Intestinal tumor

　　The incidence of tumors occurring in the duodenum, jejunum, and ileum, etc., in intestinal tumors is about 36%, accounting for about 0.2% of all tumors. The low incidence may be related to the following factors:

　　1. The contents of the small intestine are in a liquid state, which can reduce the concentration of carcinogens entering the small intestine.

　　2. The small intestine empties quickly, reducing the contact time between carcinogens and the small intestine.

　　3. The small intestine contains protective acid and high concentrations of immunoglobulin IgA, which may have a solubilizing effect on carcinogens.

　　4. The small intestine may have a special protective system similar to the spleen, which plays a defensive role against tumors.

　　Small intestinal tumors can occur at any age, generally seen in middle-aged and elderly people, most common between 50 to 70 years old, with approximately equal incidence rates between males and females.

　　In small intestinal tumors, malignant tumors are more common than benign tumors. Benign tumors are commonly smooth muscle tumors, lipomas, and adenomas. Hemangiomas are relatively rare, while neurofibromas, fibromas, and fibromyomas are even rarer. Malignant tumors include malignant lymphoma, adenocarcinoma, and leiomyosarcoma, which are more common. Tumors can occur at any part of the small intestine, with adenomas and carcinoids most commonly seen in the duodenum, and other tumors more commonly seen in the ileum and jejunum. Tumors are usually solitary, but they can also be multiple. Multiple lesions of malignant tumors are often due to metastasis from extraintestinal primary lesions.

　　Intestinal tumors can be complicated with intestinal obstruction, intestinal perforation, peritonitis, gastrointestinal bleeding, and anemia. The specific treatment methods are described as follows.

　　1. Intestinal Obstruction:One-third of the patients may develop intestinal obstruction. It is usually chronic incomplete intestinal obstruction with not very significant vomiting and abdominal distension. The characteristic is that intestinal obstruction can recur and resolve spontaneously.

　　2. Intestinal Perforation and Peritonitis:The incidence rate is 8.4% to 18.3%. Some cases occur on the basis of intestinal obstruction, while others are caused by ulcers, necrosis, and infection due to tumor invasion of the intestinal wall, leading to intestinal perforation. Acute perforation can cause diffuse peritonitis with extremely high mortality. Chronic perforation may lead to adhesion between intestinal loops, inflammatory masses, abscesses, and intestinal fistulas.

　　3. Gastrointestinal bleeding and anemia:The incidence rate is 18.1% to 27.9%, common in submucosal tumors. The cause of bleeding is mainly due to erosion, ulceration, and necrosis of the tumor surface. In the case of long-term hidden bleeding, patients may develop anemia.

　　Intestinal tumors include small intestinal tumors and colon cancer, with different clinical manifestations, as described below.

　　Firstly, the clinical manifestations of small intestinal tumors are very atypical, often showing one or more of the following symptoms.

　　1. Abdominal pain is the most common symptom, usually caused by tumor stretching, intestinal peristalsis dysfunction, and other factors, and can be dull, bloating, or even severe colicky pain. When complicated with intestinal obstruction, the pain is especially severe. It can also be accompanied by diarrhea, loss of appetite, and other symptoms.

　　2. Intestinal bleeding is often intermittent, manifesting as blackish tarry stools or hematochezia, even massive bleeding. Some may not be detected due to long-term repeated small amounts of bleeding and manifest as chronic anemia.

　　3. The most common cause of acute intestinal obstruction is intussusception, but most are chronic recurrent. Intestinal stricture and compression of adjacent intestinal tubes caused by tumors are also causes of intestinal obstruction, and can also induce intussusception.

　　4. Intraperitoneal mass generally has a greater degree of mobility, and the location is often not fixed.

　　5. Intestinal perforation is more common in malignant intestinal tumors. Acute perforation leads to peritonitis, while chronic perforation forms an intestinal fistula.

　　6. Carcinoid syndrome is caused by the activation substances kinins produced by carcinoid cells and the substance serotonin. The main manifestations are paroxysmal facial, neck, and upper trunk skin erythema (dilation of capillaries), diarrhea, asthma, and heart valve disease due to fibrous tissue proliferation. It is often triggered by eating, drinking, emotional excitement, and pressing on the tumor. It is mostly seen in patients with carcinoid and liver metastasis.

　　Secondly, early-stage colon cancer often has no specific symptoms. After development, the main symptoms are as follows.

　　1. Changes in defecation habits and fecal characteristics:It is usually the first symptom to appear. It is mostly manifested as increased frequency of defecation, diarrhea, constipation, blood, pus, or mucus in feces.

