Prognostic role of epidermal growth factor receptor in localized breast cancer: 15 Years of follow-up

Background: The expression of epidermal growth factor receptor (EGF-R) in breast cancer (BC) is generally considered as an unfavorable event during tumor progression. Its predictive role has been fairly well defined: EGF-R expression predicts tamoxifen unresponsiveness. EGF-R role in autocrine growth regulation was confirmed. However, reported results on its prognostic role in BC patients were conflicting. The prognostic role of EGF-R after 15 years of follow-up is analyzed in a group of 70 localized BC patients, presented at diagnosis in clinical stages I-III. Methods: BC patients newly diagnosed from December 1990 until March 1991, treated in accordance to the National Protocol, were selected for EGF-R analysis. Steroid receptors and EGF-R were determined at diagnosis in same frozen tissue samples, using biochemical methods. Except 6 patients who were lost from follow-up in the interval shorter than 60 months, the remaining patients were followed-up from 60-188 months. The total number of events was 32 relapses (46%), and 27 deaths (38.5%). Results: EGF-R expression was found in 28/70 patients (40%), and the EGF-R content higher than 26 fmol - in 15/70 patients (21%). Neither the expression, nor the high content of EGF-R showed any influence on disease-free or overall survival. Levels of EGF-R were similar in relapsing and relapse-free patients. Nodal status had the strongest infuence on prognosis. Conclusion: Our results suggest that the controversial findings, regarding the EGF-R prognostic role, might be the consequence of a genuine weak influence of EGF-R expression on disease outcome. .