The transformation of laryngeal leucoplakia to cancer

Abstract

The transformation of laryngeal keratosis to cancer may occur via a progression from normal epithelium to keratosis without cellular atypia, through varying degrees of atypia to the stage of carcinoma-in-situ when the full thickness of the epithelium is occupied by atypical cells until finally, with breaching of the basement membrane, an invasive carcinoma occurs. Although this is, in theory, an attractive sequence, rarely is an alteration in the epithelium from keratosis without atypia to keratosis with atypia found. Furthermore, most of the carcinomas which developed were not in-situ but invasive. Therefore the significant pathway is probably a change from normal nonkeratinizing stratified squamous epithelium via keratosis with atypia to invasive carcinoma. It is important to document keratosis of the larynx as being with or without cellular atypia. Keratosis with atypia should be closely observed because, on the evidence presented, it can be considered pre-cancerous.