Early warning of sub-health in digestive system cancers: Screening of high-risk group characteristics for liver cancer, stomach cancer, and colorectal cancer

Section 2 High-Risk Groups for Common Cancers: Sub-healthy Individuals I. High-Risk Groups for Liver Cancer: Sub-healthy Individuals Globally, liver cancer ranks third in cancer mortality, and my country accounts for more than half of the world's liver cancer cases (and deaths). What causes such a high incidence (and mortality) of liver cancer in my country? This relates to the causes of liver cancer. The most widely accepted causes include: ① Chronic infection with hepatitis B, C, and D viruses; ② Aflatoxin; ③ Drinking water contaminated with organic compounds and algal toxins; ④ Familial clustering, low selenium levels, and alcohol consumption. In my country, apart from a few areas where water pollution and dietary habits contribute to high liver cancer rates, the most common cause is chronic hepatitis B, C, and D virus infection, especially chronic hepatitis B virus infection. my country is located in a high-incidence area of ​​viral hepatitis, with approximately 120 million chronic hepatitis B virus carriers and 30 million chronic hepatitis B patients. Hepatitis D virus infection typically occurs on the basis of chronic hepatitis B infection. (1) Patients with chronic viral hepatitis B and hepatitis C, and hepatitis virus carriers. About 90% of patients with primary liver cancer in my country have a background of hepatitis B virus (HBV), while liver cancer in Japan is mainly caused by hepatitis C virus (HCV), and hepatitis D virus (HDV) is prevalent in the former Soviet Union. Chronic hepatitis and cirrhosis are often the basis for the development of liver cancer. (2) People who have the opportunity to eat moldy grains for a long period of time, such as corn and peanuts contaminated with aflatoxin. Studies have shown that the intake of aflatoxin is significantly related to the mortality rate of liver cancer. Aflatoxin and hepatitis B virus have a synergistic carcinogenic effect. (3) People who often drink contaminated water. In areas with a high incidence of liver cancer, such as Nanhui County, Qidong City and Haimen City in Shanghai, surveys show that the mortality rate of liver cancer among those who drink ditch or pond water is significantly higher than that among those who drink well water, and the mortality rate of liver cancer among those who drink deep well water is the lowest. (4) People over 40 years of age with a family history of liver cancer.

II. High-risk groups for esophageal and gastric cancer include sub-healthy individuals. (1) Individuals over 40 years of age with long-term digestive tract diseases, pain, or discomfort. Frequent consumption of mold-contaminated grains, pickled, smoked, roasted, or rotten foods; smoking and excessive alcohol consumption can all cause gastrointestinal diseases and cancer. Helicobacter pylori infection can cause gastritis, gastric ulcers, and gastric cancer. (2) Individuals with a family history of esophageal or gastric cancer. If there is a family history of cancer in each of the second or third generations, there may be a genetic predisposition to cancer. People with close relatives who have esophageal or gastric cancer may have similar living environments and be exposed to similar carcinogenic factors. (3) Patients with residual stomach. The incidence of gastric cancer is higher in patients with residual stomach after surgery than in the general population. (4) Patients with severe esophageal epithelial hyperplasia, chronic atrophic gastritis, gastric ulcers, or gastric polyps found during screening have a higher risk of developing cancer. (5) Individuals with unexplained hematemesis, melena, or positive occult blood tests in gastric juice or feces. Because cancer can also present with these symptoms, we need to be vigilant.

III. High-risk groups for colorectal cancer are sub-healthy individuals. (1) Individuals with a family history of colorectal cancer have a 4 times higher risk of developing colorectal cancer than the average person. (2) Patients with colon cancer have a 3 times higher risk of developing a second colon cancer after surgery than normal individuals. The second colorectal cancer occurs 2 to 30 years after the first treatment. (3) Areas where schistosomiasis is prevalent are also high-incidence areas for colorectal cancer. It is generally believed that long-term deposition of schistosomiasis eggs on the colonic mucosa leads to adenomatous hyperplasia, which then develops into cancer. (4) Familial adenomatous polyposis. This is an autosomal dominant genetic disease, and 40% to 50% of its offspring may develop the disease. Generally, adenomatous polyposis begins to develop at 8 to 10 years of age, and if left untreated, it will develop into cancer around the age of 40. (5) Chronic ulcerative colitis (Crohn's disease) is closely related to colorectal cancer. The chance of developing colorectal cancer is 6.9 times higher than that of normal individuals, and it often begins 10 years after the onset of chronic ulcerative colitis. (6) The incidence of colorectal cancer is 4 times higher in people who have received pelvic radiotherapy than in those who have not received radiotherapy. Most cases occur 10 to 20 years after radiotherapy, with the cancerous lesions located at the original radiation site. (7) People who eat a high-fat, low-fiber diet for a long time. (8) People with polyps or ulcers in the colon.

IV. High-risk groups for rectal cancer include sub-healthy individuals. Rectal cancer is a common malignant tumor of the gastrointestinal tract, with an incidence rate second only to stomach and esophageal cancer, and is the most common type of colorectal cancer (accounting for about 60%). The vast majority of patients are over 40 years old, with about 15% under 30. It is more common in men, with a male-to-female ratio of (2-3):1. Anal canal and rectal cancer is a common malignant tumor of the intestine and one of the most common tumors in my country. In recent years, epidemiological data have confirmed that with the improvement of living standards, the incidence of this disease is on the rise. In Western countries, the annual incidence rate is 35-50/100,000. For example, in the United States, colorectal cancer ranks first among cancers and second in cancer mortality. Although the incidence rate of this disease in my country is lower than in Western countries, it has been on the rise in recent years. In Shanghai, the incidence rate of colorectal cancer was 6.66/100,000 in 1963, ranking sixth after stomach cancer, uterine cancer, and liver, lung, and esophageal cancer. By 1979, it had reached 20.37/100,000, second only to stomach, lung, and liver cancer. It is evident that anal and rectal cancer has become a major disease threatening people's health. Therefore, it is essential to raise awareness of this disease, ensure early diagnosis and treatment, and improve cure and survival rates.