Josh Friedman , 2025-05-02 18:00:00
Key takeaways:
- Breast cancer deaths dropped among women aged 20 to 49 years between 2010 and 2020.
- Ten-year survival rates varied based on race, ethnicity, age and molecular subtype.
Breast cancer deaths decreased among women aged 20 to 49 years from 2010 to 2020, with dramatic reductions occurring in the latter part of the decade, according to results presented at American Association for Cancer Research Annual Meeting.
Deaths declined across all racial and ethnic groups and age groups, though disparities remained.
Adetunji T. Toriola
“We have made tremendous advances in reducing mortality from breast cancer in young women but there are still opportunities for improvements, especially in relation to eliminating disparities,” Adetunji T. Toriola, MD, PhD, MPH, professor of surgery at Washington University School of Medicine in St. Louis and co-lead of the cancer prevention program at Siteman Cancer Center, said in a press release.
‘Similar trends’
In 2024, Toriola and colleagues published a paper in JAMA Network Open that showed breast cancer incidence rates increased 0.79% yearly among women aged 20 to 49 years between 2000 and 2019.
However, incidence increased steadily from 2000 to 2016 (annual percentage change = 0.24) and more dramatically from 2016 to 2019 (APC = 3.76).
Incidence rates increased across various racial, ethnic and age groups, as well.
“When we saw this, we wanted to see whether there’d been similar trends in mortality, because we know that factors that drive incidence differ from factors that drive mortality,” Toriola said during his presentation.
Researchers used the SEER Program 17 registry to investigate these trends among women aged 20 to 49 years between 2010 and 2020.
They included 112,826 diagnoses of primary invasive breast cancer and 11,661 breast cancer-specific deaths (66.2% aged 40-49 years; 47.1% white; 52.3% luminal A) in their study.
Incidence-based mortality (IBM) rates based on race, ethnicity, age and molecular subtype served as the primary endpoint.
10-year trends
IBM decreased from 9.7 per 100,000 women in 2010 to 1.47 per 100,000 in 2020.
Deaths declined across all racial and ethnic groups. The greatest reduction occurred among Black women (16.56 per 100,000 to 3.41), followed by American Indian and Alaska Native (10.84 to 1.38), white (9.18 to 1.16), Hispanic (8.46 to 1.25) and Asian or Pacific Islander (7.53 to 1.27).
Annual percentage changes grew substantially larger for all races during the decade.
IBM declined across most racial groups: 6.77% from 2010 to 2016 and 24.15% from 2016 to 2020 among Black women; 8.54% from 2010 to 2017 and 33.27% from 2017 to 2020 among white women; 7.23% from 2010 to 2018 and 47.97% from 2018 to 2020 among American Indian and Alaska Native (AIAN) women; and 8.69% from 2010 to 2017 and 30.15% from 2017 to 2020 among Hispanic women.
However, IBM increased among Asian or Pacific Islander (API) women 0.83% from 2010 to 2013 and declined 18.46% from 2013 to 2020.
The study population had a 10-year survival rate of 85.3%, but variation occurred across subgroups.
Women aged 40 to 49 years had a higher 10-year survival rate than women aged 20 to 39 years (87.6% vs. 78.5%), and API (88.2%) and white women (88%) had higher rates than AIAN (84.5%), Hispanic (81.7%) and Black women (75.5%).
Toriola noted guideline-recommended screening for women aged 40 to 49 years may have an impact on the difference in 10-year survival rates.
“Lower 10-year survival among women aged 20 to 39 compared to women aged 40 to 49 highlights the need for targeted screening in high-risk populations who are [younger] than 40 years,” Toriola said.
Women with triple-negative breast cancer had the lowest 10-year survival rates across age groups and racial and ethnic groups.
Women with luminal A had the highest 10-year survival for women aged 40 to 49 years and white women, and those with luminal B had the highest 10-year survival for women aged 20 to 39 years, Hispanic and Black women.
Toriola described the difference in 10-year survival for luminal B vs. luminal A (84.2% vs. 78.3%) for women aged 20 to 39 years as “unexpected” and worth future research.
“We think in younger women — between age 20 and 29 — we may just have a more aggressive type of tumor,” he said. “We’re wondering whether it’s the HER2-negative component in these women that makes them more resistant to current therapy, but that’s still a hypothesis.”
References:
Sources/Disclosures
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Toriola AT, et al. Abstract 6207. Presented at: American Association for Cancer Research Annual Meeting; April 25-30, 2025; Chicago.
Disclosures:
Toriola reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
