Individualization of chemotherapy regimens including 5-fluorouracil in patients with colorectal cancer and head and neck cancer: theoretical and practical aspects

Abstract

5-fluorouracil (5-FU) is a fluoropyrimidine used in oncology since the late 1950s. Numerous observations indicate that the currently used method of calculating the dosage of this drug based on body surface area (BSA) does not allow for achieving its optimum concentrations ensuring maximum efficiency at the least possible toxicity. 5-FU concentrations in plasma at the same dose calculated on the basis of BSA can vary over 10-fold. Pharmacokinetic parameters best associated with the biological effects of treatment with 5-FU is the total drug exposure or the area under the curve (AUC) of its concentration. The development of methods enabling fast and simple measurement of 5-FU concentrations in plasma and AUC assessment allows currently for dose individualization of this compound.