9984/3 Refractory anemia with excess blasts in transformation




Tumours of haematopoietic and lymphoid tissues
ICD-O-3 topography code: C42 and C77
ICD10: C92.0

Refractory anemia with excess blasts in transformation (RAEB-T) is characterised by dysplastic features of the myeloid and usually erythroid progenitor cells in the bone marrow and an increased number of myeloblasts in the bone marrow. The blast count ranges from 20% to 30%. RAEB-T used to be a subcategory of myelodysplastic syndrome in the past. Recently, the term has been eliminated from the WHO based classification of myelodysplastic syndromes. The reason is that the percentage of bone marrow blasts required for the diagnosis of acute myeloid leukemia has been reduced to 20%. Currently, according to WHO classification, the vast majority of RAEB-T cases are best classified as acute leukemias (acute leukemias with multilineage dysplasia following myelodysplastic syndrome). A minority of cases are part of RAEB-2.

>>> The current term is refractory anemia with excess blasts 1
Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J, Vardiman JW (Eds.)
WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues
4th Edition
International Agency for Research on Cancer: Lyon 2008