Neuroendocrine tumors of the gastrointestinal tract

Neuroendocrine tumors of the gastrointestinal tract

Gastrointestinal carcinoid tumors form of a certain type neuroendocrine cells. These cells are scattered throughout the chest and abdomen, but most are found in the gastrointestinal tract. Neuroendocrine cells produce hormones, which help control digestive juices and muscles that help move food through the stomach and intestines. Carcinoid The tumor is most commonly found in the gastrointestinal tract and bronchi and can also produce hormones to release into the body.

Carcinoid tumors Gastrointestinal tract tumors are rare and most grow very slowly. They occur in 0.03-0.081% of patients. The tumor usually occurs in the thin ones intestines, rectum and appendix. Sometimes more than one tumor forms.

They differ. mature hormone-producing carcinoid cells and immature or non-forming and not containing serotonin. Metastases are often larger than the tumor itself.

Bronchial tumors are usually solitary and develop in the main bronchi.

Clinical picture

Often carcinoid tumors do not have pronounced clinical signs and are discovered incidentally during surgery for ileus or during autopsy after the patient's death. Sometimes  diagnosisIt is placed during appendectomy with a preliminary diagnosis of appendicitis.

 

The most characteristic symptoms when the gastrointestinal tract is affected are:

In the duodenum:

Signs and symptoms of gastrointestinal carcinoid tumors in duodenum (the first part of the small intestine) may include the following:

• Abdominal pain;
• Constipation;
• Diarrhea;
• Change in stool color;
• Nausea;
• Vomiting;
• Jaundice (yellowing of the skin and sclera);
• Heartburn.

Jejunum and ileum

Signs and symptoms of carcinoid tumors in jejunum (middle part of the small intestine) and ileum (the last part of the small intestine that connects to the large intestine) may include the following:

• Abdominal pain;
• Weight loss for no known reason;
• Easy fatigue;
• Feeling of swelling;
• Diarrhea;
• Nausea;
• Vomiting.

On the large intestine

Signs and symptoms of carcinoid tumors in the fat one bowel may include the following:

• Abdominal pain;
• Weight loss for no known reason.

 

On the rectum

Signs and symptoms of carcinoid tumors in the rectum may include blood in the stool, rectal pain, and constipation.

 

On the part of the skin – flush syndrome, prolonged cyanosis, telangiectasias, pelogroid dermatosis;
On the part of lungs – asthma;
On heart – right-sided endocardial fibrosis, tricuspid insufficiency and pulmonary stenosis.
Flush syndrome occurs with increased secretion of serotonin. There is a warming of the head, redness of the face, headache. Dizziness and hypotension are possible. In some cases, hyperplasia and inflammation of the gums are observed. Carcinoid syndrome can be caused under the influence of mental agitation, consumption of alcohol, cheese, eggs and injection of adrenaline and pentagastrin.

 

Carcinoid tumors are often associated with the syndrome of Zollinger–Ellison and peptic ulcer disease – elevated serotonin and histamine cause ischemia of the stomach mucous membrane, hypersecretion and hyperchlorhydria.

 

Diagnosis

The diagnosis is made by measuring 5-hydroxyindoleacetic acid (5-HIOC) in 24-hour urine.

Characteristic are increases in glycine, iron, copper and zinc in the urine. False positive high values of 5-HIOC in the urine can be obtained by consuming foods rich in tryptophan - bananas, walnuts, prunes, blueberries, figs, potatoes, currants. A slight increase in urinary 5-HIOC is observed in small intestinal bacterial overgrowth, disease of Whipple and gluten enteropathy.

The small size of the primary tumors makes them difficult to detect on X-ray examination of the gastrointestinal tract. Selective angiography, upper and lower fiberendoscopy with targeted biopsy are used.

If liver metastasis is suspected – ultrasound, CAT scan, laparoscopy with biopsy.

Treatments

The diet should be rich in nicotinic acid. All factors that can cause clinical manifestations of carcinoid syndrome should be avoided - alcohol, physical exertion and foods rich in tryptophan.

Pathogenetic treatment includes medications that inhibit the formation, release, and action of serotonin, inhibitors on quinine production and histamine, somatostatin as an inhibitor of the secretion of hormones that suppress intestinal secretion and motility, corticosteroids.