The current landscape of molecular profiling in the treatment of epithelial ovarian cancer.

• All women with ovarian cancer should be offered germline testing for BRCA mutations and other cancer susceptibility genes • Patients with deleterious BRCA mutations should be offered frontline maintenance therapy with a PARP inhibitor • Assays for homologous recombination deficiency may guide treatment options in patients without a deleterious BRCA mutation • Tumor molecular profiling may identify targeted therapies for off-label use in patients with limited treatment options Advances in next generation sequencing have allowed for rapid and economical germline and tumor genomic profiling. Targeted therapies based on molecular tumor profiling are now integrated into treatment guidelines for many solid tumors. In epithelial ovarian cancer, 50% of tumors possess damaging mutations in homologous recombination repair genes (aka homologous recombination deficiency or HRD) which includes the BRCA genes. Deleterious BRCA mutations and HRD have recently emerged as predictive biomarkers for the use of PARP inhibitors in ovarian cancer. Every patient with ovarian cancer must be referred for genetic counseling and germline testing for BRCA mutations. Multigene panel genetic testing may be more informative and cost-effective than limited testing of cancer susceptibility genes. Patients without a germline deleterious BRCA mutation must be assessed for a somatic BRCA mutation. Assays for HRD may help guide treatment options in women who do not have a BRCA mutation. Currently, all patients with a germline or somatic BRCA mutation should be offered upfront maintenance therapy with a PARP inhibitor. During May 2020, options for maintenance therapy with a PARP inhibitor were expanded to patients with HRD and HR-proficient tumors. [ABSTRACT FROM AUTHOR]