Who monitors an adrenal mass?

Monitoring of Adrenal Masses

Adrenal masses require multidisciplinary monitoring involving endocrinologists, surgeons, and radiologists, especially when imaging is not consistent with a benign lesion or there is evidence of hormone hypersecretion. 1

Initial Evaluation and Monitoring Team

The management of adrenal incidentalomas requires a systematic approach with dedicated imaging, comprehensive hormonal evaluation, and risk stratification. The monitoring team typically includes:

• Endocrinologists: Primary specialists for hormonal evaluation and medical management
• Surgeons (Urologists): For surgical intervention when indicated
• Radiologists: For specialized adrenal imaging interpretation
• Primary care physicians: Often involved in initial detection and follow-up

The 2023 Canadian Urological Association (CUA) guideline endorsed by the American Urological Association (AUA) specifically recommends a multidisciplinary review when 2:

• Imaging is not consistent with a benign lesion
• There is evidence of hormone hypersecretion
• The tumor has grown significantly during follow-up
• Adrenal surgery is being considered

Monitoring Protocol

Imaging Surveillance

• Benign-appearing lesions (<10 HU on non-contrast CT, <3 cm, non-functioning):

  • Repeat imaging in 6-12 months
  • No further imaging if stable and <4 cm 1

• Indeterminate lesions:

  • Repeat evaluation after 3-12 months
  • Consider surgery if growth >5 mm/year 1

Hormonal Monitoring

All patients with adrenal masses should undergo:

1. Cortisol assessment: 1mg overnight dexamethasone suppression test

   • <50 nmol/L: Normal
   • 51-138 nmol/L: Possible autonomous cortisol secretion

   • 138 nmol/L: Evidence of autonomous cortisol secretion 1

2. Catecholamine screening: Plasma free metanephrines or 24-hour urinary metanephrines

   • Particularly important for nodules with HU >10 on non-contrast CT 1

3. Aldosterone evaluation: Aldosterone-to-renin ratio for patients with hypertension/hypokalemia

   • Ratio >20 ng/dL per ng/mL/hr has >90% sensitivity/specificity for hyperaldosteronism 1

Special Considerations

Functional Tumors

• Cortisol-secreting adenomas: Monitoring by endocrinologists for metabolic complications
• Aldosterone-secreting adenomas: Monitoring of blood pressure and potassium levels
• Pheochromocytomas: Careful blood pressure monitoring and preoperative preparation if surgery planned 1

Malignant Potential

• Lesions >4 cm with inhomogeneous appearance or HU >20 have higher risk of malignancy and typically require surgical management rather than monitoring 1, 3

Post-Surgical Monitoring

• For patients who undergo adrenalectomy for functional tumors, endocrinologists monitor hormone replacement needs
• For patients with adrenocortical carcinoma, oncologists join the monitoring team for surveillance and potential adjuvant therapy 4

Common Pitfalls in Monitoring

1. Inadequate hormonal evaluation: Even radiologically benign-appearing masses require complete hormonal assessment
2. Inconsistent follow-up: Patients with non-operated masses need structured surveillance
3. Missing mild autonomous cortisol secretion: This condition increases morbidity and mortality risk despite absence of overt Cushing's syndrome 3
4. Failure to recognize growth: Small changes in adrenal mass size may indicate malignant potential

The monitoring approach should be tailored based on imaging characteristics, hormonal status, and patient-specific factors, with clear communication between all specialists involved in the patient's care.