[SC6 antigen for the diagnosis of pancreatic cancer before operation].

SC6 antigen, defined by monoclonal antibody SC6 purified by our laboratory, was measured with a sandwich immunoradiometric assay. Its normal upper limit was considered 41 U/ml. Levels of serum SC6 antigen, a new tumor marker for pancreatic cancer, were assayed in 42 patients who were diagnosed as having pancreatic cancer before operation, acute pancreatitis in 16, and chronic pancreatitis in 7, involving 40 healthy controls. The concentration of SC6 antigen of 19 from the 42 patients was higher than normal upper limit. 15 of the 19 patients was last diagnosed as having pancreatic cancer by operation and pathology. The sensitivity, specificity and predictive value of this assay for pancreatic cancer was 76.2% (15/21), 94% and 75%. The levels of SC6 antigen in 4 patients with pancreatic cancer were observed in different times. The false positive rate of serum SC6 antigen was lower than that of CA19-9. The results show that the antigen is significant for diagnosis, prognosis and observation of the change of serum SC6 antigen for pancreatic cancer. It may be of help to find early pancreatic cancer.