Guideline: Management of Incidental Adrenal Lesions

Reference: Managing Incidental Findings on Abdominal CT: White Paper of the ACR Incidental Findings Committee. Berland, LL et al. JACR 2010; 7:754-733.

Macro name: Guideline adrenal

Macro last updated: 2/3/15

Adenoma < 4 cm

Incidental adrenal lesions measuring less than 4 cm with classic imaging features of adenoma require no dedicated imaging follow-up based on consensus guidelines. If there are clinical signs of adrenal hyperfunction, biochemical evaluation may be appropriate (JACR 2010; 7:753-773).

Myelolipoma

Incidental adrenal lesions with classic imaging features of myelolipoma require no dedicated imaging follow-up based on consensus guidelines (JACR 2010; 7:753-773).

1-4 cm, probably benign, no known CA

Assuming there is no prior imaging to document stability, incidental adrenal lesions measuring 1-4 cm without classic benign imaging characteristics are indeterminate, with the following recommendations based on consensus guidelines. If the patient has no known personal history of malignancy and the lesion demonstrates probably benign features (low density, smooth margins, homogeneous), a follow-up noncontrast CT could be obtained in 12 months to confirm stability. If the patient has a personal history of malignancy, PET-CT should be considered for further evaluation. If there are clinical signs of adrenal hyperfunction, biochemical evaluation may be appropriate. Biochemical testing to exclude pheochromocytoma could also be considered (JACR 2010; 7:753-773).

1-4 cm, suspicious, no known CA

Assuming there is no prior imaging to document stability, incidental adrenal lesions measuring 1-4 cm without classic benign imaging characteristics are indeterminate, with the following recommendations based on consensus guidelines. If the patient has no known personal history of malignancy and the lesion demonstrates suspicious features (heterogeneous, necrosis, irregular margins), adrenal mass protocol CT is recommended for further evaluation. If the patient has a personal history of malignancy, PET-CT should be considered. If there are clinical signs of adrenal hyperfunction, biochemical evaluation may be appropriate. Biochemical testing to exclude pheochromocytoma may also be considered (JACR 2010; 7:753-773).

1-4 cm, known CA

Assuming there is no prior imaging to document stability, incidental adrenal lesions measuring 1-4 cm without classic benign imaging characteristics are indeterminate. In a patient with a personal history of malignancy, PET-CT should be considered for further evaluation based on consensus guidelines (JACR 2010; 7:753-773).

> 4 cm, no known CA

In a patient with no known personal history of malignancy, incidental adrenal lesions measuring greater than 4 cm should be considered for resection, and surgical consultation is recommended based on consensus guidelines. If the patient has a known malignancy, PET-CT or biopsy could be considered. Biochemical testing to exclude pheochromocytoma may also be appropriate (JACR 2010; 7:753-773).

> 4 cm, known CA

In a patient a personal history of malignancy, incidental adrenal lesions measuring greater than 4 cm should be further evaluated with PET-CT or biopsy based on consensus guidelines. Biochemical testing to exclude pheochromocytoma may also be appropriate (JACR 2010; 7:753-773).

< 4 cm, stable for > 1 year

Based on consensus guidelines, adrenal lesions measuring less than 4 cm that have remained stable for 1 year or longer are considered benign, and require no further imaging evaluation. If there are clinical signs adrenal hyperfunction, biochemical evaluation may be appropriate (JACR 2010; 7:753-773).

Enlarging

Enlarging adrenal lesions are concerning for malignancy. In a patient with no personal history of cancer, biopsy or resection may be considered based on consensus guidelines. If the patient has a personal history of malignancy, PET-CT should be considered for further evaluation. Biochemical testing to exclude pheochromocytoma may be appropriate (JACR 2010; 7:753-773).

Washout no enhancement

Adrenal lesions that demonstrate no contrast enhancement are consistent with a benign etiology, typically either cyst or hemorrhage. No further imaging evaluation is required based on consensus guidelines (JACR 2010; 7:753-773).

Washout APW/RPW >= 60/40%

Adrenal lesions that demonstrate absolute percentage washout of greater than or equal to 60% or relative percentage washout of greater than or equal to 40% are consistent with adenoma, and require no further imaging evaluation. If there are clinical signs of adrenal hyperfunction, biochemical evaluation may be appropriate (JACR 2010; 7:753-773).

Washout APW/RPW < 60/40%

Adrenal lesions that demonstrate absolute washout percentage less than 60% or relative washout percentage less than 40% remain indeterminate. Based on consensus guidelines, adrenal protocol MRI could be considered for further evaluation, if not already performed. Alternatively, biopsy could be considered. Biochemical testing to exclude pheochromocytoma may also be appropriate (JACR 2010; 7:753-773).