The distribution and determinants of mammographic density measures in Western Australian aboriginal women

Abstract

Background Mammographic density (MD) is an established risk factor for breast cancer. There are significant ethnic differences in MD measures which are consistent with those for corresponding breast cancer risk. This is the first study investigating the distribution and determinants of MD measures within Aboriginal women of Western Australia (WA). Methods Epidemiological data and mammographic images were obtained from 628 Aboriginal women and 624 age-, year of screen-, and screening location-matched non-Aboriginal women randomly selected from the BreastScreen Western Australia database. Women were cancer free at the time of their mammogram between 1989 and 2014. MD was measured using the Cumulus software. Kolmogorov-Smirnov tests were used to compare distributions of absolute dense area (DA), precent dense area (PDA), non-dense area (NDA) and total breast area between Aboriginal and non-Aboriginal women. General linear regression was used to estimate the determinants of MD, adjusting for age, NDA, hormone therapy use, family history, measures of socio-economic status and remoteness of residence for Aboriginal and non-Aboriginal women separately. Results Aboriginal women were found to have lower DA and PDA and higher NDA than non-Aboriginal women. Age ( p < 0.001) was negatively associated and several socio-economic indices (p < 0.001) were positively associated with DA and PDA in Aboriginal and non-Aboriginal women. Remoteness of residence was associated with both mammographic measures but for non-Aboriginal women only. Conclusions Aboriginal women have, on average, less MD than non-Aboriginal women but the factors associated with MD are similar for both sample populations. Since reduced MD is associated with improved sensitivity of mammography, this study suggests that mammographic screening is a particularly good test for Australian Indigenous women, a population that suffers from high breast cancer mortality. Electronic supplementary material The online version of this article (10.1186/s13058-019-1113-4) contains supplementary material, which is available to authorized users.

Impact of breast density on cancer detection: observations from digital mammography test sets

“…In Australia, the participation rate of Indigenous women to breast screening is 15% lower than the general populace and the mortality from breast cancer is two-fold higher. 27,28 With breast density in Indigenous Australians described as predominantly adipose 29 and reported to be significantly lower compared with non-Indigenous women 26,30 the current work suggests that Indigenous women would particularly benefit from early breast cancer detection and low false positives provided through engagement with the screening program in the recommended schedule.…”

Post‐mammographic screening behaviour: A survey investigating what women do after being told they have dense breasts

“…shown that Western Australian Aboriginal women have significantly lower breast density (McLean et al 2019) and that the association between breast density and breast cancer risk is even stronger for Aboriginal women (compared to non-Aboriginal women). (Darcey et al 2019) Further investigation of the impact of breast density notification on women from under-studied ethnicities, particularly those where English is not the first language, is needed.…”

Association between Family History of Breast Cancer and Breast Density in Saudi Premenopausal Women Participating in Mammography Screening

“…These studies showed higher odds of dense breast tissue among women with family history of breast cancer in a sister alone. Since ethnic and geographic differences in breast density were documented among different populations [19][20][21], it is increasingly important to investigate the relationship between mammographic density and FHBC in the Saudi population. To our knowledge, no study has explored the relationship between these two determinants of breast cancer risk in a Saudi population.…”