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BackgroundThis report presents a case of an adult Polish women of Caucasian origin who was heterozygous for the nondeletional mutation: Hb Handsworth (HBA2 or HBA1: c.55G > C, p.Gly19Arg) and deletional (-α3.7) α-thalassemia mutation.MethodsThe HbA2 and HbF levels were measured by microcolumn chromatography and alkaline denaturation procedure, respectively, while electrophoresis was used to detect pathological hemoglobin fraction. The β- and α-globin genotypes were determined by DNA sequencing, gap-polymerase chain reaction, α gene triplication and MLPA.ResultsThe HbA2 and HbF levels were normal, but hemoglobin electrophoresis on agarose gel alkaline pH showed a strong band migration in a position of hemoglobin S and faint bands in the neighborhood of band A on acid electrophoresis. Molecular analysis of the alpha globin cluster detected a point mutation at codon 19 in HBA2 (c.55G > C, p.Gl- y19Arg) and deletion -α3.7.ConclusionsOur compound heterozygosity does not produce severe clinical or hematological symptoms but it is important to say that in our part of Europe such cases do appear. Molecular analysis of the alpha globin cluster is required for correct diagnosis in patients with normal HbA2 levels. Compound heterozygosity was unmasked by molecular diagnosis only.

Mutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) genes occur in about 20% patients with acute myeloid leukemia (AML), leading to DNA hypermethylation and epigenetic deregulation. We assessed the prognostic significance of IDH1/2 mutations (IDH1/2+) in 398 AML patients with normal karyotype (NK-AML), treated with daunorubicine + cytarabine (DA), DA + cladribine (DAC), or DA + fludarabine. IDH2 mutation was an independent favorable prognostic factor for 4-year overall survival (OS) in total NK-AML population (p = 0.03, censoring at allotransplant). We next evaluated the effect of addition of cladribine to induction regimen on the patients’ outcome according to IDH1/2 mutation status. In DAC group, 4-year OS was increased in IDH2+ patients, compared to IDH-wild type group (54% vs 33%; p = 0.0087, censoring at allotransplant), while no difference was observed for DA-treated subjects. In multivariate analysis, DAC independently improved the survival of IDH2+ patients (HR = 0.6 [0.37–0.93]; p = 0.024; censored at transplant), indicating that this group specifically benefits from cladribine-containing therapy. In AML cells with R140Q or R172K IDH2 mutations, cladribine restrained mutations-related DNA hypermethylation. Altogether, DAC regimen produces better outcomes in IDH2+ NK-AML patients than DA, and this likely results from the hypomethylating activity of cladribine. Our observations warrant further investigations of induction protocols combining cladribine with IDH1/2 inhibitors in IDH2-mutant.

Autologous hematopoietic stem cell transplantation (autoHSCT) requires collection of sufficient number of hematopoietic stem cells. The goal of this study was to evaluate efficacy of plerixafor used in patients with lymphoid malignancies failing conventional stem cell mobilization.This was a prospective, non-interventional study. All consecutive patients (n = 109) treated with plerixafor in 11 centers were reported. The drug was used either in case of previous mobilization failure (n = 67) or interventionally, in case of insufficient CD34+ cell output during current mobilization (n = 42). Successful mobilization was defined as resulting in collection of ≥ 2 × 106 CD34+ cells/kg for single autoHSCT or ≥ 4 × 106 CD34+ cells/kg for double procedure.The overall rate of successful mobilization was 55% (55% for single and 56% for double autoHSCT). The median total number of collected CD34+ cells/kg was 2.4 (range, 0-11.5) for patients intended for a single transplantation while 4.0 (0.6-16.9) for double procedure. The number of circulating CD34+ cells increased after the use of plerixafor regardless of baseline values. The median fold increase was 3.3 (0.3-155). Data from this observational study confirm high efficacy of plerixafor used in routine clinical practice as salvage for patients with lymphoid malignancies failing conventional stem cell mobilization.

In 23 patients with polycythaemia vera and symptomatic erythrocytosis, glomerular filtration rate and urine concentration ability see article were determined under conditions of antidiuresis. The restriction of fluid intake caused a significant reduction of GFR and modified the osmotic function of the kidneys. The results were similar in both types of polycythaemia.

The long term prognosis of adult patients with relapsed/refractory (R/R) acute lymphoblastic leu­kemia (ALL) is poor. There is no standard treatment for relapsed ALL and reinduction therapy should only be a “bridge treatment” in allogeneic hematopoietic stem cell transplantation (allo- -HSCT). In spite of obtaining an initial response to treatment, the duration of response using standard chemotherapy is usually short and the next relapses are chemoresistant. Immunotherapy with monoclonal antibodies as a targeted therapy represents a novel approach for treating patients with R/R ALL. The objective of immunotherapy is to improve the relapse-free and overall survival without increasing the toxicity of treatment. In this review, the mechanism of action and clini­cal efficacy of the novel bispecific antibody blinatumomab is discussed. The European Medicines Agency approved blinatumomab in 2015 for treating adult patients with Philadelphia chromosome negative R/R B-ALL.

