Dihydropyrimidine dehydrogenase and the efficacy and toxicity of 5-fluorouracil

Eur J Cancer. 2004 May;40(7):939-50. doi: 10.1016/j.ejca.2003.12.004.


The identification of genetic factors associated with either responsiveness or resistance to 5-fluorouracil (5-FU) chemotherapy, as well as genetic factors predisposing patients to the development of severe 5-FU-associated toxicity, is increasingly being recognised as an important field of study. Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-fluorouracil (5-FU). Although the role of tumoral levels as a prognostic factor for clinical responsiviness has not been firmly established, there is ample evidence that a deficiency of DPD is associated with severe toxicity after the administration of 5-FU. Patients with a partial DPD deficiency have an increased risk of developing grade IV neutropenia. In addition, the onset of toxicity occurred twice as fast compared with patients with a normal DPD activity. To date, 39 different mutations and polymorphisms have been identified in DPYD. The IVS14+1G>A mutation proved to be the most common one and was detected in 24-28% of all patients suffering from severe 5-FU toxicity. Thus, a deficiency of DPD appears to be an important pharmacogenetic syndrome.

Publication types

  • Review

MeSH terms

  • Antimetabolites, Antineoplastic / adverse effects*
  • Antimetabolites, Antineoplastic / metabolism
  • Antimetabolites, Antineoplastic / therapeutic use
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / metabolism
  • Dihydropyrimidine Dehydrogenase Deficiency*
  • Dihydrouracil Dehydrogenase (NADP) / genetics
  • Fluorouracil / adverse effects*
  • Fluorouracil / metabolism
  • Fluorouracil / therapeutic use
  • Genotype
  • Humans
  • Mutation / genetics
  • Polymorphism, Genetic / genetics


  • Antimetabolites, Antineoplastic
  • Dihydrouracil Dehydrogenase (NADP)
  • Fluorouracil