Abstract Background Metastatic breast cancer (MBC) is an advanced stage of disease with a poor prognosis and heavy symptom burden. Its five-year relative survival rate is about 30%, and the median survival time is roughly 2-3 years. Palliative care can alleviate symptoms and improve quality of life in advanced cancer, and major oncology guidelines (ASCO/ESMO) now recommend providing specialized palliative care early in the course of metastatic illness. However, in real-world practice palliative care is often introduced very late. This study examines how delayed palliative care referral affects outcomes in MBC and makes the case for earlier integration. Methods We conducted a retrospective cohort study using data from the TriNetX global health research network, which includes de-identified electronic health records from multiple healthcare organizations, predominantly located in the United States. Female patients who were diagnosed with stage IV (metastatic) breast cancer between 2011 and 2024 were included. The primary focus of the analysis was to assess the time interval between metastatic diagnosis and receipt of a palliative care consultation. Additional variables collected included demographics and documented clinical symptoms. Patients were grouped based on whether or not they received a palliative care consultation, and matched cohort analysis was performed to compare symptom burden between the groups. Results A total of 1036 women with stage IV breast cancer were included. The median age was 66 years (range 30-90; SD = 13). The median time from metastatic diagnosis to first palliative care consult was 408 days, indicating that referrals generally occurred late in the disease course. Notably, median referral delays varied by race: 425 days for White patients, 347 days for Black or African American patients, 699 days for Asian patients, 294 days for Hispanic or Latino patients and 388 days for American Indian/Alaska Native patients. When we analyzed matched cohorts of patients who did and did not receive palliative care consultations, it was discovered that symptom burden was significantly higher in the palliative care group. This included symptoms such as pain, fatigue, delirium, and dyspnea. Conclusions These results highlight that palliative care is frequently introduced late for patients with metastatic breast cancer. Earlier integration, ideally soon after stage IV diagnosis, is advocated in guidelines and has the potential to improve symptom control, enhance quality of life, and align care with patient goals. In our cohort, the median time to palliative care referral was over a year from diagnosis. These findings align with prior studies and underscore that late palliative care referral may limit its impact on meaningful outcomes. The observed racial differences in timing further suggest a need to address systemic and cultural barriers to equitable, timely access. Additionally, the significantly higher symptom burden observed in the palliative care group supports the concern that referrals are often made reactively, in response to advanced clinical decline. Overall, our findings reinforce that palliative care should be embedded earlier in the treatment trajectory - not as a last resort, but as a concurrent component of comprehensive cancer Citation Format: D. Chelysheva, J. Fanizza, E. Nasrollahi, E. Aguilar Montoya. Delayed Palliative Care in Metastatic Breast Cancer: Rationale for Early Integration 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 PS1-02-22.
Chelysheva et al. (Tue,) studied this question.