EPIDERMAL GROWTH-FACTOR RECEPTOR, C-ERBB-2 AND P53 OVEREXPRESSIONS INEPITHELIAL HYPERPLASTIC LESIONS OF THE LARYNX

An immunohistochemical analysis of overexpression of epidermal growth factor receptor (EGFR), c-erbB-2, and p53 proteins was performed on 43 biopsies of laryngeal epithelial hyperplastic lesions (EHLL); classif ied according to the Kambic-Lenart classification, and in 11 cases of laryngeal carcinoma (SCCL). The aim of the present study was to determ ine whether there is a correlation between the staining patterns of th ese proteins and different grades of EHLL, and to reveal their possibl e prognostic value. We compared the staining patterns of atypical hype rplasia adjacent to cancer with the same type of lesions which have no t turned malignant. p53 and EGFR overexpressions were detected in 28/5 4 (52%) and 33/54 cases (61%), respectively, and tend to increase with the degree of epithelial changes. The intensity of staining in variou s grades of EHLL adjacent to cancer was more pronounced than the same type of lesions which have not progressed to cancer. c-erbB-2 was weak ly positive in the majority of cases, and changed from predominantly m embranous in simple hyperplasia to cytoplasmic staining in abnormal an d atypical hyperplasias. There was no significant statistic correlatio n between the amount of positive cells for all proteins and the grade of epithelial abnormalities. We conclude that the overexpression of ea ch biomarker itself adds little predictive value over routine histomor phology, and cannot be regarded as a reliable prognostic factor for EH LL. However, the histologic characteristics of atypical hyperplasia to gether with the immunostaining patterns of EGFR and p53 up to two-thir ds or more of the epithelial thickness could be considered a reliable pattern which correlates with the progression to cancer.