Immunohistochemical Detection of EGFR in Paraffin-embedded Tumor Tissues

Abstract

S U M M A R YThe epidermal growth factor receptor (EGFR) is highly expressed in a variety of solid malignant tumors and its expression has been correlated with disease progression and poor survival. With the advent of targeted therapies, especially IMC-C225 (Cetuximab), a monoclonal antibody (MAb) directed against the EGFR, there is an increasing interest in immunohistochemistry (IHC)-based EGFR screening methods using paraffin-embedded tumor specimens to select cancer patients eligible for treatment with Cetuximab. With the EGFRpharmDX kit, a complete assay for demonstration of EGFR is now available. Because no information about the preservation of the EGFR under various conditions of fixation is available, we performed a prospective study on a panel of commonly used fixatives to determine optimal tissue preservation protocols. The stability of the epitope on cut tissue sections stored for a period up to 24 month was also tested using material originating from patients with head and neck cancer, non-small-cell lung carcinomas, and colorectal adenocarcinomas. Depending on the fixative used and the time of storage of cut tissue sections, a variation in the determined level of EGFR expression was demonstrated compared with the most optimal fixation procedure.

Immunohistochemical detection of receptor tyrosine kinases c-kit, EGF-R, and PDGF-R in colorectal adenocarcinomas

“…These results obviously do not correlate with data described in literature where positive EGF-R-staining is reported for 25-75% of colorectal carcinomas [11][12][13]. The controversy of immunohistochemical detection of EGF-R is not a new issue and is discussed in a number of studies because it has been recognized that the immunohistochemical detection rates are influenced by a variety of factors including tissue processing and handling, antibodies, and the criteria of scoring [24][25][26][27]. Accordingly, there is a discrepancy concerning the predictive and prognostic value of pretreatment EGF-R staining [28].…”

Epidermal growth factor receptor mutations in non-small cell lung cancer influence downstream Akt, MAPK and Stat3 signaling

“…ConXicting results were discussed and re-evaluated by a panel of three pathologists including the two original pathologists and a third investigator from the Institute of Pathology, University Hospital Bonn. We employed a four-tier scoring system, similar to those used in other EGFR-immunohistochemistry (IHC) studies (Selvaggi et al 2004;Parra et al 2004;Haura et al 2005;Hirsch et al 2003;Atkins et al 2004). For EGFR and phosphotyrosine-EGFR IHC only membrane staining was evaluated: 0 no or undeWned background staining, 1+ weak and discontinuous, 2+ distinct and of moderate intensity, 3+ strong and complete (Fig.…”

Molecular determinants of response to matuzumab in combination with paclitaxel for patients with advanced non-small cell lung cancer

“…Matuzumab (formerly EMD72.000), from Merck KGaA (Darmstadt, Germany), is a humanized monoclonal antibody (31) that binds to the extracellular domain III of EGFR in a region that is nonoverlapping from the cetuximab binding site and inhibits ligand-mediated in vitro kinase activation (20 Immunohistochemistry A reference pathologist (SS) assessed EGFR expression by immunohistochemistry (IHC) in each case prior to study entry. IHC staining of the tumor tissue array samples was performed by using the EGFR pharmDx kit (DakoCytomation, Carpinteria, CA) as previously described (36). Only patients with detectable EGFR expression (minimum of 5% of all tumor cells) were included in the clinical study.…”