The Impact Of Axillary Lymph Nodes Surgery Extent On The Prognosis Of Stage â…£ Breast Cancer: A SEER-Population Based Study

Objective: This study aimed to compare the impacts of sentinel lymph node biopsy(SLNB)and axillary lymph node dissection(ALND)on overall survival(OS)and breast cancer-specific survival(BCSS)in stage â…£ breast cancer.Methods: Patients diagnosed with stage â…£ breast cancer from 2004 to 2015 who underwent primary tumor resection were extracted from the Surveillance,Epidemiology,and End Results database.Kaplan-Meier analysis was used to estimate cumulative OS and BCSS.Cox regression model was used to study the risk factors.We also performed subgroup analyses of confounding factors.Results: A total of 11933 patients were studied.Compared with only breast surgery cohort,SLNB and ALND cohorts had a consistent improvement in OS and BCSS.Cox regression model showed that SLNB and ALND were independent risk factors for stage â…£ breast cancer.The risk of SLNB was higher than that of ALND(OS: HR = 1.11,95%CI: 1.035-1.191,p = 0.004;BCSS: HR=1.113,95%CI: 1.031-1.201,p =0.006).The distribution of confounding factors was not balanced among the three cohorts.Subgroup analyses showed that the prognosis of the ALND cohort was better than that of SLNB,especially in patients with a higher tumor burden(T4,N1-3),HER-2(+)breast cancer,and lung metastasis.Conclusion: SLNB and ALND have similar improvement in the prognosis of stage â…£ breast cancer due to selection bias.