Severe idiopathic erythroblastic synartesis: successful treatment with the anti-CD20 monoclonal antibody rituximab.

Erythroblastic synartesis is a very rare disorder, considered to be caused by autoimmune mechanisms, leading to aggregation of erythroid precursor cells in the bone marrow and subsequently to acquired dyserythropoiesis with severe, transfusion-dependent anemia. An association with lymphoproliferative or autoimmune diseases has been reported or strongly suggested in all six published cases. Here, we report a young patient with severe idiopathic erythroblastic synartesis without an underlying disease, who was successfully treated with rituximab, an anti-CD20 monoclonal antibody. The patient received rituximab at a dose of 375 mg/m(2) once weekly for 4 wk after failure of both immunosuppressive therapies with corticosteroids and intravenous immunoglobulins. At a follow-up of 30 months after treatment, the patient is still in continuous complete remission without any further treatment, suggesting that rituximab may induce prolonged remissions and eventually cure in this rare disease.

Microarray-based classifiers and prognosis models identify subgroups with distinct clinical outcomes and high risk of AML transformation of myelodysplastic syndrome.

The diagnosis of myelodysplastic syndrome (MDS) currently relies primarily on the morphologic assessment of the patient's bone marrow and peripheral blood cells. Moreover, prognostic scoring systems rely on observer-dependent assessments of blast percentage and dysplasia. Gene expression profiling could enhance current diagnostic and prognostic systems by providing a set of standardized, objective gene signatures. Within the Microarray Innovations in LEukemia study, a diagnostic classification model was investigated to distinguish the distinct subclasses of pediatric and adult leukemia, as well as MDS. Overall, the accuracy of the diagnostic classification model for subtyping leukemia was approximately 93%, but this was not reflected for the MDS samples giving only approximately 50% accuracy. Discordant samples of MDS were classified either into acute myeloid leukemia (AML) or "none-of-the-targets" (neither leukemia nor MDS) categories. To clarify the discordant results, all submitted 174 MDS samples were externally reviewed, although this did not improve the molecular classification results. However, a significant correlation was noted between the AML and "none-of-the-targets" categories and prognosis, leading to a prognostic classification model to predict for time-dependent probability of leukemic transformation. The prognostic classification model accurately discriminated patients with a rapid transformation to AML within 18 months from those with more indolent disease.