USPSTF Suggests Lowering Breast Cancer Screening Age in Draft Recommendation

May 11, 2023

Article

The US Preventive Services Task Force is working on a draft recommendation which would lower the age of breast cancer screenings from 50 years to 40 years for women at average risk.

USPSTF Suggests Lowering Breast Cancer Screening Age in Draft Recommendation

All women should undergo breast cancer screening every other year starting at age 40 years, according to a draft recommendation from the US Preventive Services Task Force (USPSTF). The recommendation is a B grade and is for those who were assigned female at birth at an average risk for breast cancer.¹

“New and more inclusive science about breast cancer in [individuals] younger than 50 [years] has enabled us to expand our prior recommendation and encourage all women to get screened every other year starting at age 40,” Carol Mangione, MD, MSPH, immediate past chair of the USPSTF, said in a news release. “This new recommendation will help save lives and prevent more women from dying [because of] breast cancer.”¹

In the draft, the USPSTF concluded that the available evidence was insufficient to assess the benefits and harms of screening women who are 75 years or older. Additionally, the task force decided that available evidence was presently insufficient to determine the benefit vs harm of supplemental breast cancer screening (via breast ultrasonography or MRI) for women with dense breasts as identified by an otherwise negative screening mammogram. The USPSTF noted that these are I statements.^1,2

The recommendation applies to patients who are at an average risk of cancer; it does not apply to those with a personal history of breast cancer, those who are at very high risk of breast cancer because of known genetic markers, a history of high-dose radiation therapy to their chest at a young age, or those who have had a high-risk lesion on previous biopsies.¹

The new recommendation updates a 2016 recommendation which advised biennial screening mammography for women who were aged 50 to 74 years and individualizing the screening decision for those aged 40 to 49 years.² By lowering the screening age to 40 years, the task force believes that up to 19% more lives may be saved.¹

A systematic review conducted by the USPSTF supported the recommendation. In the review, the effectiveness of different mammography-based breast cancer screening strategiesby age to start and stop screening, screening interval, modality, use of supplemental imaging, or personalization of screening for breast cancer were assessed. They also examined the potential harms of different breast cancer screening approaches. Additionally, collaborative modeling studies conducted by the Cancer Intervention and Surveillance Modeling Network were commissioned to shed light on the benefits and harms of breast cancer screening strategies that vary by the ages to begin and end screening, screening modality, screening interval, and race.²

Findings from the review regarding the age to start or stop screening showed that screening mammography in women 40 to 49 years old had a moderate benefit in reducing the risk of breast cancer mortality. Biennial screening was found to lead to greater incremental life-years gained and mortality reduction per mammogram, with a more favorable balance of benefits to harms, according to collaborative modeling. This also showed that screening via digital breast tomosynthesis (DBT) compared with digital mammography (DM) resulted in a similar estimated benefit of approximately 5 to 6 more life-years gained per 1000 women screened.²

In terms of potential harms of screening, the USPSTF review determined that the most common harm was a false-positive result. Overdiagnosis was also identified as a potential issue, with collaborative modeling data estimating that a biennial screening strategy for persons aged 40 to 74 years would lead to 14 over diagnosed cases of breast cancer per 1000 persons screened over the lifetime of screening.²

Moreover, collaborative modeling results estimated that lowering the screening start age to 40 years from 50 years would lead to a 60% increase in false-positive results, and 2 additional over diagnosed cases of breast cancer (range, 0-4) per 1000 women over a lifetime of screening. The effect of various screening intervals on the rate of interval cancers was found to be mixed. No significant difference in the risk of interval cancer following screening with DBT vs DM.²

The USPSTF concluded with moderate certainty that biennial screening mammography in women aged 40 to 74 years has a moderate net benefit. The draft recommendation statement, draft evidence review, and draft modeling report are available for public comment on the USPSTF website until June 5, 2023.^1,2

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