MDS classification is improving in an era of the WHO 2016 criteria of MDS: A population-based analysis among 9159 MDS patients diagnosed in the Netherlands

- The proportion of unclassified MDS decreased from 58% in 2001 to 13% in 2014.
- The degree of dysplasia was reported in ∼30% of all evaluable bone marrow aspirates.
- Cytogenetic assessment at diagnosis was performed in 54% of patients.
- The IPSS was undetermined in 55% of patients, mainly due to lack of cytogenetics.
- Population-based registries are useful instruments to assess guideline adherence.

BackgroundMorphologic and cytogenetic assessments are required to characterize diagnostic and prognostic features of myelodysplastic syndromes (MDS). We assessed whether these assessments were performed among newly diagnosed MDS patients in the Netherlands.MethodsMDS cases were retrieved from the nationwide Netherlands Cancer Registry (N = 9159; period 2001-2014) and the regional PHAROS MDS registry (N = 676; period 2008-2011).ResultsThe proportion of unclassified MDS decreased from 58% in 2001 to 13% in 2014. Data from the more detailed PHAROS registry revealed that the degree of bone marrow dysplasia was only reported in ∼30% of all evaluable bone marrow aspirates. Further, the International Prognostic Scoring System was undetermined in 55% of patients, primarily owing to unperformed cytogenetics in 46% of patients.ConclusionThe classification of MDS is improving in the Netherlands. Nevertheless, particular diagnostic and prognostic procedures that are essential for the diagnosis and subsequent treatment decision-making of MDS were not fully utilized in particular patient subsets.