Choledochal cyst of the proximal cystic duct: a taxonomical and therapeutic conundrum

Abstract

Isolated choledochal cysts involving the cystic duct are rare. We present a case of a choledochal cyst involving only the proximal cystic duct, and discuss the taxonomic and therapeutic challenges. There is a need for a clearly defined classification system for these cysts as they may be categorised as either type II or type VI cysts. The optimal treatment remains debatable, with some authors recommending a bilioenteric reconstruction owing to the wide cystic duct-bile duct junction. However, we suggest that a cholecystectomy should be performed with examination of the specimen and frozen section in case of any abnormality rather than upfront bile duct excision. In addition, given the rarity of this condition and the paucity of long-term data, we recommend meticulous follow-up for development of any malignancy.

A new variant of Choledochal cyst-type VI: a rare case presentation and review of the literature

“…Choledochal cysts is a rare type of biliary malformation, and cystic duct cysts that do not involve other biliary systems are even rarer [ 8 , 9 ]. Clinical symptoms of cystic duct cysts are usually similar to other types of Choledochal cysts.…”

Case Report: Isolated Cystic Dilatation of the Cystic Duct: A Misdiagnosed Case Preoperatively

“…A choledochal cyst is a rare biliary malformation with an incidence of 1 in 30,000 to 1 in 50,000 in European countries with a relatively higher incidence of 1 in 1,000 in Asian countries (2,5). The choledochal cyst is classified into five main types by Todani according to shape and location (6).…”

“…The first is a cholecystectomy including the CDC that is precisely enough oncologically, which is recommended if the drainage to the bile duct is through a narrow neck and the extrahepatic bile duct is not cystic. The second is a cholecystectomy with excision of the extrahepatic bile duct combined with an end-to-side and hepaticojejunostomy, which is recommended for cases with a wide drainage neck or a choledochal cyst coexisting with the CDC (3,5,10,11).…”

“…Because the appearance of the cyst diverticulum is similar to that of a congenital choledochal cyst, only a few cases were misdiagnosed as type II choledochal cyst preoperatively ( 1 , 2 ). There are two hypotheses about the etiology of CDC: one, in embryonic development, one side of the cystic duct wall is a congenital weakness due to the uneven development of the cystic duct wall for the lack of ganglion cells ( 7 ); two, an abnormal pancreatic-bile duct junction (APBDJ), which accounts for about 13 (2/15)−42% (21/50) of choledochal cyst cases ( 5 , 8 ). In the present case, the caudal portion of the cystic duct was found behind the head of the pancreas and converged into the common bile duct at an acute angle and low insertion.…”

Laparoscopic excision of a Type II choledochal cyst with cystolithiasis

“…Often, CDCs present with biliary dyskinesia, stones, pancreatitis, hepatic abscess and cholangitis. [ 4 5 ] Ultrasound shows a characteristic cystic or fusiform dilatation of the common hepatic duct or the intrahepatic duct, distinct from the gall bladder. [ 6 ] MRCP is the diagnostic method of choice for biliary ductal pathologies and is a safe, non-invasive pre-operative investigation.…”