Acute lymphoblastic leukemia (ALL) is a heterogeneous disease at the genetic level. Chromosomal abnormalities are used as diagnostic, prognostic and predictive biomarkers to provide subtype, outcome ...and drug response information. t(12;21)/ETV6-RUNX1 and high hyper-diploidy are good-risk prognostic biomarkers whereas KMT2A(MLL) translocations, t(17;19)/TCF3-HLF, haploidy or low hypodiploidy are high-risk biomarkers. t(9;22)/BCR-ABL1 patients require targeted treatment (imatinib/dasatinib), whereas iAMP21 patients achieve better outcomes when treated intensively. High-risk genetic biomarkers are four times more prevalent in adults compared to children. The application of genomic technologies to cases without an established abnormality (B-other) reveals copy number alterations which can be used either individually or in combination as prognostic biomarkers. Transcriptome sequencing studies have identified a network of fusion genes involving kinase genes -ABL1,ABL2,PDGFRB,CSF1R,CRLF2,JAK2 and EPOR in-vitro and in-vivo studies along with emerging clinical observations indicate that patients with a kinase-activating aberration may respond to treatment with small molecular inhibitors like imatinib/dasatinib and ruxolitinib. Further work is required to determine the true frequency of these abnormalities across the age spectrum and the optimal way to incorporate such inhibitors into protocols. In conclusion, genetic biomarkers are playing an increasingly important role in the management of patients with ALL.
Improved personalized adjustment of primary therapy to the perceived risk of relapse by using new prognostic markers for treatment stratification may be beneficial to patients with acute ...lymphoblastic leukemia (ALL). Here, we review the advances that have shed light on the role of IKZF1 aberration as prognostic factor in pediatric ALL and summarize emerging concepts in this field. Continued research on the interplay of disease biology with exposure and response to treatment will be key to further improve treatment strategies.
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Abstract Acute lymphoblastic leukaemia (ALL) occurs at all ages but is the most common cancer of childhood. The current treatment of paediatric ALL is highly successful with up to 90% children being ...cured. In contrast, survival rates for adult ALL are significantly lower at around 40%. The discovery and characterisation of genetic abnormalities have increased our understanding of the biology of the disease and provided important prognostic and predictive markers which have improved patient outcome. Not only is the spectrum of these aberrations vast but, due to advances in technology, continually expanding. A wide range of chromosomal and genomic abnormalities have been reported as being associated with patient outcome but only a subset are currently used to risk stratify patients. This review highlights the main genetic abnormalities which are used to manage patients with B-cell precursor ALL and discusses the evidence which has been accumulated on several newly described genomic abnormalities.
Diagnostic karyotype provides the framework for risk-stratification schemes in acute myeloid leukemia (AML); however, the prognostic significance of many rare recurring cytogenetic abnormalities ...remains uncertain. We studied the outcomes of 5876 patients (16-59 years of age) who were classified into 54 cytogenetic subgroups and treated in the Medical Research Council trials. In multivariable analysis, t(15;17)(q22;q21), t(8;21)(q22;q22), and inv(16)(p13q22)/t(16;16)(p13;q22) were the only abnormalities found to predict a relatively favorable prognosis (P < .001). In patients with t(15;17) treated with extended all-trans retinoic acid and anthracycline-based chemotherapy, additional cytogenetic changes did not have an impact on prognosis. Similarly, additional abnormalities did not have a significant adverse effect in t(8;21) AML; whereas in patients with inv(16), the presence of additional changes, particularly +22, predicted a better outcome (P = .004). In multivariable analyses, various abnormalities predicted a significantly poorer outcome, namely abn(3q) (excluding t(3;5)(q25;q34)), inv(3)(q21q26)/t(3;3)(q21;q26), add(5q)/del(5q), −5, −7, add(7q)/del(7q), t(6;11)(q27;q23), t(10;11)(p11∼13;q23), other t(11q23) (excluding t(9;11)(p21∼22;q23) and t(11;19)(q23;p13)), t(9;22)(q34;q11), −17, and abn(17p). Patients lacking the aforementioned favorable or adverse aberrations but with 4 or more unrelated abnormalities also exhibited a significantly poorer prognosis (designated “complex” karyotype group). These data allow more reliable prediction of outcome for patients with rarer abnormalities and may facilitate the development of consensus in reporting of karyotypic information in clinical trials involving younger adults with AML. This study is registered at http://www.isrctn.org as ISRCTN55678797 and ISRCTN17161961.
