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Congenital solitary intrahepatic biliary cyst in infant: A rare case report
J Ped Surg Case Reports 30 (2018) 64e67
Contents lists available at ScienceDirect
Journal of Pediatric Surgery CASE REPORTS journal homepage: www.jpscasereports.com
Congenital solitary intrahepatic biliary cyst in infant: A rare case report Anil Kumar Yadav a, *, Jianghua Zhan b, Shujian Zhang b, Nita Yadav a a b
The Graduate School of Tianjin Medical University, 300070, Tianjin, China Department of Pediatric Surgery, Tianjin Children’s Hospital, Tianjin, 300134, China
a r t i c l e i n f o
a b s t r a c t
Article history: Received 30 August 2017 Received in revised form 6 September 2017 Accepted 17 September 2017
Solitary liver cysts (SLCs) are usually asymptomatic, uncommon and nonparasitic cysts of congenital origin, most frequently discovered during imaging studies. It may develop in the form of simple cyst and biliary cyst. The majority of the cysts that are discovered incidentally remain small. The etiology of SLC is unknown. Perioperative cholangiography is helpful to confirm the connection between cyst and biliary tree. In several clinical situations, including resection of malignant or benign biliary lesions, reconstruction of the biliary system using the Roux-en-Y jejunum limb should be performed as the standard procedure. Ó 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords: Congenital cyst Intrahepatic biliary cyst Intraoperative cholangiography
1. Introduction Solitary liver cysts (SLCs) rarely manifest in infancy. They are unilocular, benign lesions of the liver and can be defined as a simple cyst or a biliary cyst according to the composition of the cyst fluid and the cyst’s anatomical relationship with the biliary tree [1]. SLCs are usually asymptomatic [1]. Perioperative cholangiography should be performed in all cases to detect connections between the SLC and the biliary tree [5]. Management options include percutaneous aspiration, injection of sclerosing agents, laparoscopic or open fenestration, and surgical cystectomy or Roux-en-Y hepaticojejunostomy [2,5]. The aim of this study was to describe the clinical, imaging features, differential diagnosis, histopathological findings and the surgical options for cyst. 2. Case report This full term male infant was antenatally diagnosed with cystic abdominal mass at 28 weeks of gestation. Prenatal diagnosis could not confirm the exact origin of cyst. The diagnostic options could be
* Corresponding author. Tel.:þ86 13752093515; fax: þ86 22 23525331. E-mail addresses: [email protected] (A.K. Yadav), [email protected] (J. Zhan).
mesenteric cyst, duplication cyst, choledochal cyst and omental cyst. Postnatal abdominal ultrasound demonstrated cystic mass but the baby was asymptomatic. At 12 months of age, he was admitted to our hospital for further evaluation. In laboratory findings, total bilirubin 4.8micromol/l, direct bilirubin 2.4micromol/l, ALT 12U/L. PT, alkaline phosphate and albumin were within normal range (Table 1a). Routine urine examination, renal function test and chest x-ray were normal. A repeat abdominal ultrasound showed a 5.9 4.7 5.0 cm homogeneous anechoic hepatic hilum cystic mass. The computed tomography (CT) revealed the cystic mass in the right hepatic lobe, and the size is 5.4 4.8 cm, extending to the hepatic hilar region (Fig. 1a). Magnetic resonance imaging (MRI) showed an irregular single mass in the right hepatic lobe, which is about 5.1 4.6 4.3 cm, adjacent intrahepatic duct was slightly pressed, the mass extending to the hepatic hilar region and has close relationship with intrahepatic bile duct (Fig. 1b). Magnetic resonance(MR) scan was performed to further define the anatomy but it failed to confirm the connection between cyst and biliary tree. As the diagnostic dilemma continued, laparotomy was done. In the meantime echocardiography demonstrated the PDA, which was ligated and the Patient was readmitted after 8 months. We performed a right subcostal incision, which revealed a large cystic mass in the center of the right lobe of liver. The cyst wall was opened which were filled with fluid. Intraoperative cholangiography was done which confirmed the connection between the cyst and biliary
2213-5766/Ó 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). https://doi.org/10.1016/j.epsc.2017.09.017
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67 Table 1a Liver function tests before operation. Normal range
Results
Tests
0e40 60e320 8e40 5.1e18.8 1.7e6.8 3.4e10.3 130e280 35e55
12 U/L 167 U/L 36.4 U/L 4.80 mMOL/L 2.40 mMOL/L 2.40 mMOL/L 287 U/L 43.60 g/l
ALT ALP AST TBil DBil IBil LDH Albumin
tree and biliary strictures (Fig. 1c). The cyst was located close to and has connections with the intrahepatic biliary ducts. Because of biliary strictures, cyst was completely excised and a Roux-en-Y hepaticojejunostomy was performed with enteric drainage (Fig. 2a) and liver biopsy was taken. Perioperative diagnosis was a solitary intrahepatic biliary cyst. Postoperative period was uneventful. He was discharged on 14th post-operative day. Followed up 3 monthly for 1 year, with abdominal ultrasound and liver function test (Table 1b). Histopa-
65
thology showed the wall is composed of fibrous tissue, hemorrhagic cystic wall, focal necrosis, infiltration of inflammatory cells, few areas lined with simple cuboidal epithelium (Fig. 2b).
