Oral Squamous Cell Carcinoma in a Budyonny horse: A case report

Squamous cell carcinoma (SCC) is a cancerous growth originating from the stratified squamous epithelium and is the most frequently diagnosed oral tumor in horses. This case report describes the clinical, imaging, and histopathological characteristics of gingival SCC in a 23-year-old Budyonny gelding with a history of multiple unsuccessful treatments, including a prior tumor excision attempt. The horse presented with a large, space-occupying soft tissue mass associated with excessive drooling, and lateral tongue protrusion. Laboratory findings were consistent with cancer-related anemia, while diagnostic imaging demonstrated extensive mandibular bone lysis consistent with the tumor’s aggressive nature. Histopathology confirmed grade III gingival SCC, characterized by keratin pearl formation and a high mitotic index. Due to the poor prognosis, high treatment costs, and advanced stage of disease, the owner declined further therapeutic intervention. The horse succumbed to the disease and died 6 months after presentation. This case emphasizes the challenges of managing advanced gingival SCC in equines and underscores the importance of early detection and timely intervention.