Carcinoid syndrome is a group of symptoms that appear in patients with carcinoid tumors - a type of cancer that develops in different parts of the digestive tract and in the lungs. Carcinoid syndrome is caused by the spread of carcinoid tumor, which produces the hormone serotonin. What are the symptoms of carcinoid syndrome? What is the treatment? What is the prognosis of patients?

Carcinoid syndromeis a group of symptoms occurring in patients who suffer from a malignant tumor - carcinoid tumor. Carcinoids are neuroendocrine neoplasms that develop from pheochromocytomas of the intestine and bronchial epithelial cells. In addition, they are hormonally active - they secrete serotonin, histamine as well as biologically active peptides and tachykinins. Interestingly, serotonin is responsible for the occurrence of typical symptoms accompanying the disease.

Carcinoid syndrome-Carcinoid syndrome symptoms

A characteristic feature of the carcinoid syndrome is the paroxysmal nature of the symptoms. They include:

  • watery diarrhea (occurs in 30-80% of patients)
  • short-term reddening of the skin of the face, neck and upper body (flush)
  • heart rate acceleration
  • feeling of pounding heart
  • excessive sweating
  • dizziness
  • shortness of breath
  • telangiectasia and edema erythema
  • palpable liver tumor
  • bronchospasm (rare symptom)
  • asthma attack (rare symptom)

Carcinoid syndrome - causes

Carcinoid tumors are rarely diagnosed - the annual incidence is 1 in 100,000 people. They most often develop in the gastrointestinal tract, in the appendix (50% of cases) and in the distal (end) 60 cm of the ileum (15% of cases).

In contrast, the parenteral form occurs most often in the respiratory system, more precisely in the bronchi (10%). About 25 percent patients with carcinoid tumors appear as multiple tumors of the ileum.

The peak incidence is between the ages of 40 and 70. Women are sick much more often. In young people, carcinoid tumors most often appear in the appendix. Interestingly, it is diagnosed accidentally in 0.3 percent. all patients after appendicitis surgery. In some casesgenetic predisposition to develop this type of cancer has been proven. They can also develop in people with autoimmune gastritis or in patients who are taking proton pump inhibitors for a long time.

Carcinoid tumors often do not cause symptoms for a long time and are detected accidentally during imaging diagnostics of other diseases.

The first symptoms of a carcinoid tumor, which affects the intestines, are abdominal pain, intestinal obstruction, and bleeding from the lower gastrointestinal tract. In disseminated neoplastic disease with liver metastases, the dominant symptom may becarcinoid syndrome , caused by serotonin secreted by the primary tumor. Before the development of liver metastases, serotonin is broken down by hepatic monoamine oxidase. That is why it is so important to determine the location of the primary lesion - if it is located within the portal vein drainage, the hormonally active substances are inactivated in the liver. Then we will not observe the characteristic symptoms of carcinoid syndrome.

If the primary lesion is located in the lungs and in the retroperitoneal space, both diseases appear much earlier, because the active substances are not released into the portal circulation, but directly into the systemic circulation (so they are not inactivated in the liver).

Important

Carcinoid syndrome - factors that increase the risk of symptoms

Symptoms may be caused by eating spicy foods, drinking alcohol, stressful situations or certain medications. Characteristic symptoms appear much earlier in the patient than pain symptoms or obstruction caused by a tumor of the gastrointestinal tract. The complete symptom complex of a carcinoid tumor occurs in less than 10%. cases.

Carcinoid syndrome - diagnosis

Diagnosis is made on the basis of the characteristic picture of the disease, laboratory tests and imaging tests that show the primary lesion or metastases. However, imaging tests, such as ultrasound, computed tomography, magnetic resonance and receptor scintigraphy, are used to detect only distant metastases, not the primary focus.

The concentration of chromogranin A and serotonin in the blood serum should also be determined. Increased concentration of these parameters may indicate a carcinoid tumor.

It is also worth examining whether the urinary excretion of 5-HIAA, i.e. 5-hydroxyindole acetic acid (a metabolite of serotonin), is increased, as it is the only parameter that confirms the diagnosis of this rare cancer. If a bronchial carcinoid tumor is suspected, bronchoscopy is recommended.

Carcinoid syndrome -treatment

Treatment of carcinoid syndrome includes resection (excision) of the primary tumor and the use of drugs that reduce the severity of symptoms. Surgical removal of the tumor and surrounding lymph nodes is possible, even in the case of disseminated neoplastic disease and distant metastases.

Conservative treatment is based on chemotherapy and radioisotope therapy (as long as the tumor shows the presence of the somatostatin receptor). The most commonly used drugs are etoposide with cisplatin or carboplatin. Somatostatin analogues that inhibit the secretion of serotonin, e.g. octreotide or lanreotide, are used to reduce the symptoms of carcinoid syndrome.

Carcinoid syndrome - complications

The main complication of carcinoid syndrome is tissue fibrosis caused by the secreted serotonin. The tricuspid valve is not closed (as a result of endocardial fibrosis), the outflow of urine is impaired as a result of retroperitoneal fibrosis, arthropathy, or obstruction of the visceral arteries and veins. In addition, the consequence of not treating the symptoms of carcinoid syndrome iscarcinoid crisis.

Carcinoid syndrome - prognosis

The prognosis of neoplastic disease depends mainly on the presence of distant metastases, as well as on the stage and malignancy of the tumor. The 5-year survival rate of patients with appendicitis is 99%, 75% for small intestine carcinoids, and 55% for other small intestine carcinoids.

Category:

Oncology