3. Discussion Congenital non parasitic liver cysts are categorized as solitary or multiple; the latter is associated with polycystic kidney disease and Caroli’s disease. Solitary liver cyst (SLC) never involves other organ [1,3], and is further classified as simple solitary liver cyst and solitary intrahepatic biliary cyst (SIBC). The etiology of SLC is unknown. However it has been hypothesized that obstruction of aberrant bile ducts from infection or as a result of a vascular disruption during the fetal period can be a cause [1,3,4]. But these etiologies does not hold true in our case. SLC is located to and connections with the intrahepatic bile ducts. It is likely that solitary liver cyst is of biliary duct origin. SLCs are usually asymptomatic and their symptoms do not manifest until patients are in their forties or fifties [1]. The anteroinferior segment of the right hepatic lobe is the most frequent site of SLC [1,4].
Fig. 1. a: CT scan (arrow) shows cystic mass in the right hepatic lobe, the mass boundary is irregular, the size is about 54.1 * 48.6 mm, extending to the hepatic hilar region. Fig. 1b: MRI showing an irregular mass in the right hepatic lobe, which is about 5.1 4.6 4.3 cm, the border is clear. Adjacent intrahepatic duct is lightly pressed, the mass extending to the hepatic hilar region and has close relationship with intrahepatic bile duct. (A. left hepatic duct, B. right hepatic duct, C.cyst). Fig. 1c. Intraoperative cholangiogram showing the cyst is communicated with intrahepatic bile duct. (A. right hepatic duct, B. left hepatic duct, C. cyst).
66
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67
Fig. 2. a. Roux-en-Y hepaticojejunostomy. b. Histopathology of right lobe of liver showing the wall is composed of fibrous tissue, hemorrhagic cystic wall, focal necrosis, infiltration of inflammatory cells, only few areas (arrow) lined with simple cuboidal epithelium.
