The median OS was 2.4years (CI 05.5), 1.7years (CI: 04.4), 1.3years (CI 0.62.0), 1.5years (CI: 0.22.7), 0.9years (CI NC) and 2.3years (CI: 04.8), respectively. 10 1 10, K Dhner 2020 Impact of NPM1/FLT3-ITD genotypes defined by the 2017 European LeukemiaNet in patients with acute myeloid leukemia Blood 135 371 380, C Thiede 2002 Analysis of FLT3-activating mutations in 979 patients with acute myelogenous leukemia: Association with FAB subtypes and identification of subgroups with poor prognosis Blood 99 4326 4335, KM Murphy 2003 Detection of FLT3 Internal tandem duplication and D835 mutations by a multiplex polymerase chain reaction and capillary electrophoresis assay J. Mol. 2018 Oct 23;2 (20):2744-2754. doi: 10.1182/bloodadvances.2018020305. Correspondence to 109 3981 3992, DL Stirewalt 2006 Size of FLT3 internal tandem duplication has prognostic significance in patients with acute myeloid leukemia Blood 107 3724 3726, S Meshinchi 2008 Structural and numerical variation of FLT3/ITD in pediatric AML Blood 111 4930 4933, R Kusec 2006 More on prognostic significance of FLT3/ITD size in acute myeloid leukemia (AML) Blood 108 405 406, RE Gale 2008 The impact of FLT3 internal tandem duplication mutant level, number, size, and interaction with NPM1 mutations in a large cohort of young adult patients with acute myeloid leukemia Blood 111 2776 2784, Y Kim 2015 Quantitative fragment analysis of FLT3-ITD efficiently identifying poor prognostic group with high mutant allele burden or long ITD length Blood Cancer J. 1B) we add a second generation FLT3i to the intensive induction backbone of cladribine or fludarabine with cytarabine and idarubicin (CLIA or FIA, respectively) as published previously by our group61,62. Oncol. AR is defined as the ratio of ITD-mutated alleles to wild-type allele (FLT3ITD/FLT3 wild-type)13. Burnett, A. K., Russell, N. H. & Hills, R. K. Group obotUKNCRIAMLS. FLT3-ITD is located within exon 14, corresponding to JMD, in 70% of AML patients, while 30% of ITDs span exon 15, corresponding to the TKD1 domain. Internet Explorer). Google Scholar. Cortes, J. et al. Statistical analyses were performed with SPSS 19.0 (IBM, Armonk, NY). Leukemia 26, 23532359 (2012). Midostaurin has been approved and widely used in combination with induction and consolidation therapy in patients with newly diagnosed FLT3mut AML25. Regardless of prior FLT3i therapy, gilteritinib-treated patients had CRc rates >40%, however, the median OS with single-agent gilteritinib was 6.5 vs 9.6 months in prior FLT3i exposed (n=31) vs naive patients (n=216) with FLT3mut R/R AML74. In fact, every quartile increase in FLT3-ITD AR (from 0.01 to 0.20, 0.20 to 0.53, 0.53 to 0.80, 0.80 to 1.19) was associated with worsening complete remission (CR) rates, RFS, and OS, highlighting the prognostic value of AR. Google Scholar. Lymphoma 59 2273 2286, S Schnittger 2002 Analysis of FLT3 length mutations in 1003 patients with acute myeloid leukemia: Correlation to cytogenetics, FAB subtype, and prognosis in the AMLCG study and usefulness as a marker for the detection of minimal residual disease Blood 100 59 66, M Levis 2013 FLT3 mutations in acute myeloid leukemia: what is the best approach in 2013? However, in a recently released planned interim analysis, the study did not meet its primary endpoint of overall survival and may be terminated for futility46. Blood 110, 12621270 (2007). The primary resistance mechanisms include specific FLT3-TKD mutations (either single TKD mutations or compound mutations within the FLT3-ITD allele), mutations in genes other than FLT3, activation of alternative signaling pathways in leukemic cells or the bone marrow microenvironment that confer resistance to FLT3i68. 