Correlation and Prognostic Values of Glucose Metabolism-Related Markers on Dual-Phase FDG PET/CT in Non-Small-Cell Lung Cancer

Abstract

To evaluate the relationship and prognostic values of glucose metabolism-related markers with temporal changes of 18F-FDG uptakes on dual-phase PET/CT in non-small-cell lung cancer. We reviewed records of 151 patients with NSCLC who underwent pretreatment dual-phase 18F-FDG PET/CT scans acquired at 1 h and 2 h after injection. The SUV increment (SUVinc) of the primary lung tumor was the 2-h SUVmax minus the 1-h SUVmax. The retention index (RI) was calculated by dividing the increase in the 2-h SUVmax by the 1-h SUVmax. Immunohistochemical studies of glucose transporter 1 (GLUT-1) and hexokinase 2 (HK-2) on the paraffin-embedded pre-treatment tumor samples were performed. Correlations of metabolic markers with parameters extracted from dual-phase FDG-PET and patient survivals were analyzed. Expressions of GLUT-1 and HK-2 were positively correlated in lung tumors (P< 0.001). The SUVinc > 1 and RI > 15% had the best discriminative yield for disease-free survival (DFS). High-level expressions of both GLUT-1 and HK-2 were significantly correlated with SUVinc > 1 (all P< 0.01). However, neither GLUT-1 nor HK-2 expressions were significantly correlated with higher RI (P= 0.26 and 0.40, respectively). Both GLUT-1 and HK-2 were prognostic factors and associated with poor survival in NSCLC patients. Patients with co-overexpression of GLUT-1 and HK-2 had the worst DFS (P = 0.002). High-level expressions of both GLUT-1 and HK-2 are significantly correlated with the increment of SUV but not RI on dual-phase FGD PET. GLUT-1 and HK-2 are prognostic markers in NSCLC.