High carcinoembryonic antigen does not necessarily mean that a patient has cancer. Some of our patients are very anxious and nervous when they have high carcinoembryonic antigen, and they are afraid of cancer, but after examination, no malignant tumor is found; some patients have advanced tumor, but the carcinoembryonic antigen can still be a normal level. Whether the patient really has cancer or not, we need to combine it with other tests, such as ultrasound, imaging and pathology.