　　2. Abdominal pain:It is also one of the early symptoms, often manifested as unclear localization persistent dull pain, or just abdominal discomfort or bloating sensation. When intestinal obstruction occurs, abdominal pain intensifies or becomes intermittent colicky pain.

　　3. Abdominal mass:They are mostly due to the tumor itself, and sometimes may be due to feces accumulation in the proximal intestinal lumen. The mass is usually hard and nodular. In the case of transverse colon and sigmoid colon cancer, there may be certain mobility. If the cancer mass penetrates and develops infection, the mass becomes fixed and there is marked tenderness.

　　4. Intestinal obstruction symptoms:Generally, these are late-stage symptoms of colorectal cancer. They are mostly manifested as chronic low-position incomplete intestinal obstruction. The main symptoms are abdominal distension and constipation, abdominal distension pain or intermittent colicky pain. When complete obstruction occurs, symptoms intensify. In some cases of left colon cancer, acute complete colonic obstruction may be the first symptom to appear.

　　5. General symptoms:Due to chronic blood loss, cancer ulceration, infection, and toxin absorption, patients may experience anemia, weight loss, fatigue, low fever, and other symptoms.

　　In the late stage of the disease, liver enlargement, jaundice, edema, ascites, rectal anterior fossa mass, axillary lymph node enlargement, and cachexia may occur. Due to the different pathological types and locations of the cancer, the clinical manifestations are also different. Generally, right-sided colon cancer is mainly manifested by systemic symptoms, anemia, and abdominal mass. Left-sided colon cancer is characterized by symptoms such as intestinal obstruction, constipation, diarrhea, and hematochezia.

　　There are no effective preventive measures for intestinal tumors. Early detection and early diagnosis are the key to the prevention and treatment of the disease. Pay special attention to the high-risk population for intestinal tumors, as described below.

　　1. Age of onset:Most patients develop the disease after the age of 50.

　　2. Family history:If someone's first-degree relative, such as parents, has had colorectal cancer, the risk of developing the disease in their lifetime is 8 times higher than that of the general population. About a quarter of new patients have a family history of colorectal cancer.

　　3. History of colon disease:Certain colon diseases such as Crohn's disease or ulcerative colitis may increase the risk of colorectal cancer, with a risk 30 times higher than that of the general population.

　　4. Polyps:Most colorectal tumors develop from small precancerous lesions and are called polyps. Villous adenomatous polyps are more likely to develop into cancer, with an opportunity of about 25%; the malignancy rate of tubular adenomatous polyps is 1-5%.

　　5. Genetic characteristics:Some familial tumor syndromes, such as hereditary non-polyposis colorectal cancer, can significantly increase the risk of colorectal cancer, and the onset age is younger.

　　Regular health check-ups for the above population are the key to preventing this disease.

　　The examination of intestinal tumors includes X-ray barium meal, fiberoptic duodenoscopy, fiberoptic colonoscopy, and the specific examination methods are described as follows.

　　1. The diagnosis of small bowel tumors mainly relies on clinical manifestations and X-ray barium meal examination. Due to the atypical clinical symptoms of small bowel tumors, and the lack of early signs and effective diagnostic methods, diagnosis is often delayed. For those with one or more manifestations, the possibility of small bowel tumors should be considered, and further examinations are needed.

　　1. X-ray barium meal examination: For suspected duodenal tumors, elastic duodenal barium meal examination is adopted.

　　2. Fiberoptic duodenoscopy, fiberoptic enteroscopy, and selective arteriography: improve the diagnostic rate of small bowel tumors.

　　3. Due to the elevated 5-hydroxytryptamine in the blood of patients with carcinoid tumors, the determination of 5-hydroxyindoleacetic acid (5-HIAA), a degradation product of 5-hydroxytryptamine in the urine of patients suspected of having carcinoid tumors, is helpful in determining the nature of the tumor.

　　4. Abdominal exploration may be necessary if required.

　　2. Early symptoms of colon cancer are often not obvious and can be easily overlooked.

　　Anyone over 40 with any of the following symptoms should be classified as high-risk:

　　1. First-degree relatives with a history of colorectal cancer.

　　2. History of cancer, intestinal adenoma, or gastrointestinal stroma tumor.

　　3. Positive occult blood test in stool.

　　4. Those with two or more of the following symptoms: mucoid blood stool, chronic diarrhea, chronic constipation, history of chronic appendicitis, and history of mental trauma.

