Oral Fibrosarcoma and It’s Surgical Treatment in A Russian Toy Terrier Dog

This case report describes the surgical treatment of an oral fibrosarcoma in a Russian Toy Terrier. A 15-year-old female Russian Toy Terrier was presented to the Surgery Clinic at Afyon Kocatepe University Animal Hospital with a primary complaint of a hard mass in her jaw and difficulty chewing. The dog's medical history revealed she had two previous surgeries at a clinic in Russia that were performed by a separate surgical team prior to presentation at our facility for a mass in the oral region. The histopathological examination of the excised mass from those surgeries was diagnosed as acanthomatous ameloblastoma or canine acanthomatous epulis. It was reported that approximately one year after the resection surgeries, the dog was presented again with swelling in the lower jaw. The clinical examination revealed a hard mass in the patient's left mandibular region, invading the mandible. Radiography confirmed that the mass had invaded the mandible and showed osteolytic lesions in the bone. Additionally, the mass was infected, with pus accumulating within it. Radical surgical resection of the mass was performed through partial mandibulectomy. Histopathological examination showed a spindle cell fibrosarcoma with features of high-grade sarcoma, classified as Grade III according to canine soft tissue sarcoma grading. In conclusion, to the authors’ knowledge, this is the first reported case of oral fibrosarcoma in a Russian Toy Terrier dog, describing its surgical treatment in Türkiye.