Myelodysplastic (or Dysmyelopoietic) Syndromes Flashcards
- Primary (de novo)
- Treatment-related (2-5 years post chemotherapy)
- Very rarely, inherited
3 types of diseases for Myelodysplastic syndromes
- chromosomes 5 & 7
- Defect in the Myeloid Stem Cell
Myelodysplastic syndrome etiology
ineffective clonal hematopoiesis
too few cells
morphological dysplasia
ugly cells
______ are a major feature of MDS
Cytopenias
Hyperproliferation is NOT seen until the disease transforms into ______
leukemia
MDS has progressive ____ (all cell lines can be affected)
cytopenia
HALLMARK FINDING of MDS in the bone marrow IS MEGALOBLASTOID ________
Dyserythropoiesis
Each MDS is pretty much a basic ___ ____ but with increasingly more severe problems
refractory anemia
1st in order of increasing severity
Refractory anemia (RA)
2nd in order of increasing severity
Refractory anemia with ringed sideroblasts (RARS)
3rd in order of increasing severity
Refractory anemia with excess sideroblasts
4th in order of increasing severity
Chronic myelomonocytic leukemia (CMML)
5th in order of increasing severity
Refractory anemia with excess blasts in transformation (RAEBIT or RAEB-t)
Some patients will actually progress through each MDS classification before it becomes ___!
AML
- Refractory Anemia (RA)
- Refractory anemia with ringed sideroblasts (RARS)
- Refractory anemia with excess blasts (RAEB)
- Condition called MDS unclassified (MDS-U)
WHO subgroups of MDS
Refractory cytopenia with unilineage dysplasia
Also known as Refractory Anemia
Primary finding is anemia with oval macrocytes and nRBCs
Refractory cytopenia with unilineage dysplasia
Rare ringed sideroblasts <15% & siderocytes
Refractory cytopenia with unilineage dysplasia
Normal B12 and folate normal
General MDS lab findings
<5% bone marrow blasts
Megaloblastoid picture
Refractory cytopenia with unilineage dysplasia
MORE ringed sideroblasts >15% of nucleated cells in bone marrow
RARS - refractory anemia with ringed sideroblasts
dimorphic RBC population
RARS
RA with cytopenia in 2 cell lines now & more blasts
RAEB - refractory anemia with excess blasts
bone marrow blasts up to 5-20%
RAEB
RA, but mostly monos in the bone marrow
CMML - chronic myelomonocytic leukemia
leukocytosis instead of leukopenia
CMML
Absolute p.b. monocytosis with morphological abnormalities ALWAYS present
CMML
WBC count Normal to decreased
RC, RARS, RAEB
Dysgranulopoiesis ++
CMML and RAEB
Dyserythropoiesis +++
RC and RARS
Megaloblastoid bone marrow with bizarre nRBCs
myelodysplastic syndromes MDS
Most frequent aneuploidy (abnormalities) found in MDS
Trisomy 8 and monosomy 7
Ineffective hematopoiesis and morphological dysplasia
MDS characteristics
