Gastric cancer is the most common cancer of the digestive tract. According to autopsy data from 28 medical schools in mainland China, gastric cancer ranks first among malignant tumors of the digestive tract and third among all cancers. It most commonly occurs in people aged 40 to 60, but cases in those under 40 still account for 15% to 20% of all cases. The disease is more common in men than in women, with a ratio of approximately 3:1. In mainland China, the incidence of gastric cancer is highest in the Northwest, followed by the Northeast and Inner Mongolia, then North China and East China, while it is lowest in Central-South and Southwest China. The highest incidence rate can reach 40.6 per 100,000 people, while the lowest is below 5 per 100,000. Countries with high incidence rates of gastric cancer include Japan, Chile, Finland, and Russia.
Gastric cancer is often classified under the categories of “reverse stomach” (fanwei), “epigastric pain” (weiguantong), and “mass accumulation” (jiju) in traditional Chinese medicine.
I. Risk Factors for Gastric Cancer
The exact causes of gastric cancer have not yet been fully elucidated, but current research by scholars both domestically and internationally suggests a close relationship with the following factors:
External factors: diet, eating habits, occupation, lifestyle choices (such as smoking and alcohol consumption), and environmental conditions, including soil quality. Among these, diet is the most significant factor. It has been reported that nitrosamines are potent carcinogens; they are present in soil and water and can accumulate in vegetables. In the stomachs of both humans and animals, nitric acid can be synthesized from secondary amines and nitrites. Fish contains secondary amines, while some meat preservatives contain nitrites. If these two types of food are consumed simultaneously, carcinogenic nitrosamines can form in the stomach. Animal studies have shown that even small daily doses of nitrites can pose a cancer risk if ingested over a sufficiently long period.
Internal factors: Genetics, blood type, constitution, and ethnicity are also closely related to the development of gastric cancer.
The incidence of gastric cancer among relatives of gastric cancer patients is four times higher than in the general population; among Caucasians, the incidence of gastric cancer is higher in those with blood type A; gastric cancer is more common in people with a weak constitution; and statistics show that the incidence of gastric cancer is higher among African Americans than among Caucasians.
Conditions Prone to Malignancy: For example, gastric ulcers are prone to becoming cancerous, and the rate of malignant transformation is higher for antral ulcers than for corpus ulcers; chronic atrophic gastritis can progress to gastric cancer; gastric polyps are benign adenomas, but larger polyps can develop into gastric cancer.
Traditional Chinese Medicine holds that a deficiency of “ Zhengqi ” (vital energy) is an internal factor in tumor formation. The onset of gastric cancer is often associated with deficiency of qi and blood and damage to the spleen and stomach. Against this backdrop, emotional disturbances and irregular dietary habits lead to qi stagnation and blood stasis, which, over time, develop into disease and result in this condition.
Gastric cancer can occur in any part of the stomach, but it is most common in the antrum, followed by the lesser curvature, and then the cardia; it is less common in the greater curvature and the anterior wall.
II. Metastasis of Gastric Cancer
The routes of metastasis for gastric cancer include:
① Direct spread: Gastric cancer can infiltrate the surrounding or deeper layers of the gastric wall; it can directly invade the abdominal wall, adjacent organs, and tissues—such as the liver, pancreas, spleen, greater omentum, and transverse colon mesentery—and can also spread along the lymphatic network in the submucosal layer, invading the lower esophagus upward and the duodenum downward.
② Lymphatic Metastasis: This is the primary mode of metastasis for gastric cancer. After cancer cells invade the lymphatic vessels, they form emboli and are carried by lymphatic fluid to regional lymph nodes, including the supra-pyloric, lesser curvature, and infra-pyloric lymph nodes.
③ Hematogenous spread: This typically occurs in advanced stages, with cells spreading via the bloodstream to the liver, lungs, bones, brain, skin, and even the ovaries.
④ Intraperitoneal seeding: As the tumor infiltrates and penetrates the gastric wall, cancer cells detach and seed the peritoneum, omentum, or the surfaces of other organs.
III. Clinical Manifestations
In patients with early-stage gastric cancer, clinical symptoms are often atypical and subtle, resembling those of peptic ulcers or chronic gastritis. Common symptoms include upper abdominal discomfort, dull pain, belching, acid reflux, loss of appetite, and mild anemia.
As the disease progresses, gastric symptoms become increasingly pronounced, including upper abdominal pain, loss of appetite, and weight loss. Symptoms may also vary depending on the location of the tumor. For example, cancers located in the cardia or the upper lesser curvature of the stomach may cause a sensation of food obstruction that progressively worsens; When cancer in the gastric antrum reaches a certain size, it may cause partial or complete pyloric obstruction. In such cases, patients may experience a sensation of fullness in the upper abdomen and vomiting; the vomit often consists of food from the previous day or gastric juice. Sometimes patients become too afraid to eat. If the tumor ulcerates or invades adjacent blood vessels, it may lead to bleeding, manifesting as blood in the stool or hematemesis, or it may result in acute gastric perforation.
