A systematic review to establish the frequency of cyclooxygenase-2 expression in normal breast epithelium, ductal carcinoma in situ, microinvasive carcinoma of the breast and invasive breast cancer

Br J Cancer. 2011 Jun 28;105(1):13-7. doi: 10.1038/bjc.2011.204. Epub 2011 Jun 7.


Background: Epidemiological studies have suggested a protective effect of cyclooxygenase (COX)-inhibiting non-steroidal anti-inflammatory drugs in breast cancer risk and disease progression. We performed a systematic review to evaluate the frequency of COX-2 expression in normal breast epithelium, ductal carcinoma in situ of breast (DCIS), DCIS-adjoining invasive breast cancer, microinvasive carcinoma of the breast (MICB) and invasive breast cancer.

Methods: Literature searches were carried out on MEDLINE, EMBASE and Web of Science from their commencement until September 2010. Primary studies examining COX-2 expression by immunohistochemistry methodology were included. Meta-analyses were carried out using random effects models for individual study estimates of COX-2 expression and pooled to give an overall estimate.

Results: The pooled prevalences (95% confidence intervals) of COX-2 expressions were 53% (44-61) in DCIS studies and 42% (36-49) in the invasive breast cancer studies. There were too few studies involving normal breast epithelium, DCIS-adjoining invasive breast cancer and MICB to conduct meta-analyses.

Conclusion: The findings from our meta-analyses have shown similar COX-2 expression in DCIS and invasive breast cancer. This may suggest the involvement of COX-2 in early carcinogenesis. Further studies of COX-2 expression in DCIS are required to investigate the use of COX-2 as a potential drug target for prevention of disease progression in DCIS.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Biomarkers, Tumor / metabolism*
  • Breast / metabolism*
  • Breast / pathology
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Carcinoma, Ductal, Breast / metabolism*
  • Carcinoma, Ductal, Breast / pathology
  • Carcinoma, Intraductal, Noninfiltrating / metabolism*
  • Carcinoma, Intraductal, Noninfiltrating / pathology
  • Cyclooxygenase 2 / metabolism*
  • Female
  • Humans
  • Meta-Analysis as Topic
  • Neoplasm Invasiveness


  • Biomarkers, Tumor
  • Cyclooxygenase 2
  • PTGS2 protein, human