiological characteristics of incidentally discovered adrenal findings, ACS, and metabolic abnormalities.

Methods

We prospectively collected data from 77 patients evaluated for adrenal incidentalomas in a large tertiary medical center between December 1^st, 2017 and October 31 ^st, 2020. Post -Dexamethasone suppression test (DST) morning cortisol levels were used to diagnose ACS, and the association between AI’s radiological features, post-DST morning cortisol levels and metabolic outcomes was analyzed.

Results

Maximal adenoma diameter linearly correlated with post-DST morning cortisol levels (R = 0.474, P < 0.01.). This correlation translated to a linear correlation between maximal adrenal adenoma diameter and metabolic parameters, mainly fasting plasma glucose and glycated hemoglobin levels (R = 0.58, P < 0.01 and R = 0.56, P < 0.01, respectively). Moreover, we demonstrate that the linear correlation between maximal adenoma diameter and post -DST cortisol is greatly intensified in patients meeting the criteria for the metabolic syndrome. Additionally, we show that patients with ACS, have larger adrenal adenomas than patients harboring non-functioning adenomas (27 mm, Vs. 20.3 mm, respectively, P < 0.01), and that adenomas sized ≤ 13.9 mm are likely to be non-functional with a sensitivity of 90%.

Conclusions

The diameter of incidentally found adrenal lesions is positively associated with ACS and abnormal glucose homeostasis. Our data suggest that initial adrenal adenoma diameter may be an adjunct for the risk stratification for ACS and its associated metabolic morbidity.