| 1. |
- Murari, A., et al.
(författare)
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A control oriented strategy of disruption prediction to avoid the configuration collapse of tokamak reactors
- 2024
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Ingår i: Nature Communications. - 2041-1723 .- 2041-1723. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- The objective of thermonuclear fusion consists of producing electricity from the coalescence of light nuclei in high temperature plasmas. The most promising route to fusion envisages the confinement of such plasmas with magnetic fields, whose most studied configuration is the tokamak. Disruptions are catastrophic collapses affecting all tokamak devices and one of the main potential showstoppers on the route to a commercial reactor. In this work we report how, deploying innovative analysis methods on thousands of JET experiments covering the isotopic compositions from hydrogen to full tritium and including the major D-T campaign, the nature of the various forms of collapse is investigated in all phases of the discharges. An original approach to proximity detection has been developed, which allows determining both the probability of and the time interval remaining before an incoming disruption, with adaptive, from scratch, real time compatible techniques. The results indicate that physics based prediction and control tools can be developed, to deploy realistic strategies of disruption avoidance and prevention, meeting the requirements of the next generation of devices.
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| 2. |
- Joffrin, E., et al.
(författare)
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Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
- 2019
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
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Forskningsöversikt (refereegranskat)abstract
- For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D-T campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the D-T preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling, and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, high confinement mode (H-mode) access, Be and W erosion, fuel recovery, etc). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and a mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating schemes (such as the three-ions scheme), new diagnostics (neutron camera and spectrometer, active Alfven eigenmode antennas, neutral gauges, radiation hard imaging systems...) and the calibration of the JET neutron diagnostics at 14 MeV for accurate fusion power measurement. The active preparation of JET for the 2020 D-T campaign provides an incomparable source of information and a basis for the future D-T operation of ITER, and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- Stroth, U., et al.
(författare)
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Progress from ASDEX Upgrade experiments in preparing the physics basis of ITER operation and DEMO scenario development
- 2022
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 62:4
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Tidskriftsartikel (refereegranskat)abstract
- An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L-H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced D α H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts.
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| 7. |
- Meyer, H.F., et al.
(författare)
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Overview of physics studies on ASDEX Upgrade
- 2019
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
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Forskningsöversikt (refereegranskat)abstract
- The ASDEX Upgrade (AUG) programme, jointly run with the EUROfusion MST1 task force, continues to significantly enhance the physics base of ITER and DEMO. Here, the full tungsten wall is a key asset for extrapolating to future devices. The high overall heating power, flexible heating mix and comprehensive diagnostic set allows studies ranging from mimicking the scrape-off-layer and divertor conditions of ITER and DEMO at high density to fully non-inductive operation (q 95 = 5.5, ) at low density. Higher installed electron cyclotron resonance heating power 6 MW, new diagnostics and improved analysis techniques have further enhanced the capabilities of AUG. Stable high-density H-modes with MW m-1 with fully detached strike-points have been demonstrated. The ballooning instability close to the separatrix has been identified as a potential cause leading to the H-mode density limit and is also found to play an important role for the access to small edge-localized modes (ELMs). Density limit disruptions have been successfully avoided using a path-oriented approach to disruption handling and progress has been made in understanding the dissipation and avoidance of runaway electron beams. ELM suppression with resonant magnetic perturbations is now routinely achieved reaching transiently . This gives new insight into the field penetration physics, in particular with respect to plasma flows. Modelling agrees well with plasma response measurements and a helically localised ballooning structure observed prior to the ELM is evidence for the changed edge stability due to the magnetic perturbations. The impact of 3D perturbations on heat load patterns and fast-ion losses have been further elaborated. Progress has also been made in understanding the ELM cycle itself. Here, new fast measurements of and E r allow for inter ELM transport analysis confirming that E r is dominated by the diamagnetic term even for fast timescales. New analysis techniques allow detailed comparison of the ELM crash and are in good agreement with nonlinear MHD modelling. The observation of accelerated ions during the ELM crash can be seen as evidence for the reconnection during the ELM. As type-I ELMs (even mitigated) are likely not a viable operational regime in DEMO studies of 'natural' no ELM regimes have been extended. Stable I-modes up to have been characterised using -feedback. Core physics has been advanced by more detailed characterisation of the turbulence with new measurements such as the eddy tilt angle - measured for the first time - or the cross-phase angle of and fluctuations. These new data put strong constraints on gyro-kinetic turbulence modelling. In addition, carefully executed studies in different main species (H, D and He) and with different heating mixes highlight the importance of the collisional energy exchange for interpreting energy confinement. A new regime with a hollow profile now gives access to regimes mimicking aspects of burning plasma conditions and lead to nonlinear interactions of energetic particle modes despite the sub-Alfvénic beam energy. This will help to validate the fast-ion codes for predicting ITER and DEMO.
