Acanthomatous ameloblastoma in a female Spitz dog with rare atypical histomorphology: A case study

A 6 year old female Spitz dog was admitted to Teaching Veterinary Hospital at Chittagong Veterinary and Animal Sciences University with the history of inappetance and asymmetric lowerjaw. Oral inspection revealed a pair of pale enlarged lobulated mass around the third molar tooth of the left mandible. The dog was clinically diagnosed with epulis and successfully cured by surgical excision. Histopathological section of the excised masses revealed characteristic features of acanthomatous ameloblastoma with some atypical lesions. Multifocal areas of ameloblastic islands were found in the dense sheet of proliferating epithelial layer protruding towards the sub epithelial connective tissue stroma. These islands were characterized with irregular epithelial stratification at the basal layer. Besides, presence of ghost cells was the unusual findings for such case. Prominent intercellular bridging and nuclear polymorphism in odontogenic cells were other decisive characters of the lesion. Based on the histomorphological appearance, the gingival tumor was designated as canine acanthomatous ameloblastoma (CAA) with atypical histomorphology.