[Diagnosis and therapy strategy in myelodysplastic syndromes]

Myelodysplastic syndromes (MDS) are diagnosed with increasing frequency in recent years. Their crude annual incidence (ca. 4/100,000), is now about twice that of acute myeloid leukemias (AML). In over 70-year-old patients (age-related incidence more than 20/100,000), MDS rival CLL as the most common hematological neoplasias. Diagnosis of MDS is based on cytological and histological examination of bone marrow specimens, which may show various dysplastic features of hematopoietic precursors and an increased percentage of blast cells. In difficult cases the diagnosis of MDS is supported if cytogenetic investigation reveals an abnormal karyotype. Most patients with MDS (60 bis 80%) die from their bone marrow disorder, with infections, hemorrhages and leukemic transformation being the most frequent causes of death. Treatment must take into account the age and general condition of the individual patient as well as the natural course of his MDS. The comparatively favourable prognosis of patients with early-stage MDS should not be jeopardized by therapies carrying a high risk of treatment-related death. Therefore, treatment is often confined to supportive measures (blood transfusions, antibiotics). Patients with increased percentage of blasts, however, have such a poor prognosis that more aggressive approaches including intensive chemotherapy appear justified. Only very few patients can be treated with allogeneic bone marrow transplantation, which offers a chance for cure.