Neuroendocrine tumors (NETs) are rare and atypical neoplasms that can occur in various organs and tissues, but as much as 70 percent of them are located in the gastrointestinal tract. Neuroendocrine tumors produce non-specific symptoms that can indicate many other diseases, including asthma, neurosis, stomach ulcers, and even menopause. What are the types of endocrine tumors and what are the symptoms?
Neuroendocrine tumors,otherwiseneuroendocrine tumors,abbreviatedNET , these are tumors quite rare and very specific at the same time. Due to the fact that their symptoms can mimic those of a wide variety of diseases, they are difficult to recognize and can take years to develop.
Often, patients, before a correct diagnosis is made, are treated for other conditions, such as: gastrointestinal ulcers, irritable bowel, asthma, lung cancer, and even alcoholism or mental illness. Mature women often even ignore the symptoms of neuroendocrine neoplasms, suspecting the onset of menopause.
This is mainly due to the fact that NET tumors are very rare, and doctors who do not have contact with them on a daily basis in their offices do not suspect this neoplasm.
Despite the increase in the detection of neuroendocrine tumors over the last 20 years, the correct diagnosis is still too rare - the statistics show 3-5 cases per 100,000 inhabitants. Meanwhile, they occur more frequently. This is evidenced by autopsies, during which neuroendocrine tumors are detected in 84 patients per 100,000 inhabitants.
The disease affects adults, most often in the sixth decade of life. Neuroendocrine tumors are located in about 70 percent. in the digestive tract and up to 30 percent. in the respiratory system. They constitute only 2 percent. tumors of a given organ.
Neuroendocrine tumors: hormonally active and hormonally inactive
Neuroendocrine tumors can secrete hormonal compounds, then they are called hormonally active. A significant proportion of these tumors do not produce enough hormones and / or biogenic amines to exhibit clinical symptoms, which is why they are called non-functional tumors.
Neuroendocrine tumors: carcinoids
Carcinoid tumors are the most common gastrointestinal tumorsentero-pancreatic. They account for half of all NET tumors. In 90% of cases, these tumors are malignant, but the onset of the disease is asymptomatic. They originate in the small intestine, most often they are cancers of the appendix. Their detection is most often accidental during surgical procedures for other reasons.
Clinical symptoms, and thus the detection of a carcinoid tumor occurs when it is already an advanced form of cancer and metastases appear. Carcinoid tumors secrete serotonin, which causes symptoms called "carcinoid syndrome" - reddening of the skin, diarrhea, difficulty breathing, asthma or wheezing, congestive heart failure, palpitations, abdominal pain, swelling.
Neuroendocrine tumors: insulinoma
Insulinoma is the second most common neuroendocrine tumor. It occurs in 17 percent of the cases. It produces insulin in an uncontrolled manner, which can lead to severe hypoglycaemia, i.e. a significant reduction in blood glucose levels.
The most common symptoms are: headache and dizziness, disturbance in concentration, vision, speech, drowsiness, severe hunger, increased sweating, anxiety and irritability. About 30 percent of people gain significant weight. Due to the non-specific and often periodic occurrence of symptoms, it is detected after several or even several years.
Neuroendocrine tumors: gastrinoma
Gastrinoma - occurs in 5 percent of NET1 cases. It produces gastrin, which leads to the symptoms of persistent peptic ulcer disease. It most often appears as multiple nodules in the duodenal wall (40 percent of gastrinoma cases) or as a single tumor in the pancreas (40 percent of cases).
In most cases it is a malignant neoplasm. Excessive gastrin secretion causes the following symptoms: persistent diarrhea, ulcers in unusual locations - esophagus, intestine.
Neuroendocrine tumors: glucagonoma
Glucagonoma occurs in 2 percent of the time. It is a glucagon-secreting tumor that occurs in the tail of the pancreas as a single, solid lesion, large (up to 25 cm). The first symptom of the disease may be hyperglycaemia.
In addition, the symptoms of glucagonoma are: necrotic skin erythema, abdominal pain, nausea, diarrhea, rapid weight loss, anemia, deep vein thrombosis and pulmonary obstruction.
Neuroendocrine tumors: VIP-oma
VIP-oma is one of the rare neuroendocrine tumors (1 percent) 1. Most often located in the pancreas or retroperitoneal tissue. It secretes a vasoactive intestinal peptide (VIP) that causes a set of symptoms known as pancreatic cholera.
It is characterized by diarrhea with a significant loss of potassium and bicarbonate, hypokalemia (too little potassium) in the blood serum and achloridia (no acid secretion).
Neuroendocrine tumors: somatostatinoma
Somatostatinoma accounts for 1 percent of neuroendocrine tumors. In the great majority of cases (75 percent), a single tumor is located in the head of the pancreas. It secretes somatostatin, a hormone that inhibits the secretion of digestive enzymes. The symptoms of the disease often include diarrhea, enlarged gallbladder, and calcium absorption disorders.
Prof. dr hab. med. Marek Ruchała, Head of the Department and Clinic of Endocrinology, Metabolism and Internal Diseases of the Medical University of Poznań, President of the Polish Society of EndocrinologyThe majority of NET patients, 60 percent. are active hormonal neoplasms. These are serotonin-secreting midguts (carcinoids) and pancreatic tumors of the insulinoma (secreting the hormone insulin) and gastrinomas (secreting the hormone gastrin). They cause the appearance of symptoms in the form of paroxysmal diarrhea, redness of the face, or attacks of hypoglycaemia and recurrent gastric and duodenal ulcer disease.
These non-specific symptoms often result in misdiagnosis (irritable bowel syndrome, reactive hypoglycemia or menopause), which significantly extends the diagnostic process, often up to 5-7 years.