Case Study

Left adrenal mass with caval invasion, likely pheochromocytoma, in a 11 year old MN Labrador Retriever

An 11-year-old NM Labrador was presented for evaluation of acute onset vomiting and anorexic. Physical examination showed right-sided head tilt (previous TECA), dehydration, and non-painful abdominal palpation. CBC was within reference range. Abnormalities on serum biochemistry were elevated ALP activity and amylase.

Image Interpretation

Left adrenal gland comprised an approximately 6 cm mass deviating the left kidney with pericapsular fluid accumulation around the left kidney. Invasion of the left adrenal through the left phrenic vein into the vena cava was noted. The caval invasion extended approximately to the level of the hepatic inlet. The image sets around the right adrenal demonstrated normal right adrenal with alternative views of the left adrenal mass from the right side demonstrating phrenic vein invasion.

DX

Large left adrenal mass with caval invasion.

Outcome

Normal right adrenal gland.
No overt evidence of metastatic disease, however caval invasion is extensive; therefore, surgical approach would be significantly tedious. Pheochromocytoma is suspected. CT evaluation would be ideal in this case for further assessment. Serial blood pressures are recommended. Plavix therapy could be considered to attempt to detach or dissolve portions of the invasive mass that may have attached thrombosis; however, if surgery is to be considered, then this would not be the best approach. However some reduction of the caval invasion portion of the mass may be attached thrombus and may dissolve over time. Low-dose aspirin therapy could also be considered. From personal empirical use I have found that this is sometimes beneficial in these invasive adrenal mass cases. Urine culture and sensitivity and treatment for chronic UTI, pyelonephritis is recommended as well.

Clinical Differential Diagnosis

Non-specific gastritis (dietary indiscretion, toxins, helminths, viral), foreign body, ulcer, neoplasia
Liver – neoplasia
Pancreas – pancreatitis, neoplasia