Prognostic factors and survival after radiotherapy for intranasal neoplasms in dogs: 70 cases (1974-1985).

Survival time and 31 prognostic factors were analyzed for 70 dogs undergoing radiotherapy for intranasal tumors at the Veterinary Hospital of the University of Pennsylvania between 1974 and 1985. At the time of analysis (January 1987), 14.3% (10 of 70) of the dogs were alive. Of the remaining dogs, 34 died because of tumor recurrence, 14 died because of intercurrent disease, and 12 were lost to follow-up evaluation. Pretreatment prognostic factors that were significantly correlated with disease-free interval or long-term survival could not be identified. Notably, presence of a facial mass was not prognostically significant, suggesting that extensive disease should not preclude treatment. Median survival time of dogs with all tumor types was 16.5 months, with a 1-, 2-, and 3-year survival of 54%, 43%, and 35%, respectively. Median survival time of dogs with carcinoma was 13.5 months, with 1-year survival of 51%, 2-year survival of 37%, and 3-year survival of 31%. Orthovoltage radiation was efficacious in the treatment of canine intranasal tumors.