Carcinoma of the gallbladder and anomalous arrangement of the pancreaticobiliary ductal system: cell kinetic studies of gallbladder epithelial cells.

Anomalous arrangement of the pancreaticobiliary ductal system (AAPB), a congenital anomaly defined as a union of the pancreatic and biliary ducts located outside the duodenal wall, is a newly designated disease entity, and is frequently found in adult patients with gallbladder carcinoma (GBX). In the present study, the relationship of AAPB and GBX was investigated. We studied 27 patients with GBX and AAPB, 34 patients with AAPB and without GBX, and as a control group, 56 patients without AAPB (10 with GBX, 24 with cholecystolithiasis, and 22 with normal gallbladder). Tissue sections from cancerous and non-cancerous mucosa of the gallbladder of all of these patients were stained for proliferating cell nuclear antigen (PCNA), Ki-67 nuclear antigen, and bromodeoxyuridine (BrdU). The Ki-67 labeling index (Ki-67-LI), PCNA labeling index (PCNA-LI), and BrdU labeling index (BrdU-LI) of the noncancerous mucosa in the patients with AAPB and/or GBX were significantly higher than those in the patients without GBX and AAPB (P < 0.01). These indices of the noncancerous mucosa in the patients with AAPB and GBX were significantly higher than those in the patients with either AAPB or GBX (P < 0.05). Cell proliferation in the gallbladder epithelia was accelerated in patients with AAPB. Consequently, AAPB appears to be an important risk factor for the occurrence of GBX.