Metabolic and anatomic characteristics of benign and malignant adrenal masses on positron emission tomography/computed tomography: a review of literature.

[adrenal incidentaloma]

PET /CT with (18 )F-fluorodeoxyglucose (FDG ) or using different radiocompounds has proven accuracy for detection of adrenal metastases in patients undergoing cancer staging . It can assist the diagnostic work-up in oncology patients by identifying distant metastases to the adrenal (s ) and defining oligometastatic disease that may benefit from targeted intervention . In patients with incidentally discovered adrenal nodules , so -called adrenal "incidentaloma " FDG PET /CT is emerging as a useful test to distinguish benign from malignant etiology . Current published evidence suggests a role for FDG PET /CT in assessing the malignant potential of an adrenal lesion that has been 'indeterminately ' categorized with unenhanced CT , adrenal protocol contrast-enhanced CT , or chemical-shift MRI . FDG PET /CT could be used to stratify patients with higher risk of malignancy for surgical intervention , while recommending surveillance for adrenal masses with low malignant potential . There are caveats for interpretation of the metabolic activity of an adrenal nodule on PET /CT that may lead to false-positive and false-negative interpretation . Adrenal lesions represent a wide spectrum of etiologies , and the typical appearances on PET /CT are still being described , therefore our goal was to summarize the current diagnostic strategies for evaluation of adrenal lesions and present metabolic and anatomic appearances of common and uncommon adrenal lesions . In spite of the emerging role of PET /CT to differentiate benign from malignant adrenal mass , especially in difficult cases , it should be emphasized that PET /CT is not needed for most patients and that many diagnostic problems can be resolved by CT and /or MR imaging .