The International Prognostic Scoring System is another tool for determining the prognosis of MDS, published in Blood in 1997. This system takes into account the percentage of blasts in the marrow, cytogenetics, and number of cytopenias. Genetic markers
Although not yet formally incorporated in the generally accepted classification systems, molecular profiling of myelodysplastic syndrome genomes has increased the understanding of prognostic molecular factors for this disease. For example, in low-risk MDS, IDH1 and IDH2 mutations are associated with significantly worsened survival. Epidemiology
The exact number of people with MDS is not known because it can go undiagnosed and no tracking of the syndrome is mandated. Some estimates are on the order of 10,000 to 20,000 new cases each year in the United States alone. The number of new cases each year is probably increasing as the average age of the population increases, and some authors propose that the number of new cases in those over 70 may be as high as 15 per 100,000 per year.The typical age at diagnosis of MDS is between 60 and 75 years; a few people are younger than 50, and diagnoses are rare in children. Males are slightly more commonly affected than females. History
Since the early 20th century, some people with acute myelogenous leukemia were begun to be recognized to have a preceding period of anemia and abnormal blood cell production. These conditions were lumped together with other diseases under the term "refractory anemia". The first description of "preleukemia" as a specific entity was published in 1953 by Block et al.
less than 40 years of age) and more severely affected patients, offers the potential for curative therapy. The success of bone marrow transplantation has been found to correlate with severity of MDS as determined by the IPSS score, with patients having a more favorable IPSS score tend to have a more favorable outcome with transplantation. Iron levels
Iron overload can develop in MDS as a result of the RBC transfusions, which are a major part of the supportive care for anemic MDS patients. Although the specific therapies patients receive may alleviate the RBC transfusion need in some cases, many MDS patients may not respond to these treatments, thus may develop secondary hemochromatosis due to iron overload from repeated RBC transfusions. Patients requiring relatively large numbers of RBC transfusions can experience the adverse effect of chronic iron overload on their liver, heart, and endocrine functions. For patients requiring many RBC transfusions, serum ferritin levels, number of RBC transfusions received, and associated organ dysfunction (heart, liver, and pancreas) should be monitored to determine iron levels. Monitoring serum ferritin may also be useful, aiming to decrease ferritin levels to < 1000 µg/L.Currently, two iron chelators are available in the US, deferoxamine for intravenous use and deferasirox for oral use. These options now provide potentially useful drugs for treating the iron overload problem.