With the progress of medicine and the improvement of people’s health awareness, it is recommended to do annual physical examination, which includes the examination of tumor markers, the tumor indicators that people often talk about. The common questions about tumor markers from patients in my clinic include these: 1) What do these indicators indicate? (1) AFP: a marker for primary liver cancer, testicular cancer, ovarian cancer, etc.; (2) CEA: a marker for colon cancer, gastric cancer, etc., as well as lung cancer and breast cancer; (3) CA199: a marker for pancreatic cancer, liver cancer, gastric cancer, esophageal cancer, bile duct cancer, etc. (4) glycoantigen CA125: a marker of ovarian cancer, endometrial cancer, fallopian tube cancer, pancreatic cancer is also elevated. (5) Glycoantigen CA153: can be used for the diagnosis of breast cancer patients; (6) Glycoantigen 242 (CA242): a marker of digestive system tumors; (7) Glycoantigen 724 (CA724): a marker of gastric cancer, ovarian cancer and other tumors; (8) Prostate-specific antigen PSA: a specific marker of prostate cancer. (9) CYFRA21-1 (Cy211): a marker for non-small cell lung cancer and other tumors; (10) neuron-specific enolase (NSE): a marker for small cell lung cancer, neuroendocrine tumors and other tumors; (11) human chorionic gonadotropin (HCG): a marker for embryonic cell carcinoma, trophoblastic tumors (choriocarcinoma, staphyloma) and other tumors; (12) (12) Ferritin (SF): a marker for tumors of digestive system, liver cancer, breast cancer, lung cancer, etc.; (13) Thyroglobulin (TG): a marker for thyroid cancer; (14) Squamous cell antigen (SCC): a marker for cervical cancer, squamous lung cancer, esophageal cancer, etc. 2.Does elevated tumor marker mean cancer? It should be emphasized that after a period of clinical observation that people with elevated tumor markers are diagnosed as cancer patients after a comprehensive examination, some of the medical examiners with mildly elevated tumor markers are diagnosed as cancer patients; some of them are diagnosed as cancer after a period of time or even several years; and some of the people with mildly elevated tumor markers return to normal after several months or years. But people with elevated certain tumor markers cannot relax their vigilance and still need regular review. 3.How is the normal range of tumor markers determined? In fact, the normal range of tumor markers does not include the measured values of all normal people, but only the measured values of 95% of normal people, that is to say, 5% of normal people may have the measured value of a certain index outside the normal range. What should be done after finding abnormal tumor markers? (1) Don’t be alarmed and don’t overburden your mind; (2) Have a review. (It is important to say several times.) Some people have only one elevation, and after several times of rechecking, it is normal. This is often caused by non-cancerous factors, and sometimes it is caused by the problem of testing method. If no obvious abnormality is found after comprehensive examination, tumor markers should be rechecked every 2 to 3 months and the decision of when to repeat each test should be made based on the results of tumor marker tests. Various tumor markers can only be used as one of the auxiliary diagnostic indicators. Before a definite diagnosis is made, one should never assume that he or she has cancer because of a mildly elevated indicator, but should be alert and do further examination and observation. There are two major misconceptions to avoid. One of the misconceptions is that an abnormal tumor marker is considered to have malignant tumor. The second misconception is that a normal tumor marker is considered as no malignant tumor. The clinical significance of dynamic testing is much greater. For diagnosed tumors after treatment, if the elevation of tumor markers often indicates the recurrence of tumor or unsatisfactory treatment effect, it can prompt the doctor to adjust the treatment plan.