AN IMMUNOHISTOCHEMICAL ANALYSIS OF P53 PROTEIN EXPRESSION IN PREMALIGNANT 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 tech nique. Archival biopsy specimens of oral dysplasia of squamous cell ca rcinoma from 64 patients were analysed immunohistochemically. Sections from 90 oral biopsy specimens were examined in all. Positive immunohi stochemical detection of the p53 protein, demonstrated by brown nuclea r staining, was detectable in over 80% of mild, moderate and severe dy splastic tissues as well as carcinoma-in-situ and squamous carcinoma s pecimens. We concluded that p53 protein expression occurs frequently i n both malignant and dysplastic lesions of the oral cavity, suggesting that abnormally detectable p53 protein is present at the very early s tages of development of oral squamous carcinoma. Oral cancer may provi de 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.