Purpose Minimal residual disease (MRD) and genetic abnormalities are important risk factors for outcome in acute lymphoblastic leukemia. Current risk algorithms dichotomize MRD data and do not ...assimilate genetics when assigning MRD risk, which reduces predictive accuracy. The aim of our study was to exploit the full power of MRD by examining it as a continuous variable and to integrate it with genetics. Patients and Methods We used a population-based cohort of 3,113 patients who were treated in UKALL2003, with a median follow-up of 7 years. MRD was evaluated by polymerase chain reaction analysis of Ig/TCR gene rearrangements, and patients were assigned to a genetic subtype on the basis of immunophenotype, cytogenetics, and fluorescence in situ hybridization. To examine response kinetics at the end of induction, we log-transformed the absolute MRD value and examined its distribution across subgroups. Results MRD was log normally distributed at the end of induction. MRD distributions of patients with distinct genetic subtypes were different ( P < .001). Patients with good-risk cytogenetics demonstrated the fastest disease clearance, whereas patients with high-risk genetics and T-cell acute lymphoblastic leukemia responded more slowly. The risk of relapse was correlated with MRD kinetics, and each log reduction in disease level reduced the risk by 20% (hazard ratio, 0.80; 95% CI, 0.77 to 0.83; P < .001). Although the risk of relapse was directly proportional to the MRD level within each genetic risk group, absolute relapse rate that was associated with a specific MRD value or category varied significantly by genetic subtype. Integration of genetic subtype-specific MRD values allowed more refined risk group stratification. Conclusion A single threshold for assigning patients to an MRD risk group does not reflect the response kinetics of the different genetic subtypes. Future risk algorithms should integrate genetics with MRD to accurately identify patients with the lowest and highest risk of relapse.
Summary Background Gemtuzumab ozogamicin was the first example of antibody-directed chemotherapy in cancer, and was developed for acute myeloid leukaemia. However, randomised trials in which it was ...combined with standard induction chemotherapy in adults have produced conflicting results. We did a meta-analysis of individual patient data to assess the efficacy of adding gemtuzumab ozogamicin to induction chemotherapy in adult patients with acute myeloid leukaemia. Methods We searched PubMed for reports of randomised controlled trials published in any language up to May 1, 2013, that included an assessment of gemtuzumab ozogamicin given to adults (aged 15 years and older) in conjunction with the first course of intensive induction chemotherapy for acute myeloid leukaemia (excluding acute promyelocytic leukaemia) compared with chemotherapy alone. Published data were supplemented with additional data obtained by contacting individual trialists. The primary endpoint of interest was overall survival. We used standard meta-analytic techniques, with an assumption-free (or fixed-effect) method. We also did exploratory stratified analyses to investigate whether any baseline features predicted a greater or lesser benefit from gemtuzumab ozogamicin. Findings We obtained data from five randomised controlled trials (3325 patients); all trials were centrally randomised and open label, with overall survival as the primary endpoint. The addition of gemtuzumab ozogamicin did not increase the proportion of patients achieving complete remission with or without complete peripheral count recovery (odds ratio OR 0·91, 95% CI 0·77–1·07; p=0·3). However, the addition of gemtuzumab ozogamicin significantly reduced the risk of relapse (OR 0·81, 0·73–0·90; p=0·0001), and improved overall survival at 5 years (OR 0·90, 0·82–0·98; p=0·01). At 6 years, the absolute survival benefit was especially apparent in patients with favourable cytogenetic characteristics (20·7%; OR 0·47, 0·31–0·73; p=0·0006), but was also seen in those with intermediate characteristics (5·7%; OR 0·84, 0·75–0·95; p=0·005). Patients with adverse cytogenetic characteristics did not benefit (2·2%; OR 0·99, 0·83–1·18; p=0·9). Doses of 3 mg/m2 were associated with fewer early deaths than doses of 6 mg/m2 , with equal efficacy. Interpretation Gemtuzumab ozogamicin can be safely added to conventional induction therapy and provides a significant survival benefit for patients without adverse cytogenetic characteristics. These data suggest that the use of gemtuzumab ozogamicin should be reassessed and its licence status might need to be reviewed. Funding None.
The Philadelphia chromosome positive arm of the UKALLXII/ECOG2993 study for adult acute lymphoblastic leukemia (ALL) enrolled 266 patients between 1993 and 2003 (pre-imatinib cohort). In 2003 ...imatinib was introduced as a single-agent course following induction (N = 86, late imatinib). In 2005 imatinib was added to the second phase of induction (N = 89, early imatinib). The complete remission (CR) rate was 92% in the imatinib cohort vs 82% in the preimatinib cohort (P = .004). At 4 years, the overall survival (OS) of all patients in the imatinib cohort was 38% vs 22% in the preimatinib cohort (P = .003). The magnitude of the difference between the preimatinib and imatinib cohorts in event-free survival (EFS), OS, and relapse-free survival (RFS) seen in univariate analysis was even greater in the multivariate analysis. In the preimatinib cohort, 31% of those starting treatment achieved hematopoietic stem cell transplant (alloHSCT) compared with 46% in the imatinib cohort. A Cox multivariate analysis taking alloHSCT into account showed a modest additional benefit to imatinib (hazard ratio for EFS = 0.64, 95% confidence interval 0.44-0.93, P = .02), but no significant benefit for OS and RFS. Adding imatinib to standard therapy improves CR rate and long-term OS for adults with ALL. A proportion of the OS benefit derives from the fact that imatinib facilitates alloHSCT. This trial was registered at clinicaltrials.gov as NCT00002514.