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| 8. |
- Bilato, A., et al.
(författare)
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Impact of ICRF fast-ions on core turbulence and MHD activity in ASDEX upgrade
- 2023
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Ingår i: 24th Topical Conference On Radio-Frequency Power In Plasmas. - : AIP Publishing.
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Konferensbidrag (refereegranskat)abstract
- Experiments in various tokamaks and their analysis identify the fast ions (FI) generated by NBI and/or ICRF heating as one of the main causes of the observed improvement in core confinement: fast ions can reduce core microturbulence (mainly Ion-Temperature-Gradient (ITG) driven modes) either electrostatically or electromagnetically, or they can resonate with fishbones and high-frequency Alfvén modes, which in turn contribute in stabilizing ITG. In this perspective, we discuss recent experiments done on ASDEX Upgrade (AUG) where ICRF is the main actuator for FI generation for energies above 100 keV. Additionally, ICRF-FIs can substantially impact the MHD activity and its consequent effects on fast ion losses (FILs) and ion-cyclotron emission (ICE). We present dedicated AUG experiments with NBI-D further accelerated by ICRF.
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| 9. |
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| 10. |
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| 11. |
- Modvig, S, et al.
(författare)
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Value of flow cytometry for MRD-based relapse prediction in B-cell precursor ALL in a multicenter setting.
- 2021
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Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 1476-5551 .- 0887-6924. ; 35, s. 1894-1906
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Tidskriftsartikel (refereegranskat)abstract
- PCR of TCR/Ig gene rearrangements is considered the method of choice for minimal residual disease (MRD) quantification in BCP-ALL, but flow cytometry analysis of leukemia-associated immunophenotypes (FCM-MRD) is faster and biologically more informative. FCM-MRD performed in 18 laboratories across seven countries was used for risk stratification of 1487 patients with BCP-ALL enrolled in the NOPHO ALL2008 protocol. When no informative FCM-marker was available, risk stratification was based on real-time quantitative PCR. An informative FCM-marker was found in 96.2% and only two patients (0.14%) had non-informative FCM and non-informative PCR-markers. The overall 5-year event-free survival was 86.1% with a cumulative incidence of relapse (CIR5y) of 9.5%. FCM-MRD levels on days 15 (HzR 4.0, p<0.0001), 29 (HzR 2.7, p<0.0001), and 79 (HzR 3.5, p<0.0001) associated with hazard of relapse adjusted for age, cytogenetics, and WBC. The early (day 15) response associated with CIR5y adjusted for day 29 FCM-MRD, with higher levels in adults (median 2.4×10-2 versus 5.2×10-3, p<0.0001). Undetectable FCM- and/or PCR-MRD on day 29 identified patients with a very good outcome (CIR5y=3.2%). For patients who did not undergo transplantation, day 79 FCM-MRD>10-4 associated with a CIR5y=22.1%. In conclusion, FCM-MRD performed in a multicenter setting is a clinically useful method for MRD-based treatment stratification in BCP-ALL.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Modvig, S, et al.
