Submucosal Mass Research Articles

S2379 Squamous Cell Carcinoma of the Gastroesophageal Junction as an Unusual Underlying Cause of Pseudoachalasia

Introduction: Achalasia is a rare esophageal motility disorder characterized by progressive dysphagia to solids and eventually liquids[1-2]. Pseudoachalasia refers to an achalasia secondary to an underlying etiology, such as masses, post-operative complications, or paraneoplastic syndromes[1-2]. The most common cause of pseudoachalasia is adenocarcinoma of the cardia or esophagus [1] however, we discuss a rare case that deviates from the typical etiology of esophageal cancer. Case Description/Methods: This is a 71-year-old male presenting with intermittent dysphagia for years with rapid progression for a month including intolerance of oral intake and 6-pound weight loss. On examination he was hemodynamically stable with a soft, nontender abdomen. His initial barium esophagram revealed decreased esophageal peristalsis, esophageal distention, and narrowing at the gastroesophageal junction (GEJ) with “bird beak” appearance consistent with possible achalasia. Further imaging studies were performed with computed tomography (CT), esophagogastroduodenoscopy (EGD) with dilation, and endoscopic ultrasound with biopsies revealing an invasive squamous cell carcinoma of the GEJ with submucosal involvement extending into the gastric cardia (Figure). We present our patient as the first reported case of pseudoachalasia due to SCC of the GEJ. The patient underwent esophageal stenting and mediport placement with plans for neoadjuvant chemotherapy with concurrent radiotherapy followed by definitive resection. Discussion: Pseudoachalasia is often misdiagnosed for primary achalasia because of its rarity, indistinguishable symptomatology, and normal findings on CT, EGD, and biopsy[1-2]. Nearly 75% of pseudoachalasia cases are due to adenocarcinoma of the gastric cardia[1]. Only one case of pseudoachalasia has been known to be caused by SCC in the distal esophagus[3]. SCC of the GEJ is an extremely rare esophageal malignancy and has never previously been reported as an underlying cause of pseudoachalasia.Figure 1.: Esophagogastroduodenoscopy revealed severe stricture at the GEJ with a 4 cm submucosal mass at the GEJ with extension to the gastric cardia.REFERENCES 1. Campo SM, Zullo A, Scandavini CM, Frezza B, Cerro P, Balducci G. Pseudoachalasia: A peculiar case report and review of the literature. World J Gastrointest Endosc. 2013;5(9):450-454. 2. Roushan N, Zolfaghari A, Asadi M, Taslimi R. Pseudoachalasia: a diagnostic challenge. Med J Islam Repub Iran. 2014;28:54. 3. Kahrilas, P., Kishk, S., Helm, J., Dodds, W., Harig, J. and Hogan, W., 1987. Comparison of pseudoachalasia and achalasia. The American Journal of Medicine. 1987;82(3):439-446.

S2021 Dilemma of a Rectal Mass

Introduction: Mucosal prolapsing polyps of the colon are uncommon findings during colonoscopy that are often misdiagnosed as malignant lesions that many times lead to unnecessary endoscopic and surgical resection. At times rectal prolapse/ mucosal prolapse syndrome can present as rectal submucosal mass similar to one another. Herein we present a case of a 63-year-old male with rectal prolapse that mimicked Submucosal rectal mass. Case Description/Methods: A 63-year-old male with prior medical history of hypertension, hyperlipidemia, obesity, treated Heliobacter pylori, hemorrhoids presented to the gastroenterology clinic due to 3-month history of dizziness, abdominal pain and bright red blood per rectum. Initial vitals were stable except for tachycardia. Physical examination was unremarkable except for external rectal hemorrhoids that were appreciated. Labs were also unremarkable on admission except for Normocytic anemia. Patient was planned and taken for colonoscopy which had poor bowel preparation, revealed large rectal mass, 2 small polyps in ascending and transverse colon which were resected. Patient was planned for flexible sigmoidoscopy and lower endoscopic ultrasound evaluation of rectal mass which revealed a hypoechoic, submucosal lesion measuring 14mm by 7mm. Patient underwent endoscopic submucosal resection of the rectal mass and removal of lesion. Post op he had rectal pain along with hypotension, which led patient to be admitted for overnight observation. On follow up patient complained of recurrent dizziness and BRBPR, sigmoidoscopy was planned and revealed superficial mucosal ulceration which was treated with bipolar cautery. Pathology of the rectal mass revealed largely denuded benign appearing congested polyp with granulation tissue and cautery artifacts. Patient’s symptoms improved on subsequent follow ups (Figure). Discussion: Mucosal prolapse presents as a common underlying mechanism rectal prolapse, inflammatory polyps, solitary rectal ulcer syndrome that were previously proposed to be grouped under the umbrella term “mucosal prolapse syndrome”. Mucosal prolapse can manifest as ulcerated, flat erythematous, or polypoid lesions. At times they can even mimic adenocarcinomas, adenomas both endoscopically and histologically. Most of the time rectal prolapses polyps have been seen in patients with mucosal prolapse syndrome. Thus, it is vital to differentiate and diagnose rectal prolapse versus true rectal mass in order to exclude malignancies. This will help guide management and surveillance strategy.Figure 1.: Nodules from Colonoscopy.

