Real-world clinical and survival outcomes of patients with early relapsed triple-negative breast cancer from the ESME national cohort

Early metastatic relapse of triple-negative breast cancer (mTNBC) after anthracyclins and/or taxanes based (A/T) primary treatment represents a highly aggressive cancer situation requiring urgent characterisation and handling. Epidemio-Strategy-Medico-Economical-Metastatic Breast Cancer (ESME-MBC) database, a multicenter, national, observational cohort (NCT03275311) provides recent data on this entity. All ESME patients diagnosed between 2008 and 2020 with mTNBC occurring as a relapse after a systemic neoadjuvant/adjuvant taxane and/or anthracycline-based chemotherapy were included. Early relapses were defined by a metastatic diagnosis up to 12 months of the end of neo/adjuvant A/T chemotherapy. We assessed overall survival (OS) and progression-free-survival under first-line treatment (PFS1) by early versus late relapse (≥12 months). Patients with early relapse (N = 881, 46%) were younger and had a larger tumour burden at primary diagnosis than those with late relapses (N = 1045). Early relapse rates appeared stable over time. Median OS was 10.1 months (95% CI 9.3–10.9) in patients with early relapse versus 17.1 months (95% CI 15.7–18.2) in those with late relapse (adjusted hazard-ratio (aHR): 1.92 (95% CI 1.73–2.13); p