Objective: This preliminary study was to evaluate the characteristics of indeterminate solitary pulmonary lesions in patients with renal cell carcinomas (RCC) using 18F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Material and Methods: Fifteen patients with RCC were found to have solitary pulmonary lesions with indeterminate chest X-ray and CT findings. Pulmonary metastases were suspected in all cases so whole body surveys with FDG-PET were performed. Results: FDG-PET correctly identified 9 true-positive and 4 true-negative cases. However, FDG-PET failed to interpret 1 false-positive and 1 false-negative case. Standard uptake values (SUV) were used as parameters to differentiate the solitary pulmonary lesions. Using SUV >2.5 as the cutoff to diagnose malignancy, the sensitivity, specificity, and accuracy of FDG-PET were 90, 80, and 87%, respectively. Conclusion: We conclude that FDG-PET is an accurate modality to differentiate solitary pulmonary lesions in patients with RCC.
