Small intestinal carcinoid

　Small intestinal carcinoid originates from the cells of the intestinal wall acinar glands and is a tumor that can produce small molecular peptides or peptide hormones, that is, APUD cell tumors. Carcinoids have the characteristics of malignant tumor infiltration and growth. The infiltration of cancer destroys the mucosal layer, muscular layer, serosal layer, and surrounding fatty connective tissue, and can infiltrate into lymphatics and blood vessels to cause distant metastasis.

　　In addition to its clinical manifestations, small intestinal carcinoid can also cause other diseases. Intestinal obstruction, intussusception, endocardial fibrosis, asthma, and other complications are common in small intestinal carcinoid, which should be highly regarded by both clinicians and patients.

　　The clinical manifestations of small intestinal carcinoid are the same as those of general small intestinal tumors. Patients may be asymptomatic or have unobvious gastrointestinal symptoms. Due to the rarity of mucosal ulcers, intestinal bleeding is rare. A few patients may appear with symptoms of intestinal obstruction. The most common symptoms of small intestinal carcinoid are symptoms such as flushing, diarrhea, wheezing, right heart valve disease, and pellagra. The appearance of carcinoid syndrome often indicates the spread of carcinoid, which should be highly regarded.

　　Patients with small intestinal carcinoid may be asymptomatic or have unobvious gastrointestinal symptoms. Due to the rarity of mucosal ulcers, intestinal bleeding is rare. A few patients may appear with symptoms of intestinal obstruction. Currently, there are no effective preventive measures for this disease, and early detection and early diagnosis are the key to its prevention and treatment.

　　The preoperative diagnosis of small intestinal carcinoid is not easy. When there is unexplained gastrointestinal bleeding, anemia, recurrent abdominal pain, and suspected small intestinal tumor, the possibility of the disease should be considered. If accompanied by the symptoms of carcinoid syndrome, one should be more vigilant about small intestinal carcinoid. For suspected cases, appropriate examinations should be performed as follows:

　　1. Urine examination

　　The 24-hour urine 5-HIAA determination is of great significance if it is greater than 30mg/day. A qualitative diagnosis can be made basically when it is greater than 50mg/day.

　　2. Selective superior mesenteric artery angiography

　　Angiography can show the size of the tumor, bleeding conditions, and the number of lesions.

　　3. Fiberoptic small intestinal endoscopy

　　Colonoscopy can directly observe the presence of bleeding and tumor conditions in the small intestine and perform biopsies.

　　4. Ultrasound and CT scans

　　Ultrasound and CT scans are more valuable for diagnosing liver metastasis in carcinoid.

　　In terms of diet, the following points should be noted for small intestinal carcinoid patients:

　　1. Diet should be regular and quantitative, with fewer meals and more snacks.

　　2. Eat more foods rich in vitamin A, C, and E, and eat more green vegetables and fruits.

　　3. Often eat foods containing substances that can inhibit carcinogenic effects, such as kohlrabi, cabbage, carrots, rapeseed, garlic, vegetable oil, fish, etc.

　　4. Do not eat salted, smoked, roasted, and fried foods.

　　5. Adhere to a low-fat diet, often eat some lean meat, eggs, and yogurt.

　　Food should be fresh, and moldy and deteriorated food should not be eaten.

　　The main treatment methods for small intestinal carcinoid include the following:

　　1. Surgical treatment

　　Surgical treatment is the main method for small intestinal carcinoid. If the primary lesion can be removed early, surgical treatment is the most effective method. Since the removal of functional carcinoid tissue is the most effective way to relieve carcinoid syndrome, even if there is a suspicion of metastasis, the opportunity for surgery should be seized and active surgical treatment should be carried out.

　　2. Chemotherapy

　　Carcinoid is generally insensitive to chemical drugs. For patients with liver and other organ metastases, chemotherapy can be tried. Common drugs include fluorouracil (5-Fu), doxorubicin (adriamycin), and streptozocin.

　　3. Treatment for carcinoid syndrome

　　Commonly used drugs for the treatment of carcinoid syndrome include 5-HT synthesis inhibitors, 5-HT antagonists, kallikrein inhibitors or antagonists.

　　4. Supportive therapy

　　During treatment, patients should be given high-nutrition, high-calorie diets, and actively supplement vitamins and proteins. Anemia patients can receive blood transfusions. In cases of hypotension, blood volume should be first supplemented without using sympathomimetic drugs.

　　5. Symptomatic treatment

　　Symptomatic treatment can be given during diarrhea and asthma attacks. Patients with heart failure should be treated with digitalis and diuretics.

　　6. Radiation therapy

　　Radiation therapy is effective for pain caused by bone metastasis, with a total dose of about 40-45 Gy.