The Meta Analysis Of The Effect Of Radiotherapy On Local Recurrence After Breast-conserving Surgery For Breast Ductal Carcinoma In Situ

Objective: To analyze the effect of radiotherapy on local recurrence after breast conserving surgery in patients with intraductal carcinoma of the breast,and to discuss the safety of omitting radiotherapy.Methods: Search clinical studies in Pubmed,Medline,Embase,Cochrane Library,CNKI,Wanfang and other chinese and foreign database with "ductal carcinoma in situ","DCIS","breast conserving surgery","radiotherapy","Local Recurrence" as the main key words from January 2000 to October 2018.DCIS local recurrence was the main outcome index,and studies including radiotherapy factor as DCIS local recurrence risk factors were included to evaluate the quality of the literature and extract relevant data.Results: Through systematic search,a total of 831 articles were obtained,and 9retrospective cohort studies were finally included for meta-analysis.The sample size ranged from 80 to 3325,with a median follow-up time ranging from 5 years to 9.8 years.A total of 11268 patients with DCIS were included,including 1199 patients with local recurrence.The calculated local recurrence rate was 12%(Invasive recurrence 7% versus.In situ cancer recurrence 5%).Meta-analysis showed that the OR and 95% CI for factors of radiotherapy group and non-radiation group,palpable(0.44[0.27,0.73]),mammographic(0.46[0.37,0.57]),tumor size>10mm(0.36[0.16,0.81]),low-intermediate nucleus grade(0.46[0.33,0.63]),high nucleus grade(0.39[0.27,0.58]),necrosis(0.36[0.27,0.49]),family history(0.43[0.32,0.58]),with endocrine therapy(0.32[0.21,0.50]),age 40-60(0.48[0.37,0.63]),age>60(0.19[0.12,0.30]),number of excisions≧3(0.26[0.11,0.60]),margin width≦2mm(0.39[0.28,0.55]),margin width>2mm(0.51[0.41,0.63]),Z test showed there were statistically significant(P<0.05).While without necrosis(0.55[0.34,0.89]),age<40(0.71[0.35,1.44]),number of excisions≦2(0.27[0.04,1.62]),Z test showed there were no statistically differences(P=0.42、0.34、0,15).Conclusion: This study showed that the safety of omitting radiotherapy after breast conserving surgery of DCIS was positively related to age <40 years old,no necrotic components,and the number of margin excision≦2.