GeneStrat Test Provides Quick Analysis of Genetic Lung Cancer Mutations Interview with:
Hestia Mellert, PhD

Director, Molecular Product Development
Biodesix: Making Medicine Personal
Boulder, CO What is the background for this study? What are the main findings?

Response: Identifying specific genetic mutations in non-small cell lung cancer patients helps clinicians choose the best treatment options; specific therapies that target mutations can improve patient outcomes, including reducing the risk of death or lessening the severity of the disease. However, nearly 80% of cancer patients do not have genetic mutation results available at initial oncology consultation; up to 25% of patients begin treatment before receiving their results. These factors hinder physicians’ ability to pursue optimal treatment strategies.

This study found that a blood-based assay, the GeneStrat test, provides results in 72 hours for 94% of patients, which expands testing options, and supports faster treatment decisions by physicians. What should readers take away from your report?

Response: Blood-based mutation testing in clinical practice can accelerate time to treatment, and testing with ddPCR is a reliable and robust method for identifying actionable mutations. Combined clinical validation data for all evaluated mutation variants demonstrated a high mean sensitivity, specificity, and concordance of 90.0%, 100%, and 97.0%, respectively. Turnaround time was also calculated for 1,643 samples submitted for the GeneStrat test. This test service is particularly relevant in the community setting, where physicians and patients may not have easy access to a large hospital or other diagnosis/treatment facilities and instead use supplied kits from Biodesix to draw blood and ship samples to our regulated laboratory for testing. The GeneStrat test expands options for patients diagnosed with cancer and may expedite time to treatment. What recommendations do you have for future research as a result of this study?

Response: One of the unique findings of this study was the approach of evaluating fusion transcripts resulting from the EML4-ALK rearrangement. In addition to cell-free DNA, we expect that the utility of circulating RNA in diagnostics will continue to grow. This is another very useful and clinically relevant approach, but underutilized today in blood testing. Testing for circulating nucleic acids also has the distinct advantage of being more patient-friendly, requiring a minimally invasive blood draw and low volumes of blood.

We also expect that turnaround times will significantly decrease and are working on these approaches. We further anticipate that we will see adoption of targeted testing approaches like the ones described here for monitoring cancer burden during treatment. We are very excited to be a part of the development of clinical laboratory tests that enable this type of testing in the future. Is there anything else you would like to add?

Response: The authors of the paper were either employees of Biodesix Inc. or Bio-Rad Digital Biology Center. Biodesix has filed a patent application covering a diagnostic test system for the detection of circulating genetic variants in non-small cell lung cancer. Thank you for your contribution to the community.


Hestia Mellert, Trudi Foreman, Leisa Jackson, Dianna Maar, Scott Thurston, Kristina Koch, Amanda Weaver, Samantha Cooper, Nicholas Dupuis, Ubaradka G. Sathyanarayana, Jakkie Greer, Westen Hahn, Dawne Shelton, Paula Stonemetz, Gary A. Pestano. Development and Clinical Utility of a Blood-Based Test Service for the Rapid Identification of Actionable Mutations in Non–Small Cell Lung Carcinoma. The Journal of Molecular Diagnostics, 2017; 19 (3): 404 DOI: 10.1016/j.jmoldx.2016.11.004

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.
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Last Updated on April 25, 2017 by Marie Benz MD FAAD