Clinical implications of pediatric biliary intraepithelial neoplasia diagnosed from a choledochal cyst specimen

Abstract

Biliary intraepithelial neoplasia (BilIN), a noninvasive precursor of cholangiocarcinoma, can undergo malignant transformation. Cholangiocarcinoma progression is often attributed to chronic inflammation affecting the bile ducts and gallbladder. Choledochal cysts are precursors to cholangiocarcinoma. BilIN has rarely been documented in children; therefore, we explored the clinical significance of pediatric BilIN. We retrospectively analyzed the records of 15 patients histopathologically confirmed to have BilIN after undergoing surgery for choledochal cysts. Age, sex, admission symptoms, age at surgery, biliopancreatic duct junction abnormality presence/absence, complete resection, postoperative complications, and disease course were investigated. Five males and ten females were included. Specimen analysis revealed BilIN-1, BilIN-2, and BilIN-3 in four, six, and five patients, respectively. All patients survived and underwent outpatient follow-up. All liver function tests were within the normal range during the observation period. Ultrasounds were normal in seven patients. Two patients each had pneumobilia and partial dilatation of the intrahepatic bile ducts. No suspicious findings for cholangiocarcinoma have yet been confirmed. The potential progression of choledochal cysts to BilIN in children was demonstrated. These results underscore the importance of early and thorough excision of choledochal cysts, including resection margins for associated lesions, particularly in children with predisposing risk factors for biliary tract inflammation.