The Role of 5-Fluorouracil in Malignant Disease

Abstract

Because the pyrimidine 5-fluorouracil interferes with the formation or utilization of thy mine, a clinical trial of its antineoplastic properties was undertaken. 5-Fluorouracil was administered to 118 patients. Definite objective improvement occurred in 31 patients. However, only 18 of the objective regressions were of greater than 2 months duration. Of these 18, 12 patients (10%) maintained objective regres-sions more than 6 months. 5-FU was most effective in breast cancer; improvements also occurred in cancer of the ovary and in an undif-ferentiated carcinoma. Objective improvements in colon cancers were not observed. The objective responses noted followed administration of a maximal or sub-lethal dose of 5-FU and were usually associated with severe toxicity. Consistent toxic reactions from 5-fluorouracil consisted of nausea or vomiting, stomatitis, diarrhea, leukopenia, fever and alopecia. A mortality rate of 6% was recorded as a result of therapy. The high degree of toxicity of 5-FU therapy has resulted in increased morbidity. Patients not demonstrating improvement became more rapidly debilitated as a result of the drug toxicity and survival time was decreased.