Serum levels of hepatocyte growth factor (HGF) and epidermal growth factor (EGF) as prognostic factors in malignant pleural mesothelioma (MPM)

Abstract

10080 Background: MPM is an uncommon but extremely aggressive tumor of the serosal surfaces, which has been closely linked to asbestos exposure. Several in-vitro studies have demonstrated that HGF enhances MPM cell proliferation, migration, and invasiveness and the presence of EGF is closely related to the process of cell differentiation and the synthesis of glycosaminoglycans in MPM cells. Few studies have measured the blood levels of these growth factors in tumor patients and assessed their correlation with clinical outcome. This pilot study was designed to investigate the potential value of serum EGF and HGF measurements for the diagnosis and the prediction of survival in MPM patients. Methods: Baseline serum EGF and HGF levels (ng/ml) were determined using an ELISA method in 81 newly diagnosed MPM patients (mean age 67.5±11.0 years) and 48 patients with benign respiratory diseases (BRD; mean age 64.3±13.5 years). Results: HGF and EGF median concentrations in MPM (1.6 ng/ml and 0.5 ng/ml, respectively) were not statistically different from concentrations in BRD (1.2 ng/ml and 0.4 ng/ml). Median follow-up for MPM patients was 27 months, while overall median survival was 11.8 months. At univariate analysis, only high EGF serum levels were associated with an unfavorable survival outcome. Using a cut-off point for EGF of 0.5 ng/ml (corresponding to the median of marker concentration in MPM), the survival rate in patients with higher serum EGF was significantly worse than that in patients with lower levels (median 10.7 vs. 13.0 months, p=0.01). Multivariate analysis, after adjusting for age, sex, histology and platelet count, confirmed the independent predictive value of serum EGF concentration as a negative prognostic factor (p=0.01). Conclusions: High pre-treatment levels of serum EGF are associated with an adverse prognostic impact on survival in MPM patients. No significant financial relationships to disclose.