•Imatinib improves outcomes for adults with Ph+ ALL at least in part by facilitating allogeneic stem cell transplant.•Allogeneic hematopoietic stem cell transplant is not dispensible in Ph+ ALL in the imatinib era.
Summary Background No randomised study has shown whether stratification of treatment by minimal residual disease (MRD) response improves outcome in children and young people with acute lymphoblastic ...leukaemia (ALL). We assessed whether children and young people with clinical standard and intermediate-risk ALL who have persistent MRD at the end of induction therapy benefit from augmented post-remission therapy. Methods Between Oct 1, 2003, and June 30, 2011, we enrolled eligible patients aged 1–24 years and initially categorised them into clinical standard-risk, intermediate-risk, and high-risk groups on the basis of a combination of National Cancer Institute criteria, cytogenetics, and early morphological response to induction therapy. Clinical standard-risk and intermediate-risk patients with MRD of 0·01% or higher at day 29 of induction (MRD high risk) were randomly assigned (1:1) to standard therapy (treatment regimens A and B) or augmented post-remission therapy (regimen C). Compared with standard therapy, the augmented treatment regimen (regimen C) included an additional eight doses of pegylated asparaginase, 18 doses of vincristine, and escalated-dose intravenous methotrexate without folinic acid rescue during interim maintenance courses. Computer randomisation was used for treatment allocation and was balanced for sex, age (<10 years vs ≥10 years), and white blood cell count at diagnosis (<50 × 109 /L vs ≥50 × 109 /L) by minimisation. Patients, clinicians, and data analysts were not masked to treatment allocation. The primary outcomes were event-free survival and overall survival. Analyses were by intention to treat. This trial is registered with Current Controlled Trials, number ISRCTN07355119. Findings 533 MRD high-risk patients were randomly assigned to receive standard (n=266) or augmented (n=267) post-remission therapy. After a median follow-up of 70 months (IQR 52–91), 5-year event-free survival was better in the augmented treatment group (89·6% 95% CI 85·9–93·3) than in the standard group (82·8% 78·1–87·5; odds ratio OR 0·61 95% CI 0·39–0·98, p=0·04). Overall survival at 5 years was numerically, but not significantly, higher in the augmented treatment group (92·9% 95% CI 89·8–96·0) than in the standard therapy group (88·9% 85·0–92·8; OR 0·67 95% CI 0·38–1·17, p=0·16). More adverse events occurred in the augmented treatment group than in the standard group (asparaginase-related hypersensitivity in 18 6·7% in the augmented group vs two 0·8% in the standard group and asparaginase-related pancreatitis in eight 3·0% vs one 0·4%; intravenous methotrexate-related mucositis in 11 4·1% vs three 1·1% and methotrexate-related stomatitis in 48 18·0% vs 12 4·5%). Interpretation Our findings suggest that children and young people with acute lymphoblastic leukaemia and 0·01% or more MRD at the end of remission induction therapy could benefit from augmented post-remission therapy. However, the asparaginase and intravenous methotrexate used in the augmented treatment regimen is associated with more adverse events than is the standard post-remission treatment regimen. Funding Medical Research Council and Leukaemia and Lymphoma Research.
Recent genomic studies have provided a refined genetic map of acute lymphoblastic leukemia (ALL) and increased the number of potential prognostic markers. Therefore, we integrated copy-number ...alteration data from the 8 most commonly deleted genes, subordinately, with established chromosomal abnormalities to derive a 2-tier genetic classification. The classification was developed using 809 ALL97/99 patients and validated using 742 United Kingdom (UK)ALL2003 patients. Good-risk (GR) genetic features included ETV6-RUNX1, high hyperdiploidy, normal copy-number status for all 8 genes, isolated deletions affecting ETV6/PAX5/BTG1, and ETV6 deletions with a single additional deletion of BTG1/PAX5/CDKN2A/B. All other genetic features were classified as poor risk (PR). Three-quarters of UKALL2003 patients had a GR genetic profile and a significantly improved event-free survival (EFS) (94%) compared with patients with a PR genetic profile (79%). This difference was driven by a lower relapse rate (4% vs 17%), was seen across all patient subgroups, and was independent of other risk factors. Even genetic GR patients with minimal residual disease (>0.01%) at day 29 had an EFS in excess of 90%. In conclusion, the integration of genomic and cytogenetic data defines 2 subgroups with distinct responses to treatment and identifies a large subset of children suitable for treatment deintensification.
•Integrating cytogenetic and genomic data in pediatric ALL reveals 2 subgroups with different outcomes independent of other risk factors.•A total of 75% of children on UKALL2003 had a good-risk genetic profile, which predicted an EFS and OS of 94% and 97% at 5 years.
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