Pancreatic neuroendocrine tumors

Neuroendocrine tumors of the pancreas include the insulinoma, gastrinoma, glucagonoma, somatostatinoma, VIPoma. Collectively, tumors arising from the cells of the islets of Langerhans are referred to as 'nesidiomas.

Insulinoma
An insulinoma is in most cases a benign tumor (adenoma) originating from the β-cells' of the islets of Langerhans producing insulin. The most common location is the head and body of the pancreas. The malignant variant (non-sidioblastoma) occurs only in about 5-10% of cases. Women are more often affected, it occurs between the ages of 20 and 75. a year. It is the most common of all pancreatic neuroendocrine tumors.

Clinical picture
The classic manifestation is morning hypoglycemia as a result of excess insulin production, which mainly manifests itself in the fasting state. The most manifested neuroglycopenic symptoms are headaches, diplopia and impaired vision, behavioral changes, decreased concentration, speech and consciousness disorders. Manifestations of activation of the sympathoadrenal axis (sweating, palpitations, tachycardia) occur less often.

Diagnostics
The most important criterion is the patient's clinical condition (see above). In insulinomas, a typical "Wipple's triad" is described:
 * 1) laboratory-confirmed hypoglycemia (≤ 2.5 mmol),
 * 2) the presence of symptoms of hypoglycemia,
 * 3)  adjustment of state after administration of sweet food (glucose).

Glucagonoma
Tumor arising from the A-cells of the pancreas. It is relatively rare, but often malignant and metastatic. Clinical picture:
 * necrolytic erythema migrans,
 * increased catabolism,
 * increased sugar level,
 * dyslipidemia,
 * cholelithiasis, steatorrhea.

Somatostatin
Very rare, 'malignant with early metastases to the liver. Clinical picture:
 * dyspepsia,
 * diarrhea,
 * weight loss,
 * abdominal pain, cholelithiasis, steatorrhea,
 * anemia.

VIPoma
A rare tumor producing vasoactive intestinal peptide. Clinical picture:
 * watery diarrhea, hypokalemia, acidosis.