Genetic testing may be beneficial post-cancer diagnosis for reducing cancer risk for families with hereditary cancer syndromes and managing treatment.
Investigators found that female patients with breast cancer, across racial and ethnic subgroups, did not receive genetic counseling or testing, despite being eligible, according to results of the iCanCare study published in the Journal of Clinical Oncology.1
Those who were eligible and did undergo genetic counseling and/or testing discussed their results with family, which investigators noted may be beneficial post-cancer diagnosis for reducing cancer risk for families with hereditary cancer syndromes and treatment management.
Results showed that 47.4% of the female breast cancer survivors surveyed had indications for genetic testing, including 28.0% at the baseline of 7 months after diagnosis and 19.4% at the time of follow-up. Genetic testing was reported for 71.9% (95% CI, 67.4%-76.4%), 53.3% (95% CI, 47.3%-59.2%), and 35.0% (95% CI, 31.6%-38.4%) of those with baseline indication, follow-up indication, and no indication, respectively (P < .001). Results were similar across racial and ethic groups (P = .239).
Testers reporting a pathologic event (n = 62) discussed genetic testing to most or all of their first-degree adult relatives 62.7% of the time. By contrast, survivors reporting a variant of unknown significance (n = 49) or negative finding (n = 419) held discussions 38.8% and 38.0% of the time, respectively (P < .001).
“Our findings support a rapidly growing movement to simplify clinical guidelines to increase access to genetic testing and clinical impact of the results after diagnosis and into survivorship,” lead study author Steven J. Katz, MD, MPH, professor of internal medicine and health management and policy at the University of Michigan, stated in a press release on the study findings.2
The population-based longitudinal survey enrolled collected baseline responses from 2502 women 20 to 79 years with newly diagnosed early-stage breast cancer from 2014 to 2015. A paper follow-up with an online survey option was sent out 6 years after initial diagnosis for the eligible respondents, which excluded deceased patients (n = 108) and those too ill (n = 33) to participate. Of those eligible for follow-up (n = 2361), 1412 (59.8%) completed the survey.
End points were measured based on responses to the follow-up survey. Questions included time since last genetic counseling appointment, time since last blood or saliva genetic test, the results of the most recent genetic test, patient knowledge of and participation in a direct-to-consumer genetic test, and whether a patient’s results were disclosed with their immediate family.
Patents who reported receiving genetic testing within 2 years of the survey included 13.0% of baseline indication testers and 19.5% in the follow-up, only (P < .001). Survey responses showed that 3.5% of survivors had a second primary breast cancer since initial diagnosis and 1.5% had a metastatic recurrence.
Of respondents, 5.1% had researched direct-to-consumer genetic testing, with only 3.4% of survivors undergoing it. Although follow-up responses differed by numerous patient characteristics, weighted analyses showed no meaningful differences in results.
“In conclusion, germline genetic testing is increasingly important after a diagnosis of cancer, for treatment management and for cancer risk reduction in families with hereditary cancer syndromes. While it is ideal to obtain genetic testing results during treatment planning, the survivorship period remains a major missed opportunity to engage patients and family members who may be at risk for hereditary cancer susceptibility and may be candidates for effective risk reduction and treatment strategies,” Katz and coinvestigators concluded in the publication.1