Routine DPYD Genetic Testing

Abstract

In his article published in JCO, Dr Hertz 1 correctly pointed out that DPYD is a germline indicator of toxicity risk, yet fails to include many aspects of DPYD genetic testing in the clinic. Despite his title, he fails to address the main issues that actually influence the clinical logistics and realities of DPYD testing as a potential standard of care.

Reply to H.S. Hochster

“…I also agree with Dr Hochster 1 that practitioners will inevitably encounter patients with complete loss of DPD activity. However, I would argue that the dire consequences are not medicolegal for practitioners but rather severe toxicity and death for those patients who receive full-dose fluoropyrimidine treatment.…”

“…Dr Hochster 1 raises concerns about my recommending DPYD genetic testing before fluoropyrimidine treatment. 2 He points out that the proposed DPYD -guided dosing recommendations were not evaluated for efficacy in prospective randomized trials.…”

“…Dr Hochster 1 also mentions several logistical challenges of testing that were not the focus of my article. He suggests only approximately 2% of US patients carry a clinically actionable DPYD variant, on the basis of the original DPYD analysis in NCCTG N0147.…”