F-18-Fdg-Pet/Ct Evaluation Of Indeterminate Adrenal Masses In Noncancer Patients

Context: Adrenal tumors in noncancer patients are common.Objective: Evaluate performance of F-18-fluorodeoxyglucose positron emission tomography computed tomography (F-18-FDG-PET/CT) in distinguishing between benign and malignant adrenal tumors.Design: Retrospective chart review 2010-2019.Setting: Academic institution.Patients: One hundred and seventeen noncancer patients, defined as having no history of cancer or with cancer in remission for >= 5 years, completed F-18-FDG-PET/CT to evaluate adrenal masses, with pathologic diagnoses or imaging follow-up (>= 12 months).Intervention: F-18-FDG-PET/CT of 117 indeterminate adrenal masses.Main Outcome Measures: Receiver operator characteristic curve of the ratios of adrenal lesion standardized uptake value (SUV)max to liver SUVmean and of adrenal lesion SUVmax to aortic arch blood pool SUVmean were constructed.Results: Seventy benign and 47 malignant masses (35 adrenocortical carcinomas [ACCs], 12 adrenal metastases) were identified. Malignant masses had higher median liver SUV and blood pool SUV ratios than benign masses (6.2 and 7.4 vs 1.4 and 2.0, P <.001). Median liver and blood pool SUV ratios of ACC (6.1 and 7.3, respectively) and metastases (6.7 and 7.7, respectively) were higher than those of than adenomas (1.4 and 2.2, P <.05 for all comparisons). Optimal liver SUV ratio to discern between benign and malignant masses was 2.5, yielding 85% sensitivity, 90% specificity, and 7 false negative results (including 3 ACCs). Optimal blood pool SUV ratio was 3.4, yielding 83% sensitivity, 90% specificity, and 8 false negative results (including 4 ACCs).Conclusion: When used in conjunction with other clinical assessments, F-18-FDG-PET/CT can be a valuable tool in evaluating adrenal masses in noncancer patients.