5-fluorouracil therapeutic drug monitoring and adverse events in a Romanian population

Fluoropyrimidines represent the backbone of many chemotherapy protocols and the standard treatment for many types of tumors. Toxicity associated with fluoropyrimidines can occur in up to 40% of cases. BACKGROUND AND PURPOSE: The objective of this study was to analyze the correlation between the plasma concentration of 5-fluorouracil and the adverse events that patients might experience during this therapy. METHODS: A total of 58 patients received 5-fluorouracil-based chemotherapy. A blood sample was collected from each patient during the drug infusion, in order to assess the area under the curve for 5-fluorouracil. The occurring adverse events were evaluated through medical recordings of the patients’ reported symptoms, clinical and paraclinical examinations. RESULTS: In our study, the majority of patients experienced some type of toxicity. Moreover, we found a correlation between 5-FU plasma concentration (expressed as AUC) and adverse events, a stronger one with hematological adverse reactions and a weaker one with gastrointestinal and cardiovascular toxicity. CONCLUSION: Determining the plasma concentration of 5-FU in patients with severe toxicities could represent a method of individualizing the treatment and improving the safety profile.