Endocrine Abstracts

Purpose

To evaluate the prevalence of bilateral macronodular adrenal hyperplasia (BMAH) in patients with adrenal incidentalomas (AIs) and analyse the differential phenotype of patients with BMAH compared to other bilateral adrenal lesions which do not meet BMAH definition (non-BMAH), with associated possible or confirmed autonomous cortisol secretion (ACS).

Methods

Retrospective study of patients with AIs diagnosed between 2013 and 2019 in the Hospital Ramón y Cajal (n = 730). Patients with bilateral disease and associated possible or confirmed ACS were included (n = 98). Possible ACS was defined as a DST > 1.8 µg/dl without specific clinical signs of Cushing syndrome, and confirmed ACS when cortisol post-DST was > 5.0 µg/dl. BMAH diagnosis was established in patients with hyperplasia and bilateral adrenal nodules > 1 cm and associated possible or confirmed ACS.

Results

Inclusion criteria were fulfilled by 98 out of the 730 patients with AIs included in the RCUH ADRENAL INCIDENTALOMA database. BMAH was confirmed in 31 patients (4.2% of AIs and 31.6% of bilateral AIs with possible or confirmed ACS). Patients with BMAH presented a higher prevalence of ACS (OR 4.1, 95% CI 1.38 to 12.09, P = 0.010), but differences disappeared after adjusting by tumor size and total adenomatous mass (adjusted OR 2.3, 95% CI = 0.65–8.27, and OR 2.3, 95% CI 0.47 to 11.21, respectively). However, no significant differences in the cardiometabolic profile of both groups were observed. Tumor size and total adenomatous mass were significantly higher in patients with BMAH (30.2 ± 12.16 vs 24.3 ± 8.47, P = 0.010 and 53.9 ± 20.8 vs 43.3 ± 14.62, P = 0.023). After a median follow-up of 33.7 (range 3.7 to 194.8) months, no differences in the risk of developing comorbidities was observed between BMAH and non-BMAH. Aberrant receptors study was performed in 5 patients with BMAH, being positive in three patients (in the metoclopramide test in two patients and in the metoclopramide and mixed food test in another). Two patients with BMAH underwent unilateral adrenalectomy, with improved of cardiometabolic and hormonal alterations, one patient (study positive for mixed food test) was treated with lanreotide with no response and other (one of the patients with a positive metoclopramide test) with amitriptyline, without response neither.

Conclusion

BMAH is relatively common in patients with incidentally detected bilateral adrenals lesions with associated subclinical hypercortisolism. The higher prevalence of ACS in BMAH compared to non-BMAH is related with the higher tumor size and total adenomatous mass in patients with BMHA, but no differences in the cardiometabolic profile was observed between both groups.