Hyperplastic Luschka ducts: a mimic of adenocarcinoma in the gallbladder fossa

Ducts of Luschka are a developmental abnormality found within the gallbladder fossa in up to 10% of cholecystectomy specimens. They are most often encountered by surgeons when injured during laparoscopic or open cholecystectomy, leading to bile leakage and subsequent peritonitis. Histologically, they are typically composed of lobular aggregates of small ductules lined by bland, cuboidal-to-columnar biliary-type epithelium, associated with centrally located, larger ductules surrounded by concentric fibrosis. We have identified 6 cases of florid Luschka duct proliferation in which the ductules demonstrated irregular growth pattern, loss of characteristic concentric fibrosis, and epithelial atypia that strongly suggested the diagnosis of invasive pancreatobiliary adenocarcinoma or metastatic adenocarcinoma involving the gallbladder serosa. Two of the cases were initially diagnosed as invasive adenocarcinoma, whereas the other 4 were sent for consultation to rule out adenocarcinoma. All cases were associated with marked acute and chronic cholecystitis with mucosal ulceration, cholelithiasis, and thickening of the gallbladder wall. The ducts of Luschka were located within the rim of adherent liver in all 6 cases and the gallbladder serosa in 5 cases. Limited follow-up information was available for all patients with no documentation of progressive disease. Awareness and proper recognition of the anatomic location and histologic features are imperative in distinguishing florid ducts of Luschka from both non-neoplastic conditions and most importantly adenocarcinoma.