Abstract
Hereditary breast and ovarian cancer (HBOC) is a familial neoplastic syndrome that frequently develops as both breast and ovarian cancer. Mutations of BRCA1 and BRCA2 genes have been identified as the cause of HBOC. Poly ADP-ribose polymerase (PARP) inhibitors have attracted attention as novel therapeutic agents for cancers with BRCA mutation. In 2014, olaparib was approved by the FDA as the first PARP inhibitor, and many clinical studies of PARP inhibitors are in progress. With "BRCAness", a homologous recombination deficiency, PARP inhibitors have also recently been shown to be effective for cancer without BRCA1/2 mutation. The HRD score has been proposed to be a useful indicator for BRCAness. These results suggest that PARP inhibitors are likely to extend the application range and efficacy of tailor-made treatment.
