TRENTON, N.J. – Cancer patients with an underlying genetic mutation may experience severe side effects taking certain anticancer drugs. One assemblyman wants patients and their doctors to rule out that mutation before starting treatment.
Christopher P. DePhillips is sponsoring a bill that would require physicians to offer cancer patients screenings for DPD deficiency prior to chemotherapy with fluoropyrimidines. The bill (A986) would also require insurance plans to cover that testing well as prescription drug treatment.
“There’s debate among doctors whether patients in general should be tested for the deficiency. I believe the chance of adverse effects is great enough that patients should be tested,” DePhillips said. “While all medical treatments pose some risk, physicians and their patients should have confidence that the cure isn’t worse than the disease.”
DPD, which is shorthand for dihydropyrimidine dehydrogenase, is an enzyme that breaks down thymine and uracil, two DNA building blocks. Those with a deficiency cannot break those down. And while fluoropyrimidines are widely used to treat solid cancers—pancreas and gastric, head and neck, breast, and colorectal—those with the deficiency cannot metabolize those drugs, leading to severe toxicity, and in some cases, death. Medical literature suggests 2% to 8% of the general population may have total or partial DPD deficiency.
Severe deficiency is rare and appears in infants. Those children may experience seizures, microcephaly, and motor skills delays. Adults with the deficiency appear asymptomatic, hence the importance of testing before treatment.
“Anyone seeking treatment for cancer should know they are healthy enough to tolerate chemotherapy,” DePhillips said. “This bill ensures anyone who wants to be tested for DPD deficiency will be tested and, if necessary, treated.”
The bill was inspired by the plight of Kerrie Prettitore, a Ridgewood mother of three who was treated for colon cancer in 2014. While the surgery proved successful, her first chemotherapy treatment left her severely ill in intensive care. Doctors didn’t test her for the deficiency until three weeks after her toxic reaction to a fluoropyrimidine. Although an experimental antidote was eventually administered, Kerrie never completely recovered from the overdose and died in 2018. Her husband, Glenn, has since petitioned the government to require doctors to test for the deficiency.
Fluoropyrimidines are a class of anti-cancer drugs such as Tegafur, Fluorouracil, Doxifluridine, Carmofur and Capecitabine.
The bill unanimously passed the Assembly Health Committee for full assembly consideration.