An SLC is usually unilocular and lined by cuboidal or columnar epithelium with no connection to the biliary tree [4]. The outer layer of the cyst wall is composed of collagen, muscle fibers, bile ducts, and liver cells, which are separated from the epithelial lining by vascular tissue [3]. The cystic fluid may be clear, brown, or occasionally bilious [3]. The differential diagnosis included a mesenteric cyst, lymphatic malformation, hepatic malignancies, biliary atresia, choledochal cyst, or liver cyst. Accurate diagnosis is made primarily by radiographic studies often requiring histopathological verification. On ultrasonography, a SLC appears as an anechoic unilocular fluid-filled space with a posterior acoustic enhancement [1]. SLC typically cannot be differentiated from cystic malignant tumors on radiological studies; tissue diagnosis is necessary, even in asymptomatic patients [1]. Histological criteria for an SLC include an outer layer of thin dense fibrous tissue, an inner epithelial lining (cuboidal or columnar), and lack of mesenchymal stroma or cellular atypia [7] as in our case. Perioperative cholangiography should be performed in all cases to detect connections between the SLC and the biliary tree [4]. The communication between the cyst and the biliary tree was seen on cholangiography as in our case. The postoperative course may be complicated by infection, cholangitis, and recurrence [4]. Total excision should be attempted for easily accessible SLCs and enucleating may also be chosen for small cysts [3,6]. When total excision is not possible, partial excision has been recommended [4,6]. As much of the cyst wall as possible should be excised, taking care not to damage vital structures [3]. Internal drainage of the cyst via cystoenterostomy or Roux-en-Y hepaticojejunostomy has been recommended when the biliary system drains into the cyst and bile drainage into the enteric circulation cannot be obtained [4]. Biliary
Table 1b Liver function tests during follow up. Normal range
Results
Tests
0e40 60e320 8e40 5.1e18.8 1.7e6.8 3.4e10.3 130e280 35e55
22 U/L 199 U/L 38 U/L 2.80 mMOL/L 1.20 mMOL/L 1.60 mMOL/L 253 U/L 40.90 g/l
ALT ALP AST TBil DBil IBil LDH Albumin
reconstruction is required in several clinical situations, including resection of biliary malignancies, benign biliary strictures, intraoperative injury, and liver transplantation. Bilioenteric anastomosis using the Roux-en-Y jejunum limb is a well-established approach [8]. Reconstruction using the jejunum allows for safe and permissive anastomosis with infrequent postoperative bile leakage even when the anastomoses involve small intrahepatic branches [9] as in our case. 4. Conclusion A congenital solitary liver cyst is rare, and the differential diagnosis includes a broad spectrum of pathologies. The diagnosis may be challenging, and intraoperative cholangiography should be performed to define the anatomic connection between the cyst and the biliary tree. Since accurate diagnosis can only be made by intraoperative cholangiogram and histopathology which differentiate the cyst from malignant lesions. In several clinical situations, including resection of malignant or benign biliary lesions, reconstruction of the biliary system using the Roux-en-Y jejunum limb should be performed as the standard procedure. Declaration of interest None. Funding sources Tianjin Health Bureau key projects 14KG129; National Science Foundation Projects 81570471. References [1] Macken MB, Wright JR, Lau H, et al. Prenatal sonographic detection of congenital hepatic cyst in third trimester after normal second-trimester sonographic examination. J Clin Ultrasound 2000;28(6):307e10. [2] Tucker ON, Smith J, Fenlon HM, McEntee GP. Giant solitary non-parasitic cyst of the liver. Ir J Med Sci 2005;174(2):60e2. [3] Howard ER, Stringer MD, Colombani P. Surgery of the liver, bile ducts and pancreas in children. second ed., vol. 239. London: Arnold; 2002. p. 21. [4] Berg C, Baschat AA, Geipel A, et al. First-trimester diagnosis of fetal hepatic cyst. Ultrasound Obstet Gynecol 2002;19(3):287e9. [5] Pitt HA. Liver cysts: non-parasitic. In: Carter D, Russell RCG, Pitt HA, editors. Hepatobiliary and pancreatic surgery. fifth ed. London: Chapmann and Hall Medical; 1996. p. 93e7. [6] Guzetta PC, Thopmson WR. Non malignant tumors of the liver. In: O’Neil JA, Rowe MI, Grosfeld JL, Fonkalsrud EW, Coran AG, editors. Pediatric surgery. fifth ed. St. Louis: Mosby; 1998. p. 1505e11.
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67 [7] Yeo C, Matthews J, McFadden D, et al. Shackelford’s surgery of the alimentary tract. seventh ed. Philadelphia, PA: Saunders; 2012. p. 1453. [8] Sondenaa K, Kubota K, Sano K, Takayama T, Makuuchi M. Successful reconstruction of segmental or subsegmental bile ducts after resection of hilar bile ducts: short- and long-term results. Hepatogastroenterology 2004;51:1278e81.
67
[9] Hasegawa K, Kokudo N, Imamura H, Sano K, Aoki T, Miki K, et al. Bilioenteric reconstruction for small bile ducts without mucosa-to-mucosa alignment: long-term results. Arch Surg 2004;139:1050e4.
