Myelodysplastic and Myeloproliferative Neoplasms: Updates On The Overlap Syndromes

Abstract

ABSTRACT Background: Myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are disorders of the hematopoietic stem cell as well as evolved entities which have characters of both myelodysplastic syndrome and myeloproliferative neoplasms resulting in difficulty in diagnosis. Chronic myelomonocytic leukaemia (CMML), juvenile myelomonocytic leukaemia (JMML), atypical chronic myeloid leukaemia (aCML), MDS / MPN-unclassifiable (MDS / MPNU) and MDS / MPN with ring sideroblasts and thrombocytosis (MDS / MPN-RS-T) are encompassed in the 2016 MDS / MPN classification system (WHO). Each type of MDS/MPN has its specific characteristic feature such as increased number of monocyte in CMML, prominent dysplasia in granulocytic lineage in aCML, and increase platelet count in MDS/MPN-RS-T.Multiple molecular techniques are used in diagnosis, follow up, and prognosis of hematological malignancy. These techniques are used for the detection of molecular and cytogenetic abnormalities. They include conventional karyotyping, fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH), polymerase chain reaction (PCR), next-generation sequencing (NGS) technology, and nanopore sequencing. Recent techniques as Next generation sequencing (NGS) studies helps in identification of various genetic pathways and somatic mutation. Adding the molecular findings to pathomorphologic characters has raised the accuracy of diagnosis in MDS/MPN. Objective: to give new trends in diagnosis of myelodysplastic/myeloproliferative neoplasms. Conclusion: MDS/MPN has overlapping features of both MDS and MPN, which further make it difficult in diagnosis. New molecular techniques such as NGS and nanopore sequencing, detect all types of genetic abnormalities and improve the diagnosis of MDS/MPN.