LETTER

JOP. J Pancreas (Online) 2013 Nov 10; 14(6):684-685.

Gastric Ectopic Pancreas: Not Always an Innocent Bystander

Evangelos Kalaitzakis¹, Jacob Elebro³, Jan Johansson²

Departments of ¹Gastroenterology and ²Surgery, Skåne University Hospital; ³Clinical Pathology, University and Regional Laboratories Region Skåne. Lund, Sweden

Dear Sir,

A 38-year-old male patient presented to the emergency room due to acute epigastric pain, nausea and vomiting. Physical examination revealed tenderness in the upper abdomen. Body temperature was 37.3°C. C-reactive protein was 113 mg/L (reference range: 0-3 mg/L) and his white blood cell count was raised (15.5 x10⁹/L; reference range: 3.5-8.8 x10⁹/L). Renal and liver function tests and serum pancreatic amylase were normal. He was otherwise healthy and was not taking any medications. Upper gastrointestinal endoscopy showed a subepithelial lesion in the gastric antrum (Figure 1). Abdominal computed tomography scan revealed a heterogeneous 4 cm malignant-looking lesion in the gastric antrum with suspected invasion of the perigastric fat (Figure 2). Endoscopic ultrasound (EUS) confirmed the presence of a subepithelial lesion in the antrum, that had heterogeneous appearance and involved all subepithelial layers of the gastric wall (Figure 3). An EUS-led fine needle aspiration (FNA) showed inflammatory cells only. The patient recovered symptomatically and blood tests normalized within 5 days. However, on the grounds of the imaging findings, malignancy could not be excluded and distal gastrectomy was performed. Histopathology of the surgical specimen confirmed the presence of ectopic pancreas in the gastric antrum (Figure 4a) but showed no cancer. However, there was both chronic and acute inflammation with neutrophil infiltration (Figure 4b). Twelve months following surgery he was asymptomatic.

Figure 1. Upper gastrointestinal endoscopy revealed a subepithelial lesion in the gastric antrum with endoscopic appearance consistent with an ectopic pancreas.

Figure 2. A computed tomography scan showed a heterogeneous 4 cm malignant-looking lesion in the gastric antrum with suspected invasion of the perigastric fat tissue.

Figure 3. EUS showed a heterogeneous lesion involving all layers of the gastric wall (beyond the mucosal layer).

Figure 4. Histopathology of the surgical specimen showed the presence of acini and ductal structures in the proximity of gastric mucosa, i.e. gastric ectopic pancreas (H&E x4) (a.) and acute and chronic inflammation with reactive ductal changes (H&E x60) (b.).

Although gastric ectopic pancreas is usually an incidental finding, occasionally, it may be the cause of symptoms mainly due to acute inflammation in the ectopic tissue [1, 2]. Malignant transformation has also been described [3]. Differential diagnosis includes other types of subepithelial gastric lesions such as gastrointestinal stromal tumors, leiomyomas, lipomas, etc. [4]. Rarely acute inflammation may develop in ectopic pancreas and pseudocyst formation has also been reported [5]. Clinicians should be aware of the rare occurrence of acute inflammation in gastric ectopic pancreas, as improvement on follow-up EUS [2] together with negative cytology on EUS-FNA and patient recovery may obviate the need for surgery.

Received October 15^th, 2013 – Accepted October 16^th, 2013

Keywords Abdominal Pain; Endosonography; Accessory pancreas

Competing interests None to declare

Correspondence
Evangelos Kalaitzakis
Department of Gastroenterology
Skåne University Hospital
221 85 Lund
Sweden
Phone: +46-46.171.000
Fax: +46-46.2110.908
E-mail: evangelos.kalaitzakis@medicine.gu.se; kalvag@hotmail.com

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