Atypical Chronic Myeloid Leukemia

**Semantic type:** Neoplastic Process

**Definition:** A myelodysplastic/myeloproliferative neoplasm characterized by the presence of leukocytosis with increased numbers of neutrophils, promyelocytes, myelocytes, and metamyelocytes; blasts less than 20% in bone marrow and peripheral blood; dysgranulopoiesis; minimal or absent monocytosis; absence of eosinophilia; and presence of bone marrow hypercellularity with granulocytic proliferation and granulocytic dysplasia. Dysplasia in the erythroid and megakaryocytic lineages may be present or absent. No evidence of BCR/ABL fusion is present.

**Synonyms:** - Atypical CML - Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative - Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative - Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative - Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative - Atypical Chronic Myeloid Leukemia, BCR::ABL1 Negative - MDS/MPN-N - Myelodysplastic/Myeloproliferative Neoplasm with Neutrophilia - Subacute Granulocytic Leukemia - Subacute Myelogenous Leukemia - Subacute Myeloid Leukemia - Subacute granulocytic leukemia - Subacute myelogenous leukemia - Subacute myeloid leukemia - aCML