(författare)
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Minimal residual disease quantification by flow cytometry provides reliable risk stratification in T-cell acute lymphoblastic leukemia
- 2019
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Ingår i: Leukemia. - : Nature Publishing Group. - 0887-6924 .- 1476-5551. ; 33:6, s. 1324-1336
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Tidskriftsartikel (refereegranskat)abstract
- Minimal residual disease (MRD) measured by PCR of clonal IgH/TCR rearrangements predicts relapse in T-cell acute lymphoblastic leukemia (T-ALL) and serves as risk stratification tool. Since 10% of patients have no suitable PCR-marker, we evaluated flowcytometry (FCM)-based MRD for risk stratification. We included 274 T-ALL patients treated in the NOPHO-ALL2008 protocol. MRD was measured by six-color FCM and real-time quantitative PCR. Day 29 PCR-MRD (cut-off 10-3) was used for risk stratification. At diagnosis, 93% had an FCM-marker for MRD monitoring, 84% a PCR-marker, and 99.3% (272/274) had a marker when combining the two. Adjusted for age and WBC, the hazard ratio for relapse was 3.55 (95% CI 1.4-9.0, p = 0.008) for day 29 FCM-MRD ≥ 10-3 and 5.6 (95% CI 2.0-16, p = 0.001) for PCR-MRD ≥ 10-3 compared with MRD < 10-3. Patients stratified to intermediate-risk therapy on day 29 with MRD 10-4-<10-3 had a 5-year event-free survival similar to intermediate-risk patients with MRD < 10-4 or undetectable, regardless of method for monitoring. Patients with day 15 FCM-MRD < 10-4 had a cumulative incidence of relapse of 2.3% (95% CI 0-6.8, n = 59). Thus, FCM-MRD allows early identification of patients eligible for reduced intensity therapy, but this needs further studies. In conclusion, FCM-MRD provides reliable risk prediction for T-ALL and can be used for stratification when no PCR-marker is available.
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| 16. |
- Modvig, S, et al.
(författare)
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Value of Flow Cytometry for MRD-Based Relapse Prediction in B-Cell Precursor Acute Lymphoblastic Leukemia in a Multi-Center Setting
- 2019
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Ingår i: Blood. - 0006-4971 .- 1528-0020.
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Konferensbidrag (refereegranskat)abstract
- Background: PCR of rearranged antigen receptor genes is the method of choice for MRD quantification in ALL. Although FCM-MRD is faster and biologically more informative than PCR, the analysis requires a high level of training. The only larger published studies using FCM-MRD based stratification (Borowitz, Blood, 2008 and 2015) showed a clear association with clinical outcome in BCP-ALL. However, MRD analyses were centralized and these studies included only one MRD-based stratification (MRD levels at the end of induction). Patients and methods: We examined FCM-MRD as stratification tool in BCP-ALL at various timepoints in a large-scale multicenter (18 MRD centers) study. A total of 1487 patients with BCP-ALL (1298 children (younger than 18 years) and 189 adults (18-45 years) are included in the study and were treated according to the NOPHO ALL2008 protocol between July 2008 and February 2016. The median follow-up time for patients in first remission was 51 months (IQR 32-75). MRD was measured by FCM and/or real time quantitative PCR on days 15, 29 (end of induction) and 79 (for standard (SR) and