Abstract 2758: Comparison of cell-free DNA blood collection tubes
Authors: Browne Cecille D. , Mattmann Margrith E. , Wycoco Marc J. , Chen Sheila N. , Ravichandran Rajeswari , Desharnais Joel , Varela Laura J. , Browne Jonathan D. , Liberal Vasco , Lee Florence 
Published: July 2017

Critical biomarkers such as cell-free DNA (cfDNA) derived from tumors and circulating tumor cells (CTCs) can be detected and analyzed from a simple blood draw. These analytes are fragile, prone to degradation, and present in extremely low quantities. Therefore, proper preservation of these analytes is necessary to ensure accuracy of test results. Several blood collection tubes are commercially available for cfDNA applications, and selecting the ideal blood collection tube for cfDNA impacts test results, sample collection logistics and costs. However, no comprehensive and systematic evaluation of performance among these tubes is available. This study evaluates five commercial blood collection tubes: LBgard™ Blood Tube (Biomatrica), Streck cfDNA BCT® (Streck), PAXgene Blood ccfDNA Tube (PreAnalytiX), Cell-Free DNA Collection Tube (Roche), and EDTA (BD). Healthy donor blood samples were collected in each tube type and incubated over several days at different temperatures. Total plasma DNA was subsequently isolated, and the yield, fold increase versus time 0 and quality of purified DNA were compared. cfDNA controls were also spiked into blood samples collected in each tube type and measured by droplet digital PCR to determine the mutant allele frequencies over time. Finally, the yield and quality of cfDNA isolated from stage IV colorectal cancer blood collected in LBgard Blood Tube, Streck cfDNA BCT and EDTA were compared. Additionally, the inhibition of hemolysis and CTC stabilization were also assessed. Our results show that LBgard Blood Tube, Streck cfDNA BCT, PAXgene ccfDNA Tube and Cell-Free DNA Collection Tube are superior to EDTA tubes in maintaining cfDNA yield and quality over 7 days at ambient temperature. LBgard Blood Tube out-performs all tested blood tubes in inhibiting genomic DNA release for the longest duration (14 days) and across the widest temperature range (4°C, 25°C and 37°C). LBgard Blood Tube shows equivalent inhibition of genomic DNA release to Streck cfDNA BCT for clinical samples, and both tubes out-perform EDTA blood tubes. LBgard Blood Tube also consistently shows better CTC stabilization and inhibition of hemolysis over Streck cfDNA BCT. This comprehensive and systematic study of blood collection tube performance provides a quantitative and exhaustive assessment of blood sample stability, allowing researchers to make informed decisions based on their sample stabilization needs.

Citation Format: Cecille D. Browne, Margrith E. Mattmann, Marc J. Wycoco, Sheila N. Chen, Rajeswari Ravichandran, Joel Desharnais, Laura J. Varela, Jonathan D. Browne, Vasco Liberal, Florence Lee. Comparison of cell-free DNA blood collection tubes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2758. doi:10.1158/1538-7445.AM2017-2758