Early diagnosis is the key to the treatment of tumor. Once malignant tumor develops, patients often deteriorate, especially in late stage, the prognosis is poor, so early diagnosis and early treatment are extremely important. Therefore, people should have sufficient understanding and vigilance to malignant tumors, and must actively seek medical consultation when there are related symptoms. There are many special examinations for tumors, such as X-ray, ultrasound, CT, MRI, endoscopy, biomarker, cytology, histology and molecular biology. These examinations can diagnose tumor from different angles and different aspects, and each of them has its own limitations. The emergence of the concept of tumor markers has played a great role in the early diagnosis of tumors. With the progress of molecular biology and human genome project, more and more specific tumor markers have been discovered and applied, providing a new way for early diagnosis of tumors. For example, CEA, AFP, CA-153, CA-199, CA-125, PSA, NSE and so on. Their clinical significance are: 1. Early tumor screening. The overall screening of all tumor markers has a certain general significance in the screening of tumors. In general, each tumor marker mainly targets one kind of cancer, but each tumor marker exists in every patient at the same time. In our country, after the 70s, in Shanghai and other places, through the AFP screening of a large number of people, many patients with liver cancer, especially small liver cancer, have been detected. The same effect can be achieved in patients with prostate cancer. Therefore, tumor marker screening has great application value for high-risk groups. Therefore, tumor marker screening is of great value to high-risk groups. 2.Differential diagnosis after the appearance of tumor symptoms or suspicious masses. When a patient is suspected to have tumor, the detection of tumor markers is very helpful to identify benign and malignant tumors at this time. 3. Judgment of biological characteristics and disease stage. Once the diagnosis is clear, the basal level of tumor markers should be measured immediately in order to provide help in estimating the prognosis. 4.Efficacy observation and judgment of prognosis. It is the most valuable role of tumor markers. Tumor markers increase before surgery and decrease after surgery, indicating successful surgery; slightly decrease after surgery and then re-elevate, suggesting that the surgery did not work; decrease after surgery and significantly increase after some time, suggesting tumor recurrence or metastasis. This kind of indication often precedes the appearance of clinical symptoms by several months. After treatment, the rise and fall of tumor markers correlate well with patient outcome and prognosis. Tumor markers decrease after treatment indicates that the treatment is effective; if tumor markers continue to increase after treatment, the treatment plan should be replaced. If tumor markers continue to increase after replacing the treatment plan, it often indicates recurrence or metastasis. 5. Combined detection of multiple tumor markers can improve the sensitivity of diagnosis. Tumor is the result of multiple cloning of single mutated cells, and its occurrence is a multi-step and multi-gene cancer process. The biological characteristics of tumor cells are complex and polymorphic, which are manifested in the differences of different tumor pathological types after carcinogenesis, the heterogeneity of tumor cells of the same pathological type, and the differences of tumor cell genotypes, i.e. cell phenotypes. There are cells with different characteristics in a tumor, which may differ in growth rate, surface receptors, immune characteristics, invasiveness, metastasis, and toxicity to drugs. Therefore, the same tumor may contain one or more tumor markers, while different tumors or different tissue types of the same tumor may have both common and different tumor markers. In order to improve the positive rate of tumor marker detection, some tumor markers with higher specificity are selected for combined detection, which can improve the application value of tumor markers. For example: complete set of tumor (male and female).