Gastrointestinal stromal tumor
Introduction
Introduction to gastrointestinal stromal tumors Gastrointestinal Stromal Tumors (GISTs) are a type of tumor that originates from the mesenchymal tissue of the gastrointestinal tract and accounts for most of the tumors of the digestive tract. As a newer concept, stromal tumors should cover the so-called "gastrointestinal leiomyomas" or "gastrointestinal leiomyosarcoma", but as tumors of mesenchymal tissue, gastrointestinal leiomyoma or sarcoma The concept has not been ruled out, except in the current clinical pathological diagnosis, these tumors account for only a small part of the gastrointestinal mesenchymal tumors. No specific clinical manifestations, the course of disease can be as short as several days to 20 years, the course of malignant GIST is shorter, more than a few months, benign or early asymptomatic. The main symptoms of GIST depend on the size and location of the tumor and are usually non-specific. Gastrointestinal bleeding is the most common symptom. The symptoms of swallowing discomfort and dysphagia in the GIST of the Tuen Mun Department are also common. Some patients with perforation of ulcers can increase the risk of abdominal implants and local recurrence. Common symptoms include abdominal pain, mass and gastrointestinal bleeding, and gastrointestinal obstruction. Ascites can occur in the abdominal cavity, and malignant GIST can have symptoms such as weight loss and fever. basic knowledge The proportion of illness: the incidence rate is about 0.0005% - 0.0007% Susceptible people: more common in middle-aged and elderly patients Mode of infection: non-infectious Complications: colorectal injury mesenteric tumor retinal tumor stomach tumor small intestine tumor
Cause
Causes of gastrointestinal stromal tumors
Environmental factors (40%):
Environmental factors are an important factor in the generation of gastric stromal tumors. The etiology of gastric stromal tumors is closely related to the eating habits of various places. Frequent consumption of mildew, pickled, smoked and other foods, or excessive intake of salt, may increase the risk of gastric stromal tumors. Smoked fish contain more 3,4-benzopyrene, moldy foods contain many mycotoxins, and pickled foods contain nitrous acid, which are carcinogenic. Therefore, everyone must develop good habits, refuse junk food, and eat more fruits and vegetables.
Genetic factors (20%):
Studies have shown that the etiology of gastric stromal tumors is also related to heredity. The incidence of gastric stromal tumors in patients' families is higher than that of the average person. These people may be due to similar living environment and eating habits, which increases the incidence of gastric stromal tumors. Opportunity, which also indicates that genetic factors play an important role in the pathogenesis of gastric stromal tumors.
Gastrointestinal mesenchymal tumors are only a minority in gastrointestinal tumors, but they are numerous and complex in morphology. In the past, due to pathological techniques, many gastrointestinal tract tumor cells with smooth muscle fibers or nerve bundles were found. Often diagnosed as smooth muscle-derived tumors or neurogenic tumors, most of the studies now consider that most of them are c-kit-positive or CD34-positive mesenchymal cells of the interstitial cells of Cajal (ICC), ie The current definition of gastrointestinal stromal tumors, while smooth muscle-derived or neurogenic tumors account for only a very small number.
Prevention
Gastrointestinal stromal tumor prevention
Strengthen physical exercise, enhance physical fitness, and exercise more in the sun. Excessive sweating can excrete acidic substances in the body with sweat, avoiding the formation of acidic body.
Have a good attitude to cope with stress, work and rest, do not fatigue. Visible pressure is an important cause of cancer. Chinese medicine believes that stress leads to excessive physical weakness, which leads to decreased immune function, endocrine disorders, metabolic disorders in the body, leading to the deposition of acidic substances in the body. Stress can also lead to mental stress causing qi stagnation and blood stasis. Invagination and so on.
Don't eat too much salty and spicy food, don't eat food that is overheated, too cold, expired and deteriorated; those who are frail or have certain genetic genes should eat some cancer-preventing foods and alkaline substances with high alkalinity as appropriate. Food, maintain a good mental state to develop good habits, stop smoking and limit alcohol. Smoking, the World Health Organization predicts that if people no longer smoke, after five years, the world's cancer will be reduced by 1/3; secondly, no alcohol. Smoke and alcohol are extremely acidic and acidic substances. People who smoke and drink for a long time can easily lead to acidic body. Finding timely treatment of the disease is key.
Complication
Gastrointestinal stromal tumor complications Complications colorectal injury mesenteric tumor retinal tumor gastric tumor small intestine tumor
Gastrointestinal stromal tumors account for 1 to 3% of gastrointestinal malignancies. The estimated annual incidence rate is about 10-20/1 million. It is more common in middle-aged and elderly patients. Patients under 40 years old are rare, and there is no significant difference in the incidence rate between men and women. Most of GIST occurs in the stomach (50-70%) and the small intestine (20-30%), the colorectal accounts for about 10-20%, and the esophagus accounts for 0-6%. It is rare after the mesentery, omentum and abdominal cavity. 20-30% of patients with GIST are malignant. About 11% to 47% of patients have metastasized at the first visit, and the metastasis is mainly in the liver and abdominal cavity. Common complications of gastrointestinal stromal tumors; the overall 5-year survival rate of prognosis GISTs is 35%, the 5-year survival rate of complete tumor resection is 50-65%, and the survival time of unresectable patients; lt; 12 months, tumor location, size The number of mitotic divisions and age were associated with prognosis. The prognosis of guts in GSTs was the best, while the prognosis of small intestine GISTs was the worst.
