Prognostic significance of Her2/neu overexpression in patients with muscle invasive urinary bladder cancer treated with radical cystectomy

Abstract

The aim of the study was to evaluate the status of Her2/neu protein expression in patients with muscle-invasive urothelial carcinomas of the bladder treated with radical cystectomy and to determine its prognostic significance. We retrospectively analyzed the data of 90 patients who had undergone cystectomy for invasive transitional cell carcinoma of the urinary bladder. Immunohistochemical analysis for Her2/neu was done on paraffin-fixed tissues with CB11 antibodies (BioGenex, San Ramon, CA, USA). Sections with grade 2 and grade 3 staining were considered positive for Her2/neu. Over a median follow-up period of 46 months (24-96 months) 46 patients are living without disease recurrence and six with recurrent disease either at the local site or with distant metastases. The remaining 38 patients have died. The median overall survival time was 50 months, and median disease-free survival time was 40 months. The Her2/neu status was significantly related to the tumor stage (P = 0.001), lymph node involvement (77% in N+ vs 23% in N0; P = 0.001) and the grade of the disease (32% of grade 2 vs 71% of grade 3; P = 0.037). Kaplan-Meier curves showed a significantly worse disease-related survival period (log rank P = 0.011) for patients with Her2 overexpressing tumors than for those without overexpression. In addition to tumor stage [P = 0.001; relative risk (RR) = 2.62] and lymph node status (P = 0.0001; RR = 2.95), Her2 status (P = 0.020; RR = 2.22) was identified as an independent predictor for disease-related survival in a multivariate analysis. These results suggest that Her2 expression might provide additional prognostic information for patients with muscle-invasive bladder cancer. Future studies on Her2 expression with chemosensitivity and the efficacy of Her2-targeted therapies in urothelial carcinomas are warranted.