Diagnostic criteria for chronic myelomonocytic leukemia (CMML)
| Persistent peripheral blood monocytosis greater than 1 × 109/L |
| No Philadelphia chromosome or BCR/ABL fusion gene |
| Fewer than 20% blasts4-150 in the blood or bone marrow |
| Dysplasia in one or more myeloid lineages. If myelodysplasia is absent or minimal, the diagnosis of CMML may still be made if the other requirements are present and: |
| an acquired, clonal cytogenetic abnormality is present in the marrow cells, or |
| the monocytosis has been persistent for at least 3 months and all other causes of monocytosis have been excluded |
| Diagnose CMML-1 when blasts fewer than 5% in blood and fewer than 10% in bone marrow |
| Diagnose CMML-2 when blasts are 5% to 19% in blood, or 10% to 19% in marrow, or if Auer rods are present and blasts are fewer than 20% in blood or marrow |
| Diagnose CMML-1 or CMML-2 with eosinophilia when the criteria above are present and when the eosinophil count in the peripheral blood is greater than 1.5 × 109/L |
| Persistent peripheral blood monocytosis greater than 1 × 109/L |
| No Philadelphia chromosome or BCR/ABL fusion gene |
| Fewer than 20% blasts4-150 in the blood or bone marrow |
| Dysplasia in one or more myeloid lineages. If myelodysplasia is absent or minimal, the diagnosis of CMML may still be made if the other requirements are present and: |
| an acquired, clonal cytogenetic abnormality is present in the marrow cells, or |
| the monocytosis has been persistent for at least 3 months and all other causes of monocytosis have been excluded |
| Diagnose CMML-1 when blasts fewer than 5% in blood and fewer than 10% in bone marrow |
| Diagnose CMML-2 when blasts are 5% to 19% in blood, or 10% to 19% in marrow, or if Auer rods are present and blasts are fewer than 20% in blood or marrow |
| Diagnose CMML-1 or CMML-2 with eosinophilia when the criteria above are present and when the eosinophil count in the peripheral blood is greater than 1.5 × 109/L |
In this classification of CMML, blasts include myeloblasts, monoblasts, and promonocytes.