DOSE INDIVIDUALIZATION IN CANCER-CHEMOTHERAPY - PHARMACOKINETIC AND PHARMACODYNAMIC RELATIONSHIPS

Dosages of anticancer agents are usually calculated with a uniform sta ndard, the body surface area (BSA). Although the BSA is proportionate to many physiological functions, it is, however, only partially relate d to the overall drug clearance. Consequently, a wide variability in d rug-exposure and drug-concentrations can be found between patients, by which some experience little toxicity, while others may show severe t oxic symptoms. In those cases demonstrating clear pharmacokinetic/phar macodynamic correlations the use of these relationships may aid to opt imize and to individualize chemotherapy. This manuscript overviews the relationships between pharmacokinetic parameters and their pharmacody namic outcome as reported in the literature. It is concluded that in c ertain cases monitoring of plasma drug concentrations can, indeed, be a useful tool to further optimize the current cancer chemotherapy. Esp ecially for anticancer agents that display a high interpatient pharmac okinetic and pharmacodynamic variability it may be beneficial to monit or plasma drug concentrations. A prerequisite is, however, that there is a clear correlation between a pharmacokinetic parameter and clinica l outcome.