title: Oral masses in two cats.
abstract: Incisional biopsies from the oral cavity of 2 adult cats were submitted for histological investigation. Cat No. 1 showed a solitary well-circumscribed neoplasm in the left mandible. Cat No. 2 demonstrated a diffusely infiltrating neoplasm in the left maxilla. Both tumors consisted of medium-size epithelial cells embedded in a fibrovascular stroma. The mitotic index was 0 to 1 mitosis per high-power field. The epithelial cells showed an irregular arrangement forming nests or streams in cat No. 1, whereas a palisading growth was noted in cat No. 2. Both tumors, especially that of cat No. 1, showed multifocal accumulations of amyloid as confirmed by Congo red staining and a distinct green birefringence under polarized light, which lacked cytokeratin immunoreactivity as well as and AL and AA amyloid immunoreactivity. In addition, the amyloid in cat No. 2 was positive for the odontogenic ameloblast-associated protein, formerly termed APin. In sum, both cats suffered from an amyloid-producing odontogenic tumor, but their tumors varied with respect to morphology and type of amyloid produced.
authors.affiliation: Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany. patricia.bock@tiho-hannover.de
authors.forename: P
authors.initials: P
authors.lastname: Bock
authors.forename: V
authors.initials: V
authors.lastname: Hach
authors.forename: W
authors.initials: W
authors.lastname: Baumgärtner
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000473:pathology* / Q000601:surgery; D002415:Cats; D003937:Diagnosis, Differential; D005260:Female; D008297:Male; D008339:Mandibular Neoplasms / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D008441:Maxillary Neoplasms / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D009808:Odontogenic Tumors / Q000473:pathology / Q000601:surgery / Q000662:veterinary*