However, a number of prominent groups say they strongly disagree with the new advice, which was issued by the U.S. Preventive Services Task Force (USPSTF) on Monday.
The USPSTF panel has backed off a 2002 statement advising women to have a routine mammogram every year or two beginning at age 40. The panel now recommends that women undergo mammography screening every two years starting at age 50 and continue being screened through age 74.
The USPSTF concluded that the benefit gained by starting screening at 40 versus 50 is “small” and that the decision to start screening before 50 should be an individual one.
The new guidelines would seem to reopen a debate that raged in the 1990s, but seemed to have been settled years ago. The American Cancer Society (ACS) now recommends that women get an annual mammogram and have a clinical breast examination beginning at age 40.
Otis W. Brawley, MD, the chief medical officer of the ACS, said in a statement that the ACS would stick to its current guidelines.
Mammograms are the “one screening test I recommend unequivocally, and would recommend to any woman 40 and over, be she a patient, a stranger, or a family member,” Dr. Brawley said. The USPSTF is an independent panel, sponsored by the federal Agency for Healthcare Research and Quality, whose members make recommendations about preventive-care services and published the new recommendations in the Annals of Internal Medicine.
The panel’s recommendations are based, in part, on a review of the latest scientific evidence on the benefits and harms of breast cancer screening. The pooled data show that mammography screening does reduce breast cancer death—by 15% for women ages 39 to 49. To prevent one cancer death in this group, 1,904 women would have to be screened. Among women 50 to 59, one death is avoided per 1,339 screenings.
Because breast cancer risk increases with age, younger women are at a somewhat lower risk of developing the disease, explains George W. Sledge Jr., MD, a professor of oncology at Indiana University’s Melvin and Bren Simon Cancer Center, in Indianapolis, and president-elect of the American Society of Clinical Oncology.
They’re also somewhat more likely to have a false-positive mammogram—a test result that triggers a biopsy or other tests, but turns out not to be cancer—because they tend to have denser breasts, he says.
“No one is saying, or no one should say, that screening mammography has no value for younger women,” he says.
What the task force is saying is that the absolute reduction in breast cancer deaths is much greater in an older population.
But the American Cancer Society’s Dr. Brawley reasoned that “the USPSTF is essentially telling women that mammography at age 40 to 49 saves lives; just not enough of them.”