A Case of Rhabdomyosarcoma of Pharynx and Larynx Treated with Permanent Tracheostomy and Palliative Radiation Therapy

A 6-year-old castrated male Yorkshire terrier weighing 2.0 kg was referred with progressive inspiratory stridor. Radiographic evaluation of the cervical region demonstrated two soft-tissue densities involving the pharynx and larynx. Oral and laryngeal examinations were performed under general anesthesia. Because the pharyngeal mass obstructed the airway, a tracheostomy tube was inserted through a tracheotomy. Computed tomography images showed two separate masses of the pharynx and larynx. Rhabdomyosarcoma was diagnosed via histopathology of the pharynx. A permanent tracheostomy securing the airway and palliative radiation therapy were performed. Both tumors shrunk after palliative radiation therapy, and there was symptomatic improvement. Twenty-six months after surgery, the laryngeal tumor increased in size, and was again successfully treated by palliative radiation therapy. Forty months after permanent tracheostomy, there have been no signs of respiratory distress, local recurrence, or metastatic disease. Canine pharyngeal and laryngeal rhabdomyosarcoma has the potential to respond to radiation therapy.