Assessment of 25-Year Survival of Women With Estrogen Receptor–Positive/<i>ERBB2</i>-Negative Breast Cancer Treated With and Without Tamoxifen Therapy

Abstract

This secondary analysis of data from the STO-3 clinical trial indicated that, among the selected subgroup of patients, tumor size followed by tumor grade were the markers most significantly associated with long-term survival. Furthermore, a significant long-term tamoxifen treatment benefit was observed among patients with larger tumors, lower tumor grades, and PR-positive tumors.