title: Prostate stem cell antigen predicts tumour recurrence in superficial transitional cell carcinoma of the urinary bladder.
abstract: OBJECTIVE
  To evaluate the relationship between prostate stem cell antigen (PSCA) expression level in transitional cell carcinoma (TCC) of the urinary bladder and various clinicopathological features, including stage and grade; and to determine whether PSCA mRNA expression predicts disease recurrence in superficial (not muscle-invasive) TCC of the bladder.
  
  
  METHODS
  Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was performed on 97 TCC tissue samples and in 36 samples of normal bladder urothelium; the findings were analysed in relation to clinicopathological factors. Immunohistochemical expression was examined using light and confocal immunofluorescence microscopy to validate the RT-PCR data.
  
  
  RESULTS
  Twenty-seven patients developed disease recurrence, while the remaining 22 had no evidence of recurrence of superficial TCC of the bladder. There was significantly higher PSCA mRNA expression in TCC than in normal urothelium samples (P = 0.008). Superficial (TaT1) tumours had significantly higher PSCA expression than muscle-invasive (> or = pT2) tumours (P < 0.001). There was no significant difference between patients with G1-2 tumours and those with G3 tumours (P = 0.109). Immunohistochemical analysis showed markedly greater PSCA expression in superficial than invasive TCC. Notably, from a multivariate analysis, the expression level of PSCA was an independent predictor of disease recurrence in superficial TCC (P = 0.012).
  
  
  CONCLUSIONS
  These findings suggest that the PSCA expression level measured by real-time RT-PCR could be a valuable prognostic marker for tumour recurrence in superficial TCC of the bladder.
authors: Department of Urology, The University of Tokushima Graudate School Institute of Health Biosciences, Tokushima, Japan.
authors: Essam
authors: E
authors: Elsamman
authors: Tomoharu
authors: T
authors: Fukumori
authors: Toshinori
authors: T
authors: Kasai
authors: Hiroyoshi
authors: H
authors: Nakatsuji
authors: Masa-Aki
authors: MA
authors: Nishitani
authors: Kazunori
authors: K
authors: Toida
authors: Nermin
authors: N
authors: Ali
authors: Hiro-Omi
authors: HO
authors: Kanayama