Infiltrative adrenal tumor into the caudal vena cava : diagnostics and treatment options

Abstract

A 9 year old male castrated Shetland Sheep-dog was presented to the Internal Medicine Service at Cornell University Hospital for Animals (CUHA) for further evaluation of suspected hyperadrenocorticism. The patient exhibited signs consistent with hyperadrenocorticism (HAC) beginning 1 year earlier, as observed by the owners. On presentation he was quiet, alert and responsive. Mild alopecia was noted dorsally; he exhibited signs of weakness in his hind limbs, and was painful on abdominal palpation. Blood-work showed a mild mature neutrophilia with lymphopenia and eosinopenia, and elevated liver values. Abdominal ultrasound revealed a focal isoechoic mass in the left liver lobe, and increased echogenic material within the gallbladder. A large left adrenal gland was noted, 2.5 x 2 x 3 cm, extending 3 cm into the caudal vena cava, partially occluding the lumen. Several treatment options were presented, but the owner elected not to pursue treatment at the time of presentation. This case report will discuss methods used to diagnose HAC, differentiating between pituitary dependent and adrenal dependent HAC, pheochromocytomas, and medical and surgical treatment options.