Effects Of Selective Regional Lymph Node Irradiation And Innvolvement Field Irradiation On T Lymphocyte In Peripheral Blood Of Patients With Thoracic Esophageal Cancer

BackgroundEsophageal cancer is one of the major malignant tumors in China.The latest cancer data in China show that the incidence and mortality of esophageal cancer rank fourth among malignant tumors.The occurrence and development of esophageal cancer are closely related to the immune function of our body.Radiotherapy not only kills tumor cells,but also affects the immune function of the body.There are two methods to delineate the target area of radical radiotherapy for locally advanced esophageal cancer,namely selective nodal irradiation(ENI)and involved-field irradiation(IFI),which are still controversial.Currently,A large number of studies have shown that there is no significant difference in regional failure,local control rate and overall survival rate between cumulative field irradiation and selective lymphatic drainage area irradiation,but acute radiation injury has been significantly reduced.In this study,the changes of T lymphocyte subsets before and after treatment were monitored to further evaluate the effects of the two radiation modes on immune function,in order to provide more powerful evidence for the design and delineation of target areas for radiotherapy of esophageal cancer.ObjectiveTo investigate the changes of immune function in patients with esophageal squamous cell carcinoma before and after treatment with selective nodal irradiation(ENI)and involved-field irradiation(IFI),and to analyze the feasibility of involving-field irradiation combined with clinical data.Methods106 patients with thoracic esophageal squamous cell carcinoma confirmed by pathology from September 2016 to March 2019 were collected.All patients received intensive modulated radiation therapy(IMRT)and concurrent TP regimen chemotherapy.The prescription dose of PTV was 59.4 Gy,1.8 Gy/time,5 times/week.A case-control study was conducted.The patients were divided into ENI group and IFI group according to the range of radiation.The changes of T lymphocyte subsets in peripheral blood before and after treatment were monitored.Results1.There was no significant difference in CD3+,CD4+,CD8+ count and CD4+/CD8+ratio between ENI group and IFI group before treatment(P > 0.05).2.The absolute counts of CD3 + and CD4 + in ENI group and IFI group after radiotherapy were significantly lower than those before radiotherapy(P < 0.01),and the decrease level in ENI group was more significant than that in IFI group(P < 0.05).3.The absolute count of CD8 + in ENI group and IFI group did not decrease significantly after radiotherapy compared with that before radiotherapy(P > 0.05),and there was no significant difference in the absolute count of CD8 + between ENI group and IFI group(P > 0.05).4.The ratio of CD4 +/CD8 + in ENI group and IFI group decreased significantly after radiotherapy compared with that before radiotherapy(P < 0.01).And there was no signifycant difference in CD4 +/CD8 + ratio between ENI group and IFI group after radiotherapy(P > 0.05).ConclusionsPatients with esophageal cancer have obvious low cellular immune function.Both IFI irradiation therapy and ENI irradiation therapy can further decrease the immune function of the body to some extent.However,compared with ENI irradiation,IFI irradiation has less immunosuppression on the body,which is feasible in the selection of radiotherapy target area for late esophageal cancer.