A high cancer screening index does not prove that one must have cancer. Cancer screening indicators, such as carcinoembryonic antigen CA199, CA125, etc., can only suggest that they may indicate digestive tract tumors or ovarian cancer. However, whether it is a tumor of digestive tract, such as gastric cancer, intestinal cancer or ovarian cancer, etc., must be combined with pathological examination. Pathological examination is the gold standard to confirm cancer diagnosis. Therefore, for mild elevation of cancer screening index found in physical examination, corresponding examinations, such as CT scan plus enhancement of upper abdomen and CT scan plus enhancement of whole abdomen, must be done in time to find out whether there is any occupying lesion in the corresponding area, and then gastroscopy, colonoscopy or puncture examination will be done for the occupying lesion. If cancer cells can be found, the diagnosis of cancer can be confirmed. If no cancer cells are found in pathological examination, cancer can be ruled out.