An immunohistochemical analysis of p53 protein expression in pre‐malignant and malignant tissues of the oral cavity

This study looks at p53 protein expression in dysplastic and malignant lesions of the oral cavity using an immunohistochemical staining technique. Archival biopsy specimens of oral dysplasia of squamous cell carcinoma from 64 patients were analysed immunohistochemically. Sections from 90 oral biopsy specimens were examined in all. Positive immunohistochemical detection of the p53 protein, demonstrated by brown nuclear staining, was detectable in over 80% of mild, moderate and severe dysplastic tissues as well as carcinoma-in-situ and squamous carcinoma specimens. We concluded that p53 protein expression occurs frequently in both malignant and dysplastic lesions of the oral cavity, suggesting that abnormally detectable p53 protein is present at the very early stages of development of oral squamous carcinoma. Oral cancer may provide a good model for the study of multistage tumorigenesis in head and neck cancer as the lesions are frequently detected at the pre-invasive stage and are accessible to biopsy