A Comparative Analysis Of Adjuvant Chemotherapy Regimen AC-T And TAC In Early Breast Cancer

Objective:Retrospective analysis was performed on 739 patients with early breast cancer who were treated with AC-T and TAC adjuvant chemotherapy regimens in the Cancer Center of the First Hospital of Bethune,Jilin University.The efficacy and safety of the two regimens were compared,intending to stimulate the clinical practice.Clinical trials on efficacy comparison of the two programs were summarized and meta-analysis was conducted.Method:1.Retrospective analysis: We collected the list of patients with early breast cancer who received AC-T and TAC adjuvant chemotherapy in our center from December 2009 to December 2019,collected the basic data,clinicopathologic data,other treatment conditions and adverse reactions of the two groups,analyzed the factors influencing the prognosis of the patients in the real world,and compared the prognosis and adverse reactions of the two groups.2.Meta-analysis: According to the inclusion and exclusion criteria,the literatures about the efficacy comparison of two adjuvant chemotherapy regimens were screened for meta-analysis.The quality of the included literature was evaluated,relevant data were extracted,and data processing including heterogeneity test,sensitivity analysis,and subgroup analysis were performed.Result:1.Retrospective analysis1.1.There were 739 eligible patients,including 370 in the AC-T group and 369 in the TAC group.The data of two groups are roughly balanced and generally comparable.1.2.Univariate and multivariate comprehensive analysis showed that primary tumor size,Ki67,risk grade,adjuvant chemotherapy regimen and adjuvant endocrine therapy were Vindependent predictors of DFS,while recurrence was the only independent predictor of OS.1.3.TAC significantly improved DFS compared with AC-T regimen(P=0.031);There was no significant difference in OS between the two groups(P=0.629).The 3-year DFS rate of AC-T versus TAC was 84.0% vs 86.5%.The 5-year DFS rate was 74.9% vs 80.4%;The5-year OS rate was 94.3% vs 93.5%.1.4.Stratified analysis showed that in terms of DFS,TAC was significantly better than AC-T(P<0.05)for patients aged 35-60 years,stage Ⅰ and Ⅱ,hormone receptor negative,and moderate risk of recurrence;There was no significant difference in DFS between the two groups for patients < 35 years old and > 60 years old,with stratified lymph nodes,stage Ⅲ,stratified histological grades,positive hormone receptors,and high risk of recurrence(P>0.05).OS: In the above stratified analysis,there was no significant difference in OS between the two groups(P>0.05).1.5.In patients with lymph node negative,hormone receptor positive,HER-2 negative and histological grade 3,there was no significant difference in DFS(P=0.531)and OS(P=0.783)between the three adjuvant chemotherapy regimens: combination chemotherapy with anthracycline and paclitaxel,mainly chemotherapy with paclitaxel and mainly chemotherapy with anthracycline.1.6.Pathological staging and risk grade were independent predictors of Ki67 < 14%.1.7.The proportion of treatment regimens adjustment in TAC group was higher than that in AC-T group.The incidence of grade 3-4 hematological toxicity,leukopenia and neutropenia in TAC group was significantly higher than that in AC-T group(P<0.05).2.The meta analysis2.1.A total of 4 studies were included for meta-analysis,all of which were RCTs.A total of 6,986 people were included in the study,including 3,492 in the AC-T group and3,494 in the TAC group.Total effect size HR=0.90,95%CI: 0.77-1.05,P=0.19.There was no significant difference in DFS between AC-T regimen and TAC regimen.2.2.The published age subgroup analysis showed that HR = 0.99,95% CI: 0.87-1.11,P= 0.81 within 5 years,there was no difference in DFS between the two schemes in the subgroup;5 years ago,HR=0.81,95% CI: 0.67-0.99,P = 0.03.There were differences in DFS between the two schemes in the subgroup.AC-T decreased the risk of 19% DFS events compared with TAC.2.3.Sample size >1000,Caucasian population,follow-up > 5 years,positive lymph node: HR=0.90,95%CI: 0.77-1.06,P=0.22,no difference was found in DFS between the two subgroups.Sample size <1000,Asian ethnicity,follow-up <5 years,regardless of lymph node status: HR=0.82,95%CI: 0.32 to 2.12,P=0.68,no difference in DFS was found between the two protocols in this subgroup.Conclusion:1.Retrospective analysis showed that TAC was superior to AC-T in DFS in early HER-2 negative breast cancer.2.TAC adjuvant chemotherapy is a better choice for patients with early triple negative breast cancer.3.It is not recommended to choose high-intensity combination of anthracycline and paclitaxel for patients with high histological grade but few other risk factors.4.In general,the hematological toxicity of TAC regimen was more obvious than that of ac-t regimen.5.Meta analysis of RCTs: There was no significant difference in DFS between AC-T and TAC,and the results were not affected by the sample size,race,follow-up time and lymph node status.