Somatostatinoma

A Somatostatinoma is a malignant, the hormone somatostatin -producing tumor of the endocrine pancreas ( pancreatic ) or the duodenum (duodenum ). The Somatostatinoma belongs to the pancreatic tumors with endocrine structure ( Inselzellturmoren ), which in turn are expected to gastro- entero - pancreatic neuroendocrine tumors.

Description

As a functionally active tumor a Somatostatinoma pours uncontrollably from the hormone somatostatin. The distribution of somatostatin causes an inhibition of the production of other endogenous hormones, such as insulin, glucagon, growth hormone, gastrin, secretin, cholecystokinin ( CCK) and vasoactive intestinal peptide (VIP). These patients therefore suffer 95% of diabetes mellitus. Diabetes can have the bandwidth of a mild form of glucose intolerance to a serious ketoacidosis.

The Somatostatinoma concerns in the frequency of the pancreas and the duodenum approximately equal number of times. In most cases, already have formed metastases at first diagnosis of the tumor.

Prevalence and Incidence

A Somatostatinoma is a very rare cancer. The prevalence is much lower than 1:100,000. In the USA the incidence is 1:40 million.

In 93 % of cases described Somatostatinome occurred as single events sporadically. In 7% of cases there is an association with a multiple endocrine neoplasia type 1 ( MEN 1 ).

Men and women are equally affected. The disease usually occurs in the fourth to sixth decade of life on.

Diagnosis

Patients with a Somatostatinoma have significantly increased somatostatin levels in the blood. The normal value in healthy people is less than 100 pg / ml, while in patients with Somatostatinoma lie in the region above 1 ng / ml. Since the disease is extremely rare, the relevant information can be provided only in a few hospitals. With imaging techniques such as computed tomography (CT ), magnetic resonance imaging ( MRI) and endoscopic ultrasonography ( ultrasound examination ), a Somatostatinoma be well diagnosed. Especially for the localization of metastases, the somatostatin receptor scintigraphy has proven useful.

Therapy

The surgical removal of the tumor is the treatment of choice and offers the chance of a complete cure. To chemotherapeutic agents to 5 -FU and streptozocin have proved successful. In addition, usually done adjuvant treatment of diabetes.

Forecast

The prognosis in a Somatostatinoma is relatively cheap. The five-year survival rate in patients with metastases in 30 to 60 %. In patients without metastases it is almost 100 %.

First description

Ganda and Larsson described in 1977 independently by two first cases of Somatostatinoma. Ganda patient was 46 years old and had suffered for eight years from diabetes mellitus. After surgical removal of the tumor turned her back on normal blood sugar levels ( euglycemia ) a.

Two years later Krejs described the Somatostatinoma extensively in morphology and biochemistry.