Predicting the prognosis of patients with bladder carcinoma is demanding, as staging and grading alone do not suffice to make a precise assessment. Thus, the prognostic relevance of various molecular factors was analyzed. It has recently been postulated that gene amplification of serine threonine kinase 15 (STK15) in normal urothelium is of prognostic value in muscle-invasive bladder cancer. The aim of the present study was the validation of these findings. We retrospectively analyzed amplification of STK15 gene in normal urothelium of 68 patients having undergone radical cystectomy for urothelial bladder carcinoma of the bladder at our department between 1998 and 2006 with available paraffin specimens. A tumor micro array (TMA) was constructed, and fluorescence in situ hybridization (FISH) was performed. Signals of chromosome 20 and STK15 gene were counted using fluorescence microscopy. Specimens of 48 patients could be evaluated. The median follow-up was 20 months [2-106 months]; disease-specific death occurred in 7 patients (15%). There was no amplification of STK15 gene in normal urothelium of cystectomy specimens. In contrast to the preceding study, the present data show no STK15 gene amplification in normal urothelium of cystectomy specimens. Prediction of the oncological outcome warrants further research of different markers.