Breast cancer is one of the leading causes of death in the U.S. today.
The New York Times reports on dense tissue mammograms. A new study shows that having dense breast tissue does not necessarily mean that you have a higher chance of getting breast cancer.
For some time now experts have believed that not only is breast density linked to a higher risk of cancer but it also makes it harder to detect. Dense tissue often hides cancer from x-rays.
Despite what was previously believed, experts from a new study are now saying that women with dense breast tissue are not necessarily at a higher risk. Many patient advocates have been pushing for women with dense breasts to ask doctors about extra tests such as ultrasounds or an MRI to check for tumors. These tests can help find tumors when mammograms cannot.
Dr. Constance Lehman, is the author of the study and the director of breast imaging at the University of Washington in Seattle.
“While mammography is currently the best screening tool we have, there are women for whom mammography is not enough. We hope this work can help women be better informed regarding whether or not supplemental screening, such as with ultrasound” according to Dr. Lehman.
This new study was published on Monday in Annals of Internal Medicine. The study shows that only around fifty percent of women with dense tissue are at such a high risk that they need extra tests.
The Times reports, “Instead of looking at density alone, women and their doctors should also consider other risk factors when making decisions about additional screening, the researchers concluded.”
The study was led by a big team of experts in breast cancer and epidemiology, was partly done because many physicians thought that the laws and advocacy groups had gotten ahead of the science. Around 45 percent of all women have dense breasts, but not every woman with that finding has a greater threat of developing cancer.
Why are dense breasts considered concerning?
Scientists say that dense breasts have a relatively high proportion of glandular or connective tissue, which shows up as white on mammograms. Tumors also look white, so dense tissue can hide them. Breasts that are not dense have more fat, which looks dark on mammograms, so tumors stand out more.
How can density be found?
It can be detected only by mammograms and is reported in one of four categories, from almost entirely fatty to extremely dense.
What were the results of the study?
The findings are based on the medical records of 365,426 women who were between the ages of 40 to 74 who had screening mammograms from 2002 to 2011.
“The researchers wanted to know if they could detect whether, among all the women with dense breasts, any distinct subgroups had a higher risk than others of developing an interval cancer, meaning one that is found less than a year after a normal mammogram,” according to The Times.
The study used an online calculator that predicts a woman’s chance of getting breast cancer. The calculator asks five questions about their age, race, breast cancer family history etc.
The study’s results showed that women with certain combinations of breast density and five-year risk levels had the greatest odds of an interval cancer. “Two groups had high rates of interval cancer, defined as more than one case per 1,000 mammograms,” according to The Times.
Women with dense breasts had around a 1.5-2% higher risk of getting cancer.