Myelodysplastic Syndromes

Question 1

Myelodysplastic Syndromes (MDS) definition

Answer 1

stem cell disorders characterized by pancytopenia w/ maturation abnormalities

Question 2

2 types of MDS

Answer 2

primary (de novo) - most of all idiopathic

secondary to therapy - chemo / radiation

Question 3

Etiology of MDS

Answer 3

result from proliferation of abnormal cells - affects myeloid line mutation may be caused by chemical exposure, radiation or viral infection

Question 4

Epidemiology of MDS

Answer 4

>50 yrs (median 70)

slight male predominance

Question 5

Symptoms of MDS

Answer 5

asymptomatic

anemia symptoms

thrombocytopenia symptoms

neutropenia symptoms

Question 6

Cellular Abnormalities of MDS

Answer 6

dysplasia including dyserythropoiesis, dysmyelopoiesis, dysmegakaryopoiesis

Question 7

Dyserythropoiesis

Answer 7

defective development of RBCs

most common are oval macrocytes

MACRO, NORMO classification

Question 8

Dysmyelopoiesis

Answer 8

abnormal granulation, hyposegmentation, possible left shift in the neutrophil line

Question 9

Dysmegakaryopoiesis

Answer 9

giant platelets, abnormal platelet granulation small or abnormal megakaryocytes

Question 10

Lab findings of MDS in PB

Answer 10

cytopenias & dysplasia (abnormal everything)

macro, normo anemia

oval macrocytes

RBC inclusions & NRBCs

Question 11

Lab findings of MDS in BM

Answer 11

hypercellular!

all cell lines exhibit dysplasia

giant nucleated RBC precursors

ringed sideroblasts!

Question 12

FAB classification of MDS

Answer 12

1. Refractory Anemia (RA)
2. Refractory anemia w/ ringed sideroblasts (RARS)
3. Refractory anemia w/ excess blast (RAEB)
4. Chronic myelomonocytic leukemia (CMML)
5. Refractory anemia with excess blasts in transformation (RAEB-t)

Question 13

Refactory Anemia (RA) - FAB

Answer 13

blasts in PB -<1%

blasts in BM- <5%

ringed sideroblasts - <15%

monos in BM - normal

Question 14

RA with ringed sideroblasts (RARS) - FAB

Answer 14

blasts in PB- 1%

blasts in BM-<5%

ringed sideroblasts- 15%!!!

monos in BM - normal

Question 15

RA with excess blasts (RAEB) - FAB

Answer 15

blasts in PB- <5%!!

blasts in BM - 5-20%!!!

ringed sideroblasts - variable

monos in BM - increased!!

Question 16

RAEB in transformation (RAEB-t) - FAB

Answer 16

blasts in PB- >5%!!!!

blasts in BM - 21-30%!!!

ringed sideroblasts - variable

monos in BM - normal

Question 17

Chronic Myelomonocytic leukemia (CMML) - FAB

Answer 17

blasts in PB- >5%

blasts in BM-<20%!

ringed sideroblasts- variable

monos in BM - normal

Question 18

WHO classification of MDS

Answer 18

1. RA
2. RARS
3. Refractory cytopenia w/ multilineage dysplasia (RCMD)
4. RAEB (1 and 2)
5. MDS associated w/ isolated del (5q syndrome)
6. MDS, unclassified (MDS-U)

Question 19

RA - WHO

Answer 19

PB- anemia, rare or no blasts

BM- Erythroid dysplasia only, <15% ringed sideroblasts

Question 20

RARS - WHO

Answer 20

PB - anemia, rare or no blasts

BM - Erythroid dysplasia only, 15% ringed sideroblasts (!!)

Question 21

RCMD - WHO

Answer 21

PB - cytopenias, rare or no blasts

BM - multilineage dysplasia, <15% ringed sideroblasts

Question 22

RAEB 1 -WHO

Answer 22

PB - cytopenias, <5% blasts

BM - unilineage or multilineage dysplasia, 5-9% blasts!!

Question 23

RAEB-2 WHO

Answer 23

PB- cytopenias, 5-19% blasts, AUER RODS PRESENT

BM- unilineage or multilineage dysplasia, 10-15% blasts!!!!, AUER RODS PRESENT

Question 24

5q- syndrome WHO

Answer 24

PB - anemia, normal or INCREASED PLT, <5% blasts Isolated deletion of 5q cytogenetic abnormality

Question 25

MDS - U WHO

Answer 25

PB- cytopenias, rare or no blasts BM- unilineage dysplasia, \<5% blasts

Question 26

Variants of MDS

Answer 26

1. hypoplastic MDS 2. Therapy related MDS 3. Childhood MDS

Question 27

Hypoplastic MDS

Answer 27

the 10% of MDS cases that have hypocellular BM difficult to distinguish from aplastic anemia

Question 28

Therapy related MDS

Answer 28

MDS secondary to chemo/ radiation highest incidence occurs 3-8 years after treatment

Question 29

Childhood MDS

Answer 29

few cases have been reported probably more but not correctly diagnosed

Question 30

Cytogenetic Abnormalities that contribute to MDS

Answer 30

additional copy of chromosome 21 addition on chromosome 8 loss on chromosome 7 inversion on chromosome 3 del 5q