Oral submucous fibrosis: Histopathological features with pathophysiologic correlations

Abstract

Oral submucous fibrosis (OSMF) is a potentially malignant disorder characterized by juxtaepithelial inflammation and progressive fibrosis of submucosal tissues. It may affect any part of the oral cavity, as well as pharynx and oesophagus. The pathogenesis of OSMF may be attributable to habitual chewing of areca nut and its products, which is more prevalent amongst young population of South East Asia and India. Various histopathological features in different tissue components- epithelial, connective tissue stroma, muscle and salivary gland may be observed along the course of this chronic disorder. In connective tissue, extensive fibrosis with progressive hyalinization of collagen fibers and muscles accompanied by inflammatory response is considered to be pathognomonic feature. Advanced stages of OSMF may show atrophic changes or even dysplasia in the epithelium which may undergo malignant transformation. Malignant transformation rate of OSMF has been proved to be around 7.5%. Thus, identification of early histopathological changes in OSMF can lead to improved survival rates. The present article illustrates the various histopathological features observed during different stages of development of OSMF. A better understanding of the correlation between histopathological features and corresponding clinical manifestations can aid dental surgeons in prognostication of the lesion and determining response to treatment.