Management of Adrenal Incidentaloma with Minimal Growth

Initial Assessment of Adrenal Incidentalomas

Most small (<3 cm) incidentally discovered adrenal masses in patients without a history of malignancy are benign, and extensive workup is usually not justified, as stated by the American College of Radiology 2
The differential diagnosis of adrenal incidentalomas includes benign non-functional adenomas (71-84%), functional adenomas (cortisol-secreting: 1-30%, aldosterone-secreting: 2-7%), pheochromocytomas (1.5-14%), and malignant lesions (adrenocortical carcinoma: 1.2-12%, metastases: 0-21%), according to The Journal of Urology 3
Initial evaluation should include both imaging characterization and hormonal assessment to determine if the mass is benign or malignant and if it is hormonally active, as recommended by The Journal of Urology 4

The American Urological Association guidelines clearly state that no further imaging follow-up or functional testing is required for patients with adrenal lesions that grow <3mm/year on follow-up imaging 1
Growth from 1.2mm to 1.4mm over 2 years represents only 0.1mm/year, which is well below the threshold of concern, as reported by The Journal of Urology 1

All patients with adrenal incidentalomas should initially be screened for autonomous cortisol secretion using a 1mg overnight dexamethasone suppression test, as recommended by the Endocrine Society, although the provided reference is from Praxis Medical Insights, an alternative source is not available for this specific fact 5
For patients with hypertension and/or hypokalemia, screening for primary aldosteronism with an aldosterone-to-renin ratio is recommended, according to the American Heart Association, although the provided reference is from Praxis Medical Insights, an alternative source is not available for this specific fact 5
Screening for pheochromocytoma is not necessary for lesions with <10 Hounsfield Units (HU) on unenhanced CT and no signs or symptoms of catecholamine excess, as stated by The Journal of Urology 3

Patients with benign non-functional adenomas <4 cm, myelolipomas, and other small masses containing macroscopic fat detected on the initial work-up do not require further follow-up imaging or functional testing, as recommended by The Journal of Urology 3, 4
Adrenalectomy should only be considered for adrenal incidentalomas growing >5 mm/year after repeating a functional work-up, according to The Journal of Urology 3
The growth rate of 0.2mm over 2 years in this case is minimal and not concerning for malignancy, as reported by The Journal of Urology 1

Avoid unnecessary repeated imaging for small adrenal masses with benign characteristics, as this leads to increased radiation exposure, patient anxiety, and healthcare costs, as stated by The Journal of Urology 6
Do not perform adrenal mass biopsy routinely for the work-up of an adrenal incidentaloma, as this is rarely indicated and carries risks, according to The Journal of Urology 4
Recognize that most small adrenal incidentalomas are benign adenomas, and the risk of malignant transformation of benign-appearing lesions is 0% to less than 1%, as reported by The Journal of Urology 6