Corneal Epithelial and Vascular Tumors in Domestic Species: Narrative Review of the Literature and Insights from New Cases (2016–2025)

Neoplasia of the cornea is overall rare, with corneal squamous-cell carcinoma (c-SCC) being most commonly reported in all species. C-SCC pathogenesis has been related to UV exposure in humans and horses, and to papillomavirus infection in humans. In dogs, brachycephalic conformation and chronic keratitis were associated with c-SCC. Corneal vascular tumors have also been exceptionally reported in humans, and rarely in animals. In dogs, they have been suggested to be UV-related. Except for equine c-SCCs, most studies on corneal neoplasms are case reports. The present study aimed to review the literature on epithelial and vascular corneal tumors in dogs, cats, and horses, adding new cases from our archives. Pubmed and Web of Science were searched (1980-2025) using the following keywords: cornea, neoplasia, carcinoma, hemangioma, hemangiosarcoma, dog, cat, and horse. Additionally, 94 new cases of corneal neoplasia were retrieved: 47 dogs (40 epithelial and seven vascular); 29 cats (14 epithelial and 15 vascular) and 18 horses. Signalment, clinical history, and histopathological characteristics were analyzed and compared with the literature. The combined results supported a strong association between brachycephalic dogs and c-SCC occurrence and highlighted the frequent coexistence in the feline species of symblepharon and corneal perforation, with corneal tumors.