February 2019

Keys to Better Liquid Biopsy Assay Sensitivity

“So as everyone here is aware, I’m sure, detection of circulating tumor DNA is challenging. There’s very little of it, to start with.” Hardly a revolutionary statement by Tony Godfrey, PhD, (Associate Chair, Surgical Research and Associate Professor of Surgery, Boston University School of Medicine) but an important acknowledgement from a leading expert of the difficulty faced by laboratorians in unlocking the full promise of liquid biopsy assays. Both he and Bob Daber, PhD, (President and CTO of Genosity) detailed how they overcame common ctDNA challenges in their labs during SeraCare’s AMP Corporate Workshop in San Antonio, Texas. Watch the video to see the practical advice they gave in their presentations.

Bob Daber, with whom we collaborated on our NGS-based assay validation eBook, discussed the challenges that are unique or more pronounced in ctDNA assay validation. Chief among them being limited access to samples for the variety of studies needed to have true confidence in your assay. Drawing on his years of clinical genomics and bioinformatics expertise, including building the tumor sequencing lab at BioReference, Dr Daber talked about how ground-truth data from known-negative and known-positive materials are critical to determining your assay’s sensitivity and specificity; two attributes that take on even greater importance in liquid biopsy.

Tony Godfrey’s presentation highlighted how access to patient-like ctDNA reference standards allowed his team to refine their SiMSen-Seq technology by reducing background error rates, evaluating absolute copy numbers, and improving sensitivity. Dr Godfrey talked about how his team was able to confidently detect  0.1% mutant allele frequency, and how ground-truth reference materials help them improve performance. Something that wouldn’t have been possible with the inherent variability and scarcity of remnant specimens.

Both presentations are full of actionable information and instructive data from the speakers’ own labs. Watch the video for free today to learn how you can have more confidence in your liquid biopsy assay.


This blog post was originally published on the SeraCare blog.