[Clinical significance of determinations of dihydropyrimidine dehydrogenase levels in primary and hepatic lesions of colorectal cancer patients].

ABSTRACT

Dihydropyrimidine dehydrogenase (DPD) levels were determined by enzyme-linked immunosorbent assay in primary tumors and adjacent normal mucosa from 114 colorectal cancer patients, including 9 with synchronous liver metastases. The level of intratumoral DPD was 55.0 +/- 38.7 unit/mg protein (n = 114) and that of mucosal DPD was 55.0 +/- 38.7 unit/mg protein (n = 114). The ratio of intratumoral DPD to mucosal DPD was 1.8 +/- 0.8 in patients developing metachronous liver metastases (n = 7), 1.0 +/- 0.5 in patients without recurrence (n = 61), and 1.0 +/- 1.1 in patients with synchronous liver metastases (n = 31) (p = 0.01, metachronous liver metastasis group versus recurrence-free and synchronous liver metastasis groups). The levels of DPD were higher in primary lesions than in synchronous liver metastasis (n = 9, p < 0.05). These results indicate that (1) degradation of 5-fluorouracil (5-FU) is enhanced in hepatic lesions more than in primary lesions, which is consistent with previous findings showing the therapeutic advantage of hepatic arterial infusion over intravenous infusion in relation to the treatment of 5-FU for liver metastases of colorectal cancer patients; and (2) predicting the effectiveness of hepatic arterial infusion of 5-FU for patients with metachronous liver metastases is difficult based on DPD determination of primary lesions alone.