Neuroectodermal influence in odontogenic cyst and tumor: evidence through CD56 immunoexpression.

Background And Objectives: CD56, associated with neuroectodermal differentiation of the embryonal cells, is often considered a marker of neural lineage. Odontogenic keratocysts (OKCs) are of particular interest because of their characteristic histopathologic features, high recurrence rate, and aggressive behavior. CD56 immunoreactivity in these lesions has been reported with very high frequency. The present study analyzes the immunoexpression of CD56 in ameloblastoma (AM) and OKC to infer neuroectodermal influence in the pathogenesis of odontogenic lesions and its correlation with clinicopathologic parameters.

Materials And Methods: Fifty histopathologically confirmed cases of OKC and AM, 25 from tooth-bearing (TB) and molar-ramus (MR) regions each, and 5 dental follicular tissues as control were collected from the department archives and immunohistochemical analysis with CD56 was carried out.

Results: CD56 immunopositivity was seen in 64% AM and 36% OKC cases. The majority of AM cases showed cytoplasmic expression in the peripheral cells of odontogenic islands; similarly, OKC cases showed continuous and uniform cytoplasmic expression in the basal and parabasal cells of the cystic lining. CD56 immunopositivity was found in more AM cases as compared to OKC cases in both the TB and MR regions.

Interpretation And Conclusions: The assessment of CD56 immunoexpression in odontogenic cyst and tumor (AM) may aid in understanding the role of neuroectodermal influence in the etiopathogenetic pathways and a possible influence of CD56 on the clinical behavior and aggressiveness of the odontogenic lesions. A correlation of CD56 expression with the clinical outcome of the disease (site, perforation, root resorption, and tooth displacement) can help envisage possible prognostic assessment for these lesions.