{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T14:03:59Z","timestamp":1784642639523,"version":"3.55.0"},"reference-count":24,"publisher":"BMJ","issue":"7","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"unspecified","delay-in-days":20,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,6,25]]},"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:p>A female in her early 80s presented with chronic anal fissures which were unresponsive to conservative therapies. Examination was concerning for possible perianal Crohn\u2019s disease, but subsequent colonoscopy and biopsies revealed Langerhans cell histiocytosis (LCH) involving the colon and anus, diagnosed per 2022 WHO Classification of Haematolymphoid Tumours criteria and confirmed by BRAF V600E mutation. Systemic staging identified two unrelated malignancies of the breast and kidney. The patient was treated with cladribine as systemic chemotherapy, resulting in complete remission of LCH symptoms and lesions.<\/jats:p>\n                  <jats:p>This case illustrates key diagnostic and therapeutic considerations for clinicians: LCH can mimic inflammatory bowel disease and should be included in the differential for atypical or refractory perianal disease, especially in older adults. Histological confirmation and molecular profiling are essential for accurate diagnosis and treatment planning. Additionally, cladribine is a well-tolerated and effective option for adult LCH with gastrointestinal tract involvement. Early recognition and systemic staging are critical to guide therapy and identify potential coexisting malignancies.<\/jats:p>","DOI":"10.1136\/bcr-2025-269806","type":"journal-article","created":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T13:35:30Z","timestamp":1784640930000},"page":"e269806","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Langerhans cell histiocytosis in the adult lower gastrointestinal tract"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-6908-3899","authenticated-orcid":false,"given":"Xiaozhi","family":"Yang","sequence":"first","affiliation":[{"name":"Schulich School of Medicine & Dentistry Windsor Program, Western University, Windsor, Ontario, Canada"},{"name":"Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Alomari","sequence":"additional","affiliation":[{"name":"Department of Pathology, Windsor Regional Hospital, Windsor, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Raskin","sequence":"additional","affiliation":[{"name":"Department of General Surgery, Windsor Regional Hospital Metropolitan Campus, Windsor, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"key":"2026072106351436000_19.7.e269806.1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMra1607548"},{"key":"2026072106351436000_19.7.e269806.2","doi-asserted-by":"crossref","first-page":"2601","DOI":"10.1182\/blood.2021014343","article-title":"International expert consensus recommendations for the diagnosis and treatment of Langerhans cell histiocytosis in adults","volume":"139","author":"Goyal","year":"2022","journal-title":"Blood"},{"key":"2026072106351436000_19.7.e269806.3","doi-asserted-by":"crossref","first-page":"1658","DOI":"10.1097\/PAS.0000000000001562","article-title":"Langerhans Cell Histiocytosis Associated With Renal Cell Carcinoma Is a Neoplastic Process: Clinicopathologic and Molecular Study of 7 Cases","volume":"44","author":"Agaimy","year":"2020","journal-title":"Am J Surg Pathol"},{"key":"2026072106351436000_19.7.e269806.4","doi-asserted-by":"crossref","first-page":"6568","DOI":"10.1182\/bloodadvances.2023010706","article-title":"Long-term outcomes among adults with Langerhans cell histiocytosis","volume":"7","author":"Goyal","year":"2023","journal-title":"Blood Adv"},{"key":"2026072106351436000_19.7.e269806.5","doi-asserted-by":"crossref","first-page":"4459","DOI":"10.1007\/s00277-024-06034-x","article-title":"Manifestations and outcomes of digestive tract involvement in adult Langerhans cell histiocytosis","volume":"103","author":"Shang","year":"2024","journal-title":"Ann Hematol"},{"key":"2026072106351436000_19.7.e269806.6","doi-asserted-by":"crossref","first-page":"1945","DOI":"10.1007\/s10147-020-01739-1","article-title":"Gastrointestinal lesion in adult-onset Langerhans cell histiocytosis","volume":"25","author":"Matsubara","year":"2020","journal-title":"Int J Clin Oncol"},{"key":"2026072106351436000_19.7.e269806.7","doi-asserted-by":"crossref","DOI":"10.1097\/MD.0000000000040950","article-title":"Isolated Langerhans cell histiocytosis of