Thomas Jefferson University Philadelphia, PA, United States
Award: Presidential Poster Award
Brenna Welman, BA1, Ian Holmes, MD2, Sana Sultan, MBBS3, Jia-Ling Huang, MD2, Anand R. Kumar, MD, MPH2 1Thomas Jefferson University, Philadelphia, PA; 2Thomas Jefferson University Hospital, Philadelphia, PA; 3Crozer Chester Medical Center, Philadelphia, PA
Introduction: Submucosal Tunneling Endoscopic Resection (STER) is a novel approach for removal of subepithelial gastrointestinal tumors. STER can provide important diagnostic information when endoscopic ultrasound (EUS) fails. We report a 43-year-old woman with a complex gastric subepithelial mass who successfully underwent diagnostic removal via STER.
Case Description/Methods: A 43-year-old woman with a history of colonic neuroendocrine carcinoma in her brother underwent an upper endoscopy for dyspepsia that showed a 2 cm gastric antral subepithelial mass. No ulceration, central umbilication, or pillow sign were seen. EUS of the mass showed mixed solid (hypoechoic) and cystic components arising predominantly in the submucosa with a small (< 1 cm) solid (hypoechoic) component within the superficial muscularis propria. Fine needle biopsies (7 passes) were non-diagnostic but suspicious for neuroendocrine tumor (NET).
She was referred to a multidisciplinary team of medical and surgical oncologists and an advanced endoscopist. STER was recommended with the alternative of partial gastrectomy.
STER was successfully performed. After submucosal injection, a 2 cm wide mucosal incision was made 2 cm proximal to the mass with submucosal tunnel until the mass was reached. Careful submucosal dissection isolating the mass was performed and it was removed fully in two fragments. The mucosal incision was then closed with a suture.
The patient was discharged home the same day. Pathology showed ectopic pancreas with a retention cyst in one fragment and a submucosal lipoma in the other fragment (both with negative margins). No further intervention was required.
Discussion: STER is a novel endoscopic technique for removal of subepithelial masses first described in 2012. STER is a minimally invasive alternative to current surgical methods commonly used in the United States which have higher morbidity and longer recovery.
This case highlights a diagnostic challenge that can be encountered in gastric subepithelial masses. The mass did not have endoscopic or EUS features characteristic of common diagnoses such as pancreatic rest, lipoma, NET, or gastrointestinal stromal tumor (GIST). The presence of a retention cyst within the pancreatic rest was atypical and an adjacent second mass of lipoma complicated the EUS diagnosis. STER helped with the diagnosis and proved to be therapeutic obviating the need for a partial gastrectomy.
STER can be an invaluable organ-sparing method for diagnosis and treatment of gastric subepithelial tumors.
Figure: A) Subepithelial mass B) EUS image demonstrating 2cm lesion with cystic component beneath superficial layer of muscularis propria C) Subepithelial mass within the submucosal tunnel D) Removed Specimen E) Cyst wall with pancreatic acini and periductal mucinous glands F) Retention cyst with pancreatic epithelial lining
Brenna Welman indicated no relevant financial relationships.
Ian Holmes indicated no relevant financial relationships.
Sana Sultan indicated no relevant financial relationships.
Jia-Ling Huang indicated no relevant financial relationships.
Anand Kumar: Olympus America – Consultant.
Brenna Welman, BA1, Ian Holmes, MD2, Sana Sultan, MBBS3, Jia-Ling Huang, MD2, Anand R. Kumar, MD, MPH2. P1748 - Submucosal Tunneling Endoscopic Resection (STER) of a Complex Indeterminate Gastric Subepithelial Mass, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.