[Evaluation of pre-operative 5-fluorouracil treatment of the patients with gastric cancer--alteration of the inhibition rate of thymidilate synthetase by dose difference].

5-fluorouracil (5-FU) was orally administered before surgical operation to two groups of patients, one treated at 300 mg for 7 days and the other treated at 400 mg for 5 days, to examine the change of TSIR in gastric patients. Tumor tissue, lymph node and normal lesions were collected from removed specimens immediately frozen. As a result, there were no differences in FdUMP volumes of various tissues between 300 mg and 400 mg groups. TSIR tended to be higher in the order of normal tissue, lymph node and tumor lesions. TSIR was significantly higher in 400 mg group than 300 mg group. We believe that further studies on TSIR will provide a useful information as to various studies, including efficacy reinforcement by combination therapy, problems in resistance, histological efficacy and sensitivity tests.