S2216 A Rare Case of Symptomatic Colonic Lymphangioma

Introduction: Lymphangiomas are benign lymphatic lesions, most frequently identified in the head and neck. Colonic lymphangiomas occur but are rare and represent less than 1% of all lymphatic malformations. These lesions are often asymptomatic and discovered incidentally during routine colonoscopy. We present a case of a symptomatic colonic lymphangioma manifesting as a large mass requiring surgical resection. Case Description/Methods: A 42-year-old male presented with the complaint of lower abdominal pain. Associated symptoms included nausea with no vomiting, and he denied family history of gastrointestinal malignancies. At presentation, vital signs were stable and abdominal exam was benign. Laboratory studies were unremarkable, but a Computed Tomography (CT) abdomen/pelvis with contrast revealed a 6.6 x 7 x 6.6 cm colonic mass near the hepatic flexure. Follow up colonoscopy demonstrated a large, subepithelial-appearing mass in the ascending colon protruding more than 90% into the lumen. Retroflexed view revealed 2 x 2 cm ulceration on the proximal aspect of the lesion. Serum tumor markers including CEA, CA 19-9, and CA 125 were all within normal limits and additional CT imaging revealed no metastatic lesions. Biopsies resulted back demonstrating superficial portions of colonic mucosa with mild focal inflammation. However, surgical evaluation was advised given the mass size and the patient thus underwent an elective laparoscopic right hemicolectomy. Tissue samples were sent for evaluation and revealed lymphangiomatosis/lymphatic malformation/cystic lymphangioma centered in the colonic submucosa with extension into the subserosal tissue. No cellular atypia or malignancy was identified, and 24 lymph nodes were benign. These pathology findings were confirmed by expert review at a tertiary center, where it was noted that this case also lacked features of congenital lymphangiectasia. During post-operative follow-up, the patient was reported to be progressing well (Figure). Discussion: Lymphangiomas have an incidence of less than 0.20% and intra-abdominal lymphangiomas represent only a fraction of cases. Although most colonic lymphangiomas are asymptomatic and identified incidentally, they can lead to an array of symptoms and severe complications such as obstruction, intussusception, and perforation requiring surgical intervention if large. Although colonic lymphangiomas are rare, it is important to be aware of their rising incidence to help facilitate accurate and timely diagnosis to prevent complications.Figure 1.: A. Colonoscopy. Submucosal mass in the ascending colon involving more than 90% of the circumference. Figure B. CT axial image. Mass in the ascending colon/hepatic flexure. Figure C. CT coronal image. Mass in the ascending colon/hepatic flexure. Figure D. CT sagittal image. Mass in the ascending colon/hepatic flexure.

S2436 A Rare Case of a Large Esophageal Gastrointestinal Stromal Tumor

Introduction: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms, accounting for approximately 1 to 2 percent of primary gastrointestinal (GI) cancers. Presenting symptoms include abdominal pain, nausea, vomiting, early satiety, bleeding, and dysphagia, but vary depending on primary tumor location. Most tumors are discovered incidentally with the majority found in the stomach (40 to 60 percent) followed by small bowel (25-30 percent), colon and rectum (5-15 percent). We present a case of an elderly patient diagnosed with esophageal GIST after he was found to have an incidental esophageal mass on imaging. Case Description/Methods: 80-year-old male with PMH of HTN, HLD, DM2, CKD Stage III, COPD, former tobacco user was referred for an upper endoscopy for evaluation of an incidental finding on CT scan. CT demonstrated a mass arising from the distal esophagus, measuring 6.5 x 7.5 cm. Patient denied any dysphagia, abdominal pain, nausea, vomiting, weight loss, hematemesis, or melena. Endoscopy showed submucosal mass in the distal esophagus (Figure). Biopsy was inconclusive and subsequent EUS-guided fine needle biopsy was performed. Upper endoscopic ultrasound (EUS) showed an intramural lesion in the distal esophagus arising from the muscularis propria. Pathology results confirmed GIST, positive for CD117 and DOG-1. Further testing revealed a mutation in the KIT gene exon 11. Patient is currently undergoing neoadjuvant therapy with imatinib mesylate with anticipated surgical resection. Discussion: This is a rare case of a large esophageal GIST. Most mesenchymal esophageal tumors are leiomyomas, and GIST only accounts for 0.7% of them. EUS with fine need aspiration biopsy is the most accurate method for diagnosis and definite diagnosis is made histologically. Majority of GISTs, expresses the CD117 antigen, a KIT receptor tyrosine kinase. Another commonly found mutation is the platelet derived growth factor (PDGFRA) tyrosine kinase gene. Tumor size and mitotic rate are used for prognostication, with increased malignancy risk seen in tumor size > 3 cm with irregular margins. Tumor location is also a key factor in risk stratification; non gastric primary location has higher rates of metastases. Liver and peritoneum are the most common sites of metastatic GISTs. Treatment focuses on surgical resection and neoadjuvant therapy with imatinib. Given significant implication for its management, esophageal GIST should be considered in differential diagnosis and distinguished from more common esophageal leiomyomas.Figure 1.: Submucosal mass in distal esophagus.

