LOS ANGELES — Some women need mammograms more frequently than others, and guidelines should reflect those individual risk profiles, according to authors of a new study on the always-controversial issue of screening for breast cancer.
The standard approach, which is based on age alone, has been challenged in recent years by a number of health experts who contend that some women get more mammograms than they need and others get too few. The new paper, published Monday in the Annals of Internal Medicine, argues for a more complex approach to mammography based on personal risk factors such as age, breast density, family history of breast cancer and even a woman’s personal preference.
Most medical organizations, including the American Cancer Society, recommend healthy women undergo screening every one to two years beginning at age 40 regardless of risk factors. In 2009, the U.S. Preventive Services Task Force recommended a more relaxed schedule: that screening for women ages 40 to 49 should be based on individual risk factors and women ages 50 to 74 should be screened every two years.
Although some cancers would be missed, the task force noted that over-screening carried a high toll on others, through financial costs, exposure to radiation, anxiety and unnecessary medical tests or surgeries resulting from false-positive mammograms. Many doctors expressed dismay at the task force suggestions.
The new study attempts to strike a balance, with more nuanced guidelines — but they will require extra forethought on the part of doctors and their patients, the authors noted.
Previous guidelines “are trying to make one-size-fits-all, while we think of this as a personalized approach,” said Dr. Steven R. Cummings, senior author of the study and senior researcher at the California Pacific Medical Center Research Institute, part of the Sutter Health network.
Such an approach is now possible because of new research showing that dense breast tissue, which has less fat, raises breast-cancer risk while low-density tissue lowers the risk, Cummings said.
“Breast density is the strongest risk factor that we know of, stronger than age and family history,” he said. “We’re able to analyze the relationship between breast density and the risk of getting breast cancer very, very accurately.”
The study was based on a computer model comparing the lifetime costs and health benefits for women who got mammograms every year, every two years, every three to four years or never. The model also weighed individual risk factors and assumed six different outcomes, including remaining healthy, developing some type of breast cancer or death.