Epidemiology of ocular pathology in domestic animals: insights from a 20-year retrospective study.
Authors: Garcia Jamile Macedo, Rogerio Guilherme da Silva, Rossatto-Júnior Carlos Alberto, Bezerra Lorena Santos, Schulz Érica Thurow, de Morais Raphael Assis Leandro, Dagli Maria Lucia Zaidan
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Ocular Pathology in Domestic Animals Over two decades, researchers at the University of São Paulo analysed 375 ocular and periocular tissue samples from domestic animals (64% dogs, 15.2% cats, 12.3% horses, and others) to establish the prevalence and distribution of eye diseases and determine whether clinical field diagnoses aligned with histopathological findings. Neoplastic lesions dominated the sample set at 80.53%, with squamous cell carcinoma accounting for over one-fifth of all cases, followed by inflammatory lesions (10.4%), and hyperplastic, cystic or infectious conditions making up the remainder—importantly, eyelids emerged as the most commonly affected anatomical site. Species-specific patterns emerged: cattle presented with third eyelid SCC, whilst cats and horses showed predominant involvement of eyelids and conjunctiva, and dogs displayed notable frequencies of meibomian adenocarcinoma and ocular melanoma; additionally, brachycephalic dog breeds demonstrated statistically fewer neoplastic lesions than their non-brachycephalic counterparts. Clinical assessment correlated with histopathological diagnosis in 84.1% of cases, though moderate agreement (by Kappa coefficient) suggests field practitioners may be missing or misidentifying subtle pathology. These findings highlight that routine histopathological submission—particularly for suspected ocular neoplasia and periocular lesions—remains essential for accurate diagnosis and appropriate treatment planning across equine and companion animal practice.
Read the full abstract on PubMed
Practical Takeaways
- •Any eyelid, third eyelid, or conjunctival mass in horses, cattle, cats, or dogs should raise suspicion for squamous cell carcinoma and warrant biopsy for definitive diagnosis
- •Clinical examination alone is insufficient for ocular neoplasia diagnosis—histopathological evaluation is essential for accurate diagnosis and treatment planning in 16% of cases where clinical suspicion was incorrect
- •Brachycephalic dog breeds have inherently lower risk of ocular neoplasia compared to other dog breeds, which may influence screening protocols and owner counseling
Key Findings
- •Neoplastic lesions represented 80.53% of 375 ocular and periocular samples, with squamous cell carcinoma being the most common at 20.26%
- •Eyelids were the most frequently affected anatomical site across species; third eyelid SCC was particularly common in cattle
- •Brachycephalic dog breeds showed significantly fewer neoplastic lesions compared to non-brachycephalic breeds
- •Clinical suspicion matched histopathological diagnosis in 84.1% of cases, highlighting the importance of tissue confirmation