Over-expression of HER-2 is associated with the stage in carcinomas of the urinary bladder
Background: The frequency of over-expression of human epidermal growth factor receptor-2 (HER-2) in bladder cancer is one of the highest among all human malignancies. This over-expression is thought to play a role in aberrant proliferation of cancer cells. Studies on HER-2 expression in bladder carcinoma have shown heterogeneous results.
Purpose: The aim of the study was to evaluate the status of HER-2 protein expression in patients with invasive carcinomas of the urinary bladder as related to tumor grade and stage.
Materials and methods: Archival samples from 39 patients (6 women, 33 males) with urinary bladder cancer were analyzed for HER-2 over-expression, using immunohistochemistry with the HercepTest. Results: HER-2 over-expression was observed in 23/39 tumors (59%) and was more frequent in high-grade than in low-grade carcinomas, but the difference was not statistically significant. A significant correlation was established between HER-2 over-expression and tumor stage (p=0.011). HER-2 expression was more frequent in transitional cell carcinomas (TCC) and adenocarcinomas (AC) as compared with squamous cell carcinoma (SCC). Patients’ age and sex were not related to HER-2 over-expression.
Conclusion: Over-expression of HER-2 was frequent in carcinomas of the urinary bladder. Knowing the HER-2 status would be helpful in formulating a rational treatment strategy for patients with urinary bladder cancer.
Keywords: bladder cancer; human epidermal growth factor receptor-2; immunohistochemistry; over-expression