A recent study analyzed data from the SEER Program 17 registry, which included 11,661 breast cancer deaths among women aged 20 to 49, focusing on various subtypes such as luminal A, luminal B, triple-negative, and HER2-mutated breast cancer.

The improvements in breast cancer mortality rates are attributed to advancements in precision medicine, increased access to screening, and the adoption of therapies like endocrine therapy and CDK4/6 inhibitors, which gained FDA approval starting in 2015.

Between 2010 and 2020, breast cancer mortality among women aged 20-49 significantly decreased across all subtypes and racial/ethnic groups, with notable declines starting after 2016.

The largest drop for luminal A breast cancer occurred in 2017, with a 32.88% annual percent change (APC), while triple-negative breast cancer saw its steepest decline in 2018 at 32.82% APC.

Despite these improvements, disparities in survival outcomes remain, particularly for non-Hispanic Black women, who had the highest incidence-based mortality rates and the worst survival outcomes.

The 10-year relative survival rates for luminal A breast cancer varied by age, with women aged 40-49 having a survival rate of 78.3%, compared to 84.2% for luminal B in younger women aged 20-39.

These findings underscore the need for further research and equitable care strategies to address ongoing disparities in breast cancer survival outcomes among different racial and ethnic groups.

Dr. Toriola emphasizes the importance of continued impactful research to further reduce breast cancer mortality, improve understanding of tumor biology in younger women, and promote access to screening and high-quality treatment.

Future research should focus on tumor biology, molecular mechanisms, and ensuring access to screening and high-quality care for all women, particularly those at higher risk.

Non-Hispanic Black women had the highest incidence-based mortality rates in both 2010 and 2020, while non-Hispanic white women had the lowest rates.