Background: Mucus glycoproteins are often present in the sera of patients with pancreatic cancer, and their detection and quantification can be used in serologic diagnosis.
Methods: A novel enzyme-linked "sandwich" assay (CAM 17.1/WGA) has been developed in which a lectin, wheat germ agglutinin (WGA), is bound to the solid phase to capture serum glycoproteins, and after addition of test sera, a monoclonal antimucin antibody (CAM 17.1) and peroxidase-tagged second antibody are used as a detection system.
Results: The test has been applied to sera from 79 patients with pancreatic cancer and 120 controls. The CAM 17.1/WGA assay alone had a sensitivity of 78% and specificity of 76% in the diagnosis of pancreatic cancer. Combination of the CAM 17.1/WGA test with a previously described peanut lectin binding assay (PNA/ELLA) provided a sensitivity of 92% and specificity of 70%, whereas combination of the CAM 17.1/WGA assay with the CA 19-9 radioimmunoassay had a sensitivity of 85% and specificity of 76%. Combination of all three tests had a sensitivity of 94% and specificity of 66%. In nonjaundiced patients, the combination of CAM 17.1/WGA and PNA/ELLA had a sensitivity of 93% and specificity of 79% in the diagnosis of pancreatic cancer.
Conclusions: This new test adds significantly to the armamentarium of serologic tests for pancreatic cancer. These tests are particularly effective when used in combination to detect different mucin-borne carbohydrate antigens. They deserve more widespread use, particularly in examining nonjaundiced patients with unexplained abdominal pain or weight loss.