Expression of E-cadherin and Ki67 in triple negative breast cancer and clinical significance

Objective To investigate the expression of E-cadherin and Ki67 in triple negative breast cancer (TNBC) and explore its clinical significance. Methods We retrospectively analyzed the clinical data from 77 female patients with TNBC in our hospital from January 2010 to December 2013. Immunohistochemistry was adopted to detect the expression of E-cadherin and Ki67. The relationship of protein expression with clinicopathological characteristics was analyzed using χ2 test. Five cases were lost in the follow-up, so we analyzed the survival and risk factors in 72 patients using Kaplan-Meier method, Log-rank test and Cox stepwise regression model. Results In all 77 cases, the expression of E-cadherin was correlated with the status of lymph nodes (χ2=16.428, P<0.001), and the expression of Ki67 was correlated with histological grade (χ2=7.218, P=0.007). The median follow-up time was 59 months. In the 72 patients with complete follow-up data, the disease-free survival and overall survival were 58.3% and 68.1%, respectively. The disease-free survival and overall survival in high E-cadherin expression group was significantly higher than those in low E-cadherin expression group (DFS rate: 75.9% vs 46.5%, χ2=7.553, P=0.006; OS rate: 82.8% vs 58.1%, χ2=5.132, P=0.023). The disease-free survival and overall survival in low Ki67 expression group was significantly higher than those in high Ki67 expression group (DFS rate: 84.0% vs 44.7%, χ2=9.486, P=0.002; OS rate: 92.0% vs 55.3%, χ2=9.006, P=0.003). According to the Cox stepwise regression analysis, lymphnode metastasis and advanced histological grade were independent risk factors of disease-free survival (OR=4.030, 95%CI: 1.854-8.757, P<0.001; OR=2.879, 95%CI: 1.359-6.100, P=0.006), and high expression of Ki67 and lymphnode metastasis were independent risk factors of overall survival (OR=5.067, 95%CI: 1.179-21.768, P=0.029; OR=6.253, 95%CI: 2.296-17.034, P<0.001). Conclusion The TNBC patients with the high E-cadherin expression and low Ki67 expression have good prognosis, which can provide guidance for the individualized treatment of breast cancer. Key words: Breast neoplasms; Ki-67 antigen; E-cadherin