Clinical spectrum, outcome and management of immune thrombocytopenia associated with myelodysplastic syndromes and chronic myelomonocytic leukemia

Myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML) are associated with systemic inflammatory or autoimmune diseases in 10-20% of cases. Immune thrombocytopenia (ITP) is among the reportedly associated diseases, but large studies assessing the association are lacking. It is unclear whether patients with MDS or CMML and ITP have a particular phenotype or require particular management. We, therefore, analyzed the clinical spectrum, outcome and therapeutic management of patients with ITP associated with MDS or CMML, in comparison to: (i) patients with primary ITP without MDS/CMML and (ii) patients with MDS/CMML without ITP. Forty-one patients with MDS/CMML-associated ITP were included, of whom 26 (63%) had chronic ITP, 30 (73%) had low-risk myelodysplasia and 24 (59%) had CMML. An associated autoimmune disease was noted in ten (24%) patients. In comparison to patients with primary ITP, patients with MDS/CMML-associated ITP had a higher rate of severe bleeding despite similar platelet counts at diagnosis. First-line treatment consisted of glucocorticoids (98%) and intravenous immunoglobulins (56%). Patients with primary ITP were more likely to respond to intravenous immunoglobulins than were patients with MDS/CMML-associated ITP. Response rates to second-line therapies were not statistically different between patients with primary ITP or MDS/CMML-associated ITP. Four (10%) of the patients with MDS/CMML-associated ITP had multirefractory ITP whereas none of the primary ITP controls did so. After a median follow-up of 60 months, there was no difference in overall survival between patients with MDS/CMML-associated ITP or primary ITP. Leukemia-free-survival was significantly better in patients with MDS/CMML-associated ITP than in those with MDS/CMML without ITP. In conclusion, it appears that patients with MDS/CMML-associated ITP have a particular phenotype, with more severe bleeding than patients with primary ITP, a higher likelihood of multirefractory disease, but a similar response to primary ITP therapy except for intravenous immunoglobulins. Finally, compared to MDS/CMML patients without ITP, they are less likely to progress to having acute myeloid leukemia.