More than a decade after the successful mapping of the human genome, clinical genomics is starting to permeate important parts of patient care. Studies show that about 60% of primary care physicians (PCPs) have ordered a genetic test for breast cancer, colon cancer, sickle cell disease, or Huntington disease. Another 75% of PCPs have referred patients for genetic testing. So-called “personalized medicine” routinely guides therapy in HIV disease, and use of targeted anti-cancer drugs is rising.
While 98% of physicians in a recent national poll agreed that genetic testing is useful, just 10% reported that they felt adequately informed about using it. Doctors need clarity on integrating genomics into routine practice.
A Growing Challenge for Genetic Testing
As of 2011, 76 drugs had documented biomarker information that is available to guide prescribing practices. Those biomarkers affected 18 therapeutic areas, from heart disease to depression. Meanwhile, a major update of Current Procedural Terminology billing codes in 2012 is expected to include more than 100 genetic procedures, making these tests easy to order. Unfortunately, less than 3% of published research articles on genomics that were released between 2002 and 2006 included information on translating research into practice. Just 1.8% of cancer genetics grants in 2007 that were issued by the National Cancer Institute went to translational research. Furthermore, just 0.6% of publications on the topic dealt with translational issues.
Testing for BRCA1/2 genetic mutations illustrates the dilemma practicing clinicians face. Ashkenazi Jews, for example, are at much higher risk for BRCA1/2 genetic mutations than the general population, with 2.5% of Ashkenazi Jews carrying these genes compared with about 0.02% of the general public. Some Jewish organizations urge women to consider testing, but the United States Preventive Services Task Force (USPSTF) recommends this genetic analysis only for those whose family history indicates increased risk. At the same time, there are concerns minority women are being under-tested for BRCA1/2 genetic mutations.
The USPSTF offers guidelines, but they include seven clinical scenarios; about 20% of PCPs correctly identified them all in a recent study. Meanwhile, a 2008 malpractice case ruling involving BRCA genetic mutations established that cost is not a defense for recommending against testing if it’s medically warranted. It’s no surprise that appropriate use of this test and others is subpar. There have been reports of patients receiving repeated molecularly testing despite lack of evidence of those tests’ clinical validity.
Making a Move Forward with Clinical Genomics
Professional groups, such as the National Comprehensive Cancer Network, are beginning to provide better clinical decision support systems. However, the most physician-friendly implementation infrastructure is being built by private firms. They’re offering services such as:
A menu of tests.
Phone and web-based advice for clinicians and patients.
A payment policy database.
Cancer Commons, an open-science initiative, reaches out to patients directly, helping them find treatments based on tumor characteristics and asking them to share what they’ve learned with their doctor, researchers, and other patients. Whether these types of groups initiating such activities will contribute to better outcomes or simply increase the use of clinical genomics remains to be seen. Fortunately, the field is advancing rapidly. As clinical genomics continues to move from bench to bedside, better patient care demands better and more usable information for front-line caregivers.
Readings & Resources (click to view)
Bellcross CA, Kolor K, Goddard KA, et al. Awareness and utilization of BRCA1/2 testing among U.S. primary care physicians. Am J Prev Med. 2011;40:61-66.
Burke W, Laberge AM, Press N. Debating clinical utility. Pub Health Genomics. 2010;13:215-223.
Feero WG, Guttmacher AE, Collins FS. Genomic medicine – an updated primer.” N Engl J Med. 2011;362:2001-2011.
Millenson, ML. How can we move clinical genomics beyond the hype? Urban Institute. 2011:1-13. Accessed at: http://www.urban.org/health_policy/url.cfm?ID=412426.
PharmGKB. Pharmacogenomic Knowledge Base. Accessed at: http://www.pharmgkb.org/.
Schully SD. Translational research in cancer genetics: the road less traveled. Pub Health Genomics. 2011;14: 1-8.