Incidental Finding of Ectopic Liver during Laparoscopic Cholecystectomy

Backround

Congenital liver anomalies are rare [1], however, ectopic liver tissue (ELT) is starting to be a significant topic as more cases are reported. The incidence of ELT is not well studied, but some reports show that it ranges between 0.27% and 0.47% [1]. Moreover, Ahmet et al. in a study of 932 patients showed that the prevalence was around 0.1% and the real incidence was not estimated accurately due to the lack of awareness to this anomaly [2]. In front of this asymptomatic entity, most – if not all – diagnoses are done post-operatively [1] or on autopsy, whereas some reports showed that it can be diagnosed preoperatively if a high index of suspicion is involved [3,4]. On the other hand, when symptoms occur, they manifest as abdominal right upper quadrant pain due to torsion, hemorrhage, and necrosis or rupture [1]. Moreover, ectopic liver has been reported in different body organs. For instance, gallbladder is the most common location of ELT [1–5]. Other locations reported include the lower peritoneal cavity [6], stomach [5,7], spleen [8,9], umbilical ligament [9], and thorax [10]. Here we describe 2 cases of ectopic liver on the gallbladder, encountered during laparoscopic cholecystectomy.

Case Reports

CASE 1:

Case 1 was a 44-year-old Lebanese female presented with a 3-month history of recurrent right upper quadrant pain. Workup showed multiple microlithiasis by ultrasound, which did not detect any other abnormal finding. As a result, the patient was scheduled for laparoscopic cholecystectomy. During the procedure a maroon colored, about 1-cm mass was detected incidentally. It was attached only to the fundus of the gall-bladder and had a similar consistency to the liver (Figure 1A). Cholecystectomy with resection of the mass was done and the patient was discharged home after an uneventful 1-day hospital stay. Histological evaluation showed this mass to be an ectopic liver parenchyma with preserved structure and normal hepatocytes without biliary tract and without any sign of dysplasia or malignancy (Figure 1B).

CASE 2:

Case 2 was a 62-year-old Lebanese female who presented for recurrent abdominal right upper quadrant pain. Workup was done and was significant for multiple gall stones with no signs of acute cholecystitis with normal liver function tests. The patient was scheduled for a laparoscopic cholecystectomy. During the operation an incidental maroon colored, about 0.5-cm mass was detected attached to the gallbladder (Figure 2A).

Cholecystectomy was done with resection of the mass for histological examination, and the patient was discharged home on the second day with no complications. The pathology report showed the mass to be ectopic liver parenchyma with developed portal system, however, no biliary tract was identified (Figure 2B).

Discussion

STUDY LIMITATIONS:

Correlation studies are needed to elicit a significant approach towards such an entity. Our study included two case reports that aimed to draw attention to ELT pathology, which has malignant potential.

Conclusions

ELT may be encountered on the gallbladder during laparoscopic cholecystectomy. If such tissue is encountered, it is recommended to excise it and send it for histopathological examination to exclude malignant transformation. On the other hand, one should widen the differential diagnosis of intra-peritoneal or intra-thoracic masses on imaging studies that are widely used such as computed tomography scans and ultrasounds.