Expression of thymidine phosphorylase in primary human renal cell carcinoma by ELISA method

Thymidine phosphorylase (TP) expression in 100 paired samples of renal cell carcinoma (RCC) and normal adjacent tissue was analyzed by an ELISA method. We also investigated whether TP expression correlates with clinicopathological findings and clinical outcomes of these patients. Median TP expression was 9-fold (range, 0.5-56) higher in primary tumor than in non-cancerous renal tissue (P < 0.0001). There was a significant difference with respect to tumor venous invasion. TP expression was significantly higher in patients with such venous invasion than in those without (P = 0.018). However, there was no correlation between TP level and other clinicopathological findings and the survival curves. These results suggest that ELISA is useful for evaluating TP expression of human RCC and may provide a novel approach to therapy for patients with RCC.