Pheochromocytomas in dogs are usually benign but with potential for local invasion. Affected dogs are usually older, with an average age of 11 years.
Clinical signs associated with pheochromocytoma are often vague and may mimic more common disorders such as diabetes mellitus, hepatic or renal disease, or other neoplasms. Clinical signs frequently observed include weakness, collapse, lethargy, anorexia, diarrhea, abdominal distention, hind limb edema, vomiting, panting, weight loss, anxiety, restlessness, polyuria, polydipsia, epistaxis, seizures or acute blindness. Nonfunctional tumors can also produce clinical signs by their space occupying nature.
Systemic hypertension occurs in 43-70% of canine patients with pheochromocytoma, and concurrent hyperadreno-cortism has been found in 12% of reported cases.
The treatment for canine pheochromocytoma is surgical removal. Medical therapy can also be used for nonresectable or metastatic disease, or to stabilize the patient prior to the surgery. Generally, medical therapy is aimed at correcting systemic hypertension and cardiac arrhythmias. The prognosis is guarded. However, for dogs following surgical removal of the tumor, 50% of them survived for up to one year. Pheochromocytoma should be considered in cases which with clinical signs and concurrent hypertension.
Keyword: canine pheochromocytoma; pheochromocytoma canine; pheochromocytoma dog; pheochromocytoma dogs