Ectopic Pancreas Presenting as a Large Gastric Antral Papilla

Table of Contents

Ectopic pancreatic tissue localized in the distal stomach rarely presents symptoms unless it is complicated by bleeding or mucosal ulceration. The appearance on endoscopic ultrasound (EUS) examination is characterized by an indistinct margin, a heterogeneous appearance, and location within either the third or the fourth echo layer [1]. Thickening of the fourth echo layer (muscular hypertrophy) has commonly been seen.

A 67-year-old woman was admitted in order to undergo polypectomy of a gastric lesion (Figure [1 a]). There was no history of abdominal pain, dyspepsia, or signs of bleeding or ulceration. Serum pancreatic enzyme levels were normal.

Work-up, which included upper gastrointestinal endoscopic and EUS examination, revealed a lesion exhibiting a characteristic central umbilication and intramural mass on the front wall of the antrum with a diameter of 20 mm [2] (Figure [1 b]). The lesion looked like a papilla, but it was impossible to insert a catheter. No single endosonographic criterion could be obtained that would enable accurate differentiation between benign and malignant submucosal tumors of the upper gastrointestinal tract [3].

Figure 1 a Gastroscopic view of the papilla-like lesion in the antrum. b Endoscopic ultrasound (EUS) examination demonstrated a heterogeneous appearance and location within either the third or the fourth echo layer.

Most patients with ectopic pancreas are asymptomatic, but nonspecific gastrointestinal symptoms associated with pancreatitis, cyst formation, jaundice, abscess formation, gastric outlet obstruction, and malignant change have been described [4]. Endoscopic biopsy specimens obtained with a standard forceps are often nondiagnostic because the structures that characterize ectopic pancreas are situated below the mucosa.

The patient underwent endoscopic polypectomy, and histologic examination in the submucosa showed dilated cystic ducts with cubic epithelium, fibrosis, and an island of pancreatic tissue (the investigation was performed by Prof. Dr Loy of the Pathological Institute) (Figure [2]). The lesion did not present with disabling symptoms and we think that surgical excision or endoscopic resection should not be performed if the diagnosis is known [5].

Figure 2 Photomicrograph of the ectopic pancreatic tissue.

References

• 1 Matsushita M, Hajiro K, Okazaki K, Takakuwa H.. Gastric aberrant pancreas: EUS analysis in comparison with the histology.  Gastrointest Endosc. 1999;  49 493-497
• 2 Pouessel G, Michaud L, Pierre M H. et al. . Endoscopic diagnosis of a gastric heterotopic pancreas and esophageal atresia: an incidental association?.  Arch Pediatr. 2001;  8 181-185
• 3 Rösch T, Lorenz R, Dancygier H. et al. . Endosonographic diagnosis of submucosal upper gastrointestinal tract tumors.  Scand J Gastroenterol. 1992;  27 1-8
• 4 Sloots C E, de Brauw L M, Bot F J, Greve J W.. False-positive cytology in diagnostic laparoscopy due to ectopic pancreas.  Dig Surg. 1999;  16 434-436
• 5 De Friend D J, Saa-Gandi F W, Humphrey C S, Foster D N.. Symptomatic pancreatic heterotopia treated by local excision.  Gut. 1991;  32 332-333