EFNA1 and breast cancer: In our study, based on cluster analysis of mRNA expression levels of EPHA2, EFNB1, EFNB2, EPHB2, EPHB1, EPHA4, EPHB6, EPHA1, EFNA4, EFNA1, EFNA3, EPHA7, EFNB3, EPHA3, EPHB4, EPHB3 and EFNA5, we identified two patient clusters: the patients within cluster 2 were characterized by high EPH expression and were more prone to relapse with local metastasis, distant metastasis and had a shorter breast cancer-free survival time.