ESR1 and neoplasm: Univariable analysis also identified large tumor size (HR = 2.05; 95% CI 1.18–3.55; p = 0.011), positive nodal status (HR = 3.80; 95% CI 1.74–2.44; p < 0.0001), negative ER status (HR = 2.13; 95% CI 1.26–3.62; p = 0.0051) and negative PgR status (HR = 2.34; 95% CI 1.36–4.01; p = 0.0021) as poor prognostic factors.