{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T05:13:39Z","timestamp":1783660419564,"version":"3.55.0"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"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:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Myeloid sarcoma (MS) is a rare extramedullary tumor of immature myeloid cells. Intracranial MS occurring as an extramedullary relapse without concurrent systemic acute myeloid leukemia (AML), is exceptionally rare and poses a considerable diagnostic challenge due to its non-specific clinical and radiological features, often mimicking more common intracranial neoplasms like meningioma.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case presentation<\/jats:title>\n                    <jats:p>We report a case of isolated intracranial MS in a 61-year-old female with a prior history of FLT3-ITD mutated AML (M2), who had been in sustained complete hematologic remission for four years. She presented with a two-week history of diminished responsiveness and apathy. Cranial MRI revealed a well-defined, homogenously enhancing left frontal mass with a dural tail sign and significant peritumoral edema, initially suggestive of a meningioma. However, diffusion-weighted imaging (DWI) demonstrated restricted diffusion. The tumor was resected. Histopathological examination revealed diffuse sheets of immature myeloid cells. Immunohistochemistry was positive for CD117, CD34, and CD68, with weak MPO expression, confirming the diagnosis of MS. Post-operatively, the patient was referred for systemic chemotherapy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This case illustrates that intracranial MS can be a form of extramedullary relapse in AML patients even during long-term remission and can closely mimic a meningioma radiologically. Key diagnostic clues include a prior history of AML and radiographic features such as restricted diffusion on DWI and prominent peritumoral edema. However, these findings are non-specific, and a definitive diagnosis relies on histopathological and immunohistochemical analysis. The management of MS should be based on systemic AML therapy principles rather than surgery alone. This report highlights the necessity of considering MS in the differential diagnosis of new intracranial masses in patients with a history of AML to ensure timely and appropriate treatment.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fonc.2026.1769002","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T04:24:12Z","timestamp":1783657452000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Intracranial extramedullary relapse of acute myeloid leukemia presenting as myeloid sarcoma mimicking meningioma: a case report and literature review"],"prefix":"10.3389","volume":"16","author":[{"given":"Yuan","family":"Cao","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, General Hospital of Northern Theatre Command","place":["Shenyang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Cao","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, General Hospital of Northern Theatre Command","place":["Shenyang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3390\/jcm4051102","article-title":"Intracranial CNS manifestations of myeloid sarcoma in patients with acute myeloid leukemia: Review of the literature and three case reports from the author's institution","volume":"4","author":"Cervantes","year":"2015","journal-title":"J Clin Med"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1038\/s41375-022-01613-1","article-title":"The 5th edition of the World Health Organization classification of haematolymphoid tumours: Myeloid and histiocytic\/dendritic neoplasms","volume":"36","author":"Khoury","year":"2022","journal-title":"Leukemia"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1200\/jco.1995.13.7.1800","article-title":"Extramedullary myeloid cell tumors in acute nonlymphocytic leukemia: A clinical review","volume":"13","author":"Byrd","year":"1995","journal-title":"J Clin Oncol"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1080\/10428190600967196","article-title":"Granulocytic sarcoma: 32 cases and review of the literature","volume":"47","author":"Paydas","year":"2006","journal-title":"Leukemia Lymphoma"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-16483-5_57","article-title":"Acute lymphoblastic leukemia","volume":"350","author":"Pui","year":"2004","journal-title":"N Engl J Med"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1002\/1097-0142(19810915)48:6<1426::aid-cncr2820480626>3.0.co;2-g","article-title":"Granulocytic sarcoma: A clinicopathologic study of 61 biopsied cases","volume":"48","author":"Neiman","year":"1981","journal-title":"Cancer"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1038\/sj.leu.2404491","article-title":"Myeloid sarcoma: Clinico-pathologic, phenotypic and cytogenetic analysis of 92 adult patients","volume":"21","author":"Pileri","year":"2007","journal-title":"Leukemia"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1038\/nm1489","article-title":"Requirement for CD44 in homing and engraftment of BCR-ABL-expressing leukemic stem cells","volume":"12","author":"Krause","year":"2006","journal-title":"Nat Med"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1016\/j.leukres.2004.01.006","article-title":"Extramedullary infiltrates of AML are associated with CD56 expression, 11q23 abnormalities and inferior clinical outcome","volume":"28","author":"Chang","year":"2004","journal-title":"Leukemia Res"},{"key":"B10","doi-asserted-by":"publisher","first-page":"698","DOI":"10.1148\/radiology.190.3.8115614","article-title":"Granulocytic sarcoma in childhood leukemia: Imaging features","volume":"190","author":"Pui","year":"1994","journal-title":"Radiology"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1158\/0008-5472.can-03-3693","article-title":"CXCR4 regulates migration and development of human acute myelogenous leukemia stem cells in transplanted NOD\/SCID mice","volume":"64","author":"Tavor","year":"2004","journal-title":"Cancer Res"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2008-04-148643","article-title":"Role of leukemia cell invadosome in extramedullary infiltration","volume":"114","author":"Stefanidakis","year":"2009","journal-title":"Blood"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2011-04-347229","article-title":"How I treat extramedullary acute myeloid