Heterotopic Gastric Mucosa at the Duodenojejunal Junction: A Rare Lesion Prone to Misdiagnosis as a Tumor

Heterotopic Gastric Mucosa at the Duodenojejunal Junction: A Rare Lesion Prone to Misdiagnosis as a Tumor | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Heterotopic Gastric Mucosa at the Duodenojejunal Junction: A Rare Lesion Prone to Misdiagnosis as a Tumor Xiaodie X, peiji song This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8299471/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract An 18-year-old female patient presented with a 1-year history of postprandial abdominal distension and belching. Physical examination revealed no abnormalities. Upper gastrointestinal contrast examination revealed dilation of the intestinal tract at the duodenojejunal junction. Non-contrast and contrast-enhanced CT scans revealed a well-defined space-occupying lesion at the duodenojejunal junction, which exhibited enhancement characteristics identical to gastric mucosa. Gastroscopy identified a broad-based submucosal protrusion located 6 cm distal to the duodenal papilla, displaying features characteristic of gastric mucosa. Pathological examination confirmed the presence of heterotopic gastric mucosa. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Heterotopic gastric mucosa (HGM) refers to a congenital developmental anomaly where normal gastric mucosa is present in other parts of the digestive tract. The most common sites of occurrence include the esophagus, duodenum, and Meckel's diverticulum [ 1 – 3 ] . Clinical reports of HGM occurring in the distal duodenum and proximal jejunum are exceedingly rare. These lesions often present radiologically as polyps, laterally spreading lesions, submucosal masses, or other growth patterns [ 4 , 5 ] . Due to their particular growth patterns and clinical manifestations, they are highly susceptible to misdiagnosis as neoplastic lesions such as gastrointestinal stromal tumors or lymphoma. This article reports a case of extensive HGM located at the duodenojejunal junction, focusing on its clinical characteristics, diagnostic approach, and management strategy. Case Presentation An 18-year-old female patient was admitted to the hospital due to "recurrent postprandial abdominal distension and belching for 1 year". The symptoms were more pronounced in the morning and after meals. There was no hematemesis, melena, or weight loss. Physical examination revealed no positive signs. Laboratory investigations, including complete blood count, liver and kidney function tests, and tumor markers, were all within normal limits.Gastrointestinal contrast examination indicated a space-occupying lesion at the duodenojejunal junction, with significant dilation of the horizontal segment reaching a maximum diameter of 5.3 cm, and a faint pen-like impression was vaguely visible (Fig. 1 ). Contrast-enhanced CT scan revealed an oval-shaped space-occupying lesion at the duodenojejunal junction, measuring approximately 5.2 cm × 3.3 cm × 1.9 cm, with well-defined borders. Post-enhancement, the degree of enhancement was similar to that of normal gastric mucosa. The lesion protruded into the intestinal lumen, causing significant luminal narrowing (Fig. 2 ).Axial (A-B) and sagittal (C-D) T2-weighted MR images confirm the presence of the submucosal mass, showing intermediate T2 signal intensity(Fig. 3 ). Gastroscopy identified a broad-based submucosal protrusion in the distal descending duodenum. The surface mucosa was smooth, occupying approximately two-thirds of the intestinal lumen. Under narrow-band imaging (NBI), typical gastric pit structures were observed(Figure 4 ). Based on the diagnosis, the patient received conservative treatment. Discussion Heterotopic gastric mucosa in the duodenum refers to a congenital condition where the full thickness of the duodenal mucosa is covered by fundic-type gastric mucosa containing numerous parietal and chief cells [ 6 ] , more commonly seen in adults. Most scholars believe it is related to abnormal migration of foregut cells during embryonic development^[7]^. The presence of oxyntic glands facilitates the secretion of gastric acid and pepsin, which may contribute to clinical symptoms. However, due to the neutralization of gastric acid and pepsin by duodenal juices, the clinical symptoms of duodenal HGM are often atypical and are frequently discovered incidentally during gastroscopy. The particularity of this case lies in the patient's young age, absence of a history of chronic inflammation, extensive involvement of the lesion, and the formation of a significant tumor-like mass effect, favoring an explanation of congenital developmental anomaly. In terms of diagnosis, this case highlights the challenges in differentiating ectopic gastric mucosa (EGM) from neoplastic lesions such as gastrointestinal stromal tumors (GISTs) and lymphoma. The CT enhancement value of EGM is highly consistent with that of normal gastric mucosa and is significantly higher than that of GISTs. Under