S3595 Gastric Glomus Tumors: Silent Until Ulcerated

Introduction: Glomus tumors are rare and mostly benign mesenchymal neoplasms comprising fewer than 2% of all soft tissue tumors. They arise from the modified smooth muscle cells (glomus cells) of the glomus body, an arteriovenous shunt typically found in peripheral soft tissue of the extremities. Rarely, glomus tumors can occur in the gastrointestinal (GI) tract, where they arise from the submucosa or muscularis propria. We present two interesting cases of gastric glomus tumor (GGT) with different clinical outcomes. Case Description/Methods: A 46-year-old female presented with shortness of breath and fatigue for 3 months. Labs showed iron deficiency anemia with a hemoglobin of 4.4 gm/dl. Esophagogastroduodenoscopy (EGD) revealed a large, ulcerated, partially circumferential mass in the gastric (Figure 1A, 1B) Imaging showed a solid 7.8 cm mass in the gastric antrum with multiple hepatic metastases. Gastric biopsy showed glomus tumor, with a positive smooth muscle actin (SMA) stain and abundant background necrosis. Liver biopsy also confirmed metastasis of the glomus tumor. Patient is currently undergoing chemotherapy to downsize the primary tumor before surgical intervention. A 72-year-old female with a history of breast cancer was admitted with hematemesis and melena. EGD revealed a large submucosal ulcerated gastric mass with signs of bleeding. Endoscopic ultrasound (EUS) showed the mass was arising from the muscularis propria, in the antrum of the stomach (Figure 2A, 2B) Fine needle aspiration was performed which expressed only synaptophysin (Syn), suggestive of gastric neuroendocrine tumor. Patient underwent an exploratory laparotomy and distal gastrectomy for continued GI bleeding. The tumor was sent for surgical pathology, which expressed both smooth muscle actin and Syn, confirming glomus tumor. The patient was stable following gastrectomy. Discussion: GGTs account for approximately 1% of all GI mesenchymal tumors and are difficult to differentiate from other richly vascularized tumors, such as gastrointestinal stromal tumor (GIST). The definitive diagnosis relies on EGD, histopathologic examination with immunohistochemical staining and EUS-guided fine-needle aspiration. Glomus tumor cells stain positive for SMA and vimentin, while Syn and CD34 can be positive in some cases. Surgical resection is the treatment of choice and offers a favourable prognosis. Metastatic spread as seen in one of our cases is extremely rare. There are no standard of care chemotherapeutic regimens for treatment of GGTs.Figure 1.: Two gastric glomus tumors seen on esophagogastroduodenoscopy (EGD) and endoscopic ultrasound (EUS).

S3514 A Case of Symptomatic Ileal Non-Secretory Neuroendocrine Tumor Successfully Treated With Octreotide

Introduction: Neuroendocrine tumor incidence is steadily increasing, likely from detection due to better imaging, routine colonoscopies, and endoscopies. Most NETs, 55%, are found in the GI tract and only 0.1-1% found on routine colonoscopy. About 40% of NETs are hormone producing leading to the clinical diagnosis of carcinoid syndrome. One of the most common symptoms of carcinoid syndrome is diarrhea occuring in 80% percent of cases, however diarrhea can be present in non-secretory NETs. Here we report a case of GNET presenting as diarrhea that responded to octreotide injections despite having normal 5-HIAA and chromogranin A levels. Case Description/Methods: Our patient is an 80 year old female with past medical history of hypertension, renal stones, and IBS with baseline diarrhea of about 2-4 pasty stools a day. In November she developed two days of severe diarrhea with 10 watery stools a day and multiple episodes of incontinence which prompted patient to go to the ED. The inpatient workup was negative for acute causes, CT showed diverticulosis, and stools returned to baseline. The patient was discharged with outpatient GI follow up. At home the severe diarrhea retuned so outpatient GI planned for colonoscopy. Results of the procedure included a 2cm submucosal non-obstructing mass in the terminal ileum. Pathology showed a G1 well differentiated neuroendocrine tumor. Patient was referred to oncology and workup revealed no metastasis on PET/CT and negative 5-HIAA and chromogranin A levels. During initial oncology visit patient was started on octreotide injections which greatly improved the diarrhea. Even with negative carcinoid workup the decision was made to continue octreotide injections and not to pursue surgical options. (Figure) Discussion: The terminal ileum is the most common GI location for NETs. Terminal ileum intubation on coloscopy is attempted 30-80% and greatly aids in diagnosis, as with our patient. Once diagnosed, there is limited guidance on treatment of diarrhea in patients with NETs and negative carcinoid workup. There are no abstracts or research on treatment of diarrhea with negative carcinoid syndrome. One treatment for carcinoid syndrome is somatostatin analogues but no guidelines with non-carcinoid NETs and therapeutic value in octreotide. However, with our patient, treatment with monthly octreotide injections resolved their symptoms. Our case emphasizes importance of ileal intubation in coloscopy and that somatostatin analogue treatment should be considered in non carcinoid NETs.Figure 1.: Small bowel (terminal ileum): well-differentiated neuroendocrine tumor (G1).

