Physiopathology of the cholesteatoma originated from a retraction pocket

Abstract

Cholesteatoma is a cystic structure delimited by stratified epithelium keratinized with expansive growth. They are classified according to their origin as congenital and acquired. Cholesteatomas originated from a retraction pocket belong to this last group. The pathogenesis of its formation is multifactorial. It begins with the formation of a retractable pocket in which disfunction of the Eustachian tube and majoritarily the pneumatization of the mastoid, participate. Numerous theories have tried to explain the transition from this retractable pocket to the appearance of the cholesteatoma. Sudoff et al, by combining the theory of invagination and that of the basal cells solves this problem in part. However, it maintains interrogations such as the mechanisms that start the cellular migration and cellular proliferation. This is the knowledge barrier to this date. Numerous hypothesis have tried to solve this question, among them, the hypothesis that atypical infections such as biofilms or infection due to C pneumoniae as agents involved in the genesis of the cholesteatomas originated from retraction pockets. In this line of investigation several new concepts have risen as the use of MIB1 and MIF for potential use to predict the aggressiveness and recurrency of the cholesteatomas. However, until now the presence of atypical infections has only been found in cholesteatomas, but no investigation line has appeared correlating them to an increase in cellular activity, in order to relate them casually to a higher clinical aggressiveness. In this sense, the Chilean Society of Otolaryngology has recently granted financing for an investigation program that will seek to correlate the presence of infection by C pneumoniae and a higher clinical and molecular aggressiveness of the cholesteatomas, measured by MIB1. This way we expect to obtain more information in order to understand this challenging disease.