Meta-analysis of radiotherapy on triple-negative breast cancer after breast conservation surgery

Objective: To systematically evaluate the influence of radiotherapy on triple-negative breast cancer (TNBC) patients treated with breast conservation surgery. Methods: Electronic databases including PubMed, Ovid, CBM, VIP and CNKI and seven journals in Chinese (including the Chin J Breast Cancer, Chin J Clin Oncol, Chin J Radiat Oncol, Chin J Cancer, Chin J Oncol, J Pract Oncol and Tumor) were searched. Clinical trials comparing survival rates of patients with TNBC and non TNBC treated with breast conservation surgery and radiotherapy were reviewed. The quality assessment and data extraction were performed by two reviewers independently. RevMan5.1 software developed by the Cochrane collaboration was used for Meta-analysis. The 5-year distant metastasis-free survival (DMFS), overall survival (OS) and local recurrence-free survival (LRFS) rates were the primary end points. Results: Five trials including 2345 patients with breast cancer were included in this systematic review. 417 patients had TNBC and 1928 patients had non TNBC. Meta-analysis showed that the 5-year DMFS and OS rates of patients with TNBC were lower compared with non TNBC (Z = 5.29, P = 0.000 and Z = 3.35, P = 0.001). There was no statistical significant difference in 5-year LRFS rate between patients with TNBC and non TNBC (Z = 1.35, P = 0.180). Conclusion: Radiotherapy provides good local control for patients with TNBC after breast conservation surgery. (authors)