S3659 Primary Gastric Squamous Cell Carcinoma With Concurrent H. pylori Infection and Colonic Metastasis

Introduction: Primary gastric squamous cell carcinoma (PGSCC) is a rare, aggressive, malignancy that cannot be distinguished from other gastric malignancies clinically and therefore, requires EGD with biopsy and pathology. H. pylori infection is a known risk factor for gastric malignancies but, only one case has been reported with an association between the two. Case Description/Methods: 66-year-old Hispanic male, with no significant medical, family, or social history presented to the hospital with syncope. Further history revealed three weeks of melena, fatigue, exertional dyspnea, and 50 lb weight loss. Upon evaluation, the patient was found to have HGB of 3.2. CT abdomen with contrast showed a mass in the antrum of the stomach, most prominent posteriorly and around the greater curvature. EGD revealed normal esophagus and a 15 cm, oozing, fungating, and partially circumferential gastric mass. It was located in the antrum, involving the entire posterior wall with extension into the greater curvature. The gastric mass was 5 cm below the GE junction, without evidence of esophageal involvement. Biopsy of the mass revealed poorly differentiated squamous cell carcinoma and Helicobacter pylori infection. Colonoscopy then revealed a 4 cm lesion near the splenic flexure which was confirmed to also be poorly differentiated squamous cell carcinoma. The patient was placed on triple therapy for his H. pylori infection. PET scan showed known gastric and colonic mass with multiple enlarged and hypermetabolic perigastric and retroperitoneal lymph nodes consistent with metastasis. He was seen by oncology and started on systemic chemotherapy (Figure 1). Discussion: PGSCC is a rare form of gastric malignancy accounting for roughly 0.2% of primary gastric cancer reported. Compared to the more common gastric adenocarcinoma, SCC tends to be more aggressive with poorer outcomes. Unfortunately, the pathogenesis remains obscure, making early detection difficult. Our case was associated with H. pylori infection which is one of the most significant risk factors for the development of gastric cancer due to the chronic inflammation caused by infection. Additionally, metastasis to the colon is exceptionally rare with most cases metastasizing to liver, peritoneum, lung and bone. Further investigation and studies are needed to understand this rare disease.Figure 1.: Primary gastric tumor (left panel), submucosal colonic mass (right panel).

S2576 Application of Hemospray for Metastatic Bleeding Gastric Adenocarcinoma: A Case Report

Introduction: TC-325 hemostatic powder (Hemospray) is a mineral-based topical agent that acts as a mechanical barrier over a bleeding site. It is a non-invasive, safe, and effective modality in controlling active GI bleeding, with immediate response. Here, we present a case of bleeding metastatic gastric adenocarcinoma managed with Hemospray after the failure of standard endoscopic therapy. Case Description/Methods: A 64-year-old male presented to the emergency room (ER) for symptomatic anemia. His hemoglobin was 4.6 g/dL. CT imaging showed gastric cardia lesion with multiple hepatic metastases. After blood transfusion, EGD (Figure 1a) showed a cardia lesion with oozing blood from multiple sites. Endoscopic ultrasound with fine-needle aspiration, showing atypical cells. The patient continued to have melena requiring transfusions. CT angiogram was negative. Partial gastrectomy was not performed due to peritoneal carcinomatosis. Endoscopic hemostasis with epinephrine and clips failed (Figure 1b). Hemospray was deployed (Figure 1c) with an immediate response. Later patient underwent left gastric artery embolization (Figure 1d), liver biopsy and peritoneal node sampling that suggested metastatic adenocarcinoma with primary gastric malignancy. The patient and his family opted for palliative care and was discharged. Discussion: Gastric cancer accounts for 2-8% of overall UGIB and 58% bleeding risk compared to other GI malignancies. There are no specific guidelines and only limited evidence was available on managing malignancy-related UGIB. Nonresponsive, inoperable metastatic gastric cancer bleeding is challenging and extremely difficult to manage using conventional hemostasis techniques. Based on our case, we recommend utilizing Hemospray as a first-line, monotherapy or in combination to control bleeding until a definitive treatment, reducing morbidity and mortality.Figure 1.: (A) Submucosal gastric fundal mass distal to gastroesophageal junction with blood oozing from multiple sites (arrows), (B) Image showing endoscopic hemostatic clips placement (arrowheads), (C) Application of Hemospray over the Gastric Mass after unsuccessful attempts using standard-of-care hemostatic methods, (D) Showing embolization of the left gastroepiploic artery.

