Cancer patients in clinical trials across the United States are undergoing a slew of expensive, invasive biopsies with no clear benefits, according to an analysis published Monday in the Journal of Clinical Oncology.
Patients involved in clinical trials for experimental drugs often get extra biopsies meant to search for biomarkers — broadly speaking, any type of biological measure of health or illness. The additional biopsies are often mandated by the National Cancer Institute or by the drug company sponsoring the trial, with a goal of using biomarkers to track how the medication affects patient health.
But when researchers looked at 72 clinical trials in which cancer patients had extra biopsies, they found that only 12 turned up any significant biomarkers. And none led to data on optimal drug doses for patients.
“It’s a little bit of a Wild West out there, and it shouldn’t be because it’s people’s tissues,” said Ruth Etzioni, a biostatistician with the Fred Hutchinson Cancer Research Center who was not affiliated with the study.
“We should be more respectful” of the patients, Etzioni said, adding that if “those trials weren’t properly designed or didn’t go anywhere with the tissue that they took, it was a waste.”
Dr. Mark Ratain, a coauthor of the study, said the average cost of the additional biopsies is about $6,675 per patient. All told, the studies he and his coauthors reviewed led to nearly 2,000 additional biopsies. He noted that biopsies are invasive and can be painful, as well as expensive.
“There’s a perception that these biopsies provide useful information. There’s a hope that you’ll learn something about the biomarkers, but often, you don’t,” said Ratain, an oncologist at the University of Chicago Medical Center.
The study authors argue that research institutions and funders should be more cautious in mandating nondiagnostic biopsies in clinical trials.
But the NCI, which funds many such studies, said there is a value to doing biomarker research from extra biopsies.
Whether or not a particular biomarker proves useful, most drug developers do try to develop them early on, said Dr. Jeffrey Abrams, associate director of the NCI’s cancer therapy evaluation program. “It provides the best way of trying to select the appropriate patient population, understand a drug’s mechanism of action, or monitor an agent for side effects or efficacy,” he said.