narrow-band imaging (NBI), typical gastric pit structures can be observed. Pathological characteristics include the presence of complete gastric gland structures but absence of a double muscle layer. These features constitute specific diagnostic criteria for EGM. The diagnostic process in this case suggests that for space-occupying lesions at the duodenojejunal junction, the possibility of heterotopic gastric mucosa should be considered. The core aspect of this case is the achievement of a precise preoperative diagnosis based on characteristic CT enhancement and endoscopic findings, thereby avoiding high-risk surgery. The duodenojejunal junction has a complex anatomical structure, closely adjacent to the uncinate process of the pancreatic head and supplied by the superior mesenteric vessels. Surgical dissection in this area can easily lead to uncontrollable bleeding and pancreatic injury. Postoperatively, the continuous erosion by digestive juices (pancreatic juice, bile) and high intestinal wall tension make anastomotic healing difficult, significantly increasing the risk of duodenal fistula or pancreatic fistula, with serious consequences. Therefore, for asymptomatic or mildly symptomatic HGM with imaging findings supporting a benign diagnosis, conservative management is preferable to surgical resection. Compared to cases reported in the literature [ 7 , 8 ] , the lesion in this case was more extensive. We suggest that for similar cases, treatment decisions should be individualized, comprehensively considering factors such as the extent of the lesion, severity of symptoms, and risk of malignant transformation. Conclusion Extensive heterotopic gastric mucosa at the duodenojejunal junction is a rare clinical entity that can form a tumor-like lesion and lead to clinical symptoms such as intestinal obstruction. Diagnosis of this lesion requires a combination of imaging, endoscopic, and pathological examinations, primarily for differentiation from various neoplastic lesions. Provided malignancy and severe complications are excluded, conservative treatment is a reasonable and safe first-line management option. Declarations Funding sources This research was supported by the Jinan Science and Technology Bureau Advanced Medical Technology Innovation Plan (202512008), the Jinan Central Hospital’s 2020 First-batch Research Fund for Introducing Talents (YJRC2020005), the Jinan Government 5150 Project for innovative Talents, and Medical and Health Science and Technology Development Plan Project of Shandong Province (202209010494). Conflict of Interest The authors declare no conflict of interest Ethical Approval and Consent to Participate This study was approved by the Ethics Committee of Jinan Central Hospital Affiliated to Shandong First Medical University (Approval No.: R20241008008. All procedures performed were in accordance with the ethical standards of the Helsinki Declaration. Written informed consent was obtained from the patient for publication of this case report and any accompanying images. References CHEN Y R, WU M M, NAN Q, et al. Heterotopic gastric mucosa in the upper and middle esophagus: 126 cases of gastroscope and clinical characteristics [J]. Hepatogastroenterology, 2012, 59(116): 1123-5. YU L, YANG Y, CUI L, et al. Heterotopic gastric mucosa of the gastrointestinal tract: prevalence, histological features, and clinical characteristics [J]. Scand J Gastroenterol, 2014, 49(2): 138-44. BEN BRAHIM E, JOUINI R, ABOULKACEM S, et al. [Gastric heterotopia: clinical and histological study of 12 cases] [J]. Tunis Med, 2011, 89(12): 935-9. TERADA T. Heterotopic gastric mucosa of the gastrointestinal tract: a histopathologic study of 158 cases [J]. Pathol Res Pract, 2011, 207(3): 148-50. GUO L J, YE L, HUANG Z Y, et al. Magnetic beads-assisted endoscopic submucosal dissection of duodenal heterotopic gastric mucosa with fibrosis [J]. Endoscopy, 2019, 51(5): E113-e5. NAKACHI K, NAGUMO H, OKURA T, et al. A case of duodenal pyloric gland adenoma with high-grade dysplasia arising from ectopic gastric mucosa [J]. DEN Open, 2026, 6(1): e70135. CHEN Y, CAO Y, ZHI L, et al. Endoscopic submucosal dissection combined surgery for the treatment of ectopic gastric mucosa and ectopic pancreas in muscularis propria and serosal layer of the stomach: A rare case report and review of the literature [J]. Medicine (Baltimore), 2025, 104(9): e41297. COHEN D L, BERMONT A, SHIRIN H. A systematic review of fully circumferential inlet patches (heterotopic gastric mucosa): More complicated than regular inlet patches [J]. Indian J Gastroenterol, 2025, 44(4): 443-56. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 02 Feb, 2026 Reviews received at journal 22 Jan, 2026 Reviewers agreed at journal 21 Jan, 2026 Reviews received at journal 18 Jan, 2026 Reviewers agreed at journal 18 Jan, 2026 Reviewers invited by journal 13 Jan, 2026 Editor invited by journal 24 Dec, 2025 Editor assigned by journal 21 Dec, 2025 Submission checks completed at journal 21 Dec, 2025 First submitted to journal 07 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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1","display":"","copyAsset":false,"role":"figure","size":312308,"visible":true,"origin":"","legend":"\u003cp\u003eGastrointestinal contrast examination showing a space-occupying lesion at the duodenojejunal junction.