{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T05:30:58Z","timestamp":1770442258893,"version":"3.49.0"},"reference-count":22,"publisher":"BMJ","issue":"8","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2025,7,23]]},"published-print":{"date-parts":[[2025,8]]},"abstract":"<jats:p>Due to abdominal discomfort and a positive first-degree family history of bowel cancer, a woman (in her late 50s) underwent colonoscopy. A large (35 mm) colorectal adenoma of the ascending colon was removed by endoscopic mucosal resection. On histopathology, the adenoma showed low and focal high-grade dysplasia with nests of tumour cells with squamous differentiation and pseudoinvasion.<\/jats:p>\n                  <jats:p>The polyp was fully excised endoscopically; however, it needed complex polyps MDT discussion for an agreed follow up plan.<\/jats:p>\n                  <jats:p>Squamous morules, within colorectal adenomas, are rare benign lesions with low proliferative activity. Their incidence is reported to be around 0.4%. They can mimic malignant features and may be incorrectly diagnosed as invasive adenocarcinoma. While rare, they may be indicative of high risk of recurrence adenoma. We present this case as a satisfactory model of the advantages of precise diagnosis, clear explanation and discussion between experts, leading to an accurate follow-up plan.<\/jats:p>","DOI":"10.1136\/bcr-2025-265833","type":"journal-article","created":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T04:10:22Z","timestamp":1755144622000},"page":"e265833","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Pseudoinvasive squamous morula in a large colorectal polyp with low and high grade dysplasia"],"prefix":"10.1136","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2618-1625","authenticated-orcid":false,"given":"Gabriella","family":"Massarenti","sequence":"first","affiliation":[{"name":"Internal Medicine, IRCCS University Hospital of Bologna Sant Orsola Polyclinic, Bologna, Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marco R","family":"Novelli","sequence":"additional","affiliation":[{"name":"Pathology, University College Hospital, London, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2234-8262","authenticated-orcid":false,"given":"Cinzia","family":"Papadia","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Queen Mary University of London, London, UK"},{"name":"Whipps Cross University Hospital, London, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2025,8,13]]},"reference":[{"key":"2025081321101588000_18.8.e265833.1","doi-asserted-by":"publisher","DOI":"10.3748\/wjg.v23.i20.3632"},{"key":"2025081321101588000_18.8.e265833.2","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1111\/his.14263","article-title":"Incidental morphological findings in colorectal adenomas","volume":"78","author":"Dabir","year":"2021","journal-title":"Histopathology"},{"key":"2025081321101588000_18.8.e265833.3","doi-asserted-by":"publisher","DOI":"10.1159\/000089421"},{"key":"2025081321101588000_18.8.e265833.4","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1016\/j.humpath.2017.08.019","article-title":"Squamoid morules in the pseudoinvasive foci of colonic polyp morphologically mimic invasive carcinoma","volume":"68","author":"Lee","year":"2017","journal-title":"Hum Pathol"},{"key":"2025081321101588000_18.8.e265833.5","doi-asserted-by":"crossref","unstructured":"Salaria SN . 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