Insulinoma is a tumor of the pancreas that occurs about twice as often in women as in men. Its occurrence is classified as rare, but the insulinoma is the most common tumor of the pancreas, which releases hormones directly into the blood (“endocrine”). The malignancy of insulinomas is 10%, so every ninth such tumor is malignant.

What is insulinoma?

People who notice symptoms of hypoglycaemia or other signs of a serious illness should consult their family doctor as soon as possible. If symptoms such as tachycardia, sweating or headaches occur, a doctor must also be consulted. See AbbreviationFinder for abbreviations related to Insulinoma.

The insulinoma got its name from the fact that it produces additional insulin and thus causes damage to the body with an excess of insulin. In nine out of ten cases, the insulinoma develops as a single tumor, so-called multiple micro-adenomas are only rarely present.

In about 50% of cases, the insulinoma not only produces insulin, but also other hormones of the digestive tract, such as the vasoactive intestinal peptide (VIP), which is responsible for the relaxation of the muscles in the stomach, intestines, trachea and bronchi, among other things. The symptoms of an insulinoma can also occur during the treatment of diabetes mellitus as a result of blood sugar-lowering drugs.

A similar clinical picture is also present in the so-called hypoglycaemia factitia, in which patients deliberately bring about hypoglycaemia in order to receive medical attention or to provoke a stay in the hospital. Both diagnoses must be ruled out before diagnosing an insulinoma.

Causes

In most cases, insulinomas arise from B cells of the islets of Langerhans in the pancreas, which have changed to become adenomatous. As a result of this degeneration, huge amounts of insulin are produced, which the pancreas releases directly into the bloodstream.

The ultimate cause for the development of these tumors has not yet been clarified in medicine. However, insulinomas occur more frequently in the context of MEN (multiple endocrine neoplasia).

The result of this genetic disease is that tumors in the pancreas, parathyroid gland and pituitary gland develop at a comparatively young age, which behave extremely aggressively and often reappear after they have completely healed.

Symptoms, Ailments & Signs

The insulinoma is characterized by the so-called Whipple triad. In Whipple’s triad, the blood sugar level is very low, less than 45 milligrams per deciliter. There are also symptoms of severe hypoglycaemia, which manifest themselves in the form of confusion, dizziness, nausea, palpitations, tachycardia and tingling as well as numbness.

The third sign is the rapid improvement of the symptoms with the intake of carbohydrates. The hypoglycemia occurs again and again with food cravings, tremors and sweating. In the long term, weight gain also occurs because the food cravings lead to more food intake. While the symptoms of hypoglycaemia can be relieved by carbohydrate intake in the short term, removal of the tumor must be considered in the long term.

Without treatment and removal of the tumor, consequential damage to the central nervous system can occur, because the constant undersupply of glucose kills many nerve cells, which are then no longer replaced. Very often there is only a single insulin-producing tumor in the pancreas. Sometimes there are multiple tumors.

In rare cases, the tumor or tumors are located outside the pancreas. The insulinoma itself does not cause any symptoms, only their increased production of insulin. Most are benign tumors that usually do not form metastases. In about ten percent of cases, however, malignant degeneration can occur.

Diagnosis & History

Insulinoma is suspected when symptoms of hypoglycaemia recur. In the so-called hypoglycaemia, the sugar level in the blood is only at or below 50 mg/dl. This manifests itself in the typical symptoms that are also found in diabetes patients, such as sweating, tremors, cravings, dizziness, nausea, paleness, tiredness, difficulty concentrating, blurred vision, palpitations (tachycardia) and violent, often irregular palpitations (palpitations).

Traditionally, medicine speaks of the so-called “Whipple Triad”, which combines a blood sugar level of less than 45 mg/dl with the described symptoms of hypoglycemia and improvement through the infusion of glucose solutions. The longer the disease is not treated, the higher the patient’s risk of obesity, which is caused by the anabolic effect of insulin.

This means that due to the insulin excess, the patient constantly has the feeling of having to take in food (especially carbohydrates) in order to keep his circulation stable. Diagnosis is by fasting the patient for three days until symptomatic hypoglycemia occurs. Meanwhile, the patient’s blood is examined at regular intervals and the levels of blood sugar, insulin and C-peptide are recorded.

If an insulinoma is present, a very rapid drop in blood sugar and an increase in the insulin-glucose ratio can be observed. The latter should drop in a healthy organism, because to the same extent that there is less glucose in the blood, the body should also stop producing insulin.

Complications

Various symptoms are caused by the insulinoma. As a rule, these depend strongly on the spread of the tumor, so that a general prediction of the complications is usually not possible. However, many of those affected suffer from severe hunger and heart palpitations. Unconsciousness can still occur.

It is not uncommon for patients to also suffer from anxiety or sweating and headaches. In addition, there is often a feeling of dizziness and nausea. Those affected also complain of impaired speech and vision and, in general, a high level of literacy. The insulinoma thus has a clearly negative effect on the patient’s quality of life. Those affected also appear tired and exhausted and no longer actively participate in life.

