Insufficient Awareness of Breast Density and Its Impact on Breast Cancer Detection and Risk
In a study reported in the Journal of Clinical Oncology, Rhodes et al found that only about half of screening-age women had awareness of breast density and adequate knowledge of its impact on breast cancer detection and risk.
Breast density is an important factor contributing to false-negative mammography screening and the primary factor in poorer performance of screening in younger women. Increased breast density is associated with a threefold increase in recall rate and false-positive screening results. It is a strong independent predictor of breast cancer risk. Legislation mandating disclosure of breast density information currently has passed in 21 states.
The study involved a national cross-sectional survey in English and Spanish using a probability-based sample of screening-age women. Connecticut, the only state with breast density legislation in effect for > 1 year before the survey, was oversampled.
Levels of Awareness and Knowledge
Of 2,311 women surveyed, 65% responded. Overall, 58% of women had heard of breast density, 49% knew that it affects breast cancer detection, and 53% knew that it affects breast cancer risk. In multivariate analysis, increased breast density awareness was associated with white race (odds ratio [OR] = 0.57, P = .03, for black women; OR = 0.23, P < .001, for Hispanic women), household income (OR = 1.07 per category increase, P < .001), education (OR = 1.19 per category increase, P < .001), diagnostic evaluation after a mammogram (OR = 2.64, P < .001), and postmenopausal hormone therapy use (OR = 1.69, P = .002).
Knowledge regarding the masking effect of breast density in screening was associated with higher household income (OR = 1.10, P < .001), higher education level (OR = 1.22, P = .01), prior breast biopsy (OR = 2.16, P < .001), and residing in Connecticut (OR = 3.82, P = .003, vs other states). Connecticut residents were also more likely to have discussed breast density with a health-care provider (67% vs 43%, P < .001).
Study Conclusions
The investigators concluded: “Disparities in [breast density] awareness and knowledge exist by race/ethnicity, education, and income. [Breast density] legislation seems to be effective in increasing knowledge of [breast density] impact on breast cancer detection. These findings support continued and targeted efforts to improve [breast density] awareness and knowledge among women eligible for screening mammography.”
Deborah J. Rhodes, MD, of the Mayo Clinic, is the corresponding author for the Journal of Clinical Oncology article.
The study was supported by the Mayo Clinic Center for Individualized Medicine. The study authors reported no potential conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
