Myelodysplastic Syndrome

Question 1

What are the three groups of clonal myeloproliferative disorders?

Answer 1

1. AML
2. Chronic Myeloproliferative disorders, CMPDs
3. Myelodysplastic Syndrome

Question 2

What kind of patients commonly develop MDS?

Answer 2

Older (> 50 yrs) patients especially males

Question 3

MDS is grouped into three categories

Answer 3

-Primary (de novo)
-Treatment - related to 2-5 years post chemo
-Inherited, very rare (pedi version of MDS in this category)

Question 4

MDS are often called….

Answer 4

Pre-leukemias

Question 5

Pre-leukemias can terminate in

Answer 5

AML

Question 6

In MDS stem cell DNA sequences acquire permanent mutations particularly involved what chromosomes?

Answer 6

Chromosome 5 & 7

Question 7

What cell can accumulate mutations involving chromosome 5 & 7?

Answer 7

Myeloid stem cell.

Question 8

How is it possible for there to be unique clones in MDS?

Answer 8

Unique stem cells accumulate mutations and become malignant. Unique malignant stem cells produce different populations of cells.

Question 9

Why are normal cells killed off in MDS?

Answer 9

MDS cells produce cytokines that kill of normal cells.

Question 10

Progressive peripheral blood cytopenias occur with…

Answer 10

Dyspoiesis in 1 or more cell lines

Question 11

All MDS have what kind of abnormal cell development?

Answer 11

Dyserythropoiesis - occurs first; see oval macrocytes (1st thought, megaloblastic anemia), megaloblastoid bone marrow with bizarre nRBCs, some ringed siderblasts & dimorphic RBCs

Question 12

Most MDS have what kind of abnormal cell development?

Answer 12

Dysmyelopoiesis - persistent basophilic cytoplasms, abnormal granules & nuclei, uneven cytoplasmic staining & occlusion Auer rods (even before it’s officially a leukemia).

Question 13

Some MDS have what kind of abnormal cell development?

Answer 13

Dysmegakaryopoiesis - Giant platelets, bizarre & monomuclear megakaryocytes and abnormal granules

Question 14

When is hyperproliferation seen in MDS?

Answer 14

Not until the disease transforms into leukemia

Question 15

What is a major clinical feature of MDS?

Answer 15

Cytopenias

Question 16

MDS can stay stable for years with the only sign of MDS is

Answer 16

dysplasia

Question 17

MDS clinical symptoms are

Answer 17

Fatigue, fever, and bleeding
Patients can be asymptomatic in early stages

Question 18

Megaloblastoid dyserythropoiesis in bone marrow manifest in peripheral blood as?

Answer 18

• Hgb <10 g/dL
  -Variable degrees of …
  -Aniso, poik, HJ bodies, bosophilic stippling, and bizarre nRBCs.

Question 19

Describe MDS’s neutropenia

Answer 19

Increase metas & myelos
There may be Auer rods
There may be pseudo-pelger-huet

Question 20

How would platelets look like in an MDS patient?

Answer 20

Giant platelets with circulating micromegakaryocytes / -blasts
similar to AMegL

Question 21

What are the general findings in a bone marrow from an MDS patient?

Answer 21

-Hypercellular due to erythroid hyperplasia
-Ringed sideroblasts common
-Megaloblastic dyserythropoiesis (hallmark finding)

Question 22

How does FAB classify MDS?

Answer 22

On morphology alone so it is limited. Each category is RA but with increasingly more severe problems overlaid on top of it.
=% blasts in bone marrow
=% blasts in peripheral blood (p.b.)
=+/- ringed sideroblasts
=% of monocytes
=Extent of cytopenias
=Degree of dyspoiesis (bizarre forms)

Question 23

List from least to increasing severity of MDS from the FAB classification

Answer 23

1.Refractory Anemia (RA)
2.Refractory Anemia w/ringed sideroblasts (RARS)
3.Refractory Anemia w/ excess blasts (RAEB)
4.Chronic Myelomonocytic Leukemia (CMML)
5.Refractory Anemia W/ Excess Blasts in Transformation (RAEBIT, or RAEB-t)

Question 24

What is the prognosis in RA patients with sq syndrome?

Answer 24

Good prognosis. It stands for stable deletion syndrome

Question 25

RARS stands for

Answer 25

Refractory Anemia w/ ringed sideroblasts

Question 26

RAEB stands for?

Answer 26

Refractory Anemia w/ excess blasts.

Question 27

MDS-U stands for

Answer 27

Myelodysplastic Syndrome unknown

Question 28

What are the primary findings of refractory cytopenia with unilineage dysplasia?

Answer 28

Oval macrocytes

Question 29

In RARS what can you explect to find?

Answer 29

Usually dimorphic RBC population
<5% blasts in bone marrow
More ringed sideroblasts (>15% of nucleated cells in bone marrow)

Question 30

In RAEB what can you expect to find in the blood smear and bone marrow?

Answer 30

-Cytopenias in 2 cell lines
-A lot of blasts
-May have pseudo-pelger-huet
-Bone marrow blasts between 5-20%

Question 31

In CMML, what can you expect to find in the blood smear and bone marrow?

Answer 31

Findings of RA
-Mostly monos in bone marrow >20%
-Leukocytosis instead of leukopenia
-Less than 5% blasts in peripheral blood
-Absolute peripheral blood monocytosis with morphological abnormalities always present

Question 32

A & B do better than __C__ & RAEB-t

Answer 32

a- RC
b- RARS
c - RAEB

Question 33

What are possible general cures for MDS?

Answer 33

Bone marrow transplant or biologic response modifiers (under investigation)