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Goel S, Batra A, Singhal G, Goel S. To Study the Role of PTEN, EGFR and HER2 in Early Glottic Squamous Cell Carcinoma. Indian J Otolaryngol Head Neck Surg 2023; 75:707-712. [PMID: 37275058 PMCID: PMC10234964 DOI: 10.1007/s12070-022-03455-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/25/2022] [Indexed: 01/09/2023] Open
Abstract
Laryngeal carcinoma is the most common site of malignancy in head and neck region worldwide. Surgical options are limited in cases of laryngeal malignancy and moajority of cases are treated with chemoradiotherapy. Targeted therapy is an evolving novel approach to treat laryngeal carcinoma. The study was conducted to evaluate the role of PTEN, EGF and HER2 in early glottic squamous cell carcinoma cases. 52 samples of early glottis carcoinoma were collected in UCMS and GTB hospital, New Delhi after patients had undergone CO2 laser excision at the centre. Histopathologic and IHC examination was conducted on the specimen for PTEN, EGFR and HER2 molecules. PTEN was negative in 82.69% cases compared to the stroma with three year local control rate of 72.09%. EGFR was positive in 67.31% samples with three year local control rate of 68.57%. HER2 was negative in all the samples. PTEN and EGFR can be used as prognostic markers as well as novel agents for targeted therapy in the future.
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Affiliation(s)
- Sachin Goel
- Department of ENT, ABVIMS & Dr RML Hospital, New Delhi, India
| | - Ankur Batra
- Department of ENT, Royal Hmapshire County Hospital, Winchester, UK
| | - Gaurang Singhal
- Department of pathology, Action Care hospital, New Delhi, India
| | - Snigdha Goel
- Department of ENT, ABVIMS and Dr. Ram Manohar Lohia hospital, New Delhi, India
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Varun C, Dineshkumar T, Jayant VS, Rameshkumar A, Rajkumar K, Rajashree P, Mathew J, Arunvignesh RK. Salivary Her2/neu Levels in Differentiation of Oral Premalignant Disorders and Oral Squamous Cell Carcinomas. Asian Pac J Cancer Prev 2015; 16:5773-7. [DOI: 10.7314/apjcp.2015.16.14.5773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Zhang J, Saba NF, Chen GZ, Shin DM. Targeting HER (ERBB) signaling in head and neck cancer: An essential update. Mol Aspects Med 2015; 45:74-86. [PMID: 26163475 DOI: 10.1016/j.mam.2015.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 07/01/2015] [Accepted: 07/01/2015] [Indexed: 12/13/2022]
Abstract
HNC (head and neck cancer) remains the 6th most common carcinoma worldwide. The suboptimal survival and toxicities observed with conventional approaches warrant exploration of novel therapeutic strategies such as targeted therapies. Although targeting EGFR (epidermal growth factor receptor) with cetuximab demonstrated clinical promise, HER (human epidermal growth factor receptor) or ERBB (erythroblastic leukemia viral oncogene homolog) targeted therapy in HNC has overall been suboptimal to date in clinical settings. Overcoming the resistance as well as identifying new strategies therefore remains a significant challenge. In this review, we will discuss the emerging roles of HER members besides EGFR. A comprehensive "three-dimensional" view of HER signaling pathway from the importance of EGFR nuclear translocation to our maturing concept of receptors' "spatial regulation", as well as the interdependence and interaction among different HER members will also be addressed to complete an essential update of HER signaling in HNC.
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Affiliation(s)
- Jun Zhang
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, NE, Atlanta, GA 30322, USA; Department of Internal Medicine, Division of Hematology, Oncology and Blood & Marrow Transplantation, Holden Comprehensive Cancer Center, University of Iowa Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USA
| | - Nabil F Saba
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, NE, Atlanta, GA 30322, USA
| | - Georgia Zhuo Chen
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, NE, Atlanta, GA 30322, USA
| | - Dong M Shin
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, NE, Atlanta, GA 30322, USA.
