ERBB2 and urothelial carcinoma: The present study was conducted to investigate the expression of EGFR and HER2 proteins, as well as intracellular signaling molecules in sections of urothelial carcinomas by immunohistochemistry, to analyze e-cadherin, p-cadherin, and b-catenin expression in low and high grade urothelial carcinomas, and to correlate the immunohistochemical results with clinicopathologic parameters.