ca724 is a non-specific tumor marker, that is to say, even if the index of ca724 is elevated, it does not necessarily mean that there is a malignant tumor, but it is of guiding significance for tumor screening. ca724 is mainly used in the auxiliary diagnosis of gastric cancer, ovarian cancer, non-small cell lung cancer and breast cancer, as well as monitoring the treatment effect and recurrence of malignant tumors. Tumor screening is an important way for early detection of cancer and pre-cancerous lesions, and the common methods for tumor screening include blood test indicators, Pap smear in gynecological physical examination, ultrasound, X-ray, tumor marker screening, anorectal fingerprinting, and molybdenum-palladium mammography, etc. Among them, tumor marker screening belongs to the group of screening tests. Among them, tumor marker screening is a broad-spectrum tool, which needs to be carried out in accordance with the patient’s specific conditions and symptoms, and has a certain degree of probability. Tumor markers such as CEA, CA72-4, CA19-9 and CAl25 are commonly used for screening. It is recommended that if the patient himself contains chronic gastritis and other cancer-related diseases, work to be exposed to carcinogens and other conditions, it is best to do regular tumor screening, can be detected early, early treatment, to avoid the emergence of the condition is difficult to cure the situation.