Language
Country/Area
No result found
Secrets of the neuroendocrine system: How do these cells affect our health?
Neuroendocrine tumors (NETs) are a type of tumor that arises from cells of the endocrine and nervous systems. These tumors usually develop in the intestines, the most common of which are called Kaposi's tumors, but they can also occur in the pancreas, lungs, and other parts of the body. Although there are many types of NETs, these tumor cells are treated as a group of tissues because they share common characteristics, including similar histological appearance, characteristic secretory granules, and frequent production of substances such as biogenic amines and peptide hormones. The neuroendocrine system includes various endocrine glands, including the pituitary gland, parathyroid glands and neuroendocrine adrenal glands, as well as endocrine islet cells buried in glandular tissue and cells scattered in exocrine gland tissue.
These tumors often display distinct histologic features, including markers of cellular proliferation.
Categories
According to the World Health Organization (WHO) classification, neuroendocrine tumors are divided into three main categories, emphasizing the grade of the tumor rather than the anatomic origin. The three categories are:
- Well-differentiated neuroendocrine tumors of benign and indeterminate behavior
- Low-grade well-differentiated neuroendocrine carcinoma
- High-grade poorly differentiated neuroendocrine carcinoma
The grade of these tumors is assessed based on specific histologic features such as size, lymphovascular invasion, and mitotic count. According to the 2022 WHO update, the grading system for NETs emphasizes the assessment of cell proliferation and is divided into three grades:
- G1 (low grade)
- G2 (intermediate grade)
- G3 (High Grade)
Tumor necrosis is considered a potential poor prognostic factor but is not included in the grading of some tumors.
Anatomical distribution
Neuroendocrine tumors have traditionally been classified according to the anatomical site of their origin. NETs can appear in many different parts of the body, but are most common in the intestines, pancreas, and lungs. The cells of these tumors originate from endocrine glands and are scattered throughout the body, especially Kulchitsky cells in the intestinal tract and pulmonary system.
Neuroendocrine tumors include certain digestive tract tumors and pancreatic islet cell tumors.
Symptoms and Diagnosis
Symptoms of NETs can vary depending on the tumor's origin and the hormones it secretes. For example, a Kassler tumor in the intestine may cause neck flushing, abdominal pain, and lung disease. Neuroendocrine tumors of the pancreas may cause greasy stools or low blood sugar. Many tumors may have already spread by the time they are discovered, and testing is often accompanied by tests for tumor markers, such as chromatin A and neuron-specific enolase, to assist in the initial diagnosis.
Treatment methods
For the treatment of NETs, multiple factors need to be considered, including tumor location, invasiveness, hormone secretion, and metastasis. Treatments may include surgery, radiation therapy, and chemotherapy, aimed at eliminating the disease or relieving symptoms. Observation may be a viable option for nonfunctional low-grade neuroendocrine tumors. If the tumor is locally advanced or has metastasized but is slow growing, symptom palliation is usually preferred over immediate surgery.
In the management of neuroendocrine tumors, in addition to the treatment of individual tumor types, screening for genetic disorders cannot be ignored. These tumors may occur in certain familial syndromes, such as multiple endocrine neoplasia (MEN) and Von Hippel-Lindau (VHL) disease. Regular monitoring and early intervention are key steps in preventing and treating neuroendocrine tumors.
How does the functioning of the neuroendocrine system affect our health and life? Is it worthy of our further understanding and attention in our daily lives?
