Characteristics of Overall and Cause-Specific Survival Rates in Breast Cancer Patients under the Age of 40: A Population Based Study of 481,294 Cases in SEER Registry.

Abstract

Abstract Background: Age at diagnosis has been shown to be an important prognostic factor of outcome for breast cancer (BCA). The specific aim of this study was to determine the overall survival (OS) and cause-specific survival (CSS) in young patients (<40 years old) with BCA relative to older age groups.Methods & Materials: The population of this study comprised of the 481,294 cases of women with BCA extracted from the Surveillance, Epidemiology, and End Results (SEER) registry from 1973-2006, and restaged BCA cases according to AJCC 6th edition staging system. OS and CSS were determined by the Kaplan-Meier method using R. Statistical significance was tested using the log rank or Mantel-Haenszel test in R.Results: The total 481,294 cases were categorized into the following stage groups: Stage 0 (36,692, 7.6%), I (243,460, 50.6%), II (135,013, 28.1%), III (50,233, 10.4%), and IV (15,896, 3.3%). The range of ages was from 11 to 106 (mean 60.5). Ages were divided into 5 groups: <40 (25,918, 5.4%), 40-49 (89,712, 18.6%), 50-59 (116,548, 24.2%), 60-69 (110,536, 23.0%), and >69 (138,580, 28.8%) years old. A graph of OS and tables for OS and CSS from Kaplan-Meier analysis of the entire cohort (all stages) is shown below:OS (all stages) by Age GroupAges \ OS5-year10-year15-year<40.849.764.71440-49.899.830.77550-59.890.810.72560-69.863.728.576≥70.731.479.253 CSS (all stages) by Age GroupAges \ CSS5-year10-year15-year<40.680.785.74240-49.913.859.82550-59.914.864.82560-69.916.860.814≥70.887.820.762 Both OS and CSS of each stage group shared the same trends as in the analysis of the entire cohort.Conclusion: The OS of the <40 year age group was statistically significantly better than the 60's and >69 year age groups, but worse than the 40's and 50's age groups. The CSS of the youngest age group was significantly worse than all age groups except the >69 age group. Further studies to determine contributing variables for these observatios is warranted. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2048.