The prognostic role of circulating tumor cells (CTCs) detected by RT-PCR in breast cancer: a meta-analysis of published literature

Breast Cancer Res Treat. 2011 Dec;130(3):809-16. doi: 10.1007/s10549-011-1379-4. Epub 2011 Feb 11.


The prognostic significance of circulating tumor cells (CTCs) in patients with breast cancer is controversial. We performed a meta-analysis of published literature to assess whether the detection of CTCs in patients diagnosed with primary breast cancer can be used as a prognostic factor. We searched Medline, Science Citation Index, and Embase databases as well as reference lists of relevant articles (including review articles) for studies that assessed the prognostic relevance of tumor cell detection in the peripheral blood (PB). A total of 24 eligible studies with 4,013 cases and 1,333 controls were included. Meta-analyses were performed using a random-effects model, using the hazard ratio (HR) and 95% confidence intervals (95% CIs) as effect measures. The positive detection of CTCs in patients was significantly associated with poor overall survival (OS) (HR = 3.00 [95% CI 2.29-3.94], n = 17, P < 0.0001) and recurrence-free survival (RFS) (HR = 2.67 [95% CI 2.09-3.42], n = 22, P < 0.0001). CTC-positive breast cancers were significantly associated with high histological grade (HR = 1.21 [95% CI 1.09-1.35], n = 34, P < 0.0001), tumor size (>2 cm) (HR = 1.12 [95% CI 1.02-1.22], n = 31, P = 0.01). and nodal status (≥1) (HR = 1.10 [95% CI 1.00-1.21], n = 32, P = 0.037), but cytokeratin-19 (CK-19) mRNA-positive CTCs were not associated with these clinicopathological parameters of breast cancer. Furthermore, the presence of CTCs was not associated with estrogen receptor (ER) negativity, progesterone receptor (PR) negativity, or human epidermal growth factor receptor type 2 (HER2) positivity. Detection of CTCs in the PB indicates poor prognosis in patients with primary breast cancer. Larger clinical studies are required to further evaluate the role of these markers in clinical practice.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers, Tumor
  • Breast Neoplasms / diagnosis*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / mortality
  • Female
  • Humans
  • Neoplasm Grading
  • Neoplasm Staging
  • Neoplastic Cells, Circulating / metabolism*
  • Prognosis
  • Publication Bias
  • Reverse Transcriptase Polymerase Chain Reaction*
  • Sensitivity and Specificity


  • Biomarkers, Tumor