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HER2/neu: an increasingly important therapeutic target. Part 2: Distribution of HER2/neu overexpression and gene amplification by organ, tumor site and histology. ACTA ACUST UNITED AC 2014. [DOI: 10.4155/cli.14.62] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Monteiro LS, Diniz-Freitas M, Garcia-Caballero T, Warnakulasuriya S, Forteza J, Fraga M. Combined cytoplasmic and membranous EGFR and p53 overexpression is a poor prognostic marker in early stage oral squamous cell carcinoma. J Oral Pathol Med 2012; 41:559-67. [PMID: 22417132 DOI: 10.1111/j.1600-0714.2012.01142.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Our aim was to evaluate the expression of several molecules that regulate growth, the cell cycle and signalling pathways including EGFR, p53, p16 and p27 in oral squamous cell carcinomas (OSCC). We examined their utility as prognostic markers by relating to clinicopathological characteristics and the clinical outcome. PATIENTS AND METHODS Using tissue microarray technology, we analysed 67 primary OSCC and examined immunohistochemical expression of EGFR, p53, p16 and p27. Multivariate analysis was conducted to examine their role in survival. RESULTS Many of the markers were highly expressed in these cancers. Membranous EGFR expression in 95.2%, both membrane and cytoplasm expression in 35%, p53 expression in 61.6%, p27 expression in 89.5% and p16 expression in 27.9% of cases. In the multivariate analysis, independent prognostic influence of a lower overall survival was determined only for advanced tumour stage (P < 0.001), p53 overexpression (P = 0.004), EGFR cytoplasm and membrane co-expression location (P = 0.002) and p16 reduced expression (P = 0.002). When considering a subgroup of early stage tumours, p53 overexpression (P = 0.028) and combined membranous and cytoplasm EGFR co-expression (P = 0.039) were indicators of a lower overall survival. For disease-free survival, in addition to these three factors, the histological grade (P = 0.011) showed independent prognostic values. CONCLUSION The independent value of EGFR subcellular location (cytoplasm and membrane) and p53 overexpression in overall survival even in early stages of OSCC suggests that these markers may serve as reliable biological markers to identify high-risk subgroups and to guide therapy.
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Affiliation(s)
- Luís Silva Monteiro
- Medicine and Oral Surgery Department, Dental Sciences Group-Health Sciences Research Centre, Instituto Superior de Ciências da Saúde Norte, Paredes, Portugal.
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Monteiro LS, Diniz-Freitas M, Garcia-Caballero T, Forteza J, Fraga M. EGFR and Ki-67 expression in oral squamous cell carcinoma using tissue microarray technology. J Oral Pathol Med 2010; 39:571-8. [PMID: 20202087 DOI: 10.1111/j.1600-0714.2009.00876.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Our aim was to validate the use of tissue microarrays (TMA) in oral squamous cell carcinomas (OSCC) to analyse epidermal growth factor receptor (EGFR) and Ki-67 expression. We also analysed the relationship that the expression of these markers may have with clinical, pathological and survival variables. PATIENTS AND METHODS The study sample comprised 39 unselected patients diagnosed and treated for OSCC. We analysed Ki-67 and EGFR expression by immunohistochemistry on formalin-fixed, paraffin-embedded surgical specimens. Whole sections (WS) were compared with double 1.5 mm core-tissue microarrays. RESULTS High EGFR expression was observed both on TMA (in 98% of the cases) and WS (in 100% of the cases) with substantial agreement kappa value (0.720). EGFR expression was not significantly associated with clinical, pathological and survival variables on TMA and WS. Ki-67 analysis showed a Spearman correlation of 0.741 with a Ki-67 mean labelling index of 45% in TMA and 56.8% in WS. We found a significant relationship between gender and Ki-67 labelling index on WS (P = 0.022) and TMA (P = 0.002). Clinical stage was the only parameter in multivariate analysis that had a significant predictive value. CONCLUSION We demonstrate that dual 1.5 mm core TMA is a valid, rapid, economical and tissue-saving way to study OSCC biopsies and that it presents strong correlation with the WS. EGFR overexpression in OSCC suggests that these tumours may be a candidate for therapy investigation directed to EGFR.
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Affiliation(s)
- Luís Silva Monteiro
- Department of Oral Surgery and Oral Medicine, Higher Institute of Health Sciences, Paredes, Portugal.
