Pheochromocytoma in dogs: 13 cases (1980-1985).

Thirteen cases of canine pheochromocytoma seen at the University of Minnesota Veterinary Teaching Hospital between 1981 and 1985 were reviewed. In 8 cases, the neoplasms were locally invasive; in the remaining cases, they were confined to the adrenal gland. Clinical signs compatible with fatal cardiovascular collapse secondary to a hypertensive or arrythmic episode were observed in 6 of 8 dogs with invasive neoplasms that died during examination or shortly thereafter. The remaining 2 dogs with invasive neoplasms had antemortem diagnoses of adrenal gland neoplasm with metastases and were euthanatized. Invasion or encroachment of the caudal vena cava in 6 dogs and encroachment of the aorta and other regional vasculature in 2 dogs were discovered at necropsy. In 5 dogs, the noninvasive pheochromocytoma was found incidentally during necropsy.