Focal pulmonary abnormalities: evaluation with F-18 fluorodeoxyglucose PET scanning. 
The authors assessed the role of positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose (FDG) in differentiation of benign from 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 masses (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 had been radiographically stable for at least 8 years.  Quantitative analysis was performed by calculation of a standardized uptake ratio (SUR).  Thirty-three malignant lesions had a mean SUR (+/- 1 standard deviation) 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 FDG PET is accurate in differentiation of benign from malignant focal pulmonary abnormalities.