Prognostic significance of the detection of peripheral blood CEACAM5mRNA-positive cells by real-time polymerase chain reaction in operable colorectal cancer

Clin Cancer Res. 2011 Jan 1;17(1):165-73. doi: 10.1158/1078-0432.CCR-10-0565. Epub 2010 Nov 11.


Purpose: To evaluate the clinical relevance of circulating CEACAM5mRNA-positive cells in patients with operable colorectal cancer (CRC).

Methods: Peripheral blood was obtained from 265 patients with operable CRC before the initiation of adjuvant systemic therapy from 96 normal donors and RNA prepared from the Lovo and ARH-77 CRC and leukemic cell lines, respectively, was used as positive and negative controls. The detection of CEACAM5mRNA-positive cells was done using a real-time PCR assay. The association with known prognostic factors and the effect of CEACAM5mRNA-positive cells on patients' prognosis was investigated.

Results: The analytical detection limit of the method was found to correspond to 0.7 Lovo cell equivalence/5 μg RNA, with a sensitivity of 1 tumor cell/10(5) normal cells and a specificity of 97%. Ninety-eight (37%) patients had detectable circulating CEACAM5mRNA-positive cells. Detection of CEACAM5mRNA-positive cells was significantly associated with higher relapse rate (P < 0.001), decreased disease-free survival (DFS; P < 0.001), higher death rate (P = 0.017), and decreased median overall survival (P = 0.025). Multivariate analysis revealed that the detection of circulating CEACAM5mRNA-positive cells was an independent prognostic factor for decreased DFS [HR = 3.4; 95% CI: 2.0-5.9; P < 0.001].

Conclusions: Detection of peripheral blood CEACAM5mRNA-positive cells is an adverse prognostic factor correlated with poor clinical outcome in patients with operable CRC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Carcinoembryonic Antigen / blood
  • Carcinoembryonic Antigen / genetics*
  • Case-Control Studies
  • Colorectal Neoplasms / blood*
  • Colorectal Neoplasms / diagnosis
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / surgery
  • Female
  • Follow-Up Studies
  • GPI-Linked Proteins / blood
  • GPI-Linked Proteins / genetics
  • Humans
  • Male
  • Multivariate Analysis
  • Neoplasm Staging
  • Polymerase Chain Reaction*
  • Prognosis
  • RNA, Messenger / blood
  • RNA, Messenger / genetics*
  • Recurrence
  • Survival Analysis
  • Treatment Outcome


  • CEACAM5 protein, human
  • Carcinoembryonic Antigen
  • GPI-Linked Proteins
  • RNA, Messenger