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.