Clinical Observation And Prognosis Of Ct-guided Three-dimensional Brachytherapy For ⅡB-ⅣA Cervical Cancer

Objective:To compare the clinical efficacy and adverse reactions between CT-guided three-dimensional brachytherapy and traditional two-dimensional brachytherapy in the treatment of stage II B-IVA cervical cancer.Methods:A retrospective study was conducted on 116 patients with stage IIB-IVA cervical cancer treated in zunyi medical university affiliated tumor hospital from January 2015 to January 2016.Fifty-six patients received CT-guided three-dimensional brachytherapy（3D group）and 60 patients received two-dimensional brachytherapy（2D group）.Intensity modulated radiation therapy（IMRT）was used in both groups.Paclitaxel 60mg/time or cisplatin 30mg/m²was used in the same period of chemotherapy once a week for 5-7cycles.Follow-up methods were outpatient and telephone follow-up.The clinical target volume dose(CTV_D90),target conformity index（CI）,minimum dose(D_2cm3),minimum dose(D_1cm3),objective remission rate（ORR）,disease control rate（DCR）,1,2,3 year overall survival rate（OS）,disease-free survival rate（DFS）and incidence of adverse reactions were compared between the two groups.Results:The median follow-up time was 36 months.CTV_D90in the 3D group was higher than that in the 2D group.The difference was statistically significant（P=0.028）.The CI value of 3D group was higher than that of 2D group,and the difference was statistically significant（P=0.013）.D2_cm3m3 of bladder and rectum in 2D group was higher than that in 3D group（P=0.046,0.041）.The values of ORR,DCR,OS and DFS in 3D group were higher than those in 2D group,but there was no significant difference between the two groups（P>0.05）.The incidence of acute radiation proctitis and radiation cystitis in 3D group was lower than that in2D group.The incidence of acute radiation proctitis（P=0.041）,1-2-year radiation proctitis（P=0.043,0.027）and 1-year radiation cystitis（P=0.045）were significantly different（P<0.05）.In univariate analysis,age,pathological type,FIGO stage,KPS score,adjuvant chemotherapy,CI value and CTV_D9090 were the factors affecting the 3-year survival rate of cervical cancer,and the difference was statistically significant（P<0.05）.In multivariate analysis,the independent risk factors affecting OS of cervical cancer were pathological type,FIGO stage,CTV_D9090 and CI value.Conclusion:Compared with traditional two-dimensional brachytherapy,CT-guided three-dimensional brachytherapy increased ORR,DCR and OS,DFS values for 3 years,but there was no significant difference between the two groups.CT-guided three-dimensional brachytherapy can reduce the incidence of adverse reactions and improve the accuracy of radiotherapy.Age,KPS score,pathological type,adjuvant chemotherapy,FIGO stage,CTV_D90and CI value are related to the prognosis of cervical cancer.FIGO stage,pathological type,CI value and CTV_D9090 are independent risk factors affecting prognosis.