{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T17:14:33Z","timestamp":1783358073030,"version":"3.54.6"},"reference-count":6,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2019,3,20]],"date-time":"2019-03-20T00:00:00Z","timestamp":1553040000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Histopathology"],"published-print":{"date-parts":[[2019,5]]},"abstract":"<jats:sec><jats:title>Aims<\/jats:title><jats:p>Inverted appendices are rare, but have the potential to cause diagnostic confusion among endoscopists and pathologists. The aim of this study was to describe the clinicopathological features of inverted appendices seen at our institution over the last 30\u00a0years.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods and results<\/jats:title><jats:p>Twenty\u2010one inverted appendices were identified and the clinical and pathological features reviewed. Patients were predominantly middle\u2010aged women. Most cases were detected incidentally on colonoscopy. Endoscopically, inverted appendices appeared polypoid in the proximal caecum. All resections featured associated pathological processes, including endometriosis (<jats:italic>n<\/jats:italic>\u00a0=\u00a03), inflammatory mucocoele (<jats:italic>n<\/jats:italic>\u00a0=\u00a01), low\u2010grade appendiceal mucinous neoplasm (<jats:italic>n<\/jats:italic>\u00a0=\u00a02), traditional serrated adenoma (<jats:italic>n<\/jats:italic>\u00a0=\u00a01) and inflammatory fibroid polyp (<jats:italic>n<\/jats:italic>\u00a0=\u00a01). Five cases were endoscopically mischaracterised as caecal polyps and removed via polypectomy; initial pathological impressions were erroneous in most cases. All polypectomies featured a dome\u2010like configuration covered by mucosa on the convex surface; the majority had aggregates of ganglion cells and neural plexi embedded in muscularis propria. The vast majority of cases, regardless of the procedure, showed lymphoid aggregates. Among post\u2010polypectomy patients with follow\u2010up, none experienced perforation\u2010associated morbidity despite the histological presence of muscularis propria.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>The diagnosis of an inverted appendix should be considered in polypectomy specimens from the caecum or appendiceal orifice with (i) dome\u2010like tissue configuration covered by mucosa on the convex surface, (ii) a deep, robust smooth muscle component with ganglion cells (muscularis propria) and (iii) associated lymphoid aggregates. Prompt recognition on H&amp;E will avoid unnecessary time and resource investment.<\/jats:p><\/jats:sec>","DOI":"10.1111\/his.13824","type":"journal-article","created":{"date-parts":[[2019,1,23]],"date-time":"2019-01-23T21:47:48Z","timestamp":1548280068000},"page":"853-860","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["The inverted appendix \u2013 a potentially problematic diagnosis: clinicopathologic analysis of 21 cases"],"prefix":"10.1111","volume":"74","author":[{"given":"Jacqueline","family":"Birkness","sequence":"first","affiliation":[{"name":"Department of Pathology Johns Hopkins University School of Medicine Baltimore MD USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dora","family":"Lam\u2010Himlin","sequence":"additional","affiliation":[{"name":"Department of Pathology Mayo Clinic Phoenix AZ USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kathleen","family":"Byrnes","sequence":"additional","affiliation":[{"name":"Department of Pathology Johns Hopkins University School of Medicine Baltimore MD USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Wood","sequence":"additional","affiliation":[{"name":"Department of Pathology Johns Hopkins University School of Medicine Baltimore MD USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2611-7576","authenticated-orcid":false,"given":"Lysandra","family":"Voltaggio","sequence":"additional","affiliation":[{"name":"Department of Pathology Johns Hopkins University School of Medicine Baltimore MD USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2019,3,20]]},"reference":[{"key":"e_1_2_7_2_1","first-page":"265","article-title":"71,000 human appendix specimens. A final report, summarizing forty years\u2019 study","volume":"14","author":"Collins DC","year":"1963","journal-title":"Am. J. Proctol."},{"key":"e_1_2_7_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.amjsurg.2008.08.023"},{"key":"e_1_2_7_4_1","doi-asserted-by":"publisher","DOI":"10.1308\/147870810X12699662981591"},{"key":"e_1_2_7_5_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1440-1827.1995.tb03393.x"},{"key":"e_1_2_7_6_1","first-page":"193","article-title":"An unusual \u2018tumor\u2019 of the cecum: the inverted appendiceal stump","volume":"47","author":"Taban S","year":"2006","journal-title":"Rom. J. Morphol. Embryol."},{"key":"e_1_2_7_7_1","first-page":"556","article-title":"Endoscopic removal of an intussuscepted appendix mimicking a polyp \u2013 an endoscopic hazard","volume":"77","author":"Fazio RA","year":"1982","journal-title":"Am. J. Gastroenterol."}],"container-title":["Histopathology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fhis.13824","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/his.13824","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1111\/his.13824","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/his.13824","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,9,10]],"date-time":"2023-09-10T18:28:47Z","timestamp":1694370527000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/his.13824"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,3,20]]},"references-count":6,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2019,5]]}},"alternative-id":["10.1111\/his.13824"],"URL":"https:\/\/doi.org\/10.1111\/his.13824","archive":["Portico"],"relation":{},"ISSN":["0309-0167","1365-2559"],"issn-type":[{"value":"0309-0167","type":"print"},{"value":"1365-2559","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,3,20]]},"assertion":[{"value":"2018-10-26","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2018-12-14","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2019-03-20","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}