ESR1 and breast cancer: Patients with TNBC (HR, 2.24; 95% CI, 1.75 to 2.87) and ER−, PR−, and HER2+ BC (HR, 1.50; 95% CI, 1.09 to 2.06) had higher risk of distant recurrence than those with ER+ or PR+ BC and HER2− BC.