UICC World Cancer Congress 2006

Methods: 128 patients of known malignancies and adrenal mass were included in this study. A total of 153 adrenal lesions (128 unilateral and 25 bilateral) were evaluated. All patients underwent FDG-PET for primary staging or evaluation of metastatic disease. PET was interpreted as positive if the FDG uptake was equal to or greater than that of the liver. PET was interpreted negative if the FDG uptake in the adrenal mass was less than liver. All the results were correlated with the clinical follow-up and/or biopsy results whenever available.

Results:FDG-PET findings were positive in 87 adrenal lesions. Eighty-one of these were eventually considered to be metastatic adrenal disease. In the remaining 6 lesions, 2 were adenoma, 1 was renal cell cancer, and 1 was pheochromocytoma while 2 did not showed any changes in lesion size on follow-up examinations. PET findings were negative in 66 adrenal masses, of which 55 eventually proved to be benign. The sensitivity, specificity, and accuracy of FDG-PET for detecting metastatic disease were 88%, 90%, and 89%, respectively.

Conclusion:FDG-PET is an accurate, noninvasive technique for differentiating benign from metastatic adrenal lesions detected on CT or MRI in patients with known malignancies. In addition, PET has the advantage of assessing the primary cancer sites and detecting other metastases.