Neuroendocrine tumors G2 refers to highly differentiated neuroendocrine carcinomas, which are a series of tumors that originate from neuroendocrine organs or cells in the body. Common sites of origin include the pancreas, thyroid, parathyroid, and adrenal glands, pituitary gland, and gastrointestinal tract silver cells. Certain neuroendocrine tumors can produce prostaglandins, amino acids, and peptide hormones, resulting in specific hormonal syndromes. For highly differentiated neuroendocrine carcinomas, the histological characteristics show better tissue differentiation, the biological behavior is low malignancy, the KI67 index is 3%-20%, there is often vascular invasion, there may be metastasis, and the prognosis is slightly better. With the improvement of modern technology, new targeted drugs are also applied to neuroendocrine tumors.