Quantitative and qualitative characterization of plasma DNA identifies primary and recurrent colorectal cancer

Cancer Lett. 2008 May 18;263(2):170-81. doi: 10.1016/j.canlet.2008.03.021.


Because plasma DNA may be a useful tool for cancer detection, we screened primary tumors and related multiple plasma samples at the time of surgery and during the follow-up period for plasma DNA level as well as for K-Ras mutations and p16INK4a promoter hypermethylation in colorectal cancer patients. At the time of surgery, DNA levels were higher in tumor patients than in healthy donors, and K-Ras and p16INK4a alterations were detected in 7 and 11 cancers respectively, and in all related plasma samples. During the follow-up, plasma DNA levels decrease progressively but rapidly increased when a relapse occurred, whereas K-Ras and p16INK4a alterations were detected only in relapsed patients. Therefore, combined quantitative and qualitative analyses of plasma DNA confirm the presence of colorectal cancer, define disease-free status and indicate the presence of relapse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / blood*
  • Adult
  • Aged
  • Aged, 80 and over
  • Colorectal Neoplasms / blood*
  • DNA Methylation
  • DNA, Neoplasm / blood*
  • Female
  • Genes, p16
  • Genes, ras
  • Humans
  • Male
  • Middle Aged
  • Mutation
  • Plasma / chemistry*
  • Platelet Endothelial Cell Adhesion Molecule-1 / analysis


  • DNA, Neoplasm
  • Platelet Endothelial Cell Adhesion Molecule-1