The molecular diagnostics company Veracyte Inc. has announced the development of a new test that could potentially replace invasive lung biopsies that are considered unsafe and expensive.
The Percepta Bronchial Genomic Classifier, co-developed by researchers from the Boston University (BU) School of Medicine, retrieves gene samples from a patient's windpipe and analyzes 23 of these depending on their reaction to cigarette toxin exposure.
Dr. Avrum Spira of Boston University said the cells taken using the classifier can be compared to a canary used by coal miners. Doctors can use these cells to identify if a nodule in a patient's lung is likely to develop cancer.
Previous diagnostics tests involve inserting a small camera down a patient's windpipe in order to view the affected area of the lung. The procedure, however, has a 40 percent chance to fail in producing a clear diagnosis. This is because the scope often fails to reach the specific part of the lung being tested.
"The only way we can be definitive is to stick a needle through the chest wall or cut open your chest," Spira said. "We don't want to miss a cancer, so we end up operating on and biopsying a lot of people who don't have cancer."
After undergoing CT scan and bronchoscopy, patients are classified as low, intermediate or high risk for cancer.
Spira explained that the Veracyte test is designed to focus on the intermediate-risk group, re-classifying many of the patients as low risk with a degree of accuracy of about 91 percent. The results of the test provide an opportunity for patients to be monitored using CT scans instead of having to go through biopsies.
"We now have a new tool to help us evaluate smokers who are at risk for having lung cancer and identify those who don't need to undergo invasive procedures," Spira said.
In their study, published in the New England Journal of Medicine, Spira and his colleagues tested the Percepta Bronchial Genomic Classifier using two experiments involving 639 patients (298 in AEGIS I and 341 in AEGIS II) who were undergoing bronchoscopy.
The researchers collected cells from the airways of these patients and proceeded to conduct a genomic test.
By combining the Genomic Classifier along with a bronchoscopy, they were able to detect lung cancer in patients with 97 percent sensitivity. A bronchoscopy alone only yielded an accuracy of 75 percent.
"These rigorous studies represent the largest evaluation to date of patients undergoing bronchoscopy, and establish the performance and utility of our Percepta Bronchial Genomic Classifier in lung cancer diagnosis," Bonnie H. Anderson, president and chief executive officer of Veracyte, said.
"By helping to prevent unnecessary invasive diagnostic procedures, the Percepta test should provide very tangible benefits for patients and physicians, while removing costs from the healthcare system."
Photo: Chuck Grimmett | Flickr
