False-positive mammograms discourage some women from future screenings

Early detection of breast cancer through mammography screening continues to save lives. However, abnormal findings on mammograms can lead to women being recalled for additional imaging and biopsies, many of which turn out to be “false positives,” meaning they do not result in a cancer diagnosis. False positive results can also have financial consequences for patients and cause significant emotional distress.

A large new study led by the UC Davis Comprehensive Cancer Center found that women who received a false-positive result that required additional imaging or biopsy were less likely to return for that follow-up screening.

The research has been published in the Annals of Internal Medicine on September 3. It analyzed data from more than 3.5 million screening mammograms performed nationwide between 2005 and 2017 on more than 1 million patients aged 40 to 73.

“The finding raises concerns about the potential unintended consequences of false-positive results, where women may avoid screening mammograms in the future,” said lead author Diana Miglioretti, cancer center investigator and chief of the Department of Biostatistics at UC Davis.

The findings are worrying for researchers

The study found that 77% of women with a negative mammography result returned for subsequent screening. But this rate dropped to 61% after a false-positive finding that required another mammogram within six months to confirm the results, and to 67% if a biopsy was recommended.

The impact was even greater among women who received false-positive results on two consecutive mammograms, where follow-up at short intervals was recommended: only 56% returned their next screening mammogram.

The high percentage of women who do not return for future screening is concerning to the research team.

“It is important for women with false-positive results to continue screening every one to two years,” Miglioretti said. “Having a false-positive result, especially if it results in a diagnosis of benign breast disease, is associated with an increased risk.” to be diagnosed with breast cancer in the future.”

The study also found that Asian and Hispanic/Latinx women were the least likely to return for future screening mammograms after a false-positive result, which may contribute to existing health disparities.

False-positive results are common, especially among younger women. They occur in 10–12% of mammograms in women aged 40–49 years. After ten years of annual screenings, 50-60% of women can expect at least one false positive and 7-12% at least one false positive with a recommendation for a biopsy.

“It is important to understand that most women who are recalled for additional imaging because of a finding on a screening mammogram do not have breast cancer,” Miglioretti said. “They should try not to worry if they are recalled for additional testing. It is a normal and usual part of the screening process.”

It is important for women to understand that approximately 10% of the time additional imaging is needed to better view a finding on a screening mammogram.

Steps to consider

Miglioretti said women who feel anxious while waiting for their screening mammogram results should consider requesting an interpretation of their mammogram on the spot. Some facilities offer this service, along with same-day diagnostic testing, if there is a suspicious finding.

She said it is also important that doctors carefully explain false-positive results to their patients to reassure them that the result was negative and emphasize the importance of continued screening.