Dilation of Both Pancreatic Duct and the Common Bile Duct on Computed Tomography and Magnetic Resonance Imaging Scans in Patients With or Without Obstructive Jaundice

Abstract

"Double-duct sign" (strictures in both common bile duct [CBD] and pancreatic duct [PD] with proximal dilation) on endoscopic retrograde cholangiopancreatography is considered suggestive of pancreatic malignancy. Dilation of CBD and PD is frequently noted on computed tomography/magnetic resonance imaging scans, sometimes found incidentally in patients without jaundice. The prevalence of malignancy in these patients is not established. In this retrospective analysis, consecutive patients who underwent endoscopic ultrasound (EUS) at a tertiary care hospital from 2002 to 2006 for suspected pancreatic malignancy and had double-duct sign on imaging were included. We evaluated (1) prevalence of malignancy in patients with or without obstructive jaundice and (2) performance characteristics of EUS-fine-needle aspiration (FNA) in diagnosing malignancy in this setting. A final diagnosis of pancreatic malignancy was made in 142 (85.5%) of 166 patients with and 4 (5.9%) of 68 without obstructive jaundice (P < 0.005). The accuracy of EUS-FNA for diagnosing malignancy in patients with or without obstructive jaundice was 92.8% versus 98.5%. Dilation of both PD and CBD on computed tomography/magnetic resonance imaging scans is suggestive of pancreatic malignancy. The prevalence of malignancy, however, is markedly lower in patients without obstructive jaundice but is clinically significant and merits further diagnostic evaluation. Endoscopic ultrasound-FNA is highly accurate for diagnosing malignancy in this setting.