Abstract P2-15-14: Triple negative (TNBC) metastatic breast cancer (MBC) patients (pts): Is chemotherapy (CHT) choice influenced by adjuvant (adj) treatments? Results from the GIM-13 AMBRA study

Background: TNBC shows a very bad prognosis: median time to relapse is 18 months and median overall survival (OS) is less than 24 months. Methods: AMBRA is a longitudinal cohort study, describing the choice of 1st- and subsequent treatments in HER2-ve MBC pts in the years 2012-2015. The present analysis is focused on TNBC pts (127 out of 879 evaluable; 14.4%) and CHT strategies, overall and according to adj treatment. Kaplan Meyer probability of survival from primary (DFS), 1st(PFS1) and 2nd(PFS2) progression and Time from last CHT and death were calculated for the whole population and according the main adj regimens. Results: Median age at primary diagnosis was 53 years. The most used regimens in the adj setting were anthra/taxane(tax) 50.7%, anthra 22.1% or others (CMF included) 20.6%. Median time to events was: DFS 23.2, PFS1 6.5 and PFS2 4.3 months, respectively. CHT choices in the metastatic setting according to adj treatment were: OS rates at 5 and 8 years from primary are 50% and 40%. OS rates from 1st progression are 50% and 20% at 22 and 40 months. Median OS (months) according to 1st line regimen was similar (ns) across the regimens (paclitaxel+bevacizumab: 17.8; Platinum-based: 14.1; CAPE/VRL: 16.3). Median time from last CHT and death was 1.5 months (29.6% Conclusion: Our results show that taxanes play a crucial role in MBC even if used in 50% of Adj. CAPE/VRL, Platinum regimens and Eribuline are also widely used. Time from last CHT administration and Death is very short in 30% of cases Citation Format: Giorgio Mustacchi, Alessandra Beano, Alessandra Fabi, Lorenzo Livi, Antonio Bernardo, Ferdinando Riccardi, Paolo Marchetti, Ornella Garrone, Lucrezia Diodati, Laura Biganzoli, Monica Giordano, Anna Turletti, Livio Blasi, Andrea Milani, Clara Natoli, Marta Riemma, Alessia D9Alonzo, Grazia Arpino, Paolo Pronzato, Marina E Cazzaniga, on behalf of GIM-13 AMBRA Study Group. Triple negative (TNBC) metastatic breast cancer (MBC) patients (pts): Is chemotherapy (CHT) choice influenced by adjuvant (adj) treatments? Results from the GIM-13 AMBRA study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-15-14.