Abstract ED01-01: Optimizing endocrine therapy in premenopausal women

Abstract Premenopausal women with early-stage hormone receptor (HR)-positive breast cancer are candidates for adjuvant endocrine therapy and have several treatment options. The clinical team should assess an individual woman’s risk of recurrence, estimate benefits from specific endocrine manipulations, and consider co-morbidities, adverse event profile and host factors. Risk stratification strategies including clinic-pathologic features, genomic assays and composite scores can guide recommendations regarding type and duration of endocrine therapy, in particular in node-negative disease. Adjuvant tamoxifen for 5 to 10 years significantly reduces breast cancer recurrence and death. Premenopausal women who are at high risk of recurrence benefit from ovarian function suppression (OFS) with tamoxifen or an aromatase inhibitor for 5 years. Those include women with high-risk clinico-pathological features and younger age, and for whom chemotherapy is commonly recommended. There are currently no available data regarding the use of extended OFS beyond 5 years. Newer data support the addition of CDK 4/6 inhibitors to endocrine therapy in women with high-risk disease. Endocrine therpay is associated with frequent bothersome and few significant side effects that can negatively impact quality of life and adherence to treatment. Clinicians must carefully weigh the benefits associated with specific endocrine therapies, and possible short- and long-term side effects to individualize therapy, and to consider interventions to enhance adherence. Citation Format: V. Stearns. Optimizing endocrine therapy in premenopausal women abstract. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr ED01-01.