Wolfgang Kern

..The diagnosis and classification of myelodysplastic syndromes (MDS) is based on cytomorphology (CM) and cytogenetics (CG). Multiparameter flow cytometry (MFC) may add important diagnostic information...

..Clinical studies need to focus on a standardization of these approaches to facilitate the translation of MFC-based MRD assessment into therapeutic decisions in patients with AML...

..The objective of this review was to assess the impact of HDAraC during induction therapy for patients with AML based on results from randomized trials...

..ZAP-70 provides an important prognostic information in chronic lymphocytic leukemia (CLL); however, the most appropriate antibody clone and way of analysis have not yet been defined...

..Large clinical trials will determine the exact role and place of immunologic and RQ-PCR-based monitoring of MRD in the therapy of patients with AML...

..Thus, it is desirable to establish new molecular markers for PCR-based studies. Large clinical trials will determine the role and place of immunologic and PCR-based monitoring in the prognostic stratification of patients with AML...

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..INTERPRETATION AND CONCLUSIONS: FLT3 expression levels are correlated with clinical data, genetic subgroups as well as prognosis. Furthermore, our data indicate that FLT3 expression and signaling are closely associated with FAB M5...

..The proposed scoring systems for OS and TTT based on a combination of genetic markers improve the separation of prognostic subgroups in CLL already early in the course of the disease...

..The 1225 patients with de novo AML were separated according to age as follows: A1: 16 to 49 years (n=442), A2: 50 to 59 years (n=246), A3: 60-69 years (n=333), A4: 70 years and older (n=204)...

..Mean WBC count was highest in NPM1-mut/FLT3-ITD-positive and lowest in NPM1-wildtype/FLT3-ITD-negative patients (p<0.0001); similar for BM blasts. Therefore, FLT3-ITD and NPM1mut might synergistically stimulate blast proliferation...

..In the future, diagnostic procedures may include oligonucleotide microarray analysis (MA) to detect expression patterns of large numbers of specific genes...

..Similar results were obtained in patients undergoing second-line chemotherapy or allogeneic stem cell transplantation...

..MFC-based quantification of MRD reveals important prognostic information in unselected patients with AML in addition to cytogenetics and should be further evaluated and used in clinical trials...

..6%) and associated with a significant lower overall survival (P = 0.0339). In addition, cases with bcr3 showed a tendency for a worse event-free survival (P = 0.0795) compared with the bcr1 group...

..To refine cytogenetically based risk-stratification in acute myeloid leukemia (AML)...

..4%, 56.4%, 34.0%, 12.6%; mEFS: n.r., 18.1 months, 8.7 months, 2.5 months). The impact on outcome of this score was independent of NPM1mut/FLT3-ITD- status, MLL-PTD, and age...

..We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification...

..Therefore, some KD mutations (e.g., T315I) might be associated with higher genetic instability paving the way to additional cytogenetic and molecular genetic events...

..In conclusion, next-generation amplicon sequencing enables the highly sensitive detection of molecular mutations and is a feasible assay for routine assessment of GC-rich content amplicons...

..The present analysis aimed at improving the applicability of this approach to more patients with AML...

..We improved the identification of this parameter by implementing multiparameter flow cytometry to quantify bone marrow cells carrying leukemia-associated immunophenotypes (LAIP)...

..By combining the transcription ratios at these 2 checkpoints, a new powerful prognostic score has been established...

..Thus, MLD alone showed no independent clinical effect, whereas cytogenetics and MDS history were prognostically relevant...

..9%); and (5) very unfavorable: TP53 mutation (n = 80; OS at 3 years: 0%; P < .001). This comprehensive molecular characterization provides a more powerful model for prognostication than cytogenetics...

..Our study confirms the variety of ETV6 rearrangements in AML, MDS, and MPNs often in association with other genetic events. Prognosis of ETV6 rearranged de novo AML seems to be intermediate, which should be independently confirmed...

..However, there was a trend to better survival in most subgroups, especially when other molecular markers (FLT3-LM, MLL-PTD, and NPM) were taken into account...

..08 log (range, 1.22-4.01) and 2.28 log (range, 1.12-3.34) with and without CD45 gating. CD45 gating improves the sensitivity of MFC-based MRD monitoring in AML by 1 log...

..These data emphasize a close relationship between MBL and CLL regarding clinically relevant parameters and provide no evidence to strictly separate these entities by a distinct threshold of clonal B-cells...

