Bone marrow neoplastic
Bone marrow - neoplastic myeloid
Myelodysplastic syndromes (MDS)
MDS with excess blasts
Author: Nikhil Sangle, M.D.
Last author update: 1 August 2011
Last staff update: 11 August 2022
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: MDS with excess blasts[TI]
Table of Contents
Definition / general | Laboratory | Case reports | Microscopic (histologic) description | Microscopic (histologic) images | Molecular / cytogenetics description | Differential diagnosisCite this page: Sangle N. MDS with excess blasts. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/myeloproliferativeRAEB.html. Accessed March 21st, 2023.
Definition / general
- Myeloblasts are 5 - 19% of bone marrow differential
- Usually cytopenias in 2 or 3 lineages
- Considered high risk MDS
- Type 1: 5 - 9% blasts in bone marrow or 2 - 4% blasts in peripheral blood, no Auer rods, < 1 billion/L monocytes
- Type 2: 10 - 19% blasts in bone marrow or 5 - 19% blasts in peripheral blood or Auer rods in any MDS, < 1 billion/L monocytes; more aggressive, greater tendency to progress to AML (Am J Clin Pathol 2005;124:191)
- Refractory anemia with excess blasts in transformation (RAEB-T): classified as AML under WHO classification
- Median survival of 16 months for RAEB-1 and 9 months for RAEB-2 (Br J Haematol 2006;132:162)
Laboratory
- Anemia (normochromic, normocytic or macrocytic), usually neutropenia and thrombocytopenia
Case reports
- 31 year old man with cutaneous involvement (Cutis 2007;80:223)
- 64 year old woman with extensive myocardial infiltration (BMC Blood Disord 2006;6:4)
Microscopic (histologic) description
- Peripheral blood: nucleated red blood cells, immature granulocytes, neutrophilic hyposegmentation, pseudo-Pelger-Huet cells and hypogranulation, myeloblasts 2 - 4% (RAEB-1) or 5 - 19% (RAEB-2), occasional micromegakaryocytes
- Bone marrow: normocellular or hypercellular; hyperplasia of granulocytes or erythrocytes; myeloblasts comprise 5 - 9% (RAEB-1) or 10 -19% (RAEB-2) of white blood cells; Auer rods often seen; severe dysplastic changes in all 3 lineages, more severe than other MDS; abnormal localization of immature precursors (ALIP / clusters or aggregates of blasts located away from bone trabeculae and vascular structures); may have increased reticulin fibers
Microscopic (histologic) images
AFIP images
Neutrophil has hypogranular cytoplasm
Hypogranular cytoplasm
Blast in center with adjacent neutrophils
Promyelocytes and myelocytes
Markedly hypogranular cytoplasm
Auer rod present in blast; neutrophils show nuclear hypolobulation
Normocellular biopsy
Normal erythroid precursors
Slightly more cellular marrow
More immature granulocytes
Marked fibrosis with streaming effect
Bone marrow aspirate
Images hosted on other servers:
RAEB-1:
Various images
RAEB-2:
Blood, marrow and myocardial infiltration
Molecular / cytogenetics description
- No specific abnormality (Atlas of Genetics and Cytogenetics)
Differential diagnosis
- Copper deficiency: reduced copper levels (Leuk Res 2008;32:495)