intermediate risk (IR) patients) and prior to and after high risk blocks. A 6-colour FCM analysis including 3 standardized antibody combinations was used and performed in 18 laboratories. Patients were stratified by FCM-MRD, or by PCR-MRD if no FCM-MRD marker was available. End-of-induction MRD (cut-off 10-3) was used to stratify patients to standard risk (SR) vs intermediate risk (IR) or IR vs high risk consolidation therapy (in case of WBC > 100 x 109/L at diagnosis). Patients with MRD >=2.5x10-1 on day 15 were stratified to high risk block therapy. Patients with MRD >=5x10-2 on day 29 or day 79/post high risk-2 block MRD >=10-3 were stratified to HSCT. Primary outcomes were 5year event-free survival (5y EFS) and 5year cumulative incidence of relapse (5y CIR). Results: Only two patients (0.14% of total) had neither an informative FCM nor a PCR marker, and an informative FCM marker combination for MRD monitoring was identified in 96.2% of patients. There was a significant correlation between FCM- and PCR-MRD levels on day 15 (r=0.77, p<0.0001, n=153) and 29 (r=0.81, p<0.0001, n=140). Based on FCM-MRD only, the median MRD level on day 15, 29 and 79/post high risk-2 block was 5x10-3, 1.1x10-4, and below detection limit, respectively. Adults had significantly higher MRD levels at all time-points (p<0.0001 for day 15 and 29, p=0.0019 for day 79, Mann-Whitney). The 5y EFS was 86.1% (95% CI 84.1-88.1) with a 5y CIR of 9.5% (95% CI 7.8-11.3, n=1487). The day 29 FCM-MRD level was closely associated with clinical outcome and a higher hazard of relapse was seen independently for a FCM-MRD >=10-3 (hazard ratio (HR) 2.4, CI 1.6-3.7, p<0.0001), age>18 year (HR 3.0, CI 1.7-5.3, p<0.0001), WBC>=100 (HR 2.7, CI 1.6-4.6, p=0.0001), and B-other (HR 2.1, CI 1.2-3.5, p=0.0052) or high risk B-ALL cytogenetic aberration (rearranged KMT2A/iAMPchr21/hypodiploid) (HR 3.2, CI 1.6-6.1, p=0.0006) (multivariate cause-specific Cox regression, n=1328). Patients with a day 79 FCM-MRD >=10-4 and <10-3 had a significantly higher CIR (22.1%, CI 10.8-33.5%, n=68) compared to FCM-MRD <10-4 (7.5%, CI 2.1-12.8%, n=110) or undetectable (6.3%, CI 4.5-8.2%, n=999, p=0.0087 for FCM-MRD >=10-4 and <10-3vs <10-4 or undetectable). After adjusting for WBC, age, and the day 29 FCM-MRD level, a day 79 FCM-MRD >=10-4 and <10-3 was still significantly associated with a worse 5y CIR for non-transplanted patients (HR 2.3, CI 1.19-4.36, p=0.012 compared to undetectable FCM-MRD, n=1171). Patients with day 15 FCM-MRD <10-3 had a significantly better 5y EFS (92.0%, CI 89.2-95.0%) and CIR (3.9%, CI 1.7-6.1%, n=432) than patients with FCM-MRD >=10-3 and <2.5x10-1, who had a 5y EFS of 85.5% (CI 82.7-88.3%, p=0.0016, n=837) and a 3-fold higher 5y CIR (11.0%, CI 8.4-13.5%, p<0.0001, n=432). Among patients with day 15 FCM-MRD<10-3, the relapse incidence was comparable for patients with FCM-MRD 10-4 - <10-3 and below 10-4 (CIR 3.6, CI 0.5-6.7 vs. CIR 4.1, CI 1.0-7.2, p=0.83, n=432). Conclusion: FCM-MRD performed in a multi-center setting is a clinically useful method for disease monitoring and MRD-based treatment stratification in BCP-ALL. Moreover, FCM-MRD is a reliable indicator of outcome in BCP-ALL independently of other key risk factors. Residual disease >=10-4 and <10-3 at day 79 in SR/IR patients not allocated to HSCT further identifies patients with a high risk of relapse.
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| 17. |
- Karlsson, Lene, et al.
