Abstract
BACKGROUND: In heavily pretreated patients with metastatic triple-negative breast cancer (mTNBC), further systemic therapy offers limited benefit and increased toxicity. Recognizing the end-of-life (EOL) phase in time helps avoid overtreatment and ensure goal-concordant care. This study analyzed the interval between the last oncologist visit and death in pretreated women with mTNBC, as well as systemic therapy status, palliative care involvement and related factors. METHODS: This multinational ambispective cohort study included women with mTNBC who received ≥2 lines of palliative systemic therapy and died between June 20, 2022 and June 20, 2025. Data from 17 centers in Poland, the Czech Republic and Slovakia were extracted from medical records. The primary endpoint was the interval between the final oncologist visit and death. RESULTS: 183 women with median age at death 53.6 years (28.6-86.5) were included. Patients had a median of 4 prior palliative chemotherapy lines (2-12) and the median interval from last oncologist visit to death was 17 days (0-410). At the final visit, 29.5 % continued systemic therapy and 49 % had prior palliative care involvement. Longer intervals were associated with PS 0-1 vs ≥ 2 (p = 0.005), while palliative care involvement had no significant effect (p = 0.849). CONCLUSIONS: The results highlight the need for earlier recognition of clinical decline and timely palliative care in mTNBC. Limiting non-beneficial systemic therapy near EOL supports symptom control, autonomy, and quality of life. Despite European efforts, including the Network of Expertise on Complex and Poor Prognosis Cancers, structured EOL planning remains a major gap.