False-positive results linked to lower likelihood of further cancer screenings

Key takeaways:

• False-positive mammography results decreased the likelihood of participation in subsequent screenings.
• Improving provider-patient discussions on harms and benefits of screening could help, experts said.

False-positive mammography results discouraged women to return for further screenings, results from an observational cohort study published in the Annals of Internal Medicine showed.

This trend appeared more pronounced among women who received recommendations to expedite their follow-up mammogram or undergo biopsy, researchers observed.

According to Diana L. Miglioretti, PhD, a professor at the University of California Davis School of Medicine, and colleagues, prior studies examining ties between false-positive mammography results and subsequent screenings have shown contradictory results.

They added that the U.S. Preventive Services Task Force recently underlined the need for research “to better understand the potential harms associated with screening and identified a critical evidence gap regarding whether the balance of benefits and harms of breast cancer screening varies across racial and ethnic groups.”

In the current study, the researchers assessed screening mammograms among 1,053,672 women aged 40 to 73 years without a breast cancer diagnosis.

The analysis included mammograms performed between 2005 and 2017 at 177 breast imaging facilities participating in the Breast Cancer Surveillance Consortium registries.

Miglioretti and colleagues determined the likelihood of a patient returning for subsequent screening based on whether they had a true-negative or a false-positive exam where they were recommended for immediate additional imaging only, short-interval follow-up or biopsy.

Of the 3,529,825 mammograms, 184,482 were true negatives and 345,343 were false positives.

The researchers found that 76.9% (95% CI, 75.1%-78.6%) of women with a true negative result returned for subsequent screening. This percentage decreased by:

• –1.9 percentage points (95% CI, –3.1 to –0.7 percentage points) following a false-positive recall for additional imaging only;
• –10 percentage points (95% CI, –14.2 to –5.9 percentage points) following a false-positive biopsy recommendation; and
• –15.9 percentage points (95% CI, –19.7 to –12 percentage points) following a false-positive short-interval follow-up recommendation.

Additionally, Asian and Hispanic/Latinx women had the largest decreases in the likelihood of returning after a false-positive exam with a recommendation for short-interval follow-up (–20 to –25 percentage points) or biopsy (–13 to –14 percentage points).

Miglioretti and colleagues did not explore reasons why women discontinued screening, but they said one could be that the experience “was negative enough” to continue participating in screenings.

“Offering same-day interpretation and diagnostic work-up of screening mammography may decrease the anxiety and inconvenience associated with having to return for a second visit,” they wrote.

In an accompanying editorial, Neha Pathak, MBBS, MD, DM, from the University of Toronto in Canada, and colleagues pointed out that the USPSTF issued new guidance since the study, recommending starting breast cancer screening at the age of 40 years.

They added that just 29% of all women in the study were aged 40 to 49 years.

“Given that screening from age 40 to 49 was not guideline-recommended at the time this study took place, the choice of using age 40 to 49 years as the “reference group” could influence the observation,” they wrote.

Pathak and colleagues pointed out that solutions to this issue will be “multifactorial,” like improving patient-provider discussions before screening and during follow-ups.

“Clear health care information on the benefits and harms of breast cancer screening, including false-positive results and their implications, should be provided to all women; this is likely to lead to better, individualized decisions regarding their own health,” they wrote.

References:

• Miglioretti D, et al. Ann Intern Med. 2024;doi:10.7326/M24-0123.
• Pathak N, et al. Ann Intern Med. 2024;doi:10.7326/M24-0893.