S3378 Bleeding GIST Treated Successfully With Hemospray in a Patient With Neurofibromatosis Type 1

Introduction: Gastrointestinal stromal tumors (GISTs) are rare subepithelial mesenchymal neoplasms of the gastrointestinal tract that are typically KIT (CD117) positive. GISTs can present with a wide range of symptoms including gastrointestinal hemorrhage. Small bowel bleeding from a GIST can be difficult to treat endoscopically and there is a paucity of data on the use of TC-325 (hemospray) for these tumors. Case Description/Methods: A 47-year-old man with a past medical history significant for neurofibromatosis type 1 and multifocal small bowel GISTs presented to our center with symptomatic anemia. The patient described previous episodes of melena. The patient's initial hemoglobin was 2.2 g/dl. He was initially treated with a transfusion of 4 units packed red blood cells. CT abdomen and pelvis with IV contrast was obtained which revealed a centrally located 6 x 5cm small bowel mass with heterogeneous enhancement and intraluminal signal concerning for active gastrointestinal hemorrhage. A push enteroscopy was performed using a pediatric colonoscope via the mouth and advanced deeply into the small bowel. A large ulcerated submucosal mass with active bleeding was found at the junction of the fourth portion of the duodenum and proximal jejunum. Submucosal injection of 1:10,000 diluted epinephrine around the ulcer base failed to achieve hemostasis. Next, the hemospray catheter was advanced to several centimeters proximal to the bleeding ulcer. Hemospray was deployed and immediate hemostasis was achieved after coating the area. Discussion: The majority of GISTs are sporadic and found in the stomach. Patients with neurofibromatosis type 1 however, have a higher incidence of GISTs, are often multifocal, and most commonly are found in the small intestine as demonstrated here. Endoscopic treatment of small bowel tumor bleeding is challenging because of the location and nature of the bleeding. Conventional treatments such a hemoclips or bipolar electrocautery usually fail to stop tumor bleeding. TC-325 or hemospray is a novel inert powder which accelerates the coagulation cascade leading to rapid hemostasis of actively bleeding lesions. Hemospray should be considered first line treatment for malignant bleeding because of its ease of use, wide field of application and demonstrated success.

S2825 Endoscopic Management of an Obstructing Duodenal Wall Hematoma in the Setting of Acute Pancreatitis

Introduction: Spontaneous duodenal wall hematoma is a rare condition which can be associated with acute and chronic pancreatitis. It is often complicated by small bowel obstruction. When conservative management fails, options are limited. Here we describe a case of small bowel obstruction secondary to pancreatitis-associated duodenal wall hematoma which was successfully managed endoscopically through cystduodenostomy. Case Description/Methods: A 69-year-old male with HIV and normal CD4 count presented with acute abdominal pain and non-bloody emesis with elevated lipase of 374 U/L (ULN 82). Computed tomography revealed a 5.8 cm multilobulated pancreatic pseudocyst with associated inflammation and coarse calcifications and a 10 cm circumferential submucosal mass within the duodenum with significant luminal narrowing and compression of the adjacent inferior vena cava (a). Endoscopic ultrasound confirmed a homogenous, hypoechoic subepithelial lesion obstructing the second portion of the duodenum consistent with a hematoma (b). A nasogastric-jejunal tube was placed for feeding and decompression. Due to persistent obstruction and IVC compression, on hospital day 10 endoscopic drainage of the duodenal hematoma was performed via cystduodenostomy with a 15x10 mm electrocautery-enhanced lumen-apposing metal stent (LAMS) (AXIOS, Boston Scientific, Marlborough, MA, USA) (c). The LAMS was immediately removed after near-complete evacuation of the hematoma cavity to minimize the risk of bleeding complications. A plastic double-pigtail stent was left in place to facilitate complete drainage. The duodenum was then dilated with a 12-13.5-15mm hydrostatic balloon dilator. The pigtail stent was removed 3 days later with clinical, radiographic, and endoscopic resolution of the duodenal obstruction (d). Discussion: Duodenal hematoma is a previously described rare complication of pancreatitis. Endoscopic evacuation was a safe and effective means of relieving the duodenal obstruction in this patient. This minimally invasive option resulted in immediate resolution and can be considered when conservative management fails.Figure 1.: 10 cm duodenal wall hematoma on CT scan (a) and endoscopy (b). Endoscopic drainage via cystduodenostomy with a lumen-apposing metal stent (c). Resolution of the duodenal wall hematoma (d).

