{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T05:25:14Z","timestamp":1762147514731,"version":"build-2065373602"},"reference-count":9,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T00:00:00Z","timestamp":1762128000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:p>A 74-year-old man presented with abdominal bloating and was diagnosed with unresectable advanced adenocarcinoma from a Meckel\u2019s diverticulum with distant lung metastases and peritoneal dissemination. On immunohistochemical analysis, the tumor was positive for MUC5AC and MUC6 and negative for MUC2 and CDX2, indicating a gastric phenotype. Histological examination of the adjacent non-cancerous tissues confirmed the presence of ectopic gastric epithelium, resulting in a final diagnosis of adenocarcinoma arising from ectopic gastric tissue within a Meckel\u2019s diverticulum. Biomarker profiling demonstrated Claudin 18.2 (CLDN18.2) positivity, HER2 negativity, and mismatch repair proficiency. Treatment was started with zolbetuximab plus 5-fluorouracil\/leucovorin\/oxaliplatin (FOLFOX), which is typically used for CLDN18.2-positive gastric cancer, resulting in a partial response. This is the first case of zolbetuximab-based therapy applied to adenocarcinoma from a Meckel\u2019s diverticulum with a gastric phenotype due to a biomarker profile of gastric cancer. This case highlights the importance of identifying both the biomarker profile and tissue of origin of the tumor.<\/jats:p>","DOI":"10.3389\/fonc.2025.1700562","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T05:21:40Z","timestamp":1762147300000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: A case of zolbetuximab-based chemotherapy for Claudin 18.2-positive gastric phenotype adenocarcinoma arising in Meckel\u2019s diverticulum"],"prefix":"10.3389","volume":"15","author":[{"given":"Kohei","family":"Nagata","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takayuki","family":"Ando","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryusuke","family":"Hanafusa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Iori","family":"Motoo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuko","family":"Ueda","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shinya","family":"Kajiura","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yusuke","family":"Takashima","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kenji","family":"Watanabe","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kohji","family":"Takagi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kenichi","family":"Hirabayashi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ichiro","family":"Yasuda","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,11,3]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1177\/014107680609901011","article-title":"Meckel\u2019s Diverticulum: a systematic review","volume":"99","author":"Sagar","year":"2006","journal-title":"J R Soc Med"},{"key":"B2","doi-asserted-by":"publisher","first-page":"75","DOI":"10.1016\/j.amsu.2019.05.017","article-title":"Malignant neoplasms of Meckel\u2019s diverticulum; an evidence based review","volume":"43","author":"Kabir","year":"2019","journal-title":"Ann Med Surg"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1097\/SLA.0b013e3181ef488d","article-title":"Meckel\u2019s diverticulum-a high-risk region for Malignancy in the ileum. Insights from a population-based epidemiological study and implications in surgical management","volume":"253","author":"Thirunavukarasu","year":"2011","journal-title":"Ann Surg"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1093\/jjco\/hyq","article-title":"Successful treatment of gastric adenocarcinoma in a meckel\u2019s diverticulum with pemetrexed plus carboplatin","volume":"40","author":"Muto","year":"2010","journal-title":"Jpn J Clin Oncol"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.4103\/jcrt.JCRT_124_17","article-title":"Adenocarcinoma located at a Meckel\u2019s Diverticulum: a case report and literature review","volume":"13","author":"Yang","year":"2017","journal-title":"J Cancer Res Ther"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijscr.2019.07.005","article-title":"Peritoneal metastases from Malignant degeneration of ectopic gastric epithelium in Meckel\u2019s diverticulum: a case report","volume":"61","author":"El Bahesh","year":"2019","journal-title":"Int J Surg Case Rep"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1038\/s41591-023-02465-7","article-title":"Zolbetuximab plus CAPOX in CLDN18.2-positive gastric or gastroesophageal junction adenocarcinoma: the randomized, phase 3 GLOW trial","volume":"29","author":"Shah","year":"2023","journal-title":"Nat Med"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(23)00620-7","article-title":"Zolbetuximab plus mFOLFOX6 in patients with CLDN18.2-positive, HER2-negative, untreated, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma (SPOTLIGHT): a multicentre, randomised, double-blind, phase 3 trial","volume":"401","author":"Shitara","year":"2023","journal-title":"Lancet"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.3390\/nu17010188","article-title":"Progress and challenges in integrating nutritional care into oncology practice: results from a national survey on behalf of the nutriOnc research group","volume":"17","author":"De Felice","year":"2025","journal-title":"Nutrients"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2025.1700562\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T05:21:41Z","timestamp":1762147301000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2025.1700562\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,3]]},"references-count":9,"alternative-id":["10.3389\/fonc.2025.1700562"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2025.1700562","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,3]]},"article-number":"1700562"}}