title: Evaluation of the epidermal growth factor receptor (EGFR) in colorectal tumours and lymph node metastases.
abstract: Overexpression of the epidermal growth factor receptor (EGFR) often correlates with an aggressive tumour phenotype and poor prognosis. To examine the relevance of EGFR in colorectal cancer, we determined the expression of EGFR protein in 249 colorectal adenocarcinomas and 42 lymph node metastases using immunohistochemistry. Moreover, we investigated a (CA)(n) dinucleotide repeat polymorphism of the EGFR gene in a subset of 114 tumours. High levels of EGFR protein were observed in 123/249 (49.4%) samples. EGFR expression in colorectal carcinomas correlated with differentiation grade (P=0.014). However, there were no associations with Dukes' stage, site, patient age or gender. EGFR protein expression did not influence survival in this colorectal cancer patient cohort (P>or=0.05). Expression was not identical in paired colorectal tumours and lymph node metastases, with only 17/42 (40.5%) samples showing equivalent EGFR levels (P>0.05). The distribution of the (CA)(n) dinucleotide repeat alleles in colorectal adenocarcinomas was not associated with EGFR protein expression (P>0.05). These results indicate that while EGFR overexpression is a common event in colorectal carcinogenesis, it does not influence patient prognosis.
authors.affiliation: Department of Medicine and Therapeutics, University of Aberdeen, Foresterhill, AB25 2ZD, Aberdeen, UK.
authors.forename: J A
authors.initials: JA
authors.lastname: McKay
authors.forename: L J
authors.initials: LJ
authors.lastname: Murray
authors.forename: S
authors.initials: S
authors.lastname: Curran
authors.forename: V G
authors.initials: VG
authors.lastname: Ross
authors.forename: C
authors.initials: C
authors.lastname: Clark
authors.forename: G I
authors.initials: GI
authors.lastname: Murray
authors.forename: J
authors.initials: J
authors.lastname: Cassidy
authors.forename: H L
authors.initials: HL
authors.lastname: McLeod
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism*; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism*; D018900:Dinucleotide Repeats / Q000235:genetics; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008207:Lymphatic Metastasis; D008297:Male; D009363:Neoplasm Proteins / Q000378:metabolism*; D011110:Polymorphism, Genetic; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D009363:Neoplasm Proteins; D066246:ErbB Receptors