Myelodysplasia (MDS) describes a group of acquired bone marrow disorders caused by a defect in haemopoietic stem cells. They are characterized by progressive bone marrow failure with quantitative and qualitative abnormalities in at least one of the three myeloid cell lines (red cells, granulocyte/monocytes and platelets

Risk of progression to AML

These disorders predominantly affect older adults, with a median age at diagnosis of 70-75 years.

Pancytopaenia 5 years post-chemotherapy/radiotherapy → ?myelodysplastic syndrome

Clinical features

Occurs mostly in elderly people and presents with symptoms of anaemia, infection or bleeding due to pancytopenia

MDS should be suspected in patients with otherwise unexplained cytopenias or macrocytosis.

Investigations

• Anaemia, thrombocytopenia, neutropenia
• Bone marrow cellularity can be increased, normal or reduced, irrespective of pancytopenia
• The percentage of bone marrow blast cells is important for classification and prognostic risk stratification in MDS. If this percentage rises above 20%, the diagnosis changes from MDS to AML.
• Ring sideroblasts seen with a specific iron stain are present in some subtypes.

Management

• Supportive care - red cell, platelet transufusions. control of bleeding and infections
• Tx depends on clinical burden of the disease, likely prognosis and age and fitness of the patient
  • Options include transfusion support alone, or for younger fitter patients allogeneic SCT can be considered as a potentially curative strategy