Classification and prognostic evaluation of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are myeloid neoplasms characterized by dysplasia in one or more cell lines and increased risk of development of acute myeloid leukemia (AML). The current diagnostic approach to MDS includes peripheral blood and bone marrow morphology to evaluate abnormalities of peripheral blood cells and hematopoietic precursors; bone marrow biopsy to assess marrow cellularity, fibrosis, and topography; and cytogenetics to identify non-random chromosomal abnormalities. The 2008 World Health Organization (WHO) classification currently provides the best diagnostic approach to MDS and also has considerable prognostic relevance. The WHO classification-based prognostic scoring system (WPSS) is able to classify MDS patients into five risk groups showing different survivals and probabilities of leukemic evolution. The WPSS is able to predict survival and leukemia progression at any time during follow-up, and can therefore be used for implementing risk-adapted treatment strategies in patients with primary MDS. Since comorbidities have a significant impact on the outcome of patients with MDS, accounting for both disease status and comorbid conditions considerably improves risk stratification.