Discordance in ERα, PR and HER2 receptor status across different distant breast cancer metastases within the same patient

Ann Oncol. 2013 Dec;24(12):3017-23. doi: 10.1093/annonc/mdt390. Epub 2013 Oct 10.

Abstract

Background: We studied discordance in estrogen receptor alpha (ERα), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status between multiple distant metastases from the same breast cancer patient.

Material and methods: Multiple distant metastases from 55 female patients were stained for ERα, PR and HER2 by immunohistochemistry and in situ hybridization for confirmation of the HER2 status.

Results: Different metastatic sites within the same patient showed discordance in ERα receptor status in 7.3% or 10.9% of patients (using a 10% or 1% threshold for positivity, respectively). For PR, 29.1% or 30.9% of patients showed discordance. Taking ERα and PR together, 36.4% of cases (both thresholds) showed discrepancy between metastases. In 10.9% (10% threshold) or 14.5% of patients (1% threshold), such discordance could have clinical consequences with regard to hormonal treatment. For HER2, there was 3.6% discordance on the immunohistochemical level but 0% on the gene level.

Conclusion: In a significant proportion of metastatic breast cancer patients, discordance in ERα and PR receptor status between different metastatic sites was observed. This implies that multiple metastases may need to be biopsied to optimally reassess receptors.

Keywords: ERα; HER2; PR; breast cancer; immunohistochemistry; multiple metastases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bone Neoplasms / metabolism*
  • Bone Neoplasms / secondary
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Carcinoma, Ductal, Breast / metabolism*
  • Carcinoma, Ductal, Breast / secondary
  • Estrogen Receptor alpha / metabolism*
  • Female
  • Humans
  • Receptor, ErbB-2 / metabolism*
  • Receptors, Progesterone / metabolism*

Substances

  • Estrogen Receptor alpha
  • Receptors, Progesterone
  • estrogen receptor alpha, human
  • ERBB2 protein, human
  • Receptor, ErbB-2