Carcinoid (neuroendocrine tumor)
What is a carcinoid?Increased levels of gastric acidity with heartburn and repeated gastric and duodenal ulcers result in carcinoid's increased production of the hormone gastrin.
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Carcinoid is the most common form of a malignant tumor of the appendix appendix, but is usually associated with the small intestine, rectum, or stomach.
Metastases occurring in the liver are usually a manifestation of carcinoid elsewhere in the body. The second most affected are the respiratory tract. Compared to other malignant tumors, a carcinoid grows very slowly and causes no symptoms until late in the disease.
Only at a size of one centimeter, a carcinoid unfolds malignant (malignant) character. It can produce hormones (serotonin) and release them in the body, causing symptoms such as diarrhea or redness (carcinoid syndrome).
Cancer occurs when a cell develops a mutation in its DNA. This causes abnormal cell growth. A carcinoid develops in neuroendocrine cells - nerve cells or hormone-producing endocrine cells in various organs of the body.
One factor that increases the risk of carcinoid is smoking, in addition to the age or family history of multiple endocrine neoplasia type I (MEN I). Pre-existing conditions such as gastritis or Zollinger-Ellison syndrome can lead to an increased risk of gastrointestinal carcinoid.
The increased production of serotonin by a carcinoid causes a breakdown of tryptophan and leads to niacin deficiency (pellagra), which can be associated with dermatitis, dementia and diarrhea.
Symptoms, complaints & signs
A carcinoid (neuroendocrine tumor) causes no uniform symptoms. These depend on functionally active tumors on which hormone is increasingly formed. In functionally inactive tumors there are no symptoms at the beginning. Only after a long time do they make themselves felt due to their increasing size by repressive phenomena.
Depending on the location of the tumor, stomach pain, jaundice, weight loss or shortness of breath may occur. However, when the tumor is functionally active, the symptoms dependent on the particular hormones that are increasingly formed occur much earlier. Insulin is increasingly produced by a so-called insulinoma. This leads to constant hypoglycaemia with food cravings, sweating, tremors and disturbances of consciousness.
Increased levels of gastric acidity with heartburn and repeated gastric and duodenal ulcers result in carcinoid's increased production of the hormone gastrin. If the neuroendocrine tumor forms the so-called VIP hormone (vasointestinal peptide) in excess, the patient suffers from chronic diarrhea and constant urinary urgency. The increased formation of serotonin in turn leads to the so-called carcinoid syndrome, which is characterized by palpitations, sweats, seizure-like redness of the face, colicky abdominal pain, difficulty breathing and diarrhea.
Usually a carcinoid can be treated well because it grows very slowly. Left untreated, however, metastases form in various organs such as the liver and bone and more rarely in the eye socket, heart muscle or chest. Large tumors can also cause life-threatening intestinal obstruction.
Diagnosis & History
A carcinoid is asymptomatic in most cases during its lifetime, and is more likely to be discovered by chance on operations initiated for other reasons. However, any carcinoid carries a malignant potential, even if it causes no symptoms.
If complaints occur, they are usually very vague and dependent on the location of the tumor. This includes abdominal pain, intestinal obstruction, chest pain, cough or coughing blood, wheezing, shortness of breath or increased heart rate. In particular, diarrhea, rectal bleeding or pain may indicate a carcinoid in the area of the rectum.
To diagnose a carcinoid, there are several options. Due to the increased release of hormones in the blood is a blood test. If these hormones disintegrate, increased concentrations of certain ingredients form, which is why a urine test is also applicable.
To determine the exact location of a carcinoid, imaging studies including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), ultrasound, octreotide scan and X-ray are used. Carcinoid can also be located by endoscopy, bronchoscopy or colonoscopy. To confirm the diagnosis, a biopsy is usually initiated.
Carcinoid causes the typical symptoms and complications of cancer. In this case, the life expectancy of the person affected can be significantly reduced if the tumor spreads to other areas of the body or is recognized late. Those affected suffer from a strong shortness of breath and also from a cough.
Furthermore it comes to an ulcer in the stomach and thus not infrequently to abdominal pain and to a weight loss. Also, jaundice may occur, suggesting liver discomfort. The patient's quality of life is generally significantly reduced and limited by the carcinoid. Likewise, it can lead to a so-called intestinal obstruction or to an amplified heartbeat.
Even chest pain can occur due to shortness of breath and make the everyday life of the person complicate. Treatment is usually by chemo or radiation. Most tumors can be removed. However, the further course of the disease depends on the spread of the cancer, so that no general prediction is possible. In most cases, the life expectancy of the carcinoid is significantly reduced.
When should you go to the doctor?
