Survival among women age 40 years and younger with breast cancer appears to vary according to breast cancer subtype, with age particularly prognostic for women with luminal type breast cancers, a study published in the Journal of Clinical Oncology has shown.1
Previous studies demonstrate a relationship between higher risk of disease recurrence and death in women age 40 years and younger with early stage breast cancer; however, the impact of tumor subtype on outcomes has not been adequately addressed. Using Multivariable Cox proportional hazards models, researchers assessed the association between breast cancer–specific survival and age at diagnosis.
For the study, data from 17,575 women with newly diagnosed stage I to III breast cancer presenting to 1 of 8 National Comprehensive Cancer Network centers between January 2000 and December 2007 were reviewed; median follow-up was 6.4 years. Of the women eligible for analysis, 1916 were 40 years or younger at diagnosis.
Results showed breast cancer mortality was higher in the younger women (hazard ratio [HR], 1.4; 95% CI, 1.2 to 1.7) in Multivariable Cox proportional hazards model controlling for sociodemographic, disease, and treatment characteristics.
In stratified analyses, statistically significant increase in risk of death was seen in younger women with luminal A (HR, 2.1; 95% CI, 1.4 to 3.2) and luminal B (HR 1.4; 95% CI, 1.1 to 1.9) type tumors. Age had borderline significance among women with triple-negative tumors (HR, 1.4; 95% CI, 1.0 to 1.8) but not among women with HER2 subtype (HR, 1.2; 95% CI, 0.8 to 1.9). An additional model controlling for detection method found risk of death significantly higher only in younger women with luminal A tumors.
1. Partridge AH, Hughes ME, Warner ET, et al. Subtype-dependent relationship between young age at diagnosis and breast cancer survival. J Clin Oncol. 2016 Aug 1. doi: 10.1200/JCO.2015.65.8013. [Epub ahead of print]