HAEMATOLOGY - MYELODYSPLASIA

Question 1

What is myelodysplastic syndrome?

Answer 1

An acquired neoplasticism disorder of haematopoetic stem cells
It’s a pre-leukaemia stage that may progress to AML

Question 2

What age does MDS usually affect?

Answer 2

Any age but more common after the age of 60

Question 3

What is the pathophysiology of MDS?

Answer 3

Haematopoietic stem cells are damaged so can’t mature and persist as blast cells
Blast cell numbers increase which displaces and reduces the normal cells.

Question 4

Whats the cause of MDS?

Answer 4

Mostly unknown - primary
Can be caused by chemo or radiation therapy (secondary) - this is rare

Question 5

Whats the most common feature of MDS?

Answer 5

Anaemia symptoms
Increased risk of infections
Excessive bruising and easy bleeding

Question 6

What can MDS progress into? How common is this?

Answer 6

40-50% of the time MDS progresses into AML

Question 7

How do you diagnose MDS/

Answer 7

FBC -to look for cytopenias
Peripheral blood smear - big oval-shaped RBC, abnormal WBC and Plt
Bone marrow aspiration and biopsy - increased cell count with dysplastic changes in any of the blood types. Percentage of bone marrow plant cells is important (if rising above 20% then diagnosis is then AML)
Chromosome analysis - genetic abnormalities

Question 8

How is MDS risk status assessed?

Answer 8

using international prognostic scoring systems that incorporate blood counts, bone marrow blast percentage and cytogenetics

Question 9

How is low risk MDS treated?

Answer 9

EPO growth factors to stimulates production of RBC
Lenalidomide for those with the chromosomal abnormalities 5q-
Immunosuppressive therapy with anti-thymocyte globulin or Ciclosporin
Transfusions and antibiotics. (Note: give iron chelation to those with secondary iron overload from transfusions)

Question 10

How is high risk MDS treated?

Answer 10

Hypomethylating agents - aim to prevent leukaemia
Bone marrow stem cell transplant - the only curative treatment
Intensive chemotherapy

Question 11

What are examples of hypomethylating agents used to treat MDS?

Answer 11

Azacitidine and decitabine

Question 12

What are immunosuppressive agents used to treat MDS?

Answer 12

Ciclosporin and antithymocyte globulin

Question 13

Who should myelodysplasia be suspected in?

Answer 13

Those with otherwise unexplained cytopenias or macrocytosis

Question 14

What conditions are an overlap of myelodysplasia and myeloproliferative neoplasms?

Answer 14

CML
atypical CML (BCR-ABL negative)
Juvenile myelomonocytic leukaemia
MDS/MPN with ring sideroblastic and thrombocytopenia
MDS/MPN unclassifiable

Question 15

What can cause teardrop cells?

Answer 15

Myelofibrosis
Megaloblastic anaemia
Thalassameua