Radiotherapy of malignant nasal tumors in 21 dogs.

The nasal cavity of 21 dogs with malignant nasal neoplasia was treated with radiation. Preirradiation surgical debulking of the tumor was done in 18 of the dogs. Three dogs were treated with L-phenylalanine mustard after radiotherapy. The range of survival times (5 to 79 months), mean survival time (25 months), median survival time (23 months), 1-year survival rate (57%), and 2-year survival rate (48%) were encouraging and suggested that the described treatment was satisfactory for malignant nasal tumors. Dogs tolerated the treatment well. Signs of nasal cavity disease such as periodic nasal discharge, periodic sneezing, and occasional nasal obstruction by mucus persisted in surviving dogs.