Value of ultrasonographic examination combined with measurement of serum tumor markers in the diagnosis of pancreatic cancer of less than 3 cm in diameter.

Ultrasonographic examinations and measurements of CA 19-9 and elastase 1 were done simultaneously in 14 patients with resectable pancreatic cancer of less than 3.0 cm in longest diameter and 48 patients with pancreatitis. Although a pancreatic mass was detected ultrasonically in only six (42.9%) of the patients with tumors of less than 3.0 cm in diameter, one or more of the abnormal ultrasonic findings (a pancreatic mass and dilatation of the pancreatic and/or bile duct) was significantly more frequent in patients with pancreatic cancer than in those with pancreatitis. An abnormally high level of CA 19-9 and/or elastase 1 also was significantly more frequent in patients with pancreatic cancer than in those with pancreatitis. The rates of detection of pancreatic cancer by ultrasonography only and by measurement of tumor markers only were 92.9% and 100%, respectively, but the specificities and predictive values of positive results by each of these tests alone were low. Thirteen (92.9%) of 14 pancreatic cancers were found in patients giving positive results by both ultrasonography and measurement of tumor markers, whereas no tumors were found in patients giving negative results in both of these examinations. A combination of these two examinations raised the specificity and predictive value of positive results to 87.5% and 68.4%, respectively, but had little or no influence on the sensitivity or predictive value of negative results. Therefore, patients in whom ultrasonographic findings are abnormal and in whom the serum levels of tumor markers also are abnormally high should be examined more extensively. This combination of examinations indicates the possibility of earlier detection of pancreatic cancer.