Introduction: Previous studies have suggested that young breast cancer patients have poorer survival as compared with their older counterparts. Most of this research reflects single institution experiences that may not be representative of the population. This study was designed to determine whether young breast cancer patients have poorer survival as compared with an older cohort using a national population-based cancer registry and, more specifically, to determine whether differences in survival are caused by more advanced tumor stage, more aggressive disease, or patient-specific characteristics.
Materials and methods: Using the Surveillance, Epidemiology, and End Results cancer database (1992-1998), data for all patients with a diagnosis of invasive breast cancer were extracted. Two age categories were analyzed: young group (<or=35 years old, n = 4616) and older group (50-55 years old, n = 20319). Patient demographics, 5-year survival rates, tumor characteristics (stage, grade, and receptor status), surgical treatment, and use of radiation were compared between the groups.
Results: Overall, young patients had worse 5-year survival when compared with the older group (74.3% vs. 85.1%). Stage for stage, the young patients also had poorer survival (except for stage IV). They present with more advanced stage disease and have more aggressive tumor characteristics, that is, higher grade tumors and more estrogen- and progesterone receptor-negative tumors. Even after controlling for patient characteristics, tumor factors, and receipt of treatment, a multivariate regression showed that young age was an independent risk factor for death (HR = 1.095).
Conclusions: Young breast cancer patients have poorer outcomes, which are in part attributed to later stage disease, more aggressive tumors, and less favorable receptor status. There still appears to be other important factors, not included in our study, that are contributing to the worse outcomes for these young patients, such as socioeconomic status. Physicians need to have heightened awareness when evaluating this population, and increasingly efficacious adjuvant therapies need to be developed.