Prospective evaluation of common hepatic duct histopathology at the time of choledochal cyst excision ranging from children to adults

Purpose To evaluate common hepatic duct just distal to the HE anastomosis (d-CHD) prospectively for mucosal damage, inflammation, fibrosis, dysplasia, carcinoma in situ, malignant transformation, effects of serum amylase, and symptoms at presentation in CC cases ranging from children to adults. Methods Cross-sections of d-CHD obtained at cyst excision 2018–2023 from 65 CC patients; 40 children (< 15 years old), 25 adults (≥ 15) were examined with hematoxylin and eosin, Ki-67, S100P, IMP3, p53, and Masson’s trichrome to determine an inflammation score (IS), fibrosis score (FS), and damaged mucosa rate (DMR; damaged mucosa expressed as a percentage of the internal circumference). Results Mean age at cyst excision (“age”) was 18.2 years (range: 3 months-74 years). Significant inverse correlations were found for age and DMR ( p = 0.002), age and IS ( p = 0.011), and age and Ki-67 ( p = 0.01). FS did not correlate with age ( p = 0.32) despite significantly increased IS in children. Dysplasia was identified in a 4-month-old girl with cystic CC. Serum amylase was elevated in high DMR subjects. Conclusions High DMR, high IS, and evidence of dysplasia in pediatric CC suggest children are at risk for serious sequelae best managed by precise histopathology, protocolized follow-up, and awareness that premalignant histopathology can arise in infancy.