Cyclo-oxygenase-2 over-expression in sporadic colorectal carcinoma without lymph node involvement

Aliment Pharmacol Ther. 2003 Oct 1;18(7):731-40. doi: 10.1046/j.1365-2036.2003.01758.x.


Background: Cyclo-oxygenase-2 over-expression has been reported in most advanced human colorectal cancers.

Aims: To assess the prevalence of cyclo-oxygenase-2 over-expression in non-advanced colorectal cancers, to investigate the correlation between cyclo-oxygenase-2 status and tumour clinicopathological features and molecular phenotype, and to determine the impact of cyclo-oxygenase-2 status on long-term clinical outcome.

Methods: Sixty-one patients who had undergone surgery for colorectal cancer without lymph node involvement were evaluated retrospectively. Cyclo-oxygenase-2 expression was determined by immunohistochemistry. The tumour replication error phenotype was assessed by amplification of the two microsatellites, BAT-25 and BAT-26.

Results: Thirty-six tumours were classified as cyclo-oxygenase-2 positive and 25 as cyclo-oxygenase-2 negative. No correlation was found between cyclo-oxygenase-2 over-expression and clinicopathological features or molecular phenotype. Cyclo-oxygenase-2 over-expression was an independent predictor of a poor prognosis. Indeed, the relative risk of tumour recurrence or death for patients with cyclo-oxygenase-2-positive tumours was 2.13 times that of patients with cyclo-oxygenase-2-negative tumours (P=0.008; 95% confidence interval, 1.22-3.73). This difference remained significant when post-operative deaths were censored in the multivariate analysis (P=0.014).

Conclusion: Cyclo-oxygenase-2 over-expression is not associated with tumour phenotype, but is indicative of a poorer clinical outcome in patients with non-advanced colorectal carcinoma.

MeSH terms

  • Aged
  • Colorectal Neoplasms / metabolism*
  • Cyclooxygenase 2
  • DNA, Neoplasm / genetics
  • Disease-Free Survival
  • Female
  • Humans
  • Immunohistochemistry / methods
  • Isoenzymes / metabolism*
  • Male
  • Membrane Proteins
  • Microsatellite Repeats
  • Neoplasm Recurrence, Local / metabolism
  • Phenotype
  • Prognosis
  • Prostaglandin-Endoperoxide Synthases / metabolism*
  • Regression Analysis
  • Retrospective Studies
  • Survival Analysis


  • DNA, Neoplasm
  • Isoenzymes
  • Membrane Proteins
  • Cyclooxygenase 2
  • PTGS2 protein, human
  • Prostaglandin-Endoperoxide Synthases