8 research outputs found
The feasibility and efficacy of subcutaneous plerixafor for mobilization of peripheral blood stem cells in allogeneic HLA–identical sibling donors: results of the HOVON-107 study
Background: Plerixafor (PFX) mobilizes CD34+ cells into circulation by disrupting the CXCR4 binding of the hematopoietic stem cell in its bone marr
Immunophenotypic measurable residual disease (MRD) in acute myeloid leukemia: Is multicentric MRD assessment feasible?
Flow-cytometric detection of now termed measurable residual disease (MRD) in acute myeloid leukemia (AML) has proven to have an independent prognostic impact. In a previous multicenter study we developed protocols to accurately define leukemia-associated immunophenotypes (LAIPs) at diagnosis. It has, however, not been demonstrated whether the use of the defined LAIPs in the same multicenter setting results in a high concordance between centers in MRD assessment. In the present paper we evaluated whether interpretation of list-mode data (LMD) files, obtained from MRD assessment of previously determined LAIPs during and after treatment, could reliably be performed in a multicenter setting. The percentage of MRD positive cells was simultaneously determined in totally 173 LMD files from 77 AML patients by six participating centers. The quantitative concordance between the six participating centers was meanly 84%, with slight variation of 75%–89%. In addition our data showed that the type and number of LAIPs were of influence on the performance outcome. The highest concordance was observed for LAIPs with cross-lineage expression, followed by LAIPs with an asynchronous antigen expression. Our results imply that immunophenotypic MRD assessment in AML will only be feasible when fully standardized methods are used for reliable multicenter assessment
Complete remission of t(11;17) positive acute promyelocytic leukemia induced by all-trans retinoic acid and granulocyte colony-stimulating factor
The combined use of retinoic acid and chemotherapy has led to an important
improvement of cure rates in acute promyelocytic leukemia. Retinoic acid
forces terminal maturation of the malignant cells and this application
represents the first generally accepted differentiation-based therapy in
leukemia. Unfortunately, similar approaches have failed in other types of
hematological malignancies suggesting that the applicability is limited to
this specific subgroup of patients. This has been endorsed by the
notorious lack of response in acute promyelocytic leukemia bearing the
variant t(11;17) translocation. Based on the reported synergistic effects
of retinoic acid and the hematopoietic growth factor granulocyte
colony-stimulating factor (G-CSF), we studied maturation of t(11;17)
positive leukemia cells using several combinations of retinoic acid and
growth factors. In cultures with retinoic acid or G-CSF the leukemic cells
did not differentiate into mature granulocytes, but striking granulocytic
differentiation occurred with the combination of both agents. At relapse,
the patient was treate
High EVI1 expression predicts poor survival in acute myeloid leukemia: a study of 319 de novo AML patients
The proto-oncogene EVI1 encodes a DNA binding protein and is located on
chromosome 3q26. The gene is aberrantly expressed in acute myeloid
leukemia (AML) patients carrying 3q26 abnormalities. Two mRNAs are
transcribed from this locus: EVI1 and a fusion of EVI1 with MDS1
(MDS1-EVI1), a gene located 5' of EVI1. The purpose of this study was to
investigate which of the 2 gene products is involved in transformation in
human AML. To discriminate between EVI1 and MDS1-EVI1 transcripts,
distinct real-time quantitative polymerase chain reaction (PCR) assays
were developed. Patients with 3q26 abnormalities often showed high EVI1
and MDS1-EVI1 expression. In a cohort of 319 AML patients, 4 subgroups
could be distinguished: EVI1(+) and MDS1-EVI1(-) (6 patients; group I),
EVI1(+) and MDS1-EVI1(+) (26 patients; group II), EVI1(-) and MDS1-EVI1(+)
(12 patients; group III), and EVI1(-) and MDS1-EVI1(-) (275 patients;
group IV). The only 4 patients with a 3q26 aberration belonged to groups I
and II. Interestingly, high EVI1 and not MDS1-EVI1 expression was
associated with unfavorable karyotypes (eg, -7/7q-) or complex karyotypes.
Moreover, a significant correlation was observed between EVI1 expression
and 11q23 aberrations (mixed lineage leukemia [MLL] gene involvement).
