{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T05:23:34Z","timestamp":1787203414592,"version":"build-2736575974"},"reference-count":8,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T00:00:00Z","timestamp":1787011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002649","name":"Yeungnam University","doi-asserted-by":"publisher","award":["224A580015"],"award-info":[{"award-number":["224A580015"]}],"id":[{"id":"10.13039\/501100002649","id-type":"DOI","asserted-by":"publisher"}]},{"award":["224A580015"],"award-info":[{"award-number":["224A580015"]}],"id":[{"id":"https:\/\/ror.org\/05yc6p159","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Central nervous system histiocytic sarcoma is exceedingly uncommon, particularly with intramedullary spinal cord involvement. We describe a 27-year-old man presenting with motor weakness and radiating pain. MRI revealed a homogeneously enhancing intramedullary mass at the C2\u20133 level with diffuse leptomeningeal dissemination, raising suspicion for a disseminated neoplastic process. Histopathology demonstrated pleomorphic large histiocyte-like cells with strong CD163, CD68, and lysozyme expression, confirming histiocytic sarcoma. Targeted next-generation sequencing detected a TP53 hotspot mutation (p.Arg273His), classified as a Tier II variant according to the joint AMP\/ASCO\/CAP guidelines, while additional variants were of uncertain clinical significance. This case highlights the rare intramedullary presentation of histiocytic sarcoma with leptomeningeal dissemination and emphasizes the importance of radiologic\u2013pathologic correlation for accurate diagnosis.<\/jats:p>","DOI":"10.3390\/diagnostics16162623","type":"journal-article","created":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T17:37:52Z","timestamp":1787074672000},"page":"2623","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Primary Intramedullary Histiocytic Sarcoma with Leptomeningeal Dissemination: Imaging, Pathologic, and Molecular Correlation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2128-3524","authenticated-orcid":false,"given":"Su Hong","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Radiology, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hee Jung","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Pathology, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8350-3038","authenticated-orcid":false,"given":"Mi Jin","family":"Gu","sequence":"additional","affiliation":[{"name":"Department of Pathology, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2871-3198","authenticated-orcid":false,"given":"Wook Tae","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1016\/j.jmoldx.2016.10.002","article-title":"Standards and guidelines for the interpretation and reporting of sequence variants in cancer: A joint consensus recommendation of the Association for Molecular Pathology, American Society of Clinical Oncology, and College of American Pathologists","volume":"19","author":"Li","year":"2017","journal-title":"J. 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Pathol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e1263","DOI":"10.1002\/onco.13801","article-title":"Histiocytic and dendritic cell sarcomas of hematopoietic origin share targetable genomic alterations","volume":"26","author":"Massoth","year":"2021","journal-title":"Oncologist"}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/16\/2623\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T04:27:36Z","timestamp":1787200056000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/16\/2623"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,18]]},"references-count":8,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["diagnostics16162623"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16162623","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,18]]}}}