\u003c/p\u003e\n\u003cp\u003eAn upper gastrointestinal series reveals significant dilation of the horizontal segment of the duodenum, with a maximum luminal diameter of 5.3 cm. A faint, pen-like impression is visible within the dilated segment , suggesting an extrinsic or intramural mass effect\u003c/p\u003e","description":"","filename":"fig1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8299471/v1/1041401b11568b39b2b9002f.jpg"},{"id":100410322,"identity":"8c2d4bbb-83c8-4154-b793-992e990297af","added_by":"auto","created_at":"2026-01-16 13:08:12","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":312119,"visible":true,"origin":"","legend":"\u003cp\u003eContrast-enhanced CT scan at the duodenojejunal junction.\u003c/p\u003e\n\u003cp\u003e(A) Non-contrast CT image showing the lesion with a density of 33 HU. (B) Contrast-enhanced CT image showing significant enhancement of the lesion to 94 HU, similar to the enhancement pattern of normal gastric mucosa. The well-defined, oval-shaped mass protrudes into the intestinal lumen, causing significant luminal narrowing.\u003c/p\u003e","description":"","filename":"fig2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8299471/v1/e81fabdf1e30424f20287d01.jpg"},{"id":100410635,"identity":"5f1d272f-fad6-403a-b0a3-23819898824f","added_by":"auto","created_at":"2026-01-16 13:08:41","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":309160,"visible":true,"origin":"","legend":"\u003cp\u003eT2-weighted MR images of the submucosal mass.\u003c/p\u003e\n\u003cp\u003eDescription: (A-B) Axial and (C-D) sagittal T2-weighted MR images confirm the presence of a well-defined submucosal mass at the duodenojejunal junction, demonstrating intermediate T2 signal intensity.\u003c/p\u003e","description":"","filename":"fig3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8299471/v1/363cd03b422286d42923d6f8.jpg"},{"id":100409799,"identity":"f7e7fff8-38ee-4e6c-963a-a35dc5fa1c74","added_by":"auto","created_at":"2026-01-16 13:07:40","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":333599,"visible":true,"origin":"","legend":"\u003cp\u003eEndoscopic and narrow-band imaging (NBI) findings.\u003c/p\u003e\n\u003cp\u003eDescription: Gastroscopy identified a broad-based submucosal protrusion in the distal descending duodenum. The surface mucosa was smooth, occupying approximately two-thirds of the intestinal lumen. Under narrow-band imaging (NBI), typical gastric pit structures were observed, characteristic of heterotopic gastric mucosa.\u003c/p\u003e","description":"","filename":"fig4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8299471/v1/bdca68d3afb0acca67eb5b0e.jpg"},{"id":100546543,"identity":"d8a55b03-fe07-4422-aa85-8a0d81db697e","added_by":"auto","created_at":"2026-01-19 08:10:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1538372,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8299471/v1/f3565dcd-7672-4711-ad95-07fc337d1279.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Heterotopic Gastric Mucosa at the Duodenojejunal Junction: A Rare Lesion Prone to Misdiagnosis as a Tumor","fulltext":[{"header":"Introduction","content":"\u003cp\u003eHeterotopic gastric mucosa (HGM) refers to a congenital developmental anomaly where normal gastric mucosa is present in other parts of the digestive tract. The most common sites of occurrence include the esophagus, duodenum, and Meckel's diverticulum\u003csup\u003e[\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Clinical reports of HGM occurring in the distal duodenum and proximal jejunum are exceedingly rare. These lesions often present radiologically as polyps, laterally spreading lesions, submucosal masses, or other growth patterns\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. Due to their particular growth patterns and clinical manifestations, they are highly susceptible to misdiagnosis as neoplastic lesions such as gastrointestinal stromal tumors or lymphoma. This article reports a case of extensive HGM located at the duodenojejunal junction, focusing on its clinical characteristics, diagnostic approach, and management strategy.