OBJECTIVE: Modifications in E-cadherin (E-Cad) expression are associated with dedifferentiation, progression, metastases and poor prognosis in many types of tumors. The aim of the present study was to identify a potential association of the pre- and post-operative soluble E-Cad levels (sE-Cad) with the clinicopathological parameters of patients with gastric cancer.PATIENTS AND METHODS: Serum sE-Cad levels were determined in 99 gastric cancer patients and 78 healthy volunteers using ELISA.RESULTS: Levels of sE-Cad were significantly increased in gastric cancer patients compared with these levels in healthy controls (p < 0.001). For the evaluation of the diagnostic significance of sE-Cad the area under the receiver operating characteristic (ROC) curve (AUC) was 0.835, while the optimal cut-off point of 9.9 microg/mL was determined to classify gastric cancer patients, which yielded sensitivity of 72.7%, specificity of 80.8% and accuracy of 76.3%. Poor differentiation (p = 0.009) and the presence of distant metastases (p < 0.001) were the two significant independent prognostic determinants for high sE-Cad levels in multivariate linear regression analysis. The preoperative levels of sE-Cad also proved helpful in classifying patients according to the choice treatment (curative versus palliative) (AUC, 0.656); when the optimal cut-off point was set at 17.60 microg/mL, the sensitivity was 57%, the specificity was 83% and accuracy was 75%. Survival was shorter in patients with increased sE-Cad (median, 7 months vs 39 months, p = 0.0002), although multivariate Cox regression analysis demonstrated a marginal prognostic significance of sE-Cad for survival (adjusted HR = 1.68, 95% CI = 0.93 to 3.02, p = 0.072).CONCLUSIONS: Serum sE-Cad levels could be considered as a diagnostic and prognostic marker in gastric cancer patients as well as a tool to select a treatment approach. The prognostic value of sE-Cad on overall survival requires further study.