The increasing incidence of cancer has caused widespread concern. In recent years, many hospitals have introduced “tumor marker” medical checkups, but many people are unable to make appropriate judgments when they get the test results and face the half-understood letters and data on the medical checkup report. The “symbolic meaning” of tumor markers In tumor diagnosis, although pathological diagnosis is the “gold standard” for tumor diagnosis, tumor marker test is easy to perform and less harmful to human body, only blood or body fluid is needed to detect early cancer. However, because tumor marker tests are easy to perform and less harmful to human body, they can detect early signs of cancer with only blood or body fluids. Tumor markers are chemical substances that reflect the presence of tumors. They are either not found in normal adult tissues but only in embryonic tissues, or their levels in tumor tissues greatly exceed those in normal tissues. Their presence or quantitative changes can suggest the nature of tumors, and lend to the understanding of tumor histogenesis, cell differentiation, and cell function to help in tumor diagnosis, classification, prognosis judgment, and treatment guidance. What exactly does their presence mean? “Alpha-fetoprotein (AFP)”, a very common tumor marker, has a normal concentration of <20ug/L in normal adult serum, and can detect more than 80% of liver cancers and most reproductive system tumors, such as ovarian cancer. The normal concentration of AFP in normal adult serum is 10-30ug/L. When the concentration of AFP is >400ug/L for more than 1 month or >200ug/L for more than 2 months, the presence of primary liver cancer is highly suspected. It should be noted that some benign diseases can also cause elevated AFP, for example, 10% of hepatitis patients have elevated AFP levels <50ug/L, 30% of cirrhosis patients have elevated AFP levels <500 ug/L, and pregnancy can also cause significant elevated AFP, but usually <400 ug/L. "Elevated CEA indicates the presence of pancreatic cancer, colon cancer and other gastrointestinal tumors, with a positive rate of 88%-91% in pancreatic cancer, 76% in lung cancer, and 73% in colon, breast and ovarian cancer. CEA in combination with another tumor marker CA242 is currently considered to be the best indicator for monitoring colon cancer and is more sensitive than X-ray and proctoscopy in the treatment of colorectal cancer. In terms of predicting patient prognosis, patients with normal preoperative CEA have a high surgical cure rate and are less likely to recur after surgery; if preoperative CEA is already elevated, it indicates the presence of peripheral invasion and metastasis and a poor prognosis. CEA is also elevated to varying degrees in patients with smoking, ulcerative colitis, pancreatitis, and colonic polyps. The normal value of "glycosyl antigen CA19-9" is <37ku/L. It is a gastrointestinal tumor-associated antigen and is a common indicator for the diagnosis and differentiation of pancreatic cancer, with a seropositivity rate of 93% in patients with pancreatic cancer and an increase in patients with hepatocellular carcinoma, gastric carcinoma, carcinoma of the jugular and bile duct. CA12-5 is also elevated in acute pancreatitis, cholestatic cholangitis, bile duct stones and liver diseases, but rarely exceeds 120ku/L. The normal value of "glycosyl antigen CA125" is < 35ku/L. It is significantly elevated in pancreatic cancer and other gastrointestinal tumors, endometrial cancer and fallopian tube cancer. CA12-5 is particularly valuable in the differentiation of benign and malignant ovarian masses, with a sensitivity of 78%, specificity of 95%, positive predictive value of 82% and negative predictive value of 91%. mild elevation of CA125 is still seen in some benign diseases, such as the first 3 months of pregnancy, during menstruation, endometriosis, uterine fibroid degeneration, uterine fibroids, benign ovarian tumors, acute pancreatitis, pericardial infections, etc. " The normal value of "glycosyl antigen CA153" is < 25ku/L. It can be used for the diagnosis of breast cancer patients, especially for the early diagnosis of metastatic breast cancer. 23% of primary breast cancer and 69% of metastatic breast cancer have elevated serum CA15-3, and only 10-20% of stage I and II breast cancer patients (early stage) have elevated serum CA15-3. CA15-3 is elevated in only 10-20% of patients with stage I and II breast cancer (early stage), so it is not used for the early diagnosis of breast cancer. For advanced stage patients, if CA15-3 is >100ku/L, metastasis is definitely present. In addition, CA15-3 is elevated in 80% of pancreatic cancer, 71% of lung cancer, and 63% of rectal cancer. 5.5% of normal 16% of benign breast patients also have elevated CA15-3. “Prostate specific antigen PSA is a specific marker for prostate cancer. The normal value is <2.6ug/L. The overall positive rate is as high as 82%-97% for intraperitoneal carcinoma with 70% sensitivity and 100% for metastatic carcinoma. However, it is worth noting that these tumor markers do not correspond to the tumor one by one. Therefore, people with normal indicators should not ignore the symptoms of the disease and seek medical consultation in time, while the latter should relax and have regular review. How to read the medical examination report? The physical examination report mainly compares the tumor marker detection value with the normal reference value. If there is a very obvious increase, the cancer suspicion is very high and further comprehensive examination should be done, and if necessary, PET-CT whole body scan is needed. Even if the level is slightly exceeded, it should not be ignored. In order to completely exclude the possibility of early stage cancer, you need to go to the hospital for rechecking every one or two months. If it continues to be elevated, one should suspect that cancer is developing. If there is no significant elevation all the time, it is usually a benign lesion, which may be an organ inflammation. If a cancer patient finds that the marker is significantly higher after surgery than before surgery, the possibility of recurrence should be considered and a doctor should be promptly asked to interpret and do further examination to determine whether it is a recurrence. Who should be screened for cancer prevention? All people with high risk of cancer should have cancer screening. If you are an adult over 45 years old and have one of the three major cancer-causing factors, you should have a cancer prevention screening once a year. One of the three major cancer-causing factors is the family genetic factor of cancer. For example, people whose mothers or sisters have had breast cancer in their family have a higher risk of breast cancer than those who have no family history. The second is the medical history factor: 80% of liver cancer patients have a history of hepatitis B. Long-term people belong to the high-risk group of stomach cancer. The third is occupational factor: if you are often exposed to radioactive substances or toxic substances in your work, or if your work environment is heavily polluted, you are more likely to develop cancer. In addition, people with long-term bad habits, such as smoking and drinking hot water, sleeping late, holding stool, loving to be serious and eating less fruits and vegetables, also belong to the high-risk group of cancer.