Abstract PS5-03-04: Timing of final oncologist visit and systemic treatment use near the end of life in advanced triple-negative breast cancer: a multinational cohort study

Abstract Background: Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer (BC) characterized by rapid clinical progression. Further lines of palliative systemic therapy typically offer diminishing benefit and increasing toxicity. Unlike hormone receptor-positive BC, TNBC lacks low-toxicity, long-term treatment options. In heavily pretreated patients, the decision to continue systemic therapy is particularly challenging. In the absence of robust evidence and amid growing expectations for individualized, patient-centered care, clinicians must rely on judgment to determine when to shift focus to palliative care. Timely recognition of the end-of-life (EOL) phase is essential to avoid overtreatment, reduce harm, and ensure care aligns with patient goals. The aim of this study was to assess the timing of the final oncologist visit relative to death in heavily pretreated women with advanced TNBC. We also analyzed systemic treatment status and palliative care involvement at that time and explored clinical factors associated with this interval. Materials and Methods: This multinational ambispective cohort study included women with advanced TNBC 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 (in days) between the final oncologist visit and death. Collected variables included age at last visit, number of prior chemotherapy lines, performance status (PS), systemic treatment continuation, and palliative care involvement prior to last visit. Analyses were performed in R (v4.3.3), with significance set at p < 0.05. Results: A total of 183 women were included. The median age at death was 53.6 years (range: 28.6-86.5). The median number of previous palliative chemotherapy lines was 4 (range: 2-12), and the median interval between the last oncologist consultation and death was 17 days (range: 0-410). At the final visit, systemic treatment was ongoing in 53 patients (29.5%), and palliative care involvement prior to the last visit was documented in 89 patients (49%). The median interval between the final oncologist consultation and death among patients continuing systemic therapy was 27 days (range: 2-194). PS at the last visit was 0-1 in 36 patients (20%), 2 in 38 (21%), 3 in 65 (36%), and 4 in 35 (19%). A significantly longer interval between the last visit and death was observed in patients with better performance status 0-1 vs ≥2 (p<0.001). No significant difference was observed with respect to palliative care involvement (p=0.849). Conclusions: These findings highlight the need for earlier recognition of clinical decline and more proactive integration of palliative care in patients with advanced TNBC. Avoiding non-beneficial systemic therapy near the EOL may support care focused on symptom relief, patient autonomy, and quality of life. Given the particularly poor prognosis of metastatic TNBC, ensuring timely access to appropriate EOL care has become a recognized priority at the European level, including within the Network of Expertise on Complex and Poor Prognosis Cancers (NoE PPC), as part of broader efforts to address inequalities and improve outcomes for this high-risk population. Structured EOL planning remains a critical gap in international real-world practice and requires urgent attention in this context. Citation Format: J. Zubrowska, M. Holanek, M. Pieniazek, A. Polakiewicz-Gilowska, R. Soumarova, H. Studentova, A. Konieczna, A. Mlodzinska, K. Winsko-Szczesnowicz, M. Lisik-Habib, A. Pekala, D. Krejci, J. Sustr, I. Kolarova, I. Danielewicz, M. Szymanik-Resko, T. Ciszewski, L. Rusinova, B. Czartoryska-Arlukowicz, A. Lacko, M. Jarzab, R. Pacholczak-Madej, I. Lugowska, Z. Bielcikova, M. Malejcikova, M. Puskulluoglu. Timing of final oncologist visit and systemic treatment use near the end of life in advanced triple-negative breast cancer: a multinational cohort study [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 PS5-03-04.