The Abramson Cancer Center of the University of Pennsylvania
Ultima Vez Modificado: 18 de mayo del 1996
Would you want to know if you are at an approximately 90% risk of developing breast and/or ovarian cancer at some point in your life, perhaps even before the age of 40? The availabiility of the DNA test for BRCA1 mutations has raised questions and issues that go beyond clinical diagnosis, and involve legal, ethical, and emotional aspects. Public demand for DNA testing is increasing dramatically, despite controversy among experts regarding who should be tested, when testing should occur, who should pay for it, and what should be done with the results. New clinical research and presentations to address this topic were discusssed today at the 32nd American Society of Clinical Oncology (ASCO) Annual Meeting.
"The genetic testing debate is likely to continue for some time, until long-term research on the impact of these tests can be conducted," said Barbara L. Weber, M.D., associate professor and director, Breast Cancer Program, University of Pennsylvania Cancer Center (Philadelphia, PA), at a press briefing today. "In the short-term, an open discussion about all aspects of genetic testing will assist physicians and the public in making informed decisions."
Philip R. Reilly, M.D., J.D., president, chief executive officer, Shriver Center for Mental Retardation (Waltham, MA), discussed the ethical and legal implications of genetic testing. According to Dr. Reilly, rapid advances in genetic testing promise significant clinical advances in the ability to predict risk, develop effective interventions, refine prognosis and discover new approaches to therapy. Unfortunately, the actual clinical benefits that genetic information confers have neither been fully explored nor confirmed, and it may be years before the medical community is confident in interpreting the implications of genetic status.
The ability to identify genes that increase risk for cancer and other disorders has outpaced the medical community's ability to intervene constructively. According to Dr. Reilly, this is the central dilemma that molecular genetics poses for oncology. A host of questions need to be addressed in order to use genetic information in a meaningful way. For example, who should have access to genetic infomration? For what purposes should it be legitimately used? What impact will there be on the confidentiality of the patient-physician relationship?
In addition, Dr. Reilly discussed one of the more troubling aspects of genetic testing for cancer susceptibility -- the potential threat to insurability and employment posed by the ability to discern genetic risk information. Dr. Reilly suggested that the strongly-held public concerns about privacy issues may compromise and threaten research involving DNA.
"Genetic testing is a double-edged sword, because while we can help identify certain people who are at an increased risk of developing cancer, we can't guarantee that this information will not be used improperly," said Dr. Weber. "Legislation to protect genetic risk information and confidentiality must be implemented if clinical research in this area is to continue."
Kenneth Offit, M.D., M.P.H. chief, Clinical Genetics Service, Department of Human Genetics, Memorial Sloan-Kettering Cancer Center (New York, NY), presented an overview of the recently issued ASCO position statement regarding genetic testing for cancer susceptibility. To assist ASCO's 10,000 members in responding to the growing interest in genetic testing, the Society developed a statement to advise clinical oncologists about the critical issues that must be addressed if genetic testing is to be responsibly and effectively translated into the care of patients with cancer and their families.
Earlier statements by professional societies recommended limiting cancer genetic predisposition testing only to research studies. However, genetic testing is or will be commercially available outside of the context of clinical research. According to Dr. Offit, during the transition period while testing is integrated into the standard medical care of patients, physicians must exercise caution.
Informed consent of the patient of family members is the cornerstone of the ASCO statement, including implications of a positive or negative result; risk of passing a mutation on to children; technical accuracy of the test; fees involved in counseling and testing; and risk of psychologiscal distress. The statement also urges that counseling be offered to all individuals at hereditary risk for cancer. Additionally, patients and their families should be informed about the potential for genetic discrimination by insurers or employers.
To ensure that oncologists comply with these recommendations, ASCO is developing educational programs specific to genetic testing for cancer susceptibility. Until these programs are available, ASCO is urging oncologist to obtain consultations from colleagues with expertise in cancer genetic testing.
Dr. Offit, who chaired the ASCO Subcommittee on Genetic Testing for Cancer Susceptibility, also highlighted the need for high quality genetic and counseling testing and counseling services. Dr. Offit explained that ASCO supports legislative and regulatory efforts to ensure access to genetic testing, require coverage of and reimbursement for these services by public and private third-party payers, and improve the oversight of laboratories providing testing. In addition, Dr. Offit affirmed the critical need for research directed at specifying more precisely the clinical significance of mutations in cancer susceptibility genes, and endorsed the concept of a national registry and protocol with full confidentiality.
"The landscape is changing as cancer genetic testing becomes commercially available," said Dr. Weber. "Clinical oncologists and patients should benefit from having a clearly articulated position statement from ASCO. We hope that adherence to these guidelines will provide the framework for the appropriate use of this new technology."