Malignant aortic body tumor with metastasis to bone in a dog

Abstract

The aortic body is the most common site from which chemodectomas arise in the dog. These neoplasms are non-functional, are often locally invasive, rarely metastasize, and unless of sufficient size to cause functional impairment of the heart and large vessels, often go unnoticed. Previously reported metastatic sites include the lung, liver, mediastinal and tracheobronchial lymph nodes, myocardium, pericardial sac, and rarely, spleen, kidney, adrenal gland, pancreas, and brain. Only two reports cite metastasis to bone, one involving the vertebral body of L4 and the other involving the vertebral body of T8. A 5-year-old male Doberman Pinscher dog had a history of lameness and soft tissue swelling over the left hemipelvis. Radiographs showed extensive osteolysis of the wing of the left ileum and focal pulmonary densities. At necropsy, there was a 2 x 4 cm draining wound that extended deep into the gluteal musculature of the left hemipelvis. The entire wing of the left ileum was reduced to only a few fragments of bone. At the base of the heart, a firm, firm, white, 2 x 2 cm mass was in the soft tissue between the aortic and pulmonary arterial trunks. Microscopically, tissue sections from these locations had the characteristic features of an aortic body tumor.