Apoptotic and mitotic indices in oral epithelial dysplasia and squamous cell carcinoma: A comparative study.

Abstract

Assessment of apoptotic cells and mitotic figures using light microscopy is an easy and viable alternative to assess tumour behaviour. To evaluate apoptotic index (AI), mitotic index (MI) and apoptotic to mitotic index ratio (AI: MI) in different grades of oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC) in haematoxylin and eosin-stained (H&E) sections. The study included 45 cases each of OED and OSCC cases which were further subgrouped into groups of 15 each based on their grades. AI, MI and AI/MI were assessed and compared with 15 cases of normal mucosa. Apoptotic cells and mitotic figures were counted using a binocular light microscope equipped with an oculometer grid (20 × 20 squares) on the eyepiece. Cells were counted in 15 grid fields under oil immersion lenses (×100) in a stepladder fashion. AI/MI ratio was calculated. The results obtained were statistically analysed using Analysis of variance and Tukey Honestly Significant Difference tests with SPSS 20 software at a 0.05 significance level. AI increased with increasing grades of dysplasia and decreased with increasing grades of OSCC. MI increased with increasing grades of OED and OSCC. AI/MI increased with increasing grades of OED but decreased with increasing grades of OSCC. In the light of the current observations, AI, MI and AI: MI can be considered as valuable parameters to assess the biological behaviour of OED and OSCC.