Centre for Genetic Origins of Health and Disease, Curtin University and The University of Western Australia, 35 Stirling Highway, M409, Perth, WA, 6009, Australia.
BreastScreen Western Australia, Women and Newborn Health Service, 9th Floor, Eastpoint Plaza, 233 Adelaide Terrace, Perth, WA, 6000, Australia.
Breast Cancer Res Treat. 2019 Jul;176(1):235-242. doi: 10.1007/s10549-019-05225-9. Epub 2019 Apr 12.
Mammographic density is an established breast cancer risk factor within many ethnically different populations. The distribution of mammographic density has been shown to be significantly lower in Western Australian Aboriginal women compared to age- and screening location-matched non-Aboriginal women. Whether mammographic density is a predictor of breast cancer risk in Aboriginal women is unknown.
We measured mammographic density from 103 Aboriginal breast cancer cases and 327 Aboriginal controls, 341 non-Aboriginal cases, and 333 non-Aboriginal controls selected from the BreastScreen Western Australia database using the Cumulus software program. Logistic regression was used to examine the associations of percentage dense area and absolute dense area with breast cancer risk for Aboriginal and non-Aboriginal women separately, adjusting for covariates.
Both percentage density and absolute dense area were strongly predictive of risk in Aboriginal women with odds per adjusted standard deviation (OPERAS) of 1.36 (95% CI 1.09, 1.69) and 1.36 (95% CI 1.08, 1.71), respectively. For non-Aboriginal women, the OPERAS were 1.22 (95% CI 1.03, 1.46) and 1.26 (95% CI 1.05, 1.50), respectively.
Whilst mean mammographic density for Aboriginal women is lower than non-Aboriginal women, density measures are still higher in Aboriginal women with breast cancer compared to Aboriginal women without breast cancer. Thus, mammographic density strongly predicts breast cancer risk in Aboriginal women. Future efforts to predict breast cancer risk using mammographic density or standardize risk-associated mammographic density measures should take into account Aboriginal status when applicable.
在许多不同种族的人群中，乳腺密度是乳腺癌的一个既定风险因素。与年龄和筛查地点相匹配的非土著女性相比，西澳大利亚州土著女性的乳腺密度分布明显较低。乳腺密度是否是土著女性乳腺癌风险的预测因素尚不清楚。
我们使用 Cumulus 软件程序，从 BreastScreen Western Australia 数据库中选择的 103 名土著乳腺癌病例和 327 名土著对照、341 名非土著病例和 333 名非土著对照中测量了乳腺密度。使用逻辑回归分别检查了百分比密度区和绝对密度区与土著和非土著女性乳腺癌风险的关联，调整了协变量。
在土著女性中，百分比密度和绝对密度区均与风险高度相关，调整后的标准偏差（OPERAS）分别为 1.36（95%CI 1.09,1.69）和 1.36（95%CI 1.08,1.71）。对于非土著女性，OPERAS 分别为 1.22（95%CI 1.03,1.46）和 1.26（95%CI 1.05,1.50）。
虽然土著女性的平均乳腺密度低于非土著女性，但患有乳腺癌的土著女性的密度测量值仍高于没有乳腺癌的土著女性。因此，乳腺密度强烈预测了土著女性的乳腺癌风险。未来使用乳腺密度预测乳腺癌风险或标准化与风险相关的乳腺密度测量值的努力，在适用的情况下应考虑到土著身份。