..In conclusion, FLT3-mutations are extremely heterogenous with mutation load being the most relevant parameter...

..Finally, BCOR mutations tended to be associated with an inferior outcome in a cohort of 422 CN-AML patients (25.6% vs 56.7% overall survival at 2 years; P = .032). Our results for the first time implicate BCOR in CN-AML pathogenesis...

..Alterations of the short arm of chromosome 12 (12p) occur in various hematologic malignancies and ETV6 and CDKN1B, which are located on 12p, have been implicated as leukemogenic genes of interest...

..The detection of minimal residual disease (MRD) for predicting prognosis and for therapeutic planning still are under discussion...

..The results of the present study indicate that in the absence of FLT3 mutations, FLT3 overexpression might be a mechanism for FLT3 activation, which cooperates with RUNX1 mutations in leukemogenesis...

..In conclusion, t(8;21), +11, +13, and +14 are strongly associated with AML M0, M1, and M2. The FISH screening analyses identified abnormalities in an additional 3% in normal karyotypes...

..The introduction of all trans retinoic acid (ATRA) into treatment protocols has improved the outcome of APL dramatically. Therefore, it is essential to establish the diagnosis of APL as quickly and as reliably as possible...

..Multivariate analysis showed independent prognostic relevance for overall survival for RUNX1mut (P = .029), FLT3-ITD (P = .003), age (P < .001), and white blood cell count (P < .002)...

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..Thus far, data on a comprehensive cytogenetic or molecular genetic characterization are limited...

..These data support a possible future application of microarray technology for classification of the acute leukemias...

..80·1 months, P = 0·015). In conclusion, the del(14q) is a rare recurrent alteration in diverse mature B-cell neoplasms, shows variable size but distinct clustering of breakpoints, and is associated with short time to treatment...

..These data may be the basis for developing targeted therapeutic strategies to increase the cure rate in patients with AML and a complex aberrant karyotype...

..It is suggested to be expressed more weakly in patients with myelodysplastic syndromes (MDS). The analysis of MNDA therefore may improve diagnostic capabilities of multiparameter flow cytometry (MFC) in MDS...

..043). In conclusion, RUNX1 mutations are an important novel biomarker for a comprehensive characterization of T-cell acute lymphoblastic leukemia with poor prognostic impact and have implications for use also in monitoring disease...

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..Therefore, trisomy 8 in AML determines no specific disease characteristic but is a disease modulating secondary event...

..We demonstrate that FISH analysis underestimates the complexity of chromosomal aberrations in CLL. Therefore, conventional cytogenetics may define subgroups of patients with high risk of progression...

..Deleted sites on 13q14 appeared to be located within the breakpoint regions of the translocations. We show that mechanisms other than interstitial deletions may lead to loss of critical chromosomal regions in CLL...

..In conclusion, this study demonstrates that NPM1+/FLT3-LM- mutations are an independent predictor for a favorable outcome in AML with normal karyotype...

..In most patients with acute myeloid leukemia, multiparameter flow cytometry may be used to monitor minimal residual disease...

..0001), may partly contribute to the different phenotypes. However, linear regression analysis demonstrated that genes differentially expressed between M3 and M3v did not correlate with FLT3-LM...

..0001), LDH (P <.0001), and day 16 blasts (P =.0359). The prognostic significance of day 16 blasts is independent of pretherapeutic parameters and predicts outcome even in patients achieving a CR...

..Patients with KIT-D816-positive/AML1-ETO-positive AML might benefit from early intensification of treatment or combination of conventional chemotherapy with KIT PTK inhibitors...

..However, detailed data on the population-based age-dependent incidences of distinct cytogenetic subtypes as well as of molecular mutations are lacking...

..Gene expression profiling should also lead to the detection of new biological and clinically relevant subtypes in leukemia and therefore guide therapeutic decisions...

..001). In addition, 21 of 234 CML (9.0%) and 7 of 155 ALL (4.5%) cases carried the FLT3 D324N. Our data suggest that the FLT3 D324N variant might be associated with a predisposition to different subtypes of leukemia...

..Accordingly, cluster analysis completely separated all 13 subgroups analyzed. Gene expression profiling can predict all clinically relevant subentities of leukemia with high accuracy...

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..Furthermore, it is anticipated that new biologically defined and clinically relevant subtypes of leukemia will be identified based on gene expression profiling. This method may therefore guide therapeutic decisions...

