title: Immunohistochemical Evaluation of Mast Cells in Leukoplakia and Oral Squamous Cell Carcinoma.
abstract: BACKGROUND
  More than 90% of oral cancers are squamous cell carcinomas with oral leukoplakia being the most common potentially malignant disorder. Among the cell types in the stroma, mast cells play an important role in tumourigenesis through various mechanisms.
  
  
  OBJECTIVE
  The present study was aimed at comparing the mast cell count among normal oral mucosa, leukoplakia and Oral squamous cell carcinoma (OSSC) and to evaluate the possible role of mast cells in carcinogenesis.
  
  
  METHODS
  Mast cell count was assessed immunohistochemically using anti-mast cell tryptase amongst 20 cases of leukoplakia and OSSC each and 10 normal gingival samples. Overall comparison was done using Kruskal Wallis test and intergroup comparison was done using Mann-Whitney U test.
  
  
  RESULTS
  The results of the present study showed an increase in mast cell count from normal oral mucosa (Mean: 7.73) to leukoplakia (Mean: 15.11) to squamous cell carcinoma (Mean: 22.73). Comparison of mean number of mast cells amongst three groups (p-value: 0.001) and intergroup comparisons showed statistical significance.
  
  
  CONCLUSIONS
  Mast cells favour malignant transformation and can be used as indicators of disease progression.
authors.affiliation: Former Postgraduate, Department of Oral Pathology, Faculty of Dental Sciences, Sri Ramachandra University , Porur, Chennai, India .
authors.forename: Saranya
authors.initials: S
authors.lastname: Ramsridhar
authors.affiliation: Professor and Head, Department of Oral Pathology, Faculty of Dental Sciences, Sri Ramachandra University , Porur, Chennai, India .
authors.forename: Malathi
authors.initials: M
authors.lastname: Narasimhan
keywords: Carcinogenesis; Mast cell tryptase; Potentially malignant disorder