Prognostic significance of epidermal growth factor receptor expression in colon cancer patients undergoing curative surgery

Background: To investigate the role of epidermal growth factor receptor (EGFR) expression as a prognostic marker for prediction of cancer behavior and clinical outcomes in colon cancer patients undergoing potentially curative surgery. Methods: EGFR determination using a commercially available immunohistochemistry kit was performed in tissues from 149 colon cancer patients receiving primary surgical treatment and in 25 normal colon mucosa specimens from noncancer patients. EGFR positivity was correlated in univariate and multivariate analyses with disease recurrence and survival. In addition, p27, p53, and vascular endothelial growth factor expression were assessed by immunohistochemistry in 104 patients and correlated with EGFR tumor expression and clinical outcome. Results: EGFR expression was detected in approximately one third of colon cancer patients (53 of 149; 35.6%). In 126 curatively treated patients, EGFR expression was correlated with disease recurrence and worse survival in both univariate and multivariate analyses. In a multivariate model for predicting recurrence and survival, Dukes' staging, p27, and EGFR expression were the only independent covariates. In particular, in Dukes' A and B patients the 5-year survival probability was 96% for EGFR-negative and high p27 expression cases and was 30.7% for EGFR-positive and low p27 expression cases. Conclusions: EGFR expression was an independent prognostic indicator of disease recurrence and poor survival in colon cancer patients undergoing curative surgery. In the context of novel therapeutic options such as molecularly targeted therapies, these findings suggest that anti-EGFR drugs could be evaluated in the adjuvant treatment of EGFR-positive colon cancer patients.