Symptom
Gastrointestinal stromal tumor symptoms Common symptoms Dysphagia Gastrointestinal bleeding Difficulty swallowing Intestinal perforation Swallowing pain
Clinical manifestation
GISTs are the most common mesenchymal tumors in the gastrointestinal tract, accounting for 1 to 3% of gastrointestinal malignancies. The estimated annual incidence is about 1 to 2/10000, which is more common in middle-aged and elderly patients, and less common in patients under 40 years old. There is no significant difference in the incidence of male and female. Most GISTs occur in the stomach (50-70%) and the small intestine (20-30%), the colorectal accounts for about 10-20%, the esophagus accounts for 0-6%, the mesentery, the omentum and the abdominal cavity. After the rare.
The symptoms of GISTs depend on the size and location of the tumor. They are usually non-specific. Gastrointestinal bleeding is the most common symptom. In the esophagus, dysphagia is often common. Some patients have perforation due to intestinal perforation, which can increase abdominal implantation and local recurrence. risks of.
About 11% to 47% of patients with GISTs have metastases at the first visit. The metastases are mainly in the liver and abdominal cavity. Lymph nodes and extra-abdominal metastases are rare even in more advanced patients. Metastases may even occur after primary tumor resection. In 30 years, small intestine GISTs have the highest degree of malignancy and lymph node metastasis, while esophage GISTs have a low degree of malignancy. Therefore, strictly speaking, GISTs are not benign, or at least one type of malignant tumor including potential malignancy.
CT, endoscopic ultrasonography, and gastrointestinal angiography can assist in the determination of GISTs size, local infiltration, metastasis, and location.
Examine
Gastrointestinal stromal tumor examination
1. Physical examination: Some patients with large tumors can reach the abdominal mass, smooth surface, nodules or lobulation.
2. Laboratory examination: patients may have anemia, hypoproteinemia, and fecal occult blood positive.
3. Imaging features:
1 gastroscope and ultrasound gastroscopy:
For gastric GIST, gastroscopy can help to identify the location and size of the tumor. Endoscopic ultrasonography can assist in the diagnosis of extrahepatic tumors, and the location, size, origin, local infiltration, and metastasis of GIST. Some patients have a pathological diagnosis.
2CT check:
CT scan revealed that the tumors were mostly round or round, and a few were irregular. Benign tumors are less than 5cm in size, uniform in density, sharp in edge, rarely invade adjacent organs, and may have calcification. Malignant tumors are more than 6cm, the boundary is unclear, and it is afflicted with adjacent organs. It can be lobulated, density is uneven, and the center is prone to necrosis, cystic changes and hemorrhage. Tumors can be mixed with high and low density, and calcification is rare. Enhanced CT showed uniform uniform density and more uniform moderate or significant enhancement, spiral CT showed obvious in the venous phase. This kind of strengthening is more common in low-grade malignant gastrointestinal stromal tumors. Necrosis and cystic changes often show obvious enhancement around the tumor. Three-dimensional reconstruction of CT digestive tract can assist diagnosis of tumors, and coordinate the location, size, local infiltration, and metastasis of GIST.
318FDG-PET and 18FDG-PET/CT: CT, MRI and other imaging methods only evaluate the size of the tumor, the density of the tumor and the distribution of blood vessels in the tumor, and can not reflect the metabolism of the tumor. PET examination with 18-fluorodeoxyglucose can make up The above physics examination is insufficient. Its principle is that the gastrointestinal stromal tumor is a highly metabolized tumor. It uses the strong glycolytic reaction in the tumor to ingest high-density 18-fluorodeoxyglucose to track and develop, and to metastasize or relapse early. It is more sensitive than CT and is superior to other physical examination methods in evaluating the response of tumors to chemotherapeutic drugs. PET and CT combined scanning methods can simultaneously evaluate the anatomy and metabolism of tumors, and better evaluate the staging and treatment effects of tumors. CT also provides a reference for the judgment of the efficacy of other solid tumor molecular targeted therapies.
4 other auxiliary inspections:
The X-ray meal shows that the edges are neat and round, and the center may have a "umbilical" ulcer, or it may be compressed or displaced. The superior mesenteric artery DSA is of great significance for the diagnosis and tumor localization of small intestine GIST.
Diagnosis
Diagnosis and diagnosis of gastrointestinal stromal tumors
GISTs often need to be identified with the following tumors, which often have clinical manifestations similar to GISTs.
1, gastrointestinal leiomyomas / sarcoma GISTs mostly diffuse positive expression of CD117 and CD34, SMA does not express or focal expression, while leiomyomas / sarcoma CD117 and CD34 negative expression, SMA diffuse positive expression.
2. S-100 expression was found in a small number of cases of gastrointestinal schwannomas GISTs, while gastrointestinal schwannomas S-100 was diffusely positive, and CD117 and CD34 were negative.
3, gastrointestinal autonomic neuroma CD117, CD34, S-100, SMA and Desmin were negative expression, neurosecretory granules were observed under electron microscope.
Judging the malignant degree of GISTs In addition to clinical local infiltration, metastasis, recurrence and other factors, the tumor site is also a consideration. Generally speaking, the GISTs of the stomach, esophagus and rectum are less malignant, while the small intestine and colon are more malignant. The size of the tumor and the number of mitotic divisions are also one of the criteria for judging the degree of malignancy of GISTs (see table below).
Judgment of malignant degree of table GISTs
Malignant degree tumor size (maximum diameter, cm) number of mitotic divisions / 50HPF
Low
Stomach 5 5
Small intestine 2 2
Moderate
Stomach 5~10 5
Small intestine 2~5 5
Height
Stomach >10 >5
Small intestine>5 >5
Note: Both tumor size and number of nuclear divisions must be met.
There is a match between the tumor size and the number of mitotic divisions.
