Estrogen-Receptor, Progesterone-Receptor and HER2 Status Determination in Invasive Breast Cancer. Concordance between Immuno-Histochemistry and MapQuant™ Microarray Based Assay

PLoS One. 2016 Feb 1;11(2):e0146474. doi: 10.1371/journal.pone.0146474. eCollection 2016.

Abstract

Background: Hormone receptor status and HER2 status are of critical interest in determining the prognosis of breast cancer patients. Their status is routinely assessed by immunohistochemistry (IHC). However, it is subject to intra-laboratory and inter-laboratory variability. The aim of our study was to compare the estrogen receptor, progesterone receptor and HER2 status as determined by the MapQuant™ test to the routine immuno-histochemical tests in early stage invasive breast cancer in a large comprehensive cancer center.

Patients and methods: We retrospectively studied 163 invasive early-stage breast carcinoma with standard IHC status. The genomic status was determined using the MapQuant™ test providing the genomic grade index.

Results: We found only 4 tumours out of 161 (2.5%) with discrepant IHC and genomic results concerning ER status. The concordance rate between the two methods was 97.5% and the Cohen's Kappa coefficient was 0.89. Comparison between the MapQuant™ PR status and the PR IHC status gave more discrepancies. The concordance rate between the two methods was 91.4% and the Cohen's Kappa coefficient was 0.74. The HER2 MapQuant™ test was classified as « undetermined » in 2 out of 163 cases (1.2%). One HER2 IHC-negative tumour was found positive with a high HER2 MapQuant™ genomic score. The concordance rate between the two methods was 99.3% and the Cohen's Kappa coefficient was 0.86.

Conclusion: Our results show that the MapQuant™ assay, based on mRNA expression assay, provides an objective and quantitative assessment of Estrogen receptor, Progesterone receptor and HER2 status in invasive breast cancer.

MeSH terms

  • Adult
  • Aged
  • Biological Assay
  • Breast Neoplasms / classification
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Clinical Decision-Making
  • Female
  • Genome, Human
  • Humans
  • Immunohistochemistry
  • Microarray Analysis
  • Middle Aged
  • Neoplasm Invasiveness
  • Neoplasm Staging
  • Receptor, ErbB-2 / metabolism*
  • Receptors, Estrogen / metabolism*
  • Receptors, Progesterone / metabolism*

Substances

  • Receptors, Estrogen
  • Receptors, Progesterone
  • Receptor, ErbB-2

Grants and funding

The authors received no specific funding for this work. Authors SC and HP are employed by QIAGEN. QIAGEN provided support in the form of research material (Affymetrix arrays) and salaries for authors SC and HP, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.