Myelodysplasia

Question 1

What is myelodysplasia?

Answer 1

Group of conditions that manifest as marrow failure due to haematopoeitic stem cell damage characterised by chronic pancytopaenia with low reticulocyte count, + abnormal cellular maturation.

Question 2

List 5 subgroups of myelodysplasia

Answer 2

Refractory anaemia (RA): less RBCs  
RA with ringed sideroblasts (RARS)
RA with excess blasts (RAEB) 
Chronic myelomonocytic leukaemia (CMML) 
RAEB in transformation (RAEB-t)

Question 3

Describe the aetiology of myelodysplasia

Answer 3

PRIMARY (90%): intrinsic BM problem
SECONDARY (10%): previous chemo or radiotherapy
Pts may have chromosomal abnormalities

Question 4

List 5 risk factors for myelodysplasia

Answer 4

Chemotherapy
Radiotherapy
Occupational exposure to toxic chemicals
Down’s
Congenital neutropaenia

Question 5

Describe the epidemiology of myelodysplasia

Answer 5

Primary: 65-70s
Secondary: Younger
M > F
2 x as common as AML

Question 6

List 3 categories of symptoms of myelodysplasia

Answer 6

Anaemia (fatigue, dizziness, exercise intolerance)
Neutropaenia (recurrent infections)
Thrombocytopaenia (easy bruising, epistaxis)

Question 7

List 4 categories of signs of myelodysplasia

Answer 7

Anaemia (pallor, cardiac flow murmur)
Neutropaenia (infections)
Thrombocytopaenia (purpura or ecchymoses)
Spleen/liver/lymph N NOT enlarged (except in CMML)

Question 8

How may myelodysplasia present?

Answer 8

May be ASYMPTOMATIC + diagnosed on routine blood counts

Question 9

When is myelodysplasia diagnosed?

Answer 9

When BM demonstrates:
Significant dysplasia
Clonal cytogenetic abnormality
Quantitative changes in at least 1 blood cell line
Blasts < 20%.
(Pts with blasts ≥ 20% are considered to have AML)

Question 10

What bloods are taken in myelodysplasia?

Answer 10

FBC: pancytopaenia
Reticulocyte count: LOW
Folate + vitamin B12: NORMAL (excludes other ddx)
Iron studies: NORMAL (excludes other ddx)

Question 11

Describe the blood film in myelodysplasia

Answer 11

Normocytic or macrocytic red cells
Ringed sideroblasts in RARS
High monocytes in CMML

Question 12

Why perform bone marrow core biopsy for myelodysplasia?

Answer 12

to determine whether CMML has transformed to AML

Question 13

Why perform bone marrow cytogenic analysis in myelodysplasia?

Answer 13

to identify any chromosomal abnormalities

Question 14

Why is HLA typing used in myelodysplasia?

Answer 14

useful for stem cell transplantation

Question 15

What are sideroblasts?

Answer 15

nucleated erythroblasts with granules of iron accumulated in the mitochondria

Question 16

What can myelodysplasia develop into?

Answer 16

AML (30%)