Rare entity: Ectopic liver tissue in the wall of the gallbladder - A case report

Ectopic Hepatocellular Carcinoma in the Gallbladder Wall With Choledocholithiasis: A Case Report

An ectopic hepatocellular carcinoma (HCC) that originates from the ectopic liver is defined as a hepatic organ or tissue not conventionally linked to surrounding tissues. Ectopic HCC has a rare clinical incidence, and diagnosing it before surgery is challenging. Its characteristics and biological behavior have not been fully elucidated. This report presents a unique case of ectopic HCC in the gallbladder, discontinuous with the liver. A 74-year-old man was referred to our hospital after primarily complaining of fever and right hypochondrium pain. Plain computed tomography revealed a significantly thickened gallbladder wall containing fluid collection and incarceration of gallstone in the common bile duct. He was diagnosed with acute cholecystitis and obstructive cholangitis due to choledocholithiasis. After percutaneous transhepatic gallbladder drainage and endoscopic lithotomy for choledocholithiasis, a cholecystectomy was performed. Macroscopically, the resected gallbladder had a yellowish tumor (1 cm) within the significantly thickened gallbladder wall. Histopathological examination identified moderately differentiated HCC on the ectopic liver, discontinuous with the liver. Immunohistologically, the tumor was finally diagnosed as ectopic HCC with alpha-fetoprotein positive expression.

Case Report: Ectopic Liver (Choristoma) Discovered During Laparoscopic Cholecystectomy

Patient: Male, 47-year-old

Final Diagnosis: Ectopic liver

Symptoms: Right upper quadrant pain

Medication:—

Clinical Procedure: —

Specialty: Surgery

Ectopic liver tissue (choristoma) on the gallbladder: A comprehensive literature review

BACKGROUND

Liver tissue situated outside the liver with a hepatic connection is usually called an accessory liver, and that without a connection to the mother liver, is called ectopic liver tissue.

AIM

To identify studies in the literature on ectopic liver tissue located on the gallbladder surface or mesentery.

METHODS

We present two patients and review published articles on ectopic liver tissue located on the gallbladder surface accessed via PubMed, MEDLINE, Google Scholar, and Google databases. Keywords used included accessory liver lobe, aberrant liver tissue, ectopic liver tissue, ectopic liver nodule, heterotopic liver tissue, hepatic choristoma, heterotopic liver tissue on the gallbladder, and ectopic liver tissue on the gallbladder. The search included articles published before June 2020 with no language restriction. Letters to the editor, case reports, review articles, original articles, and meeting presentations were included in the search. Articles or abstracts containing adequate information on age, sex, history of liver disease, preliminary diagnosis, radiologic tools, lesion size, surgical indication, surgical procedure, and histopathological features of ectopic liver tissue were included in the study.

RESULTS

A total of 72 articles involving 91 cases of ectopic liver tissue located on the gallbladder surface or mesentery were analyzed. Of these 91 patients, 62 were female and 25 were male (no gender available for 4 patients), and the age range was 5 d to 91 years. Forty-nine patients underwent surgery for chronic cholecystitis or cholelithiasis, and 14 patients underwent surgery for acute cholecystitis. The remaining 28 patients underwent laparotomy for other reasons. Cholecystectomy was laparoscopic in 69 patients and open in 11 patients. The remaining 19 patients underwent various other surgical procedures such as autopsy, liver transplantation, living donor hepatectomy, Whipple procedure, and liver segment V resection. Histopathologically, hepatocellular carcinoma was detected in the ectopic liver tissue of one patient.

CONCLUSION

Ectopic liver tissue is a rare developmental anomaly which is usually detected incidentally. Although most studies suggest that ectopic liver located outside the gallbladder has a high risk of hepatocellular carcinoma, this is not reflected in statistical analysis.