10-day decitabine with venetoclax for newly diagnosed intensive chemotherapy ineligible, and relapsed or refractory acute myeloid leukaemia: a single-centre, phase 2 trial. PubMed Central In patients 55 years, this regimen appeared to overcome the negative impact of FLT3-ITDmut in NPM1 co-mutated patients, regardless of the FLT3 AR, with comparable 3-year OS rates of 64% and 68% in FLT3-ITDmut NPM1mut and FLT3-ITDWT NPM1mut patients, respectively (P>0.05). The study protocol was conducted following the guidelines of the Declaration of Helsinki and approved by the Ethics Committee for Clinical Research of the Hospital UniversitarioFundacin Jimnez Daz (PIC169-18_FJD). No statistically significant differences were found (P=0.4) (Fig. Measurable residual disease, FLT3ITD mutation, and disease status have Alotaibi, A. S. et al. Additionally, different subdomains of TKD1 (HR or beta1-sheet) have been highlighted as those conferring an adverse outcome10. Correspondence to Lancet Oncol. Tallman, M. S. et al. J. Hematol. Biol. Precision Medicine in Myeloid Malignancies: Hype or Hope? We tried to validate the thresholds of ITD length previously published (i.e., 39bp and 70bp) in intensivelytreated AML patients (n=161). 93, 11361141 (2018). In order to improve the clinical condition of FLT3-ITD-positive patients, several FLT3 inhibitors have been developed showing variable results. J. Natl Cancer Inst. Acta Haematol. Upregulation of Bcl-2 confers resistance to FLT3 inhibition in FLT3-ITD AML with secondary acquired mutations. is a PhD candidate at Universidad Autnoma de Madrid (UAM). Article Cladribine added to daunorubicin-cytarabine induction prolongs survival of FLT3-ITD+ normal karyotype AML patients. We retrospectively reviewed 3555 acute myeloid leukemia patients, who have been assessed for FLT3 mutation at our institution . Prognostic implication of FLT3 and N-RAS gene mutations in acute myeloid leukemia. Phase I/II trial of the combination of midostaurin (PKC412) and 5-azacytidine for patients with acute myeloid leukemia and myelodysplastic syndrome. (C) OS according to the FLT3-ITD length and allelic ratio. and P.M.; Data curation, J.M.A. 5 96 102, C Sargas 2020 Networking for advanced molecular diagnosis in acute myeloid leukemia patients is possible: The PETHEMA NGS-AML project Haematologica https://doi.org/10.3324/haematol.2020.263806, Article Castao-Bonilla, T., Alonso-Dominguez, J.M., Barragn, E. et al. Studies have reported that a higher mutant allelic burden is associated with a worse prognosis. NGS, next-generation sequencing. Blood 129, 424447 (2017). Venetoclax combines synergistically with FLT3 inhibition to effectively target leukemic cells in FLT3-ITD+ acute myeloid leukemia models. Oran, B. et al. The AR was determined by fragment length analysis and calculated as previously described32. In patients with relapsed or refractory FLT3mut AML (Fig. Prevalence of FLT3, NPM1 and CEBPA Mutations and Correlation to Haematologica 106, 1034 (2020). Intensive fludarabine, high dose cytarabine and idarubicin-based induction for younger NPM1-mutated AML patient: overcoming the negative prognosis of FLT3-ITD mutation. J. Hematol. Google Scholar. We further compared the survival of patients with FLT3-ITD and those with FLT3-D835 mutation in the Positive/Positive and Negative/Positive groups (Figure 3). CNS Relapse in Acute Promyeloctyic Leukemia - academia.edu All samples investigated in this study were obtained at the time of diagnosis. Maiti et al. Molecular clearance of FLT3 was noted in 50% of all evaluable patients. Elderly patients with AML have a distinct genetic landscape compared with the younger population. QTc prolongation >500ms emerged as a significant adverse event36. Libura, M. et al. DiNardo, C. D. et al. In another randomized phase III study comparing post-ASCT sorafenib maintenance (n=100) to non-maintenance (n=102), sorafenib demonstrated an improved 1-year OS (82.1% vs 68%, P=0.012) and a decreased 1-year cumulative incidence of relapse (7% vs 24.5%, P=0.001) in FLT3-ITDmut AML patients undergoing ASCT in CR143. 