The CEA index of bowel cancer may not necessarily increase. CEA, also known as carcinoembryonic antigen, is one of the indicators of digestive tumor of patients. Of course, if the tumor is more advanced, such as lymph node metastasis or retroperitoneal multiple lymph node metastasis, distant metastasis, etc., CEA index will increase, and AFP and CA199 index will also increase. If patients have digestive system symptoms, it is recommended to do colonoscopy or abdominal CT examination.