Women should get screened for breast cancer every other year starting at age 40, according to draft guidance issued Tuesday by the U.S. Preventive Services Task Force.
That's earlier than the independent panel of experts previously recommended: The last guidance, from 2016, suggested biennial screenings starting at age 50, but noted that women in their 40s could talk to their doctor about getting screened, particularly if they have a family history of breast cancer. Screenings usually involve a mammogram, which is an X-ray image of the breast.
The change is the result of new scientific evidence, the task force said. The rate of breast cancer among women ages 40 to 49 increased 2% per year, on average, from 2015 to 2019, according to the National Cancer Institute.
The task force estimated that the new recommendations could prevent at least one additional breast cancer death for every 1,000 women.
"With our new recommendation, it saves 20% more lives across the board for all women," said Dr. Wanda Nicholson, the task force's vice chair.
She added that the recommendation does not apply to women with a personal history of breast cancer, those who've had an abnormality on a previous biopsy, women exposed to chest radiation at a young age or those with a genetic marker for breast cancer, who may need to be screened more frequently.
But many radiologists think the recommendations don't go far enough.
“They’re taking a step in the right direction, but I do worry about the every-other-year timing," said Dr. Melissa Durand, an associate professor at the Yale School of Medicine Department of Radiology and Biomedical Imaging.
"Annual screening is going to catch the most amount of cancers when they’re at their smallest sizes and when treatment can be most effective," she said. "We will miss cancers if we screen every other year."
Many other medical groups already recommend annual screenings before age 50, including the American Cancer Society and the American College of Radiology, which recommends yearly screenings starting at 40.
In 2019, around 60% of women ages 40 to 49 reported having a mammogram within the past two years, according to the Centers for Disease Control and Prevention.
“We disagree with the U.S. task force in so many different ways,” said Dr. Stamatia Destounis, chair of the American College of Radiology's Breast Imaging Commission.
The group issued guidelines last week recommending that all women have a conversation with their doctor by age 25 to determine if they need to be screened earlier in life. It also recommended that women with dense breasts, a breast cancer diagnosis before age 50 or a personal history of breast cancer get an MRI each year.
Durand said most radiologists follow the American College of Radiology's recommendations. But primary care doctors may look to the task force to know when to refer patients for mammograms, and insurers often follow the panel's recommendations to determine which costs to cover.
Right now, insurance companies cover annual mammograms for women who want them, but some radiologists worry that could change.
Concerns about missed cases among Black women and those with dense breasts
Screening every other year won't do much to decrease disparities in breast cancer outcomes, according to Dr. Phoebe Freer, chief of breast imaging at the University of Utah's Huntsman Cancer Institute.
Black women are 40% more likely than white women to die from breast cancer.
Nicholson said much of that disparity is due to inequities in the health care system, such as a lack of timely follow-up after screenings or uneven access to treatment. But the task force ultimately determined that the risks of annual mammograms — including false positives and unnecessary imaging or biopsies following a scan — outweighed the benefits, she said.
Radiologists also questioned why the task force did not recommend annual screenings for women with dense breasts, which make it harder to detect cancer.
"If you have a mammogram and it shows that you have dense breast tissue, you should get a mammogram every year and you should have some form of supplemental screening, whether it's by ultrasound or MRI," Durand said.
Nicholson said the task force "really looked deep" for evidence that women with dense breasts required separate guidelines but couldn't find it.
Radiologists say annual screenings come with few risks
Although the task force's recommendations weigh the benefits of detecting cancer against the risks of annual scans — including radiation exposure and unnecessary biopsies — radiologists consider those risks to be relatively small.
Durand said the advanced mammogram technology widely used now is unlikely to show a false positive.
And only around 1% to 2% of women who get screened end up needing a biopsy, Freer said.
She added that doctors are likely to detect abnormal growths that aren't cancerous whether women are screened annually or biennially.
Most women, Freer said, "are willing to take the risk of being recalled for additional imaging to then be told that they’re OK."