Extensive venous thrombosis and hind-limb edema associated with adrenocortical carcinoma in a dog

A 10-year-old, spayed female, mixed-breed dog was referred for evaluation o f bilateral hindlimb edema and weakness. Abdominal ultrasonography showed i ncreased echogenicity of the lumen of the caudal vena cava from the level o f the urinary bladder to the level of the cranial pole of the right kidney. Bilateral saphenous venograms displayed numerous filling defects in the ca udal vena cava, right external iliac vein, right femoral vein, and the righ t common iliac vein. Extensive venous thrombosis was diagnosed, and the ani mal was euthanized. Necropsy confirmed the presence of venous thrombosis an d revealed a right adrenocortical carcinoma that had invaded the caudal ven a cava.