ERBB2 and breast cancer: A randomized, phase 3 trial in which olaparib monotherapy was compared with standard therapy in patients with a germline BRCA mutation and human epidermal growth factor receptor type 2 (HER2)-negative metastasis breast cancer, detected a longer progression-free survival (PFS) of 7.0 months in the olaparib group than the 4.2 months (HR = 0.58, 95%CI: 0.43–0.80, p<.001), but no statistically significant improvement in OS [46,47].