Heterogeneity and clinical role of thymidine phosphorylase activity in gastric cancer

We examined the dThdPase activity in primary gastric cancer and metastatic lymph nodes from human subjects. The dThdPase activities were significantly higher in primary tumors than in the normal gastric wall, particularly in the center of the tumor rather than in the periphery (P<0.01). Tumors with a high dThdPase activity often had venous invasion (P<0.01). The dThdPase activities were significantly higher in metastatic lymph nodes than in the nodes without metastasis (P<0.01). The intratumoral heterogeneity of dThdPase activity was identified and cancer cells with high dThdPase activity may indicate that metastasis will likely occur.