The study of minimal residual disease (MRD) in adult patients with acute lymphoblastic leukemia (ALL) allows a greater refinement of the individual risk classification and is the best support for ...risk-specific therapy with or without allogeneic hematopoietic cell transplantation (HCT). Using case-specific sensitive molecular probes or multiparametric flow cytometry on marrow samples obtained from the end of induction until midconsolidation, MRD assays can detect up to 1 leukemic cell of 10,000 total mononuclear cells (sensitivity, 0.01%; ie, ≥104). This cutoff, presently bound to technical limitations and subject to improvement, reflects the individual chemosensitivity and is strongly correlated with treatment outcome. The chance for cure is approximately 70% in the MRD-negative subset but only 20% to 30% in MRD-positive patients, in any diagnostic and risk subset. As shown by prospective trials from Germany, Italy, Spain, and France-Switzerland-Belgium, approximately 50% to 70% of unselected adult patients with Philadelphia-negative ALL achieve and maintain an early MRD response, whereas the remainder do not, including a substantial proportion of clinically standard-risk patients, and require an HCT to avert at least partially the risk of relapse. Along with the diffusion of more effective “pediatric-inspired” chemotherapy programs, the MRD analysis is an integral part of a modern management strategy, guiding the decision process to transplant or not, in which case nonrelapse mortality using HCT in first remission—still 10% to 20%—is totally abolished. The use of new agents such as monoclonal antibodies, small inhibitors, and chimeric antigen receptor T cells is opening a new era of MRD-directed therapies, that will further increase survival rates.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Activating mutations of KIT receptor tyrosine kinase have been reported in different neoplasms. The M541L KIT substitution (KIT(M541L)) has been described to be associated with pediatric ...mastocytosis, to enhance growth rate of the affected cells and to confer higher sensitivity to imatinib therapy. We investigated the presence of KIT(M541L) in five males with chronic eosinophilic leukemia, not otherwise specified (CEL, NOS), all negative for Platelet-derived growth factor-alpha (PDGFR) or PDGFRbeta abnormalities, which responded to imatinib therapy. To assess whether the mutation was constitutive or somatic in nature, we evaluated its presence analyzing either the neoplastic or normal cell population (epidermal cells or CD3-positive T lymphocytes). KIT(M541L) substitution was found in 4 out of 5 patients and in all it was somatic in nature. All patients were treated with low dose imatinib (100 mg daily orally), achieving complete and persistent clinical and hematological remission (median follow-up 74 months). One patient relapsed after 50 months. Our study strongly suggests to search for the KIT(M541L) in patients with CEL, NOS, negative for PDGFRalpha and PDGFRbeta abnormalities, to identify a subgroup of cases who may benefit from low dose imatinib therapy.
Introduction Patients with secondary acute myeloid leukemia (sAML) after myelodysplastic (MDS) or myeloproliferative neoplasms (MPN) treated with chemotherapy show poorer outcomes compared with de ...novo AML; consequently, these cases should be allocated to allogeneic stem cell transplant (alloSCT) whenever possible (Döhner H, Blood 2017). Some recent evidence suggested the potential of molecular characterization for implementing the current WHO definition (Arber DA, Blood 2016), since chromatin-splicing mutations have been reported to be highly specific for sAML (Lindsley RC, Blood 2015). However, this molecular signature has also been recognized in some clinically defined de novo AML cases (Papaemmanuil E, NEJM 2016). Based on this background, we assessed the clinical impact of chromatin-splicing mutational signature in clinically defined de novo AML patients enrolled into the prospective NILG 02/06 trial ClinicalTrials.gov Identifier: NCT00495287.
