Measurement of sialylated stage-specific embryonic antigen-1 in pure pancreatic juice for the diagnosis of pancreatic cancer

Abstract

The diagnostic significance of measuring sialylated stage-specific embryonic antigen-1 (SLX) in pure pancreatic juice was evaluated in 20 patients with pancreatic cancer, 43 with chronic pancreatitis, 13 with cholecystolithiasis, and 15 control individuals. Four fractions of pure pancreatic juice were collected sequentially from the pancreatic duct by endoscopic cannulation. The SLX levels in all four fractions of pure pancreatic juice were significantly higher in patients with pancreatic cancer than in controls. On the other hand, patients with chronic pancreatitis or cholecystolithiasis did not have SLX levels that significantly differed from those of controls in any fraction. When the cut-off value was set as the mean concentration +2 times the standard deviation of the control values, the positive rates of SLX in the first fraction (washout phase) and the third fraction (secretory phase) of pure pancreatic juice from pancreatic cancer were 55% (11/20) and 40% (8/20), respectively. Although the false positive rates in the first fraction were high in chronic pancreatitis (30%) and cholecystolithiasis (31%), such high SLX levels in the third fraction were found only in one (2%) patient with chronic pancreatitis and in one (8%) with cholecystolithiasis. The specificities of the test for pancreatic cancer in the first fraction and the third fraction were 70% (39/56) and 96% (54/56), respectively. These results indicate that the measurement of SLX in the third fraction of pure pancreatic juice is useful as a specific marker for pancreatic cancer.