• Clinical science

Myelodysplastic syndromes


Myelodysplastic syndromes (MDS) are a group of hematological cancers in which malfunctioning pluripotent stem cells lead to hypercellularity and dysplasia of the bone marrow. This, in turn, leads to cytopenia of one or more cell lines (thrombocytopenia, erythrocytopenia, leukocytopenia). Most cases of MDS have a primary, idiopathic etiology, while a minority of cases are secondary to an underlying cause. MDS usually affects elderly patients and has a slowly progressive course. Clinical features vary depending on the type of MDS and the affected cell lines, and may include signs of anemia (e.g., fatigue, weakness, pallor), recurrent infections, and/or petechial bleeding. Diagnosis of MDS requires blood tests, bone marrow biopsy, and possibly genetic analysis. While mild cases may be closely monitored, severe disease typically requires blood transfusions supplemented with erythropoietin, vitamins, and, in some cases, granulocyte colony-stimulating factor. Medical therapy (e.g., chemotherapy or immunosuppressants) may also help to manage the disease, but allogenous stem cell transplantation is the only curative treatment. In 30% of cases, the disease progresses to acute myeloid leukemia.




WHO Classification of Primary Myelodysplastic Syndromes

  • The WHO classification distinguishes between eight different primary myelodysplastic syndromes, based on the number of dysplastic cell lines and the percentage of blasts in the bone marrow, among other criteria
  • The most common types are refractory cytopenia with multilineage dysplasia, refractory anemia with ringed sideroblasts, and refractory cytopenia with unilineage dysplasia


Clinical features





The therapeutic approach depends on a patient's presentation, age, and comorbidities. More aggressive therapy (e.g., chemotherapy, stem cell transplantation) is generally reserved for younger, healthier patients.



Depending on the chromosomal aberrations detected in pluripotent stem cells, up to 30% of MDS cases may progress to acute myelogenous leukemia.


We list the most important complications. The selection is not exhaustive.