Contents lists available at ScienceDirect
Journal of Pediatric Surgery CASE REPORTS journal homepage: www.jpscasereports.com
Congenital solitary intrahepatic biliary cyst in infant: A rare case report Anil Kumar Yadav a, *, Jianghua Zhan b, Shujian Zhang b, Nita Yadav a a b
The Graduate School of Tianjin Medical University, 300070, Tianjin, China Department of Pediatric Surgery, Tianjin Children’s Hospital, Tianjin, 300134, China
a r t i c l e i n f o
a b s t r a c t
Article history: Received 30 August 2017 Received in revised form 6 September 2017 Accepted 17 September 2017
Solitary liver cysts (SLCs) are usually asymptomatic, uncommon and nonparasitic cysts of congenital origin, most frequently discovered during imaging studies. It may develop in the form of simple cyst and biliary cyst. The majority of the cysts that are discovered incidentally remain small. The etiology of SLC is unknown. Perioperative cholangiography is helpful to confirm the connection between cyst and biliary tree. In several clinical situations, including resection of malignant or benign biliary lesions, reconstruction of the biliary system using the Roux-en-Y jejunum limb should be performed as the standard procedure. Ó 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords: Congenital cyst Intrahepatic biliary cyst Intraoperative cholangiography
1. Introduction Solitary liver cysts (SLCs) rarely manifest in infancy. They are unilocular, benign lesions of the liver and can be defined as a simple cyst or a biliary cyst according to the composition of the cyst fluid and the cyst’s anatomical relationship with the biliary tree [1]. SLCs are usually asymptomatic [1]. Perioperative cholangiography should be performed in all cases to detect connections between the SLC and the biliary tree [5]. Management options include percutaneous aspiration, injection of sclerosing agents, laparoscopic or open fenestration, and surgical cystectomy or Roux-en-Y hepaticojejunostomy [2,5]. The aim of this study was to describe the clinical, imaging features, differential diagnosis, histopathological findings and the surgical options for cyst. 2. Case report This full term male infant was antenatally diagnosed with cystic abdominal mass at 28 weeks of gestation. Prenatal diagnosis could not confirm the exact origin of cyst. The diagnostic options could be
* Corresponding author. Tel.:þ86 13752093515; fax: þ86 22 23525331. E-mail addresses: [email protected] (A.K. Yadav), [email protected] (J. Zhan).
mesenteric cyst, duplication cyst, choledochal cyst and omental cyst. Postnatal abdominal ultrasound demonstrated cystic mass but the baby was asymptomatic. At 12 months of age, he was admitted to our hospital for further evaluation. In laboratory findings, total bilirubin 4.8micromol/l, direct bilirubin 2.4micromol/l, ALT 12U/L. PT, alkaline phosphate and albumin were within normal range (Table 1a). Routine urine examination, renal function test and chest x-ray were normal. A repeat abdominal ultrasound showed a 5.9 4.7 5.0 cm homogeneous anechoic hepatic hilum cystic mass. The computed tomography (CT) revealed the cystic mass in the right hepatic lobe, and the size is 5.4 4.8 cm, extending to the hepatic hilar region (Fig. 1a). Magnetic resonance imaging (MRI) showed an irregular single mass in the right hepatic lobe, which is about 5.1 4.6 4.3 cm, adjacent intrahepatic duct was slightly pressed, the mass extending to the hepatic hilar region and has close relationship with intrahepatic bile duct (Fig. 1b). Magnetic resonance(MR) scan was performed to further define the anatomy but it failed to confirm the connection between cyst and biliary tree. As the diagnostic dilemma continued, laparotomy was done. In the meantime echocardiography demonstrated the PDA, which was ligated and the Patient was readmitted after 8 months. We performed a right subcostal incision, which revealed a large cystic mass in the center of the right lobe of liver. The cyst wall was opened which were filled with fluid. Intraoperative cholangiography was done which confirmed the connection between the cyst and biliary
2213-5766/Ó 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). https://doi.org/10.1016/j.epsc.2017.09.017
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67 Table 1a Liver function tests before operation. Normal range
Results
Tests
0e40 60e320 8e40 5.1e18.8 1.7e6.8 3.4e10.3 130e280 35e55
12 U/L 167 U/L 36.4 U/L 4.80 mMOL/L 2.40 mMOL/L 2.40 mMOL/L 287 U/L 43.60 g/l
ALT ALP AST TBil DBil IBil LDH Albumin
tree and biliary strictures (Fig. 1c). The cyst was located close to and has connections with the intrahepatic biliary ducts. Because of biliary strictures, cyst was completely excised and a Roux-en-Y hepaticojejunostomy was performed with enteric drainage (Fig. 2a) and liver biopsy was taken. Perioperative diagnosis was a solitary intrahepatic biliary cyst. Postoperative period was uneventful. He was discharged on 14th post-operative day. Followed up 3 monthly for 1 year, with abdominal ultrasound and liver function test (Table 1b). Histopa-
65
thology showed the wall is composed of fibrous tissue, hemorrhagic cystic wall, focal necrosis, infiltration of inflammatory cells, few areas lined with simple cuboidal epithelium (Fig. 2b).
