New draft guidance drops breast cancer screening age from 50 to 40 for women with average risk

Most women with average risk should start screening for breast cancer at age 40, and they should get screened every other year through age 74, according to new draft guidance Tuesday from the U.S. Preventive Services Task Force, a federally appointed group whose decisions guide insurance policies.

Prior task force recommendations said women should start screening at age 50 but said women in their 40s can consider screening at younger ages based on conversations with their doctor about the benefits and risks of screening based on their individual health and personal preference.

The new guidance comes on the heels of mounting evidence showing higher rates of breast cancer among women in their 40s, including a sharp 2% annual increase from 2015 to 2019.

"Whenever you have more people in a given decade getting a condition, then the value of screening at a younger age goes up," said Dr. Carol Mangione, immediate past chair of the U.S. Preventive Services Task Force.

"The goal is to find cancer earlier, when it's treatable and curable," said Dr. Maxine Jochelson, chief of the breast imaging service at Memorial Sloan Kettering. "I do think that by screening women earlier and more frequently, we will find smaller cancers more frequently."

Breast cancer outcomes are not felt evenly across society, with Black women more likely to get aggressive cancers at a younger age and 40% more likely to die of breast cancer than white women, according to a recent study.

The new guidance seeks to drop the screening age for women of all races to help ease this disparity -- although Mangione cautioned that screening alone won't be enough to eliminate inequities.

The new draft recommendation applies to cisgender women and all other people assigned female at birth who are at average risk of breast cancer. It does not apply to people who have a significantly higher-than-average risk of breast cancer, including breast cancer survivors and those who are predisposed because of their genetics or personal medical history.

Medical experts say there are risks to screening too early or too often, including the risk of false positives.

Still, the updated task force guidance may bring it more in line with guidance from other major medical groups, which already recommend that women start getting screened at a younger age.

The American Cancer Society, for example, says mammogram screening is optional for those ages 40-44. They say women ages 45-54 should get mammograms every year and after that, women can choose to drop down to every other year if they wish.

"We're very happy that the [task force's] age to begin screening for mammography has been lowered to 40. We do think that's wonderful news," said Dr. William Dahut, chief scientific officer at the American Cancer Society.

Dahut said women should "be aware that these guidelines, again, are just guidelines for average risk," and it's important for women to understand their own individual risk and "not be afraid to advocate for screening when it's appropriate for them."

Mangione agreed that any woman with symptoms, including a lump or change in the nipple, should get screened immediately, even if she is younger than 40.

"It's really important that primary care doctors understand [these] recommendations are for average-risk women without symptoms," Mangione said.

The task force said more research is urgently needed about the benefits of additional screening for women with dense breasts.

About half of women have dense breast tissue, which increases cancer risk and means mammograms may not work as well for them.

The task force stopped short of a recommendation, but other experts interviewed by ABC News said they recommend additional imaging for their patients with dense breasts, which can include ultrasound or MRI.

The task force also said more research is needed about the benefits and harms of screening in women 75 and older. Currently, there isn't enough evidence for the task force to recommend for or against screening after 74.

The task force will hear comments until June 6 and finalize its guidance after.

"Science is not stagnant," Mangione said. "It would be irresponsible if we saw evidence that we could save lives and we didn't change the recommendation."

Editor's note: This article has been updated to clarify previous screening recommendations.