Cancer Experts Develop Precision Medicine-Based Genetic Testing Framework for Prostate Cancer
June 10, 2020 (360Dx.com) NEW YORK – An international panel of cancer researchers has published a multidisciplinary, consensus-driven framework for genetic testing of prostate cancer patients.
As the researchers wrote in their paper, which was published Tuesday in the Journal of Clinical Oncology, germline testing is a central feature of prostate cancer treatment and management, but there are several critical needs, including optimized multigene testing strategies that incorporate evolving genetic data, consistency in germline testing indications and management, and alternate genetic evaluation models that address the rising demand for genetic services.
The overarching questions the researchers sought to address were the primary drivers of the conceptual framework: Which men should be considered for germline prostate cancer genetic testing? Which panels should be considered and which genes should be prioritized for testing? What prostate cancer-specific recommendations should be considered on the basis of genetic results? What is optimal informed consent for prostate cancer germline testing? What collaborative strategies may facilitate prostate cancer genetic evaluation between healthcare and genetic providers? What post-test disclosure strategies are most appropriate on the basis of genetic results? What barriers must be addressed to enhance prostate cancer germline testing?
The framework they developed included criteria with strong agreement by 75 percent of the panel, which were termed Recommend, or moderate agreement by 50 percent to 74 percent of the panel, which were termed Consider.
The panel recommended large germline panels and somatic testing for metastatic prostate cancer. They also recommended germline testing for metastatic disease or family history suggestive of hereditary prostate cancer. Additional family history and pathologic criteria garnered moderate consensus. Priority genes to test for metastatic disease treatment included BRCA2, BRCA1, and mismatch repair genes, with broader testing, such as ATM, for clinical trial eligibility. The panel recommended BRCA2 for active surveillance discussions, while screening starting at age 40 years or 10 years before the youngest prostate cancer diagnosis in a family was recommended for BRCA2 carriers, with consideration in HOXB13, BRCA1, ATM, and mismatch repair carriers.
The panel also developed point-of-care evaluation models for healthcare and genetic providers to work collaboratively to address the genetic counseling shortage. The genetic evaluation framework included optimal pretest informed consent, post-test discussion, cascade testing, and technology-based approaches.
“Models of genetic evaluation that incorporate technology to enhance access to genetic testing, such as telehealth or use of videos for pretest genetic education, were also endorsed, along with key elements of informed consent so men can make an informed decision for genetic testing,” lead study author Veda Giri, director of the Cancer Risk Assessment and Clinical Cancer Genetics Program and the Men’s Genetic Risk Clinic at the Sidney Kimmel Cancer Center of Thomas Jefferson University, said in a statement.
“Germline mutations are found in 12 to 17 percent of men with metastatic prostate cancer and 7 percent of men with early-stage disease. A patient’s genetic information may inform how healthcare providers screen, diagnose, and treat prostate cancer, as well as enable them to enroll in a clinical trial,” Giri added. “Therefore, this implementation framework applies to oncologists, urologists, genetic counselors, and primary care providers engaged in the care of men with prostate cancer or at risk for the disease.”
The researchers on the panel also noted that data from screening studies, such as IMPACT and the National Cancer Institute, should be used in the future to strengthen these recommendations. This is the first time that screening strategies based on a larger genetic spectrum have been proposed, they added, and additional research in African-American males is vitally needed. Future consideration of circulating tumor and cell-free DNA is also warranted, they said.