Myelodysplastic Syndromes

Question 1

How many cells must be counted

when assessing for Myeloid neoplasms?

Answer 1

• Peripheral blood
  
  • manual count of 200 cells
• Marrow
  
  • manual count of 500 cells

Question 2

What is the definition of

Myelodysplastic syndrome?

Answer 2

• cytopenias
• dyspoiesis
• tendency to develop acute leukemia

Question 3

What is the epidemiology of

MDS?

Answer 3

• usually affects older adults
• younger adults get it secondary to chemotherapy
• radiation
• benzene
• inherited marrow conditions like Fanconi anemia

Question 4

What are some of the common morphologic findings

in MDS?

Answer 4

• 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

Question 5

What are some common findings in

Erythroids of MDS?

Answer 5

• 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)

Question 6

What is the definition of a ringed sideroblast?

Answer 6

• must have 5 siderosomes that surround at least 1/3 of the nucleus
• significant when:
  
  • > 15% OR
  • > 5% with SF3B1 mutation

Question 7

What are some common findings

with granulocytes (myeloids)?

Answer 7

• mature granulocytes show neutropenia
• abnormal cytoplasmic granulation
• abnormal nuclear segmentation
  
  • Pseudo Pelger-Huet anomaly
• precursors are left shifted and/or megaloblastoid

Question 8

What is the differential diagnosis

for dyspoisis?

Answer 8

• 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

Question 9

What are the most common cytogenetic

abnormalities in MDS?

Answer 9

• complex cytogenetics are most common
• Followed by:
  
  • monosomy 7 or 7q-
  • isolated 5q-
  • del 20q

Question 10

What are the favorable cytogenetics ?

Answer 10

• del 5q and del 20q

Question 11

What is unique about MDS with deltion 5q?

Answer 11

• results from loss of long arm of chromosome 5
  
  • with or without 1 additional cytogenetic abnormality
    
    • NOT 7q-
• affects elderly women
• indolent clinical course
• thrombocytosis with anemia are seen
• Bone marrow: characteristic
  
  • monolobate megakaryocytes
• can have JAK2 mutation

Question 12

What are the peripheral blood findings of MDS with

single lineage dysplasia?

Answer 12

• anemia or thrombocytopenia or neutropenia
• No blasts (< 1%) or Auer rods
• No monocytosis ( < 1000/uL)

Question 13

What are the bone marrow findings

of MDS wih single lineage dysplasia?

Answer 13

• unilineage dysplasia
• < 5% blasts and no Auer rods
• < 15% ringed sideroblasts

Question 14

What are the peripheral blood findings in

MDS with single lineage dysplasia

and ring sideroblasts?

Answer 14

• anemia +/- dimorphic RBCs
• pappenheimer bodies
• no blasts ( < 1%) or Auer rods
• no monocytosis ( < 1000/uL)

Question 15

What are the bone marrow findings of MDS

with single lineage dysplasia and

ring sideroblasts?

Answer 15

• dysplastic erythroids
• < 5% blasts and no Auer rods
• > 15 % ring sideroblasts OR
  
  • > 5% ring sideroblasts with SF3B1 mutation

Question 16

What are the peripheral blood findings in

MDS with multilineage dysplasia?

Answer 16

• bi or pancytopenia
• < 1 % blasts
• No Auer rods

Question 17

What are the bone marrow findings of

MDS with multilineage dysplasia ?

Answer 17

• < 5 % blasts and no Auer rods
• dysplasia in > 10 % of > 1 cell line
• < 15% ring sideroblasts

Question 18

What are the peripheral blood findings

of MDS with multilineage dysplasia

and ring sideroblasts?

Answer 18

• bi or pancytopenia
• < 1 % blasts
• No Auer rods

Question 19

What are the bone marrow findings in MDS

with multilineage dysplasia and ring

sideroblasts?

Answer 19

• < 5 % blasts and no Auer rods
• dysplasia in > 10 % of > 1 cell line
• > 15 % ringed sideroblasts OR
  
  • > 5 % ring sideroblasts if SF3B1 mutation

Question 20

What are the peripheral blood findings

in MDS with excess blasts?

Answer 20

• bi or pancytopenia
• < 5% blasts, no Auer rods
  
  • MDS-EB1
• 5-19% blasts or Auer rods
  
  • MDS-EB2

Question 21

What are the bone marrow findings

for MDS with excess blasts?

Answer 21

• dysplasia
• 5-9 % blasts, no Auer rods
  
  • MDS-EB1
• 10-19% blasts, no Auer rods
  
  • MDS-EB2

Question 22

What are the peripheral blood findings

in MDS with isolated deletion 5q?

Answer 22

• anemia, normal to increased platelets
• < 5 % blasts
• No auer rods

Question 23

What are the bone marrow findings in

MDS with isolated del5q?

Answer 23

• hypolobated megakaryocytes (key)
• < 5% blasts and no Auer rods
• Karyotype:
  
  • 5q- with 1 additional abnormality
  • NOT 7q-