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His symptoms persisted despite discontinuation of Braftovi-Mektovi (BRAF\u2013MEK) therapy and required escalation of corticosteroid therapy and budesonide initiation. This case highlights the diagnostic challenges of differentiating ICI-mediated colitis from adverse events of targeted therapy and underscores the importance of endoscopic and histological confirmation in guiding treatment.<\/jats:p>","DOI":"10.1136\/bcr-2025-270566","type":"journal-article","created":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T12:55:22Z","timestamp":1779195322000},"page":"e270566","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Immune checkpoint inhibitor-associated lymphocytic colitis in a patient with metastatic melanoma"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8853-8408","authenticated-orcid":false,"given":"Reem","family":"Matar","sequence":"first","affiliation":[{"name":"Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Khalid","family":"Abu Zeinah","sequence":"additional","affiliation":[{"name":"Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tanish","family":"Modi","sequence":"additional","affiliation":[{"name":"Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allison","family":"Ducharme-Smith","sequence":"additional","affiliation":[{"name":"Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,5,19]]},"reference":[{"key":"2026051905551104000_19.5.e270566.1","doi-asserted-by":"crossref","DOI":"10.1186\/s40425-018-0346-6","article-title":"Immune-checkpoint inhibitor-induced diarrhea and colitis in patients with advanced malignancies: retrospective review at MD Anderson","volume":"6","author":"Wang","year":"2018","journal-title":"J Immunother Cancer"},{"key":"2026051905551104000_19.5.e270566.2","article-title":"Management of immune checkpoint inhibitor-induced colitis: a comprehensive review","volume":"11","author":"Collins","year":"2020","journal-title":"Clin Transl Gastroenterol"},{"key":"2026051905551104000_19.5.e270566.3","article-title":"Immune checkpoint inhibitor-induced diarrhea and colitis: an overview","volume":"32","author":"Zoghbi","year":"2024","journal-title":"Support Care Cancer"},{"key":"2026051905551104000_19.5.e270566.4","doi-asserted-by":"publisher","DOI":"10.1053\/j.gastro.2020.08.063"},{"key":"2026051905551104000_19.5.e270566.5","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2005.04.5716"},{"key":"2026051905551104000_19.5.e270566.6","doi-asserted-by":"publisher","DOI":"10.1097\/PAS.0000000000000829"},{"key":"2026051905551104000_19.5.e270566.7","doi-asserted-by":"crossref","DOI":"10.1093\/crocol\/otac008","article-title":"Clinical Course and Impact of Immune Checkpoint Inhibitor Colitis Resembling Microscopic Colitis","volume":"4","author":"Fredrick","year":"2022","journal-title":"Crohn\u2019s & Colitis 360"},{"key":"2026051905551104000_19.5.e270566.8","doi-asserted-by":"crossref","unstructured":"Garutti M , Bergnach M , Polesel J , et al . n.d. 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