Non-small cell lung cancer: evaluation of pleural abnormalities on CT scans with 18F FDG PET.
OBJECTIVE
To evaluate the accuracy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in differentiation of pleural malignancy and cancer-unrelated pleural disease in patients with non-small cell lung cancer (NSCLC) and pleural abnormalities at computed tomography (CT).


METHODS
In 92 patients, pleural abnormalities were detected at contrast material-enhanced thoracic CT, which was performed for newly diagnosed NSCLC (n = 41) or restaging (n = 51). CT findings were negative for pleural malignancy when pleural effusion with attenuation of 10 HU or less and/or rib fractures with no evidence of pathologic fracture were present; findings were indeterminate when pleural effusion with attenuation greater than 10 HU and/or solid pleural abnormalities without osseous destruction of the chest wall were present; and findings were positive if any osseous destruction of the chest wall adjacent to a pleural mass was present. All patients underwent FDG PET. Findings were negative for pleural malignancy if pleural activity was absent, equal to, or less than mediastinal background activity; findings were positive if pleural activity was higher than mediastinal background activity. Reading of CT and FDG PET scans was first performed separately and then was combined. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPP), and accuracy were calculated for CT and FDG PET separately and for CT and FDG PET combined, with cytologic and/or histologic analysis as standard of reference.


RESULTS
In detection of pleural malignancies, CT findings were indeterminate in 65 (71%) patients and true-negative in 27 (29%). Respective sensitivity, specificity, PPV, NPV, and accuracy of FDG PET in detection of pleural malignancies were 100%, 71%, 63%, 100%, and 80%; and those of CT and FDG PET combined, 100%, 76%, 67%, 100%, and 84%.


CONCLUSIONS
Findings suggest that a negative FDG PET scan for indeterminate pleural abnormalities at CT indicates a benign character, while positive findings on an FDG PET scan are sensitive for malignancy.
Schaffler
Gottfried J
GJ
Department of Radiology, University Hospital Graz, Auenbruggerplatz 9, A-8036 Graz, Austria. gottfried.schaffler@kfunigraz.ac.at
Wolf
Gerald
G
Schoellnast
Helmut
H
Groell
Reinhard
R
Maier
Alfred
A
Smolle-Jüttner
Freya M
FM
Woltsche
Michael
M
Fasching
Gerlinde
G
Nicoletti
Rudolf
R
Aigner
Reingard M
RM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000150:complications* / Q000628:therapy; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000150:complications* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010995:Pleural Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D010997:Pleural Neoplasms / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18