Incidental adrenal mass (adults)
Found on CT or MRI done for another reason. Work up masses of 1 cm or more, or any size with signs of hormone excess.
All Pathways
RadiologyDiagnostic
Incidental Adrenal Mass Evaluation (Adults)
Incidental Adrenal Mass Evaluation (Adults): Incidental adrenal mass (adults) → No adrenal biopsy until phaeochromocytoma is excluded → Under 40, pregna...
Pathway Overview
17 steps
Algorithm Steps
17 total
01Start 02Warning No adrenal biopsy until phaeochromocytoma is excluded
Measure metanephrines first. Biopsy of a phaeochromocytoma can cause a hypertensive crisis.
- No known extra-adrenal cancer: do not biopsy (possible adrenocortical carcinoma)
- Biopsy only via MDT, and only if the result changes management
- Raised metanephrines: alpha-blockade before surgery. No beta-blocker until alpha-blocked
03Warning Under 40, pregnant, child or adolescent: urgent specialist assessment
Higher risk of malignancy and hormone excess.
- Children, adolescents and pregnancy: MRI rather than CT
- Indeterminate mass in these groups: surgery is usually advised
04Action Clinical and hormonal work-up (all patients)
Look for signs of cortisol, aldosterone, catecholamine or androgen excess. Ask about glucocorticoid use by any route (oral, inhaled, topical, injected) before testing. Do this alongside imaging.
- 1 mg overnight dexamethasone suppression test: cortisol 50 nmol/L or less excludes autonomous cortisol secretion. False positives: oral oestrogen, pregnancy, enzyme-inducing drugs (carbamazepine, phenytoin, rifampicin)
- Plasma free or urine fractionated metanephrines if the mass is not clearly a benign adenoma (more than 10 HU or heterogeneous)
- Aldosterone/renin ratio (with potassium) if hypertension or unexplained low potassium. Blood pressure drugs change the result, most of all spironolactone or eplerenone
- Sex steroids and precursors if adrenocortical carcinoma is suspected
- Frail, limited life expectancy: keep tests in proportion to possible benefit (dexamethasone test may not be needed)
05Decision Non-contrast CT: homogeneous and 10 HU or less?
Unenhanced attenuation. Do a non-contrast CT first if not yet done.
- If Yes
- 10 HU or less, homogeneous
06Action Homogeneous, 10 HU or less: benign adenoma
No further imaging, whatever the size. No surgery for a non-functioning benign mass.
- Act on the hormone results (next step)
07Decision Hormone excess on work-up?
Includes raised metanephrines, primary aldosteronism, or cortisol above 50 nmol/L after dexamethasone. Oral oestrogen, pregnancy or enzyme-inducing drugs can give a false-positive result: repeat the test.
- If Yes
- Hormone excess
08Action Hormone excess: endocrinology and adrenal MDT
Raised metanephrines: manage as phaeochromocytoma. No biopsy. Alpha-blockade before any surgery. Cortisol above 50 nmol/L after dexamethasone: stress-dose steroid cover for adrenalectomy, then endocrinology follow-up until the adrenal axis recovers.
- Unilateral tumour with clinically significant hormone excess: adrenalectomy is standard
- Primary aldosteronism: endocrinologist. Adrenal vein sampling before adrenalectomy; suppression test if needed
- Mild autonomous cortisol secretion (cortisol above 50 nmol/L): repeat test, confirm ACTH-independent; surgery case by case
- Mild autonomous cortisol secretion: screen for hypertension, type 2 diabetes and vertebral fractures; not operated: review these every year
09Outcome Adrenal MDT review
Radiologist, endocrinologist and adrenal surgeon. Plan surgery, more imaging or follow-up.
If No- No hormone excess
10End Benign, non-functioning: no follow-up needed
No repeat imaging. No repeat hormone tests unless new signs of hormone excess or comorbidities worsen.
If No- Over 10 HU or heterogeneous
11Decision Not benign on CT: known extra-adrenal cancer?
More than 10 HU or heterogeneous.
- If Yes
- Known cancer
12Action Known cancer, indeterminate mass: exclude phaeochromocytoma first
Measure metanephrines even if a metastasis is likely. Bilateral metastases: check for adrenal insufficiency.
- FDG-PET/CT: strong uptake suggests metastasis
- If the result changes management: FDG-PET/CT, surgery or biopsy (MDT)
- Biopsy only if hormonally inactive, not benign on imaging, and histology changes management
- If it does not change management: image at the same interval as the cancer follow-up
- Path rejoins step 09Shared downstream outcome
If No- No cancer history
13Decision No cancer history: which imaging group?
Group by size, attenuation (HU) and appearance.
- Homogeneous, 11-20 HU, <4 cm
14Action Homogeneous, 11-20 HU, under 4 cm: more imaging now or at 12 months
Only if no significant hormone excess (hormone excess: adrenal MDT). Low risk of malignancy.