31, 3681 (2013). Zhang, W. et al. Validation of ITD mutations in FLT3 as a therapeutic target in human acute myeloid leukaemia. The current European Leukemia Net (ELN) guidelines categorize FLT3 -ITDmut AML as favorable (NPM1mut with FLT3 wild-type Or NPM1mut with FLT3-ITD AR<0.5), intermediate (NPM1mut with FLT3-ITD AR>0.5 Or NPM1WT with FLT3-ITD AR<0.5), or adverse (NPM1WT with FLT3-ITD AR>0.5)18. Sorafenib maintenance in patients with FLT3-ITD acute myeloid leukaemia undergoing allogeneic haematopoietic stem-cell transplantation: an open-label, multicentre, randomised phase 3 trial. Approximately 30% of patients with newly diagnosed acute myeloid leukemia (AML) harbor mutations in the fms-like tyrosine kinase 3 (FLT3) gene. 383, 617629 (2020). Heart J. Suppl. J. Med. While both FLT3-ITD and FLT3-TKD mutations are common in AML with a normal karyotype, these mutations are also identified in AML with various karyotypic abnormalities. Our treatment approach for FLT3mut AML in MD Anderson Cancer Center is as follows: in newly diagnosed patients who are eligible to receive intensive chemotherapy (Fig. The FLT3-ITD AR was available in 140 intensively treated patients. Article The role of ASCT in patients with FLT3-ITDmut AR<0.50 with concomitant NPM1mut in the absence of concomitant high-risk features such as DNMT3A, TP53, or RUNX1 co-mutations, adverse cytogenetics, therapy-related or secondary AML, who achieve MRD negativity by high-sensitivity PCR (ideally for NPM1mut), or patients with FLT3-TKDmut is an area of ongoing debate. Cortes, J. E. et al. Only four out of 106 patients had ITD IS in the TKD1 domain. CR+CRi rates between groups were compared with a chi-square test. FMS-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD) is one of the most frequent mutations found in AML patients. J. Clinl. Background and aims: To explore the relationship between FLT3 (encoding Fms related tyrosine kinase 3) internal tandem duplication (ITD) mutations with the prognosis of acute promyelocytic leukemia. Mutations of FLT3 are found in approximately 30% of newly diagnosed AML patients and appear either as ITDs ( 25%) or point mutations in the tyrosine kinase domain (TKD) (710%)4. Password. On the other hand, we obtained a value (0.52) that was close to significant in the analysis of the prognostic impact of the FLT3-ITD AR according to the 2017 ELN cutoff8. Although common methylation . Canc. Additionally, the area under the ROC curve, which serves as an indicator of the diagnostic capacity of the ITD length as a whole, was 0.504. * Genes with a P value<0.05 in the MannWhitney test correlating mutational status with ITD length. Higher daunorubicin exposure benefits FLT3 mutated acute myeloid leukemia. Perl, A. E. et al. 15, 17 In our cohort, the prevalence of FLT3-ITD mutation of de novo AML patients was 21.5%. (B) Relapse-free survival. Recently, a double-blind placebo-controlled study reported a trend toward improved OS but not EFS with sorafenib combined with intensive chemotherapy in the frontline setting, especially among those with high FLT3-ITDmut AR >0.730. Scientific Reports (Sci Rep) Two randomized trials are evaluating the addition of gilteritinib vs midostaurin to induction and consolidation therapy in patients with newly diagnosed FLT3mut AML44 (NCT04027309, NCT03836209). The combination continues to enroll. Characteristics and outcome of patients with core binding factor acute myeloid leukemia and FLT3-ITD: results from an international collaborative study. Google Scholar. FLT3 -ITD mutations occur in the form of a replicated sequence in the juxtamembrane domain (JMD) and/or TKD1 of the FLT3 gene. Two cases with an NPM1 mut missense each occurred concomitant with type-A mutation. The sorafenib treatment arm had increased rates of adverse events, particularly diarrhea, bleeding, cardiac events, hand-foot-skin reaction, and rash but with no significant increase in the 30- or 60-day mortality between the two treatment arms. A Conventional approach. Despite the encouraging development of FLT3i, resistance to FLT3i is not uncommon and it can be either primary or secondary. Late relapse after hematopoietic stem cell transplantation