Analysis of acute radiation injury in non-small cell lung cancer treated by three-dimensional conformal radiotherapy

Objective To analyze the influencing factors with radiation induced injury of nonsmall cell lung cancer(NSCLC)treated by three-dimensional conformal radiotherapy,in order to supply he reference criteria for optimize the treatment planning of NSCLC, further to improve the local control rate and quality of life of NSCLC patitents.Method From Aug 2000 to Dec 2004,107 NSCLC patients received three-dimensional conformal radiotherapy were enrolled in this study.In all the patients,48 patients accepted three dimensional conformal radiotherapy(3D-CRT),the other 59 patients accepted conventional radiotherapy(CRT)before later-course of 3D-CRT.All of the patients received the prescription dose between 60-78 Gy and the median dose 66 Gy.Results In the 107 patients,the rate of radiation induced injury was 62.6%.and the rate of≥2 grade was 38.3%.23 cases were classified in grade 2,14 cases in grade 3,4 cases in grade 4.Univariate analysis showed chronic obstructive pulmonary disease,number of beams field,lung mean dose,lung V5-V40 were important influencing factors on radiation induced injury.Further more,lung mean dose,lung V20 and chronic obstructive lung disease were likely to be the independent factors of radiation induced injury by Logistic model.Conclusions lung mean dose,chronic obstructive lung disease and lung V20 were the independent influencing factors on irradiated induced injury. Key words: Non-small cell lung cancer; Three dimensional conformal radiotherapy; Radiation induced injury; Dose-volume histogram(DVH)