Surgical management of an adrenal gland tumor that had extended into the thoracic portion of the caudal vena cava in a dog

Abstract

Case description: A 14-year-old neutered female Border Collie with a 3-week history of collapse during exercise was evaluated because of recumbency, tachycardia, and hypotension.

Clinical findings: Results of biochemical testing indicated the presence of a pheochromocytoma, and CT revealed an enlarged right adrenal gland mass that extended down the right phrenicoabdominal vein into the posthepatic thoracic portion of the caudal vena cava.

Treatment and outcome: A midline celiotomy and median sternotomy were performed to allow en bloc removal of the right adrenal gland tumor and its tumor thrombus extension within the caudal vena cava. Temporary occlusion of the thoracic and abdominal portions of the caudal vena cava and both renal veins and the dual inflow to the liver (Pringle maneuver) were required. The venotomy and tumor and thrombus extractions required a 25-minute period of vascular occlusion. The dog had no major postsurgical complications. Histologic findings indicated that direct adrenal tumor invasion into the caudal vena cava wall had occurred along the established route of tumor extension down the phrenicoabdominal vein.

Clinical relevance: For the dog of this report, an adrenal tumor thrombus that extended into the thoracic portion of the caudal vena cava was surgically managed with a combined median sternotomy and midline celiotomy approach and temporary occlusion of the hepatic artery, portal vein, and abdominal and thoracic portions of the caudal vena cava. This facilitated successful manual manipulation of the tumor and enabled venotomy of sufficient size for tumor thrombus extraction.