Abstract PS1-02-21: Personalizing breast cancer treatment for older adults: use of the geriatric assessment in chemotherapy decision making

Abstract Purpose: To assess which patient characteristics and elements of the GeriatricAssessment (GA) are associated with not proceeding to chemotherapy in older womenwith breast cancer. Methods: Between April 2022 and February 2024, 50 women aged 65 and older with breastcancer were seen in the Cancer and Aging Interdisciplinary Team clinic at our institution forGA prior to initiating systemic treatment. We present characteristics among our cohort andevaluate differences in GA domains between patients who proceeded to chemotherapyand those who did not. Results: When comparing the cohort of patients who did not undergo chemotherapy vsthose who did, factors that were significantly associated with the decision to omitchemotherapy included older age (median 84 vs 75 years old, p<0.001), non-triple negativedisease (75% vs 42%, p=0.035), frailty (94% vs 55%, p=0.007), abnormal functionalperformance test (75% vs 19%, p<0.001), high risk CARG-TT score (50% vs 13%, p=0.007),chemotherapy not recommended by geriatrician (69% vs 0%, p<0.001), iADL dependency(88% vs 44%, p=0.047), KPS<80 (75% vs 19%, p=0.003), and limited social activity (100% vs52%, p=0.015). Of the women who proceeded to chemotherapy, 42% underwent upfrontchemotherapy modifications. Conclusion: Our study identified components of the GA associated with chemotherapydecisions and modifications in older women with breast cancer. Further research isneeded to determine the causal relationships between GA components and decision-making and evaluate how such decision-making could be improved. Citation Format: S. A. Roberts, A. L. Tin, J. Singh, D. Lake, E. Meditz, A. Kulkarni, M. Boparai, B. Korc-Grodzicki, A. Shahrokni, K. Alexander. Personalizing breast cancer treatment for older adults: use of the geriatric assessment in chemotherapy decision making [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS1-02-21.