Comparison of methods for measuring total cell-free DNA and KRAS mutations in plasma from metastatic colorectal cancer patients

Date 29 June 2016
Event ESMO World Congress on Gastrointestinal Cancer 2016
Session ESMO World Congress on Gastrointestinal Cancer 2016 - Abstracts book
Presenter C. Demuth
Citation Annals of Oncology (2016) 27 (2): 1-85. 10.1093/annonc/mdw199
Authors C. Demuth1, K.-.G. Spindler2, J.S. Johansen3, N. Pallisgaard4, D. Nielsen3, E. Hoegdall5, B. Vittrup3, B. Sørensen1
  • 1Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark, /
  • 2Department of Oncology, Aarhus University Hospital, Aarhus, Denmark, /
  • 3Department of Oncology, Herlev and Gentofte Hospital, Herlev, Denmark, /
  • 4Department of Surgical Pathology, Zealand University Hospital, Roskilde, Denmark, /
  • 5Department of Pathology, Herlev Hospital, Herlev, Denmark, /


Measurements of total cell-free DNA (cfDNA) and circulating tumor DNA (ctDNA) in plasma has presented as a new tool for selection of the optimal therapy for cancer patients, and studies have shown that measuring the total level of cfDNA or tumor-specific mutations in KRAS bears prognostic value in metastatic colorectal cancer (mCRC).


The aim of this study was to identify the most robust method for detection of total cfDNA and KRAS mutations in plasma samples. A multiplex droplet digital PCR (ddPCR) for measuring total cfDNA and a control for contamination with lymphocytes was used. Further, two different assays for measuring KRAS mutations on ddPCR were set up and compared internally as well as to next generation sequencing (NGS), to allow identification of the best strategy for future studies. In addition, we investigated if measuring total cfDNA in small-volume samples (200 µL plasma) was sufficient for prognostic purposes.