Clinical studies of intrarectal administration of 5-FU emulsion as an adjunct to surgical treatment of rectal cancer.

Preoperative intrarectal administration of 5-FU emulsion was attempted as an adjuvant chemotherapy to surgery for rectal cancer. The drug concentrations of resected specimens were determined and histological examinations of them were carried out in order to evaluate the effect of anticancer drugs on the metastatic lymph nodes as well as on the primary tumors. 5-FU levels both in the regional lymph nodes and primary tumors of 18 patients with rectal cancer, who were given with the 5-FU emulsion (emulsion group) or 5-FU suppository (suppository group) intrarectally two hours before surgery, was found to be much higher in emulsion group than in suppository group. 46 patients with rectal cancer were treated preoperatively with intrarectal administration of 5-FU emulsion (25 cases) or 5-FU suppositories (21 cases) for a period of 10 days before surgery, and the histological effect of this regimen on the metastatic lesion in the lymph nodes, as well as in the primary tumor was examined. No detectable difference was found in the primary lesions between the emulsion group and the suppository group. In the metastatic lesions, however, the rate of effectiveness was higher in the emulsion group than in the suppository (68 percent versus 33 percent).