Epidermal Growth Factor Receptor and K-RAS status in two cohorts of squamous cell carcinomas

• Published in: BMC cancer Vol. 10; no. 1; p. 189
• Main Authors: Van Damme, Nancy, Deron, Philippe, Van Roy, Nadine, Demetter, Pieter, Bols, Alain, Dorpe, Jo Van, Baert, Filip, Van Laethem, Jean-Luc, Speleman, Franki, Pauwels, Patrick, Peeters, Marc
• Format: Journal Article
• Language: English
• Published: London BioMed Central 11.05.2010; BioMed Central Ltd; BMC
• Subjects: Adult; Aged; Aged, 80 and over; Anal Canal - chemistry; Anal Canal - pathology; Anus Neoplasms - genetics; Anus Neoplasms - metabolism; Anus Neoplasms - pathology; Base Sequence; Belgium; Biomarkers, Tumor - analysis; Biomarkers, Tumor - genetics; Biomedical and Life Sciences; Biomedicine; Canals; Cancer Research; Cancer therapies; Carcinoma, Squamous Cell - genetics; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - pathology; Care and treatment; Cohort Studies; DNA Mutational Analysis; Exons; Female; Gene Amplification; Gene mutations; Genetic aspects; Growth factor receptors; Health aspects; Health Promotion and Disease Prevention; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Male; Medicine/Public Health; Middle Aged; Molecular Sequence Data; Mutation; Oncology; Pathology; Physiological aspects; Polymerase Chain Reaction; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins p21(ras); Ras genes; ras Proteins - genetics; Receptor, Epidermal Growth Factor - analysis; Receptor, Epidermal Growth Factor - genetics; Research Article; Risk factors; Skin cancer; Squamous cell carcinoma; Surgical Oncology; Tonsillar Neoplasms - genetics; Tonsillar Neoplasms - metabolism; Tonsillar Neoplasms - pathology; Tumors; Belgium; Epidermal Growth Factor Receptor; Epidermal Growth Factor Receptor Mutation; Anal Canal; Epidermal Growth Factor Receptor Expression; Epidermal Growth Factor Receptor Gene
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/1471-2407-10-189

Background With the availability of effective anti-EGFR therapies for various solid malignancies, such as non-cell small lung cancer, colorectal cancer and squamous cell carcinoma of the head and neck, the knowledge of EGFR and K-RAS status becomes clinically important. The aim of this study was to analyse EGFR expression, EGFR gene copy number and EGFR and K-RAS mutations in two cohorts of squamous cell carcinomas, specifically anal canal and tonsil carcinomas. Methods Formalin fixed, paraffin-embedded tissues from anal and tonsil carcinoma were used. EGFR protein expression and EGFR gene copy number were analysed by means of immunohistochemistry and fluorescence in situ hybridisation. The somatic status of the EGFR gene was investigated by PCR using primers specific for exons 18 through 21. For the K-RAS gene, PCR was performed using exon 2 specific primers. Results EGFR immunoreactivity was present in 36/43 (83.7%) of anal canal and in 20/24 (83.3%) of tonsil squamous cell carcinomas. EGFR amplification was absent in anal canal tumours (0/23), but could be identified in 4 of 24 tonsil tumours. From 38 anal canal specimens, 26 specimens were successfully analysed for exon 18, 30 for exon 19, 34 for exon 20 and 30 for exon 21. No EGFR mutations were found in the investigated samples. Thirty samples were sequenced for K-RAS exon 2 and no mutation was identified. From 24 tonsil specimens, 22 were successfully analysed for exon 18 and all 24 specimens for exon 19, 20 and 21. No EGFR mutations were found. Twenty-two samples were sequenced for K-RAS exon 2 and one mutation c.53C > A was identified. Conclusion EGFR mutations were absent from squamous cell carcinoma of the anus and tonsils, but EGFR protein expression was detected in the majority of the cases. EGFR amplification was seen in tonsil but not in anal canal carcinomas. In our investigated panel, only one mutation in the K-RAS gene of a tonsil squamous cell carcinoma was identified. This indicates that EGFR and K-RAS mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in anal canal and tonsil squamous cell carcinoma.