Chronic Myeloid Leukemia (CML) BCR-ABL 1+

Elevated WBC count with <5% blasts, a granulocytosis with left shift, basophilia. Thrombocytosis is a common finding.
Bone marrow is hyperplastic with marked expansion of myelopoiesis with complete maturation, < 20% blasts, but usually <10%. Megakaryopoiesis show characteristic features: increase of small megakaryocytes with a central hypolobulated nucleus. No other dysplastic morphological features are found.
Molecular investigation for the presence of the BCR-ABL1 fusion should always be performed to confirm diagnosis.

Diagnostic tabel for MPN