The application of PARPi was demonstrated to be successful in several tumor types [74, 75], but their efficacy has always been shown in comparison to the placebo, except for the phase III randomised OlympiAD trial (NCT02000622), where olaparib showed superiority in prolonging progression-free survival when compared to chemotherapy in BRCA mutated HER2 negative metastatic breast cancer [76]. Here, ERBB2 is linked to neoplasm.