Abstract GS1-05: Trial Assigning Individualized Options for Treatment (TAILORx): An Update Including 12-Year Event Rates

Abstract Background: Late recurrence of breast cancer after 5 years accounts for about 50% of recurrences in hormone receptor (HR)-positive early breast cancer (EBC). TAILORx established non-inferiority of adjuvant endocrine therapy (ET) given for at least 5 years to chemotherapy plus ET (CET) in EBC and a 21-gene recurrence score (RS) of 11-25, although there was some chemotherapy benefit in women