Clinicians struggle with interpreting genetic testing results, even after taking educational courses, according to a new study
Emily Edelman, associate director of clinical and continuing education at the Jackson Laboratory, and her colleagues examined how well clinicians fared on quizzes assessing their grasp of certain key cancer genetic testing concepts after they completed one of the Jackson Lab courses.
Most of the nearly 800 individuals who took a post-course quiz understood how to deal with positive genetic testing results, but they had difficulties interpreting negative results and variants of uncertain significance.
The target demographic of these courses was primary care providers, Edelman said, but she noted that their study population included people from a number of specialties like oncology, genetics, primary care, and surgery.
The course takers struggled with interpreting negative results or variants of uncertain significance. About 13 percent were falsely reassured with uninformative negative results, such as when a patient with a clinical diagnosis for a hereditary cancer syndrome received a negative result.
Additionally, nearly 60 percent could not interpret a true negative result. This, she said, is a scenario in which a known pathogenic variant has been found in an unaffected patient’s family member and the patient tests negative for it. About 40 percent of the course takers said that a person would still be at increased risk of developing cancer and 20 percent said that a person’s risk was unknown.
Interpreting variants of uncertain significance also posed problems for participants, as about 40 percent said they’d suggest testing of their unaffected patient if a sibling was found to have a VUS in BRCA1, which is not recommended.
Meanwhile, doctors in India points out to the localised approach in the investigation considering the variations in the disease profile and affordability would be helpful for the wider use.
“There is ample evidence that these new diagnostic technologies like molecular and genetic testing influence clinical decision making. It has definitely created an impact on many go and no-go decisions for clinicians, especially in oncology, on better diagnosis and treatment and even to predict the treatment outcome,” says Dr Santhosh Dixit at Prashanti Cancer Care Centre, Pune.
But, the only problem is the affordability as many of these tests are not available in India. If the companies can bring down the cost, definitely there will be more acceptance and uptake. And the other issue is that since most of these tests are designed according to disease profile of the original country, it needs to be localised according to the respective variations for better results, he added.
Dr Padmanabha Shenoy, a senior rheumatologist, said that the new technologies have prompted a sea change in the way the diagnosis and the treatments are done and the specificity has increased. This has really benefited the patents in terms of the outcome as well as the cost of treatment. “As it is the case everywhere, there is resistance to new technologies especially when it comes to patient care as none would want to take a risk by shifting to entirely new technology. But once the knowledge is disseminated and awareness is created this resistance will slowly disappear,” he added.