Predictive value of cyst size for clinical symptoms in patients with prenatally diagnosed choledochal cysts.

Background: Choledochal cysts (CDCs) are common congenital biliary malformations in children. However, current research on whether cyst size links to postnatal clinical symptoms in prenatally diagnosed CDCs remains scarce and unclear. This study aimed to explore the predictive value of cyst size for the occurrence of clinical symptoms in patients with prenatally diagnosed CDCs. Methods: A retrospective review of medical records was conducted for patients with prenatally diagnosed CDCs who were admitted to Fujian Children's Hospital between January 2018 and May 2025. The patients were divided into a symptomatic group (n=15) and an asymptomatic group (n=29) based on the presence or absence of clinical symptoms at the time of surgery. Univariate analyses were performed to screen factors closely related to clinical symptoms. Additionally, we focused on the role of cyst size (i.e., width and length) in predicting the development of CDCs related symptoms. Results: A total of 44 patients were included in the study, with 15 patients in the symptomatic group and 29 patients in the asymptomatic group. The results of univariate analysis showed that patients with clinical symptoms had earlier time of prenatal diagnosis (P=0.02), higher proportion of Todani type IV (P=0.04), higher values of γ-gamma-glutamyl transpeptidase (γ-GGT) and direct bilirubin (DBIL) (both P<0.01). Both cyst length {57 [42, 77] Conclusions: Rapid cyst growth trend is suggestive of an increased risk of clinical symptoms. A cyst length >44 mm and width >36 mm indicates the possible onset of clinical symptoms. Dynamic assessment protocol integrating rapid cyst growth trend with quantified size cut-offs offers a reliable strategy for predicting CDCs-related clinical symptoms.