Background: The identification of genetic changes in preinvasive epithelial lesions may provide markers for a better assessment of the progression potential.
Materials and methods: p53, MDM2 and PCNA immunophenotypes were examined in 57 cases of squamous cell carcinoma (SCC) of the upper aerodigestive tract and the adjacent normal and dysplastic epithelia.
Results: PCNA index increased with increasing grade of dysplasia. p53 protein was expressed in 35% and MDM2 protein in 33% of SCCs. The p53 protein was expressed in 89% of mild and moderate and in 93% of severe dysplasia and carcinoma in situ adjacent to p53-positive SCCs. The MDM2 protein was expressed in 30% of mild and moderate and in 54% of severe dysplasia and carcinoma in situ adjacent to MDM2-positive SCCs. Preinvasive lesions adjacent to negative SCCs stained negative.
Conclusions: p53 protein was detected more frequently in preinvasive lesions than MDM2 protein and seems to be of greater value as a biomarker.