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Ali MALS, Gunduz M, Gunduz E, Tamamura R, Beder LB, Katase N, Hatipoglu OF, Fukushima K, Yamanaka N, Shimizu K, Nagatsuka H. Expression and Mutation Analysis of Her2 in Head and Neck Squamous Cell Carcinoma. Cancer Invest 2009; 28:495-500. [DOI: 10.3109/07357900903476778] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Her-2 immunohistochemical expression in oral squamous cell carcinomas is associated with polysomy of chromosome 17, not Her-2 amplification. Head Neck Pathol 2009; 3:263-70. [PMID: 20596843 PMCID: PMC2811573 DOI: 10.1007/s12105-009-0134-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 07/27/2009] [Indexed: 10/20/2022]
Abstract
Based on the prognostic role of Her-2 amplification and protein overexpression in breast cancer, various studies have been performed in oral squamous cell carcinomas (OSCC) with inconsistent results. As in invasive breast carcinomas Her-2 overexpression has been related to an increased number of chromosome 17 copies, a common chromosomal alteration in OSCC, we evaluated the association between polysomy 17 and Her-2 protein expression in a series of primary OSCC. Forty-one incisional biopsies of primary OSCC were included in the study. Protein expression was evaluated immunochistochemically with CB11 mouse monoclonal anti-human antibody. The reaction was arbitrarily characterized as absent, faint, moderate, and strong, and staining pattern as cytoplasmic and membranous. Positive cases were analyzed by chromogenic in situ hybridisation (CISH) to access Her-2 status. The association between polysomy 17 and Her-2 expression was checked by Fisher's exact test. Four cases were negative and 37 cases were positive for Her-2. Staining was faint in 15 cases and moderate in 22 cases. CISH showed that all cases with faint staining were diploid, while from the cases with moderate staining 10 were diploid and 12 polysomic for chromosome 17. Thirteen cases showed purely cytoplasmic staining, while in 24 there were areas of both cytoplasmic and membranous staining. There was a statistically significant correlation between intensity of the reaction and polysomy 17 (P = 0.0036), in particular for cases with both cytoplasmic and membranous staining (P = 0.0128). In some OSCC Her-2 immunohistochemical expression may be associated with chromosome 17 polysomy and not Her-2 amplification.
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Ratushny V, Astsaturov I, Burtness BA, Golemis EA, Silverman JS. Targeting EGFR resistance networks in head and neck cancer. Cell Signal 2009; 21:1255-68. [PMID: 19258037 PMCID: PMC2770888 DOI: 10.1016/j.cellsig.2009.02.021] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2009] [Accepted: 02/17/2009] [Indexed: 01/01/2023]
Abstract
A core set of oncoproteins is overexpressed or functionally activated in many types of cancer, and members of this group have attracted significant interest as subjects for development of targeted therapeutics. For some oncoproteins such as EGFR/ErbB1, both small molecule and antibody agents have been developed and applied in the clinic for over a decade. Analysis of clinical outcomes has revealed an initially unexpected complexity in the response of patients to these agents. Diverse factors, including developmental lineage of the tumor progenitor cell, co-mutation or epigenetic modulation of genes encoding proteins in an extended EGFR signaling network or regulating core survival responses in individual tumors, and environmental factors including inflammatory agents and viral infection, all have been identified as modulating response to treatment with EGFR-targeted drugs. Second and third generation therapeutic strategies increasingly incorporate knowledge of cancer type-specific signaling environments, in a more personalized treatment approach. This review takes squamous cell carcinoma of the head and neck (SCCHN) as a specific example of an EGFR-involved cancer with idiosyncratic biological features that influence design of treatment modalities, with particular emphasis on commonalities and differences with other cancer types.