S2814 Diverting Disaster: EUS-Guided Trans-Gastric Biliary Drainage

Introduction: Lumen-apposing metal stents (LAMS) are a relatively new intervention that can be used for high risk surgical cases, such as malignant obstructions not amenable to ERCP. There are few case reports using LAMS with Endoscopic Ultrasound (EUS) to achieve drainage and palliative therapy in these situations, especially using a gastric over duodenal approach. In this case, we add to the growing body of literature supporting a transgastric approach for biliary drainage using LAMS. Case Description/Methods: A 73 year-old male was admitted due to concerns for obstructive jaundice. He presented with pruritis, nausea, vomiting, copious nasogastric tube bilious output and a total bilirubin of 19.8mg/dL. MRCP revealed a distal CBD stricture measuring 12 mm in length, marked intrahepatic and extrahepatic biliary dilatation and an 8mm dilated pancreatic duct. EGD revealed a submucosal mass within the duodenal bulb causing gallbladder impingement (a). EUS was then completed and revealed similar findings to MRCP including an atrophic pancreas and severely dilated gallbladder (b). The ampullary mass, noted on CT, was also identified under EUS and fine needle biopsy was performed. A 10mm x 10mm LAMS was placed under endoscopic and fluoroscopic visualization within the flanges in the gallbladder and the antrum of the stomach (c) and resolved the patient’s symptoms the next day. Surgical pathology demonstrated pancreatic ductal carcinoma of the major and minor papillae, pancreatic head and uncinate process. Discussion: Interventions for obstructive jaundice include ERCP with biliary stenting, percutaneous transhepatic biliary drainage, EUS with LAMS placement, as well as surgery. While ERCP is the first line option, the patient’s distorted ampullary anatomy would have made cannulation and stenting challenging and high risk. Percutaneous drainage would expose the patient to risk of dislodging, obstructing, leaking, and infection. Seen below, LAMS has a relatively large diameter which allows for immediate biliary drainage, proven by the patient’s rapid relief of symptoms. Since a duodenal approach is more commonly used, current literature displays only a small number of cases showcasing the technical success of gastric approach for CBD access via LAMS, for instance, in the setting of duodenal stenosis. Our case demonstrates the versatility of the Axios stent with another successful alternative approach and proves a transgastric approach with LAMS is a viable alternative to surgery for malignant obstructive jaundice.Figure 1.: Image a: Dilated minor and major papillae with evidence of duodenal obstruction. b: EUS view of the dilated gallbladder. c: Biliary drainage from gallbladder after LAMS placement.

Tongue Schwannoma, an Uncommon Oral Cavity Mass

Schwannomas are benign tumors arising from the Schwann cells, located in the peripheral nerve sheath. The incidence of tumor in the oral cavity is <1%, and the tongue is the most prevalent place in that area. A 32-year-old Hispanic female was sent from the otolaryngology department with a diagnosis of an oral mucocele in the oral cavity floor, after 8 months complaining of dysphonia and dysphagia. Physical examination reveals a submucosal mass in the anterior and ventral portion of the tongue. After characterization with magnetic resonance and biopsy guided by tomography, she underwent surgical management, with no complications. Tongue schwannomas are often misdiagnosed based on their very low incidence. A proper approach including a good physical examination, imaging and histological characterization of the lesion, and proper surgical management of this entity, will lead to cure this condition, with a low relapse rate.

S3601 Gastric Inflammatory Myofibroblastic Tumor Presenting as Chronic Abdominal Pain in a Young Female

Introduction: Inflammatory Myofibroblastic Tumor (IMT) is a rare mesenchymal tumor, commonly seen in children and adolescents. Lung is the most common site. Here we present an extremely rare case of a gastric IMT in a 28 year old lady. Case Description/Methods: Pt presented with intermittent epigastric pain for 8 years. This was associated with bloating and regurgitation and weight loss.These symptoms worsened along with new symptoms of chest pain, Cardiology workup was unremarkable. CT abdomen with contrast ordered to investigate further revealed 3.9 cm x 3.6 cm intramural mass with smooth margin and areas of internal calcification, extending into the gastric lumen of the upper stomach at the left lateral fundal region. Pt was referred to a local gastroenterologist. EGD performed showed confirmation of the lesion. Pt was referred to surgical oncologist at tertiary care hospital. EGD performed with biopsy of the lesion showed Benign gastric mucosa with small separate fragment of gastric mucosa containing smooth muscle-like tissue consistent with a tangentially section muscularis mucosa vs benign smooth muscle mass. Given the inconclusive diagnosis, partial gastrectomy was performed after detailed discussion with the patient. Gross pathology showed a submucosal mass, corresponding to the serosa lesion, measuring 4.3 x 4.2 x 3.7 cm. Microscopic pathology showed spindle cells with variable Cellularity with prominent lymphoplasmacytic infiltrates along with dystrophic calcification and osseous metaplasia. There is regional expression of ALK-1,and regional subserosal expression of SMA and MSA. Lesional cells do not express CD117, DOG-1, and desmin. The immunoprofile supports interpretation of IMT. Patient was seen eight months post surgery with resolution of all the symptoms. (Figure) Discussion: Primary gastric IMT is extremely rare. There have been a handful of cases in literature. Gastric IMT is most commonly associated with abdominal pain and upper GI bleeding. Most common treatment is partial gastrectomy. There is some potential of IMT to turn into malignancy. IMT are associated with high local recurrence rates. There are no guidelines on surveillance though common consensus is to perform EGD 6 months to a year initially followed by increasing the interval later. As GI clinicians, we should be aware of these symptoms associated with IMT.Figure 1.: CT images and Histology.