　　For this high-risk group or those suspected of having colon cancer, X-ray barium enema or barium double-contrast contrast examination, as well as colonoscopy, can make an accurate diagnosis. B-type ultrasound and CT scanning are helpful in understanding abdominal masses and enlarged lymph nodes, as well as detecting liver metastasis. About 60% of colon cancer patients have higher serum carcinoembryonic antigen (CEA) levels than normal, but the specificity is not high. It is helpful for judging the prognosis and recurrence after surgery.

　　Patients with intestinal tumors should consume more vitamin-rich foods and less food high in fat, and the specific dietary precautions are described as follows.

　　1. The diet of patients with colorectal cancer after surgery should be varied, without dietary bias or pickiness. Do not consume high-fat diets for a long time, and eat fresh vegetables and cancer-preventing foods rich in vitamins regularly.

　　2. Postoperative patients should supplement vitamin-rich foods in their diet, and choose to drink fruit juice and vegetable soup. It is generally believed that if the daily diet is insufficient in vitamin C, less than 100 milligrams, vitamin C tablets should be added to make up for more than 100 milligrams.

　　3. The bleeding during surgery and the stimulation of surgery increase the secretion of adrenal cortex function, which can all lead to increased potassium excretion in the body, and decreased blood potassium and intracellular potassium concentration. Therefore, it is necessary to pay attention to increasing foods rich in potassium in the diet of postoperative patients, such as meat juice, vegetable soup, and peeled fruits.

　　4. During the surgery, patients often experience varying degrees of blood loss. Some patients, although supplemented with blood transfusions, the blood supplemented by blood transfusions is not as good as that produced by the body's own nutrition. Therefore, the diet of postoperative patients should pay attention to increasing the components that enhance blood supply, such as foods high in protein and iron, such as animal liver, lean meat, poultry eggs, milk, crucian carp, duck soup, longan, silver ear, and turtle meat.

　　6. Postoperative patients often dislike greasy foods. Although supplementing fat is also important for postoperative patients, to prevent destroying the patient's appetite, the diet should be light and low in oil. Using fresh, flavorful sesame oil is better.

　　5. Strengthen physical exercise, enhance physical fitness, and improve cold resistance and body resistance. Cordyceps sinensis is of great help to postoperative recovery. Research has found that cordycepin, contained in cordyceps sinensis, can effectively engulf tumor cells, with an effect 4 times that of selenium. It can also enhance the ability of red blood cells to adhere to tumor cells, and can prevent tumor recurrence and metastasis during chemotherapy and after surgery. Patients should choose cordyceps sinensis with a high content of natural cordycepin, powder it, take 1.5 grams each time, twice a day, and continue for a month to achieve good results in most patients.

　　7. The immunity of cancer patients is low, and it is common for white blood cells to be below normal levels. They can eat some warm-nourishing types of meat, such as mutton, dog meat, deer meat, beef tripe, Eucheuma, chicken, eggs, pigeon meat, and turtle meat.

　　8. Eat small, frequent meals, chew slowly. Provide a diet low in fiber and without stimulation to avoid stimulating wound healing. Maintain mental calmness and emotional stability during meals. Eat 6 to 7 meals a day, separate dry and liquid foods, and drink beverages or water 30 minutes after eating.

　　The treatment of intestinal tumors is mainly surgical, and the specific treatment methods are described as follows.

　　First, small intestine tumor

　　Small or pedunculated benign tumors can be locally resected along with the surrounding intestinal wall tissue. For larger or locally multifocal tumors, partial intestinal resection and anastomosis should be performed. For malignant tumors, a radical resection should be performed along with the mesentery and regional lymph nodes. Postoperatively, chemotherapy or radiotherapy should be selected according to the condition. If the tumor has infiltrated and fixed with surrounding tissues and cannot be resected, and there is an obstruction, a bypass operation can be performed to relieve the obstruction.

　　Second, colon cancer

　　The principle is comprehensive treatment with surgery as the main treatment.

　　1. Radical surgery for colon cancer The resection range must include the intestinal loop where the tumor is located, its mesentery, and regional lymph nodes.

　　(1) Right hemicolectomy:It is applicable to cancer in the cecum, ascending colon, and hepatic flexure of the colon. For cecum and ascending colon cancer, the resection range includes the right half of the transverse colon, the ascending colon, and the cecum, including the distal ileum of about 15-20 cm in length, and an end-to-end or end-to-side anastomosis between the ileum and transverse colon should be performed. For cancer in the hepatic flexure of the colon, in addition to the above range, the transverse colon and the lymph node group of the right gastroepiploic artery should be resected.

　　(2) Transverse colon resection:It is applicable to transverse colon cancer. The resection includes the entire transverse colon including the hepatic flexure and splenic flexure, as well as the lymph node group of the gastrocolic ligament, and an end-to-end anastomosis between the ascending and descending colon should be performed. If it is not possible to anastomose due to high tension at both ends, for left-sided transverse colon cancer, the descending colon can be resected, and an anastomosis between the ascending colon and sigmoid colon can be performed.

