ESR1 and neoplasm: Factors significantly correlated to favorable distant disease-free survival at 5-year follow-up (in this cohort of patients receiving adjuvant tamoxifen therapy) included positive ER and PgR status (P = 0.005 and P = 0.037, respectively) and negative CK5/14 and EGFR status (P = 0.035 and P = 0.005, respectively), but not HER2 and lymph node status, while tumor size and a high S-phase fraction reached marginal significance.