Endoscopic treatment of an intrathoracic tracheal osteochondroma in a dog.

Case Description-A 1.5-year-old spayed female Bernese Mountain Dog was examined for a 6-month history of intermittent vomiting, regurgitation, wheezing, and coughing. Initially, a diagnosis of gastroesophageal reflux disease with secondary aspiration pneumonitis was made but clinical signs did not resolve with treatment. Clinical Findings-Thoracic and cervical radiography and CT revealed a sessile, irregularly marginated soft tissue opacity at the level of the fourth rib. Results of a CBC, serum biochemical analysis, and urinalysis were within reference limits. Results of abdominal ultrasonography were normal. Treatment and Outcome-Tracheoscopy revealed a firm, irregularly marginated mass apparently originating from the ventral aspect of the trachea, occluding approximately one-half of the tracheal lumen, and located 2 cm cranial to the carina. Cytologic and histopathologic examination of fine-needle aspirate and biopsy samples suggested a benign etiology; therefore, endoscopic minimally invasive laser and electrocautery resection of the mass was scheduled. A total IV anesthetic protocol was administered with an oxygen-air mixture used to decrease the risk of fire during tracheal surgery. The mass was successfully resected, and histopathologic examination confirmed a diagnosis of osteochondroma. Clinical signs resolved, and at follow-up 32 months later, no regrowth of the mass was evident.