Clinical Application Of Positron Emission Tomography (PET) With ～(18)F-fluorodeoxyglucose In Diagnosis, Therapy And Prognosis Of Patients With Lung Cancer

Lung cancer is one of the common malignant diseases in China. As a functional imaging modality, positron emission tomography (PET) with [18F] fluorodeoxyglucose (18F-FDG) supplies information about the glucose metabolism of tissues. Since malignant tumour cells show elevated FDG uptake, primary tumour and their metastases can be visualized in a whole-body examination. 18F-FDG PET imaging provides usefulness for initial diagnosis and staging. The aim of this study was to evaluate the value of 18F-FDG PET imaging in NSCLC staging, investigate the efficiency and influence factors of standardized uptake value (SUV) in diagnosing lung occupying lesions, research the role of 18F-FDG PET imaging in diagnosing and treating the patients with lung cancer , discuss the presumable problems of 18F-FDG PET imaging and their solution.ObjectiveTo investigate the diagnostic value of the SUV in 18F-FDG PET imaging and analyze the influence factors of SUV. For the patients whose illnesses have been diagnosed as lung cancer, to investigate the role of 18F-FDG PET imaging in diagnosis, treatment and prognosis.MethodsThis study could be divided into two parts. In the first one, we used 18F-FDG PET imaging to characterize lung occupying lesions. 18F-FDG PET was performed in 48 patients with lung occupying lesions and 10 healthy people. The SUV of each lesion was measured .Correlated with pathology, the sensitivity and specificity in diagnosis of pulmonary was calculated. The possibly influence factors of SUV wasanalyzed.In the second one, the treatment records of 92 patients with lung cancer were reviewed. Whole-body PET and CT were performed after therapy. All patients were followed up for 6 moths to 4 years. Evaluate the efficiency of PET and CT. Compare the SUV of patients who were alive and had no metastasis with that of the others, and study the relationship of SUV with patients' living condition.Resultshi diagnosing the lung occupying lesions, SUV of lung cancer group, lung benign disease group and comparison group were different one another. 18F-FDG PET imaging had a sensitivity of 93.62% and a specificity of 77.08%. The negative predictive value and the positive predictive value of the imaging was 82.35% and 83.02%, respectively. The difference between adenocarcinoma and squamous cell carcinoma was not notable. If we raised the threshold of SUV, we could find that the sensitivity increased, but the specificity decreased gradually.In the study of patients with lung cancer after therapy, the sensitivity, accuracy and negative predictive value of PET were higher than those of CT. The sensitivity of 18F-FDG PET imaging was 94.44%, and the specificity was 70.00%. The SUV of patients alive and with no metastasis was lower than the SUV of the others. Significant relationship between SUV and living condition was found in these patients.ConclusionCombining with clinical information, SUV is a good index to characterize lung occupying lesions and stage lung cancer. 18F-FDG PET imaging is a useful method for monitoring tumour response to therapy and for detecting recurrence. It can guide clinical doctors to make right therapy plans for patients.