Key clinical point: Aromatase inhibitor vs. tamoxifen reduced the risk for breast cancer (BC) recurrence in premenopausal women with early-stage, estrogen receptor-positive (ER+) BC receiving ovarian suppression.
Major finding: Aromatase inhibitor vs. tamoxifen was associated with significantly reduced rates of BC recurrence during the first 4 years of follow-up (risk ratio [ RR] 0.68; P < .0001) and distant recurrence (RR 0.83; P = .018). No significant differences in breast cancer mortality, death without recurrence, or all-cause mortality were observed between the treatment groups.
Study details: Findings are a meta-analysis of 4 phase 3 trials ( ABCSG-XII, TEXT, SOFT, and HOBOE) including 7,030 premenopausal women with ER + BC who were randomly assigned to aromatase inhibitors (anastrozole, exemestane, or letrozole) or tamoxifen for 3 or 5 years, all in combination with ovarian suppression or ablation.
Disclosures: This study was funded by the Cancer Research UK and UK Medical Research Council. The authors declared serving as leaders and fiduciaries or receiving grants, consulting fees, travel support, or honoraria from several sources.
Source: Early Breast Cancer Trialists' Collaborative Group . Lancet Oncol. 2022 (Feb 3). Doi: 10.1016/S1470-2045(21)00758-0.