Differential by location for canine oral tumours....

Understanding canine oral neoplasia: intrinsic rather than extrinsic features represent key risk factors in a 39-year analysis

Yash Tipirneni, Maria Soltero-Rivera, Andrew Blandino, et al.

Background
This study evaluates canine oral neoplasms using a 39-year dataset from the University of California-Davis Veterinary Teaching Hospital. It investigates prevalence, intrinsic and extrinsic risk factors, and tumor characteristics. Oral neoplasms, though only 6% of canine cancers, significantly impact quality of life. The study highlights the need for early detection to improve outcomes, as late-stage diagnosis often necessitates aggressive treatments.

Methods
The retrospective study analyzed patient data from 1985–2024, incorporating tumor types, demographics, and environmental factors like air quality. Tumor pathology was classified using keywords. Periodontal disease assessment was performed via CT scans. Logistic regression was used to evaluate risk factors, including breed, age, sex, weight, and geographical location.

Results
Prevalence: Oral neoplasms occurred in 4.59 per 1,000 dogs, with increasing incidence over time. The most common types were oral malignant melanoma (OMM, 29%), oral squamous cell carcinoma (OSCC, 19%), and canine acanthomatous ameloblastoma (CAA, 11%).

Risk Factors:
-Age: Risk increased by 13% annually up to 13.6 years.
-Breed: Labrador Retrievers, Golden Retrievers, and Australian Shepherds had the highest risk.
-Neutering/Spaying: Sterilization increased cancer risk by up to 259%, potentially linked to age or hormonal changes.
-Environmental Factors: Air quality and geographic location were not significant predictors.
-Periodontal Disease: No clear link to oral tumors, though trends varied by size and periodontal stage.

Tumor Localization: Distinct predilections were noted:
-OMM was most common on lips and commissures.
-OSCC favored the rostral mandible.
-CAA predominantly occurred on the rostral mandible.

Limitations
As a single-institution retrospective study, findings may not represent broader canine populations. Diagnostic advances and changing tumor nomenclature over the years complicate historical comparisons. Socioeconomic factors limiting referrals and incomplete environmental data (e.g., smoking exposure) were also acknowledged as constraints.

Conclusions
Breed and age are primary risk factors for oral neoplasia in dogs, while environmental factors appear less relevant. Labrador Retrievers, Golden Retrievers, and Australian Shepherds should undergo regular screenings starting around age 9. Early detection is critical to prevent invasive treatments and improve survival. Further research into hormonal influences and other intrinsic factors is warranted.