Management of 2.2 x 2.6 cm Right Adrenal Adenoma with Liver Cysts
This patient requires hormonal evaluation to exclude functional tumors, and if non-functional and confirmed benign on imaging, no further follow-up imaging or functional testing is needed. 1
Immediate Next Steps: Hormonal Workup
The radiologic diagnosis of "adrenal adenoma" based on low density and exophytic appearance is presumptive but requires confirmation through both hormonal testing and imaging characterization, as approximately 5% of radiologically benign incidentalomas harbor subclinical hormone production requiring treatment. 2, 3
Required hormonal screening includes: 1, 2, 4
- 1 mg overnight dexamethasone suppression test to screen for autonomous cortisol secretion (mild autonomous cortisol secretion/MACS)
- Plasma metanephrines or 24-hour urinary metanephrines to exclude pheochromocytoma (critical to prevent hypertensive crisis)
- Aldosterone-to-renin ratio only if the patient has hypertension and/or hypokalemia
Imaging Characterization
Since this was an unenhanced CT, you must verify the Hounsfield unit (HU) measurement of this lesion. 1, 2
If HU ≤10: The mass is definitively a benign lipid-rich adenoma with 100% specificity. 1, 2, 5 No further imaging is required. 1, 2
If HU >10: Second-line imaging with either contrast-enhanced washout CT or chemical shift MRI is required to confirm benign characteristics. 1 For washout CT, >60% absolute washout at 15 minutes indicates benign adenoma with sensitivity >95% and specificity >97%. 1 However, be aware that approximately one-third of pheochromocytomas may washout in the adenoma range, and one-third of adenomas may not washout adequately—this is why hormonal screening cannot be skipped. 1
Management Algorithm Based on Results
If Non-Functional and Benign Imaging (HU ≤10):
No further follow-up imaging or functional testing is required. 1, 2, 3 This recommendation is based on moderate-quality evidence showing 0% to <1% risk of malignant transformation in benign non-functional adenomas <4 cm. 2
If Functional Abnormality Detected:
- Pheochromocytoma or aldosterone-secreting adenoma: Adrenalectomy is indicated, preferably via minimally invasive surgery. 1
- Mild autonomous cortisol secretion (MACS): Adrenalectomy should be considered only in younger patients with progressive metabolic comorbidities (diabetes, hypertension, osteoporosis) attributable to cortisol excess after shared decision-making. 1, 2 Patients not managed surgically require annual clinical screening for new or worsening metabolic comorbidities. 1
If Indeterminate After Second-Line Imaging:
Shared decision-making between patient and clinician should guide management, with options including repeat imaging in 3-6 months versus surgical resection. 1
Liver Cysts Management
The multiple liver cysts described are simple hepatic cysts, which are benign and extremely common (present in 2.5-18% of the population). [@General Medicine Knowledge@] These require no further evaluation or follow-up unless symptomatic. The 1 mm hypodensity that is "too small to accurately characterize" is clinically insignificant and does not warrant further investigation.
Critical Pitfalls to Avoid
Never perform adrenal biopsy for this incidentaloma—it is rarely indicated, carries unnecessary risks including potential tumor seeding, and most importantly, pheochromocytoma must be excluded before any biopsy attempt to prevent life-threatening hypertensive crisis. 1, 2, 3
Do not skip hormonal evaluation even though the imaging suggests benign adenoma—functional abnormalities occur in approximately 5% of radiologically benign lesions and require treatment. 2, 3, 4
Avoid unnecessary repeated imaging if the lesion is confirmed benign (<10 HU), non-functional, and <4 cm, as this leads to increased radiation exposure, patient anxiety, and healthcare costs without clinical benefit. 2, 3
Be aware of size threshold: At 2.2 x 2.6 cm, this lesion is well below the 4 cm threshold that would trigger surveillance imaging. 1 Lesions ≥4 cm require repeat imaging at 6-12 months even if benign-appearing, due to higher malignancy risk. 3