[Plasma E-cadherin levels in urinary bladder cancer: does it improve risk stratification?].

BACKGROUND: Urinary bladder cancer represents a heterogeneous group of cancers regarding their clinical behaviour. For patients with muscle-invasive bladder cancer the 5-year disease-specific survival rate is only 50%. The main cause of death in this patient group is rapid metastatic progression following surgery. Clinicopathological features provide only limited information to predict disease progression in these patients. E-cadherin is a transmembrane glycoprotein critically involved in epithelial cell adhesion. Elevated circulating E-cadherin levels were shown to be correlated with progression of bladder cancer. MATERIAL AND METHODS: Plasma E-cadherin levels of 97 patients and 17 controls were analysed using an enzyme-linked immunosorbent assay, and results were compared with the clinical follow-up data. RESULTS: Plasma E-cadherin concentrations were significantly higher in patients than in controls (p<0.001). E-cadherin levels were not significantly correlated with clinicopathological parameters such as tumour stage (p=0.196), grade (p=0.570) and lymph node status (p=0.581). In a subgroup of patients treated by radical cystectomy, E-cadherin concentrations were higher in lymph node-positive cases; however, this correlation (p=0.100) failed to reach statistical significance. Furthermore, plasma E-cadherin levels were not able to predict disease-specific survival or metastasis-free survival (p=0.512 and p=0.197). CONCLUSIONS: Our results suggest that soluble E-cadherin levels are not able to predict patients' prognosis and underline the importance of external validation in prognostic marker research. Molecular markers predicting disease progression after radical cystectomy to identify high-risk patients and improve therapy decisions are still needed.