1. MLAB 1415- Hematology Keri Brophy-Martinez
Myelodysplastic Syndromes

2. MYELODYSPLASTIC SYNDROMES
Acquired clonal disorders characterized by progressive cytopenias in the peripheral blood, reflecting defects in erythroid, myeloid and/or megakaryocytic maturation.
Impaired hematopoiesis.
Disrupted apoptosis
The origin is currently unknown

3. Terms used to describe MDS
Preleukemic leukemia or syndrome
Chronic refractory anemia with sideroblasts
Smoldering leukemia

4. Risk factors Age Occur primarily over the age of 50
Genetic predisposition
Chromosomes 5,7 and 8
Down’s, Fanconi’s
Environmental exposures
benzene
Prior therapy
Radiation
Chemotherapy

5. Clinical findings
Symptoms are related to progressive bone marrow failure
Infections
Bleeding
Anemia- fatigue/weakness
Death usually occurs from infection and/or bleeding or from leukemia if transformation occurs.

6. Key Lab Features of MDS Dysmyelopoiesis Dyserythropoiesis
Dysmegakaryopoiesis

7. Dysmyelopoiesis- PB

8. Dyserythropoiesis- PB
Dimorphic erythrocyte population
Oval macrocytes

9. Dysmegakaryopoiesis- PB
Abnormal platelet granulation
Micromegakaryocyte

10. FAB classification Five MDS subtypes: Refractory anemia (RA)
Refractory anemia with ringed sideroblasts (RARS)
Refractory anemia with excess blasts (RAEB)
Refractory anemia with excess blasts in transformation (RAEB-t)
Chronic myelomonocytic leukemia (CMML)

11. WHO classification- 2008
Refractory anemia (RA) with unilineage dysplasia
Refractory anemia with ringed sideroblasts (RARS)
Refractory cytopenia with multilineage dysplasia (RCMD)
RA with excess blasts (RAEB)
MDS with isolated deletion of 5q
MDS, unclassifiable
Childhood MDS

12. MDS/MPD Diseases
Clonal hematopoietic neoplasms that at initial presentation have some clinical, laboratory or morphological findings of both a MDS/MPD
Abnormalities in the regulation of myeloid proliferation, maturation and cell survival
Diseases
CMML associated with persistent monocytosis
Atypical Chronic Myeloid Leukemia
Juvenile Myelomonocytic Leukemia
MDS/MPD, unclassifiable

13. Chronic Myelomonocytic Leukemia (CMML)
Monocytosis
Dysplasia in one or more myeloid lines
Bone marrow hypercellular
Splenomegaly may be present

14. Therapy
Currently, there is no really good treatment for MDS, therefore most therapy is supportive, such as transfusion of blood components and antibiotics.
The only effective treatment is bone marrow transplant, but most patients are too old to survive the rigors of this treatment.
Immunosuppressive therapy decreases the chance of leukemic transformation.

15. References
McKenzie, Shirlyn B., and J. Lynne. Williams. "Chapter 21." Introduction. Clinical Laboratory Hematology. Boston: Pearson, Print
Rodak, Bernadette F., Fritsma, George, and Elaine Keohane. "Chapter 35." Myelodysplastic Syndrome. Hematology Clinical Principles and Applications. St. Louis: Elsevier, Print