leukemia","volume":"118","author":"Bakst","year":"2011","journal-title":"Blood"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1056\/nejmoa041974","article-title":"Cytoplasmic nucleophosmin in acute myelogenous leukemia with a normal karyotype","volume":"352","author":"Falini","year":"2005","journal-title":"N Engl J Med"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2016-08-733196","article-title":"Diagnosis and management of AML in adults: 2017 ELN recommendations from an international expert panel","volume":"129","author":"D\u00f6hner","year":"2017","journal-title":"Blood"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1038\/nrc1169","article-title":"The role of FLT3 in haematopoietic Malignancies","volume":"3","author":"Stirewalt","year":"2003","journal-title":"Nat Rev Cancer"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1016\/j.clml.2017.02.027","article-title":"Myeloid sarcoma: Presentation, diagnosis, and treatment","volume":"17","author":"Almond","year":"2017","journal-title":"Clin Lymphoma Myeloma Leukemia"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1002\/cncr.10399","article-title":"Comparison in treatments of nonleukemic granulocytic sarcoma: Report of two cases and a review of 72 cases in the literature","volume":"94","author":"Yamauchi","year":"2002","journal-title":"Cancer"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1182\/blood.v42.5.721.721","article-title":"Chloroma and other myeloblastic tumors","volume":"42","author":"Muss","year":"1973","journal-title":"Blood"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1159\/000253592","article-title":"Prognostic factors of treatment outcomes in patients with granulocytic sarcoma","volume":"122","author":"Lan","year":"2009","journal-title":"Acta Haematologica"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-18832-9_20","article-title":"Granulocytic sarcoma (chloroma): Imaging findings in adults and children","volume":"178","author":"Guermazi","year":"2002","journal-title":"AJR Am J Roentgenology"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1097\/rct.0000000000000337","article-title":"Qualitative assessment of diffusion weighted imaging and susceptibility weighted imaging of myeloid sarcoma involving the brain","volume":"40","author":"Chaudhry","year":"2016","journal-title":"J Comput Assisted Tomogr"},{"key":"B23","doi-asserted-by":"publisher","first-page":"1150","DOI":"10.1186\/s12885-019-6357-y","article-title":"Clinical and imaging features of myeloid sarcoma: A German multicenter study","volume":"19","author":"Meyer","year":"2019","journal-title":"BMC Cancer"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.3324\/haematol.2011.045047","article-title":"18F-FDG-PET\/CT for detection of extramedullary acute myeloid leukemia","volume":"96","author":"St\u00f6lzel","year":"2011","journal-title":"Haematologica"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1002\/1097-0142(197304)31:4<948::aid-cncr2820310428>3.0.co;2-n","article-title":"Autopsy study of granulocytic sarcoma (chloroma) in patients with myelogenous leukemia, Hiroshima-Nagasaki 1949-1969","volume":"31","author":"Liu","year":"1973","journal-title":"Cancer"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.4103\/0973-1482.220418","article-title":"Myeloid sarcoma: A clinicopathological study with emphasis on diagnostic difficulties","volume":"13","author":"Kudva","year":"2017","journal-title":"J Cancer Res Ther"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1056\/nejmoa1516192","article-title":"Genomic classification and prognosis in acute myeloid leukemia","volume":"374","author":"Papaemmanuil","year":"2016","journal-title":"N Engl J Med"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-553x.2011.01361.x","article-title":"State of the art in myeloid sarcoma","volume":"33","author":"Klco","year":"2011","journal-title":"Int J Labor Hematol"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1309\/AJCP1ZA7HYZKAZHS","article-title":"Myeloid sarcoma: Extramedullary manifestation of myeloid disorders","volume":"132","author":"Campidelli","year":"2009","journal-title":"Am J Clin Pathol"},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1097\/00000478-200012000-00010","article-title":"Immunohistochemical detection of FLI-1 protein expression: A study of 132 round cell tumors with emphasis on CD99-positive mimics of Ewing's sarcoma\/primitive neuroectodermal tumor","volume":"24","author":"Folpe","year":"2000","journal-title":"Am J Surg Pathol"},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1200\/jco.20.03060","article-title":"Genomic classification and clinical outcome in rhabdomyosarcoma: A report from an international consortium","volume":"39","author":"Shern","year":"2021","journal-title":"J Clin Oncol"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.1007\/s11060-010-0342-2","article-title":"Pathological classification and molecular genetics of meningiomas","volume":"99","author":"Mawrin","year":"2010","journal-title":"J Neuro-Oncol"},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa1902688","article-title":"Gilteritinib or chemotherapy for relapsed or refractory FLT3-mutated AML","volume":"381","author":"Perl","year":"2019","journal-title":"N Engl J Med"},{"key":"B34","doi-asserted-by":"publisher","DOI":"10.1200\/jco.2015.64.0060","article-title":"Gemtuzumab ozogamicin versus best supportive care in older patients with newly diagnosed acute myeloid leukemia unsuitable for intensive chemotherapy: Results of the randomized phase III EORTC-GIMEMA AML-19 trial","volume":"34","author":"Amadori","year":"2016","journal-title":"J Clin Oncol"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.1200\/jco.2007.15.6315","article-title":"Allogeneic hematopoietic stem-cell transplantation for myeloid sarcoma: A retrospective study from the SFGM-TC","volume":"26","author":"Chevallier","year":"2008","journal-title":"J Clin Oncol"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1769002\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T04:24:14Z","timestamp":1783657454000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1769002\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,10]]},"references-count":35,"alternative-id":["10.3389\/fonc.2026.1769002"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2026.1769002","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,10]]},"article-number":"1769002"}}