Search

Transformation of myelodysplastic syndrome (MDS) into acute myelogenous leukemia occurs in approximately 30 % of cases, while progression into acute lymphoblastic leukemia (ALL) is rare. We report on a 67-year-old man with the diagnosis of MDS, subtype refractory anemia with ring sideroblasts (RARS), karyotype 20q- , JAK-2 negative and grade III fibrosis on the bone marrow biopsy, who evolved into ALL 33 months after the diagnosis of MDS. RARS is one of the subtypes of MDS with most indolent course. Deletion of the long arm of chromosome 20 (20q-) is considered as good prognosis by the International Prognostic Scoring System, an important scoring system for predicting survival and evolution of MDS. Primary MDS with bone marrow fibrosis may represent a distinct clinicopathological and is supposed to have an unfavorable prognosis. The combined analysis of these features makes this rare report still more challenging and illustrates that biology of MDS is yet to be discovered.

Dendritic cells (DC) are pivotal for T cell-mediated immunity. We investigated the early and terminal maturation of monocyte-derived DC (MoDC) in myelodysplastic syndromes (FAB subtypes refractory anemia (MDS-RA) or refractory anemia with ringed sideroblasts (MDS-RARS)). Immature MoDC were obtained by culture of monocytes with GM-CSF and IL-4 for 8 days. To obtain mature MoDC, TNF-alpha was added during the final three culture days. T cell proliferation and T cell cytokine secretion in mixed lymphocyte reactions (MLR) unveiled a strong reduction of allostimulatory capacity of mature but also of immature MoDC from MDS patients. Immature MoDC from MDS patients exhibited an almost normal immunophenotype, but secreted substantially less IL-12 and more IL-10 in response to LPS/IFN-gamma than normal controls. Terminal addition of TNF-alpha to GM-CSF/IL-4 treated monocytes failed to extinguish cytokine production by MDS MoDC and failed to induce the expected membrane upregulation of costimulatory and other ligands as in normal controls. While our data provide further support for previous studies that have indicated an impaired differentiation of immature towards mature MoDC, they also clearly demonstrate a qualitatively and quantitatively altered cytokine secretion at the level of immature MoDC, which may in part explain the reduced allostimulatory capacity of these cells. These alterations may contribute to immune modulation of the clinical phenotype of marrow failure in MDS, and may have to be considered when designing DC-based immunotherapeutic strategies for MDS.

34 patients with primary myelodysplastic syndrome (MDS), initially diagnosed as subtypes refractory anaemia (RA) and RA with ringed sideroblasts (RA-S), were followed to investigate the distribution of lymphoid and myeloid differentiation antigens in the blood and bone marrow in search of potential prognostic significance with regard to progression to RA with an excess of blasts (RAEB) or acute myeloid leukaemia, and for relations to clinical, morphological and cytogenetic findings. Patients who later progressed to RAEB had significantly decreased percentages of anti-T8 positive T-suppressor cells in the blood at diagnosis compared to those who did not (p = 0.05). Sequential analysis showed a decrease with time also in the percentages of anti-T8-positive cells (p = 0.05). In the bone marrow, progressing patients initially showed significantly increased percentages of anti-My9-positive immature myeloid cells (p less than 0.001), and the percentages of anti-My9-positive cells in the bone marrow increased with time (p less than 0.005). Analysis of the pooled data revealed a statistically significant relation between increasing percentages of anti-My9-positive cells and the frequencies of clonally abnormal (p less than 0.001) and abnormal (p = 0.004) metaphases.