Outcomes Of Metastatic Castration Resistant Prostate Cancer (Mcrpc) Patients With Dna Repair Germline Mutations (Gddr) Following First Taxane-Based Treatment.

247Background: Germline DDR have been identified in up to 12% of mCRPC patients. Initial results from various retrospective series have reported discordant impact in clinical outcomes associated to these gDDR following conventional treatments. PROREPAIR-B (Castro et al ESMO 2017) is the first prospective study to address this question. In this planned sub-analysis, we report mCRPC treatment outcomes associated to taxanes. Methods: PROREPAIR-B (NCT03075735) is a prospective multicentre observational cohort study. Patients diagnosed with mCRPC, with unknown mutational status at study entry and who were going to start a first-line treatment for mCRPC were eligible. For this sub-analysis patients who received docetaxel or cabazitaxel as first-taxane were selected. The endpoints of this sub-analysis included to assess the impact of BRCA1, BRCA2, ATM and PALB2 and other gDDR on cause-specific survival (CSS), progression free survival (PFS), time to PSA progression (bPFS) and response to the first administered t...