Carcinoembryonic antigen is only a relatively effective indicator for GI tumor screening, it is an auxiliary and reference indicator, the sensitivity and specificity are not very high, in order to make a clear diagnosis, it is necessary to take a biopsy of the lesion for pathological examination, which is the most effective and accurate way of diagnosis, specific analysis is as follows: 1. Carcinoembryonic antigen is a common clinical tumor marker, usually associated with adenocarcinoma, if carcinoembryonic antigen is elevated, it If the carcinoembryonic antigen is elevated, it suggests the possibility of adenocarcinoma, but if it is only a little bit higher than normal, it needs to be reviewed regularly, don’t worry too much, maybe it is caused by some non-cancerous reasons, but not except that it is caused by adenocarcinoma. If it is exponentially higher, or even tens of times higher than normal, other related examinations must be performed at this time. 2. If there is a mass, pathological examination is required to make a definite diagnosis of malignancy or benign disease in the end. Take the lesion tissue or tissue or cells obtained by puncture, under the microscope according to the changes in cell morphology and structure, and finally give a clear pathological diagnosis.