A genotype-directed clinical trial is currently ongoing at our institution and other academic centers to determine the efficacy of PARP inhibition in somatic cfDNA BRCA1/2-mutant metastatic breast cancer [11], and the results of this trial may help expand the population of patients who benefit from PARP inhibitors, similar to what has been observed in ovarian cancer. Here, BRCA1 is linked to ovarian carcinoma.