ESR1 and breast cancer: Additionally, analysis of Kaplan–Meier plotter database (Gyorffy et al, 2010) indicated that lower SALL2 expression significantly correlated with poorer relapse‐free survival (RFS), distant metastasis‐free survival (DMFS), and overall survival (OS) in all breast cancer cases and in cases of ER+ breast cancer with tamoxifen therapy, but not in ER− breast cancer cases (Fig 1F; Appendix Fig S1A and B).