Accuracy of simultaneous measurement of serum biomarkers: Carbohydrate antigen 19-9, pancreatic elastase-1, amylase, and lipase for diagnosing pancreatic ductal adenocarcinoma

Pancreatic cancer is difficult to diagnose early since tumor markers have low sensitivity and specificity. We simultaneously measured serum carbohydrate antigen (CA) 19-9, pancreatic elastase-1, lipase, and amylase, and evaluated the accuracy of a single marker or a combination of two, three, or four markers in the diagnosis of pancreatic ductal adenocarcinoma (PDAC). Seventy-six patients with PDAC were included, and 75 patients with non-PDAC diseases were enrolled as the control group. Blood specimens were collected and analyzed for pancreatic elatase-1, CA19-9, amylase and lipase. Sensitivity, specificity, and accuracy for each individual marker and in combination were determined. In PDAC subjects, abnormal CA19-9 was seen most frequently at 80.3%, followed by pancreatic elastase-1 at 57.9%, lipase at 53.9%, and amylase at 51.3%. In non-PDAC subjects, the percentage of abnormal serum pancreatic elastase-1, CA19-9, lipase, and amylase were 50.7%, 41.3%, 40.0%, and 28.0%, respectively. The accuracy rate of amylase and CA19-9 results combined was 64.9% and was higher than the combination of other markers in the intersection set. In the union set, the group of amylase and CA19-9 combined and the group of lipase and CA19-9 combined had the highest accuracy at 66.2%. In the intersection and union set, the area under the curve of CA19-9 was the highest at 0.695. CA19-9 as a single marker is the most accurate in the clinical diagnosis of PDAC. Combination of lipase, amylase, or pancreatic elastase-1 results does not significantly increase the accuracy of PDAC diagnosis.