A retrospective population cohort study was conducted to characterize Chilean patients with early hormone receptor (HR)-positive breast cancer in young women, focusing on the use of ovarian function suppression (OFS) and the predictive utility of the Regan Composite Risk (RCR) score.
The study included HR-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer patients who were treated between 2001 and 2021 and were aged ≤35 years. Key analyses encompassed clinicopathological characteristics, treatment strategies, and survival outcomes. Furthermore, these analyses evaluated the predictive value of RCR scores in clinical practice.
Of 4860 early-stage HR-positive/HER2-negative cases, 143 (2.9%) met the inclusion criteria. Patients predominantly presented with stage II-III disease with a median age of 31 years. While the majority received adjuvant chemotherapy (CT) and endocrine therapy (ET), only 18% received OFS, mainly through surgical oophorectomy.
Although the 5-year overall survival (OS) rate was 88.7%, recurrence rates were also notably high, emphasizing the aggressive nature of breast cancer in young women. The study revealed higher RCR scores in patients treated with CT plus ET compared with ET as an independent treatment option. Similarly, patients receiving OFS had significantly higher RCR scores than those on tamoxifen alone.
Higher RCR scores were associated with poorer OS, irrespective of treatment received. Despite the observed benefits of OFS in clinical trials, its utilization in the Chilean cohort was limited, possibly due to cost, availability, and concerns about long-term side effects.
The study confirms the RCR score as a valuable prognostic tool for identifying high-risk young women with breast cancer who may benefit from OFS. However, disparities exist between international guidelines and real-world practice in Chile regarding OFS utilization. The findings underscore the need for strategies to improve the adoption of evidence-based treatments like OFS to optimize outcomes.
Limitations include the study’s retrospective nature, potential underestimation of OFS utilization, and lack of data on post-treatment fertility. Future efforts should focus on addressing barriers to OFS implementation and further understanding the unique needs of young women with breast cancer to enhance treatment strategies and improve outcomes.1
References
- Heredia A, Walbaum B, Vidal M, et al. Suboptimal use of ovarian function suppression in very young women with early breast cancer: a real-world data study. Breast Cancer Res Treat. 2024;203:173-179.
