Endocrine Abstracts

Aims: We investigated the clinical characteristics and follow-up findings of subjects with adrenal incidentalomas (AI) in a single, tertiary-care hospital in Yekaterinburg, Russia.

Methods: This study retrospectively evaluated consecutive patients aged 18 years or older with benign AI, not treated with adrenalectomy, which were non--functioning (n-56). The initial and follow up evaluation, including clinical assessment, hormonal investigations and imaging were coordinated via a clinic No. 40 in Yekaterinburg.

Results: The median age in patients with nonfunctional adrenal adenomas (NFAI) was 64.41 ± 10.62 years old, women – 46 (82.1%), men – 10 (17.9%). The localization of NFAI in the right adrenal gland is – 14 (25%), in the left – 28 (50%), bilaterally – 14 (25%). The plasma cortisol was 462.35 ± 263.31 nmol/l (101.2 – 535.7 nmol/l); plasma aldosterone –140.21 ± 96.10 pg/ml (25 – 315 pg/ml), urinary fractionated methanephrins (MN) – 131.34 ± 112.73 µg/day (<320 µg/day), urinary fractionated normetanephrins (NM) – 183.86 ± 312.14 µg/day (<390 µg/day ). The mean nodule size of NFAI based on computed tomography was 2.44 ± 1.45 cm, the observation period was 5.27 ± 3.05 years. According to CT, the density of formations in the native phase (NP) varied from −69 to +50 HU, median = 6 ± 26 HU, in arterial phase (AP) median = 72 ± 24 HU, in venous phase (VP) median = 55 ± 23 HU, in delayed (DP) (6 min) median = 27 ± 11 HU.

Conclusion: Most AIs are hormonally inactive adenomas. The low tumor density on CT scan picture may be predictive of both hormonal activity and the risk of malignancy. The risk of malignancy decreases with the size above 2.44 cm.

Keywords: adrenal incidentaloma, nonfunctional adrenal adenoma.