Table 1. Myelodysplastic Syndromes: Comparison of the FAB and WHO Classifications
| FAB (1982) | WHO (2008) |
| AML = acute myeloid leukemia; FAB = French-American-British classification scheme; MDS = myelodysplastic syndromes; WHO = World Health Organization. | |
| Myelodysplastic Syndromes | |
| Refractory anemia. | Refractory anemia. |
| Refractory cytopenia with multilineage dysplasia. Refractory cytopenia with unilineage dysplasia. | |
| Refractory anemia with ring sideroblasts. | Refractory anemia with ring sideroblasts. |
| Refractory anemia with excess blasts. | Refractory anemia with excess blasts -1 and -2. |
| Myelodysplastic syndrome, unclassifiable. | |
| Myelodysplastic syndrome associated with del(5q). | |
| Reclassified from MDS to: | |
| Refractory anemia with excess blasts in transformation. | Acute myeloid leukemia identified as AML with multilineage dysplasia following a myelodysplastic syndrome. |
| Chronic myelomonocytic leukemia. | Myelodysplastic and myeloproliferative diseases. |
