P1361 - A Unique Case of Pyloric Gastric Adenoma: Endoscopic Detection, Echoendosonographic Characterization, and Removal

Anabel Liyen Cartelle, MD¹, Erik Holzwanger, MD¹, Samuel Igbinedion, MD², Sultan Mahmood, MD¹, Harry Rosenberg, MD¹, Tyler Berzin, MD, FACG¹, Mandeep Sawhney, MD, MS¹, Moamen Gabr, MD, MSc,¹, Douglas Pleskow, MD, FACG^3
1Beth Israel Deaconess Medical Center, Boston, MA; ²Center for Advanced Endoscopy, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA; ³BIDMC, Boston, MA

Introduction: Pyloric gland adenomas (PGA) are rare precancerous epithelial polyps that exhibit gastric pyloric gland differentiation. Correct diagnosis is important given high malignant potential. We present a unique case of a female patient with gastroesophageal reflux disease (GERD) found to have a suspected subepithelial lesion (SEL), characterized by echoendosonography (EUS), with histopathologic identification as a PGA.

Case Description/Methods: A 62-year-old woman with a past medical history of rheumatoid arthritis, anemia, and GERD presented as a referral for EUS after she was found to have a 10 mm subepithelial nodule within a hiatal hernia on a previous EGD. She had an unremarkable physical exam, vital signs, and laboratory studies. Her upper endoscopy revealed a small hiatal hernia and distal grade A esophagitis. In the stomach, diffuse erythema was compatible with gastropathy. A single sessile 10mm polyp was detected within the hiatal hernia sac. EUS was then performed which revealed a thickened mucosal layer in the distal esophagus, however no discrete lesions. The polyp was removed via a single piece hot snare polypectomy. Histologically, glandular proliferation of back-to-back mucinous glands was present, consistent with a pyloric gland adenoma with no signs of dysplasia. She was advised to return in 6 months for surveillance endoscopy.

Discussion: We present the case of a PGA found within a hiatal hernia sac. These neoplasms are challenging to diagnose, and surveillance has not been standardized due to their rarity. PGAs account for 2-2.7% of all gastric adenomas, with reported advancement to adenocarcinoma in 12-47% of cases. Grossly, PGAs can appear as polypoid lesions, although some can be irregular mucosal, flat, ulcerative, or even submucosal tumor-like. Histologically, they are characterized by back-to-back pyloric glands that are well-demarcated from the surrounding mucosa. Wide acceptance of PGAs as an entity in North America was delayed until 2009 with the publication of the second largest case series in the literature at the time by Chen et al. from Johns Hopkins. This case series corroborated previously noted female predominance, location in the gastric body, and association with autoimmune gastritis. As with our case, EUS can assist in evaluation and locoregional staging of these lesions. Increased recognition by endoscopists is paramount and further endoscopic surveillance guidelines are needed to minimize future malignant transformation.



Disclosures:


Anabel Liyen Cartelle, MD¹, Erik Holzwanger, MD¹, Samuel Igbinedion, MD², Sultan Mahmood, MD¹, Harry Rosenberg, MD¹, Tyler Berzin, MD, FACG¹, Mandeep Sawhney, MD, MS¹, Moamen Gabr, MD, MSc,¹, Douglas Pleskow, MD, FACG³. P1361 - A Unique Case of Pyloric Gastric Adenoma: Endoscopic Detection, Echoendosonographic Characterization, and Removal, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.