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Affiliation(s)
- Vladimir Ratushny
- Programs in Head and Neck Cancer and Molecular Medicine, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
- Program in Molecular and Cell Biology and Genetics, Drexel University College of Medicine, 2900 W. Queen Lane, Philadelphia, PA 19129
| | - Igor Astsaturov
- Programs in Head and Neck Cancer and Molecular Medicine, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
- Department of Medical Oncology, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
| | - Barbara A. Burtness
- Programs in Head and Neck Cancer and Molecular Medicine, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
- Department of Medical Oncology, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
| | - Erica A. Golemis
- Programs in Head and Neck Cancer and Molecular Medicine, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
| | - Joshua S. Silverman
- Programs in Head and Neck Cancer and Molecular Medicine, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
- Department of Radiation Oncology, Fox Chase Cancer Center, 333 Cottman Ave., Philadelphia, PA, 19111, USA
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Monteiro LS, Bento MJ, Palmeira C, Lopes C. Epidermal growth factor receptor immunoexpression evaluation in malignant salivary gland tumours. J Oral Pathol Med 2009; 38:508-13. [DOI: 10.1111/j.1600-0714.2009.00770.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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ErbB receptors in the biology and pathology of the aerodigestive tract. Exp Cell Res 2008; 315:572-82. [PMID: 18778701 DOI: 10.1016/j.yexcr.2008.08.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 08/12/2008] [Accepted: 08/12/2008] [Indexed: 01/02/2023]
Abstract
The most common sites of malignancies in the aerodigestive tract include the lung, head and neck and the esophagus. Esophageal adenocarcinomas (EA), esophageal squamous cell carcinomas (ESCC), and squamous cell carcinomas of the head and neck (SCCHN) are the primary focus of this review. Traditional treatment for aerodigestive tract cancers includes primary chemoradiotherapy (CRT) or surgical resection followed by radiation (or CRT). Recent developments in treatment have focused increasingly on molecular targeting strategies including cetuximab (a monoclonal antibody against epidermal growth factor receptor (EGFR)). Cetuximab was FDA approved in 2006 for treatment of SCCHN, underscoring the importance of understanding the biology of these malignancies. EGFR is a member of the ErbB family of growth factor receptor tyrosine kinases. The major pathways activated by ErbB receptors include Ras/Raf/MAPK; PI3K/AKT; PLCgamma and STATs, all of which lead to the transcription of target genes that may contribute to aerodigestive tumor progression. This review explores the expression of ErbB receptors in EA, ESCC and SCCHN and the signaling pathways of EGFR in SCCHN.
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Wei Q, Sheng L, Shui Y, Hu Q, Nordgren H, Carlsson J. EGFR, HER2, and HER3 expression in laryngeal primary tumors and corresponding metastases. Ann Surg Oncol 2008; 15:1193-201. [PMID: 18172732 DOI: 10.1245/s10434-007-9771-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 11/22/2007] [Accepted: 11/26/2007] [Indexed: 12/21/2022]
Abstract
BACKGROUND There are several substances available to target members of the epidermal growth factor receptor (EGFR) family, both for imaging in nuclear medicine and for various forms of therapy. The level and stability of expression in both primary tumors and corresponding metastases is crucial in the assessment of a receptor as a target in systemic tumor therapy. To date, the expression of EGFR family members has only been determined in primary laryngeal carcinomas, and we have not found published data regarding the receptor status in corresponding metastatic lesions. METHODS Expression of EGFR, HER2, and HER3 was investigated immunohistochemically in both lymph node metastases and corresponding primary laryngeal squamous carcinomas (n = 40). RESULTS EGFR overexpression (2+ or 3+) was found in 87.5% (35/40) of the laryngeal primary tumors and 82.5% (33/40) of the corresponding lymph node metastases. There was a good agreement between the primary tumors and the paired metastases regarding EGFR expression. HER2 overexpression was found in only four cases (10.5%) of the studied primary tumors and in all cases the HER2 expression was retained in the paired metastases. Another two metastases gained HER2 status when compared to the corresponding primary tumors. Strong HER3 staining was found in 26.7% of both the primary tumors and the corresponding metastases. CONCLUSIONS The high frequency and stability in EGFR expression is encouraging for efforts to use EGFR targeting agents (e.g. Iressa, Tarceva, Erbitux or radiolabeled antibodies) for therapy of laryngeal carcinoma. For a few laryngeal carcinoma patients with HER2 overexpression, anti-HER2 agents could possibly be used.
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Affiliation(s)
- Qichun Wei
- Department of Radiation Oncology, The Second Affiliated Hospital, and Cancer Institute, Zhejiang University School of Medicine, Jiefang Road 88, Hangzhou, 310009, PR China.
