[Serologic diagnosis of digestive tract cancer]

Serologic diagnosis using body fluids is easy to perform and the analysis of abnormal body fluids can play an important role in diagnosis for cancer. Monoclonal antibodies to tumor associated antigen have contributed very much to this important field, CA 19-9 being an excellent example. We have also established novel monoclonal antibody YH 206 which reacted with the antigen in the sera of approximately half of the patients with gastric or pancreatic cancer. Recent advances in diagnosis using gastric and pancreatic juice were also reviewed.