Choledochal cysts are rare congenital cystic dilatations of the biliary tree. Surgical
resection is felt to reduce the risk of malignant degeneration, which can be seen
in 40 % – 60 % by the fifth decade [1]
[2]. Proposed mechanisms for malignancy include reflux of pancreatic juices in the setting
of an anomalous pancreaticobiliary junction (APBJ) causing chronic inflammation or
bile stasis, leading to “carcinogenic” bile acid generation [3]. We present a patient with choledochal cysts where serial cholangioscopy demonstrated
visual and pathologic evidence of the metaplasia to dysplasia sequence.
The patient was a 47-year-old woman who had previously undergone cholecystectomy and
presented with ongoing right upper quadrant pain and a dilated common bile duct on
imaging, along with mild elevations in alkaline phosphatase and transaminases. Endoscopic
retrograde cholangiopancreatography (ERCP) revealed retained stones and a cystically
dilated distal bile duct suspicious for a type III choledochal cyst (choledochocele).
The cyst and long common channel were consistent with APBJ and biopsies revealed intestinal
metaplasia. The patient opted to undergo annual surveillance with alternating magnetic
resonance cholangiopancreatography (MRCP) and cholangioscopy.
The index video cholangioscopy (Olympus XCHF-B140Y, Tokyo, Japan) showed intestinal
mucosa within the cyst and pathology showed intestinal metaplasia. Repeat video cholangioscopy
2 years later (Olympus TJF-Y008 /CHF 280K003) revealed “tumor vessels” and probe-based
confocal endomicroscopy (Cellvizio, Mauna Kea, Paris, France) demonstrated three malignant
Miami criteria, including thick dark bands, dark clumps, and epithelial structures
concerning for malignancy [4] ([Video 1]). Biopsies demonstrated atypia but, because of the advanced imaging findings, the
patient was referred for pancreaticoduodenectomy. The resected specimen revealed low
grade dysplasia ([Fig. 1]).
Video 1 Video cholangioscopy and confocal endomicroscopy of a choledochal cyst in a patient
undergoing annual surveillance.
Fig. 1 Histopathological images (hematoxylin and eosin [H&E] stained) showing: a a representative section of the choledochal cyst in the resected specimen (magnification × 200)
with villiform mucosa lined by epithelium with a predominantly intestinal phenotype
and globular mucin droplets within many of the epithelial cells that are diagnostic
of intestinal metaplasia; b a focus of low grade dysplasia arising from a background of intestinal metaplasia
within the choledochal cyst in the resected specimen (magnification × 400), which
is characterized by the loss of globular mucin droplets within the epithelium, in
conjunction with hyperchromatic, elongated, pseudostratified epithelial cell nuclei.
Source: Dr. Jeffrey Kaplan, University of Colorado.
This case depicts the progression of a choledochal cyst from intestinal metaplasia
to dysplasia documented by video cholangioscopy and provides further support for the
aforementioned sequence of carcinogenesis in choledochal cysts. We also demonstrate
suspected dysplasia by video cholangioscopy and confocal endomicroscopy that aided
the decision-making process to proceed with surgery, despite non-confirmatory sampling
for neoplasia.
Endoscopy_UCTN_Code_TTT_1AR_2AK
Endoscopy E-Videos is a free access online section, reporting on interesting cases and new techniques
in gastroenterological endoscopy. All papers include a high
quality video and all contributions are
freely accessible online.
This section has its own submission
website at
https://mc.manuscriptcentral.com/e-videos
