What is the value of carcinoembryonic antigen when colitis and colon polyps are present at the same time cannot be estimated, it may be in the normal range or mildly high, as explained below. 1. Normal range: Carcinoembryonic antigen is generally produced by tumor cells, which is a specific tumor marker. Colitis and colon polyps are not cancers, so they are generally not elevated and are within the normal range, i.e. 0~5ng/mL. 2. Mildly high: Carcinoembryonic antigen may be mildly elevated in some benign lesions, such as colitis and colon polyps. At this time, it is necessary to regularly review and monitor the indicators of carcinoembryonic antigen, and it is of little significance if it stays at the upper limit of the reference value; if it stays elevated, then it may be cancerous. Some colitis and colon polyps have the possibility of cancer, carcinoembryonic antigen has auxiliary value and reference value, need to go to the hospital regularly to review the index, and with colonoscopy, early diagnosis, early treatment.