Carcinoembryonic antigen 9000+ng/ml is not necessarily cancer. Normally, the normal value of carcinoembryonic antigen is between 0~5ng/ml, and the test result of 9000+ng/ml indicates that there is an abnormal situation in the body, which may be caused by many kinds of cancers, such as colorectal cancer, gastric cancer, or lung cancer, but it is not necessarily cancer, and it may also be related to many factors, such as colon polyps, ulcerative colitis and intestinal obstruction, and so on. Patients with carcinoembryonic antigen of more than 9000 ng/ml should undergo further examination in time to clarify the reasons for the abnormal elevation of this value. Patients should also be careful not to eat greasy food or drink a lot of alcohol before the test to prevent the test results from being affected.