Sixteen patients with carcinoma of the pancreas have been examined by duodenoscopy and varying degrees of retrograde pancreatography. A standardized roentgenographic technique consisting of immediate filming after injection and 20 minute follow-up studies was used to assess contrast medium retention. On the basis of this standardized methodology, failure of the pancreatic duct to drain on a 20 minute delayed film appears to be indicative of carcinoma of the head of the pancreas. Benign noncalculous chronic pancreatitis may have a pancreatographic appearance anatomically similar to carcinoma, but is distinguished by its non-obstructed draining characteristics. All of the patients with delayed ductal drainage had confirmed adenocarcinoma of the head of the pancreas. Two of these lesions were small, resectable carcinomas.