Re: Insulinoma

In Reply to: Insulinoma
Category:   Medical
Posted by:  Helen Turner
Posted on:  May 16, 2002 at 09:38:04

: My Jackie is 9 years old and has been diagnosed with insulinoma. I have scheduled surgery for him. I'd like to know if any other "parents" of Jacks have had to deal with this and what their experience was. Did they decide to treat medically, surgically? How did it work out for them? Did they gain much time?

Response:

Helen,
As you know none of us are Vets, but I did do a Web search and found two articles, on this and one I cut and pasted and the other I will link you too. I also read that this is uncommon in dogs and do I don't think there will be very many owners that are having this problem.
Hope this helps you some.
Regards
Linda

What is an insulinoma?

Insulinoma is a type of tumor found in the pancreas. Normally, the pancreas secretes insulin to control blood sugar in the body. Insulin is an essential factor for metabolism of carbohydrates. Insulinomas secrete an excess quantity of insulin. Excess insulin leads to low sugar (glucose) levels (hypoglycemia) in the blood. Low blood sugar may result in an emergency situation due to presence of seizures and weakness. Insulinoma is uncommon in dogs and rare in cats. Dog breeds more likely to develop insulinoma than other breeds are the standard poodle, boxer, fox terrier, Irish setter, German shepherd dog, golden retriever, and collie. In cats, the Siamese may have an increased likelihood of developing insulinoma than other breeds.

What causes insulinoma?

The cause of insulinoma is unknown. The cause of the low blood sugar that produces the signs of insulinoma is an insulin-producing tumor, usually malignant, of the pancreas.

What are the signs of insulinoma?

The signs of insulinoma are related to low blood sugar. Signs may or may not be related to eating, excitement, or exercise. Signs progress with time. The most common sign in dogs is seizures. Other signs in dogs include weakness, collapse, muscle twitching, abnormal behavior, lethargy, depression, wobbliness of the limbs, hunger, weight gain, excessive urination and excessive thirst, and fatigue. Signs in cats are seizures, wobbliness of the limbs, muscle twitching, weakness, lethargy, depression, lack of appetite, weight loss, and excessive thirst.

How is insulinoma diagnosed?

Insulinoma is diagnosed by a complete work-up to determine the cause of the low blood sugar. In most cases, the animal will have low blood sugar on routine blood tests. To further identify the cause of the low blood sugar, blood sugar levels and insulin levels are tested. This is done by withholding food and collecting blood samples every 1 to 2 hours to determine glucose and insulin levels. When the blood sugar drops (because the animal is fasting), the blood is analyzed for insulin. High insulin levels in an animal with low blood sugar indicate that an insulinoma is likely. Chest and abdominal radiographs (X-rays) may be done. They are usually normal in animals with insulinoma, but they help evaluate the animal for tumors outside the pancreas, which sometimes cause low blood sugar.

How is insulinoma treated?

The most important aspect of treatment for insulinoma is diet. The pet should be fed 4 to 6 small meals a day. The veterinarian will prescribe a diet high in protein, fat, and complex carbohydrates and low in simple sugars. Semi-moist food should be avoided. Surgical removal of the tumor is an option and helps animals with insulinoma have a longer lifespan than if they do not have surgery. If diet changes with or without surgery are ineffective in controlling blood sugar, steroids by mouth are started. If diet and steroids prove ineffective in controlling blood sugar, other drugs are available that can help control blood sugar.

What is the prognosis (outcome) for pets with insulinoma?

The prognosis for animals with insulinoma varies. The tumor has been shown to spread (metastasize) in 40% of animals with insulinoma. Dogs can survive for as little as 2 months or as long as 5 years. Cats have been shown to survive up to 18 months. Surgical removal of the tumor improves survival time.