Study of Ki67 in odontogenic benign tumors

Abstract

The aim of the present study was to investigate the Ki67 expression level and to measure the cell proliferation index (Ki67) in odontogenic benign tumors.This was an analytical cross-sectional study of odontogenic benign tumors. The sampling was non-probabilistic with an exhaustive recruitment including all biopsy or surgical excision specimen of odontogenic benign tumors. Ki67 immunohistochemistry was performed on histological sections of paraffin-fixed tissues of 3µ thickness with the Ki67 (MM1) monoclonal antibody. The studied variables were sociodemographic, clinical and histopathological. The data have been analysed with SPSS 20.0 software.: Ameloblastoma represented 50.9% of cases and cemento-osseous dysplasia 36.4%. Among the 28 ameloblastoma cases, the 15 (53.6%) were plexiform type, the 7 (25%) follicular type and the 6 (21.4%) unicystic type. The percentage of Ki67 labelled cells was less than 1% in 74.6% (n=41) of the tumors and was equal to 5% in 12.7% (n=7) of cases. A Ki67 law labelling was found in 87.3% (n=48) of tumours and a negative labelling in 12.7% (n=7) of cases. The odontogenic benign tumors had a weak Ki67 expression level and a low epithelial cell proliferation index. The Ki67 could not therefore be used as a predictive biomarker of tumor cell proliferation and the risk of recurrence in odontogenic benign tumors.