SABCS 2022: Long-Term Update From TAILORx in Early-Stage Breast Cancer

By: Emily Rhode
Posted: Thursday, December 8, 2022

Joseph Sparano, MD, FACP, of the Mount Sinai Health System, New York, and colleagues presented results from a long-term update of the TAILORx trial of adjuvant endocrine therapy versus chemotherapy plus endocrine therapy in patients with early-stage breast cancer and a 21-gene recurrence score (RS) of 11 to 25 at the 2022 San Antonio Breast Cancer Symposium (SABCS; Abstract GS1-05). The data described the additional invasive disease–free survival events that occurred up to 3.5 years after the original median follow-up of 7.5 years in the randomized and overall populations.

“The primary trial conclusions remain unchanged: Endocrine therapy was noninferior to chemotherapy plus endocrine therapy in the randomized group with a RS of 11 to 25. Although recurrence occurred in < 10% by 12 years for a RS of 0 to 25, late recurrence events beyond 5 years exceeded earlier recurrence. Nonrecurrence events occurred in about 13% at 12 years, contributing substantially to the [invasive disease–free survival] rates,” the study authors stated.

The study enrolled 10,253 women between April 2006 and October 2010. Eligible patients had hormone receptor–positive, HER2-negative, T1b–T2N0 early-stage breast cancer and agreed to have chemotherapy assigned or randomized depending on their RS. The primary endpoint in the primary analysis was invasive disease–free survival at a median follow-up of 7.5 years, whereas the primary endpoint in the updated analysis was invasive disease–free survival at a median follow-up of 11.0 years in the randomized population and 10.4 years in the overall population.

The 5-year invasive disease–free survival event rate with endocrine therapy (n = 3,399) was 92.8% versus 93.1% with chemotherapy plus endocrine (hazard ratio [HR] = 1.08; P = .26). The 12-year invasive disease–free survival event rate with endocrine therapy was 76.8% versus 77.4% with chemotherapy plus endocrine therapy (HR = 1.08). Less than 10% of patients had disease recurrence by 12 years. However, recurrence events beyond 5 years, considered late-recurrence events, exceeded earlier-recurrence rates.

Disclosure: For full disclosures of the study authors, visit sabcs.org.

2022 San Antonio Breast Cancer Symposium

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