12 year old DSH cat

Diagnosis

On CT images, the mass was peripherally contrast enhancing and contacted both the heart and the diaphragm. The caudal vena cava was in contact with the mass and mildly compressed, and the esophagus was dorsally displaced. Differentials remained a caudal mediastinal or accessory lung lobe mass, likely neoplastic. The mass was found to be adhered to the pericardium and diaphragm at surgery, and was non-resectable. Necropsy diagnosis was accessory lung lobe adenocarcinoma with extension to the diaphragm and epicardium.