5-Fluorouracil (Adrucil, Carac, Efudex, Fluoroplex)

Description

5-Fluorouracil (5-FU) is a fluoropyrimidine antimetabolite chemotherapy agent that serves as a backbone treatment for colorectal cancer across multiple settings including adjuvant, neoadjuvant, and metastatic disease. It is commonly administered as part of combination regimens such as FOLFOX (5-FU, leucovorin, oxaliplatin) and FOLFIRI (5-FU, leucovorin, irinotecan) for both resectable and advanced colorectal cancer. The drug's efficacy can be influenced by microsatellite instability status and requires careful dosing considerations based on DPYD gene polymorphisms to prevent severe toxicity. 5-FU remains a cornerstone of colorectal cancer chemotherapy and is frequently combined with targeted agents like bevacizumab or cetuximab in metastatic settings.

Mechanism of Action

5-Fluorouracil acts as a pyrimidine analog that interferes with DNA and RNA synthesis through multiple pathways. The drug is converted intracellularly to active metabolites including 5-fluoro-dUMP, which irreversibly inhibits thymidylate synthase, blocking the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate and thereby preventing DNA synthesis. Additional metabolites incorporate into RNA, disrupting RNA processing and protein synthesis, ultimately leading to cell cycle arrest and apoptosis in rapidly dividing cancer cells.

Side Effects

Not all side effects are listed. Side effects vary by individual. Always consult your oncologist.

Clinical Trials