Molecular markers
EGFR
Authors: Nat Pernick, M.D., Monika Roychowdhury, M.D.
Last author update: 1 June 2005
Last staff update: 21 March 2024
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: EGFR [title]
See Also: EGFR mutation specific antibodies
Cite this page: Pernick N, Roychowdhury M. EGFR. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainsegfr.html. Accessed December 21st, 2024.
Definition / general
- Epidermal Growth Factor Receptor
- Also called HER1, c-erb-B1; on 7p
- Member of epidermal growth factor receptor family (also HER2)
- 170 kDa transmembrane receptor that induces tyrosine kinase activity affecting cell growth
- Activated by epidermal growth factor and transforming growth factor alpha
- Lung adenocarcinoma patients with specific mutations may have clinical response to gefitinib (targets EGFR kinase)
- Brain: amplification is favorable prognostic factor in glioblastoma multiforme (Arch Pathol Lab Med 2005;129:624)
- Breast: 6% of breast carcinomas show EGFR amplification (7 - 18 copies) associated with EGRF protein overexpression but not HER2 status
- Patients may be responsive to EGFR therapy (Mod Pathol 2005;18:1027)
- Colon: present in 60 - 80% of colorectal carcinomas but these tumors lack gene amplification and patients don't respond to gefitinib (Mod Pathol 2005;18:1350)
- Lung: mutations are associated with terminal respiratory unit type adenocarcinoma of lung (Am J Surg Pathol 2005;29:633)
- EGRF tyrosine kinase inhibitors (gefitinib) show rapid clinical response in 10% of lung cancer patients
Clinical features
EGFR expression is associated with these breast cancers:
- Basal-like (BMC Genomics 2007;8:258)
- Metaplastic (76%), carcinomas with squamous differentiation (87%) (Breast Cancer Res 2005;7:R1028, Int J Surg Pathol 2005;13:319)
- ER negative tumors (Pathol Res Pract 1988;183:25, Breast Cancer Res 2008;10:R49)
- Phyllodes tumors (all types, 19%; malignant, 75%) (Lab Invest 2006;86:54)
- Sarcoma NOS (5 of 7) (Am J Surg Pathol 2006;30:450)
- 6% of breast carcinomas show moderate to low level EGFR amplification associated with protein overexpression, and may be responsive to anti-EGFR therapy, currently used for lung cancer patients (Mod Pathol 2005;18:1027)
- EGFR expression is more common in breast tumors in younger and black women
- EGFR expression associated with lower hormone receptor levels, higher proliferation, genomic instability, HER2 overexpression, higher risk of relapse, poor survival (Cancer 2010;116:1234, J Clin Oncol 2007;25:4405)
Molecular / cytogenetics images
Images hosted on other servers:
Malignant phyllodes tumor and EGFR amplification
IHC and CISH
Metaplastic carcinoma: H&E, EGFR and EGFR-CISH
Spindle cell carcinoma: EGFR and HER2 overexpression
Chromogenic in situ hybridization
