Women at average risk for breast cancer should get screening mammograms every other year starting at age 40, according to a proposed guideline update from the U.S. Preventive Services Task Force (USPSTF), reflecting improved diagnostic technology and treatment.
The update reverses a controversial recommendation made by the panel in 2009, when it advised against routine mammograms for women in their 40s and said biennial screening should start at age 50, unless women and their doctors decided earlier screening was appropriate.
At that time, the net benefit of mammography screening for women in their 40s, minus the potential harms, was small, said Dr. Carol Mangione, the immediate past chair of the USPSTF.
“A lot of things have changed since then”, she said.
Breast cancer rates in younger women have been rising, digital mammography advances have improved their accuracy, and better treatments are resulting in improved survival, she said.
As a result, new computer models suggest that if biennial screening started at age 40 instead of age 50, and if everyone who is eligible got a mammogram, breast cancer mortality in the United States would be reduced by 20%, said Mangione, who chairs the department of medicine at the David Geffen School of Medicine at the University of California.
The benefit would be even greater for Black women, who generally have more aggressive breast cancers and poorer survival, the panel said.
The Task Force recommendation applies to cisgender women and people assigned female at birth who are at average risk of breast cancer, including those with a family history of breast cancer and certain other risk factors, such as having dense breasts.
The recommendation does not apply to people with a personal history of breast cancer, a very high risk due to certain genetic predisposition or a history of high-dose radiation therapy to their chest at a young age, or a lesion on previous biopsies. These people should consult their healthcare professional for individualized guidance about screening.
The new recommendation does not change what is covered by insurance, because insurance companies in the U.S. are legally required to fully cover mammograms every year for women over age 40 who want them, the panel said.
The USPSTF also said there is not enough evidence to assess the balance of benefits and harms of mammography in women over age 75 or of using ultrasonography or magnetic resonance imaging in women with dense breasts who have normal mammography results.
The potential harms of screening include false-positive results that lead to unnecessary biopsies and sometimes to mistaken diagnoses of breast cancer, research has shown.
The panel’s 2009 recommendation that women in their 40s decide for themselves whether to get mammograms was controversial.
The American Cancer Society (ACS) applauds the return in USPSTF recommendations to begin screening at age 40, Chief Scientific Officer Dr. William Dahut said in a statement.
However, he added, the ACS recommends annual mammograms because “current evidence indicates that biennial screening in (women under age 55) is associated with a diagnosis of more advanced disease”.
American College of Obstetricians and Gynecologists spokesperson Dr. Christopher M. Zahn said in a statement, “ACOG has long asserted that regular screening via mammography starting at 40 years reduces breast cancer mortality in those without additional risk factors”.
“Recognizing that Black women are more likely to die of breast cancer than white women, (the earlier start to screening) could help make a meaningful difference in ensuring that more Black women are diagnosed earlier”, Zahn added.
The draft recommendation will be available for public comment until June 5, 2023.