Work

Thymidylate Synthase (TYMS) and Methylenetetrahydrofolate Reductase (MTHFR) Gene Polymorphisms Associated With Severe Capecitabine Toxicity: The First Case From Saudi Arabia

Year: 2023

Type: article

Abstract: Dihydropyrimidine dehydrogenase (DPD) is the major enzyme in the catabolism of fluoropyrimidine chemotherapy. Deficiencies in this enzyme level typically predispose patients to fluoropyrimidine toxicities, and they are often linked to DPYD gene polymorphisms. Other gene polymorphisms such as thymidylate synthase (TYMS) and methylenetetrahydrofolate reductase (MTHFR) may induce similar toxicities. We report a patient with resected stage III colon cancer presenting with severe toxicity to adjuvant capecitabine, a prodrug of 5-fluorouracil (5-FU). Her DPYD gene sequencing was normal. However, the patient was heterozygous for c.1298A>C (p.E429A) in the methylenetetrahydrofolate reductase (MTHFR) gene and c.*450_*455del in the thymidylate synthase (TYMS) gene. The capecitabine dose was reduced in subsequent treatments and then titrated up gradually with no major side effects reported.

Source: Cureus

DOI: 10.7759/cureus.49215

Authors: Nedal Bukhari, Hani Al-Mohanna, Fahad Almsned

Institutions: Riyadh Armed Forces Hospital, King Fahad Specialist Hospital, Imam Abdulrahman Bin Faisal University

Language: English

Topic: Pharmacogenetics and Drug Metabolism

Subfield: Pharmacology

Field: Pharmacology, Toxicology and Pharmaceutics

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: diamond

OpenAlex ID: W4388907451