A new meta-analysis led by Joseph Unger, PhD, of Fred Hutchinson Cancer Research Center has revealed that structural and clinical barriers prevent more than 3 out of 4 cancer patients from participating in clinical trials.

The study is part of an ongoing effort to understand why patient participation is so low in cancer clinical trials. Unger, a health services researcher and biostatistician who focuses on disparities in cancer research, published his findings today in JNCI, the Journal of the National Cancer Institute.

“From the beginning of a patient’s cancer evaluation, from the moment they walk into the clinic, there are multiple barriers to participating in a clinical trial,” he explained. “It turns out structural barriers alone — the fact that there’s just not a trial available — represent the reason why more than half of patients don’t go on trials.”

Unger and colleagues from Columbia University Irving Medical Center, and the American Cancer Society Cancer Action Network (ACS CAN) used 13 studies with nearly 9,000 cancer patients (nine in academic research settings and four in community settings) for their analysis. More than half of the patients (55.6 percent) did not participate in a trial because no trial was available for their type and/or stage of cancer at their treatment center. An additional 21.5 percent of the patients were ineligible for whatever trials were available due to clinical barriers like criteria that excludes patients with additional health issues, known as comorbidities. Physician- and patient-related barriers, such as not being asked to participate or refusing to participate, made up the remaining 22.9 percent.

“Patients are actually quite willing to participate in trials if they’re offered one,” Unger said. “But big structural barriers and clinical barriers get in the way. Having to travel to participate in a trial can be an overwhelming burden to patients. And there’s been criticism that the eligibility criteria may be too narrow.”

Multiple cancer organizations are recommending the modernization of eligibility criteria for trials.

Unger and colleagues from the SWOG Cancer Research Network recently modeled what more relaxed criteria might mean. Loosening restrictions regarding individuals with liver, kidney and cardiovascular disease as well as prior cancers could allow more than 6,300 additional patients to participate in a trial.

“There’s a lot of emphasis on patient barriers and why patients don’t go on trials,” Unger said. “The implication, unintentionally, is that somehow it’s all the patients’ fault. But it’s not. What’s overlooked are the structural and clinical barriers to trial participation.”

This study was funded by the National Cancer Institute. “Systematic Review and Meta-Analysis of the Magnitude of Structural, Clinical, and Physician/Patient Barriers to Cancer Clinical Trial Participation,” published February 19, 2019, by the Journal of the National Cancer Institute.

This article was originally published on February 19, 2019, by Hutch News. It is republished with permission.