Myelodysplastic Syndromes / Myeloproliferative Disorders
What are myelodysplastic syndromes? Myelodysplastic syndromes are clonal marrow stem-cell disorders, characterized by ineffective hemopoiesis leading to blood cytopenias, and by progression to acute myeloid leukemia in a third of patients. Who is affected? 15% of cases occur after chemotherapy or radiotherapy for a previous cancer. The syndromes are most common in elderly people. What is the cause? The pathophysiology involves cytogenetic changes with or without gene mutations and widespread gene hypermethylation at advanced stages. What are the symptoms? Clinical manifestations result from cytopenias (anemia, infection, and bleeding). How to make the diagnosis? Diagnosis is based on examination of blood and bone marrow showing blood cytopenias and hypercellular marrow with dysplasia, with or without excess of blasts. Prognosis depends largely on the marrow blast percentage, number and extent of cytopenias, and cytogenetic abnormalities. What is the treatment? Treatment of patients wit...