Role of Endoscopic Ultrasonography in Patients Suspected of Pancreatic Cancer with Negative Helical MDCT Scan

Abstract

Background: In some patients suspected of pancreatic cancer, no mass can be detected by multidetector computed tomography (MDCT) scan as the cause of biliary obstruction. Methods: All patients suspected of pancreatic cancer between January 2007 and 2009 with a negative MDCT were identified from a database. Results: MDCT was performed for suspected pancreatic cancer in 290 patients, and in 258 a pancreatic mass was found. MDCT failed to establish a diagnosis in 32 patients (11%). In 23 patients (74%) with complete endoscopic ultrasonography (EUS), the cause of the obstruction was correctly diagnosed. A mass in the pancreatic head was found in 15 patients; 13 patients had a malignant tumor, and 2 patients a benign cause of obstruction. Further, EUS diagnosed 3 patients with a superficial adenoma of the papilla and 8 patients with a benign cause of the obstruction. In 5 patients EUS could not detect the cause of obstruction but finally a pancreatic malignancy was diagnosed. The positive predictive value of EUS was 86% and the negative predictive value 63%. Accuracy of MDCT and EUS decreased in the presence of pancreatitis or a biliary endoprosthesis. Conclusion: In patients suspected of pancreatic cancer in whom MDCT fails to demonstrate the cause of obstructive jaundice, EUS identifies 74% of the underlying diseases correctly.