A Prospective Clinical Study Of Radical External Beam Radiotherapy And External Beam Irradiation Combined With Intracavity Brachytherapy As Treatment Of Esophageal Cancer

Esophageal cancer is a type of digestive tract tumor with poor prognosis,and is also one of the ten malignant tumors endangering human health.According to real-time data of WHO,half of the new cases and deaths of esophageal cancer in the world are in China,accounting for about 55%of the global total.Although the overall survival rate of esophageal cancer patients in China is slightly better than the global average,the 5-year survival rate is only 20%-30%.The reason is that 70%of the patients in China are already in the middle and late stage when they seek medical treatment,thus losing the chance of radical surgical resection.Multimodality therapy is an accepted strategy for the treatment of esophageal cancer,but despite advances in various treatment modalities,the treatment of esophageal cancer has been poor.The poor prognosis of patients is associated with the diagnosis of advanced and metastatic stage and the tendency to metastasize,even in small tumors.A historical series of external radiotherapy alone reports a 5-year survival rate of 0-10%.Low survival after initial radiotherapy may be due to local persistence or recurrence of the tumor,which occurs in up to 85%of cases.Higher doses of radiation to the tumor may improve local control,but may increase the risk of toxicity of OARs.Endoesophageal brachytherapy can deliver a high dose of radiation to the tumor itself while protecting the surrounding normal tissue.This study compared the therapeutic effect and side effects of concurrent chemoradiotherapy（CCRT）plus HDR intracavity brancytherapy（HDRBT）and concurrent chemoradiotherapy（CCRT）in the treatment of esophageal cancer,so as to provide a reasonable therapeutic plan for radical radiotherapy of esophageal cancer.Methods:Fifty?four patients of locally advanced carcinoma esophagus were allocated to CCRT and CCRT+HDRBT arms.Both groups were treated with definitive concurrent chemoradiation,Patients received paclitaxel at a dose of 45 mg/m² followed by carboplatin at a fixed area under the curve（AUC）of 2,as a weekly regimen with RT,and received 50 Gy of EBRT,2Gy per fraction over 5 weeks.After 2 weeks,the CCRT group was treated with EBRT boost of 10 Gy in 5 fractions,while the CCRT+HDRBT group received intraluminal high HDR brachytherapy boost of 10 Gy in 2 fractions.Results:The overall response rate was 91.89%in CCRT group and 100.0%in CCRT+HDRBT group.The results of rank sum test analysis showed that the difference between the two groups was not statistically significant（Z=-0.78,p=0.436）.The relief rate of dysphagia was 83.8%and 94.1%in CCRT and CCRT HDRBT groups.Statistical analysis using Chi-squared test with continuity correction showed that the difference was not significantc²=0.38 and p=0.539.The results of multivariate analysis by the Cox proportional hazards model shaw sd.that T stage was the independent prognostic factor of OS and PFS,tumor length was an independent prognostic factor of LRFS.differences were statistically significant（p<0.05）.The incidence of severe late toxicity in CCRT group was 13.5%,and 11.76%in CCRT+HDRBT group.The incidence of esophageal toxicity in the two groups was not statistically different（independent t test）.The incidence of late lung toxicity in the CCRT+HDRBT group was lower than that in the CCRT group（Z=-1.994,p=0.046）.The single-lung V₂₀ and double-lung V₂₀ in the CCRT+HDRBT group were smaller than those in the CCRT group,and the differences were significant by t test（p<0.05）.Conclusion:1.HDRBT combined with EBRT is effective in the treatment of esophageal cancer,which may provide a better treatment regimen.2.HDRBT combined with EBRT is a well tolerated and safe esophageal cancer treatment with mild side effects.3.In esophageal treatment,T stage and tumor length are independent factors affecting prognosis.