the stomach in adults: An analysis of clinicopathologic characteristics and molecular genetics","volume":"103","author":"Wu","year":"2024","journal-title":"Medicine (Baltimore)"},{"key":"2026072106351436000_19.7.e269806.8","doi-asserted-by":"publisher","DOI":"10.1097\/PAS.0b013e31820654e4"},{"key":"2026072106351436000_19.7.e269806.9","doi-asserted-by":"crossref","first-page":"1410","DOI":"10.3748\/wjg.v18.i12.1410","article-title":"A rare case of langerhans cell histiocytosis of the gastrointestinal tract","volume":"18","author":"Shankar","year":"2012","journal-title":"World J Gastroenterol"},{"key":"2026072106351436000_19.7.e269806.10","doi-asserted-by":"crossref","first-page":"1501","DOI":"10.1007\/s00384-018-3066-y","article-title":"Langerhans cell histiocytosis presenting as Crohn\u2019s disease: a case report","volume":"33","author":"Therrien","year":"2018","journal-title":"Int J Colorectal Dis"},{"key":"2026072106351436000_19.7.e269806.11","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM199407213310303"},{"key":"2026072106351436000_19.7.e269806.12","first-page":"8018","article-title":"Up-regulation of Tim-3 is associated with poor prognosis of patients with colon cancer","volume":"8","author":"Zhou","year":"2015","journal-title":"Int J Clin Exp Pathol"},{"key":"2026072106351436000_19.7.e269806.13","doi-asserted-by":"publisher","DOI":"10.5858\/arpa.2014-0290-CC"},{"key":"2026072106351436000_19.7.e269806.14","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1007\/s00277-004-0974-4","article-title":"The place of cladribine in the treatment of chronic lymphocytic leukemia: a 10-year experience in Poland","volume":"84","author":"Robak","year":"2005","journal-title":"Ann Hematol"},{"key":"2026072106351436000_19.7.e269806.15","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1002\/ajh.25371","article-title":"Systemic mastocytosis in adults: 2019 update on diagnosis, risk stratification and management","volume":"94","author":"Pardanani","year":"2019","journal-title":"Am J Hematol"},{"key":"2026072106351436000_19.7.e269806.16","doi-asserted-by":"crossref","first-page":"4125","DOI":"10.1182\/blood.V93.12.4125","article-title":"Cladribine activity in adult langerhans-cell histiocytosis","volume":"93","author":"Saven","year":"1999","journal-title":"Blood"},{"key":"2026072106351436000_19.7.e269806.17","doi-asserted-by":"crossref","first-page":"994","DOI":"10.3109\/0284186X.2012.716164","article-title":"Cladribine (2-chlorodeoxyadenosine) in frontline chemotherapy for adult Langerhans cell histiocytosis: A single-center study of seven cases","volume":"52","author":"Adam","year":"2013","journal-title":"Acta Oncol (Madr)"},{"key":"2026072106351436000_19.7.e269806.18","doi-asserted-by":"crossref","first-page":"869","DOI":"10.1111\/bjh.16449","article-title":"Long-term efficacy and safety of 2CdA (cladribine) in extra-pulmonary adult-onset Langerhans cell histiocytosis: analysis of 23 cases from the French Histiocytosis Group and systematic literature review","volume":"189","author":"N\u00e9el","year":"2020","journal-title":"Br J Haematol"},{"key":"2026072106351436000_19.7.e269806.19","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1002\/ajh.26412","article-title":"Treatment outcomes and prognostic factors of patients with adult Langerhans cell histiocytosis","volume":"97","author":"Cao","year":"2022","journal-title":"American J Hematol"},{"key":"2026072106351436000_19.7.e269806.20","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.19.00456"},{"key":"2026072106351436000_19.7.e269806.21","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2015.65.9508"},{"key":"2026072106351436000_19.7.e269806.22","doi-asserted-by":"publisher","DOI":"10.1016\/S0959-8049(03)00672-5"},{"key":"2026072106351436000_19.7.e269806.23","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2010-02-246140"},{"key":"2026072106351436000_19.7.e269806.24","doi-asserted-by":"publisher","DOI":"10.1200\/jco.18.01160"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-269806","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T13:35:32Z","timestamp":1784640932000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-269806"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7]]},"references-count":24,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,7,21]]},"published-print":{"date-parts":[[2026,7]]}},"alternative-id":["10.1136\/bcr-2025-269806"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-269806","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7]]}}}