Adrenal Incidentalomas: Effect of Size on Cortisol Secretion and Clinical Features

Purpose: The aim of this study was to assess the relationship between adrenal incidentaloma size, cortisol secretion suppressibility by Dexamethasone and relevant clinical and laboratory parameters. Methods: This retrospective study included all patients diagnosed with adrenal incidentaloma and admitted to the single department of the Clinic of endocrinology, Diabetes and Diseases of Metabolism during the period from 2012 till the end of 2019. The inclusion criterion was the presence of an asymptomatic adrenal mass on imaging not performed for suspected adrenal disease. The study group included 197 subjects. Adrenal masses were detected using CT or NMR scan. We analysed the correlation between tumour size and relevant hormonal and clinical parameters. Results: We found a significant positive correlation between incidentaloma size and morning cortisol, cortisol after overnight Dexamethasone, and a significant negative correlation between incidentaloma size and morning ACTH, and hip T score. Also, there was a weak but statistically significant correlation between incidentaloma size and systolic blood pressure. Conclusions: Our study shows that the prevalence of adrenal autonomous cortisol secretion increases with incidentaloma size, and that prevalence of hypertension and osteoporosis also increases with an increase of incidentaloma size.