Immunohistochemical Profile of Ameloblastic Carcinoma Arising from an Amyloid-Producing Odontogenic Tumour in a Miniature Dachshund

• Published in: Journal of comparative pathology 2019-01, Vol.166, p.54-58
• Main Authors: Izzati, U.Z., Hidaka, Y., Hirai, T., Yamaguchi, R.
• Format: Article
• Language: English
• Subjects: ameloblastic carcinoma; Ameloblastoma - veterinary; Amyloid - biosynthesis; amyloid-producing odontogenic tumour; Animals; dog; Dog Diseases - pathology; Dogs; Female; Immunohistochemistry; Mandibular Neoplasms - veterinary; Neoplasms, Multiple Primary - veterinary; Odontogenic Tumors - veterinary
• ISSN: 0021-9975; 1532-3129
• DOI: 10.1016/j.jcpa.2018.10.182

A 13-year-old female miniature dachshund was presented with a centrally-located sublingual mass in the rostral mandibular region. The focally ulcerated growth completely covered the left (305) and right (405) premolar teeth and partially covered the right canine teeth (404). A punch biopsy sample revealed neoplastic proliferation of odontogenic epithelium arranged in irregular cords with frequent comedo-like necrosis. Following the initial diagnosis of ameloblastic carcinoma, a bilateral rostral hemimandibulectomy was performed. Although the detailed examination of the resected mass was consistent with the initial diagnosis, it also contained birefringent congophilic, amelogenin-labelled amyloid deposits similar to an amyloid-producing odontogenic tumour (APOT) in 30–40% of the mass, in continuity with the ameloblastic carcinoma. All neoplastic cells had diffuse moderate expression of cytokeratin (CK) AE1/AE3 and CK5, diffuse mild expression of CK14 and multifocal moderate expression of CK19. Because the APOT-like growth in the mass was histologically benign, the tumour was diagnosed as an ameloblastic carcinoma arising from an APOT.