Fluorouracil chemotherapy: The My5‑FU assay for guiding dose adjustment

The Committee recommended further research to validate the accuracy and precision of the My5‑FU assay for the quantitative determination of 5‑fluorouracil (5‑FU) at the lower end of its measuring range with analytical reference standard methods, including high‑performance liquid chromatography and liquid chromatography‑mass spectrometry. Studies should investigate the comparability of the methods and determine the clinical significance of discordant results with reference to their impact on subsequent dose adjustments.

The Committee recommended that robust evidence be generated to show the clinical effectiveness of pharmacokinetic dose adjustment of continuous infusion 5‑FU in people with colorectal cancer. Where possible, studies should consider the differential impact that pharmacokinetic dose adjustment may have on people with DPD (dihydropyrimidine dehydrogenase) deficiency, people with impaired renal or liver function, people whose body surface area is outside the standard range for dosing 5‑FU and people with a less favourable performance status. Future studies might also consider the impact of DPD testing in conjunction with pharmacokinetic dose adjustment.

The Committee recommended further research to establish optimal target dose ranges for 5‑FU plasma levels in people with head and neck cancer, stomach cancer and pancreatic cancer. Future studies should aim to both establish the optimal target dose range for each cancer and quantify its impact on clinical outcomes, taking into account any variation that may occur between different continuous infusion 5‑FU regimens.

The Committee recommended further research to explore the impact of having continuous infusion 5‑FU on patients. Future studies should investigate the experiences of patients having continuous infusion 5‑FU and take into account the impact on quality of life. The potential consequences of introducing pharmacokinetic dose adjustment should also be explored.