In the field of gynecology, the approval of the PARP inhibitors (PARPi) has been changing the treatment of ovarian cancer patients. The BRCA genetic test and the HRD test are being used as a companion diagnosis before starting PARPi treatment. BRACAnalysis CDx® and Myriad myChoice® HRD test are widely used as a BRCA genetic test and HRD test, respectively. In addition, FoundationOne®CDx is sometimes used as a tumor BRCA test and HRD test. In clinical practice, gynecologists treating ovarian cancer are faced with making decisions such as whether to recommend the gBRCA test to all ovarian cancer patients, whether to perform the gBRCA test first or HRD test first, and so on. Regarding the judgment result of the HRD test, the cutoff value differs depending on the clinical trial, and the prevalence of gBRCA pathogenic variant rate is different in each histological type and country. A prospective cohort study showed that RRSO reduced all-cause mortality in both pre- and postmenopausal women; however, RRSO significantly reduced the risk of breast cancer for BRCA2 pathogenic variant carriers, but not for BRCA1 pathogenic variant carriers. Moreover, salpingectomy alone is said to not decrease the risk of developing ovarian or breast cancer, so further discussion is evidently required. We discuss the current situation and problems in doing BRCA genetic test and RRSO in this review article.
Keywords: BRCA1/2; PARP inhibitor; companion diagnosis; hereditary breast and ovarian cancer; homologous recombination deficiency; risk-reducing salpingo-oophorectomy.