Polygenic factors are estimated to account for an additional 18% of the familial relative risk of breast cancer, with those at the highest level of polygenic risk distribution having a least a twofold increased risk of the disease. Polygenic testing promises to revolutionize health services by providing personalized risk assessments to women at high-risk of breast cancer and within population breast screening programs. However, implementation of polygenic testing needs to be considered in light of its current limitations, such as limited risk prediction for women of non-European ancestry. This article aims to provide a comprehensive review of the evidence for polygenic breast cancer risk, including the discovery of variants associated with breast cancer at the genome-wide level of significance and the use of polygenic risk scores to estimate breast cancer risk. We also review the different applications of this technology including testing of women from high-risk breast cancer families with uninformative genetic testing results, as a moderator of monogenic risk, and for population screening programs. Finally, a potential framework for introducing testing for polygenic risk in familial cancer clinics and the potential challenges with implementing this technology in clinical practice are discussed.

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多基因乳腺癌风险的临床应用：新兴领域的重要评论和观点

据估计，多基因因素占乳腺癌家族相对风险的18％，而多基因风险分布水平最高的人患该疾病的风险至少增加了两倍。多基因检测有望通过为处于乳腺癌高风险和人群乳腺筛查计划中的妇女提供个性化的风险评估，来彻底改变医疗服务。但是，有鉴于其当前的局限性（例如，对非欧洲血统的妇女的风险预测有限），需要考虑实施多基因检测。本文旨在提供有关多基因乳腺癌风险的证据的全面综述，包括在全基因组意义上发现与乳腺癌相关的变异体，以及使用多基因风险评分评估乳腺癌风险。我们还回顾了该技术的不同应用，包括对高危乳腺癌家庭的妇女进行测试（其结果无资料），作为单基因风险的调节剂以及用于人群筛查的程序。最后，讨论了在家庭癌症诊所中引入多基因风险测试的潜在框架，以及在临床实践中实施该技术的潜在挑战。以及人口普查计划。最后，讨论了在家庭癌症诊所中引入多基因风险测试的潜在框架，以及在临床实践中实施该技术的潜在挑战。以及人口普查计划。最后，讨论了在家庭癌症诊所中引入多基因风险测试的潜在框架，以及在临床实践中实施该技术的潜在挑战。