The Food and Drug Administration released new standards Thursday that could potentially help more women detect breast cancer earlier.
The new rules will require mammogram providers nationwide to notify women if they have dense breast tissue and recommend that they consult with a doctor about whether they need additional screening.
“Today’s action represents the agency’s broader commitment to support innovation to prevent, detect and treat cancer,” Dr. Hilary Marston, the FDA’s chief medical officer, said in a statement.
Dr. Anne Hoyt, the co-medical director for breast imaging at UCLA, called it "a step in the right direction."
"Sometimes women that have breast cancers that are present, those breast cancers are not seen on the mammogram because they are hidden by breast density," she said.
The FDA's move is important because the risk of breast cancer is of real concern to many patients, said Dr. Harold Burstein, a medical oncologist at the Dana-Farber Cancer Institute in Boston and a professor at Harvard Medical School.
"The identification of dense breast tissue can be a marker of slightly greater risk of getting breast cancer, and it may need additional breast imaging," said Burstein, who likened the challenge of reading mammograms to “looking through frosted glass.”
Mammogram providers will be required to implement the new standards within 18 months, according to the agency.
More than 297,700 women will be diagnosed with invasive breast cancer this year, and about 43,700 will die from the disease, according to estimates from the American Cancer Society.
Women with dense breasts have a higher chance of getting breast cancer, according to the Centers for Disease Control and Prevention. The denser your breasts are, the higher your risk.
The condition is very common: About half of women 40 and older have dense breasts, based on CDC statistics. Dense breasts have more tissue and fat, so reading their mammograms is more challenging and cancers can get missed.
How do you know you have dense breasts?
JoAnn Pushkin, executive director of New York-based DenseBreast-info, a website that educates the public about dense breasts, said women can't detect the condition on their own because it has "nothing to do with the way your breasts look or feel."
“It is the tissue composition of the breast,” she said.
The only way to tell whether you have dense breasts is via a mammogram, which doctors generally recommend every one or two years for women starting in their 40s or 50s. Women with dense breasts are recommended to also get an ultrasound.
Mammograms aren't a perfect solution either, Pushkin said, because dense breasts and cancer can look similar on X-ray images.
"Dense breasts show up white on a mammogram. Unfortunately, so does cancer," she said. "So that cancer in dense breast tissue is like trying to find a snowball in a blizzard easily missed and overlooked."
Awareness of risks associated with dense breasts
In 2019, the FDA first proposed new rules for breast cancer screenings that would require health care providers to give women more information about the risks associated with dense breasts. In October, the agency said it was optimistic that the final rule would be published by early 2023.
Thirty-eight states already require providers to give women information about breast density after a mammogram, but not all of them require providers to notify a woman if she herself has dense breasts.
The FDA's new rules released Thursday essentially set a minimum amount of information mammogram providers will be required to tell women.
It "provides uniform guidance," Burstein said, because "it extends across the country."
It is hoped the FDA’s decision will increase awareness of the condition and encourage even more women to get mammograms to find out whether they are at risk, he said.
“Just because you have dense breast tissue doesn’t mean you have breast cancer, and it doesn’t mean you’re going to get breast cancer,” he said. “But what it might mean is that you need some extra imaging.”
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