Advancing breast cancer research through real-world data from the Singapore Joint Breast Cancer Registry.

Background: The Joint Breast Cancer Registry (JBCR) was established to collect comprehensive real-world data on patients with breast cancer treated across multiple institutions in Singapore. We present an overview of the registry, its structure, processes, and research findings. Patients and methods: JBCR includes all breast cancer patients aged ≥21 years old, treated in Singapore from 1980 onwards. Information on patient demographics, tumour characteristics, treatment, toxicity, and clinical outcomes is collected. We integrate data collection into clinical workflows, use automation, such as text-mining, and implement quality control processes to improve the accuracy and completeness of the registry. We further describe data security and governance processes that safeguard patients' privacy and allow for data sharing for research purposes. Results: A diverse cohort of over 35 000 patients have been enrolled in the registry from participating institutions across Singapore. The median age at diagnosis is 54 years with a median follow-up time of 7.6 years. About a quarter of the 8883 deaths were attributed to breast cancer. Analyses of JBCR data have revealed findings such as the impact of tumour subtypes on survival, disparities in treatment responses, and the novel role of radiomics in predicting chemotherapy response. We have also identified significant ethnic and socioeconomic disparities in breast cancer outcomes, emphasizing the need for targeted interventions. Conclusion: By leveraging real-world data, JBCR provides insights into the treatment trends and long-term outcomes of breast cancer in Singapore. We provide value to various stakeholders in clinical care, research, and policy-making. Future initiatives seek to address current limitations, including expanding the collection of genetic and molecular data, increasing patient-reported quality-of-life measures, and enhancing international collaborations.