Objective:The aim of the study was to evaluate the efficacy of contrast material-enhanced computed tomography(CT) in assessing no-surgical treatment response in bronchogenic carcinoma.Methods:The 67 patients with bronchogenic carcinoma after no-surgical treatment underwent two-phase contrast material-enhanced computed tomography.Two spiral CT scans were obtained at 25 and 90 s respectively after nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector.Precontrast and postcontrast attenuation values on every scan were recorded and peak height was calculated.Enhancement pattern was evaluated on the image obtained at 25 and 90 s after injection of contrast medium.Results:Precontrast attenuation value,postcontrast attenuation values at 25 and 90 s were(41.26 ± 7.77) Hu,(56.45 ± 10.48) Hu,(70.82 ± 11.99) Hu,respectively.No statistically significant difference in precontrast attenuation was found between our results in this study and the results in our old study(mean precontrast attenuation 40.70 Hu) which was obtained in cases without any therapy(t = 0.593,P = 0.555﹥0.05).Peak height of bronchogenic carcinoma after no-surgical treatment [(29.40 ± 10.73) Hu] were significantly lower than that of bronchogenic carcinoma without any therapy obtained in our old study(mean peak height 35.79 Hu)(t =-4.874,P = 0.001 < 0.05).The 39 among 67 cases appeared homogeneous enhancement at 90 s.At 25 s,there were 26 cases with inhomogeneous enhancement,9 cases with homogeneous enhancement,2 cases with central enhancement,and 2 cases with peripheral enhancement among the 39 cases.Conclusion:Peak heights can reflect the blood supply of bronchogenic carcinoma and might be an index for evaluation of no-surgical treatment response in bronchogenic carcinoma.