ESR1 and breast cancer: However, Kaplan-Meier analysis results showed that CD4+ and CD8+ T cells as well as CD4/CD8 ratios in ER+ and HER2+ patients had very similar patterns for the predictions of clinical outcomes as those in the total breast cancer patients, suggesting that roles of both CD4+ and CD8+ T cells in breast cancer pathogenesis and progression are independent of ER and HER2 expression (Data not shown).