Long presented as a cancer mainly linked to age, breast cancer today shows a different face among American women. A large study reveals that the breast cancer mortality is shifting toward younger women, while survival among older patients is clearly improving.
Conducted by Houston Methodist, the study published in npj Breast Cancer was directed by Stephen Wong. “Rising mortality among younger women, while survival improves among older women, shows breast cancer risk is changing“, he explains. “Importantly, we found that Asian women under the age of 50 experience worse outcomes and face higher mortality risk than previously described.“, he continues.
A large study examining cases of breast cancer over 50 years
The researchers used data from the Surveillance, Epidemiology and End Results registry over the period 1975-2022, almost five decades of monitoring. They observe that deaths, once concentrated among older women, increasingly weigh on younger generations, while older patients benefit much more from advances in screening and treatment.
Looking more closely at the recent period 2010-2022, the team combined age, ethnicity and tumor subtype. The authors describe more aggressive tumors in young women and cite a mixture of biological, hormonal, demographic and access to care factors to explain the survival differences observed.
Young women, triple negative and origin: the most exposed profiles
Among those under 50, black women with cancer triple negative remain, as expected, the most exposed group. This subtype lacking hormone receptors and the HER2 protein offers few targeted options and progresses quickly, which translates into a particularly high risk of death in the study.
The study also describes elevated risks among Asian and Hispanic women under 50, especially when an aggressive subtype like triple-negative is involved, with worse-than-expected outcomes for Asians.
“Age, ethnicity, and tumor type should not be considered separately, as they interact and cause these disparities“, says Lin Wang, of Houston Methodist. “By analyzing them together, we highlight risks that would otherwise remain unsuspected.“, she adds.
SEER registries finally show that Asian and Hispanic women now outnumber black patients in this cohort, which highlights the major demographic shift in the prevalence of breast cancer.
What these results change for women under 50
For Lin Wang, these observations should lead to “age-aware, subtype- and population-specific approaches” for research, screening and care. The message is simple for those under 50: this cancer is not reserved for mothers or grandmothers, and any unusual changes in the breast deserve a medical consultation.