Annual mammography starting at age 40 leads to greatest reduction in breast cancer deaths
Annual screening mammography beginning at age 40 years resulted in a greater reduction in breast cancer mortality than two other screening strategies, according to a computer modeling study.
“Our findings are important and novel because this is the first time the three most widely discussed recommendations for screening mammography have been compared head-to-head,” Elizabeth Kagan Arleo, MD, assistant professor of radiology at Weill Cornell Medicine and assistant attending radiologist at NewYork-Presbyterian Hospital, said in a press release.
“Our research would be put to good use if, because of our findings, women chose to start annual screening mammography starting at age 40,” Arleo added. “Over the long term, this would be significant because fewer women would die [of] breast cancer.”
The age at which women should begin breast cancer screening has been the subject of considerable debate.
The U.S. Preventive Services Task Force in 2016 reiterated its recommendation of biennial screening mammography for women aged 50 to 74 years. The decision to start screening mammography earlier than age 50 years should be an individual one, according to the task force.
The American Cancer Society suggests women with an average risk for breast cancer undergo regular screening mammography beginning at age 45 years, and that women aged 40 to 45 years should have the opportunity to begin screening. The society recommends women transition to biennial screening age 55 years but have the option to continue annual screening.
Arleo and colleagues aimed to assess differences in the effects of various recommendations.
Investigators used mean values of six Cancer Intervention and Surveillance Modeling Network breast cancer-specific computer models to evaluate the three most widely discussed screening strategies for women at average risk for breast cancer:
lAnnual screening from age 40 years to age 84 years;
lA hybrid screening approach that calls for annual screening from ages 45 to 54 years, followed by biennial screening from ages 55 to 79 years; and
lBiennial screening from ages 50 to 74 years.
Researchers calculated mean mortality reductions for each of the three approaches.
They determined annual screening from age 40 years to age 84 years would result in a 39.6% reduction in breast cancer-specific deaths.
The hybrid screening approach would reduce breast cancer-specific mortality by 30.8%, and biennial screening starting at age 50 years would reduce breast cancer-specific deaths by 23.2%, according to modeling results.
Researchers applied their modeling to a single-year cohort of 2.46 million U.S. women aged 40 years who were born in 1960 and alive in 2000.
For this cohort, assuming 100% compliance, more breast cancer deaths would be avoided through annual screening beginning at age 40 years (n = 29,369) than through the hybrid approach (n = 22,829) and the biennial screening-only approach (n = 17,153).
Annual screening beginning at age 40 years also would result in the most life-years gained (189 years per 1,000 women), followed by the hybrid approach (149 years per 1,000 women) and the biennial screening-only approach (110 years per 1,000 women).
However, for the single-year cohort, annual screening beginning at age 40 years would result in the greatest total number of mammographic examinations (90.2 million, compared with 49 million for the hybrid approach and 27.3 million for the biennial-only approach), total number of negative recalls (6.8 million, compared with 4.1 million for hybrid and 2.3 million for biennial) and total number of benign biopsies (481.269, compared with 286,288 for hybrid and 162,888 for biennial).
“Our results show the differences in the three current recommendations for screening mammography in terms of benefits and risks,” researcher R. Edward Hendrick, PhD, clinical professor of radiology at University of Colorado School of Medicine, said in the release. “Women and their physicians can use these findings to guide choices of when a woman begins screening mammography and how often she gets screened.” – by Melinda Stevens
Disclosures: Arleo and Hendrick report no relevant financial disclosures. Please see the full study for a list of all other researchers’ relevant financial disclosures.