Abstract P2-14-04: Effect of age at the time of diagnosis on overall and cancer-specific mortality in breast cancer: Analysis of SEER, 1990-2008

Abstract

Abstract Background: As a critical factor, age at the time of diagnosis has a significant impact on cancer therapy and outcomes. The purpose of this study is to investigate the overall mortality (OM) and breast cancer-specific mortality (BCSM) in patients with breast cancer corresponding to age at the time of diagnosis, thus constructing an age-related pattern on breast cancer survival. Methods: We analyzed data for 396,978 women aged 20-79 from 1990 to 2008 diagnosed with breast cancer from the population-based Surveillance, Epidemiology, and End Results (SEER) program of the U.S. national cancer institute. Clinicopathological factors and outcomes were compared using a chi-square test, the Kaplan-Meier method, and Cox proportional hazards regression model. Results: In the multivariable analysis, a significant relationship was found between age at the time of diagnosis and OM (p<0.001) as well as BCSM (p<0.001). Using 70-79 years old as the reference, the hazard ratio (HR) of OM and BCSM presents a U-like shape with the bottom at the group 40-49 years old (OM: HR,0.56; P<0.001; BCSM: HR,0.58; p<0.001) and 50-59 years old (OM: HR,0.59; P<0.001;; BCSM: HR,0.60; p<0.001), increasing to both ends gradually. Analysis in subgroup according to ER and PgR status, group 20-29 years old showed no significant difference with group 70-79 years old on both OM and BCSM in all subgroups except on BCSM in ER+PR+ subgroup (HR,1.25; P = 0.002). Conclusion: Patients at very young and very old age (20-29 years old and 70-79 years old) have the poorest outcomes while prognosis improves with age towards mean level. The very young age (20-29 years old) may be regarded as a significant hazard factor for BCSM in patients with ER+PR+ breast cancer. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-14-04.