Cancer Prevention Group, School of Cancer & Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London SE1 9RT, UK; Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK.
Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK; Department of Paediatrics, Sechenov University, Moscow, Russia.
Eur J Cancer. 2019 Aug;117:41-47. doi: 10.1016/j.ejca.2019.05.009. Epub 2019 Jun 21.
Breast density is a risk factor for breast cancer. As density changes across a woman's life span, we studied for how long a single density measurement taken in (post-)menopausal women remains informative.
We used data from Singaporean women who underwent a single mammography screen at age 50-64 years. For each case with breast cancer diagnosed at screening or in the subsequent 10 years, whether screen detected or diagnosed following symptoms, two age-matched controls were selected. We studied the excess risk of breast cancer, calculated as an odds ratio (OR) with conditional logistic regression and adjusted for body mass index, associated with 26-50% and with 51-100% density compared with ≤25% density by time since screening.
In total, 490 women had breast cancer, of which 361 were diagnosed because of symptoms after screening. Women with 51-100% breast density had an excess risk of breast cancer that did not seem to attenuate with time. In 1-3 years after screening, the OR was 2.22 (95% confidence interval [CI]: 1.07-4.61); in 4-6 years after screening, the OR was 4.09 (95% CI: 2.21-7.58), and in 7-10 years after screening, the OR was 5.35 (95% CI: 2.57-11.15). Excess risk with a stable OR of about 2 was also observed for women with 26-50% breast density. These patterns were robust when the analyses were limited to post-menopausal women, non-users of hormonal replacement therapy and after stratification by age at density measurement.
A single breast density measurement identifies women with an excess risk of breast cancer during at least the subsequent 10 years.
乳腺密度是乳腺癌的一个风险因素。由于女性在其生命周期中乳腺密度会发生变化，我们研究了在（绝经后）女性中单次乳腺密度测量结果在多长时间内保持信息性。
我们使用了在新加坡进行的 50-64 岁女性单次乳房 X 线筛查的数据。对于在筛查或随后 10 年内诊断为乳腺癌的每个病例，无论是否为筛查检出或症状诊断后诊断，均选择了 2 名年龄匹配的对照。我们通过时间从筛查开始，研究了与 ≤25%密度相比，26-50%密度和 51-100%密度与乳腺癌的风险比（OR），并使用条件逻辑回归进行了调整，以调整体重指数的影响。与乳腺癌相关。
共有 490 名女性患有乳腺癌，其中 361 名是因为筛查后的症状而诊断出的。51-100%乳腺密度的女性乳腺癌的超额风险似乎不会随着时间的推移而减弱。在筛查后 1-3 年内，OR 为 2.22（95%置信区间[CI]：1.07-4.61）；在筛查后 4-6 年内，OR 为 4.09（95%CI：2.21-7.58），在筛查后 7-10 年内，OR 为 5.35（95%CI：2.57-11.15）。对于 26-50%乳腺密度的女性，也观察到了稳定 OR 约为 2 的超额风险。当分析仅限于绝经后女性、激素替代疗法非使用者以及按密度测量时的年龄分层时，这些模式是稳健的。
单次乳腺密度测量可确定至少在随后 10 年内患有乳腺癌风险增加的女性。
