Insulinoma

Insulinoma General Information

Insulinoma is the general medical term given to a neuroendocrine pancreatic tumor that derives from beta cells, and may be also referred to as islet cell adenoma. This type of tumor retains the cell ability to synthesize insulin, which it releases into the organism, but they may also secrete other hormones as well, such as gastrin, glucagon, somatostatin, 5-hydroxyindolic acid, human chorionic gonadotropin and adrenocorticotropic hormone. The secretion of insulin may not be constant, case in which the patient will present wide fluctuations in the blood sample test results. It is a small tumor, of around 2 cm in diameter, and it is more frequently encountered in female patients than in males (typically, female patients will present such tumors 1.5 times more often than male patients).

While in 90% of the cases, it is a benign tumor with no adverse effects on the organism, around 10% of the cases have been reported to be malignant and metastases have also been noted. 10% of the tumors are multiple, and it has been shown that the rate of multiple tumors is higher in patients affected by multiple endocrine neoplasia type 1. A lot of individuals from all over the world are already affected by this medical condition, as it is known to be quite common among patients of all ages. The Insulinoma is the most commonly encountered pancreatic endocrine tumor, with an incidence of 55% of the total cases of neuroendocrine tumors. It is the most common cause of hypoglycemia caused by endogenous hyperinsulinism. The presence of the tumor may prove to be lethal in untreated cases of hypoglycemia; however the mortality rate after surgery is of around 7%, mostly due to local complications.

Insulinoma Symptoms

Patients with Insulinoma may experience a number of symptoms related to the resulting low level of blood sugar (glucose). These symptoms typically occur after long periods of time during which the patient did not ingest any food – most commonly in the morning, or after any prolonged sleep, but are also common after physical activities, such as exercising. The patient may experience blurred vision, trembling, faintness, weakness, lethargy, diplopia, palpitations, nervousness, sweating or recurrent headache. In some cases, the patient will present a catecholaminergic reaction to hypoglycemia, characterized by such symptoms as nausea, tachycardia, confusion, unsteadiness, marked personality changes and extreme hunger, but these are not very commonly encountered. There have also been cases where the patient has experienced a sudden weight gain to the point where obesity sets in.

Severe cases of hypoglycemia caused by Insulinoma presence may result in loss of consciousness, permanent nervous system damage, seizures, coma and possibly even death. This is not a complete list of all the possible signs and / or symptoms that are associated with the presence of an Insulinoma. In other words, you may experience a set of reactions that have not been mentioned here, especially since every organism tends to respond to this condition in a specific (and sometimes unique) way. In some rare cases, where the tumors are not producing any hormones at all, the patient may not experience any of the above symptoms but the condition may be characterized by other effects on the organism. It is highly advised that you check with your specialized health care professional immediately if you experience any unexpected and abnormal symptoms.

Insulinoma Treatment

In order for the examining physician to become certain of the condition and to place the diagnosis of Insulinoma, blood tests are made to measure the glucose, C-peptide and insulin levels. Other blood tests may be performed as well, in order to rule out other conditions that may cause similar symptoms in the patient. Once the diagnosis has been set, the examining health care specialist needs to locate the Insulinoma in the pancreas. This may prove to be a difficult task, due to the small size of the tumors, but there is a variety of procedures that may be employed, including detailed CT scans, endoscopic ultrasonography, MRI, positron emission tomography scans or octreotide scans. However, in some cases the tumor cannot be easily located, and exploratory surgery may be needed to pinpoint the tumor location.

The treatment of choice in completely removing any tumors present is surgery. This also results in a very high success rate, over 90% of the operations resulting in cured patients that do not require further treatment. There are several surgical procedures employed for removing the tumors. The most commonly employed one is enucleation, which consists in attempting to remove the Insulinoma while preserving the integrity of the pancreas. The procedure is generally simple, considering that most tumors appear on the surface of the pancreas. However, in cases where the Insulinoma cannot be reached or where the tumor cannot be extracted without damaging the pancreas, the surgeon may opt to perform a pancreatic resection – a removal of the part of the pancreas where the tumor is located. In order to accomplish this, several procedures are available, such as the Whipple operation or distal pancreatectomy. However, cases when the regular enucleation cannot be performed and a resection is in order are very rare. For more information on the various procedures available, as well as for the risks and recovery times, it is advised that you consult a specialized health care professional.

While the only treatment that results in a permanent removal of the Insulinoma is surgery, the patient may opt for a medication treatment if he or she cannot or will not undergo surgical procedures. Generally, this type of treatment is aimed at preventing or maintaining hypoglycemia within tolerable limits and to reduce the tumor effects on the organism, especially if the patient is affected by a malignant tumor. Medication treatment may include therapy with drugs such as diazoxide, hydrochlorothiazide or octreotide. There are several other drugs that can be prescribed in such situations, however in order to obtain more information regarding why you have been prescribed a certain drug, as well as for more information regarding the effects and possible side effects of that particular drug it is advised that you ask your prescribing doctor, a pharmacist or a nurse.