Tumor markers exist not only in tumor tissues but also in normal tissues. Alpha-fetoprotein (AFP), alpha-L-amylosidase (AFU), r-glutamyl transpeptidase (r-GT), carcinoembryonic antigen (CEA), glycoantigens CA199,CA125,CA153,CA50,CA724,CA242 are clinically recognized cancer tumor markers. Through years of clinical research, AFP can be used for primary liver cancer with ninety-five percent accuracy and the highest specificity, but also in combination with imaging. You cannot diagnose cancer with 1 drop of blood. It is not scientific to diagnose cancer with one drop of blood. Pathology is needed to confirm the diagnosis, which is only 99% accurate. Scientifically, there is no 100% accurate diagnosis method.