Abstract
A blind study of 49 patients with narrowing of the common bile duct or pancreatic duct on endoscopic retrograde cholangiopancreatography (ERCP) was done. The double duct sign appeared in 4 of 8 pancreatic carcinoma patients, but also occurred in 15 of 41 pancreatitis patients. Other signs, which occurred only in carcinoma in prior studies (nodular, eccentric narrowing, and eccentric and irregular rat-tailed stenosis) also occurred in both groups. Morphological ductal changes are not reliable as the only ERCP criteria in differentiating pancreatic carcinoma from pancreatitis. The most reliable criterion for pancreatitis was multiple stenoses in 1 duct. Pancreatic carcinoma cannot be diagnosed accurately if signs of pancreatitis are also present, and other examinations may be needed.