Prognostic significance of platelet-derived endothelial cell growth factor/thymidine phosphorylase expression in stage pT1 G3 bladder cancer

Background: The management of patients with pT1 G3 bladder cancer remains controversial because of the high incidence of recurrence with muscle invasion. Thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF) and has angiogenic activity. The aim of this study was to determine whether the expression of PDECGF/dThdPase in bladder cancer tissue was associated with tumor progression and recurrence in patients with pT1 G3 bladder cancer. Methods: Fifteen patients who were pathologically diagnosed as having pT1 G3 transitional cell carcinoma of the bladder were treated with transurethral resection. Sections of paraffin-embedded bladder tissue were immunohistochemically stained with either mAb654-1, a monoclonal antibody against human PD-ECGF or anti-CD34 monoclonal antibody, respectively. When more than 10% of tumor cells were positively stained with mAb654-1, this section was defined as positive in this study. Results: Eight of 15 sections from patients with pT1 G3 bladder cancer (53%) were positive with PD-ECGF/dThdPase. During follow up, patients in the negative group had no disease progression and only two patients had local recurrence. In contrast, seven of eight positives had recurrence (P< 0.05) and progression was also observed in four recurrent patients. However, there was no statistical relationship between PD-ECGF and CD34 expression in any of the patients. Conclusion: The expression of PD-ECGF/dThdPase appears to be an important prognostic factor of pT1 G3 bladder cancer and did not show any significant relationship between PD-ECGF/dThdPase expression and vascular density.