Fluorouracil (5-FU)

Fluorouracil, known as 5-FU, is a chemotherapy drug that interferes with cancer cells' ability to make DNA and RNA, blocking their growth. It is given by injection or continuous IV infusion and is most commonly used for gastrointestinal, breast, and head-and-neck cancers. It is not a standard first-line drug for mesothelioma, though it has been studied in some combination regimens.

Origin

5-FU was synthesized in 1957 by Charles Heidelberger and colleagues at the University of Wisconsin, who reasoned that tumor cells absorb uracil faster than normal cells. Substituting a fluorine atom at the 5-position of uracil produced a molecule that the cancer cell takes up but cannot use, disrupting DNA synthesis. It became one of the earliest rationally designed chemotherapy drugs.

Significance in Asbestos Context

For most patients with mesothelioma, the standard chemotherapy backbone is pemetrexed combined with cisplatin or carboplatin, not 5-FU. Fluorouracil may appear in a treatment plan if a patient has a second cancer (such as a gastrointestinal tumor), if first-line mesothelioma therapy has failed, or as part of a clinical trial. Patients should ask their oncologist specifically why 5-FU is being recommended over standard regimens and whether the choice reflects a coexisting cancer, a research protocol, or a salvage strategy.

Example Sentence

"Because the patient had both peritoneal mesothelioma and a separate colon cancer, the oncologist designed a regimen that included 5-FU alongside the mesothelioma-directed therapy."

Related Terms

Chemotherapy, Pemetrexed, Cisplatin, Carboplatin, Mesothelioma, Clinical Trial

Notes

• Ask your oncologist to explain in writing why 5-FU is being chosen over the standard pemetrexed-platinum regimen for mesothelioma, and keep that explanation with your medical records.
• Patients should be tested for DPD (dihydropyrimidine dehydrogenase) deficiency before starting 5-FU; a deficiency can cause severe, life-threatening toxicity and is a question worth raising directly with the prescribing physician.
• Watch for and report mouth sores, severe diarrhea, chest pain (5-FU can cause coronary artery spasm), and hand-foot syndrome. These aren't minor side effects and may require dose adjustment or stopping the drug.
• Keep copies of all chemotherapy records, including drug names, doses, and dates of administration; these documents matter for both ongoing medical care and for any legal claim documenting the cost and burden of treatment.