Case Study

Right adrenal mass (pheochromocytoma) in a 6 year old MN Dachshund

The patient is a 6 year old neutered male Dachshund dog. Clinical findings include abdominal distension. (A sample of ascites was sent out for cytology and revealed serosanguinous modified transudate). Physical examination also revealed a grade 3/6 heart murmur. Medications included furosemide and enalapril. Blood work showed albumin was low at 2.3.

Sonographic Differential Diagnosis

Invasive right adrenal mass to the level of the diaphragmatic inlet obstructing hepatic circulation as well as caval circulation. Pheochromocytoma or adenocarcinoma likely. Poor prognosis. Surgery is likely not an option here. Palliative abdominocentesis and treatment for any hypertension could be considered. Antithrombotic therapy could also be considered in case any of the apparent mass is actually thrombus. However the invasive portions of the mass appear to be well organized, therefore clot formation is likely minimal.

Image Interpretation

A mineralizing right adrenal mass was noted invading the vena cava and attaching to the right kidney. This mass deviated the right kidney caudally. The mass invaded into the vena cava to the level of the hepatic vein inflow causing obstructive disease both in the vena cava and the hepatic circulation (hence the secondary ascites). Focal mineralization would suggest adenocarcinoma although pheochromocytoma is also possible. The mass invaded the vena cava to the level of the diaphragm and into the thorax. Hyperechoic fat noted throughout the cranial abdomen was due to ascites formation and artifact.

DX

Malignant pheochromocytoma

Outcome

Surgical intervention was attempted. The patient was euthanized.

Clinical Differential Diagnosis

Neoplasia, right heart failure, peritonitis, pancreatitis

Sampling

Histopathology postmortem of the right adrenal gland revealed malignant pheochromocytoma.