Is the Adrenal Incidentaloma Functionally Active? An Approach-To-The-Patient-Based Review

Abstract

Adrenal incidentalomas are a common occurrence. Most of them are adrenocortical adenomas that do not cause harm and do not require surgery, but a non-negligible proportion of incidentalomas is represented by functionally active masses, including cortisol-secreting adenomas (12%), pheochromocytomas (3-6%), aldosterone-secreting adenomas (2-3%), as well as malignant nodules, such as adrenocortical carcinomas (2-5%), which can be either functioning or non-functioning. All patients with an adrenal incidentaloma should undergo a few biochemical screening and confirmatory tests to exclude the presence of a functionally active mass. In this approach-to-the-patient-based review, we will summarize current recommendations on biochemical evaluation and management of functionally active adrenal incidentalomas. For this purpose, we will present four case vignettes, whereby we will describe how patients were managed, then we will review and discuss additional considerations tied to the diagnostic approach, and conclude with practical aspects of patient perioperative management. To improve the perioperative management of patients with functional adrenal incidentalomas, multidisciplinary meetings are advocated.

Keywords: adrenal incidentaloma; autonomous cortisol secretion; perioperative management; pheochromocytoma; primary aldosteronism; surgery.

Figure 1

Representative images of the case vignettes. (a) CT scan of Case 1: unenhanced CT images show a small lesion with a low attenuation value in the right adrenal gland. (b) CT scan of Case 2: unenhanced CT images show a small lesion with a low attenuation value in the left adrenal gland. (c,d) CT scan and MIBG scintigraphy of Case 3: unenhanced CT image shows a high attenuation lesion in left gland (c) with only adrenal MIBG uptake on subsequent scintigraphy (d). (e,f) CT scan and ¹⁸F-FDG PET CT of Case 4: unenhanced CT image shows a very large inhomogeneous lesion in right gland (e), without extra-adrenal F-FDG uptake on subsequent PET-CT (f).