Purpose: This study was conducted to evaluate the quantitative assessment of HER2/neu immunohistochemical expression in urothelial bladder cancer in order to determine its prognostic significance.
Materials and methods: Archival tumor tissue from 80 patients with primary urothelial carcinoma were analysed for HER2/neu immunohistochemical expression. A highly reproducible standardized procedure on a Bond-X automated slide stainer was used.
Results: HER2 protein was overexpressed in 41 of 80 patients (51.25%), demonstrating an increase in the expression rate corresponding to progressively advanced tumor stage (p=0.032) and tumor grade (p=0.0001). Kaplan-Meier analyses showed that positive membranous expression of HER2/neu was not associated with an increased probability of tumor recurrence (p=0.362). In contrast, HER2 scores correlated strongly with specific survival probability (p=0.002) and overall survival (p=0.025). Multivariate analysis revealed that only stage was an independent predictor of specific survival (p=0.016). HER2 expression was an independent predictor of specific survival with borderline statistical significance (p=0.08).
Conclusion: HER2 overexpression represents a prognostic factor for adverse disease outcome.