Insulinoma: Causes, Symptoms, Treatment, Diagnosis
What is Insulinoma?
Insulinoma is the name that refers to a small tumor that develops in the pancreas which is responsible for producing high amounts of insulin. In majority of the cases, Insulinoma is a benign tumor but in some cases it can become malignant. Insulinoma tumors are extremely small and measure not more than 2 cm in diameter. The blood sugar levels in the body are controlled by the pancreas. The pancreas produces insulin which decreases the sugar levels in the body and stops producing it when the sugar levels become lower than normal. This is how normal blood sugar levels are maintained in the body.
What happens in case of Insulinoma is that even if the pancreas stops producing insulin, the tumor which develops in pancreas continues to produce insulin thus the blood sugar levels keeps on decreasing which may result in some potentially serious complications like hypoglycemia which can cause dizziness, blurred vision, and in some cases unconsciousness. If not treated promptly, it may even become life threatening. Treatment for Insulinoma is normally surgical where the tumor is removed in its entirety. Once the tumor is removed the affected individual completely recovers from Insulinoma.
What Causes Insulinoma?
The exact cause of Insulinoma is still not yet known and most of these tumors develop without any warning signs. Once an Insulinoma develops then the normal functioning of the pancreas is affected. Normally, the pancreas regulates sugar levels in the body through insulin. The greater the amount of insulin the lesser will be the blood sugar level.
Once all of the sugar from the food is absorbed by the body for their functions the pancreas stops producing insulin and thus controls the levels of sugar in the body but with Insulinoma the tumor continues to produce insulin which may lead to severe complications like hypoglycemia which may be very detrimental to the overall health of an individual.
What are the Symptoms of Insulinoma?
Insulinoma does not have any warning signs or any symptoms as such but when symptoms do occur they may range from mild to severe.
Some of the mild symptoms of Insulinoma are:
- Double or blurred vision
- Mood swings
- Persistent weakness
- Excessive sweating
- Abnormal hunger
- Weight gain without a known cause.
Severe symptoms of Insulinoma tend to affect the brain and the adrenal glands. The symptoms experienced may be similar to another neurological condition called epilepsy in which an individual will experience seizures.
Some of the severe symptoms of Insulinoma are:
In cases where the Insulinoma gets bigger and spreads to other parts of the body then symptoms may include:
How is Insulinoma Diagnosed?
In order to diagnose Insulinoma the treating physician will first take a look at the blood sugar levels and also the insulin levels. In cases of Insulinoma, the blood sugar levels will be very low and the insulin levels will be abnormally high. Once the physician suspects the presence of Insulinoma based on the results of the test mentioned above, then in order to confirm the diagnosis he or she may order further tests like checking for proteins that block the production of insulin, any history of medications that the patient may be taking which causes more insulin to be produced by the pancreas, and look for hormones that affect insulin production.
Additionally, the physician may admit the patient. Patient maybe put on a 72 hour fast in which the patient will not be allowed to eat or drink anything except water and he or she will be closely monitoring the blood sugar levels. Within 48 hours of the start of the fast the patient will have extremely low blood sugar levels thus confirming the diagnosis of Insulinoma.
Radiological studies may also be done in the form of MRI or CT scans to pinpoint the location of the Insulinoma. In cases where an Insulinoma is not clearly visible on a CT or MRI scan, an ultrasound may be performed to confirm the diagnosis of Insulinoma.
How is Insulinoma Treated?
Surgical removal of the tumor is the most preferred treatment for Insulinoma. In cases if there are multiple tumors, then a section of the pancreas may also have to be removed along with the tumor. This surgical removal of the tumor ensures complete recovery from Insulinoma. There are different types of surgeries performed for removal of the tumor causing Insulinoma and the type of surgery depends on the size and location of the tumor.
The most preferred surgical technique used for removal of tumor in Insulinoma is the laparoscopic technique, more so when there is a solitary tumor. In this technique a small laparoscope is inserted through a small incision in the abdomen. This laparoscope has a minature camera which gives live images of the internal structures around the pancreas and once the tumor is found it is removed thus curing Insulinoma.
In cases of multiple tumors, a section of the pancreas and in some cases a part of the stomach may also be removed as a treatment for Insulinoma. For cases where the Insulinoma becomes malignant the patient may need more aggressive treatments in the form of radiofrequency ablation, cryotherapy along with chemotherapy to treat malignant Insulinoma.
In cases where surgery is not effective then the physician may prescribe medications to keep blood sugar levels and insulin levels under control while the patient is being treated for Insulinoma.