Axillary lymph nodes pCR (apCR) versus breast pCR (bpCR): A meta-analysis involving 10,723 patients.

Abstract

e12630 Background: Pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) may improve the long-term survival of patients with breast cancer, as scored by disease-free survival (DFS) and overall survival (OS). Axillary lymph node pCR (apCR) is an important prognostic factor and may influence surgical de-escalation strategies; however, there is insufficient evidence to confirm that apCR produces a better prognosis than breast pCR (bpCR). The study aimed to perform a meta-analysis to assess the effect of apCR on survival compared with bpCR. Methods: We searched Cochrane Library, Web of Science, PubMed, Embase, and Clinical Trials.gov for breast cancer clinical trials with NAC. For included studies, we extracted the following data for analysis: study details, characteristics of participants, and survival data. Outcome data were reported as hazard ratios (HRs) and 95% confidence interval (CI) to measure the association between pCR and DFS, and OS. An I² test and subgroup analyses were performed to assess statistical heterogeneity in the included studies. Egger’s test and Begg’s funnel plot were used to determine potential publication bias. Results: We obtained data from 12 studies with 10,723 patients. Those patients with apCR had significantly better DFS than those with bpCR (HR=0.67, 95% CI, 0.60-0.76, P<0.00001), and no significant heterogeneity was observed between studies (I2=0%). As for OS, the HR significantly supported apCR (HR=0.72, 95% CI, 0.60-0.86, P=0.0002). There was no significant heterogeneity between studies (I2=35%). Subgroup analyses of each variable did not alter the results. Egger's test and Begg’s funnel plots indicated no significant publication bias in this analysis. Conclusions: This meta-analysis demonstrated that apCR is strongly associated with better DFS and OS than bpCR. This finding suggests that apCR has the potential to be an early surrogate endpoint for long-term prognosis.