Patients and Methods The trial (Bassan R, Blood Advances 2019) randomized 574 newly diagnosed AML patients to receive induction (standard vs high-dose) followed by consolidative chemotherapy and/or alloSCT. For the present analysis, only patients with de novo AML (n=313) and WHO-defined sAML after MDS or MPN (n=101) with a full genetic characterization have been considered. Studies performed at diagnosis included conventional karyotype (n=412) and molecular analysis (n=414) and/or targeted NGS (this latter performed on 197 patients with normal karyotype). Patients with WHO-sAML were defined by the presence of an antecedent history of MDS or MPN (n=21) and/or cytogenetic WHO criteria of AML with MDS-related changes (n=80). Chromatin-splicing mutational signature defined the molecular-sAML group and comprised ASXL1, STAG2, BCOR, KMT2A-PTD, EZH2, PHF6, SRSF2, SF3B1, U2AF1, ZRS2 and RUNX1, excluding patients with WHO recurrent abnormalities.
Results Chromatin-splicing mutations were scored in 55/313 (17.6%) de novo AML patients (hereafter named molecular-sAML). The most frequently reported were KMT2A-PTD (45.5%), RUNX1 (44.4%) and ASXL1 (22.2%), while other mutations in the signature accounted for 5-17.5% of cases. Compared to de novo AML without chromatin-splicing mutations, patients with molecular-sAML and WHO-sAML were older (P<0.0001) and presented with lower white blood cell counts (WBC) (P<0.0001). The 3 groups were balanced in regards to induction regimen (P=0.5) and proportion of patients allocated to a consolidative alloSCT (31% in de novo AML, 30% in WHO-sAML and 33% in molecular-sAML, P=0.8). Complete remission (CR) after 1 or 2 induction cycles was achieved in 93% of de novo AML, 85% of molecular-sAML and 58% of WHO-sAML. In terms of 5-years overall survival (OS) and disease free survival (DFS), de novo AML patients did markedly better than both molecular and WHO-sAML patients (OS: 61%, P<0.0001; DFS: 54%, P<0.0009). Considering sAML patients, WHO-sAML had the worst OS when compared with molecular-sAML (18% vs 30%, P=0.02), but an overlapping DFS (22% vs 26%, P<0.3) (Figure 1). The negative impact of chromatin-splicing mutations was independently confirmed by multivariate analysis accounting for age, performance status, WBC and induction regimen HR 2.2 (CI 95% 1.48-3.25), P=0.0001. Among chromatin-splicing mutations, only RUNX1 and U2AF1 significantly affected OS HR 3.55 (CI 95% 1.28-9.87), P=0.01 and HR 6.87 (CI 95% 1.71-27.55), P=0.006. Finally, a consolidative alloSCT improved survival in all patients groups, most significantly in molecular and WHO-sAML (48% vs 24%, P=0.07 and 38% vs 8%, P=0.0001, respectively).
Conclusions Chromatin-splicing mutational signature identifies a distinct high-risk group within de novo AML patients, which shows clinical characteristics and outcomes closer to sAML than to de novo AML patients. These data highlight the need to detect this molecular signature at diagnosis and support a molecular definition of sAML.
Display omitted
Ferrero:Novartis: Honoraria. Corradini:Celgene: Honoraria, Other: Travel Costs; Gilead: Honoraria, Other: Travel Costs; Jazz Pharmaceutics: Honoraria; KiowaKirin: Honoraria; Kite: Honoraria; Novartis: Honoraria, Other: Travel Costs; Daiichi Sankyo: Honoraria; AbbVie: Consultancy, Honoraria, Other: Travel Costs; Amgen: Honoraria; Janssen: Honoraria, Other: Travel Costs; Roche: Honoraria; Sanofi: Honoraria; Servier: Honoraria; Takeda: Honoraria, Other: Travel Costs; BMS: Other: Travel Costs. Bassan:Incyte: Honoraria; Amgen Inc.: Honoraria; Pfizer: Honoraria; Shire: Honoraria. Rambaldi:Roche: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Research Funding, Speakers Bureau; Omeros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau, travel support.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Acute promyelocytic leukemia is a myeloid disorder that is characterized by the specific t(15;17) variant in ~98% of cases. The typical hypergranular and microgranular or hypogranular types exist, ...and are frequently associated with disseminated intravascular coagulopathy. Rare cases of promyelocytic leukemia-retinoic acid receptor α (PML-RARA) fusion without the reciprocal RARA-PML have been reported in cytogenetically normal samples. Conversely, fluorescence
hybridization (FISH) analysis has revealed a cryptic insertion of the RARA gene into the PML gene on chromosome 15. The current study reports a unique case with a normal karyotype and molecular evidence of the PML-RARA short isoform 3-fusion transcript, with FISH analysis revealing two fusion signals on the two copies of chromosome 15, but absence of the reciprocal on the two copies of chromosome 17. This finding raised the hypothesis of chromosome 15 uniparental isodysomy as consequence of normal chromosome 15 loss and duplication of the rearranged chromosome, as supported by polymorphic loci molecular analysis. The clinical, cytogenetic and molecular characterization of this case are presented and discussed in the present study.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•An improved pegaspargase-modified MRD and risk-oriented regimen was prospectively tested in adults aged 18-65 years with Ph– ALL/LL.•Three-year survival rates were >60% with HCT or chemotherapy, ...further improved by MRD negativity and age ≤40 years.
