Prognostic Prediction Model Of Stage Ⅲ HER-2 Positive Breast Cancer Receiving Neoadjuvant Therapy Based On Seer Database

Objective:To study the factors influencing the prognosis of stage Ⅲ HER-2 positive breast cancer receiving neoadjuvant therapy and establish prognostic prediction model and risk grading system.Methods:The seer database was used to screen the patients with stage III HER-2 positive breast cancer who received neoadjuvant treatment from 2010 to 2019.Age(at the time of diagnosis),race,T stage,number of tumors,treatment time,lymph node metastasis rate,whether to receive radiotherapy,operation mode,ER,PR status,etc.are taken as biological indicators.Through single factor and multi factor analysis,meaningful indicators are screened out,and a nomogram is established to predict the prognosis of stage III HER-2 positive breast cancer receiving neoadjuvant treatment.The consistency index(C index),and receiver operating curve(ROC)and area under curve(AUC)were used for evaluation,and were validated by survival calibration curves.The patients were divided into three risk groups according to the calculation results of the nomogram,namely,low,medium,and high risk groups.The prognosis obtained by traditional AJCC tumor staging was compared,and the clinical efficacy of the nomogram was evaluated using decision curve analysis(DCA).Results:After univariate and multivariate Cox regression analysis,the independent factors affecting stage III HER-2 positive breast cancer included whether to receive radiotherapy,ER,PR status,histological grade,T stage,lymph node metastasis rate(P﹤0.01).A nomogram prediction model was constructed.The C index of the modeling group was0.732(95% CI 0.724-0.739),and the C index of the validation group was 0.728(95% CI0.721-0.737);The ROC curves for the 3,6,and 9 year survival rates in the modeling group showed that the area under the curve(AUC)was 0.724,0.719,and 0.775,respectively,compared to 0.773,0.699,and 0.758 in the validation group;The 3-year,6-year and 9-year survival correction curves show that the survival rates of the modeling and validation groups are highly correlated with the actual observed survival results.According to the comparison of the DCA between the risk stratification of nomogram and the traditional AJCC stages,nomogram can obtain higher net benefits and can accurately predict the survival rate of patients with different stratification levels.Conclusion:The prognostic nomogram of stage Ⅲ HER-2 positive breast cancer patients after neoadjuvant therapy has been successfully established and verified,which can be used for clinical reference.