Germline Genetic Testing in Advanced Prostate Cancer; Practices and Barriers: Survey Results from the Germline Genetics Working Group of the Prostate Cancer Clinical Trials Consortium

Abstract

Background: Germline genetic testing increasingly identifies advanced prostate cancer (PCa) patients who are candidates for precision therapies. The Prostate Cancer Clinical Trials Consortium (PCCTC) established the Germline Genetics Working Group to provide guidance and resources to expand effective use of germline genetic testing.

Materials and methods: A 14-item questionnaire was e-mailed to academic oncologists at 43 PCCTC sites to collect information on germline genetic testing patterns, including patients considered, choice of assays, barriers slowing adoption, and actions to overcome barriers.

Results: Twenty-six genitourinary oncologists from 19 institutions responded. Less than 40% (10 of 26) reported referring patients to a genetics department, whereas the remainder take personal responsibility for genetic testing and counseling; 16 (62%) consider testing all metastatic PCa patients, whereas 3 (12%) consider testing all patients with high-risk local disease; and 7 (27%) use multigene comprehensive pan-cancer panels, and 14 (54%) use smaller or targeted cancer gene panels. Barriers to widespread use are: (1) delayed or limited access to genetic counseling; (2) no insurance coverage; (3) lack of effective workflows; (4) insufficient educational materials; and (5) time and space constraints in busy clinics. The primary limitation was the <50% (19 of 43) response from PCCTC sites and no coverage of nonacademic cancer treatment facilities.

Conclusion: Joint efforts by urologists, oncologists, genetics counselors, insurers, and cancer centers can accelerate implementation of integrated germline genetic services for personalized treatment and clinical trial eligibility for PCa patients.

Keywords: BRCA; DNA repair; Lynch; PARP inhibitors; Pembrolizumab.

Figure 1:. Provider Considerations of Germline Testing Among Men with Prostate Cancer

Note: Panel A: Men with mPCa considered for germline testing; Panel B: Men with high-risk localized and biochemically recurrent PCa considered for germline testing; Panel C: Factors affecting decision to test; Panel D: Factors affecting decisions on results. Abbreviations: +, positive results; −, negative results; BCR, biochemically recurrent; GC, genetic counselor; HRL, high risk localized; N, no; NC, no post-test genetic counseling; NT, no germline genetic testing; PCa, prostate cancer; VUS, variant of uncertain significance; Y, yes.