Signs such as palpitations, respiratory complaints or cramps indicate a serious health problem. A visit to the doctor is necessary to clarify and treat the cause of the irregularities. In case of abdominal pain, diarrhea or loss of weight, consult a doctor. If persistent and incomprehensible coughing fits, dysphagia, expectoration or respiratory distress, a doctor must be consulted. A trembling of the body, a pale skin or a discoloration of the skin should be examined medically. In particular, with a yellowing of the skin is a matter of concern.
Since without treatment a organ failure and the premature death of the person threatened, a visit to a doctor is advisable at the first signs of the disease. If existing complaints persist or increase in intensity, a check-up with a doctor should take place immediately. For a seizure-like unexplained redness of the face, neck and décolletage, a physician should be informed of the observations. The so-called flush is a special symptom that indicates the presence of the carcinoid. In rare cases it leads to a loss of consciousness and thus to a powerlessness. An emergency doctor must be contacted so that an intensive care treatment can be initiated as soon as possible.
Treatment & Therapy
The treatment of a carcinoid depends on the location of the tumor, the spread, the general state of health and the stage of the disease.
The only curative therapy for a carcinoid is a surgical procedure in which a carcinoid can be completely removed. If the carcinoid has metastasized, treatments such as radiolabeled octreotide or the radiopharmaceutical 131I-MIBG (meta-iodobenzyl guanidine) are used to arrest cancer cell growth and embolization techniques.
Radiofrequency ablation produces heat treatments that kill a carcinoid. Chemotherapy is of little use in a scattering carcinoid and is usually not induced. The administration of octreotide or lanreotide (somatostatin analogues) may reduce the secretory activity of a carcinoid and has a growth-inhibiting effect as well.
Alternative therapies can help manage cancer treatment and gain control over stress and how to cope with the diagnosis of carcinoid. These include massage, meditation or relaxation techniques such as Tai Chi and Yoga.
Outlook & Forecast
A carcinoid is usually a well-differentiated neuroendocrine tumor. Since this only grows slowly, a good prognosis can be expected with an early detection. Furthermore, the disease course of a carcinoid depends significantly on the type and location of the tumor. Neuroendocrine tumors of the appendix often do not form secondary tumors. Because of this, they have more favorable prognoses than other carcinoids of the gastrointestinal tract.
Prerequisite, however, is adequate treatment, which includes removal of the appendix and drug therapy. If successful, patients may expect a cure. In general, the 5-year survival rate in this case is 75%. However, untreated or late recognized carcinoids may be malignant. The malignant manifestation is characterized among other things by the formation of metastases. Patients with poorly differentiated or malignant carcinoids also have significantly reduced life expectancy.
In order to improve the prognosis of the malignant neuroendocrine tumor, a timely removal of the primary tumor is the drug of choice. Furthermore, life expectancy can be further increased by subsequent chemotherapy. Through these and additional measures, the progression of the disease can often be delayed for several years.
A targeted prophylaxis against a carcinoid is currently not recommended. Medical professionals therefore point to a healthy lifestyle with plenty of fresh fruits and vegetables and a low level of stress. If a carcinoid is diagnosed, serotonin-rich foods should be avoided.
Therapy for cancer is usually followed by follow-up. These are intended to recognize the recurrence as early as possible, which promises doctors better treatment options. Metastases can form on adjacent organs, for example. This concern also applies to carcinoids.
Follow-up examinations usually take place in the clinic where the first therapy was taken. The doctor agrees with his patient a rhythm for aftercare. This runs closely in the first year and then widens from year to year. Quarterly inspections are to be kept at least initially. After the fifth year, an annual aftercare is usually sufficient. The likelihood of a tumor recurrence has dropped immensely at this time.
The type of follow-up is aimed at a carcinoid after the specific disease. Eligible are blood and urine tests as well as imaging techniques. The last ones include sonography, endoscopy, CT and MRI. Furthermore, the aftercare also aims at supporting the patient. Thus, social, psychological and physical complaints that result from the disease are treated in a therapy. Due to their professional orientation, rehabilitation facilities promise a relatively quick return to everyday life.
You can do that yourself
Depending on where the tumor is located and what the general state of health of the patient is, various measures can be taken for the treatment.
First, tumor patients should take care and avoid stress as much as possible. The chemo or radiotherapy may be supported by a change in diet. Which dietary measures are useful and necessary depends entirely on the stage of the disease. The patient should work out an individual nutrition plan together with the doctor. After initial treatment, moderate exercise is recommended. Sport strengthens the immune system and improves wellbeing. Accompanying this, a visit to a self-help group can be useful. Not only the patients themselves, but also the relatives often need mental support. This can also be done by a therapist.
Alternative therapy helps against the stress of cancer treatment. These include, for example, massages, meditation, relaxation techniques such as yoga and acupuncture. It can also help to get as much information about the condition as possible in order to make dealing with the diagnosis of carcinoid easier. The doctor may give the patient further options for overcoming the condition and the discomfort associated therewith.