Centre for Molecular, Environmental, Genetic and Analytical Epidemiology, The University of Melbourne, School of Population Health, L1 723 Swanston St, Carlton, Victoria, 3010, Australia.
Breast Cancer Res Treat. 2010 Nov;124(2):551-4. doi: 10.1007/s10549-010-0976-y. Epub 2010 Jun 11.
Mammographic density is a strong risk factor for breast cancer. Which and how many x-rays are used for research, and how mammographic density is measured varies across studies. In this article, we compared three different measurements (absolute dense area, percent dense area and percent dense volume) from each of four mammograms [left, right, medio-lateral oblique (MLO) and cranio-caudal (CC) views] using three different methods of measurement [computer-assisted thresholding, visual assessment and standard mammogram form (SMF)] to investigate whether additional measurements and/or different methods of measurement provide more information in the prediction of breast cancer risk. Mammographic density was measured in all four mammograms from 318 cases and 899 age-matched controls combined from the Cambridge and Norwich Breast Screening Programmes. Measurements were averaged across various combinations of mammogram type and/or view. Conditional logistic regression was used to estimate odds ratios associated with increasing quintiles of each mammographic measure. Overall, there appeared to be no difference in the fit of the models using two or four mammograms compared to the models using just the contralateral MLO or CC mammogram (all P > 0.07) for all methods of measurement. Common practice of measuring just the contralateral MLO or CC mammogram for analysis in case-control studies investigating the association between mammographic density and breast cancer risk appears to be sufficient.
乳腺密度是乳腺癌的一个重要危险因素。用于研究的 X 射线的类型和数量，以及乳腺密度的测量方法在不同的研究中有所不同。在本文中，我们比较了来自 4 张乳房 X 光片（左侧、右侧、内外斜位（MLO）和头尾位（CC））的 3 种不同测量方法（绝对致密面积、百分比致密面积和百分比致密体积），这 3 种测量方法使用了 3 种不同的测量方法（计算机辅助阈值、视觉评估和标准乳房 X 光片表格（SMF）），以研究额外的测量和/或不同的测量方法是否能提供更多的乳腺癌风险预测信息。使用来自剑桥和诺维奇乳房筛查计划的 318 例病例和 899 例年龄匹配对照者的所有 4 张乳房 X 光片中的乳腺密度进行了测量。在各种类型和/或视图的乳房 X 光片组合之间对测量值进行了平均。条件逻辑回归用于估计与每个乳腺测量值递增五分位数相关的优势比。总体而言，与仅使用对侧 MLO 或 CC 乳房 X 光片的模型相比，使用 2 张或 4 张乳房 X 光片的模型（所有 P > 0.07）拟合度似乎没有差异，所有测量方法均如此。在研究乳腺密度与乳腺癌风险之间的关联的病例对照研究中，通常仅测量对侧 MLO 或 CC 乳房 X 光片进行分析的做法似乎已经足够。
