Table 1.

Criteria for chronic, accelerated, and blast phases of CML⁷

CML-CP	CML-AP	CML-BC
Must meet all of the following criteria:	Must meet 1 or more of the following criteria:	Must meet 1 or more of the following criteria:
Documentation of t(9;22) or the Bcr-Abl fusion gene	Blasts 10%-19% of peripheral blood white cells or bone marrow cells	Blasts ≥ 20% of peripheral blood white cells or bone marrow cells
Bone marrow blasts < 10%	Peripheral blood basophils at least 20%	Extramedullary blast proliferation
Does not meet any criteria for accelerated phase or blast crisis	Persistent thrombocytopenia (100 × 109/L) unrelated to therapy, or persistent thrombocytosis (1000 × 109/L) unresponsive to therapy	Large foci or clusters of blasts in bone marrow biopsy
	Increasing spleen size and increasing WBC count unresponsive to therapy
	Cytogenetic evidence of clonal evolution (ie, the appearance of an additional genetic abnormality that was not present in the initial specimen at the time of diagnosis of chronic phase CML)
	Megakaryocytic proliferation in sizable sheets and clusters, associated with marked reticulin or collagen fibrosis, and/or severe granulocytic dysplasia, should be considered as suggestive of CML-AP; these findings have not yet been analyzed in large clinical studies; however, so it is not clear whether they are independent criteria for accelerated phase; they often occur simultaneously with one or more of the other features listed

Like adults, most children will present in chronic phase.