Ki-67 Prognostic Value in Different Histological Grades of Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Abstract

Introduction: Abnormal cell proliferation appears to be a possible predictor of tumorigenesis, Ki-67 protein expression is closely related to the cell proliferation and could be used as a biomarker for the growth in the most of human tumors. The aim of the study: Investigating of Ki-67 expression in the pathological grades of oral epithelial dysplasia and oral squamous cell carcinomas. Materials and Methods: The sample consisted of 30 formalin-fixed, paraffin-embedded specimens of oral epithelial dysplasia (OED), 30 other of oral squamous cell carcinomas (OSCC), and 10 normal oral epithelium (NOE) were conventionally stained with hematoxylin and eosin and immunohistochemically stained with Ki-67 monoclonal antibody. Results: Expression of Ki-67 was restricted to the basal layers in the normal oral epithelium whereas Ki-67 positive cells in oral epithelial dysplasia (OED) were located in the basal, suprabasal and spinous layers, Ki-67 expression was increased in high-risk cases. Ki-67 positive cells in well-differentiated (OSCC) were located mainly in the periphery of the tumor nests, in moderately-differentiated (OSCC) were located in both peripheral and part of a center of the tumor nests whereas it was diffused in most of the Poorly-differentiated (OSCC). Statistical analysis indicated a significant difference between the expression in (OED) and (NOE), (OSCC) and (NOE), and no differences between (OED) and (OSCC). Conclusion: This study has concluded that Ki-67 antigen could be used as a marker for the histological grading of OED and OSCC, Expression of Ki 67 increased according to the severity of oral epithelial dysplasia.

Keywords: Ki-67 antigen; Oral epithelial dysplasia (OED); Oral squamous cell carcinomas (OSCC); NOE.

Figure 1

T he Nuclear Ki-67 Positivity was Found in the Basal of the Epithelium

Figure 2

The Nuclear Ki-67 Positivity was Found in the Basal and Parabasal Layers of the Epithelium

Figure 3

The Nuclear Ki-67 Positivity was Found in the Basal, Parabasal and Some of the Spinous Layers of the Epithelium

Figure 4

The Nuclear Ki-67 Positivity was Found in the Basal, Parabasal and Most of Spinous Layers of the Epithelium

Figure 5

The Nuclear Ki-67 Positivity was Found in the Peripheral Area of Tumor Islands

Figure 6

The Nuclear Ki-67 Positivity was Found in the Peripheral Area and Part of the Centerarea of Tumor Islands

Figure 7

The Nuclear Ki-67 Positivity was Found in the Peripheral Area and Most of Centerarea of Tumor Islands

Figure 8

Graphical Demonstration of Immunohistochemical Quantitative Results of the Ki-67 Protein in the Study Sample. NOE, normal oral epithelium; OED, oral epithelial dysplasia; PDOSCC, poorly differentiated oral squamous cell carcinomas; MDOSCC, moderately differentiated oral squamous cell carcinomas; WDOSCC, well differentiated oral squamous cell carcinomas.