Pulmonary vascular amyloidosis in an aged dog

History: The carcass of a 14-year-old, female Boston Terrier was submitted for necropsy. The clinical history for the last year was dominated by recurrent and progressive episodes of dyspnea, stertor, and tachypnea. The patient had a prior history of a grade 3 cutaneous mast cell tumor that was excised years ago. Clinical investigations during the dog’s life included thoracic radiographs, which revealed a mild patchy interstitial pattern and tracheal collapse. The owner declined blood analysis and other diagnostics on several occasions due to financial constraints. The final episode was characterized by a severe respiratory crisis with oxygen saturation below 90%. Given the poor prognosis and the animal’s deteriorating condition, humane euthanasia was performed.