The classic demonstration of synthetic lethality is the role of poly(ADP-ribose) polymerase inhibitors (PARPi) in cancers in which homologous recombination DNA repair (HRR) is defective (HRD), particularly in breast and ovarian cancers associated with germline BRCA1 and BRCA2 mutations [2]. This evidence concerns the gene BRCA1 and ovarian cancer.