A Study Of Individualized And Concurrent Radiotherapy For Nasopharyngeal Carcinoma Patients With Skull Base Bone Destruction

Objective:To explore whether there are differences in local control rate,disease-progression-free survival rate,overall survival rate and toxic reactions in nasopharyngeal cancer patients with damaged skull base bone during radiotherapy by evaluating the curative effect of radiotherapy through MR and individualized synchronous radiation therapy compared with nasopharyngeal cancer patients with conventional radiotherapy.Methods:Thirty-seven first-diagnosed nasopharyngeal carcinoma patients with skull base bone destruction and no distant metastasis were randomly selected from the Third Affiliated Hospital of Kunming Medical University from May 2017 to October 2018.The radiotherapy efficacy was evaluated at the 15th time of radiotherapy.According to the efficacy evaluation criteria of RECIST solid tumor,If PR is not achieved(tumor diameter reduction rate<30%in patients),the skull base is added synchronously,otherwise,the skull base is not added synchronously.At the same time,41 patients with locally advanced nasopharyngeal carcinoma diagnosed by histopathology,with complete imaging data and follow-up data,and with bone destruction of skull base after conventional radiotherapy were collected.The general clinical data of the patients were collected and statistically analyzed to compare the differences in local control rate,survival rate without distant metastasis,survival rate without disease progression,overall survival rate and toxic and side effects of nasopharyngeal carcinoma patients with two radiotherapy methods.Results:In the study group of 37 patients,3 patients were measured at the 15th time of radiotherapy with a tumor diameter reduction rate of 30%≥(i.e.,reaching PR),and did not receive skull base simultaneous volume addition.In 34 patients,the reduction rate was less than 30%(i.e.,PR was not reached),and skull base volume was added synchronously in all patients.All the 41 patients in the control group received conventional radiotherapy,and the patients in both groups were followed up for 30 months.1.The 1-year and 2-year local control rates of the study group were 100%and 97.2%,respectively;The control group were 90.2%and 82.9%,respectively.The local control rate of the study group was better than that of the control group in 1 and 2 years,and the difference between the two groups was statistically significant(2=5.267,P=0.022).The median recurrence time was 26 months in the study group and 15 months in the control group,and the difference between the two groups was statistically significant(P<0.05).2.In the study group,the 1-year and 2-year distant metastasis free survival rates were 86.1%and 83.3%,respectively;The control group were 85.4%and 78.0%,respectively.Compared with the control group,the 1-year and 2-year distant metastase-free survival rates were slightly higher in the study group,but the difference between the two groups was not statistically significant(2=0.584,P=0.445).The median time of distant metastasis was 10 months in the study group and 11.5 months in the control group,and there was no significant difference between the two groups(P>0.05).3.The 1-year and 2-year progression-free survival rates were 83.8%and 78.4%in the study group and 75.6%and 61.0%in the control group,respectively.The 1-and 2-year progression-free survival rates of the study group were superior to those of the control group,but the difference between the two groups was not statistically significant(2=2.219,P=0.088).The median time of disease progression was 10 months in the study group and 12 months in the control group,and the difference between the two groups was not statistically significant(P>0.05).4.In the study group,the 1-year and 2-year survival rates were 97.3%and 97.3%,respectively.One patient died 6 months after radiotherapy due to the failure of rescue for massive nasopharyngeal hemorrhage;The 1-year and 2-year survival rates in the control group were 100%and 100%,respectively.The overall survival rate of the control group was slightly higher than that of the study group,but the difference between the two groups was not statistically significant(χ2=1.108,P=0.292).5.Thirteen adverse events,including oral mucositis,dysphagia,dysphagia,radiodermatitis,hoarseness,hearing impairment,radioactive vomiting,visual impairment,weight loss,anemia,thrombocytopenia and radioencephalopathy,were statistically analyzed in the study group and the control group.There was no significant difference between 2 groups(P>0.05).Conclusion:The local control rate of patients with nasopharyngeal carcinoma can be improved by simultaneous radiotherapy in the field of skull base tumor.For locally advanced nasopharyngeal carcinoma patients with skull base bone destruction,by nuclear magnetic resonance imaging examination during radiotherapy after evaluating the effect of radiotherapy on the individual quantity of the synchronization of the skull base and radiation therapy,compared with the conventional radiotherapy of nasopharyngeal carcinoma patients,can improve the tumor local control,and did not increase the incidence of toxicity,effective save medical resources,avoid the waste of manpower and material resources.In terms of survival rate without distant metastasis,survival rate without disease progression,and overall survival rate,in-field concurrent dose radiotherapy for skull base tumors does not show obvious advantages over conventional radiotherapy,so a better treatment plan needs to be further studied.