"Blind" evaluation of endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of pancreatic carcinoma: the "double duct" and other signs.

A "blind" review of 40 "look-alike" ERCP examinations was conducted to determine if pancreatic carcinoma could be diagnosed by ERCP findings alone, and if there were specific findings which occurred only in carcinoma. All 11 cases of carcinoma involving the pancreas were diagnosed correctly, with no false positives or negatives. Irregular (nodular or rat-tailed) pancreatic duct encasement or obstruction occurred exclusively in carcinoma. When the adjacent common bile duct was similarly involved (Double Duct Sign), the diagnostic certainty increased. The results suggest that ERCP is an accurate and reliable method for diagnosing pancreatic carcinoma.