Mammographic density is one of the strongest predictors of breast cancer risk: Researchers
January 18, 2016
Among the postmenopausal women randomized to EPT, risk of breast cancer risk increased 3.6-fold in 20 percent, with the greatest increase in mammographic density.
The researchers also found that baseline and change in mammographic density were significantly associated with breast cancer risk in the EPT group. Comparing breast density from the first and second mammogram, they could "predict" the women at increased risk of developing breast cancer.
Consistent with the original findings of the WHI, the researchers reported an association between EPT and breast cancer risk; there was a 24 percent increased risk, which was explained by the change in breast density, according to Byrne.
In addition to considering change in breast density among postmenopausal women taking EPT, "baseline breast density needs to be incorporated more in thinking about breast cancer risk," said Byrne. "We need to better understand patients who aren't on estrogen and progestin therapy and what makes some women's breast density decline and others stay high."
3768. Comparison of breast density measured by dual energy X-ray absorptiometry with mammographic density among adult women Embargo: 9:00 a.m. ET, April 20, 2010
Measuring breast density by dual energy X-ray absorptiometry (DXA) may provide a low-radiation option to evaluate breast density for women who do not undergo mammography.
According to lead researcher Gertraud Maskarinec, M.D., Ph.D., it is important to study breast cancer risk in younger women and identify women for targeted prevention strategies early in life. However, evaluating breast cancer risk through use of mammography is known to have a level of radiation exposure that is not acceptable for younger women; therefore, other methods are needed to evaluate breast density.
"Our findings indicate there is agreement between breast density as determined by mammograms and the use of DXA," said Maskarinec, who is professor of epidemiology at the Cancer Research Center at the University of Hawaii, Honolulu.
DXA is widely used to evaluate bone density and total body composition. It is commonly available in medical care settings and is known to have low radiation exposure.
Maskarinec and colleagues conducted a cross-sectional study to compare breast density measured by DXA with mammographic density among 101 women aged 30 years and older with a normal mammogram. Participants completed questionnaires on demographic, reproductive and medical information, and then received DXA scans of both breasts.
Both DXA and mammographic measures showed high correlations between left and right breasts and common risk factors showed similar patterns for both measurements.
"We now know something about how DXA performs when used to measure breast density," said Maskarinec. "This is not practice-changing at the moment, but it does present the potential for future studies to elaborate on DXA's use as a new research tool in breast cancer prevention studies among adolescents and young women."
Source: American Association for Cancer Research