Pancreaticobiliary ductal union in biliary diseases. An endoscopic retrograde cholangiopancreatographic study.

To assess whether the anatomy of the pancreaticobiliary ductal drainage into the duodenum has any relationship with biliary diseases we analyzed 259 endoscopic retrograde cholangiopancreatograms. These included 102 normal examinations (control group), 95 patients with gallstone disease, and 21 patients with carcinoma of the gallbladder. In the control group, 64 (63%) subjects had a common channel and 38 (37%) had separated openings for the common bile duct and the main pancreatic duct. By contrast, the prevalence rate of a common channel was significantly lower in gallstone disease [28 (30%); p less than 0.001]. No such difference, compared with controls, was observed in patients with carcinoma of the gallbladder. The length of the common channel in the control group (mean +/- SD, 4.7 +/- 2.5 mm) was similar to that in gallstone disease (4.6 +/- 2.6 mm). However, patients with carcinoma of the gallbladder had a significantly longer common channel (8.3 +/- 4 mm; p less than 0.001) compared with the control group. An abnormally long common channel (greater than or equal to 8 mm) was seen more frequently in carcinoma of the gallbladder (8 of 21; 38%) compared with normal subjects (3 of 102; 3%) and patients with gallstones (1 of 95; 1%); the difference was highly significant (p less than 0.001 for each). These observations suggest a close association between the anatomy of the distal ends of the common bile duct and main pancreatic duct and the development of gallstones and carcinoma of the gallbladder.