Forme Fruste Choledochal Cysts in Children: Clinical Presentation and Treatment Outcomes-A Retrospective Multicenter Study

Abstract

Purpose: Forme fruste choledochal cyst (FFCC) is a choledochal cyst with minimal or no dilatation of the extrahepatic bile duct (EHBD) and is usually associated with an anomalous pancreaticobiliary junction (APBJ). While sharing similar symptoms, inflammation, and malignant potential with classic biliary cysts, FFCC is often overlooked on ultrasound. This paper aims to present the experience of two tertiary pediatric centers in managing FFCC. Methods: In this retrospective study, the clinical data of pediatric patients treated for FFCC at two tertiary pediatric surgical centers between 1 January 2008 and 31 December 2023 were analyzed. The primary outcome was the clinical success of the surgical procedure, defined by the resolution of symptoms and the absence of major complications. Secondary outcomes included postoperative complications, type and duration of surgical procedures, and length of hospital stay. All patients underwent biliary reconstruction via either Roux-en-Y hepatico-jejunostomy or hepatico-duodenostomy. Clinical outcomes, including postoperative complications and patient follow-up, were evaluated. Results: Fourteen children (9 girls, 5 boys; aged 18 months to 12 years) underwent surgical treatment of FFCC. The mean age at surgery was 5.3 ± 3.8 years, and the mean diameter of the common bile duct was 7.9 ± 1.2 mm. Thirteen patients underwent Roux-en-Y hepatico-jejunostomy, and one underwent hepatico-duodenostomy. Over a mean follow-up period of 6.2 ± 3.6 years, no cholangitis or anastomotic stricture cases were observed. Two patients (14.3%) experienced minor wound infections managed conservatively. Conclusions: FFCC remains a diagnostic challenge due to its subtle imaging findings and non-specific clinical presentation. However, once identified, surgical excision with biliary reconstruction, most commonly via Roux-en-Y hepatico-jejunostomy, is a safe and effective treatment with excellent long-term outcomes. Given the potential for serious complications if left untreated, FFCC should be actively considered in pediatric patients with unexplained pancreatitis or biliary symptoms, even in the absence of overt ductal dilatation.

Keywords: choledochal cyst; forme fruste choledochal cyst; fusiform choledochal cyst; pancreaticobiliary malunion; type 1C choledochal cyst.

Figure 1

An abdominal ultrasound of a 2-year-old girl shows a dilated CBD with a diameter of 8.2 mm.

Figure 2

Diagnostic procedure in patient with suspected FFCC: (A)—MRCP in an 8-year-old girl, showing a dilated CBD with a diameter of 6.7 mm and an anomalous pancreaticobiliary junction; (B)—ERCP in a 12-year-old girl, showing a dilated CBD with a diameter of 8 mm and an anomalous pancreaticobiliary junction.

Figure 3

Intraoperative cholangiography in a 21-month-old boy, showing a dilated CBD with a diameter of 9 mm and an anomalous pancreaticobiliary junction.

Figure 4

Correlation between CBD diameter and symptom severity. The Spearman correlation coefficient was ρ = 0.13, with a p-value = 0.66, indicating no statistically significant correlation.

Figure 5

Correlation between age and symptom severity. The Spearman correlation coefficient was ρ = −0.30, with a p-value = 0.29, indicating no statistically significant correlation.

Figure 6

Correlation between CBD diameter and total bilirubin level. A Spearman correlation analysis revealed a moderate positive correlation between CBD diameter and total bilirubin level (ρ = 0.36), which was not statistically significant (p = 0.20).