Dosimetric Factors Associated With Radiation-induced Lung Dagmage In Patients With Non-small Cell Lung Cancer Treated With Three-dimentional Conformal Radiotherapy

Objective To observe the incidence of radiation pneumonitis(RP) in patientswith NSCLC treated by3DCRT,and investigate the predictive value of dose volumeof the lung on RP.Materials and methods From June2010to December2010,68NSCLC patientstreated by3DCRT were retrospectively reviewed.35patients were male and the other33were female. All patients’age were from37~62,the middle age was55.And thepatients’ clinical stage were Ⅱb、Ⅲ、Ⅳ.Radiotherapy was delivered to a total dose of60–70Gy at2.0Gy per fraction.Results The incidence of radiation-induced lung damage was12％. In univariateanalysis，V5，Vl0，V15，V20，V25，V30and MLD were all significantly associatedwith radiation-induced damage.In Logistic regression analysis,V5was the only factorsignificantly associated with radiation-induced lung damage(χ2=5.15,P=0.034)．Conclusion.A number of dosimetric factors are significantly asaciated withradiation-induced lung damage.However,V5should be considered in radical3DCRTfor NSCLC patients to reduce the incidence of radiation-induced lung danlage.