Effect And Clinical Significance Of External Beam Radiotherapy On Different Lymphocyte Subsets In Patients With Cervical Cancer

Objective: To explore the effect of radical external beam radiotherapy on lymphocyte in patients with cervical cancer and the distribution characteristics of lymphocyte in cervical cancer patients of different ages and different periods before and after radiotherapy,analyze the influence of lymphocyte on local control after radiotherapy,and explore the influence of radiotherapy on immune system.Methods: A total of 120 patients with cervical cancer who received radical radiotherapy in the gynecological cancer Clinic of Shengjing Hospital Affiliated to China Medical University from January 2021 to July 2022 were selected.A total of 120 patients with cervical cancer who received radical radiotherapy in the gynecological oncology Clinic of Shengjing Hospital Affiliated to China Medical University from January 2021 to July2022 were selected.Thirteen indicators of the patients were obtained one week before and one week after external pelvic irradiation.It included the respective percentages of total T cells,CD8+T cells,CD4+T cells,NK cells,total B cells,NK-like T cells and regulatory T cells,as well as the respective absolute counts of total T cells,CD8+T cells,CD4+T cells,NK cells and total B cells and the ratio of CD4/CD8.In addition,imaging examination(MR,PET-CT)was performed to obtain the changes of cervical local lesions before and after pelvic external irradiation.Patients were grouped according to age,clinical stage and radiotherapy plan,and the differences between and within groups were compared and analyzed by statistical methods,and the correlation between different lymphocyte subsets,different clinical characteristics and local focal control effect was analyzed.Results: After radiotherapy,total T cells,CD8+T cells,NK cells,NK-like T cells and regulatory T cells increased,while CD4+T cells,CD4+/ CD8+ and total B cells decreased.From the cell count,T cells,NK cells and total B cells decreased significantly(P<0.05).Without treatment,there was no difference in the distribution of 13 indicators among patients of different ages and different periods.After external irradiation,total T cells and CD8+ T cells in advanced patients increased,while CD4+ T cells and CD4+/CD8+ decreased(P<0.05),while there was no difference in the four indexes before and after radiotherapy in early patients.NK cells were elevated after radiotherapy in early patients,but no difference was found in advanced patients(P<0.05).After external irradiation,NK cells increased and CD4+ T cells decreased in the young patients,but there was no difference in the old patients(P<0.05).Compared with patients without extension field,total T cells and CD8+T cells were significantly increased in patients with extension field(P<0.01),while CD4/CD8 and NK cells were decreased(P<0.05).CD8+T cells,CD4+T cells,NK cells,total B cells and regulatory T cells had no statistical significance on partial remission of local lesions(P<0.05).Conclusion: Through the direct killing effect of radiotherapy,the absolute count of different lymphocytes decreased,but from the analysis of proportion,radiotherapy enhanced the anti-tumor immune effect of lymphocytes and also enhanced the immune suppression of the body.Before radiotherapy,there was no difference in lymphocyte distribution among patients of different ages and different periods.For patients with stage I-II or cervical cancer less than 58 years old,radiotherapy was more dependent on NK cells and CD4+T cells.For stage III-IV patients,radiotherapy mainly affects CD4+T cells and CD8+T cells.CD4+T cells,CD8+T cells,NK cells,total B cells and regulatory T cells were not factors that promoted local control of PR.