(författare)
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Characteristics and outcome of primary resistant disease in paediatric acute myeloid leukaemia
- 2023
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Ingår i: British Journal of Haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 201:4, s. 757-765
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Tidskriftsartikel (refereegranskat)abstract
- A significant proportion of events in paediatric acute myeloid leukaemia (AML) are caused by resistant disease (RD). We investigated clinical and biological characteristics in 66 patients with RD from 1013 children with AML registered and treated according to the NOPHO-AML 93, NOPHO-AML 2004, DB AML-01 and NOPHO-DBH AML 2012 protocols. Risk factors for RD were age10 years or older and a white-blood-cell count (WBC) of 100 x 10(9)/L or more at diagnosis. The five-year overall survival (OS) was 38% (95% confidence interval [CI]: 28%-52%). Of the 63 children that received salvage therapy with chemotherapy, 59% (N = 37) achieved complete remission (CR) with OS 57% (95% CI: 42%-75%) compared to 12% (95% CI: 4%-35%) for children that did not achieve CR. Giving more than two salvage chemotherapy courses did not increase CR rates. OS for all 43 patients receiving allogeneic haematopoietic stem cell transplantation (HSCT) was 49% (95% CI: 36%-66%). Those achieving CR and proceeding to HSCT had an OS of 56% (95% CI: 41%-77%, N = 30). This study showed that almost 40% of children with primary resistant AML can be cured with salvage therapy followed by HSCT. Children that did not achieve CR after two salvage courses with chemotherapy did not benefit from additional chemotherapy.
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| 18. |
- Karlsson, Lene, et al.
(författare)
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Fusion transcript analysis reveals slower response kinetics than multiparameter flow cytometry in childhood acute myeloid leukaemia
- 2022
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Ingår i: International Journal of Laboratory Hematology. - : Wiley. - 1751-5521 .- 1751-553X. ; 44:6, s. 1094-1101
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Analysis of measurable residual disease (MRD) is increasingly being implemented in the clinical care of children and adults with acute myeloid leukaemia (AML). However, MRD methodologies differ and discordances in results lead to difficulties in interpretation and clinical decision-making. The aim of this study was to compare results from reverse transcription quantitative polymerase chain reaction (RT-qPCR) and multiparameter flow cytometry (MFC) in childhood AML and describe the kinetics of residual leukaemic burden during induction treatment. Methods In 15 children who were treated in the NOPHO-AML 2004 trial and had fusion transcripts quantified by RT-qPCR, we compared MFC with RT-qPCR for analysis of MRD during (day 15) and after induction therapy. Eight children had RUNX1::RUNX1T1, one CBFB::MYH11 and six KMT2A::MLLT3. Results When >= 0.1% was used as cut-off for positivity, 10 of 22 samples were discordant. The majority (9/10) were MRD positive with RT-qPCR but MRD negative with MFC, and several such cases showed the presence of mature myeloid cells. Fusion transcript expression was verified in mature cells as well as in CD34 expressing cells sorted from diagnostic samples. Conclusions Measurement with RT-qPCR suggests slower response kinetics than indicated from MFC, presumably due to the presence of mature cells expressing fusion transcript. The prognostic impact of early measurements with RT-qPCR remains to be determined.
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| 19. |
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| 20. |
- van Weelderen, Romy E., et al.
