Platelet Defects in Acute Myeloid Leukemia-Potential for Hemorrhagic Events.

BACKGROUND AND OBJECTIVES: In acute myeloid leukemia (AML), extensive bleeding is one of the most frequent causes of death. Impaired activation and aggregation processes were identified in previous studies on platelet behaviour associated with this disease. This study's aim was to examine platelet function in correlation with other haemorrhage risk factors (fever, sepsis, recent bleeding, uraemia, leucocytosis, haematocrit value, treatment). DESIGN AND METHODS: The analysis of platelet surface proteins (Glycoprotein Ib-IX (CD42b, CD42a), Glycoprotein IIb-IIIa (CD41, CD61), p-selectin (CD62P), granulophysin (CD63)) was conducted by flowcytometry from samples of whole blood in patients with acute myeloid leukaemia in different stages of diagnosis and therapy (n = 22) in comparison with healthy human controls (n = 10). RESULTS AND INTERPRETATIONS: Our results show a significant decrease in fluorescence level associated with platelet activation markers (CD63 (14.11% vs. 40.78 % p < 0.05); CD62P (15.26% vs. 28.23% p < 0.05)); adhesion markers (CD42b (69.08% vs. 84.41% p < 0.05)) and aggregation markers (CD61 (83.79% vs. 98.62% p < 0.001)) in patients compared to controls. The levels of CD41 (80.62% vs. 86.31%, p = 0.290) and CD42a (77.98% vs. 94.15%, p = 0.99) demonstrate no significant differences in the two groups. CONCLUSION: The AML patients present changes in adhesion receptors and activation markers, suggesting a functional defect or denatured intracellular signalling in platelets. The exposed data indicate that flow cytometry can effectively identify multiple functional platelet impairments in AML pathogenesis.

Post-Essential Thrombocythemia Myelofibrosis and Multiple Isodicentric Y Chromosomes: A Unique Case among a Rare Association.

Multiple isodicentric Y chromosomes [idic(Y)] is a rare cytogenetic abnormality, most exclusively described in constitutional karyotypes. Only recently has this entity been reported in hematologic neoplasms such as myeloid disorders, albeit these cases remain very scarce. The possible involvement of increasing copies of potential proto-oncogenes located on the multiple idic(Y) led to consider one of them, CRLF2, as a target for kinase inhibitors. We report here, to our knowledge, the first case of multiple idic(Y) in a patient with myelofibrosis secondary to essential thrombocythemia. The patient received ruxolitinib therapy with initial good clinical response.

Interferon alpha with or without rituximab achieves a high response rate and durable responses in relapsed FL: 17 years' experience in a single centre.

Maintenance interferon alpha (IFN-α) immunotherapy after induction chemotherapy prolongs progression-free survival (PFS) in untreated follicular lymphoma (FL). Little information is available about IFN-α use in relapsed FL. This study aims to evaluate the benefit of IFN-α as a treatment of low-burden FL relapse. This single-centre retrospective study identified 20 patients treated in 27 cases with IFN-α. We analysed all cases of IFN-α treatment in patients with low-burden FL in clinical relapse (11), partial response (5) or only with molecular minimal residual disease (MRD; 5). The treatment schedule was 3MIU IFN-α three times a week alone (16) or combined with four weekly rituximab (R; 11), according to the institution's policy. Except for the molecular relapses, responses were evaluated according to the IWG 1999 criteria. MRD was defined as a repeatedly detectable BCL2-IgH rearrangement in peripheral blood or bone marrow. In 22 cases of clinical relapses or partial responders, overall response rate was 68 %, with 55 % complete responses. Median PFS was 20.9 months (95 % confidence interval (95 % CI), 0-64.9) with 20.9 and 48.7 months in the IFN and R-IFN groups, respectively (p = 0.4). The median PFS of the five MRD cases was 133 months (95 % CI, 103-165). The Follicular Lymphoma International Prognostic Index score calculated at initiation of IFN-α treatment was predictive of time to relapse (p = 0.036). These results compare favourably with previous reports of the efficacy of R alone, and of R with IFN-α in relapse. Further research is required to explore the role of IFN-α in the management of FL.