Fluoropyrimidines, after more than 50 years of their discovery, are still the treatment of many types of cancer, and annually is estimated that two million patients use fluoropyrimidine treatment. The toxicity associated with fluoropyrimidines affects 30-40% of patients and some adverse effects can be lethal.

Dihydroypyrimidine dehydrogenase is the main enzyme in the catabolism of 5-FU and DPD activity deficiency can cause important toxicity. There is an important reason for determinate DPD activity in order to improve patient safety and to limit potential life-threating toxicity.

Now, are available multiple phenotypic and genotypic methods to determinate DPD activity, some of this methods have proven their usefulness in practice, but yet there are not routinely recommended in clinical practice.

This review is another statement of the importance of determination DPD status, the phenotypic and genotypic methods that are available and can be used.


chemotherapy, fluoropyrimidine treatment, toxicity