Risk Prediction Of Radiation Pneumonia After Drug-Induced Lung Injury To The Lymphoma

Objective: To explore the clinical and dosimetric factors of the radiation pneumonia after drug-induced lung injury in mediastinal lymphoma,and to determin the threshold of dosimetric parameters related to incidence of radiation pneumonia.Methods: A retrospective analysis of 1028 patients with radiotherapy from December 2010 to December 2019 in Hnnan Cancer Hospital,and31 cases of drug-induced lung injury were finally included in the group.Fisher precise test,univariate analysis and nonparametric tests were used to analyze the predictors of radiation pneumonia after drug-induced lung injury,which include clinical factors such as sex,age,pathological type of lymphoma,disease stage,smoking history,mediastinal mass,bleomycin pulmonary toxicity,rituximab pulmonary toxicity,pulmonary function before radiotherapy,autologous hematopoietic stem cell transplantation and dosimetric factors such as V5、V10、V15、V20、V25 and MLD.Results: The incidence of radiation pneumonia was 77.42%(24/31),and no grade 5 radiation pneumonia occurred.The clinical factors including sex(p=0.08),age(p=1.00),pathological type of lymphoma(p=0.41),disease stage(p=0.55),history of smoking(p=0.15),mediastinal mass(p=0.08),pulmonary toxicity of bleomycin(p=0.413),pulmonary toxicity of rituximab(p=0.39),lung function before radiotherapy(p=0.07)and autologous hematopoietic stem cell transplantation(p=0.55)could not predict radiation pneumonia.Dosimetric factors including V5(p=0.001)、V10(p=0.001)、V15(p=0.004)、V20(p=0.003)、V25(p=0.002)and MLD(p=0.001)could significantly predict radiation pneumonia,and the threshold values are V5>47.36%(p<0.001)、V10>40.19%(p=0.001)、V15>22.22%(p=0.045)、V20>22.85%(p=0.007)、V25>15.53%(p=0.001)和 MLD>10.20Gy(p=0.001).V5(p=0.004)、V10(p=0.004)、V15(p=0.018)and MLD(p=0.027)could significantly predict grade 2radiation pneumonia(imaging standard).Conclusions:For patients with mediastinal lymphoma treated with chemotherapy combined with consolidation radiotherapy,the incidence of radiation pneumonia increased significantly after drug-induced lung injury.The common clinical factors were not significant in predicting the incedence of radiation pneumonia.Radiotherapy dosimetric parameters including V5,V10,V15,V20,V25 and MLD can predict the incedence of radiation pneumonia.The threshold values of these parameters are47.36Gy、40.19Gy、22.22Gy、22.85Gy、15.53Gy、10.20 Gy.V5,V10,V15 and MLD were significantly correlated with grade 2 radiation pneumonia(imaging standard).