3. Discussion Congenital non parasitic liver cysts are categorized as solitary or multiple; the latter is associated with polycystic kidney disease and Caroli’s disease. Solitary liver cyst (SLC) never involves other organ [1,3], and is further classified as simple solitary liver cyst and solitary intrahepatic biliary cyst (SIBC). The etiology of SLC is unknown. However it has been hypothesized that obstruction of aberrant bile ducts from infection or as a result of a vascular disruption during the fetal period can be a cause [1,3,4]. But these etiologies does not hold true in our case. SLC is located to and connections with the intrahepatic bile ducts. It is likely that solitary liver cyst is of biliary duct origin. SLCs are usually asymptomatic and their symptoms do not manifest until patients are in their forties or fifties [1]. The anteroinferior segment of the right hepatic lobe is the most frequent site of SLC [1,4].
Fig. 1. a: CT scan (arrow) shows cystic mass in the right hepatic lobe, the mass boundary is irregular, the size is about 54.1 * 48.6 mm, extending to the hepatic hilar region. Fig. 1b: MRI showing an irregular mass in the right hepatic lobe, which is about 5.1 4.6 4.3 cm, the border is clear. Adjacent intrahepatic duct is lightly pressed, the mass extending to the hepatic hilar region and has close relationship with intrahepatic bile duct. (A. left hepatic duct, B. right hepatic duct, C.cyst). Fig. 1c. Intraoperative cholangiogram showing the cyst is communicated with intrahepatic bile duct. (A. right hepatic duct, B. left hepatic duct, C. cyst).
66
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67
Fig. 2. a. Roux-en-Y hepaticojejunostomy. b. Histopathology of right lobe of liver showing the wall is composed of fibrous tissue, hemorrhagic cystic wall, focal necrosis, infiltration of inflammatory cells, only few areas (arrow) lined with simple cuboidal epithelium.
