23 studies evaluated the relationship between decreased E-cadherin expression and DFS, the results showed that E-cadherin low-expression predicted poorer disease-free survival (pooled HR 1.62, 95% CI 1.31–1.99, Figure 3) with significant heterogeneity (I2 = 70.9%, P < 0.001) of patients with breast cancer. The gene discussed is CDH1; the disease is breast cancer.