The clinical value of 18F-FDG PET imaging for adrenal tumor

Objective: To assess the value of 18F-fluorodeoxyglucose (FDG) PET imaging in the diagnosis of adrenal tumor. Methods: 18F-FDG PET was performed on 21 patients with 22 adrenal tumors. The results were analysed with semiquantitative method and compared with the results come from other modalities, needle biopsy and surgical pathology. Results: Benign adrenal tumors were demonstrated in 9 patients by PET imaging without increased FDG uptake in the lesions; and malignant tumors were demonstrated in 12 patients with increased FDG uptake in the lesions. Compared with pathology results, the accuracy of PET was 100% and of CT (MRI) was 64%. In the benign lesions, tumor to normal tissue uptake ratios (TPN) were 0.3-1.3 with the mean of 0.7, standardized uptake values (SUVs) were 0.98-3.89 with the mean of 1.89. In malignant tumors, TPN were 3.1-15.1 with the mean of 6.9, SUVs were 3.10-15.52 with the mean of 6.41. Statistically significant difference was found between 2 groups (the t value of TPN and SUVs was 5.74 and 3.90, respectively, P<0.001) . Conclusions: FDG PET imaging possesses a super accuracy for the identification of adrenal tumor comparing with CT and MRI. It may take the place of needle biopsy in this regard