An SLC is usually unilocular and lined by cuboidal or columnar epithelium with no connection to the biliary tree [4]. The outer layer of the cyst wall is composed of collagen, muscle fibers, bile ducts, and liver cells, which are separated from the epithelial lining by vascular tissue [3]. The cystic fluid may be clear, brown, or occasionally bilious [3]. The differential diagnosis included a mesenteric cyst, lymphatic malformation, hepatic malignancies, biliary atresia, choledochal cyst, or liver cyst. Accurate diagnosis is made primarily by radiographic studies often requiring histopathological verification. On ultrasonography, a SLC appears as an anechoic unilocular fluid-filled space with a posterior acoustic enhancement [1]. SLC typically cannot be differentiated from cystic malignant tumors on radiological studies; tissue diagnosis is necessary, even in asymptomatic patients [1]. Histological criteria for an SLC include an outer layer of thin dense fibrous tissue, an inner epithelial lining (cuboidal or columnar), and lack of mesenchymal stroma or cellular atypia [7] as in our case. Perioperative cholangiography should be performed in all cases to detect connections between the SLC and the biliary tree [4]. The communication between the cyst and the biliary tree was seen on cholangiography as in our case. The postoperative course may be complicated by infection, cholangitis, and recurrence [4]. Total excision should be attempted for easily accessible SLCs and enucleating may also be chosen for small cysts [3,6]. When total excision is not possible, partial excision has been recommended [4,6]. As much of the cyst wall as possible should be excised, taking care not to damage vital structures [3]. Internal drainage of the cyst via cystoenterostomy or Roux-en-Y hepaticojejunostomy has been recommended when the biliary system drains into the cyst and bile drainage into the enteric circulation cannot be obtained [4]. Biliary
Table 1b Liver function tests during follow up. Normal range
Results
Tests
0e40 60e320 8e40 5.1e18.8 1.7e6.8 3.4e10.3 130e280 35e55
22 U/L 199 U/L 38 U/L 2.80 mMOL/L 1.20 mMOL/L 1.60 mMOL/L 253 U/L 40.90 g/l
ALT ALP AST TBil DBil IBil LDH Albumin
reconstruction is required in several clinical situations, including resection of biliary malignancies, benign biliary strictures, intraoperative injury, and liver transplantation. Bilioenteric anastomosis using the Roux-en-Y jejunum limb is a well-established approach [8]. Reconstruction using the jejunum allows for safe and permissive anastomosis with infrequent postoperative bile leakage even when the anastomoses involve small intrahepatic branches [9] as in our case. 4. Conclusion A congenital solitary liver cyst is rare, and the differential diagnosis includes a broad spectrum of pathologies. The diagnosis may be challenging, and intraoperative cholangiography should be performed to define the anatomic connection between the cyst and the biliary tree. Since accurate diagnosis can only be made by intraoperative cholangiogram and histopathology which differentiate the cyst from malignant lesions. In several clinical situations, including resection of malignant or benign biliary lesions, reconstruction of the biliary system using the Roux-en-Y jejunum limb should be performed as the standard procedure. Declaration of interest None. Funding sources Tianjin Health Bureau key projects 14KG129; National Science Foundation Projects 81570471. References [1] Macken MB, Wright JR, Lau H, et al. Prenatal sonographic detection of congenital hepatic cyst in third trimester after normal second-trimester sonographic examination. J Clin Ultrasound 2000;28(6):307e10. [2] Tucker ON, Smith J, Fenlon HM, McEntee GP. Giant solitary non-parasitic cyst of the liver. Ir J Med Sci 2005;174(2):60e2. [3] Howard ER, Stringer MD, Colombani P. Surgery of the liver, bile ducts and pancreas in children. second ed., vol. 239. London: Arnold; 2002. p. 21. [4] Berg C, Baschat AA, Geipel A, et al. First-trimester diagnosis of fetal hepatic cyst. Ultrasound Obstet Gynecol 2002;19(3):287e9. [5] Pitt HA. Liver cysts: non-parasitic. In: Carter D, Russell RCG, Pitt HA, editors. Hepatobiliary and pancreatic surgery. fifth ed. London: Chapmann and Hall Medical; 1996. p. 93e7. [6] Guzetta PC, Thopmson WR. Non malignant tumors of the liver. In: O’Neil JA, Rowe MI, Grosfeld JL, Fonkalsrud EW, Coran AG, editors. Pediatric surgery. fifth ed. St. Louis: Mosby; 1998. p. 1505e11.
A.K. Yadav et al. / J Ped Surg Case Reports 30 (2018) 64e67 [7] Yeo C, Matthews J, McFadden D, et al. Shackelford’s surgery of the alimentary tract. seventh ed. Philadelphia, PA: Saunders; 2012. p. 1453. [8] Sondenaa K, Kubota K, Sano K, Takayama T, Makuuchi M. Successful reconstruction of segmental or subsegmental bile ducts after resection of hilar bile ducts: short- and long-term results. Hepatogastroenterology 2004;51:1278e81.
67
[9] Hasegawa K, Kokudo N, Imamura H, Sano K, Aoki T, Miki K, et al. Bilioenteric reconstruction for small bile ducts without mucosa-to-mucosa alignment: long-term results. Arch Surg 2004;139:1050e4.