Immunohistochemical Characteristics of Spindle Cell Ameloblastic Carcinoma in a Horse

Akihiro Ochi; Takayuki Nishioka; Shinjiro Kurimoto; Daiki Kishi; Takanori Ueno; Toshio Nukada

doi:10.1016/j.jcpa.2022.05.006

Immunohistochemical Characteristics of Spindle Cell Ameloblastic Carcinoma in a Horse

J Comp Pathol. 2022 Aug:196:1-5. doi: 10.1016/j.jcpa.2022.05.006. Epub 2022 Jun 28.

Authors

Akihiro Ochi¹, Takayuki Nishioka², Shinjiro Kurimoto², Daiki Kishi³, Takanori Ueno³, Toshio Nukada³

Affiliations

¹ Equine Research Institute, Japan Racing Association, Shimotsuke City, Tochigi. Electronic address: aki_ochi@equinst.go.jp.
² Racehorse Clinic, Ritto Training Center, Japan Racing Association, Ritto City, Shiga, Japan.
³ Equine Research Institute, Japan Racing Association, Shimotsuke City, Tochigi.

PMID: 36008038
DOI: 10.1016/j.jcpa.2022.05.006

Abstract

A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8 cm in diameter, covered the upper left intermediate and corner incisor teeth (nos. 602 and 603 according to the modified Triadan system) and radiographic examination revealed displacement and lysis of the incisors. Histologically, the tumour was composed of a dense proliferation of spindle-shaped cells and neoplastic odontogenic epithelial cells arranged in island, follicular, plexiform or sheetlike patterns. The spindle-shaped cells were immunopositive for cytokeratins AE1/AE3, 5/6, 14 and 19. The Ki-67 index was 32.6% in the spindle cell component. Based on the histological and immunohistochemical findings, the tumour was diagnosed as spindle cell ameloblastic carcinoma.

Keywords: Ameloblastic carcinoma; horse; proliferation markers.

Publication types

Case Reports

MeSH terms

Ameloblastoma* / diagnosis
Ameloblastoma* / veterinary
Animals
Carcinoma* / pathology
Carcinoma* / veterinary
Horse Diseases*
Horses
Male