Clinicopathological significance of pyrimidine nucleoside phosphorylase (PyNPase) and dihydropyrimidine dehydrogenase (DPD) in advanced colorectal cancer

: We examined clinicopathological characteristics and prognoses of seventy advanced colorectal cancer cases by measuring pyrimidine nucleoside phosphorylase (PyNPase) and dihydropyrimidine dehydrogenase (DPD) in tumor and normal tissue. PyNPase activities in cancerous tissue obtained from resected were 82.7 +/- 41.9 U/mg protein, which were significantly higher than 37.2 +/- 24.0 U/mg protein in normal tissue (p < 0.001). On the other hand, DPD activities in cancerous tissue were significantly lower in normal tissue (p < 0.05). In cases with lymphnode metastases, PyNPase activities of cancerous tissue were significantly higher than that of no lymphnode metastases cases (p < 0.05). In cases with grade 2 side-effects or higher by oral adjuvant chemotherapy, DPD activities in normal tissue were significantly lower than that of other cases (p < 0.05). With regard to Dukes' B and C cases that were resected curatively, PyNPase activities of cancerous tissue of higher group's prognosis were worse than that of the lower group. In the group received 5'-DFUR as adjuvant chemotherapy, non-recurrent survival rate of the group exhibiting higher PyNPase activities was better than that of the lower group.