Intragastric Ectopic Liver.

BACKGROUND

Ectopic liver (EL) is a rare developmental anomaly defined as hepatic tissue located outside the native liver without vascular or biliary continuity. It is most commonly reported in the gallbladder but has also been described in other intra-abdominal and extra-abdominal sites. The gastric location is exceptionally rare, with only a handful of cases reported in the literature.

CASE PRESENTATION: We present the case of a 49-year-old previously healthy male with a 2-month history of dyspepsia and heartburn who underwent diagnostic gastroscopy. This latter showed a 15 mm antral submucosal lesion with central umbilication. Endoscopic ultrasound (EUS) of the lesion showed a well-defined, hypoechoic, heterogeneous 14.2 × 8 × 10.4 mm mass involving the mucosa, muscularis mucosa, and submucosa. EUS-guided fine needle biopsy using a 22 G needle yielded adequate tissue. Histopathological examination demonstrated normal hepatocyte plates with one-cell thickness, highlighted by reticulin staining. Special stains, including Perl's iron, periodic acid Schiff (PAS), and PAS with diastase, showed no abnormal inclusions or hemosiderin deposits, and no pancreatic or ductal structures were identified. These findings were diagnostic of ectopic liver tissue. The lesion showed no evidence of malignancy.

DISCUSSION: EL is usually detected incidentally during surgery or autopsy, and preoperative diagnosis is challenging due to its small size, asymptomatic course, and unfamiliarity among clinicians. Gastric EL is exceedingly rare, with only 3 cases previously described in the pylorus or fundus. Our case is unique as it represents the first reported antral location and was diagnosed preoperatively with EUS-guided biopsy.

CONCLUSION

Although rare, EL should be considered in the differential diagnosis of gastric submucosal lesions. Histological confirmation is essential to exclude malignant transformation.

LEARNING POINTS: Ectopic liver tissue in the stomach is very rare and should be looked for during histopathological examination.When identifying a well circumscribed submucosal mass within the gastrointestinal tract, ectopic liver tissue should also be taken into account in the differential diagnosis.Microscopic examination should be carried out to rule out pathological changes since development of hepatocellular carcinoma is possible.