Pilot Study of the Clinical Significance of Serum and Urinary HER-2/neu Protein in Bladder Cancer Patients

PURPOSE: HER-2/neu overexpression is documented in some bladder cancers. To our knowledge, there are no current studies evaluating urine HER-2/neu levels. Therefore, we examined the clinical significance of serum and urine HER-2/neu protein in bladder cancer. MATERIALS AND METHODS: Urothelial bladder carcinoma patients (n=38, including 31 men and 7 women) and healthy controls (n=25, including 20 men and 5 women) were included in the study. Urine cytology and serum and urine HER-2/neu levels were measured before the transurethral resection of bladder tumor procedure. Prognostic factors including tumor stage, histologic grade, tumor size, multiplicity, and preoperative urine cytology and their association with urinary HER-2/neu were analyzed by simple and multiple regression analyses. RESULTS: There was no significant difference in serum HER-2/neu between the two groups (p=0.489). The mean urinary HER-2/neu was 7,586.82 relative luminescence unit (RLU) in bladder cancer patients and 4,245.84 RLU in healthy controls. The mean RLU values of urinary HER-2/neu in the bladder cancer patient group were significantly higher than in healthy controls (p=0.012). An receiver operating characteristic curve was generated, and using the cutoff value of ≥4,800 RLU of urinary HER-2/neu, 71.1% sensitivity and 84.0% specificity were obtained. Among the clinical factors, only positive preoperative urine cytology samples were associated with urinary HER-2/neu levels by both simple and multiple regression analyses. CONCLUSIONS: Bladder cancer patients demonstrated significantly higher urinary HER-2/neu than did healthy controls. These findings suggest that urinary HER-2/neu may be valuable as a new urinary marker. The application of urinary HER-2/neu needs additional investigation.