Women Over 70 at Risk for Overdiagnosis of Breast Cancer: Study

Older women are at risk of breast cancer overdiagnosis, leading some doctors to raise questions about the necessity of continued screening in a new study.

Researchers from the Yale School of Medicine tracked over 54,000 women ages 70 and older who received a mammogram, the standard test used to screen for breast cancer, in 2002. They continued to monitor the participants and incidences of death among them from breast cancer for up to 15 years.

For those between the ages of 70 to 74, researchers found that up to 31% of breast cancer among the screened participants was overdiagnosed,and the potential for overdiagnosis just increased with age. 

For women ages 75 to 84, potentially 47% of cases were overdiagnosed. And for those over the age of 85, up to 54% of cases were overdiagnosed.

"It's critical for older women who are thinking, 'Should I continue screening,' to understand what is the full range of risks and benefits," Ilana Richman, M.D., MHS, an internal medicine physician at Yale Medical School who led the research, told Reuters. "I'm interested in what can we do to help women understand their options."

Overdiagnosis is defined as a doctor finding a cancer or other issue that might have gone away on its own, or might not have caused any issues within the patient’s lifetime, according to the Centers for Disease Control and Prevention (CDC). 

An overdiagnosis can lead to overtreatment, such as surgery or radiation therapy, both of which can have detrimental impacts on a person’s quality of life, financial situation and emotional health.

Notably, the study did not find a significant reduction in the number of breast cancer deaths related to the screenings. 

This is not the first time doctors have raised questions associated with overdiagnosis and breast cancer specifically. Mammography, which is an X-ray of the breast, has been used for over 50 years to screen for breast cancer, and for the past decade, numerous pieces of research and editorials have continued to draw attention to the risk for overdiagnosis. 

One review from the Oregon Health and Science University in 2016 noted “false-positive results are common and are higher for annual screening, younger women, and women with dense breasts.”

Authors from an Australian review in 2017 wrote: “Each time a woman has a screening mammogram, she has roughly around a 3% to 12% chance of being recalled for further assessment, hence repeated regular screening confers a cumulative risk of experiencing a false-positive screen.”

In other words, continuous screening might eventually lead to a person getting called back for further testing or biopsy. Researchers in that review went on to write that the anxiety often associated with additional testing might be relatively short-lived, but that there could be “considerable financial” costs that came with the testing as well.

Currently, the U.S. Preventive Services Task Force recommends women ages 50 to 74 who are at average risk get screened every two years. Women ages 40 to 49 should discuss with their doctors whether screening is right for them, based on their personal histories. 

In 2020, the latest year for which data is available, over 239,000 women were diagnosed with breast cancer and over 42,000 women died of the disease, according to the CDC. Breast cancer is the second most common type of cancer for women in the U.S.