Patient selection: proximal biliary stricture
Exclusions: primary sclerosing cholangitis, metastatic perihilar cholangiocarcinoma, extrinsic hilar obstruction by a peripheral tumor, history of previous malignancy, post-cholecystectomy stricture, common bile duct stone, intrahepatic or distal biliary stricture, intraductal papillary neoplasm
Findings associated with a benign proximal biliary stricture:
(1) abdominal pain (odds ratio 3.4)
(2) serum CA19.9 < 100 U/mL (odds ratio 10.4)
(3) absence of a mass on imaging studies (odds ratio 4.7)
Some causes of benign stricture:
(1) post-inflammatory stricture
(2) gallstone disease
(3) IgG4-related cholangiopathy
(4) parasitic infection
