A 48-year-old woman has incidentally found a 2.5 cm left adrenal nodule on CT. CT shows Hounsfield units of 8 on unenhanced scan. She is normotensive, has no Cushingoid features. Overnight 1 mg dexamethasone suppression test shows cortisol of 4.2 μg/dL (normal <1.8 μg/dL). DHEAS is mildly low. Urinary metanephrines are normal. How should she be managed?
- A Immediate laparoscopic adrenalectomy
- B MRI adrenal to further characterise the lesion
- C Repeat CT in 3 months then annual for 5 years
- D Mild autonomous cortisol secretion (MACS) — counselling for comorbidities, consider surgery if comorbidities worsen ✓
Explanation
This patient has an adrenal incidentaloma with Hounsfield units <10 (consistent with lipid-rich adenoma) and post-dexamethasone cortisol of 4.2 μg/dL — exceeding the 1.8 μg/dL cutoff but below the 5 μg/dL threshold for overt Cushing syndrome, meeting the current ESE/ENSAT 2023 criteria for Mild Autonomous Cortisol Secretion (MACS, formerly non-functional adenoma with subtle hypercortisolism). The ESE 2023 clinical practice guidelines recommend counselling for metabolic comorbidities (hypertension, diabetes, osteoporosis) and considering laparoscopic adrenalectomy only if comorbidities are present and attributable to MACS.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.