Concordance of mutation detection in circulating tumor DNA in early clinical trials using different blood collection protocols

TY - JOUR

T1 - Concordance of mutation detection in circulating tumor DNA in early clinical trials using different blood collection protocols

AU - Ahlborn, Lise B.

AU - Madsen, Mette

AU - Jonson, Lars

AU - Nielsen, Finn C.

AU - Lassen, Ulrik

AU - Yde, Christina W.

AU - Mau-Sorensen, Morten

PY - 2017

Y1 - 2017

N2 - Background: Small fragments of tumor DNA can be found in the circulation of cancer patients, providing a noninvasive access to tumor material (liquid biopsy). Analysis of circulating tumor DNA (ctDNA) has been used for diagnosis, treatment decisions, and detection of therapy resistance, including in patients with tumors inaccessible for biopsy, making ctDNA an important alternative source of tumor material. Immediate separation of plasma is widely used in standard isolation of cell-free DNA to ensure high quality plasma DNA. However, these procedures are labor intensive and logistically challenging in a clinical setting. Here we investigate the concordance between standard blood collection for molecular analysis using immediate separation of plasma, compared to the use of collection tubes allowing for delayed processing. Methods: In this study, we measured the fractional abundance of tumor specific mutations (BRAF p.V600E and PIK3CA p.H1047R) in ctDNA isolated from blood samples collected in either cell-stabilizing Cell-Free DNA BCT tubes (delayed processing within 72 hours) or standard K3EDTA tubes (immediate processing within 15 minutes). Twenty-five blood sample pairs (EDTA/BCT) were collected from patients with advanced solid cancers enrolled in early clinical trials. Results: Concordance in the fractional abundance of mutations in ctDNA isolated from blood collected in either K3EDTA or BCT tubes from patients with different solid cancers was observed. Conclusions: This study indicates that BCT tubes are preferable for collection of circulating DNA in a clinical setting due to the favorable storage and shipping conditions.

AB - Background: Small fragments of tumor DNA can be found in the circulation of cancer patients, providing a noninvasive access to tumor material (liquid biopsy). Analysis of circulating tumor DNA (ctDNA) has been used for diagnosis, treatment decisions, and detection of therapy resistance, including in patients with tumors inaccessible for biopsy, making ctDNA an important alternative source of tumor material. Immediate separation of plasma is widely used in standard isolation of cell-free DNA to ensure high quality plasma DNA. However, these procedures are labor intensive and logistically challenging in a clinical setting. Here we investigate the concordance between standard blood collection for molecular analysis using immediate separation of plasma, compared to the use of collection tubes allowing for delayed processing. Methods: In this study, we measured the fractional abundance of tumor specific mutations (BRAF p.V600E and PIK3CA p.H1047R) in ctDNA isolated from blood samples collected in either cell-stabilizing Cell-Free DNA BCT tubes (delayed processing within 72 hours) or standard K3EDTA tubes (immediate processing within 15 minutes). Twenty-five blood sample pairs (EDTA/BCT) were collected from patients with advanced solid cancers enrolled in early clinical trials. Results: Concordance in the fractional abundance of mutations in ctDNA isolated from blood collected in either K3EDTA or BCT tubes from patients with different solid cancers was observed. Conclusions: This study indicates that BCT tubes are preferable for collection of circulating DNA in a clinical setting due to the favorable storage and shipping conditions.

KW - Blood collection tubes

KW - Circulating tumor DNA

KW - Droplet digital PCR

KW - Early clinical trials

KW - Mutant allele fraction

U2 - 10.7754/Clin.Lab.2017.170516

DO - 10.7754/Clin.Lab.2017.170516

M3 - Journal article

AN - SCOPUS:85032720913

SN - 1433-6510

VL - 63

SP - 1755

EP - 1759

JO - Clinical Laboratory

JF - Clinical Laboratory

IS - 10

ER -