- Now: washout CT, chemical-shift MRI or FDG-PET/CT
- Or: non-contrast CT or MRI in 12 months
- Washout CT: relative washout over 58% supports adenoma. Older cut-offs (absolute 60%, relative 40%) miss some cancers
- Benign on extra imaging: no follow-up. Suspicious: adrenal MDT. Still indeterminate, not operated: repeat in 6-12 months
15Action Indeterminate mass, not operated: repeat imaging
One repeat non-contrast CT or MRI at 6-12 months.
- No growth: no further imaging
- Growth more than 20% and at least 5 mm: surgery (MDT)
- Smaller growth: consider another scan in 6-12 months
- Path rejoins step 09Shared downstream outcome
- >=4 cm and heterogeneous or >20 HU
16Action 4 cm or more and heterogeneous or over 20 HU: possible malignancy
Adrenal MDT. Surgery is usually the choice. No biopsy.
- Stage first: chest CT and/or FDG-PET/CT
- Metanephrines before surgery. Raised: alpha-blockade first
- Sex steroids and precursors (possible adrenocortical carcinoma)
- Not operated: repeat imaging in 6-12 months
- Path rejoins step 09Shared downstream outcome
- Other indeterminate
17Action Other indeterminate masses: adrenal MDT, individual plan
For example: 4 cm or more with 11-20 HU; under 4 cm with over 20 HU or heterogeneous. Malignancy is still unlikely.
- Usually more imaging now. Homogeneous: washout CT, chemical-shift MRI or FDG-PET/CT
- Heterogeneous: not washout CT or MRI (not valid). Consider FDG-PET/CT
- Still indeterminate and not operated: repeat imaging in 6-12 months
- Path rejoins step 09Shared downstream outcome
- Not operated
- Path rejoins step 15Shared downstream outcome
Guideline Source
European Society of Endocrinology clinical practice guidelines on the management of adrenal incidentalomas (ESE/ENSAT 2023)
Clinical Safety Information
Clinical Decision Support — Not a Substitute for Clinical Judgment
Individual patient factors may require deviation from these recommendations.
Known Limitations
- Adults with a mass of 1 cm or more. Under 40, pregnancy and children need urgent specialist assessment (MRI rather than CT in pregnancy and children).
- Bilateral masses: assess each mass the same way; specialist input needed (17-hydroxyprogesterone if bilateral hyperplasia).
- Imaging thresholds follow ESE/ENSAT 2023; ACR (2017 white paper, 2021 Appropriateness Criteria) uses 1-2 cm, 2-4 cm and 4 cm size bands.
- Frail patients with limited life expectancy may not need the dexamethasone suppression test.
- Does not cover management of confirmed hormone excess or adrenal cancer in detail.
Contraindicated Populations
Children and adolescents (specialist assessment)Pregnancy (specialist assessment; MRI rather than CT)
Applicable Regions
USAUUKEU
AU: Cortisol after dexamethasone is reported in nmol/L (cut-off 50 nmol/L = 1.8 microg/dL).
EU: ESE/ENSAT 2023 guideline is the primary source.
US: ACR Incidental Findings white paper (2017) and ACR Appropriateness Criteria Adrenal Mass Evaluation (2021) are the radiology references.
Version 2Next review: 2027-09-30
Next steps
Finish the workflow by opening the most relevant calculator, then convert the session into a live account when you are ready.
Related Resources
Frequently Asked Questions
What is the Incidental Adrenal Mass Evaluation (Adults)?
The Incidental Adrenal Mass Evaluation (Adults) is a diagnostic clinical algorithm for Radiology. It provides a structured decision tree to guide clinical decision-making, based on European Society of Endocrinology clinical practice guidelines on the management of adrenal incidentalomas (ESE/ENSAT 2023).
What guideline is the Incidental Adrenal Mass Evaluation (Adults) based on?
This algorithm is based on European Society of Endocrinology clinical practice guidelines on the management of adrenal incidentalomas (ESE/ENSAT 2023) (DOI: 10.1093/ejendo/lvad066).
What are the limitations of the Incidental Adrenal Mass Evaluation (Adults)?
Known limitations include: Adults with a mass of 1 cm or more. Under 40, pregnancy and children need urgent specialist assessment (MRI rather than CT in pregnancy and children).; Bilateral masses: assess each mass the same way; specialist input needed (17-hydroxyprogesterone if bilateral hyperplasia).; Imaging thresholds follow ESE/ENSAT 2023; ACR (2017 white paper, 2021 Appropriateness Criteria) uses 1-2 cm, 2-4 cm and 4 cm size bands.; Frail patients with limited life expectancy may not need the dexamethasone suppression test.; Does not cover management of confirmed hormone excess or adrenal cancer in detail.. Individual patient factors may require deviation from these recommendations.
Get AI-Powered Analysis Alongside This Algorithm
In AttendMe.ai, the Incidental Adrenal Mass Evaluation (Adults) appears automatically when your clinical question matches — alongside evidence from 3M+ peer-reviewed articles.
Try AttendMe Free