As concerns clinical ailments (symptoms) functional and non-functional carcinoids are distinguished. The non-functional type, i.e. without hormone production, is usually discovered late. Symptoms include abdominal pain, weight loss, bowel obstruction, occasionally bleeding or jaundice. In contrast, functional carcinoids (of the small intestines) produce active hormones such as serotonin. This leads to "carcinoid syndrome" once the tumor has spread to the liver.

The carcinoid syndrome is characterized by:

  •     Flush attacks, sometimes accompanied by cardiac palpitations and sweating
  •     Persistent diarrhea
  •     Abdominal pain (often cramping)
  •     Bronchial wheeze

Interestingly, carcinoids of the appendix or rectum are almost never accompanied by any such symptoms; they usually exhibit the non-functional form of the disease.

Patients with hormone-active tumors of the pancreas often suffer from one of the following symptoms or syndromes:

Insulinoma: Patients with insulinomas (of the pancreas) usually suffer from low blood sugar levels (hypoglycemia). Hypoglycemia can manifest itself in the form of outbreaks of sweating, hunger attacks, weight gain, increased pulse rate, a state of confusion or even a loss of consciousness.

Glucagonoma: These tumors (of the pancreas) are extremely rare. Patients typically have high blood sugar levels and complain of skin rashes.

VIPoma: VIPoma of the pancreas releases the protein vasoactive intestinal peptide (VIP). This substance causes massive amounts of watery diarrhea (> 6l/day) (Werner Morrison syndrome).

Gastrinoma: Patients with gastrinoma typically suffer from recurring heartburn, chronic diarrhea, gastric or duodenal ulcers. Gastrinomas mainly originate in the duodenum and in the nearby lymph nodes; but 25-30% of the gastrinomas originate in the pancreas. The symptoms of gastrinoma disease (Zollinger-Ellison syndrome) are controlled medically (by the so called proton pump inhibitors) so effectively that the underlying diagnosis (of gastrinoma) is nowadays often missed.

Hormone-inactive (neuro) endocrine tumors of the pancreas generally manifest at an advanced stage with pain, weight loss or jaundice. Bronchial and thymic carcinoids may present with pain, coughing or difficulty in breathing. Nowadays thymic and bronchial carcinoids as well as islet cell tumors of the pancreas are often detected incidentally by a computed tomographic or ultrasound examination that is being carried out for other reasons.

Prof. Dr. med. Hans Scherübl


Center of Neuroendocrine Tumors
Prof. Dr. med. Hans Scherübl
Vivantes Klinikum Am Urban
Academic Teaching Hospital of Charité-University Medicine, Berlin
Dieffenbachstraße 1
10967 Berlin, Germany
Tel: + 49 30 130 225201
Fax: + 49 30 130 225205
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