Myelodysplastic Syndromes Flashcards
How many cells must be counted
when assessing for Myeloid neoplasms?
- Peripheral blood
- manual count of 200 cells
- Marrow
- manual count of 500 cells
What is the definition of
Myelodysplastic syndrome?
- cytopenias
- dyspoiesis
- tendency to develop acute leukemia
What is the epidemiology of
MDS?
- usually affects older adults
- younger adults get it secondary to chemotherapy
- radiation
- benzene
- inherited marrow conditions like Fanconi anemia
What are some of the common morphologic findings
in MDS?
- hypercellular marrow, poliferation and apoptosis of cells
- blasts are < 20% (in blood or bone marrow)
- dyspoiesis in at least 10% of 1 cell line
- Erythroids, megakaryocytes, and granulocytes can have many findings
- cytopenias are seen
- NO splenomegaly
What are some common findings in
Erythroids of MDS?
- mature erythrocytes show basophilic stippling, poikilocytosis and macrocytosis
- precursors can be megaloblastoid with nuclear lobation
- internuclear bridging
- multinuclearity
- cytoplasmic PAS positive
- cytoplasmic vacuolization (also can be seen in copper deficiency)
- karyorrhexis
- incresed ringed sideroblasts
- increased susceptibility to complement mediated lysis (positive Heme test)
What is the definition of a ringed sideroblast?
- must have 5 siderosomes that surround at least 1/3 of the nucleus
- significant when:
- > 15% OR
- > 5% with SF3B1 mutation
What are some common findings
with granulocytes (myeloids)?
- mature granulocytes show neutropenia
- abnormal cytoplasmic granulation
- abnormal nuclear segmentation
- Pseudo Pelger-Huet anomaly
- precursors are left shifted and/or megaloblastoid
What is the differential diagnosis
for dyspoisis?
- Vitamin B12 and Folate deficiency
- alcohol consumption
- HIV infection
- Lead or arsenic poisoning
- Copper deficiency/Zinc poisoning
- prominent erythroid vacuolization
- iron laden plasma cells are clue
- Medications
- isoniazid, chloramphenicol, chemo
What are the most common cytogenetic
abnormalities in MDS?
- complex cytogenetics are most common
- Followed by:
- monosomy 7 or 7q-
- isolated 5q-
- del 20q
What are the favorable cytogenetics ?
- del 5q and del 20q
What is unique about MDS with deltion 5q?
- results from loss of long arm of chromosome 5
- with or without 1 additional cytogenetic abnormality
- NOT 7q-
- with or without 1 additional cytogenetic abnormality
- affects elderly women
- indolent clinical course
- thrombocytosis with anemia are seen
- Bone marrow: characteristic
- monolobate megakaryocytes
- can have JAK2 mutation
What are the peripheral blood findings of MDS with
single lineage dysplasia?
- anemia or thrombocytopenia or neutropenia
- No blasts (< 1%) or Auer rods
- No monocytosis ( < 1000/uL)
What are the bone marrow findings
of MDS wih single lineage dysplasia?
- unilineage dysplasia
- < 5% blasts and no Auer rods
- < 15% ringed sideroblasts
What are the peripheral blood findings in
MDS with single lineage dysplasia
and ring sideroblasts?
- anemia +/- dimorphic RBCs
- pappenheimer bodies
- no blasts ( < 1%) or Auer rods
- no monocytosis ( < 1000/uL)
What are the bone marrow findings of MDS
with single lineage dysplasia and
ring sideroblasts?
- dysplastic erythroids
- < 5% blasts and no Auer rods
- > 15 % ring sideroblasts OR
- > 5% ring sideroblasts with SF3B1 mutation
What are the peripheral blood findings in
MDS with multilineage dysplasia?
- bi or pancytopenia
- < 1 % blasts
- No Auer rods
What are the bone marrow findings of
MDS with multilineage dysplasia ?
- < 5 % blasts and no Auer rods
- dysplasia in > 10 % of > 1 cell line
- < 15% ring sideroblasts
What are the peripheral blood findings
of MDS with multilineage dysplasia
and ring sideroblasts?
- bi or pancytopenia
- < 1 % blasts
- No Auer rods
What are the bone marrow findings in MDS
with multilineage dysplasia and ring
sideroblasts?
- < 5 % blasts and no Auer rods
- dysplasia in > 10 % of > 1 cell line
- > 15 % ringed sideroblasts OR
- > 5 % ring sideroblasts if SF3B1 mutation
What are the peripheral blood findings
in MDS with excess blasts?
- bi or pancytopenia
- < 5% blasts, no Auer rods
- MDS-EB1
- 5-19% blasts or Auer rods
- MDS-EB2
What are the bone marrow findings
for MDS with excess blasts?
- dysplasia
- 5-9 % blasts, no Auer rods
- MDS-EB1
- 10-19% blasts, no Auer rods
- MDS-EB2
What are the peripheral blood findings
in MDS with isolated deletion 5q?
- anemia, normal to increased platelets
- < 5 % blasts
- No auer rods
What are the bone marrow findings in
MDS with isolated del5q?
- hypolobated megakaryocytes (key)
- < 5% blasts and no Auer rods
- Karyotype:
- 5q- with 1 additional abnormality
- NOT 7q-
