Lung-MAP Trial Reveals Genetic Testing Knowledge Gaps Among Patients

Precision medicine has helped personalize treatment for certain patients with cancer. Advances in the understanding of individual genetics allow health care professionals to tailor therapy to a particular type of tumor. Although precision medicine may spare patients from treatments that don’t work, not all patients understand the importance of tumor genomic test results, according to preliminary study findings presented during the World Conference on Lung Cancer in Barcelona, Spain.

Researchers with the Lung Cancer Master Cancer Protocol (Lung-MAP) study uncovered this gap in knowledge after surveying 123 patients over the phone from February 2018 to April 2019. They asked 38 questions adapted from prior cancer genomic results studies to test patient knowledge of genomic testing. Patients were mostly men (61%) and white (95.1%), and the mean age was 67.8 years.

“We are trying to match drugs to genetic changes in the body,” Joshua A. Roth, a Lung-MAP investigator and an assistant member of the Hutchinson Institute for Cancer Outcomes Research at the Fred Hutchinson Cancer Research Center, said in an interview with CURE®.

“We know that with certain changes, certain drugs are more effective. They can, for example, help you live longer. The idea is to try to find these pairs, but the challenge in doing that is that often, the percentage of patients with these genetic changes are small, and so using a traditional approach would take many, many clinical trials to find all the right matches between drugs and genetic changes. That’s what led to this biomarker clinical trial that Lung-MAP is a part of.”

The researchers found that nearly 90% of respondents knew that their test results would be used to select their cancer treatment. Another 82.9% said they received enough information about their tests to understand the benefits of enrolling in the trial, and 73.2% reported that they had enough information to understand the study risks.

However, gaps existed in the understanding of genomics’ role in risk of other diseases or cancer risk in family members. Participants had received testing that detects DNA mutations in cancer cells known as somatic mutations — meaning these are in tumor cells, but not normal cells and therefore not passed down to subsequent generations. Although some precision medicine clinical trials include germline testing, which detects inherited DNA mutations, this study did not.

The survey asked about both somatic and germline testing. Researchers reported that just 9% of patients knew that the somatic testing could not predict if a family member was at increased risk of getting cancer, and 12% knew their results couldn’t predict their own increased risk of other diseases.

“The distinction between germline and somatic mutations would come from a one-on-one discussion with a study physician or study staff,” Roth, who holds a doctorate in pharmaceutical outcomes research and policy, said. “We don’t know on an individual basis what they heard or didn’t hear, but we do know now that there are knowledge gaps. So there is a need to come up with more systematic ways to explain this stuff to make sure all patients have a baseline sense of what is happening and what isn’t happening.”

Patients who don’t understand the difference between the tests or any other information on the clinical trial consent form should speak with a trial investigator or find support through a genetic counselor, Roth said.

Next steps include an analysis follow- up with all 207 patients — 84 were enrolled after April 2019 — with the hope of developing interventions, such as screening for misunderstanding or inserting more information into the clinical trial consent form.

“This speaks to understanding the benefits and risks of trials and the ability to give informed consent to participate,” Roth said. “We don’t want to have misunderstandings about these issues where a patient might think they are getting more information than they really are. We want them to come in with appropriate expectations.”

Lung-MAP is the first major National Cancer Institute trial to test multiple treatments at the same time. Enrolled patients get a genomic profile to determine the genomic alterations, or mutations, that may drive the growth of their cancer and are treated based on the results. Earlier this year, the trial expanded enrollment to include patients with all types of non-small cell lung cancer rather than just those with advanced-stage squamous cell lung cancer.