Adrenal Incidentaloma
Referral Pathway
A practical pathway for the initial assessment, investigation and referral of patients with an incidentally detected adrenal lesion.
Two questions need to be answered.
Is the lesion hormonally active, and does its imaging appearance raise concern for malignancy?
Could the lesion be functioning?
- Hypertension or unexplained hypokalaemia
- Diabetes, central weight gain or proximal weakness
- Episodic headache, palpitations, sweating or labile blood pressure
- Features of androgen or oestrogen excess
Could the lesion be malignant?
- Large or enlarging lesion
- Heterogeneous or irregular appearance
- High unenhanced CT attenuation
- Local invasion or suspicious lymph nodes
- Known extra-adrenal malignancy
Hormonal and imaging assessment.
Testing should be interpreted alongside the patient’s medications, comorbidities and clinical presentation.
1 mg overnight dexamethasone suppression test
Give dexamethasone 1 mg at approximately 11 pm and measure serum cortisol the following morning.
Plasma-free or urinary fractionated metanephrines
Particularly important when imaging is not clearly consistent with a benign lipid-rich adenoma or symptoms suggest phaeochromocytoma.
Aldosterone-to-renin ratio
Arrange in patients with hypertension or unexplained hypokalaemia. Check potassium and consider medication effects when interpreting the result.
Imaging information to obtain
- Maximum lesion diameter
- Unenhanced CT attenuation in Hounsfield units
- Homogeneous or heterogeneous appearance
- Comparison with any previous imaging
- Adrenal-protocol CT or MRI findings, if performed
Additional tests when clinically indicated
- Electrolytes and renal function
- HbA1c or fasting glucose
- DHEAS, androgens or steroid precursors if malignancy is suspected
- Relevant previous imaging and oncology history
Refer for endocrine surgical assessment.
Routine or early referral
- Any confirmed or suspected hormonally active lesion
- Lesion measuring 4 cm or greater
- Indeterminate or heterogeneous imaging appearance
- Interval growth on surveillance imaging
- Bilateral adrenal lesions requiring assessment
- Adrenal lesion in a younger patient
- Uncertainty regarding investigation or follow-up
Urgent discussion or referral
- Suspected phaeochromocytoma
- Imaging suspicious for adrenocortical carcinoma
- Rapidly enlarging lesion
- Local invasion or suspicious metastatic disease
- Severe or difficult-to-control hormone excess
- Acute deterioration potentially related to the adrenal lesion
Investigations do not need to be complete before referral where imaging is concerning or clinical suspicion is high.
Helpful information to include.
Refer a patient or discuss a case.
GPs and specialists are welcome to contact the rooms directly when advice regarding investigation or referral urgency is required.