{"entity":{"id":"blasts","kind":"term","name":"Blasts (leukaemic blast cells)","aka":["blast count","blast percentage","leukaemic blasts","leukemic blasts","myeloblasts","lymphoblasts","blast crisis","blast phase","excess blasts","circulating blasts"],"tldr":"Immature blood cells that should mature in the marrow but in acute leukaemia multiply without growing up. The percentage of blasts in the marrow defines the disease: 20% or more is acute leukaemia.","summary":"Normal marrow has under 5% blasts; MDS with excess blasts has 5-19%; AML or ALL is diagnosed at ≥20% (or with defining genetic lesions at lower counts under WHO 2022/ICC). Blasts crowd out normal blood production, causing anaemia, infection and bleeding, and very high counts (hyperleukocytosis) can clog vessels. Remission is defined as under 5% marrow blasts with recovered counts, though flow cytometry and molecular MRD now detect disease far below that. In CML, progression from chronic phase to blast crisis (≥20% blasts) transforms a controllable disease into an acute leukaemia.","asOf":"2026-09-09","wikipedia":"https://en.wikipedia.org/wiki/Blast_cell","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Blast_cell"}],"tags":[],"related":["flow-cytometry","mds","complete-response-term","philadelphia-chromosome"],"cancers":["aml","all-leukemia"],"sections":["diagnostics"],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Pathology"},"route":"/terms/blasts/","neighbours":{"term":[{"id":"complete-response-term","kind":"term","name":"Complete response (CR) and partial response (PR)","route":"/terms/complete-response-term/"},{"id":"dipss-mipss70","kind":"term","name":"DIPSS, DIPSS-plus and MIPSS70 (myelofibrosis risk scores)","route":"/terms/dipss-mipss70/"},{"id":"flow-cytometry","kind":"term","name":"Flow cytometry (immunophenotyping)","route":"/terms/flow-cytometry/"},{"id":"ipss-m-ipss-r","kind":"term","name":"IPSS-R and IPSS-M (myelodysplastic syndrome risk scores)","route":"/terms/ipss-m-ipss-r/"},{"id":"philadelphia-chromosome","kind":"term","name":"Philadelphia chromosome (Ph+, BCR::ABL1)","route":"/terms/philadelphia-chromosome/"},{"id":"sokal-elts-scores","kind":"term","name":"Sokal and ELTS risk scores (chronic myeloid leukaemia)","route":"/terms/sokal-elts-scores/"}],"cancer":[{"id":"all-leukemia","kind":"cancer","name":"Acute lymphoblastic leukaemia","route":"/cancers/all-leukemia/"},{"id":"aml","kind":"cancer","name":"Acute myeloid leukaemia","route":"/cancers/aml/"},{"id":"cml-advanced-phase","kind":"cancer","name":"Chronic myeloid leukaemia, accelerated and blast phase","route":"/cancers/cml-advanced-phase/"},{"id":"cmml","kind":"cancer","name":"Chronic myelomonocytic leukaemia and MDS/MPN overlap neoplasms","route":"/cancers/cmml/"},{"id":"mds","kind":"cancer","name":"Myelodysplastic syndromes / neoplasms (MDS)","route":"/cancers/mds/"}],"section":[{"id":"diagnostics","kind":"section","name":"Diagnostics & Biomarkers","route":"/fronts/diagnostics/"}]}}