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eAn 18-year-old female patient was admitted to the hospital due to \"recurrent postprandial abdominal distension and belching for 1 year\". The symptoms were more pronounced in the morning and after meals. There was no hematemesis, melena, or weight loss. Physical examination revealed no positive signs. Laboratory investigations, including complete blood count, liver and kidney function tests, and tumor markers, were all within normal limits.Gastrointestinal contrast examination indicated a space-occupying lesion at the duodenojejunal junction, with significant dilation of the horizontal segment reaching a maximum diameter of 5.3 cm, and a faint pen-like impression was vaguely visible (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Contrast-enhanced CT scan revealed an oval-shaped space-occupying lesion at the duodenojejunal junction, measuring approximately 5.2 cm \u0026times; 3.3 cm \u0026times; 1.9 cm, with well-defined borders. Post-enhancement, the degree of enhancement was similar to that of normal gastric mucosa. The lesion protruded into the intestinal lumen, causing significant luminal narrowing (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).Axial (A-B) and sagittal (C-D) T2-weighted MR images confirm the presence of the submucosal mass, showing intermediate T2 signal intensity(Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Gastroscopy identified a broad-based submucosal protrusion in the distal descending duodenum. The surface mucosa was smooth, occupying approximately two-thirds of the intestinal lumen. Under narrow-band imaging (NBI), typical gastric pit structures were observed(Figure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Based on the diagnosis, the patient received conservative treatment.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eHeterotopic gastric mucosa in the duodenum refers to a congenital condition where the full thickness of the duodenal mucosa is covered by fundic-type gastric mucosa containing numerous parietal and chief cells\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e, more commonly seen in adults. Most scholars believe it is related to abnormal migration of foregut cells during embryonic development^[7]^. The presence of oxyntic glands facilitates the secretion of gastric acid and pepsin, which may contribute to clinical symptoms. However, due to the neutralization of gastric acid and pepsin by duodenal juices, the clinical symptoms of duodenal HGM are often atypical and are frequently discovered incidentally during gastroscopy. The particularity of this case lies in the patient's young age, absence of a history of chronic inflammation, extensive involvement of the lesion, and the formation of a significant tumor-like mass effect, favoring an explanation of congenital developmental anomaly. In terms of diagnosis, this case highlights the challenges in differentiating ectopic gastric mucosa (EGM) from neoplastic lesions such as gastrointestinal stromal tumors (GISTs) and lymphoma. The CT enhancement value of EGM is highly consistent with that of normal gastric mucosa and is significantly higher than that of GISTs. Under narrow-band imaging (NBI), typical gastric pit structures can be observed. Pathological characteristics include the presence of complete gastric gland structures but absence of a double muscle layer. These features constitute specific diagnostic criteria for EGM. The diagnostic process in this case suggests that for space-occupying lesions at the duodenojejunal junction, the possibility of heterotopic gastric mucosa should be considered. The core aspect of this case is the achievement of a precise preoperative diagnosis based on characteristic CT enhancement and endoscopic findings, thereby avoiding high-risk surgery. The duodenojejunal junction has a complex anatomical structure, closely adjacent to the uncinate process of the pancreatic head and supplied by the superior mesenteric vessels. Surgical dissection in this area can easily lead to uncontrollable bleeding and pancreatic injury. Postoperatively, the continuous erosion by digestive juices (pancreatic juice, bile) and high intestinal wall tension make anastomotic healing difficult, significantly increasing the risk of duodenal fistula or pancreatic fistula, with serious consequences. Therefore, for asymptomatic or mildly symptomatic HGM with imaging findings supporting a benign diagnosis, conservative management is preferable to surgical resection. Compared to cases reported in the literature\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e, the lesion in this case was more extensive. We suggest that for similar cases, treatment decisions should be individualized, comprehensively considering factors such as the extent of the lesion, severity of symptoms, and risk of malignant transformation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eExtensive heterotopic gastric mucosa at the duodenojejunal junction is a rare clinical entity that can form a tumor-like lesion and lead to clinical symptoms such as intestinal obstruction. Diagnosis of this lesion requires a combination of imaging, endoscopic, and pathological examinations, primarily for differentiation from various neoplastic lesions. Provided malignancy and severe complications are excluded, conservative treatment is a reasonable and safe first-line management option.