In advanced gastric cancer, a mass may be palpable in the upper abdomen, or symptoms caused by metastasis may appear, such as hepatomegaly, jaundice (when the tumor directly compresses the common bile duct or when enlarged hilar lymph nodes from metastasis compress the common bile duct), ascites, and supraclavicular lymphadenopathy. At this stage, marked cachexia is already present.
During physical examination, early-stage gastric cancer often presents no physical signs, whereas in advanced stages, a mass may be palpable in the upper abdomen; it is typically nodular, firm, and slightly tender. When a mass is palpated, attention should be paid to its location, size, number, nature (cystic or solid), shape, whether the surface is smooth, degree of mobility, and presence of tenderness. A digital rectal examination can determine whether there are metastases in the anorectal region.
IV. Diagnosis of Gastric Cancer
Diagnosing advanced gastric cancer is not difficult; however, early-stage gastric cancer presents with subtle symptoms that are easily overlooked by both patients and healthcare providers. Treatment outcomes for early-stage gastric cancer are significantly better than those for advanced-stage gastric cancer. Therefore, early detection and timely treatment are currently considered key to improving cure rates. To facilitate early detection of gastric cancer, the following points are crucial:
Any patient over the age of 40 with no prior history of gastric disease who has recently experienced upper abdominal discomfort, dull pain, belching, or loss of appetite—or who has a history of chronic peptic ulcer disease with a recent significant worsening of symptoms, or a change in the pattern of pain—must not be casually dismissed as having a “mild condition”; a comprehensive and detailed examination is essential.
For individuals with precancerous gastric lesions—such as reduced or absent gastric acid secretion, atrophic gastritis, gastric ulcers, or gastric polyps—regular, systematic examinations or prompt, early, and active treatment should be conducted to prevent cancer development.
Improving the early diagnosis rate of gastric cancer primarily depends on the advancement and comprehensive application of diagnostic methods. Barium meal X-ray examinations, fiber-optic gastroscopy, and gastric fluid cytology are currently the three key diagnostic tools. The combined use of these three methods can raise the early diagnosis rate of gastric cancer to 98 percent. Gastroscopy allows for direct observation of the tumor’s location, extent, and morphology, and also enables biopsy.
V. Treatment of Gastric Cancer
Surgical Treatment: To date, radical surgery remains the most effective treatment for gastric cancer, particularly early-stage gastric cancer. The principle of radical surgery is to perform a total gastrectomy or subtotal gastrectomy based on the tumor’s location, along with resection of the greater and lesser omentum and regional lymph nodes, followed by reconstruction of the digestive tract. For patients with advanced gastric cancer who are not candidates for curative surgery but have pyloric obstruction, every effort should be made to perform a gastorojejunal anastomosis to resolve feeding issues and prolong life.
Chemotherapy: This method inhibits the spread of cancer cells and kills residual cancer cells to prevent recurrence. It is used as an adjunct to surgery and is administered before, during, and after surgery. For patients who are inoperable, chemotherapy drugs serve a palliative role. Commonly used anticancer drugs include 5-fluorouracil, mitomycin, cyclophosphamide, 5-fluorouracil, and cisplatin. Combining anticancer drugs yields better results than using them alone.
Herbal Medicine Treatment: Cancer is a systemic disease affecting the entire body, caused by various factors that disrupt the balance of yin and yang and lead to functional abnormalities in the internal organs. Herbal medicine can improve the patient’s overall condition and enhance the body’s resistance to disease. The guiding principles for treatment are as follows: in the early stages of cancer, the focus is generally on eliminating pathogenic factors, supplemented by strengthening the body’s vital energy; in the intermediate stages, both attacking and tonifying approaches are employed; and in the advanced stages, the primary focus is on strengthening the body’s vital energy, supplemented by eliminating pathogenic factors.
Common therapeutic methods for expelling pathogenic factors include regulating qi and subduing counterflow, promoting blood circulation and resolving stasis, resolving phlegm and softening hard masses, and clearing heat and detoxifying. Common therapeutic methods for strengthening the body’s vital energy include tonifying qi and strengthening the spleen, warming the kidneys and invigorating yang, nourishing yin and replenishing blood, and nourishing yin and generating body fluids. These methods can be selected based on the specific condition.
In summary, the use of traditional Chinese herbal medicine after gastric cancer surgery or during chemotherapy can yield good results. The formula “Shiquan Dabu Tang” (Ten-Ingredient Great Tonifying Decoction), with appropriate modifications, is commonly used for treatment.