from Genetic Engineering News –
Investigators at the Abramson Cancer Center at the University of Pennsylvania (ACC) have just released data from a new study that suggests a noninvasive liquid biopsy test may be a more efficient and suitable alternative to the gold standard tissue biopsy to detect clinically relevant mutations for advanced lung cancer patients and help guide their course of treatment. This new study builds a case for increased clinical use of the molecular diagnostic technique addressing an unmet need for better, noninvasive tests, which was recently called out in the Cancer Moonshot Blue Ribbon Panel Report.
The ACC researchers studied non-small-cell lung cancer (NSCLC) and were able to detect mutations from liquid biopsy blood samples that analyzed cell-free circulating tumor DNA (ctDNA). The scientists found that the mutations picked up by the liquid biopsy samples closely paralleled mutations from tissue biopsies identified using next-generation sequencing (NGS) tests, such as epidermal growth factor receptor (EGFR), tumor protein 53 (TP53), and anaplastic lymphoma kinase (ALK). Moreover, there were several instances where liquid biopsies captured clinically relevant mutations not found in tissue biopsies as patients’ disease progressed.
Interestingly, about half of the 102 patients in this study did not have sequenceable biopsy tissue, so researchers relied on blood tests to detect mutations. Also, investigators are now seeing the emergence of targetable resistance mutations in advanced NSCLC as the disease progresses and therapies change—which is much more achievable with serial blood samples used for liquid biopsy.
“This represents a bit of a paradigm shift,” explained senior study investigator Erica Carpenter, Ph.D., director of the Circulating Tumor Material Laboratory and research assistant professor at the Perelman School of Medicine within the University of Pennsylvania. “The tissue biopsy sequencing result has been considered the gold standard against which one compares the ctDNA result. Our work suggests that one can act on a ctDNA result, even in the absence of the so-called gold standard, and get a clinical response in these patients. It also offers the advantage of testing without discomfort to the patient and possible risks associated with invasive biopsies.”