Ki67 Labelling Index predicts clinical outcome and survival in oral squamous cell carcinoma

Abstract Objective To investigate the Ki 67 expression and its correlation with clinicopathological features and 3 years as well as 5 years survival rate in oral squamous cell carcinoma (OSCC). Methodology Total 217cases of OSCC primarily treated with surgery with or without radiation were included. All patients were followed up for 3 years and 150 were followed up of 5 years for disease free survival. The immunohistochemistry was carried out on neutral buffered formalin fixed paraffin embedded tissue to evaluate the expression of Ki67. Results The Ki67 labeling index (LI) was significantly higher with respect to adverse clinicopathological parameters such as histopathological grading (p<0.001), clinical TNM staging (p<0.001) and nodal metastasis (p<0.001). The OSCC patients survived for less than 3 and 5 years were showed significantly higher Ki67 LI as compared to diseases free survived more than 3 and 5 years(p<0.001). The three years survival rate of OSCC patient significantly higher with low Ki67 LI (≤45) 96.2%, followed by moderate Ki67 LI (46 to 60) 60.7% and high Ki67 LI (≥61) 37.7% (p<0.001). The five years survival rate of OSCC patient statistically significantly higher with low Ki67 LI (≤45)93.3%, followed by moderate Ki67 LI (46 to 60) 46.8% and Ki67 LI (≥61) 23.3% (p<0.001). Conclusion The measurement of cell proliferative activity by using Ki67 antigen expression in individual OSCC might provide unique, predictive information on clinical outcome, prognosis and deciding treatment modalities in OSCC.

Oral submucous fibrosis: An enigmatic morpho-insight

Oral submucous fibrosis (OSMF) is a chronic progressive, scarring disease affecting oral, oropharyngeal, and sometimes the esophageal mucosa. It is characterized by the progressive fibrosis of the submucosal tissue. The pathogenesis of OSMF has been directly related to the habit of chewing areca nut and its commercial preparation, which is widespread in Indian subcontinent and Southeast Asia. The areca nut has been classified as a “group one human carcinogen.” Oral squamous cell carcinoma in the background of OSMF is one of the most common malignancies in South and Southeast Asian countries. Malignant transformation has been reported in 7%–12% cases of OSMF. Histopathological spectrum of OSMF includes the apparent alterations observed in the epithelium and connective tissue. Epithelial atrophy and sometimes epithelial hyperplasia with or without dysplasia are the peculiar alterations seen in the epithelium. In the connective tissue, there is extracellular matrix remodeling which results in excessive collagenization. Further cross-linking of collagen leads to hyalinization which makes the collagen resistant to proteolysis. Owing to fibrosis in the connective tissue, there is narrowing of blood vessels which further results in compromised blood supply to the local tissue milieu, that is, hypoxia. This tissue hypoxia elicits angiogenesis which may result in the malignant transformation of OSMF. Perpetual irritation of areca nut and its constituents to the oral mucosa leads to upregulation of pro-inflammatory cytokines and further juxtaepithelial inflammation. Thus, these coordinated reactions in epithelium and connective tissue leads the OSMF toward malignant transformation