Gastric cancer is one of the common malignant tumors, and in China, its incidence rate is the second highest among malignant tumors and mortality rate is the first among all kinds of cancers. The national annual mortality rate is 20.93/100,000 population for men and 10.16/100,000 population for women, with the ratio of men to women being 2.5-3 to 1. Stomach cancer can occur at any age, mostly between 40-69 years old. Due to the rapid development of gastric cancer, more than 90% of patients will die within one year if they do not undergo surgery after symptoms appear. In recent years, with the improvement of surgical methods and the application of comprehensive treatment, the cure rate of gastric cancer has been improved, but most of the reported 5-year survival rate is still 20%-30%.
Causes of gastric cancer
The exact cause of development is still unclear, and the factors that may be related are
1.Genetic factors: The family clustering of gastric cancer has been shown by some researches, mainly related to blood relationship (such as parents and siblings), followed by common life history.
2.Stomach disorders: Certain diseases of stomach such as gastric polyps, gastric ulcer, chronic atrophic gastritis, intestinal epithelial metaplasia, etc. are considered by some scholars as possible precancerous lesions.
3.Dietary habits: residents in areas with high incidence of stomach cancer eat a lot of high-salt foods such as smoked dried meat, salted fish, fish sauce and crab paste, which have been proved to have a catalytic effect on the occurrence and development of stomach cancer. Preferring hot and hot food, fast food, irregular meals and smoked and salted food may cause damage to the gastric mucosa and become a cause of gastric cancer.
4.Nitrosamines: Since nitrosamines have strong carcinogenicity and have been proved to induce gastric cancer in animal experiments, and the predecessor of this compound – secondary amines and nitrites are widely distributed in nature and can be synthesized under suitable acidity (such as the acidic environment in the stomach) or the action of bacteria, nitrites are likely to be one of the causative factors of human gastric cancer. If fresh vegetables are left for a few days, the nitrite content will rise sharply; when vegetables are cooked, they do not contain much nitrite, but their content will rise significantly after overnight, especially cabbage, so it is better not to always eat leftover vegetables; in addition, the nitrite content of cooked meat such as bacon is also high.
Common symptoms of gastric cancer
Early gastric cancer mostly has no obvious symptoms, but with the development of the disease, some discomfort may appear gradually, but even in late stage patients, the symptoms are diverse, similar to those of gastritis or gastric ulcer, such as: upper abdominal pain or fullness, wasting, loss of appetite and vomiting, vomiting blood or black stool are the most common, some cases have no obvious digestive symptoms, but the symptoms of abdominal mass or metastases are the first symptoms.
Who should be alert to the risk of stomach cancer
1.Unexplained loss of appetite, epigastric discomfort, wasting especially for middle-aged patients or above.
2.Patients with unexplained vomiting blood, black stool or positive fecal occult blood.
3, the original history of long-term chronic gastric disease, the recent symptoms have significantly aggravated.
4.Middle-aged people with no previous history of gastric disease and with short-term gastric symptoms.
5.Patients who have been diagnosed with gastric ulcer, gastric polyp or atrophic gastritis should be followed up and reviewed regularly. Usually, gastroscopy should be done once every six months to a year.
6.Patients who had a major gastrectomy for benign gastric disorders many years ago and have recently developed gastrointestinal symptoms.
7.Patients with epigastric pain, fullness, tension or palpable mass.
8.Lymph nodes in the supraclavicular fossa are enlarged.
Patients with the above symptoms should seek medical consultation in time to avoid delaying the disease and losing the opportunity of treatment.
Treatment of gastric cancer
Radical surgery to remove the tumor is the most important and the only possible curative treatment. Depending on the location, growth and infiltration of the tumor, you can choose to have a major gastrectomy (i.e. preserving about 1/4 of the stomach tissue) or a total gastrectomy (removing the whole stomach and anastomosing the esophagus and jejunum). This is supplemented by chemotherapy and immunotherapy. No matter which surgical method is adopted (preserving or not preserving part of the stomach), after proper postoperative conditioning and recovery, patients can gradually restore the quality and quantity of normal food intake.
Prognosis of gastric cancer
The 5-year survival rate of gastric cancer mentioned earlier is usually only 20-30%, referring to the overall level of all gastric cancers. Due to the lack of attention to gastric cancer, some patients are already advanced gastric cancer when they are diagnosed, and the prognosis is extremely poor, and few of these patients survive for more than five years; while the five-year survival rate of early gastric cancer (tumor cells only infiltrate to the mucosal layer) can be as high as 90% or more after surgery, but these patients usually have no symptoms and are extremely difficult to detect, and even in the United States, only 10%-15% of gastric cancer can be diagnosed early; progressive gastric cancer After radical resection, the five-year survival rate of gastric cancer generally ranges from 15% to 50%, depending on the degree of tumor infiltration, malignancy and the degree of surgical cure. Therefore, early detection and early treatment are the only guarantee to improve the survival rate of gastric cancer.