Ectopic Liver Tissue in the Gall Bladder: A Rare Entity

Ectopic liver tissue (ELT) is a rare clinical entity that any surgeon faces in their career. Due to the association or propensity to develop hepatocellular carcinoma, this disease has gained clinical importance, and surgeons ought to be aware of the possible intervention and complications that can be associated with it. Incidence has been reported to be 0.24%-0.47%, with the gall bladder being the most common site. Anatomically, ELT in the gall bladder derives its blood supply either from the vascular pedicle arising with or without its own vein from the liver parenchyma or from branches of the cystic artery and, sometimes, through vascular structures embedded within the mesentery lying adjacent to the liver parenchyma. Surgically, it becomes important to delineate the blood supply because, often, the operating surgeon might encounter uncontrollable bleeding if the blood supply has been derived from the liver parenchyma itself. Complications that can be associated with ectopic liver are torsion, bleeding into the peritoneum, cirrhosis, and, sometimes, lead to malignant degeneration to hepatocellular carcinoma. It can be due to metabolic inactivity owing to less efficient vascular and biliary ductal systems, which sometimes might be confused for occult metastases from a primary hepatoma. Gall bladder-associated ELT is best managed by en bloc resection via laparoscopic cholecystectomy, which suffices if the biopsy comes out to be negative. However, as the risk of malignant degeneration still exists in about 3% of cases, some patients might need to undergo a second surgery for a negative resection margin and regional lymphadenectomy.

Misdiagnosed epigastric mass: Ectopic liver

We discuss an ectopic liver misdiagnosed as an abdominal mass and the importance of magnetic resonance imaging (MRI) in liver positional anomalies. A solid midline mass midline adjacent to the liver was found in a 45-year-old female at an external center during an ultrasound investigation conducted for occasional abdominal pain of many years. The patient was referred to us for MRI. MRI revealed a solid epigastric lesion adjacent to the liver but unrelated to the liver parenchyma. The mass was of similar intensity as the liver in all sequences and in postcontrast dynamic phases following hepatospecific contrast material administration. We also observed contrast material excretion into the solid lesion from the biliary ducts in the hepatobiliary phase. The lesion was diagnosed as ectopic liver tissue with these findings.

LEVEL OF EVIDENCE

5 J. Magn. Reson. Imaging 2017;45:761-763.

A rare condition: Ectopic liver tissue with its unique blood supply encountered during laparoscopic cholecystectomy

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Developmental abnormalities of liver including ectopic liver are rare conditions.

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Although it does not usually produce any symptom clinically, it can rarely result in serious complications such as bleeding, pyloric and portal vein obstruction.

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Ectopic liver has the capacity of malignant transformation to hepatocellular carcinoma that makes it essential to be removed.

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The vascular anatomy of ectopic liver should be identified before the dissection of gallbladder in order to prevent hemorrhage from the liver parenchyma.

Introduction

Developmental abnormalities of liver including ectopic liver tissue (ELT) are rare conditions. Few cases presenting ELT have been reported in literature till now. Even though the most common area seen is gallbladder, it is detected both abdominal and thoracic sites. There is a relationship between HCC and ectopic liver that necessitates the removal.

Presentation of case

A 51-year-old female was hospitalized because of abdominal pain. Gallstone and bile duct dilatation were determined during ultrasonographic (USG) evaluation. The patient was operated for cholecystectomy following a successful endoscopic retrograde cholangiopancreatography (ERCP). During operation, a mass located on gallbladder with its unique vascular support was identified and resected together with gallbladder. The mass had a separate vascular stalk arising from liver parenchyma substance and it was clipped with laparoscopic staples. The histopathological examination revealed that the mass adherent to gallbladder was ectopic liver confirming the intraoperative observation. The postoperative course of patient was uneventfull and she was discharged at the second day after the operation.

Discussion

Ectopic liver tissue is incidentally found both in abdominal and thoracic cavity. ELT can rarely be diagnosed before surgical procedures or autopsies. It can be overlooked easily by radiological techniques. Although it does not usually produce any symptom clinically, it can rarely result in serious complications such as bleeding, pyloric and portal vein obstruction. ELT also has the capacity of malignant transformation to hepatocellular carcinoma that makes it essential to be removed.

Conclusion

Although ELT is rarely seen, it should be removed when recognized in order to prevent the complications and malignant transformation.