[Review of pharmacokinetic monitoring of 5-Fluorouracil as a tool to increase efficacy and safety].

Recent progress in medical knowledge has indicated that both clinical and biological markers will determine the response to different medical treatments: age, gender and genetics will determine the success of treatment. Genetic variability in this respect is fundamental and determines efficiency and safety of drugs, as well as susceptibility and illness' development. Fortunately, personalized medicine now offers individually tailored treatment strategies for each patient's needs. This is of outmost importance in oncology, since treatment is per se toxic and the commonly found low serum drug concentrations result in low treatment efficacy. Personalized medicine will allow a better approach to this, until now, a poorly managed disease. In this review we intent to raise awareness of personalized medicine and of clinical pharmacologic monitoring, with the aim to achieve adequate levels of efficacy and safety in the use of the cytotoxic drug 5-Fluorouracil (5-FU). Additionally, the importance of pharmacogenomics for the use of 5-FU is discussed. We designed this discussion towards medical practitioners challenged with treatment decisions every day, together with their patients.