Statistical analyses

Chi-square test was used to assess N-cadherin expression with categorical variables. Differences in continuous variables were analysed using Mann–Whitney U test. The Kaplan–Meier method was used to estimate recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS); log-rank tests were applied for pairwise comparison of survival. Univariable and multivariable Cox regression models addressed associations of disease recurrence, cancer-specific mortality and overall mortality with potential prognostic factors. All p values were two-sided, and statistical significance was defined as p < 0.05. Statistical analyses were performed using Stata 11.0 statistical software (StataCorp., College Station, TX, USA).