Exploring The Differences In EBV-DNA Truncation Values And Survival Prognosis Among Nasopharyngeal Carcinoma Patients Before,during,and After Treatment

Background and Objective:The main criteria for predicting prognosis and guiding treatment of nasopharyngeal carcinoma patients are determined by the TNM staging system developed by the International Cancer Society/United States Joint Commission on Cancer(UICC/AJCC).However,patients with the same TNM stage may have different outcomes after adopting the same treatment mode.Therefore,we want to explore affordable and easily available EBV DNA indicators to compensate for the shortcomings of TNM staging systems.By collecting clinical data of nasopharyngeal carcinoma patients in our hospital,we divided them into low-risk and high-risk groups before,during,and after treatment,and explored the differences in survival prognosis between each group,in order to preliminarily grade the EBV-DNA load.Methods:In this study,206 patients with nasopharyngeal carcinoma who were treated in the our hospital from January 2016 to March 2023 were retrospectively analyzed.ROC curve was used to determine the truncated values of EBV DNA before,during and after treatment,and NPC patients were divided into 6 subgroups according to the truncated values.Taking PFS as the main research end point,Kaplan-Meier method was used to calculate PFS among six subgroups,and log-rank method was used to compare their survival curves.Results:The median follow-up time was 36 months(8-60 months).A total of 206 newly diagnosed NPC patients were collected,including 3 patients with stage I(1.5%),15 patients with stage II(7.3%),111 patients with stage III(53.9%),59 patients with IVA(28.6%)and 18 patients with stage IVB(8.7%).The median PFS of low-risk group and high-risk group before treatment(51 months vs36 months,P < 0.05),the median PFS of low-risk group and high-risk group after treatment(51 months vs36 months,P < 0.05),the median PFS of low-risk group did not reach after treatment,and the median PFS of high-risk group was 18 months.Conclusions:1.Whether before,during,or after treatment,the low-risk group had better Survival prognosis compared to the high-risk group.2.After treatment,the EBV-DNA copy number group was more different in PFS,and the EBV-DNA high-risk group was more risky after treatment.3.There was no significant correlation between gender,age,smoking history,T stage,and prognosis of NPC patients,while N stage was positively correlated with prognosis.