Introduction

The presence of ectopic liver tissue is a rare developmental abnormality that has previously been found during autopsy and during laparoscopic procedures in the abdomen [₁,₂,₃,₄,₅,₆,₇,₈,₉,₁₀,₁₁]. It has only been described in case reports.

We present two cases of incidental ectopic liver tissue on the gallbladder during elective laparoscopic cholecystectomy. A further review of the world literature of case reports was then performed.

Case Report 1

A 39-year-old lady presented to hospital with a one-month history of right upper quadrant pain. The pain was typical of biliary colic and was associated with vomiting. Past medical history included mild lupus, chronic back pain and depression. She was clinically obese.

Examination revealed right upper quadrant tenderness. Blood tests revealed normal liver function, renal function, a normal white cell count and a haemoglobin level of 11.3 g/dL. She was admitted and an ultrasound scan demonstrated several gallstones in the gallbladder and a normal common bile duct. Although her symptoms settled with conservative management she continued to have epigastric pain. She underwent a gastroscopy, which demonstrated oesophagitis and she was treated with proton pump inhibitors.

She was discharged and later underwent an elective laparoscopic cholecystectomy which was completely uneventful. However, at time of surgery she was found to have an ectopic liver tissue on the gallbladder attached to the liver by a pedicle (Figure 1). Histology demonstrated normal hepatic tissue. She made an uneventful postoperative recovery and remains symptom-free since discharge.

Figure 1

Figure 1

Case Report 2

A 42-year-old gentleman attended the A & E department in April 2006 with right upper quadrant pain consistent with biliary colic. He had no previous medical history but was clinically obese (BMI 42).

Blood tests demonstrated marked liver function derangement (Bilirubin 70 mmol/L(~4 mg/dl), ALP 244 U/L, ALT 497 U/L, Gamma GT 270 U/L). He was admitted and a subsequent ultrasound scan demonstrated: an echogenic focus in the lumen of the gallbladder suggestive of small calculi with a normal common bile duct and fatty infiltration of the liver. He was managed conservatively and was subsequently discharged.

He underwent an elective laparoscopic cholecystectomy in August 2006 and was found to have a small ectopic liver on the gallbladder which was discrete from the liver (Figure 2). Histology demonstrated normal hepatic tissue. He had an uneventful recovery and was discharged with no further issues.

Figure 2

Figure 2

Discussion

As the histological reports of the two specimens showed normal hepatic parenchyma, we feel that the ectopic tissue appeared to be incidental to the underlying pathology of gallstones.

Anatomists have described the presence of ectopic liver lobes in the perinatal liver (11.5% of cases [₁₀]). The persistence of these ectopic tissues markedly drops in the adult (>0.5% based on autopsy [₁₁]). They can be found on the gallbladder, hepatic ligament, thorax and the retroperitoneum [₆]. They can be attached to the liver (and hence an accessory lobe) or a discrete island of hepatic tissue [₁₀].

The ectopic liver tissue is subject to environmental changes and cirrhosis of ectopic tissue has been noted [₁₃]. There have been case reports of primary hepatocellular carcinoma in ectopic tissues (with a tumour-free liver)[₁₃,₁₄,₁₅]. There has been some suggestion that ectopic liver tissue is more prone to cirrhotic and neoplastic changes [₁₃].

Ectopic liver tissue has been reported to have had a compression effect in two case studies: on the pylorus [₁₆] and on the portal vein [₁₇].

Summary

Ectopic liver tissue is a rare developmental abnormality that is often an incidental finding on laparoscopic procedures.

Acknowledgements

Correspondence to

Amar Malhas BSc MB BS MRCS SHO in Surgery 1. Queen Elizabeth Hospital NHS, 2. 2 Scarsdale Villas Stadium road, Kensington, Woolwich, London, London, England England W8 6PR E18 4QH Email: amarmalhas@hotmail.com