Validity of new flow cytometric protocol in diagnosis of low-grade myelodysplastic syndromes
B Jamoh Yusuf1, P Goggolidou2, T Milne3, AA Abba1, AG Bakari1, A Sa'idu4, AI Dutse5, BA Gwaram5, K Ashfaq6, SA Abubakar1
1 Department of Medicine, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria
2 School of Life Sciences, Kingston University, London, UK
3 Department of Haemato-Oncology, King's Path, King's College Hospital, London, UK
4 Department of Medicine, Federal Medical Center, Gombe, Nigeria
5 Department of Medicine, Aminu Kano Teaching Hospital, Kano, Nigeria
6 Centre for Clinical Practice, National Institute of Health and Clinical Excellence MidCity Place, London, UK
B Jamoh Yusuf
Department of Medicine, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria
Source of Support: The authors did not receive any form of support from any
source., Conflict of Interest: The authors declare that they have no conflict
of interest in this study.
Background: Myelodysplastic syndromes (MDS) are the most common of myeloid malignancies, yet the morphological diagnosis is usually not straightforward especially in the low-grade forms. Immunophenotyping by Flow cytometry (FCM) is considered essential in the WHO's co-criteria for diagnosis of MDS. The Existing FCM Protocol utilizes a two-tube, two-colour approach to identify lineage specific cluster of differentiation (CD) markers, which is labour-intensive and time-consuming. A new FCM was recently developed and validated among Japanese cohorts. It utilizes a three-tube, five-colour approach and generates more information in the form of 'cardinal parameters'. The aim of this study is to determine the diagnostic utility of the new protocol by comparing it with the existing protocol, in the diagnosis of low-grade MDS in our study population. Materials and Methods: We analyzed bone marrow samples of 30 subjects at King's, London. They comprised of 27 patients who had a tentative diagnosis of MDS and three healthy bone marrow donors as controls. Immunophenotyping by FCM was performed using the Existing and New Protocols and the data obtained by the two different methods were compared. 'Cardinal parameters' were generated in the new protocol, which are not applicable to the existing protocol. Results: There was no statistical difference between the data generated by the two protocols in the diagnosis of MDS. The sensitivity and specificity of the 'cardinal parameters' of the new protocol appeared to be outstanding. Conclusion: It has been shown that the new multiplex FCM protocol for the diagnosis of MDS is relatively easy, cost effective and not inferior, compared to the Existing Protocol. However, small sample size has been identified as a limitation to the study and therefore a larger, multicenter study is recommended to assess this validation exercise.