Why don't more people get genetic testing for cancer?

Genetic testing for cancer can bring more knowledge to patients and their relatives, but not enough people get it done

Credit: Michigan Medicine

Not enough people are getting genetic testing for cancer, according to recent research.

Germline genetic testing, in which inherited DNA is sequenced, is recommended for patients diagnosed with cancer to enable genetically targeted treatment and identify additional relatives who can benefit from personalized cancer screening and prevention. Guidelines recommend this testing for people with cancers including breast, ovarian, pancreatic, colorectal, prostate and others.

Despite the knowledge this could bring to patients and their relatives, researchers found that only 6.8% out of a million patients underwent the testing within two years of receiving a diagnosis. The testing rates were lowest among Black, Hispanic, and Asian patients.

“We were surprised at the low rates of testing given the growing evidence for the benefits of results for patients and their families,” said Steven Katz, M.D., M.P.H., Professor of Medicine and Health Management and Policy and leader of the Cancer Surveillance and Outcomes Research Team.

“Genetic testing is increasingly important in treatment decision-making after diagnosis of cancer,” said Katz. “Testing the right patients at the right time can better personalize the treatment plan to maximize outcomes. Testing patients can be the gateway to identify hereditary cancer risk in families and offer prevention and early detection strategies that can save lives.”

Testing has also become more accessible with the advancement of sequencing technology - the number of genes tested that are relevant to treatment and prevention has increased and costs for testing have declined.

“It’s not just about getting a test - it’s about integrating results into cancer management and prevention for patients and their families to save lives,” said Katz.

“We have shown that testing results often come too late to inform cancer management and too many patients with important test findings are left dangling on their own to communicate with their family about really complicated issues. We need to develop, deploy, and evaluate new strategies and tools to ensure that the rapid advances in genetic oncology are put into practice to improve health outcomes for patients and their families.”

Additional authors: Abrahamse, M.A., Allison Furgal, Ph.D., Rachel Tocco, Timothy P. Hofer, M.D., Steven J. Katz, M.D., M.P.H.

This research was supported by grant R01 CA225697 from the National Cancer Institute (NCI) (awarded to Stanford University) and grants P01 CA163233 and P30 CA046592 from the NCI (awarded to the University of Michigan). The collection of cancer incidence data in California was supported by the California Department of Public Health pursuant to California Health and Safety Code §103885 under cooperative agreement 5NU58DP006344 with the US Centers for Disease Control and Prevention (CDC) National Program of Cancer Registries, contract HHSN261201800032I with the NCI’s Surveillance, Epidemiology, and End Results (SEER) program (awarded to the University of California, San Francisco), contract HHSN261201800015I with the NCI’s SEER program (awarded to the University of Southern California), and contract HHSN261201800009I with the NCI’s SEER program (awarded to the Public Health Institute, Cancer Registry of Greater California). The collection of cancer incidence data in Georgia was supported by contract HHSN261201800003I and task order HHSN26100001 from the NCI and cooperative agreement 5NU58DP006352-03-00 from the CDC.

Paper cited: “Frequency of Germline Genetic Testing after Cancer Diagnosis,” ,Journal of American Medicine. DOI: 10.001/jama.2023.9526