for acute Authors Any variant allele frequency data were reported rarely. https://doi.org/10.1038/s41598-021-00050-x, DOI: https://doi.org/10.1038/s41598-021-00050-x. Quizartinib is also being evaluated in combination with CPX-351 (NCT04209725) and with CLIA (NCT04047641) in treatment naive and R/R FLT3mut AML. Xuan, L. et al. Blood 114, 29842992 (2009). SORMAIN, a placebo-controlled randomized phase II trial evaluated post-transplant sorafenib maintenance in patients with FLT3-ITDmut AML with RFS post-ASCT as the primary endpoint. To test the prognostic significance of the ITD length and its clinical applicability, we used recurrent previously published cutoffs, which were analyzed in series ranging from 28 to 100 intensively treated patients. PubMed Central Cancer Cell 1, 433443 (2002). It should be noted that MDS-MLD and -EB-1 patients with low and intermediate risk in IPSS-R were included in FLT3-ITD mutation group, and showed poor prognosis. J. Hematol. 2, 3 There are two types of FLT3 mutation, internal tandem duplication of FLT3 ( FLT3-ITD) and tyrosine kinase Front. AC220 is a uniquely potent and selective inhibitor of FLT3 for the treatment of acute myeloid leukemia (AML). Prognostic analyses were performed using the 70bp cutoff in 161 AML patients with FLT3-ITD mutations treated with IC (<70bp; n=119,70bp; n=42). This review describes key milestones in the clinical development of different FLT3-specific TKI with a . In the QuANTUM-R and ADMIRAL trials, only 4% and 12% of patients had received prior FLT3i therapy with induction, making it difficult to draw conclusions regarding the outcomes of contemporary patients, most of whom will have received a FLT3i (commonly midostaurin) with induction36,40. Studies of FLT3 mutations in paired presentation and relapse samples from patients with acute myeloid leukemia: implications for the role of FLT3 mutations in leukemogenesis, minimal residual disease detection, and possible therapy with FLT3 inhibitors. FLT3-ITD and its current role in acute myeloid leukaemia Fishers exact test was employed to correlate the ITD insertion site and mutational status. Interestingly, FLT3-ITD mutation, which has an adverse prognosis is found in up to one-third of younger patients but only 15-18% in >65 years. In general, quizartinib is well tolerated with minimal skin, gastrointestinal, or pulmonary side effects. Patterns of resistance differ in patients with acute myeloid leukemia treated with type I versus type II FLT3-inhibitors. Minetto, P. et al. Blood Cancer Discov. Moreover, ASCT in CR1 only benefitted patients with isolated FLT3-ITDmut (without NPM1mut) irrespective of AR (P<0.05)21. Commun. F fludarabine, I idarubicin, CL cladribine, A cytarabine 1.52g/m2, HMA hypomethylating agent, CR complete remission, ECOG PS Eastern Cooperative Oncology Group Performance Status, CG cytogenetics, MRD measurable residual disease, SCT stem cell transplant, HiDAC high-dose cytarabine, CBC complete blood count. The authors declare no competing interests. In a study that identified molecular mechanisms of resistance to gilteritinib, 32% of patients had emergent mutations in the RAS/MAPK pathway (K/NRAS), and 5% had emergent BCR/ABL1 fusions71. Venetoclax Added to Cladribine, Idarubicin, and Cytarabine with or without a FLT3 Inhibitor in Newly Diagnosed Acute Myeloid Leukemia (EHA, 2020). 135, 397402 (1986). FLT3-ITD mutations are detected in approximately 25% of newly diagnosed adult acute myeloid leukemia (AML) patients and confer an adverse prognosis. Intriguingly, this was the first large study to show that the FLT3i may also benefit FLT3 wild-type patients, perhaps through multi-kinase blockade or prevention of emergent FLT3 clones at relapse28. FLT3 -ITD and FLT3 point mutations show a gain-of-function phenotype with distinct signalling properties in vitro. Results of venetoclax and azacitidine combination in chemotherapy ineligible untreated patients with acute myeloid leukemia with FLT3 mutations. 