Value Of ¹⁸FDG-PET In The Diagnosis Of Lung Cancer And Expression And Clinical Significance Of Glucose Transporter 1 In Lung Cancer

Objective:(l)To evaluated the ability of positron emission tomography(PET)with ～(18)fluoro-2-deoxyglucose(FDG) in identification of pulmonary mass andpreoperative mediastinal lymph node staging of lung cancer. (2)To analyze therelation between the expression of facilitative glucose transporter 1(GLUT1 )andthe value of standardized uptake value (SUV) in lung cancer.(3)TO examine theexpression of GLUT1mRNA in four non-small cell lung cancer(NSCLC) cell lines.(4) To investigate the prognosis significance of GLUT1 expression in cases ofNSCLC.Methods: Thirty four patients with pulmonary neoplasm were evaluated with～(18)FDG-PET and CT scan respectively. PET data were analyzedsemiquantitatively by calculating SUV and also by a visual method. PET and CTresults were compared with pathology results. The expression of GLUT1 wasstudied immunohistochemically in lung cancer(n=24), benign lung tumors andnormal lung tissues, and the intensity of GLUT1 in lung cancer was assessed bycomputer image analysis. Semiquantitative RT-PCR and cDNA sequence analysiswere employed to examine the expression of GLUT1mRNA in four NSCLC celllines. Our study also investigated the prognosis significance of GLUT1expression in 87 cases of NSCLC with pathologic stage I and Ⅱ.ResuIts:Using visual method, sensitivity and accuracy for detection of malignantmass of ～(18)FDG-PET were 93% and 85% respectively, whereas CT was 63% and53%(P <0.05) respectively The accuracy of preoperative mediastinal lymph nodestaging was l00% by PET and 78% by CT (P <0.05). Semiquanitative methodalso provide a accuracy of 74% for detection of malignant mass. All malignanttumors tested(n=24) were GLUTl positive, but no positive staining was seen inbenign tumors and normal tissues. Correlation between GLUTl expression andSUV was significant with r=0.86(P <0.05). GLUTlmRNA was expressed in fourcell lines, and the expression levels of two large cel1 lung cancer cell lines weresignificantly higher than the other two cell lines. In stage I and II, patients withhigh GLUTl expression had signicalltly lower survival time than those with lowGLUTl staining.ConcIusion: l8FDG-PET was more accurate than CT to discriminate the propertyof tumor, and stage mediastinal lymph node status of lung cancer. GLUT1 mayplay an important role in the glucose uPtake of lung cancer cells. The expressionof GLUTlmRNA was in concomitance with the malignancy of the cell lines.GLUTl is significant of poor prognosis indicator in cases of NSCLC.