Carcinoma of the nasal cavity and paranasal sinuses in dogs: descriptive epidemiology.

A retrospective study of medical records from 15 veterinary university teaching hospitals and clinics yielded 504 dogs with microscopically confirmed primary carcinoma of the nasal cavity or paranasal sinuses. When compared to the hospital population at risk, males showed a 1.3 fold excess risk (p less than or equal to 0.05), adjusted for age and gonadal status, compared to females. The male excess persisted from 1 through 14 years of age. Dolichocephalic dogs (specifically the Collie and Sheltie) had a higher risk than other dogs and brachycephalic dogs had a lower risk, but these variations may not be a simple function of skull type. Seven breeds of dogs were identified with a significantly high risk and two with low risk. Among breeds with mesaticephalic type skulls, risk was not associated with adult body weight, used as a measure of body size and tidal air requirement. Mongrel dogs, often spared from other types of cancer, displayed the same risk as all breeds combined, suggesting the influence of environmental factors.