title: Expression of Ki-67 in normal oral epithelium, leukoplakic oral epithelium and oral squamous cell carcinoma.
abstract: OBJECTIVE
  To demonstrate the presence, location and pattern of cell proliferation in different histological grades of oral epithelial dysplasia (OED), oral squamous cell carcinoma (OSCC) and normal oral epithelium (NOE) using an antibody directed against the Ki-67 antigen and its intensity of staining evaluated respectively.
  
  
  METHODS
  A total number of 100 archival paraffin embedded blocks obtained from Department of Oral and Maxillofacial Pathology were studied. The case details were retrieved which consisted of histopathologically diagnosed cases of OSCC (n = 20), low risk OED (n = 30), high risk OED (n = 30) and normal appearing mucosa (n = 20) were taken as standard for comparison. Ki-67 immunostaining was detected. Ki-67 positive cells were counted in the five random high power fields in each case.
  
  
  RESULTS
  Ki-67 labeling Index (LI) was restricted to the basal and parabasal layers of the normal oral epithelium irrespective of age, sex and site whereas it was seen in the basal, suprabasal and spinous layers in OED. Ki-67 LI is increased in high risk cases than the low risk cases of OED. Ki-67 positive cells in OSCC were located in the periphery of the tumor nests than the center, where frequent mitoses were observed.
  
  
  CONCLUSIONS
  The architectural alteration evaluated by Ki-67 antibody in proliferating cell distribution in the layers of epithelial dysplasias may provide useful information to evaluate the grading of OED. Ki-67 LI increased in high risk cases than low risk cases of OED. This study showed that over expression of Ki-67 antigen between well-differentiated and poorly differentiated OSCC was in accordance with histologic grade of malignancy but not in accordance with moderately differentiated OSCC.
authors.affiliation: Department of Oral Pathology and Microbiology, Vishnu Dental College and Hospital, Vishnupur, Bhimavaram, Andhra Pradesh, India.
authors.forename: Smita Shrishail
authors.initials: SS
authors.lastname: Birajdar
authors.affiliation: Department of Oral Pathology and Microbiology, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: Mb
authors.initials: M
authors.lastname: Radhika
authors.affiliation: Department of Oral Pathology and Microbiology, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: K
authors.initials: K
authors.lastname: Paremala
authors.affiliation: Department of Oral Pathology and Microbiology, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: M
authors.initials: M
authors.lastname: Sudhakara
authors.affiliation: Department of Oral Pathology and Microbiology, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: M
authors.initials: M
authors.lastname: Soumya
authors.affiliation: Department of Oral Pathology and Microbiology, Krishnadevaraya College of Dental Sciences, Bangalore, Karnataka, India.
authors.forename: Mohsin
authors.initials: M
authors.lastname: Gadivan
keywords: Cell proliferation; Ki-67 LI (Labeling Index); Oral epithelial dysplasia; Oral squamous cell carcinoma