Pancreatic enlargement in obstructive jaundice. Effects of biliary stream diversion in humans.

To verify the influence of obstructive jaundice on pancreatic growth, the anteroposterior width of the pancreas was measured by computed tomography in 30 cholangiocarcinoma patients excluded patients with distal bile duct tumor (jaundice group) and 74 control subjects. Follow-up examinations were performed on 12 patients with and without internal biliary drainage to elucidate the temporal relationship between pancreatic enlargement and the diversion of the obstructed biliary stream. Histologic analysis on autopsy samples from 13 control and 10 jaundice cases also was performed. Mean pancreatic head and body widths in the jaundice group were 2.93 +/- 0.3 cm and 2.01 +/- 0.3 cm, respectively. These values were significantly greater than those of the controls (2.13 +/- 0.3 cm and 1.49 +/- 0.3 cm, P < 0.01). The glandular widths returned to their normal sizes following internal biliary drainage. No changes were seen in patients who underwent external drainage alone. Histologic examination revealed that enlargement of the acinar cells or of the islet of Langerhans was often seen in the jaundiced patients. Therefore obstructive jaundice is thought to cause pancreatic growth through a trophic effect by interrupting biliary circulation.