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding sources\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was supported by the Jinan Science and Technology Bureau Advanced Medical Technology Innovation Plan (202512008), the Jinan Central Hospital\u0026rsquo;s 2020 First-batch Research Fund for Introducing Talents (YJRC2020005), the Jinan Government 5150 Project for innovative Talents, and Medical and Health Science and Technology Development Plan Project of Shandong Province (202209010494).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval and Consent to Participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Jinan Central Hospital Affiliated to Shandong First Medical University (Approval No.: R20241008008. All procedures performed were in accordance with the ethical standards of the Helsinki Declaration. Written informed consent was obtained from the patient for publication of this case report and any accompanying images.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCHEN Y R, WU M M, NAN Q, et al. Heterotopic gastric mucosa in the upper and middle esophagus: 126 cases of gastroscope and clinical characteristics [J]. Hepatogastroenterology, 2012, 59(116): 1123-5.\u003c/li\u003e\n\u003cli\u003eYU L, YANG Y, CUI L, et al. Heterotopic gastric mucosa of the gastrointestinal tract: prevalence, histological features, and clinical characteristics [J]. Scand J Gastroenterol, 2014, 49(2): 138-44.\u003c/li\u003e\n\u003cli\u003eBEN BRAHIM E, JOUINI R, ABOULKACEM S, et al. [Gastric heterotopia: clinical and histological study of 12 cases] [J]. Tunis Med, 2011, 89(12): 935-9.\u003c/li\u003e\n\u003cli\u003eTERADA T. Heterotopic gastric mucosa of the gastrointestinal tract: a histopathologic study of 158 cases [J]. Pathol Res Pract, 2011, 207(3): 148-50.\u003c/li\u003e\n\u003cli\u003eGUO L J, YE L, HUANG Z Y, et al. Magnetic beads-assisted endoscopic submucosal dissection of duodenal heterotopic gastric mucosa with fibrosis [J]. Endoscopy, 2019, 51(5): E113-e5.\u003c/li\u003e\n\u003cli\u003eNAKACHI K, NAGUMO H, OKURA T, et al. A case of duodenal pyloric gland adenoma with high-grade dysplasia arising from ectopic gastric mucosa [J]. DEN Open, 2026, 6(1): e70135.\u003c/li\u003e\n\u003cli\u003eCHEN Y, CAO Y, ZHI L, et al. Endoscopic submucosal dissection combined surgery for the treatment of ectopic gastric mucosa and ectopic pancreas in muscularis propria and serosal layer of the stomach: A rare case report and review of the literature [J]. Medicine (Baltimore), 2025, 104(9): e41297.\u003c/li\u003e\n\u003cli\u003eCOHEN D L, BERMONT A, SHIRIN H. A systematic review of fully circumferential inlet patches (heterotopic gastric mucosa): More complicated than regular inlet patches [J]. Indian J Gastroenterol, 2025, 44(4): 443-56.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8299471/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8299471/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAn 18-year-old female patient presented with a 1-year history of postprandial abdominal distension and belching. Physical examination revealed no abnormalities. Upper gastrointestinal contrast examination revealed dilation of the intestinal tract at the duodenojejunal junction. Non-contrast and contrast-enhanced CT scans revealed a well-defined space-occupying lesion at the duodenojejunal junction, which exhibited enhancement characteristics identical to gastric mucosa. Gastroscopy identified a broad-based submucosal protrusion located 6 cm distal to the duodenal papilla, displaying features characteristic of gastric mucosa. Pathological examination confirmed the presence of heterotopic gastric mucosa.\u003c/p\u003e","manuscriptTitle":"Heterotopic Gastric Mucosa at the Duodenojejunal Junction: A Rare Lesion Prone to Misdiagnosis as a Tumor","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-16 11:11:32","doi":"10.21203/rs.3.rs-8299471/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-02T11:11:54+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-23T02:18:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"245371599039068399536314771706149597799","date":"2026-01-21T12:33:39+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-18T15:19:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"80475470257085534914750027387785208328","date":"2026-01-18T15:04:05+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-13T10:41:16+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-24T09:30:39+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-22T03:15:18+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-22T03:15:02+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2025-12-07T11:32:21+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"701add7c-619c-449a-a3b3-3932ce252c92","owner":[],"postedDate":"January 16th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-16T09:24:29+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-16 11:11:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8299471","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8299471","identity":"rs-8299471","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}