Objective:To compare the clinical efficiency of intensity modified radiotherapy(IMRT)/stereotactic body radiotherapy(SBRT)with that of IMRT in the treatment of local middle-late stage non-small cell lung cancer. Methods:Totally 90 patients with local middle-late stage non-small cell lung cancer(NSCLC)were randomly divided into two groups:experimental group(45 patients)and control group(45 patients). The experimental group was firstly treated by IMRT plan(conventional fractionation to a total dose of DT 50 Gy/5 weeks)and then followed by SBRT plan(hypo-fractionation to a total dose of DT 17.5 Gy/1 weeks).The control group was treated by mere IMRT plan(conventional fractionation to a total dose of DT 70 Gy/7 weeks). Lung enhanced CT scanning were performed 3 to 6 months after radiotherapy. Complete remission(CR) and partial remission(PR) rates were assessed according to the RECIST criterion. Acute inflammatory reaction of normal tissue were assessed according to the RTOG criterion. Results:The CR and PR rates of experimental group were remarkably higher than those of control group

84.44% and 66.67%

respectively. There were statistically significant differences between the two groups(P=0.05). The incidence rate of radioactive pneumonia in experimental group was inferior to that of control group

4.44% and 13.33%

respectively. The incidence rates of radioactive esophagitis were 44.44%and 48.89%

respectively. No significant difference was found between two groups regarding incidence rate of radioactive pneumonia(P=0.138)and radioactive esophagitis(P=0.822). No radioactive myelitis were found in either groups. Conclusions:Compared with IMRT

IMRT/SBRT is safer and more effective. And the acute tissue side reactions rarely occurred. Therefore

it could be extended and widely used in clinical work in the future.