S1678 Gastric Ectopic Pancreas With Pseudocyst Formation Causing Gastric Outlet Obstruction

Introduction: Ectopic pancreas (EP) is a rare entity referring to the presence of pancreatic tissue at an anatomic location distinct from the pancreas which is commonly asymptomatic and found incidentally. EP can become symptomatic due to similar pathologic changes found in the anatomic pancreas including pancreatitis, bleeding, or pseudocyst formation. Gastric EP lesions present a diagnostic challenge as they lack distinguishing imaging and endoscopic features from other types of gastric submucosal tumors. This case report describes a rare case of EP presenting as a gastric antral mass with a unique combination of complications: chronic pancreatitis and pseudocyst formation causing gastric outlet obstruction. Case Description/Methods: A 59-year-old man presented to the hospital with nausea, vomiting, weight loss, and epigastric pain for 5 days. Exam was notable for epigastric tenderness, and labs were unremarkable. Computed tomography (CT) and index upper endoscopy showed a 4.4 x 3.5 cm multiloculated cystic mass in the gastric antrum (Figure). Endoscopic ultrasound (EUS) showed that the lesion originated from the submucosa, and fine needle aspiration (FNA) demonstrated histiocytes and epithelial cells with a high amylase level. On repeat endoscopy, interval growth of the cystic gastric mass was observed, and repeat CT abdomen/pelvis again showed the mass now with multiple cystic collections causing mass effect on a distended stomach suggesting gastric outlet obstruction. The lesion was surgically resected and determined to be EP with histologic changes of chronic pancreatitis and multiple pseudocysts. Patient did well after surgical resection and had no recurrence on repeat upper endoscopy. Discussion: EP can occur anywhere in the GI tract but most commonly are found in the duodenum or stomach. Symptoms are associated with the location, size, and pathology of the tissue. Lesions greater than 1.5 cm are more likely to be symptomatic with non-specific symptoms such as epigastric pain, abdominal fullness, nausea, diarrhea or melena. Diagnosis can be challenging, and in this case, multiple diagnostic modalities (imaging, endoscopy, EUS with FNA biopsy and surgical resection) were needed to reach a definitive diagnosis. EP is often found incidentally, and the combination of pseudocyst formation and gastric outlet obstruction in this case has been rarely reported in the literature. Prompt recognition of ectopic pancreas can facilitate the management of these complications.Figure 1.: A: Computed tomography of abdomen and pelvis from initial presentation, showing a multiloculated cystic mass (noted by *) and thickening of the gastric antral wall. B: Esophagogastroduodenoscopy (EGD) image showing a submucosal mass in the gastric antrum. C: Endoscopic ultrasound of gastric antrum with multicystic lesion appearing to originate from the submucosa.

Gastric submucosal mass lesions.

Gastric submucosal mass lesions are a collection of tumours that arise in the stomach and are deep to the mucosal layer. Distinct from gastric epithelial carcinomas, these tumours are generally more indolent. They are often found incidentally on upper endoscopy. Most often they present as smooth protuberant masses covered by normal intact gastric mucosa. The majority are asymptomatic. Endoscopic ultrasound (EUS) is frequently employed to further characterize the lesions. EUS can be diagnostic of some lesions, such as lipomas, and can be used to guide fine needle aspiration to diagnose others. Adding to the traditional management approaches of observation and surgical resection, numerous new and emerging endoscopic therapies are now being used to resect these gastric tumours. This review focuses on evolving strategies in the diagnosis and management of submucosal mass lesions. Although surgical intervention was once the lone option for intervention, there are an increasing number of endoscopic therapies. There have also been advancements in neoadjuvant therapies and in distinguishing the malignant potential of submucosal mass lesions. Gastric submucosal lesions are common. EUS is frequently indicated in the evaluation and diagnosis. For tumours for which observation is not recommended, novel endoscopic therapies may offer less invasive management options.

Efficacy and Safety Analysis of Submucosal Tunnel Endoscopic Resection for Submucosal Masses in Esophageal Muscularis Propria.