Patients from groups I and II had significantly shorter overall and
event-free survival than patients in groups III and IV. Our data
demonstrate that high EVI1 expression is an independent poor prognostic
marker within the intermediate- risk karyotypic group
Transfusion of pooled buffy coat platelet components prepared with photochemical pathogen inactivation treatment: the euroSPRITE trial
A nucleic acid-targeted photochemical treatment (PCT) using amotosalen HCl (S-59) and ultraviolet A (UVA) light was developed to inactivate viruses, bacteria, protozoa, and leukocytes in platelet components. We conducted a controlled, randomized, double-blinded trial in thrombocytopenic patients requiring repeated platelet transfusions for up to 56 days of support to evaluate the therapeutic efficacy and safety of platelet components prepared with the buffy coat method using this pathogen inactivation process. A total of 103 patients received one or more transfusions of either PCT test (311 transfusions) or conventional reference (256 transfusions) pooled, leukoreduced platelet components stored for up to 5 days before transfusion. More than 50% of the PCT platelet components were stored for 4 to 5 days prior to transfusion. The mean 1-hour corrected count increment for up to the first 8 test and reference transfusions was not statistically significantly different between treatment groups (13,100 +/- 5400 vs 14,900 +/- 6200, P =.11). By longitudinal regression analysis for all transfusions, equal doses of test and reference components did not differ significantly with respect to the 1-hour (95% confidence interval [CI], -3.1 to 6.1 x 10(9)/L, P =.53) and 24-hour (95% CI, -1.3 to 6.5 x 10(9)/L, P =.19) posttransfusion platelet count. Platelet transfusion dose, pretransfusion storage duration, and patient size were significant covariates (P <.001) for posttransfusion platelet counts. Clinical hemostasis, hemorrhagic adverse events, and overall adverse events were not different between the treatment groups. Platelet components prepared with PCT offer the potential to further improve the safety of platelet transfusion using technology compatible with current methods to prepare buffy coat platelet components
Implementation of erythroid lineage analysis by flow cytometry in diagnostic models for myelodysplastic syndromes
Flow cytometric analysis is a recommended tool in the diagnosis of myelodysplastic syndromes. Current flow cytometric approaches evaluate the (im)mature myelo-/monocytic lineage with a median sensitivity and specificity of ~71% and ~93%, respectively. We hypothesized that the addition of erythroid lineage analysis could increase the sensitivity of flow cytometry. Hereto, we validated the analysis of erythroid lineage parameters recommended by the International/European LeukemiaNet Working Group for Flow Cytometry in Myelodysplastic Syndromes, and incorporated this evaluation in currently applied flow cytometric models. One hundred and sixty-seven bone marrow aspirates
Implementation of erythroid lineage analysis by flow cytometry in diagnostic models for myelodysplastic syndromes
Flow cytometric analysis is a recommended tool in the diagnosis of myelodysplastic syndromes. Current flow cytometric approaches evaluate the (im)mature myelo-/monocytic lineage with a median sensitivity and specificity of ~71% and ~93%, respectively. We hypothesized that the addition of erythroid lineage analysis could increase the sensitivity of flow cytometry. Hereto, we validated the analysis of erythroid lineage parameters recommended by the International/European LeukemiaNet Working Group for Flow Cytometry in Myelodysplastic Syndromes, and incorporated this evaluation in currently applied flow cytometric models. One hundred and sixty-seven bone marrow aspirates were analyzed; 106 patients with myelodysplastic syndromes, and 61 cytopenic controls. There was a strong correlation between presence of erythroid aberrancies assessed by flow cytometry and the diagnosis of myelodysplastic syndromes when validating the previously described erythroid evaluation. Furthermore, addition of erythroid aberrancies to two different flow cytometric models led to an increased sensitivity in detecting myelodysplastic syndromes: from 74% to 86% for the addition to the diagnostic score designed by Ogata and colleagues, and from 69% to 80% for the addition to the integrated flow cytometric score for myelodysplastic syndromes, designed by our group. In both models the specificity was unaffected. The high sensitivity and specificity of flow cytometry in the detection of myelodysplastic syndromes illustrates the important value of flow cytometry in a standardized diagnostic approach
Addition of bevacizumab to chemotherapy in acute myeloid leukemia at older age: A randomized phase 2 trial of the Dutch-Belgian Cooperative Trial Group for Hemato-Oncology (HOVON) and the Swiss Group for Clinical Cancer Research (SAKK)
An urgent need for new treatment modalities is emerging in elderly patients with acute myeloid leukemia (AML). We hypothesized that targeting VEGF might furnish an effective treatment modality in this population. Elderly patients with AML were randomly assigned in this phase 2 study (n = 171) to receive standard chemotherapy (3 + 7) with or without bevacizumab at a dose of 10 mg/kg intravenously at days 1 and 15. In the second cycle, patients received cytarabine 1000 mg/m2 twice daily on days 1-6 with or without bevacizumab. The complete remission rates in the 2 arms were not different (65%). Event-free survival at 12 months was 33% for the standard arm versus 30% for the bevacizumab arm; at 24 months, it was 22% and 16%, respectively (P = .42). The frequencies of severe adverse events (SAEs) were higher in the bevacizumab arm (n = 63) compared with the control arm (n = 28; P = .043), but the percentages of death or life-threatening SAEs were lower in the bevacizumab arm (60% vs 75% of SAEs). The results of the present study show that the addition of bevacizumab to standard chemotherapy does not improve the therapeutic outcome of older AML patients. This trial is registered as number NTR904 in The Nederlands Trial Register (www.trialregister.nl)