Analysis of the prognostic value of soluble epidermal growth factor receptor plasma concentration in advanced non-small-cell lung cancer patients.
Jantus-Lewintre E., Sirera R., Cabrera A., Blasco A., Caballero C., Iranzo V., Rosell R., Camps C.
BackgroundEpidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies including lung cancer. A soluble fragment of the EGFR extracellular domain (sEGFR) can be detected in the blood of patients who have non-small-cell lung cancer (NSCLC), but its clinical/ prognostic role must be further elucidated.MethodssEGFR concentration was retrospectively determined by enzyme-linked immunosorbent assay in plasma samples from 308 advanced NSCLC patients (before treatment) and 109 healthy controls and correlated with clinico-pathological variables.ResultsThe concentration of sEGFR was lower in NSCLC patients than in controls (P < .0001). sEGFR behaves as a sensitive but not specific screening biomarker. No significant associations were observed between sEGFR concentration and demographic/clinical characteristics such as gender, Eastern Cooperative Oncology Group performance status, stage, and number or location of the metastatic sites. sEGFR was lower in patients with progressive disease or in squamous cell carcinoma compared with adenocarcinoma, but these differences were not significant. Patients with sEGFR ≤ 34.56 ng/mL showed a shorter overall survival (median 9.1 versus 12.2 months, P = .019) than others. Moreover, in multivariate analysis, sEGFR remained a significant independent prognostic marker.ConclusionLow baseline sEGFR is associated with reduced survival in advanced NSCLC. Therefore, our findings in this large cohort of patients suggest that the determination of sEGFR concentration provides valuable prognostic information.