Today’s case is a 13-year-old male Golden Retriever with a history of productive cough and weight loss. What is your assessment?
Radiographs: There is a large soft tissue opacity mass in the caudal thorax, which appears to be within the accessory lung lobe. It silhouettes with the caudal cardiac silhouette and the mid portion of the diaphragm. On the left lateral projection, there are multiple areas of increased opacity in the ventral right middle lung lobe. A thin-walled bulla is visible in the left cranial lung lobe at the third intercostal space. The cardiovascular structures are normal. No abnormalities are seen in the pleural space or musculoskeletal system. The v/d projection is presented with the left side on the left of the image.
CT: The mass is confirmed to be in the accessory lung lobe, displacing the caudal vena cava ventrally and the esophagus laterally. The accessory lobar bronchus is visible within the mass. Nodules are present in the right middle lung lobe. The large bulla seen on radiographs is confirmed to be in the left cranial lung lobe. Multiple additional bullae are present throughout the lungs.
Primary lung tumor such as adenocarcinoma with probable pulmonary metastasis. The opacity in the right middle lung lobe may also be pneumonia or granulomatous change. The bulla may be congenital or degenerative change.
An ultrasound guided fine needle aspirate was performed. Cytology was consistent with primary pulmonary adenocarcinoma.