..6 months; P =.0072) because of a higher relapse rate. Besides the importance of FLT3-LM for biologic and clinical characterization of AML, we show its value as a marker for disease monitoring based on 120 follow-up samples of 34 patients...

..In cases in which a myeloproliferative neoplasm cannot be established, analysis for TET2, CBL and EZH2 mutations may be indicated...

..001). In conclusion, we confirmed BRAFmut as a useful marker in HCL, its absence in HCL variant, and developed an RT-PCR-based assay to monitor minimal residual disease in HCL...

..039) especially in the age group < 60 years (P = .028). In conclusion, these data show that IDH1R132 may significantly add information regarding characterization and prognostication in AML...

..0 vs 8.9 months, P =.36). In conclusion, the category AML with 11q23/MLL abnormalities accounts for 2.8% of unselected AML, is closely associated with monocytic differentiation, and has a dismal prognosis. (..

..Furthermore, gene expression profiling may also lead to the detection of new biologically defined and clinically relevant subtypes in leukemia and guide therapeutic decision-making in the future...

..Thus, increasing WT1 levels in molecular responders may indicate Ph-negative clonal cytogenetic evolution during imatinib treatment...

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..In conclusion, the central role of morphology as defined by the FAB and WHO classification in AML at diagnosis is still justified in combination with other techniques...

..These data suggest that this patient developed a secondary therapy-related AML rather than a relapse...

..We therefore propose to focus staging systems of CML on the correlation of the percentage of bone marrow blasts and the cytogenetic results...

..A FIP1L1-PDGFRA fusion gene was identified in four male patients by interphase FISH and RT-PCR. These methods in combination demonstrated clonality in 8/40 patients (20%) with a male predominance (6/8; 75%)...

..Using conventional PCR it clearly could be shown that for most of the patients positive at presentation FLT3-LM is a reliable PCR marker for monitoring treatment response. Even an early detection of relapse was possible in some cases...

..By using two different strategies for microarray data analyses, this study revealed a unique correlation between AML-specific cytogenetic aberrations and gene expression profiles...

..Due to the rapid expansion of known molecular markers, this paper aims to outline some of the recent progress to improve understanding of the pathogenesis in these myeloid malignancies...

..Large clinical trials will determine the role of immunologic monitoring in the prognostic stratification of patients with AML...

..An ongoing international study (MILE study) is testing the accuracy, sensibility and specificity of gene expression profiling in leukemia diagnostics. First results and future directions will be given in the article...

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..The results serve as a mandatory prerequisite for individual treatment strategies and for the evaluation of treatment response using especially newly defined and highly specific MRD markers...

..262; p=0.012). Median age of onset was lower than in the V617Fmut controls (58.5 vs. 67.8 years, p<0.001). In conclusion, JAK2 exon 12 mutation analysis contributes to diagnostics in polycythemia vera or erythrocytosis...

..A stringent diagnostic algorithm for characterization, choice of treatment, and monitoring of MRD will be proposed in this review...

..Thus, diagnostics in the CMPD transform toward a multimodal diagnostic concept based on a combination of methods - cyto-/histomorphology, cytogenetics, and individual molecular methods which can be included in a diagnostic algorithm...

..As this is not a simple single nucleotide polymorphism, but a six-base pair insertion that leads to a two amino acid elongation of the protein, functional implications cannot be excluded...

..In ET and in HES the aberration rate was only 3 and 7%, respectively. Thus, cytogenetics can be omitted. However, in some of these cases molecular procedures should be integrated into the routine diagnostic process...

..Interlineage switch might result from an aberrant differentiation of the malignant clone or from selection within a mixed population...

..In conclusion, we demonstrated genetic, i.e. biological, differences between AML M5a and AML M5b and all other AML. Therefore, AML M5 should further be categorized as two different groups, as proposed by the WHO classification...

..Whether additional intensification can add to this effect has not yet been determined...

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..The incidence of submicroscopic deletions was 2-9% depending on the entity...

..The aim of this study was to clarify the relationship between AML and MDS by comparing the frequency of molecular mutations in the two conditions...

..Due to its close correlation with the course of the disease and with the risk of relapse the MRD represents an important prognostic parameter which is increasingly used for stratification of therapy in clinical trials...

..In contrast, we found an additional favorable impact of FLT3-TKD on EFS in prognostically favorable AML with NPM1- or CEBPA mutations...

..The following chapter gives an overview of the method of gene expression profiling of leukemia samples, its laboratory procedure, and how to approach the analysis of the data...