Clinical and pathologic features of proximal biliary strictures masquerading as hilar cholangiocarcinoma

BACKGROUND: Nontraumatic inflammatory hilar strictures are uncommon, but are known to mimic malignancy. This study examines the clinical and pathologic features of benign idiopathic strictures. STUDY DESIGN: Patients without a history of trauma or earlier biliary operation treated for benign strictures were identified. Clinical information was obtained from the medical record and all resected specimens were reexamined. RESULTS: From January 1992 to July 2003, 275 patients with proximal biliary strictures were referred. Among these, 22 patients had a final histologic diagnosis of benign stricture, despite a suspected preoperative diagnosis of malignancy. All 22 patients under-went resection of the extrahepatic biliary tree, which in 10 patients was combined with en bloc partial hepatectomy. Histologic reexamination identified five different benign processes: lymphoplasmacytic sclerosing pancreatitis and cholangitis, primary sclerosing cholangitis, granulomatous disease, nonspecific fibrosis/inflammation, and stone disease. Major postoperative morbidity occurred in 6 (26%) patients but none died. No preoperative clinical or radiographic features were identified that could reliably distinguish patients with benign strictures from those with cancer. CONCLUSIONS: "Malignant masquerade" of the proximal bile duct results from several different underlying conditions, and differentiating benign strictures from cancer remains problematic. The treatment approach should continue to be resection for presumed malignancy.