The significance of thymidine phosphorylase activity in hepatocellular carcinoma and chronic diseased livers: a special reference to liver fibrosis and multicentric tumor occurrence

The role of thymidine phosphorylase (TP), an angiogenic factor, in hepatoce llular carcinoma (HCC) remains unclear. The aim of this study was to clarif y the significance of TP in HCC. Thirty-seven patients with HCC, who underw ent hepatectomy, were included. The TP activity in both cancerous and non-c ancerous parts of livers were measured by an enzyme-linked immunosorbent as say. Another 11 patients without HCC were used to evaluate the TP activity in the non-cancerous parts of livers. Both the cancerous and non-cancerous TP activities were clinicopathologically investigated with special referenc e to the multicentric occurrence of HCCs and the degree of liver fibrosis; consisting of normal, fibrosis and cirrhosis. The TP activity in the cancer ous part was 94.6 +/- 70.2 U/mg protein, while that in non-cancerous parts of the liver was 80.9 +/- 48.8 U/mg protein. No significant difference was observed. The TP activity in the cancerous part did not correlate with any clinicopathological variables, such as tumor differentiation, portal vein i nvasion, intrahepatic metastases and prognosis. However, the TP activity in the non-cancerous parts of the liver correlated with the degree of fibrosi s (normal/fibrosis/cirrhosis = 34:74:90 U/ mg protein, respectively). Furth ermore, regarding the correlation between TP activity in the non-cancerous parts and the simultaneously multicentric occurrence of HCC, the TP activit y in the multicentric group (n = 8; 121 U/mg protein) was significantly hig her than that in the non-multicentric group (n = 29; 70 U/mg protein). The TP activity in the non-cancerous parts increased in proportion to the degre e of liver fibrosis. Furthermore, it is suggested that the higher TP activi ty in the noncancerous part is related to the multicentric occurrence of HC Cs. (C) 2009 Elsevier Science Ireland Ltd. All rights reserved.