BRCA1 and breast cancer: Although the efficacy of olaparib in the treatment of recurrent BC has been demonstrated in the OlympiAD trial and other studies [8,9], perhaps for the low frequency (1.2% to 8.8%) of cases with BRCA1/2 PV among metastatic recurrent BC patients [1], there is no comprehensive real-world assessment in terms of its efficacy and safety.