The Ability of FDG Uptake Ratio and Glut-1 Expression to Predict Mediastinal Lymph Node Metastasis in Resected Non-small Cell Lung Cancer

Abstract

Background: This study was designed to evaluate the FDG uptake ratio of mediastinal node and primary tumors using integrated PET/CT imaging combined with Glut-1 expression of the primary tumor in order to predict the N2 status more accurately in NSCLC patients. Material and Method: Patients who underwent integrated PET/CT scanning with a detectable mSUV for both primary tumors and mediastinal lymph nodes were eligible for this study. The FDG uptake ratio between the mediastinal node and the primary tumor was calculated. Result: The average mSUV of primary tumors and mediastinal nodes were, respectively, 7.4±2.2 and 4.2±2.2 in N2-positive patients and 7.6±3.7 and 2.8±6.9 in N2-negative patients. The mean FDG uptake ratio of mediastinal node to primary tumor were 0.58±0.23 for malignant N2 lymph nodes and 0.45±0.20 for benign lymph nodes (p＜0.05). Models which combined Glut-1 expression with an FDG ratio have better diagnostic power than models that use the FDG uptake ratio alone. Conclusion: In some patients with a previous history of pulmonary tuberculosis or other inflammatory lung diseases, an FDG uptake ratio combined with Glut-1 expression may be useful in diagnosing mediastinal node metastasis more exactly.