Objective To analyze the efficacy and safety of submucosal tunnel endoscopic resection (STER) for the treatment of submucosal masses in esophageal muscularis propria. Method A total of 272 patients with submucosal masses in esophageal muscularis propria diagnosed and treated in our hospital from February 2019 to January 2022 were randomly selected for the study and then were randomly divided into the STER group (n = 136) and the endoscopic mucosal dissection (ESD) group (n = 136) according to the random number table method. Patients in the STER and ESD groups were treated with STER and ESD, respectively. The clinical data of patients from the two groups were collected and compared. The clinical effects and the changes of surgery-related indexes of patients after ESD and STER treatment were observed. The safety of ESD and STER was compared. The factors influencing the efficacy of STER treatment for submucosal masses in esophageal muscularis propria were analyzed. Result There were significant differences between the STER group and the ESD group in terms of tumor size, lesion level, adhesion and surgical approaches (P < 0.05). The effective rates of ESD treatment and STER treatment were 98.53% and 88.97%, respectively. Meanwhile, the effective rates of STER treatment were significantly higher than those in the control group (P < 0.05). In addition, the patients in the STER group had longer operation time, less blood loss, and shorter hospital stay compared with those in the ESD group (P < 0.05). Adverse reactions occurred during ESD treatment and STER treatment included delayed bleeding, adhesion, perforation, and pleural effusion with the total incidence of adverse reactions of 4.41% and 13.97%, respectively. The adverse reactions in STER group were prominently less than these in the ESD group (P < 0.05). Logistic multivariate regression analysis showed that independent risk factors, including tumor size, lesion level, adhesion, and surgical approaches, affected the efficacy of STER in the treatment of submucosal masses in esophageal muscularis propria (P < 0.05). Conclusion STER is an effective method for the treatment of submucosal masses in esophageal muscularis propria, which can exhibit a good effect with faster postoperative recovery and higher safety, thereby being worthy of clinical application and promotion. Tumor size, lesion level, adhesion, and surgical approaches are all related factors affecting the effect of STER treatment.

Isolated hypopharynx lipoma: a case presentation and literature review

BackgroundLipomas are the most common benign mesenchymal tumors. They are defined as subcutaneous neoplasms of mature adipocyte cells that can occur wherever fatty tissue is. Lipomas are rare in the upper aerodigestive tract. Usually asymptomatic, they may be painful, uncomfortable, or even life-threatening especially if voluminous and located in the upper aerodigestive tract.Case presentationA 67-year-old female patient has presented with dyspnea on mild effort and chronic orthopnea. The physical examination was normal while the fiber optic endoscopy revealed a submucosal round-shaped mass rising from the left side of the post-cricoid region. CT scan revealed a well-circumscribed fatty mass of the left piriform sinus for which the patient underwent an endoscopic transoral approach for a complete removal with good results.Discussion and conclusionPharyngeal lipomas are rare entities that might be life-threatening. Although clinical manifestations are not specific, imaging techniques, especially MRI, help set the diagnosis showing a fatty mass of the upper aerodigestive tract. However, pathology examination is crucial to rule out low-grade liposarcomas. Surgical management is not well-codified and has benefited from the development of endoscopic techniques.

Cholangioscopic diagnosis of biliary amyloidosis presenting as bile duct obstruction with cholangitis (with video)

A 73-year-old woman with a history of cardiac amyloidosis presented with obstructive jaundice and upper right postprandial abdominal pain. Computed tomography yielded findings suggestive of common bile duct stones with acute cholangitis. A cholangiogram demonstrated 2 oval filling defects in the common bile duct (A). Intraductal US revealed hypoechoic, homogenous submucosal mass lesions (B). Single-operator cholangioscopy (SpyGlass DS II, Boston Scientific, Marlborough, Mass, USA) showed a protruding mass lesion with tortuous and dilated vessels and central ulceration (C) (Video 1, available online at www.giejournal.org). SpyBite Max forceps biopsy was performed to confirm the pathologic diagnosis. Analysis of the biopsy specimen revealed pink-red deposits in the area of eosinophilic material, consistent with amyloidosis (D, Congo red stain, orig. mag. ×200).

Acute pancreatitis following endoscopic ultrasonography-guided tissue acquisition for gastric ectopic pancreas.

A 37-year-old man was referred to our hospital for further evaluation of the gastric subepithelial lesion accidentally found during screening gastroscopy. The lesion was located on the greater curvature of the gastric body (Fig. 1a). Abdominal computed tomography (CT) demonstrated a 25-mm-diameter homogenously enhanced mass in the gastric wall (Fig. 1b). Endoscopic ultrasonography (EUS) showed a heterogeneous submucosal mass in the 3rd layer of the gastric wall (Fig. 1c). EUS-guided tissue acquisition (EUS-TA) was performed in three passes using a 22-gage Franseen needle (Acquire; Boston Scientific, Marlborough, MA, USA).

An unusual case of lymphoepithelial cyst of palatine tonsil

Amongst the various cystic lesions of oral cavity, Lymphoepithelial cyst (LEC) is a rare cystic lesion that presents as an asymptomatic submucosal mass and is usually discovered during routine oral examinations. Most common site of occurence is the floor of the mouth but tonsillar involvement seems to be very rare. Pathogenesis involves the excessive accumulation of desquamated epithelial lining in the tonsillar crypt. This results in a dilated obstructed crypt of the palatine tonsil region which presents as a cystic lesion. Here we are reporting a case of 17 year old female with lymphoepithelial cyst of tonsil.