Risk Assessment, Genetic Counseling, and Genetic Testing for<i>BRCA-</i>Related Cancer in Women
Authors: Heidi D. Nelson, Miranda Pappas, Amy Cantor, Elizabeth Haney, Rebecca Holmes
Journal: JAMA (2019)

<h3>Importance</h3> Pathogenic mutations in breast cancer susceptibility genes<i>BRCA1</i>and<i>BRCA2</i>increase risks for breast, ovarian, fallopian tube, and peritoneal cancer in women; interventions reduce risk in mutation carriers. <h3>Objective</h3> To update the 2013 US Preventive Services Task Force review on benefits and harms of risk assessment, genetic counseling, and genetic testing for<i>BRCA1/2</i>-related cancer in women. <h3>Data Sources</h3> Cochrane libraries; MEDLINE, PsycINFO, EMBASE (January 1, 2013, to March 6, 2019, for updates; January 1, 1994, to March 6, 2019, for new key questions and populations); reference lists. <h3>Study Selection</h3> Discriminatory accuracy studies, randomized clinical trials (RCTs), and observational studies of women without recently diagnosed<i>BRCA1/2</i>-related cancer. <h3>Data Extraction and Synthesis</h3> Data on study methods, setting, population characteristics, eligibility criteria, interventions, numbers enrolled and lost to follow-up, outcome ascertainment, and results were abstracted. Two reviewers independently assessed study quality. <h3>Main Outcomes and Measures</h3> Cancer incidence and mortality; discriminatory accuracy of risk assessment tools for<i>BRCA1/2</i>mutations; benefits and harms of risk assessment, genetic counseling, genetic testing, and risk-reducing interventions. <h3>Results</h3> For this review, 103 studies (110 articles; N = 92 712) were included. No studies evaluated the effectiveness of risk assessment, genetic counseling, and genetic testing in reducing incidence and mortality of<i>BRCA1/2</i>-related cancer. Fourteen studies (n = 43 813) of 8 risk assessment tools to guide referrals to genetic counseling demonstrated moderate to high accuracy (area under the receiver operating characteristic curve, 0.68-0.96). Twenty-eight studies (n = 8060) indicated that genetic counseling was associated with reduced breast cancer worry, anxiety, and depression; increased understanding of risk; and decreased intention for testing. Twenty studies (n = 4322) showed that breast cancer worry and anxiety were higher after testing for women with positive results and lower for others; understanding of risk was higher after testing. In 8 RCTs (n = 54 651), tamoxifen (relative risk [RR], 0.69 [95% CI, 0.59-0.84]; 4 trials), raloxifene (RR, 0.44 [95% CI, 0.24-0.80]; 2 trials), and aromatase inhibitors (RR, 0.45 [95% CI, 0.26-0.70]; 2 trials) were associated with lower risks of invasive breast cancer compared with placebo; results were not specific to mutation carriers. Mastectomy was associated with 90% to 100% reduction in breast cancer incidence (6 studies; n = 2546) and 81% to 100% reduction in breast cancer mortality (1 study; n = 639); oophorectomy was associated with 69% to 100% reduction in ovarian cancer (2 studies; n = 2108); complications were common with mastectomy. <h3>Conclusions and Relevance</h3> Among women without recently diagnosed<i>BRCA1/2</i>-related cancer, the benefits and harms of risk assessment, genetic counseling, and genetic testing to reduce cancer incidence and mortality have not been directly evaluated by current research.