SWOG-S8814 — Prognostic and Predictive Value of the 21-Gene Recurrence Score Assay in Postmenopausal Women with Node-Positive, Estrogen-Receptor-Positive Breast Cancer on Chemotherapy

Phase 3 · 2010 · Breast Cancer

Design

Retrospective analysis of the randomized phase 3 SWOG-8814 trial using the 21-gene Recurrence Score to evaluate its prognostic and predictive value for CAF chemotherapy plus tamoxifen versus tamoxifen alone.

Population

Postmenopausal women with node-positive, estrogen-receptor-positive breast cancer.

Primary Endpoint

Disease-free survival by Recurrence Score group

Key Result

The 21-gene Recurrence Score predicted chemotherapy benefit: a high Recurrence Score (>=31) was associated with significant benefit from adding CAF chemotherapy (10-year DFS HR 0.59, 95% CI 0.35-1.01), whereas a low score (<18) showed no benefit (HR 1.02).

Guideline Impact

Supported incorporation of the 21-gene assay into ASCO/NCCN guidance for node-positive, ER-positive breast cancer (later confirmed by RxPONDER)