Display omitted
Pediatric-inspired chemotherapy is the standard of care for younger adults with Philadelphia chromosome–negative acute lymphoblastic leukemia/lymphoma (Ph– ALL/LL). In LAL1913 trial, the Gruppo Italiano Malattie EMatologiche dell’Adulto added pegaspargase 2000 IU/m2 to courses 1, 2, 5, and 6 of an 8-block protocol for patients aged from 18 to 65 years, with dose reductions in patients aged >55 years. Responders were risk stratified for allogeneic hematopoietic cell transplantation (HCT) or maintenance per clinical characteristics and minimal residual disease (MRD). Of 203 study patients (median age, 39.8 years), 91% achieved a complete remission. The 3-year overall survival, event-free, and disease-free survival (DFS) rates were 66.7%, 57.7%, and 63.3%, respectively, fulfilling the primary study end point of a 2-year DFS >55%. Although based on the intention-to-treat, the DFS being 74% and 50% in the chemotherapy (n = 94) and HCT (n = 91) assignment cohorts, respectively, a time-dependent analysis proved the value of HCT in patients who were eligible (DFS HCT 70% vs no HCT 26%; P <.0001). In multivariate analysis, age and MRD were independent factors predicting DFS rates of 86% (age ≤ 40 and MRD-negative), 64%-65% (MRD-positive or age > 40) and 25% (age > 40 and MRD-positive); P < .0001. Grade ≥2 pegaspargase toxicity was mainly observed at course 1, contributing to induction death in 2 patients but was rare thereafter. This program improved outcomes of patients with Ph– ALL/LL aged up to 65 years in a multicenter national setting. This trial was registered at www.clinicaltrials.gov as #NCT02067143.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Introduction: Myelofibrosis (MF) is the most aggressive form among Philadelphia negative (Ph-) myeloproliferative neoplasms (MPNs). In the last years, the mutational landscape of MF has expanded ...remarkably by the identification of additional recurrent mutations, called subclonal mutations.
Areas covered: Here we describe the available data about the currently identified subclonal mutations and their prognostic value in MF patients. We also review the practical value of including such molecular information in available prognostic models for both outcome prediction and possibly treatment decision with regards to transplant indication. Lastly, we covered the available data on the application of molecular markers for minimal residual disease (MRD) monitoring after transplantation.
Expert commentary: The demonstration of the prognostic value of additional mutations suggests to define this molecular profile at diagnosis and when an allogeneic transplant can be advised, particularly in younger patients. The presence of molecular markers might offer the possibility to evaluate the depth of remission and to monitor MRD after transplantation. Prospective clinical studies are needed to validate the use of this molecular data in the routine clinical practice.
