Reply to: "Is uracil enough for effective pre-emptive DPD testing?".

This document is a reply to a letter discussing the effectiveness of uracil for pre-emptive DPD testing. The authors acknowledge the limitations of their study, including the omission of testing for haplotype B3 and the lack of information on renal and liver functions. They disagree with the assumption that a non-detectable UH2 is necessary for a true DPD deficient status. The authors suggest that a combination of indirect phenotyping and extended genotyping may improve the identification of patients at risk for severe fluoropyrimidine toxicity. [Extracted from the article]