BACKGROUND¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) is considered as one of the most valuable diagnostic methods of chest malignant tumors, except for pathological diagnosis. But in clinic, the cases whose diagnosis of ¹⁸F-FDG PET is different from pathological diagnosis are not rare. This study is to evaluate the initial value of ¹⁸F-FDG PET in the diagnosis and staging of the chest malignant tumors.

METHODSFifty-one cases of chest tumors in Xi'an who underwent ¹⁸F-FDG PET were collected. Additionally, pathologic diagnosis had also been experienced on the patients through operation, percutaneous puncture, bronchoscopy or film preparation of pleural fluid. By the comparison of ¹⁸F-FDG PET diagnosis and the pathologic diagnosis, accuracy, sensitivity, specificity, false positive rate, positive predictive and negative predictive of ¹⁸F-FDG PET were calculated.

RESULTSIn 51 patients, there were 34 patients whose ¹⁸F-FDG PET diagnoses were consistent with the pathological diagnoses, including 31 true positive, 3 true negative. Out of another 17 patients, 11 were false positive, including 2 sarcoidosis, 6 tuberculosis of the lung, 2 inflammatory pseudotumor of the lung and 1 pulmonary cryptococcosis, and 6 were false negative. The calculated values were 66.67% on the overall accuracy, 83.78% on sensitivity, 21.43% on specificity, 78.57% on false positive rate, 16.21% on false negative rate, 73.81% on positive predictive value and 33.33% on negative predictive value.

CONCLUSIONSCurrently, ¹⁸F-FDG PET is still one of the most advanced unwounded technologies for the chest malignant tumor diagnosis. However, this technology experiences difficulties in detection of some high metabolized benign disease, such as tuberculosis from malignant tumor. Hence, in order to take advantage of ¹⁸F-FDG PET technology and have more accurate diagnosis of chest tumors, both results from the ¹⁸F-FDG PET and the clinic actuality should be considered.