Background and Aim of the Study
For both childhood and adult Acute Lymphoblastic Leukemia (ALL) patients, clinical risk factors such as age, white cell count, response to steroids, time to complete ...remission, as well as biologic characteristics such as immunophenotype and cytogenetic at diagnosis are important but not sufficient in predicting clinical outcome. Aberrations of TP53 play a crucial role in the molecular pathogenesis of leukemias and lymphomas in which their presence is associated to disease progression and represents a strong predictor of poor clinical outcome. In childhood ALL, hereditary and acquired TP53 mutations are involved both in the pathogenesis and progression of the disease. In adult ALL, TP53 mutations are frequent in patients negative for recurrent fusion genes and correlate with poor response to induction therapy (Chiaretti S. et al, Haematologica 2013). The aim of this study was to evaluate the impact of TP53 alterations, analyzed by Next Generation Sequencing (NGS), on the outcome of a cohort of T (n= 57) and B (n= 114) precursor, Philadelphia (Ph) negative, adult ALL patients enrolled into the NILG-ALL 09/2000 clinical trial (ClinicalTrials.gov identifier: NCT00358072, Bassan R. et al, Blood 2009) in which molecular minimal residual disease was used to guide post-remissional therapy.
Patients and Study design
Among the 171 patients who were investigated for TP53 mutations, 16 proved also positive for t(4;11) and 3 for t(1;19). We analyzed DNA isolated from mononuclear cells obtained from bone marrow or peripheral blood samples containing at least 30% of blasts at diagnosis. The TP53 gene was sequenced using 454 ultra-deep sequencing (Roche Diagnostics) for alterations in exons 4 to 11, following the protocol developed in the IRON-II consortium. The sequencing data were analyzed by the Roche Diagnostics GS Run Browser and GS Amplicon Variant Analyzer software. The probabilities of survival were estimated using the Kaplan Meier method. The log-rank test was used to compare survival probabilities between subgroups of patients.
Results and Discussion
The data obtained by NGS allowed to identify 15 coding mutations detected in the DNA binding domain region (exons 5 to 8). These alterations were observed at diagnosis in 14 patients (8%), (11 B-precursor ALL and 3 T-ALL). In 12 cases these aberrations were single nucleotide changes, in 2 cases we found a duplication (one of 4 and the other of 8 nucleotides) and in one case there was an 11 base pair DNA insertion. Remarkably, all of these DNA alterations led to missense or frame-shift mutations that introduced a premature stop codon. Moreover, they were detected with a wide range of allele burden (from 5% to 97%) pointing out that TP53 mutations can be present at diagnosis in different proportions within the leukemic clones. All patients carrying a TP53 alteration reached complete remission after induction therapy but 13 out of 14 suffered an early relapse. Frequency of relapses was significantly higher in mutated than in wild-type cases (p=0.019). Relapse DNA samples were available in 3 patients and in all of them we detected the same TP53 mutation found at diagnosis, indicating the presence of a stable mutated clone. The univariate analysis enlightens a clear relationship between TP53 mutation with an increasing age (p= 0.0003) but no correlation with other clinical features such as gender, hemoglobin, white blood count, platelets, percentage of blasts and cytogenetics at diagnosis. Moreover, patients with mutated TP53 showed a Disease Free Survival (DFS) and Overall Survival (OS) dramatically shorter than wild-type patients. The 2 years DFS was 43% in the TP53 non-mutated subjects compared to 7% in the mutated (p=0.0007). Similarly, the 2 years OS was of 50% in wild-type patients and of 7% in mutated patients (p=0.0011) (Figure 1).
Conclusions
In adult ALL, response to induction chemotherapy is not different in patients with a wild-type or a TP53 mutated gene, but in these latter cases the leukemia relapse rate is dramatically higher. The frequency of these mutations observed at diagnosis and the poor clinical outcome indicate the need of their identification during the diagnostic work up of adult ALL to guide treatment strategies. The use of a highly sensitive deep sequencing approach is crucial to identify also minor leukemic clones carrying TP53 mutations that may lead to the rapid emergence of a treatment resistant disease.
Display omitted
Kohlmann:AstraZeneca: Employment.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
