Adrenal Adenoma

Unilateral non-functional adrenal adenoma with imaging features consistent with a benign lesion

Discharge Criteria:

1. Structural
   1. Imaging characteristics of adrenal lesion are clearly in keeping with a benign etiology
      1. Size < 4cm
      2. HU < 10 on unenhanced CT/non-contrast phase
      3. Imaging criteria is consistent with a myelolipoma (with macroscopic fat)
   2. No growth on follow-up imaging at 6-12 months (< 5mm in greatest diameter)
      1. If size > 2cm and younger individual (< 40 years), consider another scan at 24 months
   3. No history of germline disease associated with ACC, pheochromocytoma or adrenal adenoma (i.e. family history of hereditary adrenal disease, < 40 years, and bilateral nodules)
2. Baseline Hormonal Assessment
   1. Plasma/urine metanephrine negative if CT HU >= 10
   2. Aldosterone: Renin Ratio (ARR) < screening threshold (lab assay dependent) if patient has HTN or hypokalemia
   3. Cortisol < 50mmol/L on 1mg overnight dexamethasone suppression test

Resources:

• Letter to primary care provider
• Letter to patient

Topic Expert Review: Jeannette Goguen (Endocrinologist), Kenneh Pace (Urologist), Jessie Pasternak (Urologist)

Primary Care review: Dr Curtis Handford, DFCM, St Michael's Hospital

Plain language review: Katrina Grieve, St Michael's Hospital

References:

1. Fassnacht et al, European Society of Endocrinology clinical practice guidelines on the management of adrenal incidentalomas, in collaboration with the European Network for the Study of Adrenal Tumors, European Journal of Endocrinology, Volume 189, Issue 1, July 2023, Pages G1–G42, https://doi.org/10.1093/ejendo/lvad066

2. Rowe NE, Kumar RM, Schieda N, et al. Canadian Urological Association guideline: Diagnosis, management, and followup of the incidentally discovered adrenal mass. Can Urol Assoc J 2023;17(2):12-24. http://dx.doi.org/10.5489/cuaj.8248