Women's College Research Institute, Women's College Hospital and the Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
Prev Med. 2011 Sep;53(3):127-30. doi: 10.1016/j.ypmed.2011.06.017. Epub 2011 Jul 1.
A woman may be at high risk of breast cancer because of a strong family history of breast cancer or because she carries a mutation in the BRCA1 or BRCA2 gene. The annual risk for women in this category is between 1% and 2% and the lifetime risk of breast cancer among gene carriers may approach 80%. Several recent trials have reported that the sensitivity of MRI for imaging breast cancer greatly exceeds that of conventional mammography, but no study has yet determined that annual MRI reduces breast cancer-specific mortality. Women with breast cancer and a BRCA1 mutation typically develop aggressive breast cancers and the prognosis is relatively poor for women with small node-negative breast cancers (compared to non-carriers) in particular, if chemotherapy is not given. It is hoped that annual MRI screening combined with appropriate treatment will result in decreased mortality for this and other groups of high-risk women. MRI-based screening for women at moderate risk is a topic of great interest--MRI has not yet been endorsed in moderate risk women because of the high cost of screening and because the specificity of the screening test is not yet determined in this subgroup.
一位女性可能由于强烈的乳腺癌家族史或携带 BRCA1 或 BRCA2 基因突变而处于较高的乳腺癌风险中。此类女性的年度乳腺癌风险在 1%至 2%之间，而基因携带者的终身乳腺癌风险可能接近 80%。几项最近的试验报告称，MRI 对乳腺癌成像的敏感性大大超过传统的乳房 X 线摄影术，但尚无研究确定每年进行 MRI 检查可降低乳腺癌特异性死亡率。具有 BRCA1 基因突变的乳腺癌女性通常会发展为侵袭性乳腺癌，对于特别是无淋巴结转移的小乳腺癌患者（与非携带者相比），预后相对较差，如果未给予化疗。人们希望每年进行 MRI 筛查并结合适当的治疗，将降低此类高危女性和其他高危女性的死亡率。基于 MRI 的中度风险女性筛查是一个非常关注的话题——由于筛查成本高，并且在该亚组中尚未确定筛查试验的特异性，因此尚未在中度风险女性中批准 MRI。
