Usability of femoral head bone marrow to verify reference ranges for the assessment of myelodysplasia by flow cytometry. (2nd September 2018) - van Gammeren, Adriaan J.
Abstract: Background: A flow cytometry score (FCS) based on four parameters has been proposed for analysis of myelodysplastic syndromes patients with <5% blasts. We evaluated whether bone marrow aspirate samples isolated from femoral heads could be used for verification of cutoff values of the individual parameters score (IPS), contributing to the FCS and compared the applicability of FCS parameters in two centers. Study design and methods: Bone marrow cells were obtained from femoral heads of patients who underwent hip replacement surgery. The score of the 4 individual parameters of the cell samples were obtained independently in two centers, using their own facilities and methods. Flow cytometry data files were subsequently exchanged and reanalyzed in the other center. The resulting four data sets were compared to assess reproducibility and outcomes in both centers. Results: Twenty‐nine of 40 bone marrow samples contained sufficient cells for analysis. Proposed cutoff values for 3 of 4 individual parameters were appropriate. All 29 samples showed a positive individual parameters score (IPS:1) in 1 of the 4 obtained data sets. Most differences in IPS scores were a result of reanalyzing the data file in the other center, rather than data acquisition. FCS: ≥2 were observed in 11 samples. Conclusion: Bone marrow samples from femoral heads are appropriate for verification of the proposed reference cutoff values of the individual parameters. Proposed reference cutoff values needed to be adjusted for reliable interpretation. Standardization of both data acquisition and data analysis is necessary for obtaining uniform results.