Endoscopic submucosal dissection as alternative to surgery for complicated gastric heterotopic pancreas

Abstract

Background: Gastric heterotopic pancreas (GHP) is generally asymptomatic and rarely features complications such as pancreatitis, pseudocysts, gastric outlet obstruction, bleeding, obstructive jaundice, or intussusception. However, the treatment of complicated GHP is challenging and often requires surgical resection.

Aim: To investigate the clinical outcomes of endoscopic submucosal dissection (ESD) as alternative to surgical resection for complicated GHP.

Methods: This is a single-center, retrospective study. Between January 2013 and December 2017, a total of 5 patients underwent ESD for complicated GHP at Asan Medical Center. Patients who were diagnosed with complicated GHP were treated conservatively as with general practice for acute pancreatitis. After conservative management for resolving the acute phase of pancreatitis, ESD was performed as definitive treatment for complicated GHP. ESD was performed using the conventional method under conscious sedation. The clinical features of patients and tumors, procedure-related characteristics, and long-term outcomes were investigated.

Results: The age of the 5 patients ranged from 28-43 years. Two of the patients were males. All lesions were located in the greater curvature of the antrum. On endoscopic ultrasonography during the pain episode, all lesions were located across the muscularis mucosa, submucosa, and proper muscle layers. The median lesion size was 20 [interquartile range (IQR), 18-35] during the pain episode at the time of the diagnosis of complicated GHP, and 15 mm (IQR, 9-33) at the time of ESD after conservative treatment. The procedure time ranged from 15-120 min. There were no procedure-related adverse events such as perforation or bleeding. The length of hospital stay after the procedure ranged from 2-4 d. All patients were symptom free during the median follow-up period of 46.0 mo (IQR, 39-60).

Conclusion: ESD appears to be a feasible and effective treatment option for complicated GHP based on the favorable clinical outcomes.

Keywords: Endoscopic submucosal dissection; Gastric; Heterotopic pancreas; Pancreatitis.

Figure 1

Endoscopic submucosal dissection of complicated gastric heterotopic pancreas (patient 5). A: Endoscopic ultrasonography image showing a homogeneous hypoechoic lesion with cystic (hypoechoic) foci that was located within the 2^nd, 3^rd, and 4^th layers; B: A 1.5 cm subepithelial tumor with umbilication was observed on the greater curvature of the antrum; C: The lesion borders were marked; D: Saline with epinephrine was submucosally injected, and a circumferential mucosal incision was made; E: The submucosal connective tissue and part of the muscularis propria were dissected; F: The resected specimen was fixed; G: Heterotopic pancreas is located in the submucosa underlying intact gastric mucosa (hematoxylin-eosin; original magnification, × 40); H: Normal pancreatic acini with ducts are noted (× 200).

Figure 2

Computed tomography and endoscopic ultrasonography images of each patient at the time of diagnosis of complicated gastric heterotopic pancreas. A-E: Correspond to patient 1, 2, 3, 4, and 5, respectively. The computed tomography and endoscopic ultrasonography findings of each patient are summarized in Table 1.

Figure 3

The clinical course of lesion size according to abdominal pain are summarized. A: Patient 1; B: Patient 3; C: Patient 4; D: Patient 5.

Figure 4

Representative histologic images of gastric heterotopic pancreas. A: Patient 1: Pancreatic tissue is in proper muscle with involvement of resection margin (arrow) (hematoxylin-eosin; original magnification, × 40); B: Patient 3: There is focal nest of cells and bluish material with fibrosis and severe cautery artifact (× 100); C: Patient 4: Submucosal fibrosis with foreign body reaction and dystrophic calcification (arrow) was noted (× 40); D: Patient 5: Pancreatic tissue is in submucosa overlying gastric mucosa (× 40).