The age of cutoff is similar worldwide. In Australia, women are invited for routine screening between the ages of 50 and 74, while in the UK, they are invited between 50 and 70 years.
But now, a new study suggests that there is no reason for older women to skip mammograms and that such screening decisions should be based on a woman's personal health.
"This is the largest study on this topic," said Dr. Cindy Lee, an assistant professor at the University of California, San Francisco School of Medicine and lead author of the study. She is scheduled to present the study at the annual meeting of the Radiological Society of North America
"It's surprising that there's so much uncertainty and so much controversy about when we should continue and when we should stop the breast cancer screening, and this study tries to answer that question," she said. "Our study supports that there shouldn't be a specific age cutoff. In other words, there's no magical age number that you should stop people from getting screened for breast cancer, because it's a really individual decision."
Most health insurance programs in the US cover screening mammograms
, which are X-ray photos of the breast, and getting mammograms every two years
can lower a woman's risk of dying from breast cancer, according to the Centers for Disease Control and Prevention
A cancer detection trend discovered
The new study used data from about 6 million screening mammograms performed across the country between 2008 and 2014. That data, which included about three million women aged 40 to 90 years old, came from the American College of Radiology's National Mammography Database
Lee and her colleagues analyzed the data, taking a close look at patients' ages, their screening results, how many were called back for additional evaluation and their biopsy results.
They then found that as the age of patients increased until 90 years old, so did the rate in which cancer was detected in their screenings.
In other words, "as women get older, you're finding more cancers per 1,000 screening mammograms," Lee said. "It makes sense to us that the cancer detection rate is significantly higher with increased age, because breast cancer is a disease of older women."
Previous research has shown that many cancers detected by mammograms represent over-diagnosis
Yet the new study shows that mammograms still can be effective and might even improve in performance as women age, said Dr. Andrew Kaunitz, professor and associate chairman of the University of Florida's Department of Obstetrics and Gynecology, who was not involved in the study.
'The decision when to stop has to be individualized'
While the new study demonstrates that screening can be effective at finding disease among older women, it does not show that this early detection prevents breast cancer deaths, said Dr. Otis Brawley, chief medical officer of the American Cancer Society and a practicing oncologist, who was also not involved in the study.
"I do believe that early detection in this age group can prevent deaths, but this paper does not address that," Brawley said. More research is needed to provide evidence that supports that conclusion.
The new study, however, still offers information that has not been provided before in previous research, Brawley said.
"Some organizations, such as the ACS, have recommended that screening continue until the woman has a life expectancy of less than 10 years," Brawley said. "For the average American woman, life expectancy is 82, that translates into stopping screening at 72. ... The decision when to stop has to be individualized to a woman's health history. There are some 80-year-olds in very good health. Indeed the life expectancy of a healthy 75-year-old woman is 13 years and a healthy 80-year-old is 89."
Kaunitz, who is not associated with the cancer society, added, "In my practice, many of the women in their mid-70s and older I see are active and have life expectancies that exceed one decade. The majority of these patients wish to continue screening mammograms, a decision I support."