Improvement of Survival in Patient with Primary Metastatic Breast Cancer over a 10-Year Periode: Prospective Analyses Based on Individual Patient Date from a Multicenter Data Bank

Abstract

Approximately 6% of patients with breast cancer have distant metastases at the time of the initial diagnosis. The aim of this analysis was to examine the overall survival rate over time and to investigate the effect of new therapy options. Methods : This retrospective analysis was performed based on the data bank of the Clinic for Gynaecological Oncology/Dr. Horst Schmidt Klinik, Wiesbaden and the Clinic for Gynaecological Oncology and Senology/Kliniken Essen Mitte, Essen. The patients with primary metastatic breast cancer (pmBC) who were diagnosed and treated at the accredited breast cancer centres of these clinics were enrolled between 1998 and 2007. The date of diagnosis was used to define 2 specifically chosen 5-year periods: 1998-2002 and 2003-2007. The follow-up time was on average 76 months. The Breslow Test was used to evaluate changes in the median survival time and to detect factors associated with the increase in survival rates. Results : Two hundred sixteen patients with complete baselines were analysed. Ninety patients were diagnosed between 1998 and 2002, and 126 patients received their diagnosis of pmBC between 2003 and 2007. The tumour-biological factors were the same in both groups, whereas the therapeutic concepts were different —the later group (2003-2007) received more aromatase inhibitors, taxane-based chemotherapy and trastuzumab. This finding resulted in an increased median survival time from 31 months in the years 1998-2002 to 44 months in the group with the first diagnosis between 2003 and 2007. Conclusions: Primary metastatic breast cancer occurred at constant rates over last 10 years. The tumour findings did not change in the time between the two examined groups; however, the treatment options in the 2003-2007 group included newly approved therapies. The time period of the first diagnosis was detected as a risk factor for overall survival. Those patients diagnosed in the more recent time frame had a significantly improved survival rate. The establishment of new therapy options may explain this finding.