Breast cancer screening guidelines issued by the U.S. Preventive Services Task Force (USPSTF) in 2009 have not led to increased or decreased breast cancer incidence, according to research published December 27 in JAMA Network Open.
A team led by Carina Zhang-Petersen, MD, from the University of Vermont in Burlington found that rates of in situ breast cancer have decreased since 2009. However, it found no evidence of more advanced breast cancer incidence or more invasive operations stemming from changes made that year to the USPSTF recommendations.
“Our results provide evidence of a decrease in in situ breast cancer incidence across all age groups since 2009, consistent with previously reported decreases in the use of breast cancer screening,” Zhang-Petersen and coauthors wrote. “Patterns in the rates of localized, regional, and distant breast cancer did not change markedly in relation to the timing of the guideline changes.”
In 2009, the task force adjusted its recommendations for breast cancer screening. It recommended that women between the ages of 40 and 49 make individualized decisions in undergoing biennial mammography screening. It also recommended that women ages 50 to 74 years undergo routine biennial screening, while women ages 75 and older were not recommended to undergo screening.
The USPSTF in 2024 re-adjusted its recommendations, saying that women in their 40s should undergo routine biennial screening, a B-grade recommendation.
Since the 2009 iteration of the USPSTF guidance, reports have suggested a reduction in mammography attendance. Radiology leaders have expressed concern that this decrease in screening could pave the way for higher breast cancer incidence and mortality rates.
Zhang-Petersen and colleagues however noted that few studies have reported changes in disease stage distribution or cancer incidence. The researchers examined trends in breast cancer stage at diagnosis and surgical treatment before and after the 2009 USPSTF guideline changes.
The study included data collected between 2004 and 2019 from 2,022,250 women in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program. Of the total, 354,263 women were in their 40s, 1,279,542 women were ages 50 to 74 years, and 388,445 women were ages 75 and older.
The team reported the following findings:
- Rates of in situ breast cancer decreased since 2009 in women ages 50 to 74 years, with an annual percentage change (APC) of –0.69.
- Localized breast cancer rates increased during the study period with an APC of 1.18 for women ages 40 to 74 years. Regional cancer rates decreased or did not change.
- Distant cancer rates remained flat since 2012 among women aged 40 to 74 years and increased among women 75 years or older during the entire study period, with an APC of 1.4.
- The proportion of women treated with partial mastectomy decreased from 2004 to 2012, with an APC of –0.77 for women aged 50 to 74 years with localized cancer. However, the proportion of women treated with total mastectomy with reconstruction increased with an APC of 20.17.
- From 2012 to 2019, the proportion of women treated with total mastectomy decreased. This included an APC of –2.44 for women aged 50 to 74 years with localized cancer. Meanwhile, the proportion of women treated with partial mastectomy increased with an APC of 1.7 for women aged 50 to 74 years.
The study authors suggested that the trend favoring partial mastectomies reflects trends observed in surgical de-escalation studies and the increase in oncoplastic reconstruction options.
They called for future studies to examine the trend of increased localized invasive breast cancer cases and decreased regional invasive breast cancer cases observed over the past two decades, including how they relate to breast cancer screening trends.
The authors added that further research will be needed to evaluate the effect of the task force’s updated breast cancer screening recommendations on breast cancer screening use and incidence patterns.
The full study can be found here.