FOCAL PULMONARY ABNORMALITIES - EVALUATION WITH F-18 FLUORODEOXYGLUCOSE PET SCANNING

The authors assessed the role of positron emission tomography (PET) wi th fluorine-18 fluorodeoxyglucose (FDG) in differentiation of benign f rom malignant focal pulmonary abnormalities seen on chest radiographs. Fifty-one patients underwent FDG PET scanning. Focal abnormalities at radiography included solitary pulmonary nodules (n = 38), pulmonary m asses (n = 5), and poorly marginated infiltrates or opacities (n = 8). Proof of diagnosis was obtained by means of transbronchial biopsy (n = 21), open lung biopsy (n = 14), percutaneous needle biopsy (n = 14), or cytologic evaluation of sputum (n = 1). A nodule in one patient ha d been radiographically stable for at least 8 years. Quantitative anal ysis was performed by calculation of a standardized uptake ratio (SUR) . Thirty-three malignant lesions had a mean SUR (+/- 1 standard deviat ion) of 6.5 +/- 2.9. Eighteen benign lesions had a mean SUR of 1.7 +/- 1.2. For a benign lesion with SUR of 2.5 or less, specificity of FDG PET was 100%, while sensitivity was 89%. These results suggest that FD G PET is accurate in differentiation of benign from malignant focal pu lmonary abnormalities.