Mast cells are increased in leukoplakia, oral submucous fibrosis, oral lichen planus and oral squamous cell carcinoma

Abstract

Introduction: Oral leukoplakia, submucous fibrosis (OSMF), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) are the commonly occurring oral diseases, with characteristic clinical and histological features. These diseases at some stage are associated with chronic inflammation in adjacent connective tissue. Mast cells are the local residents of the connective tissue, and are said to be pro-inflammatory, immunoamplifying in action and producing mitogenic cytokines. These functions of mast cells may play a significant role in the pathogenesis of other oral diseases. Aims: This study was done to histologically evaluate the number of mast cells in tissue sections of oral leukoplakia, submucous fibrosis, lichen planus and squamous cell carcinoma. Materials and Methods: Five cases each of normal oral mucosa, oral leukoplakia, oral submucous fibrosis, lichen planus and squamous cell carcinoma were studied for mast cell number using 1% Toluidine blue. Results: Increase in mast cell number were seen in all the four above mentioned oral diseases, with the highest mast cell count obtained in oral lichen planus. The mast cell number/sq.mm in oral leukoplakia, submucous fibrosis, lichen planus, squamous cell carcinoma were; 59.50, 48.25, 59.75 and 56.75 respectively. Conclusion: As compared to normal oral mucosa, increase in the mast cell number was noted in all the four conditions. Mast cell hyperplasia in oral leukoplakia, OSMF, OLP, OSCC suggests their probable role in the pathogenesis of these diseases.