Background: Myelodysplastic syndrome (MDS) is occasionally accompanied by bone marrow (BM) eosinophilia or basophilia. This study investigated molecular and cytogenetic characteristics and clinical implications of MDS with BM eosinophilia or basophili...
Background: Myelodysplastic syndrome (MDS) is occasionally accompanied by bone marrow (BM) eosinophilia or basophilia. This study investigated molecular and cytogenetic characteristics and clinical implications of MDS with BM eosinophilia or basophilia as well as their prevalence.
Methods: A total of 464 MDS patients were evaluated for prevalence of BM eosinophilia or basophilia. A total of 74 MDS patients were included in the next-generation sequencing (NGS) testing, which was conducted on 90 candidate genes frequently found in hematologic malignancies. Fourteen patients exhibited BM eosinophilia (MDS-EOS), six patients displayed BM basophilia (MDS-BASO), fifty-five patients did not demonstrate eosinophilia or basophilia (MDS-/-), and only one satisfied both MDS-EOS and MDS-BASO. Cytogenetic abnormalities and overall survival were also investigated.
Results: MDS with BM eosinophilia or basophilia were observed in 7.33% or 4.09% of patients, respectively. MDS-EOS revealed significantly higher frequencies of mutations in ATM, TP53, CEBPA, FLT3 and DNA damage response (DDR) genes (ATM, PPM1D and TP53 combined). In MDS-BASO, significantly higher frequencies of mutations in ASXL1 and U2AF1 were shown. Variant allele frequency of DDR gene mutations significantly correlated with increased BM eosinophil fraction. Significant frequencies of abnormalities involving chromosomes 5 and 7 and of complex chromosomal abnormalities were found in both MDS-EOS and MDS-BASO. MDS-EOS demonstrated significantly poorer survival rates than MDS-/-.
Conclusion: MDS with BM eosinophilia or basophilia was not uncommon. MDS with BM eosinophilia exhibited distinct mutational profiles including DDR gene mutations, which may attribute to adverse clinical outcomes. Identification of these subtypes can aid in prognosis and potentially guide targeted therapeutic approaches.