　　(3) Left hemicolectomy:It is applicable to the sigmoid flexure and descending colon cancer. The resection range includes the left half of the transverse colon and the descending colon, and part or all of the sigmoid colon should be resected according to the height of the descending colon cancer, and then an anastomosis between the colon and rectum should be performed.

　　(4) Radical resection for sigmoid colon cancer:According to the length of the sigmoid colon and the location of the tumor, the entire sigmoid colon and all of the descending colon should be resected, or the entire sigmoid colon, part of the descending colon, and part of the rectum should be resected, and a colorectal anastomosis should be performed.

　　2. For the operation of colon cancer complicated with acute intestinal obstruction, surgery should be performed early after appropriate preparations such as gastrointestinal decompression, correction of water and electrolyte imbalance, and acid-base imbalance. For right-sided colon cancer, a right hemicolectomy with a primary ileocolonic anastomosis can be performed. If the patient's condition does not permit, a colostomy should be performed first to relieve obstruction, and then a radical resection should be performed in the second stage. If the tumor cannot be resected, the distal ileum can be cut off, and the proximal cut end of the ileum can be anastomosed to the transverse colon in a side-to-side manner, and the distal cut end of the ileum can be made into a colostomy. For left-sided colon cancer complicated with acute intestinal obstruction, it is generally recommended to perform a transverse colostomy near the obstruction site, and then perform a radical resection in the second stage after the intestines are fully prepared. For patients with inoperable tumors, a palliative colostomy should be performed.

　　In the specific operation of colon cancer surgery, the proximal and distal ends of the intestinal tract where the tumor is located should first be tightly tied with gauze strips to prevent the spread and implantation of cancer cells in the intestinal lumen. Then, the corresponding blood vessels should be ligated to prevent the hematogenous metastasis of cancer cells; then, the resection of the intestinal loop should be performed.

　　The preoperative preparation for colon cancer surgery is very important. The commonly used methods include oral intestinal antibacterial drugs, laxatives, and multiple enemas:

　　(1) Total intestinal lavage method, start taking oral 37℃左右的等渗平衡电解质液(用氧化钠、碳酸氢钠、氯化钾配制)12-14 hours before surgery, causing voluminous diarrhea to thoroughly clean the intestines. The whole lavage process usually takes about 3-4 hours, and the lavage fluid volume should not be less than 6000ml. Antibacterial drugs can also be added to the lavage fluid. However, this method may not be tolerated by some patients; it is not suitable for the elderly and weak, those with dysfunction of important organs such as the heart and kidneys, and those with intestinal obstruction.

　　(2) Consume liquid diet 2 days before surgery, take intestinal antibacterial drugs (such as neomycin, sulfaguanidine, and metronidazole, etc.) and laxatives (such as 10-30ml of castor oil or 15-20g of magnesium sulfate, once a day), and clean enema the night before surgery.

　　(3) Oral mannitol 5% to 10% method, simpler than the previous method. However, as mannitol is fermented by bacteria in the intestines, it can produce gases that may cause explosion easily when using electrosurgical instruments during surgery, attention should be paid. It should also be used with caution in the elderly and weak, those with poor heart function, and those with dysfunction of important organs such as the heart and kidneys. The above preoperative intestinal preparation measures can empty the colon and reduce the number of bacteria in the intestinal lumen as much as possible, reduce postoperative infection.

　　3. Chemotherapy

　　Chemotherapy, whether adjuvant chemotherapy or tumor chemotherapy, is based on 5-FU. Adjuvant chemotherapy is suitable for patients with Dukes B and C stages after radical surgery, common regimen:

　　(1) 5-FU:450mg/m2 daily, intravenous injection for 5 consecutive days. After an interval of 4 weeks, 450mg/m2 once a week for 48 weeks, while applying levamisole 50mg, 3 times a day, for 3 days every 2 weeks, for a total of 1 year.

　　(2) CF/FU regimen:CF (calcium folinate) 20 or 200mg/m2 × 5 days; 5-FU 450 or 370mg/m2 × 5 days, intravenous infusion, repeated every 4 weeks, a total of 6 courses after surgery.

　　(3) Oral FT-207 (fluorouracil):100-150mg/m2 × 5 days, 3 times a day, total dose of 20-30g.

　　The prognosis of colorectal cancer is good. After radical surgery, the 5-year survival rates for Dukes A, B, and C stages are about 80%, 65%, and 30% respectively.