[Efficacy of neoadjuvant chemotherapy combined with bevacizumab versus neoadjuvant chemotherapy alone for Her2-negative breast cancer: a meta-analysis of randomized controlled clinical trials].

Objective: To evaluate the efficacy and safety of neoadjuvant chemotherapy combined with bevacizumab versus neoadjuvant chemotherapy alone for Her2-negative breast cancer.Methods: We searched PubMed, the Cochrane Library, Web of Science, CNKI, Wanfang Database and the abstracts of major international conferences in recent 5 years to identify prospective randomized controlled clinical trials that met the inclusion and exclusion criteria. Study selection and analyses were undertaken according to the Cochrane Handbook. Meta-analysis was performed using RevMan 5.3 software.Results: Six trials were identified with 4440 eligible patients. The results of this meta-analysis showed that the rate of pathological complete response (pCR) was higher in Her-2 negative breast cancer patients receiving bevacizumab combined with neoadjuvant chemotherapy than that in patients with neoadjuvant chemotherapy alone (24.7% vs 20.1%, RR=1.23, 95%CI:1.10-1.37, P<0.01). In addition, the pCR rate rose up when bevacizumab was added to neoadjuvant chemotherapy both in hormone receptor-positive patients (13.1% vs 10.2%,RR=1.28, 95%CI:1.04-1.58,P<0.05) and in hormone receptor-negative patients (46.3% vs 37.1%, RR=1.25, 95%CI:1.12-1.39, P<0.01). Statistical differences were observed in the rate of relevant adverse events such as hypertention (3.2% vs 0.6%, RR=5.292, 95%CI:2.933-9.549, P<0.01) and mucositis (10.5% vs 2.0%, RR=5.340, 95%CI:3.743-7.617, P<0.01) between the combination group and the chemotherapy alone group. Differences in other toxicities such as febrile neutropenia, infection, surgical complications, neutropenia and hand-foot syndrome were also found to be statistically significant between the combination group and the chemotherapy alone group (all P<0.05), while such difference was not found in the occurrence of peripheral neuropathy (P>0.05). Conclusion: The addition of bevacizumab to neoadjuvant chemotherapy in Her2-negative breast cancer can significantly improve pathological complete response, but may bring more grade 3 and 4 toxicities.More neoadjuvant trials need to be done to define subgroups of Her2-negative breast cancer that would have clinically significant long-term benefit from bevacizumab treatment.