Southcentral Division 2021
Signalment:9-yr-old Quarter Horse gelding
History:The horse presented with a mandibular mass that rapidly and progressively grew over the course of six weeks. On external examination, a large firm swelling was noted beneath the tongue. Radiographs revealed a large, invasive, and lytic mass that encompassed the rostral mandible to the level of both mandibular canines. A rostral mandibulectomy was performed, and the rostral mandible was submitted.
Gross Lesions:A 12x11x10 cm rostral mandible including canine teeth with an approximately 8x7x5 cm, firm to hard, round, symmetrical, tan to red mass was submitted. The mass encompassed the mandible and protruded ventrally. On cut surface, the mass was tan to yellow, firm to hard, heavily cavitated, and effaced surrounding alveolar bone.