What type of hormonal evaluation is recommended for a patient with an adrenal myelolipoma?

Hormonal Evaluation for Adrenal Myelolipoma

A complete hormonal workup is mandatory for all patients with adrenal myelolipoma, regardless of size or imaging characteristics, as recommended by multiple guidelines. 1

Recommended Hormonal Evaluation

Core Hormonal Tests (Required for All Patients)

1. Cortisol Assessment

   • 1mg overnight dexamethasone suppression test 2, 1
   • Interpretation:
     • <50 nmol/L: excludes autonomous cortisol secretion
     • 51-138 nmol/L: possible autonomous cortisol secretion

     • 138 nmol/L: evidence of autonomous cortisol secretion

2. Catecholamine Screening

   • Plasma free metanephrines or 24-hour urinary metanephrines 2, 1
   • Particularly important for nodules with HU >10 on non-contrast CT
   • Values >2× upper limit of normal are diagnostic

3. Aldosterone Evaluation

   • Aldosterone-to-renin ratio 2, 1
   • Indicated for patients with hypertension and/or hypokalemia
   • Ratio >20 ng/dL per ng/mL/hr has >90% sensitivity/specificity for hyperaldosteronism

Additional Tests (Based on Clinical Suspicion)

1. For Suspected Adrenocortical Carcinoma (ACC) or Virilization
   • Serum DHEAS (dehydroepiandrosterone sulfate) 2, 1
   • Serum testosterone
   • Additional tests if clinically indicated: 17β-estradiol, 17-OH progesterone, androstenedione, 17-OH pregnenolone, 11-deoxycorticosterone, progesterone, and estradiol 2

Clinical Considerations

• Although adrenal myelolipomas are typically non-functioning, cases of hormone-secreting myelolipomas have been reported, including catecholamine-secreting 3 and DHEAS-producing variants 4

• Approximately 10% of adrenal myelolipomas are associated with congenital adrenal hyperplasia, and 7.5% with other adrenal hypersecretory disorders 5

• The hormonal evaluation results determine management approach and surgical considerations:

  • Functional tumors typically require surgical intervention
  • Non-functional myelolipomas <4cm can be managed conservatively 1

Common Pitfalls to Avoid

1. Don't skip hormonal evaluation based on imaging alone

   • Even classic-appearing myelolipomas on imaging can be hormonally active

2. Don't overlook subclinical hormone production

   • Mild autonomous cortisol secretion (MACS) can contribute to metabolic comorbidities without overt Cushing's syndrome 2

3. Don't forget preoperative preparation if surgery is planned

   • Undiagnosed pheochromocytoma can lead to dangerous intraoperative hypertensive crisis
   • Cortisol-producing tumors require perioperative steroid coverage

4. Don't rely on a single test for cortisol assessment

   • The overnight dexamethasone suppression test is the most sensitive initial test, but additional testing may be needed for borderline results 6

By following this comprehensive hormonal evaluation approach, clinicians can accurately determine the functional status of adrenal myelolipomas and guide appropriate management decisions.