The role of squamous differentiation in patients with transitional cell carcinoma of the bladder treated with radical cystectomy.

OBJECTIVE We aim at determining the prognostic value of squamous differentiation in patients with transitional cell carcinoma (TCC) of the bladder that were treated with radical cystectomy. MATERIALS AND METHODS From January 1993 to January 2005, we retrospectively selected 113 patients. Correlations among squamous differentiation with other clinical and pathological features were assessed by both chi-square and Fisher tests. The Kaplan-Meier method was used to evaluate survival curves and statistical significance was determined by the log-rank test. Multivariate analysis was performed through a Cox proportional hazards regression model. RESULTS Squamous differentiation was observed in 25 (22.1%) of the 113 patients. This finding was significantly related only to the pathological stage. Mean follow-up after cystectomy was 31.7 +/- 28.5 months. Disease recurrence occurred in 16 (64%) and 30 (34%) patients with and without squamous differentiation (log-rank test, p = 0.001), and mortality occurred in 10 (40%) and 14 (16%) of the patients with and without squamous differentiation respectively. Univariate analysis revealed that pathological stage, squamous differentiation, tumor size and lymph node involvement were significant predictors of cancer-specific survival. However, only squamous differentiation and tumor size were independent prognostic variables on multivariate analysis. CONCLUSIONS Squamous differentiation was an independent prognostic factor for cancer specific survival in patients with bladder cancer treated with radical cystectomy. Further studies with a larger number of patients are necessary to confirm these results.