Background Alpha-thalassemia is genetically transmitted hemolytic anemia resulting from disturbance of the globins chain synthesis. Alpha-thalassemia is caused most frequently by deletions and less commonly by nondeletional defects. Aim To introduce the molecular methods for routine identifications of alpha-thalassemia mutations and to study the characteristics of these mutations in Poland. Methods Blood sample of 155 patients with normal or reduced HbA2 values was obtained for blood counting. All samples underwent gap-PCR to screen for the seven common α-thal deletions and MLPA analysis. The DNA of 21 patients in which deletions were not detected has been directly sequenced. Results We detected mutations in the alpha-globin gene in 72 of 155 patients studied. 55 out of 72 cases showed most common thalassemia deletions, as the following: a single gene deletion (α3.7 and α4.2) and both genes deletion (FIL, SEA, MED I, and α20.5). Owing to the use of MLPA technique, we found nontypical deletions in another 12 patients and multiplication of the alpha-globin genes in further 4 cases. We also identified a patient with a point mutation HBA2: c.300 + 2T>A by DNA sequencing. Conclusions Molecular analysis of the alpha-globin cluster is required for a correct diagnosis in patients with normal or reduced level of HbA2. The results of the study show that due to the progressive migration of the population and globalization, thalassemia must be included in the differential diagnosis of anemia in Poland.

Monosomal karyotype (MK) and complex karyotype (CK) are poor prognostic factors in acute myeloid leukemia (AML). A comprehensive analysis of cytogenetic and clinical factors influencing an outcome of AML-CK+ was performed. The impact of cladribine containing induction on treatment results was also evaluated. We analyzed 125 patients with AML-CK+ treated within PALG protocols. MK was found in 75 (60%) individuals. The overall complete remission (CR) rate of 66 intensively treated patients was 62% vs. 28% in CK+ MK− and CK+ MK+ group (p = .01). No difference in CR rate was observed between DA and DAC arms. The overall survival (OS) in intensively treated patients was negatively influenced by MK, karyotype complexity (≥5 abnormalities), and WBC >20 G/L in multivariate analysis. The addition of cladribine to DA regimen improved OS only in MK− but not in MK+ group. In conclusion, concomitance of MK with ≥5 chromosomal abnormalities is associated with dismal treatment outcome in AMK-CK+.

Acquired copy number changes are common in acute leukemia. They are reported as recurrent amplifications or deletions (del), and may be indicative of involvement of oncogenes or tumor suppressor genes in acquired disease, as well as serving as potential biomarkers for prognosis or as targets for molecular therapy. The present study reported a gain of copy number of 14q13 to 14q32, leading to immunoglobulin heavy chain locus splitting in a young adult female. To the best of our knowledge, this rearrangement has not been previously reported in B-cell acute lymphoblastic leukemia (ALL). Low resolution banding cytogenetics performed at the time of diagnosis revealed a normal karyotype. However, retrospective application of fluorescence in situ hybridization (FISH) banding and locus-specific FISH probes, as well as multiplex ligation-dependent probe amplification and high resolution array-comparative genomic hybridization, revealed previously hidden aberrations. Overall, a karyotype of 46, XX, del(9) (p21.3 p21.3), derivative(14) (pter-> q32.33:: q32.33-> q13 ::q32.33-> qter) was determined. The patient was treated according to the Polish Adult Leukemia Group protocol and achieved complete remission. The results of the present study indicate that a favorable prognosis is associated with these aberrations when the aforementioned treatment is administered.

To the editor: Internal tandem duplication in the FLT3 gene ( FLT3- ITD) has been recognized as a marker conferring poor outcome in patients with normal karyotype acute myeloid leukemia (NK-AML).[1][1] Because of the inferior outcome of FLT3- ITD+ NK-AML patients when treated with standard

Acute myeloid leukemia (AML) cells harbor frequent mutations in genes responsible for epigenetic modifications. Increasing evidence of clinical role of DNMT3A and IDH1/2 mutations highlights the need for a robust and inexpensive test to identify these mutations in routine diagnostic work-up. Herein, we compared routinely used direct sequencing method with high-resolution melting (HRM) assay for screening DNMT3A and IDH1/2 mutations in patients with AML. We show very high concordance between HRM and Sanger sequencing (100% samples for IDH2-R140 and DNMT3-R882 mutations, 99% samples for IDH1-R132 and IDH2-R172 mutations). HRM method reported no false-negative results, suggesting that it can be used for mutations screening. Moreover, HRM displayed much higher sensitivity in comparison with DNA sequencing in all assessed loci. With Sanger sequencing, robust calls were observed when the sample contained 50% of mutant DNA in the background of wild-type DNA. In marked contrast, the detection limit of HRM improved down to 10% of mutated DNA. Given the ubiquitous presence of wild-type DNA background in bone marrow aspirates and clonal variations regarding mutant allele burden, these results favor HRM as a sensitive, specific, labor-, and cost-effective tool for screening and detection of mutations in IDH1/2 and DNMT3A genes in patients with AML.