Genomic diversity in myeloproliferative neoplasms: focus on myelofibrosis

The classical myeloproliferative neoplasms (MPNs) are a group of clonal diseases comprising essential thrombocythaemia (ET), polycythaemia vera (PV) and primary myelofibrosis (PMF). PMF is the rarest disease sub type and has been challenging to address due to the lack of a specific genetic marker, inadequate risk identification models and a highly variable clinical course. Continuous efforts have over time, seen the inclusion of cytogenetic information in prognostic scoring models that have resulted in improved risk stratification models providing further rationale for therapeutic management. Technological advances using single nucleotide polymorphism arrays increased the detection of known and novel MPN related changes and variant detection by massively parallel sequencing provided a large scale screening tool for the multitude of somatic gene mutations that have more recently been described in MPN. Some of these mutations show an association with specific cytogenetic changes or phenotypes. While PMF occurs mainly in adults, it has also been described in paediatric cases and shows distinct histopathological, genetic and clinical features in comparison. This review provides an overview of the genomics landscape of PMF and current developments in MPN therapy.