There's a new set of final recommendations on when women should get mammograms, and it might add to confusion, but there's one basic bottom line: It's unlikely to change much for women.
The U.S. Preventive Services Task Force (USPSTF) has made final its controversial advice on breast cancer screening and it's much the same as the draft released last year. The panel says women in their 40s can get mammograms every year if they want to, but said it really needs to be up to a woman to decide if she wants to risk the anxiety of getting a false positive result — one showing a breast lump that turns out not to be cancer, after all.
It says women over 50 should get a mammogram every other year and it's not clear if women over 75 should bother with mammograms.
"Our findings support a range of choices available to women—from beginning regular mammograms in their 40s, to waiting until age 50 to begin screening, when the likelihood of benefit is greater," says the Task Force's vice chair, Dr. Kirsten Bibbins-Domingo, an internal medicine specialist at the University of California, San Francisco.
"We found that the balance of benefits and harms are probably the best and most effective for women between the ages of 50 to 74," Dr. Albert Siu of Mount Sinai School of Medicine, who chaired the panel, told NBC News.
This is all advice for women at average risk of breast cancer. Women who know they have genetic mutations that raise the risk, who have a family history of breast cancer or other risk factors need to consider mammograms earlier and more often. The National Cancer Institute has an online risk calculator here.
Usually, what the USPSTF says affects insurance coverage of medical services, but not in this case. Congress regularly passes measures requiring health insurance companies to pay for mammograms for women who want them starting at age 40.
Nonetheless, the announcement, published in the Annals of Internal Medicine, prompted denunciations from experts who disagree, including the American College of Obstetricians and Gynecologists (ACOG).
"We disagree," the group tweeted.
"ACOG strongly supports shared decision-making between doctor and patient, and in the case of screening for breast cancer, it is essential," said Dr. Mark DeFrancesco, the group's president.
"Given the differences among current organizational recommendations on breast cancer screening, we recognize that there may be confusion among women about when they should begin screening for breast cancer."
Last year the American Cancer Society revised its guidelines, saying most women can start at age 45. ACOG says it plans a "consensus conference" later this month to try to give better advice to women.
Breast cancer is a leading killer of U.S. women. Every year, it's diagnosed in 200,000 women and a few men, and kills around 40,000.
There's also some disagreement about how many lives mammograms can save. Some studies indicate that, across large populations, women who got annual mammograms starting in their 40s weren't any less likely to eventually die of breast cancer than women screened later or less often.
"Still, the bottom line is that mammography saves lives. When to start screening and how often to undergo mammography is a personal decision. No model can provide those answers," said Dr. Jeanne Mandelblatt, of Georgetown Lombardi Comprehensive Cancer Center, who helped lead a study that helped inform the USPSTF's decision.
They tried to calculate just how many lives mammograms do save.
Among women who never get one, about 13 percent will be diagnosed with breast cancer after age 40, they found. About 2.5 percent of unscreened women will die of breast cancer.
When women aged 50 to 74 are screened every two years, that risk of dying drops by just over 25 percent. It prevents about seven deaths out of every 1,000 women screened.
Dropping the screening age to 40 averts one more death per 1,000 women, Mandelblatt's team found.
If women over 50 got a mammogram every year, that would avert two more deaths per 1,000, or 9 in 1,000. But it would also generate far more "false positives" and two women out of every 1,000 would be needlessly treated for cancer, they calculated.