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Nancy Cappello's mammography results returned to normal in 2003. So she was shocked when her doctor found a crest under her right breast six weeks later. She had advanced Stage 3 breast cancer that had spread to her lymph nodes, and her mammogram had missed it.
Cappello later discovered that together with 40 to 50 percent of American women, she is over 40 "dense breasts". This is a classification that can increase the risk of breast cancer (as confirmed by a recent study published in the journal Radiology) and increase the chances that a mammogram will not detect it. Dense breasts have more fibrous or glandular tissue and less fat than other breasts.
To help others and spread the word, Cappello launched a campaign that helped push for a new law in Connecticut in 2009. Mammography shows that her breasts are tight. Some 35 states have passed similar laws, and about six others and the federal government are considering similar laws.
These are generally good news, but such laws can also cause confusion because many women and even many physicians are uncertain as to how to proceed with the information.
"I'm only for women who have information, but there is no evidence to support what to do," says Karla Kerlikowske, family doctor and professor of medicine, epidemiology and biostatistics at the University of California at San Francisco.
Here's what you need to know.
Extra cells, extra tissue
A dense breast alone is already a moderate risk factor for breast cancer. While about half of the women who receive mammograms have dense breasts, only about a quarter of this group has an increased risk of cancer, which is not detected in a mammogram, says Kerlikowske.
Still, there is a risk
The new radiology study, for example, found that out of about 108,000 women aged 50 to 69 who had undergone breast cancer between 2007 and 2015, women with dense breasts 1, Suffering from breast cancer 37 times more frequently than those with non-dense breasts
Those with dense breasts were also nearly three times as likely as women with non-dense breasts to have an aggressive form of cancer. However, the authors of the study found that the absolute risk of these women's breast cancer was still low: only 5 out of 1,000 women with non-dense breasts became ill and 13 out of 1,000 women with dense breasts got cancer.
Dense breasts contain much more cells, connective tissue and collagen than less. tight or greasy, breasts. More cells mean more chances for one of them to get corrupt.
Dense breast tissue can also obscure cancerous lesions on a mammogram, increasing the risk that a cancer will go undetected. The extra tissue has the same whiteness as lesions or tumors on an X-ray, making mammography at dense breasts only 62 to 68 percent effective. This is a big cut of 85 percent effectiveness for women with greasy breasts.
One of the problems with the new laws, says Kerlikowske, is that they do not say the degree of density – only that a woman has thick breasts. The degree of density is important. The closer your breasts are, the higher your risk.
"It's like saying, 'I'll let you know that you're tall,'" says Diana Buist, Scientific Director of the Breast Cancer Surveillance Consortium and Director of Research and Strategic Partnerships at the Kaiser Permanente Washington Health Research Institute in Seattle.
It's a hallmark of your physiology, she explains, but it's not clear how it could increase your chances of getting cancer and what you can do about it. 19659008] What You Should Do
In some states, it is recommended that women with dense breasts perform supplementary imaging such as breast ultrasound or magnetic resonance imaging (MRI). But even then, says Kerlikowske, it is not known if complementary imaging is effective in detecting cancers that are not identified on a mammogram.
Ultrasound and MRI can also be expensive and time consuming, says Kerlikowske imaging tests, which has more chances of getting a false positive or a problem that is not clinically important. This could eventually expose a woman to invasive and unnecessary procedures such as a breast biopsy, not to mention fears and worries.
So, what should you do if you have thick breasts?
First, do not panic. Dense breasts alone are not enough to significantly increase the likelihood of getting cancer, says Kerlikowske. Most importantly, ask if your doctor can determine the level of density and then assess your risk of breast cancer using online tools such as the Breast Cancer Surveillance Consortium Risk Calculator.
If you have dense breasts and other risk factors B. have a family history of breast cancer, in addition to mammography, supplemental imaging such as ultrasound or MRI,
"There is no clear strategy," says Buist. "Be aware of your own risk and understand where you stand on the spectrum."