E-cadherin expression in upper urothelial carcinoma in Balkan Endemic Nephropathy and non-endemic regions.

There is a high incidence of upper urothelial carcinoma (UUC) in regions affected by Balkan Endemic Nephropathy (BEN). The aim of this study was to compare E-cadherin expression in UUC, in regions affected by BEN, and in control rural and city populations free of BEN. Another aim was to determine the influence of some morphological parameters on the E-cadherin status. In the samples of 85 UUC patients, of whom 40 lived in BEN settlements and 45 served as control subjects, immunoreactions were performed using monoclonal anti-human E-cadherin antibody. Aberrant expression of E-cadherin was more frequent in BEN tumors than in control tumors (p<0.01). Decreased E-cadherin expression was linked to high grade and solid growth in control and BEN tumors (p<0.0001 and <0.05 versus p<0.05 and <0.05, respectively), and to the stage in control tumors (p<0.01). However, BEN low grade and low stage tumors showed aberrant expression more often than did control tumors (p<0.05 and <0.005, respectively). In control tumors, using univariate analysis, E-cadherin status was found to be influenced by grade, stage, and tumor growth (p=0.001, 0.017, 0.015, respectively). In the same group, only the grade was significant according to multistep logistic regression analysis (Wald=6.429 and p=0.011). The growth pattern had a predominant influence on E-cadherin expression in BEN tumors (p=0.005). A significant influence on normal membranous or abnormal cytoplasmic expression of E-cadherin in UUC is exerted by tumor grade, stage, growth, and metaplastic change (p=0.002, 0.048, 0.019, 0.011, respectively), but only by tumor grade in the multistep logistic regression model. These results suggest that decreased expression of E-cadherin in BEN tumors may be linked to tumor growth, while expression of E-cadherin in control tumors may be associated with tumor grade.