Molecular Testing in Myelodysplastic Syndromes for the Practicing Oncologist: Will the Progress Fulfill the Promise?

Myelodysplastic syndromes (MDS) are heterogeneous hematopoietic neoplasms that are driven by somatically acquired genetic mutations and epigenetic alterations. Accurate risk stratification is essential for delivery of risk-adaptive therapeutic interventions. The current prognostic tools sum the impact of clinical, pathologic, and laboratory parameters. Newer technologies with next-generation targeted deep sequencing and whole-genome and -exome sequencing have identified several recurrent mutations that play a vital role in the pathophysiology of MDS and the impact of these genetic changes on disease phenotype. Equally important, well-annotated databases of MDS patients with paired clinicopathologic and genetic data have enabled better understanding of the independent prognostic impact of several molecular mutations on important clinical endpoints such as overall survival and probability of leukemic progression. Cumulative evidence suggests that genomic data can also be used clinically to aid with the diagnosis, prognosis, prediction of response to specific therapies, and the development of novel and rationally targeted therapies. However, the optimal use of this mutational profiling remains a work in progress and currently there is no standard set of genes or techniques that are recommended for routine use in the clinic. In this review, we discuss the genomic revolution and its impact on our understanding of MDS biology and risk stratification. We also discuss the current role and the challenges of the application of genetic mutational data into daily clinical practice and how future research could help improve the prognostication precision and specific therapy selection for patients with MDS.

Implications for practice: Heterogeneity in clinical outcomes of MDS is partly related to interpatient variability of recurrent somatic mutations that drive disease phenotype and progression. Although clinical risk stratification tools have functioned well in prognostication for patients with MDS, their ability to predict clinical benefits of specific MDS therapies is limited. Molecular testing shows promise in aiding diagnosis, risk stratification, and therapy-specific benefit prediction for MDS patients. Nonetheless, logistical issues related to assay performance standardization, validation, interpretation, and development of guidelines for how to use the results to inform clinical decisions are yet to be resolved.