Attitudes and engagement about cascade genetic testing in a population-based cohort of women diagnosed with cancer.

Steven Jay Katz University of Michigan, Ann Arbor, MI info_outline Steven Jay Katz, Kevin C Ward, Ann S. Hamilton, Paul Abrahamse, Rachel Hodan, Allison W. Kurian, Lauren P. Wallner, Sarah T. Hawley

Authors Steven Jay Katz University of Michigan, Ann Arbor, MI info_outline Steven Jay Katz, Kevin C Ward, Ann S. Hamilton, Paul Abrahamse, Rachel Hodan, Allison W. Kurian, Lauren P. Wallner, Sarah T. Hawley Organizations University of Michigan, Ann Arbor, MI, Emory University, Atlanta, GA, University of Southern California, Los Angeles, CA, Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, Stanford University, Stanford, CA, Michigan Medicine, Ann Arbor, MI Abstract Disclosures Research Funding National Cancer Institute American Cancer Society Background: Cascade testing in families with hereditary cancer syndromes is challenging because patients are responsible for engaging their relatives about test results and clinical support is limited. There are concerns that patient engagement with relatives may not be well matched to the clinical relevance of their test results, with particular concern about variants of uncertain significance (VUS). Methods: We selected patients from the Georgia California Genetic Linkage Initiative, which identified all patients diagnosed with cancer 2013-19 in the 2 states who linked to a germline genetic test. We surveyed 2100 women diagnosed with breast, ovarian or uterine cancer in 2018-19 in Georgia and California who reported "a pathogenic variant (PV) that increases the risk of cancer" on testing about 4 years after diagnosis. We also surveyed a comparable sample of 1300 women diagnosed during the same period who reported a VUS-only result. The expected response rate from the cohorts is 55% (N=1900). We present preliminary results on patient attitudes about cascade family testing and report of engagement with genetic counselors and relatives about test results. Results: The 2 cohorts were comparable in age (mean 54 vs 58 for VUS, p<.001) and education (college graduate or more 52% vs 53% for VUS p=.971). The Table shows that for patients who reported a PV, belief in the utility of testing in relatives (test results useful for family; wanted family members tested) was high. A substantial proportion reported that a genetic counselor encouraged them to talk to relatives and talked directly with relatives about testing. PV carriers informed most first-degree relatives about their test results. Patients who reported VUS only were less likely to endorse the utility of testing in relatives; less likely to report that a genetic counselor encouraged family engagement or engaged family directly about testing; and were less likely to have informed relatives about their test results. Conclusions: Compared to patients with VUS-only test results, women with PVs on germline genetic testing after diagnosis of cancer had more positive attitudes about the utility of testing of family members and greater engagement with clinicians and family members about test results. These findings suggest that engagement with family about genetic testing after cancer diagnosis matches the clinical relevance of the results. Patient attitudes and report of engagement about genetic test results. % Item PV N=598 VUS only N=297 Understand my genetic test results well enough to inform relatives 75 60 Believe genetic test results are useful to my family 90 64 Wanted family members to get tested 84 46 Genetic counselor encouraged me to talk about results with family 73 46 Genetic counselor talked directly with family members about testing 56 38 % of first-degree relatives who were informed of patient test results, mean 88 65 All comparisons p<.001.