Keratinocyte dissociation (desmolysis/acantholysis) in ameloblastoma.

Ameloblastoma is the only odontogenic tumor that displays diversified histomorphological features with subtypes like follicular, plexiform, acanthomatous, granular cell, clear cell, desmoplastic etc. In this paper we presented an extremely unusual presentation of ameloblastoma, which is characterized by desmolysis or acantholysis of stellate reticulum-like cells caused due to keratinocyte dissociation. A 35-year-old male patient presented with a painless hard 3×3 cm swelling in the mandibular right posterior region in the past 4-5 months. Radiographic examination revealed a multilocular radiolucent lesion in the body of mandible with resorption of the roots. Histopathological examination revealed ameloblastic follicles with central cells showing keratinocyte dissociation leading to desmolysis/acantholysis. Desmolytic cells were seen as an isolated entity in the follicular space with round to polygonal shaped morphology. Future retrospective studies on archival samples of ameloblastoma are recommended to relook into identification of such rare phenomenon. This will help in better understanding of the incidence rate and biological behavior of this rare variant of ameloblastoma.