At present, tumor has become the biggest killer threatening human health. With the increasing standard of living and people’s health awareness, more and more healthy people are joining the team of cancer prevention medical checkups. Many patients have a common worry, holding the medical examination report in their hands, they are often anxious because they cannot read some data and indicators in it. For example, when several tumor markers are found to be higher than the reference value, they will panic and subjectively think that they have a tumor. So, what exactly do tumor markers mean? What do they mean for your health? Do elevated tumor markers mean tumor? What are the factors that can affect the screening of tumor markers? If cancer is suspected, what other tests should be done to confirm? First of all, we must understand what exactly are tumor markers? Tumor markers are usually considered to be substances synthesized or released by tumor cells or produced by the body in response to tumor cells during the process of tumor occurrence and proliferation. When tumor occurs in the body, certain tumor markers in blood, cells, tissues or body fluids may increase accordingly. Therefore, tumor markers are mainly used in clinical practice for the detection of primary tumors, screening of tumor high-risk groups, differential diagnosis of benign and malignant tumors, judgment of tumor development degree, observation and evaluation of tumor treatment effect, and prediction of tumor recurrence and prognosis. Then what factors will affect the examination of tumor markers? Firstly, some benign diseases such as chronic liver disease, chronic kidney disease, cholelithiasis, diabetes and taking over some drugs. Secondly, physiological changes and some bad habits, such as pregnancy, smoking, alcoholism, etc. It has also been found that prostate related tumor markers may also increase after rectal examination, so rectal examination should not be performed before blood collection. In addition, contamination during blood sampling, improper preservation of specimens, differences in reagents and lack of standardization of testing may also interfere with the test results. The instruments and reagents used for tumor marker testing in different hospitals vary in principle, and the reference values quoted by each laboratory for each item and their own survey statistics may not be the same, therefore, one cannot freely compare their measured values and draw conclusions about the severity of the disease. Therefore, if we find elevated tumor markers in the physical examination, we should not be too nervous. Generally speaking, the diagnosis of tumor cannot rely on tumor marker examination alone, but only continuous observation of dynamic changes of tumor markers can be used as a basis for judgment. After getting the test report, it is better to consult with oncologists. If a certain tumor marker is elevated in one test result, please treat it rationally and ask the doctor to analyze the test result and exclude some factors that affect the test result (such as smoking, chronic diseases, etc.) before deciding whether it is necessary to test again every 2~4 weeks. If there is only a single mild elevation or no major change in the results of each test, there is no need to be so nervous. However, if the physical examination reveals that one or several tumor markers are persistently elevated, then you should be more alert and need further examination by CT, ultrasound and other methods. In particular, pathological examination is required to make a clear diagnosis (cytopathological examination is the “gold standard” for diagnosing whether a tumor is benign or malignant). Before a clear pathological histological diagnosis is made, one should not be sure that one is suffering from cancer just because one index is mildly elevated, or even take anti-tumor treatment to avoid unnecessary harm and loss, but should be vigilant and take further examination and observation.