Predictive value of circulating cell-free DNA in the survival of breast cancer patients: A systemic review and meta-analysis

PURPOSE: Circulating cell-free DNA (cfDNA) has been reported to predict outcomes in patients with various types of cancer. However, its prognostic value in patients with breast cancer is not well established still now. In this meta-analysis, we evaluated the prognostic role of cfDNA in breast cancer patients. METHODS: We performed systematic searches in electronic databases to identify studies that evaluated the prognostic value of cfDNA in breast cancer patients. The end points were progression-free survival (PFS) and overall survival (OS). The hazard ratios (HRs) and their 95% confidence intervals (95% CIs) were extracted to assess the prognostic significance of cfDNA. Subgroup analyses were also conducted. RESULTS: A total of 11 publications involving 1467 patients were included in this meta-analysis. cfDNA was shown to be significantly associated with PFS (HR 2.02, 95% CI 1.51–2.72, P < .001, I(2) = 82%) and OS (HR 1.75, 95% CI 1.01–3.05, P < .001, I(2) = 92%). The results of subgroup analyses also revealed that cfDNA was a good predictor of prognosis in breast cancer patients. CONCLUSION: Our meta-analysis indicated that cfDNA was associated with poor PFS and OS, thus it may help to predict outcomes of patients with breast cancer. However, further studies are needed to confirm our results.