Risk stratification using Bmi-1 and Snail expression is a useful prognostic tool for patients with upper tract urothelial carcinoma

Objectives To investigate the expression levels of E‐cadherin, Snail, Twist and Bmi‐1 in the human upper tract urothelial carcinoma, and to assess whether these factors could be prognostic markers. Methods Immunohistochemistry was carried out to determine the expression of E‐cadherin, Snail, Twist and Bmi‐1 in upper tract urothelial carcinoma samples from 144 patients that underwent total nephroureterectomy between January 1995 and December 2010. The patient population had a median age of 71 years, and comprised 104 men and 40 women, with a median follow‐up period of 40 months. The prognostic value of these markers was assessed by univariate and multivariate analysis. A risk stratification analysis was carried out. Results Snail and Bmi‐1 expression predicted worse overall survival (P = 0.0075 and 0.0035), cancer‐specific survival (P = 0.0919 and 0.0085) and recurrence‐free survival (P = 0.0360 and 0.0817, respectively) compared with tumors that lacked Snail and Bmi‐1 expression. Additionally, clinical parameters, grade, stage and lymphovascular invasion correlated with overall survival, cancer‐specific survival and recurrence‐free survival. Multivariate analysis showed that Bmi‐1 expression was among the most significant factors in predicting cancer‐specific survival (P = 0.0333). The combination of Snail, Bmi‐1 and pathological stage was the most useful prognostic biomarker for upper tract urothelial carcinoma. Conclusion Risk stratification by epithelial–mesenchymal transition and cancer stem cell‐regulated genes, such as Snail and Bmi‐1, might be useful prognostic markers for upper tract urothelial carcinoma.