Comparative Evaluation of Apoptotic and Mitotic Indexes in Lichen Planus, Lichenoid Lesion and Squamous Cell Carcinoma of the Oral Cavity by using Hematoxylin and Eosin Staining

Oral lichen planus (OLP) and oral lichenoid lesion(OLL) are suggested as premalignant lesions capable of transforming into oral squamous cell carcinoma (OSCC). However, their malignant potential is a matter of controversy. Since alterations in the cell proliferation and apoptosis are indicators of malignant transformation the aim of this study was to investigate apoptotic and mitotic indexes in lichen planus, lichenoid lesion and squamous cell carcinoma of the oral cavity by using Hematoxylin and Eosin (H&E) staining.

Apoptotic index (AI) and mitotic index (MI) were determined in H&E slides of 20 cases of epithelial hyperplasia (group A), 29 cases of OLP (group B), 13 cases of OLL (group C) and 28 cases of OSCC (group D).

There was a significant difference in AI and MI among the four groups (p˂0.001). Pairwise comparison of the groups showed only insignificant difference in AI between group B and groups C(P=0.52). There was no significant difference in MI between group B and group C, between group B and group A as well as between group C and group A (p>0.05).

The results of the present study revealed that apoptotic and mitotic indexes in OLP and OLL were significantly less than that of OSCC possibly due to the different nature of OLP and OLL. Although, it seems that these results did not indicate occurrence of malignant transformation in OLP and OLL. Further and more comprehensive studies are required to reach a definitive conclusion in this regard.

Apoptotic indexe (AI) and mitotic indexe (MI) were determined in H&E slides belong to 20 cases of epithelial hyperplasia (A group), 29 cases of OLP (B group), 13 cases of OLL (C group) and 28 cases of OSCC (D group).

There was a significant difference in AI and MI among the four studied groups (p˂0.001). In bilaterally comparison of groups; AI difference between two groups of B and C(P=0.52) was insignificant merely. Additionally, MI difference between groups of B and C, between B and A as well as between C and A (p>0.05) were insignificant.

The results of the present study revealed that apoptotic and mitotic indexes in OLP and OLL were significantly less than that of OSCC possibly due to different nature of these two lesions from OSCC. Although, it seems that these results do not suggest a malignant transformation in OLP and OLL further and more comprehensive studies are required for a definitive conclusion in this regard.