A new clinical study, launched by The Alliance for Clinical Trials in Oncology, will look at how to best communicate information about genetic risk to family members of people with colorectal cancer, with the hope that the results will increase genetic testing among these families.
“Sharing genetic information can be stressful and confusing, especially right after a cancer diagnosis,” said Frank Sinicrope, MD, study co-chair and a gastroenterologist at the Mayo Clinic in Rochester, Minnesota. “Some patients aren’t sure how to explain test results, while others worry about upsetting loved ones. This study hopes to identify a clear, helpful approach that makes it easier for families to understand their risks and take preventive action.”
Supported by grants from the National Cancer Institute, the “Family Communications After Genetic Testing” trial plans to enroll around 4000 people with colorectal cancer and their at-risk relatives across multiple sites within the U.S. National Clinical Trials Network and National Cancer Institute Community Oncology Research Program.
At present, patients are asked to communicate their abnormal genetic test results to their family members, and the uptake of genetic testing is low.
“In a study done at Mayo Clinic and despite the offer of free genetic testing to relatives of cancer patients found to have a high-risk germline variant, only 18% of family members actually underwent genetic testing,” Sinicrope told Inside Precision Medicine.
“Many people don’t realize that colorectal cancer can run in families,” said Heather Hampel, CGC, study co-chair and a genetic researcher with the City of Hope cancer center in Duarte, California. “In fact, about 30% of colorectal cancer cases are linked to genetics, and around 15% of newly diagnosed patients have a gene change that increases cancer risk.”
The study group will investigate whether changing the way genetic information is communicated to family members will increase genetic testing.
“We will determine whether a provider-mediated approach with direct communication of genetic test results to family members by the study team results in increased rates of genetic testing of family members compared with the standard approach where patients inform their own family members,” said Sinicrope.
“As a secondary objective, we will also look at rates of cancer prevention testing such as colonoscopy to see if we are influencing rates of such testing.”
The trial will be open to patients with newly diagnosed stage I to IV colorectal cancer who will all undergo testing with a comprehensive multi-gene hereditary cancer panel available from LabCorp.
The researchers plan to compare the proportion of first-degree relatives who undergo genetic testing after being given information by the study team with the proportion who take up testing after receiving the information by a family member.
The two groups will be divided into patients who have Lynch Syndrome, a genetic syndrome that is inherited by 50% of first-degree relatives and is associated with an increased risk for colorectal and other cancers, and those who do not.
The investigators will also look at how race/ethnicity, sex, age, tumor location, tumor stage, geographic location (urban vs. rural), and the type of medical facility (academic vs. community) impact the uptake of genetic testing and preference for provider-mediated or patient-mediated communication.
The scale and complexity of the study mean that it will be at least four years before results are available, but Sinicrope hopes that its ultimate impact will be to “increase genetic testing of relatives of patients with hereditary predisposition to cancer and thereby prevent cancers from developing in relatives.”
