{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T17:11:49Z","timestamp":1781629909796,"version":"3.54.5"},"reference-count":8,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T00:00:00Z","timestamp":1768348800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":26,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Pulm Med"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Primary mesenchymal tumors of the mediastinum are extremely rare and often pose considerable diagnostic challenges owing to their histological diversity and anatomical location. We report the case of a 51-year-old man with a 45 pack-year smoking history who was referred for evaluation of a mediastinal mass initially detected by chest radiography. Thoracic computed tomography (CT) and positron emission tomography-CT revealed a 3\u2009\u00d7\u20093\u00a0cm lesion extending from the right upper and lower paratracheal regions into the right upper lobe parenchyma, demonstrating intense FDG uptake. Fiber-optic bronchoscopy revealed no endobronchial lesions. A CT-guided transthoracic needle biopsy was non-diagnostic. Subsequently, linear endobronchial ultrasound (L-EBUS) was performed, and a transbronchial needle biopsy sample was obtained for histopathological examination. Histopathological examination revealed an undifferentiated malignant mesenchymal tumor, positive for vimentin, with a Ki-67 proliferation index of approximately 30%. Despite an extensive immunohistochemical panel, no specific line of differentiation was established. Following the diagnosis, the patient was discussed at a multidisciplinary tumor board and subsequently referred to medical oncology for systemic treatment. This case highlights the role of L-EBUS in obtaining adequate tissue for the diagnosis of a rare malignant mesenchymal mediastinal tumor, particularly after inconclusive conventional biopsy attempts. Accurate diagnosis of such rare tumors requires a multidisciplinary strategy incorporating imaging, histopathology, and immunohistochemistry to guide appropriate treatment planning and prognostication of the disease.<\/jats:p>","DOI":"10.1186\/s12890-026-04103-7","type":"journal-article","created":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T13:53:44Z","timestamp":1768398824000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A rare primary mediastinal mesenchymal tumor diagnosed by endobronchial ultrasound (EBUS)"],"prefix":"10.1186","volume":"26","author":[{"given":"Serap","family":"Argun Baris","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huseyin","family":"Kaya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gozde","family":"Selvi Guldiken","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gozde","family":"Oksuzler Kizilbay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cigdem","family":"Vural","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilknur","family":"Basyigit","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hasim","family":"Boyaci","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,1,14]]},"reference":[{"key":"4103_CR1","doi-asserted-by":"publisher","first-page":"487","DOI":"10.1007\/s00428-015-1830-8","volume":"467","author":"MA den Bakker","year":"2015","unstructured":"den Bakker MA, Marx A, Mukai K, Str\u00f6bel P. Mesenchymal tumours of the mediastinum\u2014part I. Virchows Arch. 2015;467:487\u2013500. https:\/\/doi.org\/10.1007\/s00428-015-1830-8.","journal-title":"Virchows Arch"},{"issue":"5","key":"4103_CR2","doi-asserted-by":"publisher","first-page":"449","DOI":"10.1007\/s00292-016-0190-8","volume":"37","author":"RJ Rieker","year":"2016","unstructured":"Rieker RJ, Marx A, Agaimy A, Str\u00f6bel P. Mesenchymale tumoren des mediastinums. Pathologe. 2016;37(5):449\u201356. https:\/\/doi.org\/10.1007\/s00292-016-0190-8.","journal-title":"Pathologe"},{"key":"4103_CR3","doi-asserted-by":"publisher","first-page":"152018","DOI":"10.1016\/j.anndiagpath.2022.152018","volume":"60","author":"D Suster","year":"2022","unstructured":"Suster D. Spindle cell tumors of the mediastinum. Ann Diagn Pathol. 2022;60:152018. https:\/\/doi.org\/10.1016\/j.anndiagpath.2022.152018.","journal-title":"Ann Diagn Pathol"},{"issue":"2","key":"4103_CR4","doi-asserted-by":"publisher","first-page":"200","DOI":"10.1016\/j.jtho.2021.10.010","volume":"17","author":"A Marx","year":"2022","unstructured":"Marx A, Chan JKC, Chalabreysse L, et al. The 2021 WHO classification of tumors of the thymus and mediastinum: what is new in thymic Epithelial, germ Cell, and mesenchymal tumors? J Thorac Oncol. 2022;17(2):200\u201313. https:\/\/doi.org\/10.1016\/j.jtho.2021.10.010.","journal-title":"J Thorac Oncol"},{"issue":"5","key":"4103_CR5","doi-asserted-by":"publisher","first-page":"351","DOI":"10.1097\/PAP.0000000000000306","volume":"28","author":"JH Choi","year":"2021","unstructured":"Choi JH, Ro JY. Mesenchymal tumors of the mediastinum: an update on diagnostic approach. Adv Anat Pathol. 2021;28(5):351\u201381. https:\/\/doi.org\/10.1097\/PAP.0000000000000306.","journal-title":"Adv Anat Pathol"},{"key":"4103_CR6","doi-asserted-by":"publisher","first-page":"501","DOI":"10.1007\/s00428-015-1832-6","volume":"467","author":"MA den Bakker","year":"2015","unstructured":"den Bakker MA, Marx A, Mukai K, Str\u00f6bel P. Mesenchymal tumours of the mediastinum\u2014part II. Virchows Arch. 2015;467:501\u201317. https:\/\/doi.org\/10.1007\/s00428-015-1832-6.","journal-title":"Virchows Arch"},{"key":"4103_CR7","doi-asserted-by":"publisher","first-page":"549","DOI":"10.12659\/AJCR.903680","volume":"18","author":"AJ Webb","year":"2017","unstructured":"Webb AJ, Yassin AS, Saeed A, Yadav H, Utz JP. Mediastinal solitary fibrous tumor diagnosed by endobronchial Ultrasound-Directed biopsy. Am J Case Rep. 2017;18:549\u201352. https:\/\/doi.org\/10.12659\/AJCR.903680.","journal-title":"Am J Case Rep"},{"issue":"3","key":"4103_CR8","doi-asserted-by":"publisher","first-page":"331","DOI":"10.1510\/icvts.2010.244459","volume":"11","author":"F Chen","year":"2010","unstructured":"Chen F, Yoshizawa A, Okubo K, Date H. Characteristic endobronchial ultrasound image of hemangiopericytoma\/solitary fibrous tumor. Interact Cardiovasc Thorac Surg. 2010;11(3):331\u20132. https:\/\/doi.org\/10.1510\/icvts.2010.244459.","journal-title":"Interact Cardiovasc Thorac Surg"}],"container-title":["BMC Pulmonary Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s12890-026-04103-7","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12890-026-04103-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12890-026-04103-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T16:45:10Z","timestamp":1781628310000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1186\/s12890-026-04103-7"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,14]]},"references-count":8,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["4103"],"URL":"https:\/\/doi.org\/10.1186\/s12890-026-04103-7","relation":{},"ISSN":["1471-2466"],"issn-type":[{"value":"1471-2466","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,14]]},"assertion":[{"value":"6 October 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"1 January 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 January 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable (single patient case report; patient consent obtained).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Written informed consent was obtained from the patient for publication of this case report and any accompanying images.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"61"}}