Abstract 241P
Background
As Japan faces a rapidly aging population, the mortality rate from breast cancer among the elderly population is increasing despite significant advances in therapeutic options. Elderly patients frequently do not receive standard treatments, often due to declines in physical and cognitive functions. We investigate the differences in treatment patterns and outcomes between elderly and younger patients with metastatic breast cancer.
Methods
We analyzed clinical data from the Advanced Breast Cancer Database (ABCD), maintained by the Japanese Breast Cancer Research Group. The dataset included patients registered between June 1, 2020, and October 31, 2023, encompassing clinicopathologic information such as primary or metastatic subtype, age at diagnosis of metastasis, comorbidities, sites of metastasis, treatment specifics and duration, and overall survival (OS).
Results
The study analyzed 1745 patients, with an average age at metastasis diagnosis of 60.3 years; of these, 331 (19%) were aged between 70 and 79 years, and 82 (4.7%) were 80 or older. Subtype distribution was 61% luminal, 11% luminal-HER2, 7% HER2, and 12% triple-negative breast cancer. During a median follow-up of 28.8 months, 448 deaths (26%) were observed. The three-year OS rate was notably lower at 56% for patients aged 80 and above. Among older people, there was a significant reduction in the use of intravenous treatments, BRCA analysis, and genomic panel testing. In multivariate analysis, no age-related differences were observed in the time to subsequent therapy for the first-line systemic treatment. However, OS for patients over 80 was significantly shorter than those under 80 (adjusted Hazard Ratio: 1.79, 95%CI: 1.09-2.97, p=0.02). Detailed findings will be discussed.
Conclusions
Our investigation sheds light on the disparities in treatment patterns and outcomes for elderly metastatic breast cancer patients. Despite treatment advancements, significant gaps in accessing standard care for older people due to age-related declines remain. Targeted efforts are necessary to enhance care for this vulnerable population, with further research and interventions needed to improve outcomes and quality of life.
Legal entity responsible for the study
This study is an observational study without intervention, utilizing existing data. It does not include any personally identifiable information. It falls under the ethical guidelines for life sciences and medical research involving human subjects in Japan and has been approved by the institution's Institutional Review Board (IRB).
Funding
Has not received any funding.
Disclosure
R. Mitsueda: Financial Interests, Personal, Invited Speaker: Eli Lilly. N. Niikura: Financial Interests, Personal, Invited Speaker: AstraZeneca, Pfizer, Daiichi Sankyo, Chugai, Eli Lilly, MSD; Financial Interests, Personal and Institutional, Research Grant: Chugai, Eisai, Nippon Kayaku; Financial Interests, Personal and Institutional, Invited Speaker: Daiichi Sankyo. S. Ohno: Financial Interests, Personal, Invited Speaker: MSD, Chugai, Lilly, Nippon Kayaku. T. Taira: Financial Interests, Personal, Invited Speaker: Chugai, Eli Lily, MSD, Pfizer, Daiichi Sankyo. M. Takada: Financial Interests, Personal, Invited Speaker: AstraZeneca, Daiichi Sankyo, Taiho, Chugai, MSD, Pfizer, Chugai, Lilly, Eisai; Financial Interests, Institutional, Invited Speaker: Daiichi Sankyo, AstraZeneca, Chugai, IQVIA, JBCRG, KBCRN, ABCSG; Financial Interests, Institutional, Research Grant: Eisai, Yakult, Medbis, Guardant Health Japan. M. Miyashita: Financial Interests, Personal, Invited Speaker: Chugai pharma, AstraZeneca, Eli Lily, Pfizer, MSD, Taiho Parma, Daiichi Sankyo, Eisai. H. Ishiguro: Financial Interests, Personal, Invited Speaker: Eisai, Chugai Pharmaceutical, Daiichi Sankyo, Taiho Pharmaceutical, Kyowa Kirin, Mitsubishi Tanabe Pharma, AstraZeneca, Ono Pharmaceutical; Financial Interests, Institutional, Research Grant: Eisai, Daiichi Sankyo, Takeda Pharmaceutical, Chugai Pharmaceutical, AstraZeneca, MSD, NIPRO . N. Masuda: Financial Interests, Personal, Invited Speaker: Chugai, AstraZeneca, Eisai, Eli Lilly, Pfizer, Dai-ichi Sankyo; Financial Interests, Institutional, Invited Speaker: AstraZeneca, Chugai, Daiichi Sankyo, Eisai, Eli Lilly, Kyowa-Kirin, MSD, Novartis, Pfizer, Sanofi, Ono Pharma; Non-Financial Interests, Member of Board of Directors: Japan Breast Cancer Research Group, Japanese Breast Cancer Society. S. Saji: Financial Interests, Personal, Invited Speaker: Eli Lilly, Chugai, AstraZeneca, Kyowa Kirin, Daiichi Sankyo, Taiho, Pfizer, MSD, Novartis, Eisai, Ono, Takeda, Exact Sciences; Financial Interests, Personal, Advisory Board: Gilead; Financial Interests, Institutional, Research Grant: Taiho, Chugai, Daiichi Sankyo; Financial Interests, Institutional, Invited Speaker: MSD, Daiichi Sankyo, Chugai, AstraZeneca, Sanofi, Gilead, Eli Lilly; Non-Financial Interests, Member of Board of Directors: Japanese Breast Cancer Society, Japanse Society of Medical Oncology, Japan Breast Cancer Research Group, Breast International Group. Y. Sagara: Financial Interests, Personal, Invited Speaker: Pfizer, Daiichi Sankyo, Eli Lilly, MSD, AstraZeneca, Eisai, Chugai, Nihon Kayaku, AstraZeneca. All other authors have declared no conflicts of interest.