RESUMO
In benign hyperproliferative epidermal diseases(eq. warts, psoriasis) and squamous carcinoma, some molecular markers of hyperproliferative keratinocyte such as cytokeratin 16 and PCNA were expressed predominantly. However, all healthy epidermis including the meatal epidermis are nonreactive to those molecular markers except some of thick skin. Recently, there are several reports which show unusal proliferative capacity around the annular region of the ear drum. Our study has concentrated on the characteristics of the differentiation in healthy deep meatal epidermis using immunohistochemistry with cytokeratins and PCNA. Our investigation has demonstrated that the deep meatal epidermis around the annular region in contrast to the other region of the meatus exhibited unusal proliferative capacity. This result suggests a pathology link such as invasion mechanism and hyperkeratinization between the cholesteatoma and deep meatal skin.