Aromatase Inhibitor Therapy Improves Long-Term Survival in HR-Positive, HER2-Positive Early Breast Cancer
Key Clinical Takeaways
- Aromatase inhibitors (AIs) were associated with significantly improved 10-year disease-free survival (80.1% vs 76.5%) and time to distant recurrence compared with estrogen receptor (ER) therapy in HR-positive, HER2-positive early breast cancer treated with chemotherapy and trastuzumab-based regimens.
- The DFS benefit of AIs was consistent across all evaluated patient subgroups, including by age, menopausal status, tumor characteristics, and anti-HER2 treatment arm.
- Among premenopausal patients, AI with or without ovarian function suppression yielded the highest 10-year DFS (90%), outperforming both ER therapy alone and in combination with ovarian function suppression, suggesting a potential role for ovarian suppression strategies in maximizing endocrine responsiveness.
Matteo Lambertini, MD, PhD, University of Genova - IRCCS Ospedale Policlinico San Martino, Genoa, Italy, discusses 10-year analysis results from the ALTTO trial evaluating the comparative effectiveness of aromatase inhibitors versus selective estrogen receptor modulators as adjuvant endocrine therapy among patients with centrally confirmed HR-positive, HER2-positive early breast cancer treated with modern chemotherapy and trastuzumab-based regimens.
Aromatase inhibitors demonstrated superior disease-free survival and time to distant recurrence across virtually all clinical subgroups, including both premenopausal and postmenopausal patients, with no significant difference in overall survival.
These findings were presented at the 2025 San Antonio Breast Cancer Symposium in San Antonio, Texas.
Source:
Lambertini M, Samy F, Agostinetto E, et al. Adjuvant aromatase inhibitor or tamoxifen in patients with hormone receptor-positive/HER2-positive early breast cancer: An exploratory analysis from the ALTTO (BIG 2-06) trial. Presented at SABCS 2025. December 9 - 12, 2025. San Antonio, Texas. Abstract GS1-03
