Myelodysplastic Syndromes Flashcards
What are myelodysplastic syndromes? (MDS)
Diverse group of diseases ranging from mild anemia to those that evolve into acute leukemia
MDS diagnostic morphological criteria
- Hard to diagnose by just peripheral blood
- Ineffective hematopoiesis increases apoptosis
One or more of following - Persistent/progressive cytopenia
- Dyserythropoiesis
- Dysmyelopoiesis
- Dysmegakaryopoiesis
Previous terms for myelodysplastic syndromes?
- Pre-leukemias
- Refractory anemias (didn’t respond to normal anemia treatment)
Demographics + risk factors
- 70 years median age
- Environmental and occupational products (ammonia, petrochemicals, benzene, low dose radiation)
MDS diagnostic morphological criteria for dyserythropoiesis
Wide variation…
- Oval macrocytes key
- Aniso and poik
- Dimorphic RBC population
- Sideroblasts- possibly ringed
- Pappenheimers
- Multinuclear
- HJ bodies
- Asynchronism
- Basophilic stippling
- Teardrops
- Schistocytes
- Acanthocytes
MDS diagnostic morphological criteria for dysmyelopoiesis
- Neutropenia in 60% of cases
- Hypogranulation- some agranular
- Occ hypergranular w/ large granules
- Usually hyposegmented PMNs with abnormal chromatin (pseudo PH)
- Asynchronous (basophilic zones = pseudo Dohle)
- Mixed eos and baso granules
- Hybrid myelomonocytes
MDS diagnostic criteria for dysmegakaryopoiesis
- Thrombocytopenia in 60% of cases
- Micromegakaryocytes
- Abnormal segmentation (hypo/hyper)
- Hypo or agranular
- Giant plateletes
MDS lab findings in blood for single lineage dysplasia (MDS-SLD)
- Unicytopenia (usually RBC)
- Blasts < 1%
- No Auer rods
Lab findings in bone marrow for MDS-SLD
- Unilineage dysplasia (usually RBC)
- Blasts < 1%
- No Auer rods
- Ringed sideroblasts <15% (usually occ)
Difference between MDS-SLD and MDS-MLD?
MDS-MLD has dysplasia in two or more myeloid lineages (neutrophil and/or erythroid precursors and/or megakaryocytes
Lab findings in blood for MDS-RS
- Cytopenias (single, bi or pan)
- Blasts <1%
- No Auer rods
Lab findings in bone marrow for MDS-RS
- Single dysplasia OR multi dysplasia in 2+ myeloid lines
- Blasts <5%
- No Auer rods
- Ringed sideroblasts > 15%
Lab findings in blood for MDS with excess blasts-1 (MDS-EB-1)
- Cytopenias
- Blasts < 5%
- No Auer rods
Lab findings in bone marrow for MDS-EB-1
- Uni or multi lineage dysplasia
- 5-9% blasts
- No Auer rods
Lab findings in blood for MDS-EB-2
- Cytopenias
- 5-19% blasts with OR without Auer rods
Lab findings in bone marrow for MDS-EB-2
- Uni or multilineage dysplasia
- 10-19% blasts with OR without Auer rods
Lab findings for MDS-EB2 multilineage erythroid/myeloid (doesn’t say if in blood or BM)
- Dysplasia
- 50% RBC precursors
- Myeloblasts < 20% and left shift
- May see Auer rods
Lab findings in blood for MDS associated with isolated del (5q)
- Cytopenia(s)
- Blasts < 1%
Lab findings in bone marrow for MDS associated with isolated del (5q)
- Single or multi lineage dysplasia
- Blasts < 5%
- No Auer rods
- Isolated del (5q)
Lab findings for chronic myelomonocytic leukemia (CMML)
- Increased WBC
- Higher monos, promonos, mature and immature granulocytes
- Blasts < 20%
- CMML-1: PB Blasts < 5%, BM Blasts <10%
- CMML-2: PB blasts 5-15%, BM blasts 10-19%
List other MDS/MPN combo diseases
- Atypical chronic myeloid leukemia (aCML)
- Juvenile myelomonocytic leukemia (JMML)
- MDS/MPN with ringed sideroblasts + thrombocytosis - MDS/MPN, unclassified
Causes of secondary or therapy-related MDS
- Secondary to treatment of other malignancy (chemo or radiation)
- Toxins, such as benzene
