Objective Toexplore the feasibility of noninvasive late arterial phase enhanced CT images be used as a tool for evaluating tumor angiogenesis, ischemic necrosis and glucose metabolism, and providing important information for the comprehensive treatment plan in non small cell lung cancer (NSCLC). Methods 1. This quantitative study involved 52 patients with NCSLC. All the patients underwent an chest scan by a 64-slice CT(Sensation,Siemens,Germany) or a 256- slice CT(Brilliance iCT,Philips,Holland), before and 35 seconds after the administration of contrast agent iodixanol by a power injector (Ulrich Medical, Germany) at a rate of 3.0 mL/s through an 18-gauge intravenous catheter placed in an antecubital vein. The dose of the contrast medium delivered was 2 mL/kg of the patients body weight. The ischemic necrosis CT quantitative value (INCTQ) for NSCLC was measured on the late arterial phase enhanced CT images one day to six days before surgery. The images were acquired in 0.625 mm or 0.5 mm of scan thickness and in 3 mm of reconstruction thickness. The enhanced images were reconstructed in axial, sagittal and coronal directions. For the measurement of CT enhancement value (CT enhancement, CTe), a region of interest (ROI) was set at the center level of the tumor. The CTe was calculated by subtracting the plain CT value from the enhanced CT value. INCTQ including ischemic necrosis area and density information(CT value) was used to evaluate the necrosis degree of tumor. 2. Post-operative tissue specimen were routinely fixed in 10% formaldehyde and embedded. Each specimen was sliced in 3 μm and stained with “hematoxylin & eosin method” (H & E staining method). The immunohistochemistry was performed for CD34, Vascular endothelial growth factor(VEGF), Vascular endothelial growth factor Receptor 2(VEGFR-2), Hypoxia inducible factor (HIF-1α ), Carbonic anhydrase(CA IX), Glucose transporters (Glut 1 and Glut 3). EnVision two-step methods used for immunohistochemistry, the standard method was used to count tumor microvessel density (MVD), and those markers expression grade were recorded. Results 1. In 52 cases of NSCLC, the mean CTe value of the tumor was 26.47 ± 11.64 HU (ranged from 1 HU to 53.5 HU) , the mean INCTQ value was 0.95 ± 1.03 HU (ranged from 0 ~ 4.28HU). The CTe was negatively correlated with INCTQ, the correlation coefficient r = -0.122, P= 0.391. the lower CTe value was associated with the higher INCTQ value, the correlation coefficient r = -0.122, P= 0.391. 2. In 52 cases of NSCLC, the mean MVD value was 27.54 ± 15.74 (ranged from 4 to 66), the positive expression rate of VEGF, VEGFR – 2, HIF-1α, CA IX, Glut-1, Glut 3 were 71.2%, 73.1%, 73.1%, 48.1%, 71.2%, 69.2% respectively. The expression of Glut 1 was strongly correlated with the expression of Glut 3(P=0.000), while the expressions of HIF-1α, Glut-1, Glut-3, CA IX were not significantly correlated with the expression of VEGF, VEGFR – 2, however, the MVD mean values of different VEGF or Glut 1 expression grades were significant differences(P= 0.02, 0.015), and the MVD mean values of VEGF and VEGFR-2 coexpression, single expression and noexpression groups were significantly different, P = 0.024. 3. The CTe values were positively correlated with MVD value(r = 0.148, P= 0.294), The mean CTe values between the different expression grades of VEGF or VEGFR-2 or other tumor hypoxia markers were no obvious differences, but the mean CTe values of coexpression, single expression and no expression groups of HIF-1 alpha and CA IX were significant differences, P = 0.031. 4. The INCTQ value was negatively correlated with MVD value(r = 0.062, P= 0.661). The mean INCTQ values of different expression grades of VEGF or VEGFR – 2 were no obvious difference, but the mean INCTQ values of different expression grades of Glut 1 or Glut 3 were significantly difference , P = 0.000, and the INCTQ mean values of groups of HIF-1α and Glut 1 or Glut 3 or CA IX co-expression, single expression and no expression were significant differences, P = 0.024, 0.033 and 0.047. The INCTQ mean values of co-expression, single expression and no expression groups of Glut 1 and Glut 3, Glut 1 and CA IX, or Glut 3 and CA IX were significant differences, p=0.005, 0.017 and 0.010. Conclusions The late arterial phase CT enhancement value (CTe) of NSCLC can reflect the MVD of tumor tissue, which indicate the level of tumor angiogenesis; The INCTQ measured at Late arterial phase enhanced CT images of NSCLC can not only accurately reflect the degree of tumor tissue ischemia necrosis ,but also can accurately reflect the level of tumor tissue glucose metabolism. Therefore, late arterial phase CT examination of NSCLC can provide information about tumor angiogenesis, degree of ischemia necrosis as well as glucose metabolism for the comprehensive treatment plan of NSCLC.