Detection of Circulating Tumor DNA (ctDNA) in Blood: Standardization of Pre- and Post-Analytical Conditions
What you will learn:
- ctDNA yields depends on type of blood collection tubes and available time to plasma processing
- Automated cfDNA isolation platforms can replace the standard more laborious manual isolation method for high-throughput fast, reproducible, and efficient isolation of ctDNA
- Fragment size analyses of cfDNA helps to identify optimal specimen for ctDNA detection
Summary
Circulating tumor DNA (ctDNA) in longitudinal collected blood samples can be used to monitor disease progression and therapy response. In this webinar, Dr. Maurice Jansen presents his liquid biopsy workflow for cfDNA analysis and ctDNA detection at the Erasmus Medical Center, Rotterdam Netherlands. Their goal is to apply ctDNA detection in prospective (multicenter) clinical trials, therefore, the effects of various pre- and (post-)analytical conditions on the quality of cfDNA in general and of ctDNA in particular were investigated. As pre-analytical factors they evaluated the choice of blood collection tubes and the time to plasma processing on the cfDNA and ctDNA yields. Their results demonstrated that different preservatives in tubes did not affect somatic variant detection ability, but stabilized cfDNA concentrations over time. Only EDTA tubes had a time-dependent increase in cfDNA concentrations, which was positively correlated with an increase in wild-type copy numbers and large DNA fragments (>420 bp). As (post-)analytical factor, they compared the manual cfDNA isolation method with two automated cfDNA isolation platforms (Maxwell (Promega) and QIAsymphony) for high-throughput isolation of ctDNA. All platforms isolated preferentially small (136 bp) DNA fragments over large (420 and 2000 bp) DNA fragments. No significant difference in variant allele frequency was observed between all platforms, although Maxwell had the lowest wild-type copy cfDNA numbers.
Speaker
Maurice PHM Jansen, PhD
Senior Scientist, Erasmus MC, University of Medical Center
Rotterdam, Netherlands
Maurice PHM Jansen is a molecular cell biologist in the Department of Medical Oncology at Erasmus MC, University Medical Center at Rotterdam, Netherlands. He received his Ph.D. at the Department of Internal Medicine at the Academic Hospital Maastricht, Netherlands. As senior scientist he collaborates closely with clinicians and researchers to optimize liquid biopsy analyses for genomic alteration monitoring over time and relate these biomarkers with disease and treatment outcome.