Significance of carcinoembryonic antigen levels and cytology of pure pancreatic juice in diagnosis of pancreatic cancer.

The diagnostic accuracies of measurement of carcinoembryonic antigen (CEA) and analysis of the cytologic characters of pure pancreatic juice were assessed in 16 control subjects, 20 patients with pancreatitis and 22 patients with pancreatic cancer. Pure pancreatic juice was collected from the pancreatic duct by endoscopic cannulation using a duodenofiberscope after intravenous administration of secretin. The pancreatic fluid was centrifuged and the supernatant was used for CEA assay, while the cell pellet was examined cytologically. Abnormally high CEA levels in the pure pancreatic juice were significantly more frequent in patients with pancreatic cancer; an increased CEA concentration in the pancreatic juice was found in 68.2% of the patients. The location of the cancer had no influence on the CEA level of the pancreatic juice, but the level tended to be high when the tumor had distant metastases. Positive cytologic findings were obtained in specimens of pure pancreatic juice of 68.2% of the patients with pancreatic cancer. Positive cytologic results were more frequent in patients with carcinoma of the head of the pancreas than in those with carcinoma of the body or tail, and those with localized tumors had the lowest yield of positive cytologic results. For sensitive tests, it was necessary to collect pure pancreatic juice containing no contrast medium. High CEA levels and positive cytological results were significantly more frequent in pancreatic juice obtained 10 to 20 minutes after secretin stimulation than in those collected immediately after stimulation. Correct diagnosis of malignancy was made by CEA assay alone or by cytological examination alone in 68.2% of the patients examined, while a combination of these methods raised the diagnostic rate to 86.4%.