Treatment of low-risk myelodysplastic syndromes

The majority of myelodysplastic syndrome (MDS) patients belong to the International Prognostic Scoring System (IPSS) and IPSS-revised (IPSS-R) lower-risk categories. Their precise diagnostics and prognostic stratification is often a challenge, but may ensure the optimization of therapy. The availability of diverse treatment options has significantly improved the quality of life and survival of this group of patients. Anemia is the most relevant cytopenia in terms of frequency and symptoms in lower-risk MDS, and may be treated successfully with erythropoietic stimulating agents, provided a careful selection is performed on the basis of IPSS-R, endogenous erythropoietin levels, and transfusion independence. Doses and duration of therapy of erythropoietic-stimulating agents (ESAs) are critical to determine efficacy. In case a patient fails ESA treatment, the available options may include lenalidomide (approved for del5q positive cases), hypomethylating agents, and a rather large number of experimental agents, whose clinical trials should be offered to a larger number of MDS patients. The choice for second-line treatment must take into account biologic, cytogenetic, and molecular-identified characteristics of individual patients, as well as frailty and comorbidities. Other cytopenias are less frequently presenting as isolated. Specific therapy for thrombocytopenia has been proposed in experimental clinical trials with thrombomimetic agents that have shown good efficacy, but raised some safety concern. Although neutropenia is targeted symptomatically with growth factor supportive care, the immunosuppressive treatments are indicated mainly for pancytopenic, hypoplastic lower-risk MDS; they are not widely used because of their toxicity, despite the fact that they may induce responses. Finally, hematopoietic stem cell transplant is the curative option also for lower-risk MDS and timing should be carefully evaluated, balancing toxicity and the possibility of survival advantage. Finally, even when considered suitable for lower-risk MDS, transplant application is limited to the rarer fit and younger MDS patient.