insulinoma in pets
We’ve talked about the important role that the pancreas plays in the body before, but it’s been a while, so here’s a little refresher before we get to the subject at hand. The pancreas is a delicate, pinkish organ that lives right next to the stomach. It is responsible for the production of insulin, which regulates blood sugar, as well as the production of the enzymes we use to digest our food. I’ve covered both of these roles in blogs that touched on diabetes and exocrine pancreatic insufficiency (EPI).
Today we’re going to address another malady of the pancreas: the insulinoma. The cells that produce insulin are called beta cells, and just like any other cell in the body, they can become cancerous. Cancer of the beta cells is called an insulinoma, as it leads to the production of large amounts of insulin.
Insulin controls the blood sugar and is normally closely regulated by the body. Insulinomas, however, are not under this regulation, and the overproduction of insulin can lead to life-threatening hypoglycemia (low blood sugar).
Signs and symptoms
Signs of an insulinoma are mostly due to hypoglycemia, which will cause weakness, trembling, mental dullness, staggering (as if in a drunken state), and seizures. Usually these clinical signs lessen after ingestion of a meal.
Diagnosis is a multi-step process. Routine blood work will show low glucose levels during a hypoglycemic event, but causes other than insulinomas will need to be ruled out first. Hypoglycemia can occur in toy breeds, in cases of diabetics who have gotten an insulin overdose, in cases of starvation, and in pregnant females who are having trouble in labor. Hypoadrenocorticism (or Addison’s disease) can also cause hypoglycemia, so additional blood tests may be warranted to rule out this condition.
The insulin level present in the blood will aid in the diagnosis of an insulinoma, but it must be measured during a hypoglycemic event. A high insulin level at the time of a low blood sugar event is highly suggestive of an insulinoma. An ultrasound of the pancreas will allow your veterinarian to visualize the tumor.
Unfortunately, most insulinomas are malignant, but surgery is still helpful if the tumor has not spread, a cost that your Petplan pet insurance policy can help mitigate. Any surgery involving the pancreas is risky due to its delicate nature, but in these cases it is worth it – 50% of dogs have normal blood sugars for a year after surgery.
If surgical treatment is not feasible, there are multiple medical options:
- Feeding frequent small meals will combat low blood sugar episodes.
- Oral medications can suppress insulin secretion.
- Sugar supplements (Karo syrup or Nutrical) given during hypoglycemic episodes will help clinical signs.
Once diagnosed, it is important to monitor your pet for the signs of hypoglycemia and respond appropriately, either by feeding a small meal, or by giving a sugar supplement. Be sure to inform your pet’s other caregivers (pet sitter or grooming facility) of this condition as well.