95, 218223 (1996). We also analyzed the mutational profile of 118 FLT3-ITD AML patients with an NGS panel of 39 genes and correlated mutational status with the length and IS of ITD. We aimed to study the FLT3 gene mutation profile and prognosis in 139 adult Iranian patients with newly diagnosed AML. As we have already explained, our main goal was to validate two previous recurrently applied cutoffs: 39bp and 70bp. If material is not included in the articles Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. It's the most common genetic change in acute myeloid leukemia (AML), a type of leukemia that starts in the bone marrow and. Presented in part at the 42nd Annual Meeting of the American Society of Hematology, December 15, 2000, San Francisco, CA (abstract 2334). Changes in FLT3 mutation status can occur during the course of disease, but the clinical impact of a change is unclear. We stop the venetoclax and the FLT3i after Day 14 in patients who achieve marrow remission (<5% blasts) and/or marrow aplasia/hypoplasia/insufficiency (<5% cellularity). Not all FLT3-ITDmut are equal; the prognostic impact is influenced by the allele ratio (AR), insertion site, ITD length, co-mutations (NPM1), and karyotype. Nature 485, 260263 (2012). Overall survival (OS) was calculated from the date of the diagnosis of AML until death in all included patients. Mutations of SF3B1, EZH2 and WT1 seem to be a more ancestral event than FLT3 mutations, as expected, given the VAF of the genes. We currently recommend post-transplant maintenance with a FLT3i for at least 2 years (potentially indefinitely as there is limited data on the incidence of possible late relapses) in all FLT3mut AML. Regrettably, patients with information on the IS of ITD available had received different treatments: intensive chemotherapy, n=37; non-intensive therapy, n=14; clinical trials, n=6; and best supportive care, n=2. QuANTUM-R, a phase 3 randomized controlled trial, evaluated quizartinib monotherapy vs investigator choice salvage chemotherapy in R/R FLT3-ITDmut AML. 3). The FLT3-ITD allelic ratio has clear prognostic value. Its expression in acute myeloid leukemia (AML) is associated with a poor prognosis. Genomic and epigenomic landscapes of adult de novo acute myeloid leukemia. Sorafenib plus intensive chemotherapy improves survival in patients with newly diagnosed, FLT3-internal tandem duplication mutation-positive acute myeloid leukemia. The presence of FLT3-ITD mutation correlates with a high leukemic burden with increased risk of relapse and is recognized to be a driver mutation in patients with AML ( 5 ). Internal tandem duplication of the flt3 gene found in acute myeloid leukemia. Schneider F, Hoster E, Schneider S, Dufour A, Benthaus T, Kakadia PM, et al. Of note, we tested 3 different ITD length thresholds, and to be considered significant, the P value should be<0.025. volume11, Articlenumber:20745 (2021) 9, 10501063 (2019). Our results, alongside those of other non-significant reports, lead us to believe that FLT3-ITD length has neither prognostic value nor possible clinical application. Hematol. J. Med. However, the median OS was 19.2 months in FLT3-TKDmut AML (19.2 months), but only 11.5 months in FLT3-ITDmut patients65. The FLT3-ITD patient had trisomy 8. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. Information regarding the ITD insertion site and mutational status of another 38 genes recurrently mutated in myeloid neoplasms was available in 106 and 118 patients, respectively. Prognostic significance of FLT3-ITD length in AML patients treated with intensive regimens. Methods: We determined the status of ITD and TKD mutations using fragment analysis and the polymerase chain reaction-restriction fragment polymorphism method, respectively. CR or CRi was achieved in 70% of the patients in both groups (P=0.9). Selective inhibition of FLT3 by gilteritinib in relapsed or refractory acute myeloid leukaemia: a multicentre, first-in-human, open-label, phase 1-2 study.