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Angiero F, Sordo RD, Dessy E, Rossi E, Berenzi A, Stefani M, Sidoni A. Comparative analysis of c-erbB-2 (HER-2/neu) in squamous cell carcinoma of the tongue: does over-expression exist? And what is its correlation with traditional diagnostic parameters? J Oral Pathol Med 2007; 37:145-50. [DOI: 10.1111/j.1600-0714.2007.00603.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Diniz-Freitas M, García-Caballero T, Antúnez-López J, Gándara-Rey JM, García-García A. Pharmacodiagnostic evaluation of EGFR expression in oral squamous cell carcinoma. Oral Dis 2007; 13:285-90. [PMID: 17448210 DOI: 10.1111/j.1601-0825.2006.01280.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To determine epidermal growth factor receptor (EGFR) expression in oral squamous cell carcinomas (OSCC), and its possible relationships with clinical findings, histological findings, disease course and prognosis. MATERIALS AND METHODS Surgical specimens of 47 OSCCs were studied immunohistochemically for detection of EGFR using a standardized immunohistochemical detection system (EGFR PharmaDx kit). Statistical analysis was used to investigate possible relationships between EGFR expression and clinical findings, histological findings, cell proliferation (MIB1 labelling index), disease course and patient survival. RESULTS Epidermal growth factor receptor expression was absent or weak in 12 cases (25.5%) and moderate or intense in 35 cases (74.5%). However, EGFR expression did not show statistically significant associations with any of the clinical, histological, biological or prognostic variables considered. CONCLUSION First, despite previous suggestions that EGFR is a useful indicator of biological tumour behaviour, the present results suggest that EGFR is not a useful indicator of prognosis in OSCC. Secondly, the high prevalence of EGFR overexpression suggests that the possibility of anti-EGFR therapy in OSCC merits further investigation.
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Affiliation(s)
- M Diniz-Freitas
- Oral Surgery Department, School of Dentistry, Santiago de Compostela, Spain.
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Abstract
Epidermal growth factor receptor (EGFR) is overexpressed in several epithelial malignancies, including head and neck squamous cell carcinoma (HNSCC), which exhibits EGFR overexpression in up to 90% of tumors. EGFR ligands such as transforming growth factor alpha are also overexpressed in HNSCC. EGFR plays a critical role in HNSCC growth, invasion, metastasis and angiogenesis. However, EGFR inhibitors as monotherapy have yielded only modest clinical outcomes. Potential mechanisms for lack of response to EGFR inhibition in HNSCC include constitutive activation of signaling pathways independent of EGFR, as well as genetic aberrations causing dysregulation of the cell cycle. EGFR-directed therapy may be optimized by identifying and selecting those HNSCC patients most likely to benefit from EGFR inhibition. Resistance to EGFR inhibition may be circumvented by combination therapy employing EGFR inhibitors together with other treatment modalities.
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Affiliation(s)
- Shailaja Kalyankrishna
- Department of Otolaryngology, University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Dei Tos AP, Ellis I. Assessing epidermal growth factor receptor expression in tumours: What is the value of current test methods? Eur J Cancer 2005; 41:1383-92. [PMID: 15919198 DOI: 10.1016/j.ejca.2005.03.018] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Accepted: 03/15/2005] [Indexed: 12/20/2022]
Abstract
Over-expression of the epidermal growth factor receptor (EGFR) in tumours is associated with aggressive disease and poor clinical prognosis. In theory, the EGFR status of a tumour provides an indication of the likelihood of response to EGFR-targeted therapy. However, the clinical data do not support a relationship between EGFR expression and response to EGFR-targeted therapies cetuximab, gefitinib and erlotinib. Recently, patients who appear to lack EGFR expression have been shown to respond to cetuximab. Possible causes for this paradox include false negative results due to a lack of sensitivity in the detection system, heterogeneity of EGFR expression within the tumour and specific mutations that mediate response to the tyrosine kinase inhibitors. Immunohistochemistry is the most reliable assay for EGFR expression but its interpretation is confounded by the lack of non-standard techniques. Other approaches for measuring EGFR expression can be considered at best exploratory at this point. Further work is needed to identify how EGFR contributes to carcinogenic and metastatic processes. As tumours that appear to be EGFR negative can respond to cetuximab, there is some doubt as to the usefulness of immunohistochemistry as a screen to select patients for treatment. Histopathology will continue to be essential for unravelling the role of this enigmatic molecule and refining its status as a legitimate target in cancer therapy.
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Affiliation(s)
- A P Dei Tos
- Department of Pathology, Regional Hospital of Treviso, Italy.
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