The patient’s resilience is also significantly reduced and limited by the insulinoma. It is not uncommon for cramps to occur in the muscles, which can lead to restricted movement. The treatment itself does not lead to further complications. With the help of medication or radiation, the insulinoma can be removed relatively easily. Surgery can also be performed. If no treatment takes place, the insulinoma can also lead to the death of the patient.

When should you go to the doctor?

People who notice symptoms of hypoglycaemia or other signs of a serious illness should consult their family doctor as soon as possible. If symptoms such as tachycardia, sweating or headaches occur, a doctor must also be consulted. Recurring ravenous hunger attacks, muscle cramps, tremors and other non-specific symptoms must also be checked if they cannot be traced back to a clear cause. At the latest when visual or speech disorders occur or even disturbances of consciousness occur, the complaints must be taken to a general practitioner. In case of serious complications, a visit to the hospital is indicated.

Previous tumor diseases or complaints of the pancreas or parathyroid glands can be risk factors. Anyone who counts themselves among these risk groups must go to the doctor immediately with the symptoms mentioned. Diseases of the gastrointestinal tract should be presented to a gastroenterologist or family doctor. Specialists in tumor diseases can also be consulted in the case of the complaints mentioned. After the initial diagnosis, further treatment in a specialist clinic is indicated.

Treatment & Therapy

The first step in treating an insulinoma is the administration of octreotide, an artificial replica of the peptide hormone somatostatin, which slows down the release of gastrointestinal hormones, including insulin.

About half of the insulinomas respond to this treatment and the insulin excess can be stopped in this way. If the insulinoma is malignant, surgical removal, called “resection” in the medical field, is unavoidable. In about 10 to 15% of insulinoma cases, metastases occur in the liver. If metastases have already formed or if surgery on the tumor is not possible, the insulinoma is treated with an interdisciplinary therapy together with chemotherapy and radiotherapy.

For surgical removal or efficient radiation therapy, the insulinoma is first localized as precisely as possible with the help of imaging procedures. If the tumor is already a few centimeters in size, it can be localized using MRI, CT, or an ultrasound of the pancreas. Otherwise, the insulinoma can be detected by determining the insulin level in the portal vein, which runs behind the pancreas and into the liver.

If the location of the insulinoma is known, the surgical intervention can be carried out. Depending on how completely the tumor can be removed, further treatment is chemotherapy and radiation therapy.

Outlook & Forecast

An insolinoma usually has a very good prognosis. In more than 90 percent of patients, surgical intervention is sufficient to completely remove the tumor. Complications occur in the first few weeks after the operation, but subside over time. Occasionally, larger parts of the pancreas have to be removed next to the tumor. This can trigger diabetes in some patients. In addition, a recurrence can form after a few years. Then another intervention is necessary.

The patients who have not been found to be completely healed must have regular follow-up checks. On the one hand, this can cause physical problems, since repeated ultrasound examinations can cause skin changes and tumors, for example. On the other hand, a chronic tumor disease represents a considerable psychological burden for the patient. In most cases, however, a positive prognosis can be made with an insolinoma.

If the tumor is detected early and the operation is successful without complications, the patient can leave the hospital after a few days and is considered cured after a few follow-up checks. In patients with existing chronic diseases or other complaints, the prognosis depends on the constitution and the individual symptoms.

Aftercare

After medical treatment of the insulinoma, follow-up care begins. For this phase, the doctor has some useful recommendations for the patient on how to support the therapy. Stress reduction and physical protection are particularly important. Chemotherapy is extremely hard on the body, so patients need a break afterwards.

Gentle sports or other hobbies that offer a bit of variety are also suitable as a balance. The positive influence on well-being should not be underestimated. In consultation with the responsible doctor, those affected learn which activities are okay. The organism may be too weak for certain activities.

Those who suffer greatly from the therapy want psychotherapeutic support. Here the fears but also the hopes of the patients are discussed. The processing helps to come to terms with the situation. Getting in touch with other sufferers also ensures a better quality of life.

In addition, the self-help group promotes understanding. Doctors often give useful advice for therapy and follow-up care that is as free of complications as possible. In order to determine any changes, patients should keep a kind of diary to identify any side effects. They then clarify this during regular check-ups with the doctor.

You can do that yourself

In any case, an insolinoma must be treated by a doctor. Some self-help measures and home remedies support medical therapy.

As with other tumor diseases, care should be taken with an insolinoma. Chemotherapy in particular can put a lot of strain on the body, which is why those affected need an appropriate balance. Depending on your physical condition, this can be a sport, a hobby or something else. The doctor can best answer which measures are permitted and which activities could harm the already weakened organism. Those affected who suffer greatly from the tumor disease should also consult a therapist. The best way to deal with the fears associated with a serious illness is to talk to a specialist. Other people affected or the responsible doctor can also be asked for advice.

In order to enable treatment without complications, possible side effects and interactions of the therapeutic measures should be recorded in a diary. The doctor can then adjust the treatment accordingly. After the treatment has been completed, regular check-ups with the doctor are indicated. If there are signs of a recurrence, the doctor must be informed immediately.