(författare)
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Measurable residual disease and fusion partner independently predict survival and relapse risk in childhood KMT2A-rearranged acute myeloid leukemia : a study by the international Berlin-Frankfurt-Münster study group
- 2023
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Ingår i: Journal of Clinical Oncology. - : American Society of Clinical Oncology (ASCO). - 0732-183X .- 1527-7755. ; 41:16, s. 2963-2974
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: A previous study by the International Berlin-Frankfurt-Münster Study Group (I-BFM-SG) on childhood KMT2A-rearranged (KMT2A-r) AML demonstrated the prognostic value of the fusion partner. This I-BFM-SG study investigated the value of flow cytometry-based measurable residual disease (flow-MRD) and evaluated the benefit of allogeneic stem-cell transplantation (allo-SCT) in first complete remission (CR1) in this disease.Methods: A total of 1,130 children with KMT2A-r AML, diagnosed between January 2005 and December 2016, were assigned to high-risk (n = 402; 35.6%) or non-high-risk (n = 728; 64.4%) fusion partner-based groups. Flow-MRD levels at both end of induction 1 (EOI1) and 2 (EOI2) were available for 456 patients and were considered negative (<0.1%) or positive (≥0.1%). End points were 5-year event-free survival (EFS), cumulative incidence of relapse (CIR), and overall survival (OS).Results: The high-risk group had inferior EFS (30.3% high risk v 54.0% non-high risk; P < .0001), CIR (59.7% v 35.2%; P < .0001), and OS (49.2% v 70.5%; P < .0001). EOI2 MRD negativity was associated with superior EFS (n = 413; 47.6% MRD negativity v n = 43; 16.3% MRD positivity; P < .0001) and OS (n = 413; 66.0% v n = 43; 27.9%; P < .0001), and showed a trend toward lower CIR (n = 392; 46.1% v n = 26; 65.4%; P = .016). Similar results were obtained for patients with EOI2 MRD negativity within both risk groups, except that within the non-high-risk group, CIR was comparable with that of patients with EOI2 MRD positivity. Allo-SCT in CR1 only reduced CIR (hazard ratio, 0.5 [95% CI, 0.4 to 0.8]; P = .00096) within the high-risk group but did not improve OS. In multivariable analyses, EOI2 MRD positivity and high-risk group were independently associated with inferior EFS, CIR, and OS.Conclusion: EOI2 flow-MRD is an independent prognostic factor and should be included as risk stratification factor in childhood KMT2A-r AML. Treatment approaches other than allo-SCT in CR1 are needed to improve prognosis.
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| 21. |
- van Weelderen, Romy E., et al.
(författare)
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Optimized cytogenetic risk-group stratification of KMT2A-rearranged pediatric acute myeloid leukemia
- 2024
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Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 8:12, s. 3200-3213
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Tidskriftsartikel (refereegranskat)abstract
- A comprehensive international consensus on the cytogenetic risk-group stratification of KMT2A-rearranged (KMT2A-r) pediatric acute myeloid leukemia (AML) is lacking. This retrospective (2005-2016) International Berlin-Frankfurt-Münster Study Group study on 1256 children with KMT2A-r AML aims to validate the prognostic value of established recurring KMT2A fusions and additional cytogenetic aberrations (ACAs) and to define additional, recurring KMT2A fusions and ACAs, evaluating their prognostic relevance. Compared with our previous study, 3 additional, recurring KMT2A-r groups were defined: Xq24/KMT2A::SEPT6, 1p32/KMT2A::EPS15, and 17q12/t(11;17)(q23;q12). Across 13 KMT2A-r groups, 5-year event-free survival probabilities varied significantly (21.8%-76.2%; P < .01). ACAs occurred in 46.8% of 1200 patients with complete karyotypes, correlating with inferior overall survival (56.8% vs 67.9%; P < .01). Multivariable analyses confirmed independent associations of 4q21/KMT2A::AFF1, 6q27/KMT2A::AFDN, 10p12/KMT2A::MLLT10, 10p11.2/KMT2A::ABI1, and 19p13.3/KMT2A::MLLT1 with adverse outcomes, but not those of 1q21/KMT2A::MLLT11 and trisomy 19 with favorable and adverse outcomes, respectively. Newly identified ACAs with independent adverse prognoses were monosomy 10, trisomies 1, 6, 16, and X, add(12p), and del(9q). Among patients with 9p22/KMT2A::MLLT3, the independent association of French-American-British-type M5 with favorable outcomes was confirmed, and those of trisomy 6 and measurable residual disease at end of induction with adverse outcomes were identified. We provide evidence to incorporate 5 adverse-risk KMT2A fusions into the cytogenetic risk-group stratification of KMT2A-r pediatric AML, to revise the favorable-risk classification of 1q21/KMT2A::MLLT11 to intermediate risk, and to refine the risk-stratification of 9p22/KMT2A::MLLT3 AML. Future studies should validate the associations between the newly identified ACAs and outcomes and unravel the underlying biological pathogenesis of KMT2A fusions and ACAs.
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