{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T07:28:01Z","timestamp":1774510081656,"version":"3.50.1"},"reference-count":18,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:00:00Z","timestamp":1774483200000},"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>SS18::POU5F1-fused sarcoma is an exceedingly rare malignant tumor, with only isolated case reports documented to date. We present the first reported case of SS18::POU5F1 fusion sarcoma occurring in the left submandibular gland of a middle-aged male patient. The tumor exhibited multiphasic differentiation, including epithelioid cells and undifferentiated round cell components, with focal evidence of neural differentiation and Flexner\u2013Wintersteiner rosettes. It was characterized by the presence of a SS18::POU5F1 gene fusion. We provide a detailed description of the clinical features, histomorphology, immunophenotype, molecular characteristics, treatment, and prognosis of this case, discuss its differential diagnosis and potential pathogenesis, and include a comprehensive review of the relevant literature.<\/jats:p>","DOI":"10.3389\/fonc.2026.1768229","type":"journal-article","created":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T05:19:07Z","timestamp":1774502347000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: SS18::POU5F1-fused sarcoma with Flexner-Wintersteiner rosettes: a clinicopathological analysis of a rare tumor in the submandibular gland"],"prefix":"10.3389","volume":"16","author":[{"given":"Zhaorong","family":"Niu","sequence":"first","affiliation":[{"name":"Pathology Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guixiang","family":"Xiao","sequence":"additional","affiliation":[{"name":"Pathology Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yu","family":"Guo","sequence":"additional","affiliation":[{"name":"Department of Pathology, First People\u2019s Hospital of Yibin City","place":["Sichuan, Yibin, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qin","family":"Xia","sequence":"additional","affiliation":[{"name":"Pathology Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology","place":["Wuhan, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Fan","sequence":"additional","affiliation":[{"name":"Pathology Department, Union Hospital, Tongji Medical College, Huazhong University of 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