Prognostic significance of thymidine phosphorylase in superficial bladder carcinoma.

Objective: We investigated the expression of thymidine phosphorylase (TP) in bladder carcinomas and assessed its prognostic significance in superficial bladder cancer samples. Patients and methods: We studied 142 primary bladder cancer samples immunohistochemically for nuclear thymidine phosphorylase (TPN), cytoplasmic (TPC) and stromal (TPSTR) expression. We correlated them with standard clinicopathological features (grade, stage, concurrent in situ, multiplicity, primary or recurrent status), as well with recurrence and progression. We examined also the relationship between TP and tumor microvessel density. Results: The level of all types of TP correlated well with stage, while grade correlated well only with TPSTR and the presence of carcinoma in situ only with TPN. Patients with low levels of TPN had a longer tumor free interval, during a 38.6 months mean follow up time. Regarding the association between TP count and microvessel density we found the strongest association with TPSTR (p=0.003), a borderline statistical significance with TPC (p=0.049) and no relationship with TPN (p=0.072). Conclusions: We suggest that the assessment of TPN might be useful for predicting recurrence in superficial bladder cancer. We propose also that TP may stimulate angiogenesis.