Overdosing on chemo: A common gene test could save hundreds of lives each year

Most importantly, he said, patients must be aware of the risk. “You tell them, ‘I am going to give you a drug with a 1 in 1,000 chance of killing you. You can take this test. Most patients would be, ‘I want to get that test and I’ll pay for it,’ or they’d just say, ‘Cut the dose in half.’”

Alan Venook, the University of California-San Francisco oncologist who co-chairs the National Comprehensive Cancer Network, has led resistance to mandatory testing because the answers provided by the test, in his view, are often murky and could lead to undertreatment.

“If one patient is not cured, then you giveth and you taketh away,” he said. “Maybe you took it away by not giving adequate treatment.”

Instead of testing and potentially cutting a first dose of curative therapy, “I err on the latter, acknowledging they will get sick,” he said. About 25 years ago, one of his patients died of 5-FU toxicity and “I regret that dearly,” he said. “But unhelpful information may lead us in the wrong direction.”

In September, seven months after his brother’s death, Kapoor was boarding a cruise ship on the Tyrrhenian Sea near Rome when he happened to meet a woman whose husband, Atlanta municipal judge Gary Markwell, had died the year before after taking a single 5-FU dose at age 77.

“I was like … that’s exactly what happened to my brother.”

Murray senses momentum toward mandatory testing. In 2022, the Oregon Health & Science University paid $1 million to settle a suit after an overdose death.

“What’s going to break that barrier is the lawsuits, and the big institutions like Dana-Farber who are implementing programs and seeing them succeed,” she said. “I think providers are going to feel kind of bullied into a corner. They’re going to continue to hear from families and they are going to have to do something about it.”