Differential diagnosis of lung tumor with positron emission tomography: a prospective study.
To predict the nature of non-calcifying lung tumors, we performed a prospective study of 46 cases with L-[methyl 11C]methionine (MET, 24 cases) and 18F-fluorodeoxyglucose (FDG, 22 cases) using positron emission tomography (PET). Mean tumor/muscle radioactivity ratios are 5.3 +/- 2.0 (n = 14) for malignant and 1.9 +/- 0.9 (n = 10) for benign with MET (p less than 0.001), and 4.4 +/- 2.2 (n = 12) and 1.5 +/- 0.3 (n = 10), respectively, with FDG (p less than 0.001). The ratios indicate that malignant tumors have higher metabolic demand than benign lesions. Tumors less than 1 cm in diameter were difficult to accurately evaluate due to PET resolution. Compared to the diagnosis at pathology, the MET study showed a sensitivity of 93% (13/14), a specificity of 60% (6/10), and an accuracy of 79% (19/24). The FDG study showed 83% (10/12), 90% (9/10), 86% (19/22), respectively. No significant differences were observed between the two tracers. This study suggests that PET studies using either MET or FDG may be very useful for the differential diagnosis of lung tumors.
Kubota
K
K
Department of Radiology and Nuclear Medicine, Tohoku University, Sendai, Japan.
Matsuzawa
T
T
Fujiwara
T
T
Ito
M
M
Hatazawa
J
J
Ishiwata
K
K
Iwata
R
R
Ido
T
T
D000328:Adult; D000368:Aged; D002250:Carbon Radioisotopes; D003847:Deoxyglucose / Q000031:analogs & derivatives; D003937:Diagnosis, Differential; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives; D008875:Middle Aged; D011446:Prospective Studies; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose; D008715:Methionine; C038344:methionine methyl ester