{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T09:56:27Z","timestamp":1790934987793,"version":"4.1.0"},"reference-count":28,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T00:00:00Z","timestamp":1790899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>In \u201cbilineal\u201d mixed-phenotype acute leukemia (MPAL), the proportions of lymphoid and myeloid leukemic cells may differ substantially. A myeloid component may constitute &lt;10% of bone marrow (BM) cells and show subtle immunophenotypic abnormalities detectable by multicolor flow cytometry (MFC). The significance of minor myeloid leukemic populations in otherwise acute lymphoblastic leukemia (ALL), including their association with lineage switch, remains uncertain. We retrospectively reviewed diagnostic MFC data from 5094 children with B-cell precursor or T-cell ALL. An additional minor myeloid leukemic population (&lt;10% of BM) was identified in 92 ALL cases (1.8%), with a median of 3.0% of BM cells (0.2\u20139.2%). The frequency of ALL cases harboring a minor myeloid leukemic population was comparable to that of overt \u201cbilineal\u201d MPAL (with both populations \u2265 10% of BM cells), diagnosed during the same period. The myeloid populations expressed CD33, CD64, CD14, lysozyme, and markers shared with the dominant lymphoblastic population (CD19\/CD7, CD34, CD117). Common genetic findings were high hyperdiploidy (n = 14), KMT2A rearrangements (n = 13), and BCR::ABL1 (n = 8). Although no expansion was documented in most patients, 6 of 83 newly diagnosed patients (7.2%) developed lineage switch to acute myeloid leukemia or overt \u201cbilineal\u201d MPAL. Most cases were managed successfully with standard ALL-directed therapy.<\/jats:p>","DOI":"10.3390\/ijms27198816","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T09:10:48Z","timestamp":1790932248000},"page":"8816","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Minor Myeloid Leukemic Populations in Pediatric Acute Lymphoblastic Leukemia: A Potentially Underrecognized Mixed-Phenotype Tumor?"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7082-1694","authenticated-orcid":false,"given":"Alexandra","family":"Semchenkova","sequence":"first","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Polina","family":"Lavrova","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Vladimir","family":"Kozeev","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4317-2094","authenticated-orcid":false,"given":"Irina","family":"Demina","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3450-0498","authenticated-orcid":false,"given":"Ekaterina","family":"Mikhailova","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Julia","family":"Roumiantseva","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"given":"Svetlana","family":"Lagoyko","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"given":"Anna","family":"Kazakova","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Galina","family":"Novichkova","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"given":"Alexander","family":"Karachunskiy","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9634-5828","authenticated-orcid":false,"given":"Elena","family":"Zerkalenkova","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0889-6986","authenticated-orcid":false,"given":"Alexander","family":"Popov","sequence":"additional","affiliation":[{"name":"Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela St., Moscow 117198, Russia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1541","DOI":"10.1056\/NEJMra1400972","article-title":"Acute lymphoblastic leukemia in children","volume":"373","author":"Hunger","year":"2015","journal-title":"N. 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