Annual breast cancer screening beginning at 40 saves lives

Breast cancer is the second most common cause of cancer death for women in the U.S. Despite research showing that regular participation in screening mammography can reduce breast cancer deaths by 40%, only 50% or less Eligible women actually attend annual screenings.

“Breast cancer screening recommendations continue to be debated, particularly about when to start and the frequency of screening,” said lead researcher Debra L. Montecchiolo, MD, of the Dartmouth Geisel School of Medicine in Hanover, New Hampshire. I am a professor of radiology. .

A 2009 recommendation by the U.S. Preventive Services Task Force (USPSTF) to screen every other year, or biennially, starting at age 50, led to an increase in screening participation, Dr. Montecchiolo said. There was a decline across the country. The USPSTF drafted new recommendations in 2023, advising women to participate in biennial screening between the ages of 40 and 74. The American College of Radiology, the Society of Breast Imaging and the National Comprehensive Cancer Network recommend per annum Screening for women at average risk for breast cancer begins at age 40 and continues as long as the woman is in good health.

In the study, Dr. Montecchiolo and colleagues conducted a secondary analysis of median estimates of breast cancer screening outcomes in the Cancer Intervention and Surveillance Modeling Network (CISNET) 2023. CISNET modeling data allows researchers to estimate screening outcomes at different frequencies and starting ages using US data.

The researchers compared the benefits of screening, including reductions in mortality, years of life, breast cancer mortality, and its risks — including rates of benign, or unnecessary, biopsies and misses — for four different scenarios. : Biennial screening of women 50-74. (longstanding USPSTF recommendation), biennial screening of women ages 40–74 (new task force recommendations), annual screening 40–74, and annual screening 40–79. CISNET does not offer modeling after 79 years of age.

A review of CISNET estimates showed that annual screening with digital mammography or tomosynthesis of women aged 40–79 years reduced mortality by 41.7%. Biennial screening of women aged 50-74 and 40-74 showed a reduction in mortality of 25.4% and 30%, respectively. Annual screening of women aged 40–79 years showed the lowest false-positive screens (6.5%) and benign biopsies (0.88%) per mammogram compared with other screening scenarios.

“The main takeaway from our study is that annual screening starting at age 40 and continuing until at least age 79 has the greatest reduction in mortality, preventing most cancer deaths. , and more years of life are gained,” said Dr. Montecchiolo. “There is a huge benefit to screening annually until at least 79 and an even greater benefit if women are screened after 79.”

Although the USPSTF uses CISNET modeling to formulate its recommendations, it cites miss rates and benign biopsies as harms rather than risks, Dr. Montecchiolo said.

“To balance the harms and benefits of screening mammography, they are willing to give up some mortality benefits to avoid women being recalled for additional imaging and benign biopsies,” he said.

According to the researchers’ analyses, the probability of a woman receiving a benign biopsy after annual screening is less than 1%, and the overall recall rate for screening mammography is less than 10%. When annual screening is performed with thymus synthesis, the recall rate is reduced to 6.5%.

“The risks of screening are nonfatal and manageable for most women,” she said. “But advanced breast cancer is often fatal. Breast cancer is easier to treat if it’s found early; we can spare women additional surgeries and chemotherapy. It’s just a better idea to move to an early diagnosis.” Be done, and that’s what screening does.”

Dr. Montecchiolo said she hopes her study will add to the literature that supports annual screening at age 40 as the best method for early cancer detection.

“This paper is important because it shows once again that annual screening between the ages of 40-79 has a substantial increase in mortality benefit, and that the probability of experiencing harm on a per-screen basis is small. are,” he said. “It comes down to valuing women’s lives. I’m hoping that primary care physicians will see that the risks of screening are manageable, and the benefits are huge. We need to do this for women.”