Current challenges in therapy of myelodysplastic syndromes.
The International Prognostic Scoring System (or, more conveniently, the marrow blast percentage) can be used to divide patients with myelodysplasia into those with better (International Prognostic Scoring System low/ intermediate-1, or <10% blasts) and worse (International Prognostic Scoring System intermediate-2/high, or >10% blasts) prognoses. There is no treatment known to produce responses in the great majority of patients in either group. Hence, most patients should be considered for clinical trials. Exceptions are cases with low serum erythropoietin levels or low marrow cellularity; such cases may benefit from erythropoietin with or without granulocyte colony-stimulating factor or antithymocyte globulin, respectively. A wide variety of new agents are in clinical trial. These can be grouped into biologic or targeted, therapies, acute myelogenous leukemia-type chemotherapy, and allogeneic stem cell transplants. In general, competing risk-to-benefit ratios and consideration of natural histories suggest that patients with a better prognosis should receive biologic therapies first, with transplant reserved until failure. In higher-risk patients, particularly those who are relatively young or have a normal karyotype, acute myelogenous leukemia-type chemotherapy or transplant should be considered earlier in the course. The advent of nonmyeloablative (mini) transplant protocols has extended to 70 to 75 years the age at which transplantation can be performed, although the efficacy of such protocols is unknown. Current data do not permit recommendation of specific regimens in patients with a better or worse prognosis; rather, emphasis should be placed on entry into a clinical trial Finally, because other causes of cytopenias are more treatable, the diagnosis of myelodysplastic syndrome should depend on more than the presence of dysplasia, unless the dysplasia is very severe.
Estey
Elihu H
EH
Department of Leukemia, University of Texas, M.D. Anderson Cancer Center, Houston 77030, USA. ehestey@mdanderson.org
D000465:Algorithms; D000970:Antineoplastic Agents / Q000627:therapeutic use; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000628:therapy*; D011379:Prognosis
D000970:Antineoplastic Agents