Oesophageal adenocarcinoma presenting as a foreign body induced intrathoracic abscess in a dog

A 9‐year‐old, male, entire Irish setter was referred for further investigation of a chronic cough, anorexia, weight loss and lethargy. Computed tomography revealed a large ovoid encapsulated lesion, with a gas and fluid attenuating centre, and an intralesional mineral opacity. The lesion ran close to the caudal oesophagus, and extended cranially within the pulmonary parenchyma. Endoscopy revealed a communication between the lumen of the distal oesophagus and the lesion, which contained a purulent discharge and plant material. Based on the computed tomography and endoscopic findings, the diagnosis was expected to be a thoracic abscess, secondary to foreign body migration or penetration; however, surgical resection and histopathological analysis of the lesion revealed an oesophageal adenocarcinoma. This case details the unusual presentation of an oesophageal adenocarcinoma, with endoscopic and computed tomography findings that mimicked a thoracic abscess with an intralesional foreign body.