Is preventive resection of the extrahepatic bile duct necessary in cases of pancreaticobiliary maljunction without dilatation of the bile duct?

Background: No consensus has been reached on whether preventive resection o f the extrahepatic bile duct is necessary in cases of pancreaticobiliary ma ljunction (PBM) without dilatation of the extrahepatic bile duct (undilated type). Methods: Sixty-eight patients with PBM underwent corrective surgery and sev eral clinical characteristics and pathological findings including K-ras poi nt mutation were evaluated. Results: Unlike dilated bile duct, none of the patients with undilated type duct had clinical symptoms in early childhood. In patients with either cys tic or spindle type duct, amylase levels in the bile duct were >10(4) U/I, whereas those in patients with undilated type duct were <10(4) U/I. Postope rative scintigraphy of the biliary system of undilated type revealed no evi dence of cholestasis. After surgery, eight patients with undilated type duc t, in whom the bile duct had been preserved, had no further clinical sympto ms and no evidence of malignancy. Bile duct tissue specimens revealed no hy perplasia, dysplasia or cancerous lesions and they had no K-ras mutation in undilated type. Conclusion: The results showed that there was little bile stasis, injury to the mucosa was mild and less genetic changes could be seen in patients wit h undilated type duct. Therefore, in patients without dilatation of bile du ct and advanced cancer, cholecystectomy alone is sufficient.