Metaplastic breast carcinomas are basal-like tumours

Histopathology. 2006 Jul;49(1):10-21. doi: 10.1111/j.1365-2559.2006.02467.x.


Aims: Recently, an immunohistochemical panel comprising antibodies against HER2, oestrogen receptor (ER), epidermal growth factor receptor (EGFR) and cytokeratin (CK) 5/6 was reported to identify basal-like breast carcinomas, as defined by cDNA microarrays. Our aim was to analyse a series of metaplastic breast carcinomas (MBCs) using this panel plus two other basal markers (CK14 and p63) and progesterone receptor (PR), to define how frequently MBCs show a basal-like immunophenotype.

Methods and results: Sixty-five cases were retrieved from the pathology archives of the authors' institutions and reviewed by three of the authors. Immunohistochemistry with antibodies for HER2, ER, EGFR, CK5/6, CK14 and p63 was performed according to standard methods. All but six cases (91%) showed the typical immunoprofile of basal-like tumours (ER- and HER2-, EGFR+ and/or CK5/6+). When CK14 and p63 were added to the panel, two additional cases could be classified as basal-like. The majority of MBCs lacked PR, except 4/19 (21%) carcinomas with squamous metaplasia.

Conclusions: Our results demonstrate that MBCs show a basal-like phenotype, regardless of the type of metaplastic elements. Moreover, as these neoplasms frequently overexpress EGFR (57%), patients with MBC may benefit from treatment with anti-EGFR drugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers, Tumor / metabolism
  • Breast Neoplasms / classification
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology*
  • ErbB Receptors / metabolism
  • Female
  • Humans
  • Immunohistochemistry
  • Keratins / metabolism
  • Membrane Proteins / metabolism
  • Metaplasia
  • Neoplasms, Basal Cell / classification
  • Neoplasms, Basal Cell / metabolism
  • Neoplasms, Basal Cell / pathology
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism


  • Biomarkers, Tumor
  • CKAP4 protein, human
  • Membrane Proteins
  • Receptors, Estrogen
  • Receptors, Progesterone
  • Keratins
  • ErbB Receptors
  • Receptor, ErbB-2