[Pharmacological study of 5'-DFUR oral administration and the clinical responses against gastrointestinal carcinoma].

In 4 out of 5 patients given 400 mg orally 5'-DFUR before surgery, intratumor 5-FU concentration showed over 150 ng/g. The concentration of either 5-FU or 5'-DFUR in the portal and peripheral blood of these patients exceeded the limits of assay. 5-FU concentration in peripheral blood was less than 0.05 micrograms/ml. White blood cell and platelet counts in the patients given 1,600 mg/day (no administration for 2 days/week) of 5'-DFUR for one month were essentially the same with those at the time of start of the treatment. Two of three patients showed minor response following the treatment with 5'-DFUR. Thus, administration of 1,600 mg/day of 5'-DFUR may be considered as an effective treatment of fluopyrimidine against advanced cancer. For the prediction of gastrointestinal side effect, assay of the 5-FU concentration in the portal blood seemed to be useful.