Women with an average risk of developing breast cancer should receive mammograms every other year starting at age 50, according to a statement from the American College of Physicians (ACP), based on a review of seven sets of existing guidelines.
These recommendations do not apply to people who have previously had breast cancer, those with previous abnormal mammogram results or those with symptoms suggesting breast cancer, according to an ACP press release. They are also not for women at higher-than-average risk, such as those with BRCA gene mutations or a family history of breast cancer.
However, the experts stress that guidelines are just that, and personal decisions about screening should be made by individuals in consultation with their care providers, according to the ACP statement published in Annals of Internal Medicine.
“Beginning at age 40, average-risk women without symptoms should discuss with their physician the benefits, harms and their personal preferences of breast cancer screening with mammography before the age of 50,” said ACP president Ana María López, MD, of the University of Utah Health Sciences Center. “The evidence shows that the best balance of benefits and harms for these women, which represents the great majority of women, is to undergo breast cancer screening with mammography every other year between the ages of 50 and 74.”
Most women with breast cancer are diagnosed after age 50, but some younger women develop aggressive breast cancer that can grow and spread rapidly. This is more likely to occur among Black women, women with inherited BRCA mutations and those with a family history of breast cancer.
Screening guidelines are written by experts who review medical evidence to determine whether benefits outweigh risks or harms at the population level. There is no way to know what the outcome of screening will be for a specific woman—only what is likely to happen for a group of similar women.
Harms of breast cancer screening can include discomfort, radiation exposure, anxiety resulting from false-positive results, the need for more invasive follow-up testing and “overtreatment” of cancer that would not have led to illness or death if left undetected.
Experts and advocates agree that detecting breast cancer at its early stages and starting treatment promptly is the best way to prevent disease progression and improve survival, but there’s less consensus about when to start screening and how often it should be done.
- The latest screening guidelines from the American College of Gynecologists say that women with average breast cancer risk should be offered annual mammograms beginning at age 40 and should start no later than 50.
- The American College of Radiology and the Society of Breast Imaging recommend annual mammograms starting at age 40 for women at average risk, adding that all women should have a risk assessment at age 30, and those at higher risk—including African-American women—should start screening sooner.
- The American Cancer Society says that average-risk women should receive annual mammograms from ages 45 to 55, at which point they can cut back to every other year. Again, women ages 40 to 44 have the option to start screening sooner.
- The United States Preventive Services Task Force recommends mammograms every other year from ages 50 through 74, although the decision about whether to start sooner is an individual one. These guidelines are used to determine which prevention services must be provided free under the Affordable Care Act.
The ACP experts reviewed these and other existing guidelines from the Canadian Task Force on Preventive Health Care, the National Comprehensive Cancer Network and the World Health Organization and came up with four guidance statements:
- Women at average risk and their clinicians should discuss screening between ages 40 and 49, considering the potential benefits and harms as well as personal preferences.
- Average-risk women ages 50 to 74 should receive screening mammograms every other year.
- Average-risk women age 75 or older and those with a life expectancy of 10 years or less should discontinue screening mammograms.
- Clinical breast examination—in which a clinician feels for lumps—should not be used to screen for breast cancer in average-risk women of any age.
The ACP experts noted that for women ages 40 to 49, the harms of annual screening generally outweigh the benefits. For average-risk women over 50, receiving mammograms every other year did not result in a significantly higher likelihood of death compared with annual mammograms, but it did reduce harms. Women screened annually are more likely to have false-positive results, leading to biopsies and surgeries that otherwise would not have been necessary.
“The results of [ACP’s] assessment are four guidance statements that provide clarity and simplicity amidst the chaos of diverging guidelines,” Joann Elmore, MD, MPH, of the David Geffen School of Medicine at UCLA, and Christoph Lee, MD, of the University of Washington School of Medicine, wrote in an accompanying editorial. “These ACP guidance statements represent convergence across differing recommendations while highlighting important points for physicians to consider in shared decision-making conversations with their patients about routine breast cancer screening.”
Click here to read the ACP guidance statement.
Click here to learn more about breast cancer screening.