Case Study

Adrenal carcinoma with invasion of the caudal vena cava in a 14 year old FS mixed breed dog

A 14-year-old FS mixed breed dog was presented for pacing, lethargy, and intermittent vomiting and diarrhea over the course of 1-2 months. The physical exam was unremarkable. The only abnormality on urinalysis was 1+ proteinuria with urine culture yielding growth of Escherichia coli. Abnormalities on blood chemistry were increased creatinine and hyperglycemia. T-4 result was low but free T-4 was within normal range. CBC and survey thoracic and abdominal radiographs were all within normal limits. The patient was treated with Baytril, but presented a few weeks later for vomiting and decreased appetite. Abnormalities on recheck urinalysis and blood chemistry included 1+ proteinuria, 2+ glucosuria, azotemia, and elevated AST activity at that time. The patient was treated with I.V. fluids, Cerenia, Famotidine, Baytril, and started on insulin.

Sonographic Differential Diagnosis

Invasive right adrenal mass. Pheochromocytoma or adenocarcinoma is most likely.

Image Interpretation

An aggressively invasive hypoechoic right adrenal mass is seen occupying most of the caudal vena cava.

DX

Adrenocortical carcinoma

Outcome

The patient was humanely euthanized due to financial constraints.

Clinical Differential Diagnosis

Gastrointestinal clinical signs – neoplasia, partial obstruction, chronic infections (Salmonella, E. coli, Campylobacter). Chronic kidney disease, primary diabetes mellitus, functional/neoplastic adrenal gland disease, incidental UTI.