Women should start getting screening mammograms at the age of 40, rather than 50, according to new draft recommendations from an influential national health panel, which found that starting breast cancer screening 10 years earlier could save thousands of lives per year.
The new advice is a change from current guidelines, which formally advise starting biennial screening by age 50 but suggest women in their 40s discuss the benefits and risks of mammography with their doctors and come to an individual decision.
Recent evidence shows more women in their 40s are getting breast cancer, with the number of newly diagnosed women increasing about 2 percent each year, said John Wong, an internist and professor of medicine at Tufts University School of Medicine, who is on the task force. The panel now estimates that by starting screening earlier, doctors can detect breast cancers earlier, saving more lives.
“It is now clear that screening every other year starting at age 40 has the potential to save about 20 percent more lives among all women, and there is even greater potential benefit for Black women, who are much more likely to die from breast cancer,” Wong said.
Breast cancer is the most common cancer among women in the United States, aside from skin cancers, and the second-leading cause of cancer-related death in women. Black women are at a higher risk than White women of developing breast cancer before age 40 and are more likely to develop a more aggressive form called triple-negative breast cancer, according to data from the American Cancer Society.
More than 43,000 women die of breast cancer each year in the United States, the data shows.
A mammogram, which is considered the gold standard for breast cancer screening, is an X-ray of the breasts that is used both to screen for signs of breast cancer and help diagnose palpable lumps found on exam.
Annual vs. biennial screening
The task force said it made its recommendations after analyzing the potentially lifesaving benefits of early breast cancer detection vs. potential harms, including false positives that may take a psychological toll and lead to unnecessary follow-up tests and procedures, as well as the added — yet minimal — radiation exposure.
Many breast cancer experts applauded the task force for lowering the recommended age that women should start screening mammography. Still, some professional organizations and physicians who focus on breast health say the recommendations don’t go far enough, and, among other things, are urging the task force to advise annual mammograms to screen for cancer.
Critics say that for women, an annual appointment for a mammogram is easier to remember than an every-other-year appointment. More importantly, they note that skipping a year between screenings would give undetected cancers more time to grow.
“A two-year interval can allow a more aggressive breast cancer to grow significantly and reduce the chance of the patient being cured or increase the chance that she needs additional treatment,” said Maxine Jochelson, chief of the breast imaging service at Memorial Sloan Kettering Cancer Center.
But limiting screening to every other year can also reduce risk for false positives. About 12 percent of screening mammograms result in callbacks, in which a woman is asked to return for additional testing because of an abnormality on the scan. Only 4.4 percent of those calls, or 0.5 percent overall, conclude with a cancer diagnosis, according to a study of nearly 3 million screening exams.
Jochelson said that while callbacks are stressful for women, that shouldn’t be a reason to recommend against annual screening.
“The risk of getting called back is something they have been talking about for a long time,” she said. “Yes, women are anxious when they are called back for screening mammograms. And I certainly appreciate the anxiety. But then most of them have a normal exam, and life goes on.”
Different screening recommendations
Most doctors and insurance companies follow the recommendations of the task force, which is an independent board of doctors and other experts appointed by the Department of Health and Human Services to evaluate care aimed at prevention or early detection.
But a number of other organizations have made different recommendations about mammography screening, and the wide variation in advice has been confusing for women and their doctors.
The American Cancer Society recommends that all women should start annual screening by the age of 45, and that certain women at higher risk should begin annual screenings by age 40.
The American College of Radiology and Society of Breast Imaging state that women at average risk should start annual mammograms at 40, but by 25, all women should talk to their doctors about their individual risk factors to determine whether earlier screening may be needed for them.
The American College of Obstetricians and Gynecologists calls for mammograms every one to two years beginning at 40 for patients at average risk of breast cancer. As with when to start, there is no agreed-upon guidance on when women should stop screening.
William Dahut, chief scientific officer of the American Cancer Society, said these opposing views can be a problem.
“I think it’s hard enough for physicians to keep track, much less to have patients have a sense of what they should be doing,” he said. “Simplifying guidelines — making them as cohesive across different organizations — is a goal we all should work for.”
A need for more research on dense breasts
The task force noted in its draft that there was not enough evidence to assess the risks vs. the benefits of screening mammography in women older than 74.
The recommendations apply to women with a family history of breast cancer and those who have dense breasts — a known risk factor for breast cancer, which can be more difficult to detect with dense breast tissue.
They do not apply, however, to women who have had breast biopsies, breast cancer or are considered high risk, such as those with BRCA1 or BRCA2 genetic mutations. Wong said the recommendations are based on preventive medicine, and women who are at high risk should be under the care of breast cancer specialists who will probably have more tailored guidance for them.
The new recommendations do not provide specific guidance on the use of alternative or additional forms of imaging, such as ultrasound or magnetic resonance imaging (MRI), which may be needed when patients have dense breasts or do not have enough breast tissue for a mammogram.
This includes women who have had all their breast tissue removed through a mastectomy, as well as nonbinary or transgender people who have had most — but not all — of their breast tissue removed and still need routine screening, experts said.
In March, the Food and Drug Administration updated its mammography regulations to require facilities to tell patients about the density of their breasts and suggests that those with dense breasts speak to their doctor about their individual risk.
The task force stated in its draft that current evidence is “insufficient to assess the balance of benefits and harms of supplemental screening for breast cancer” in women with dense breasts.
“I’m sure it’s unsettling to be told you’re at increased risk for breast cancer, and yet we don’t have the evidence to say whether or not additional screening with ultrasound, MRI or anything else could be helpful, or even potentially harmful. We are calling urgently for more research because these women deserve to know,” Wong said.
Professional organizations, physicians and individuals can visit the task force’s website to weigh in on the proposed draft until June 5. Once the recommendations have been finalized, they will be published in JAMA, the American Medical Association’s journal.