Early response to induction is predictive of survival in childhood Philadelphia chromosome positive acute lymphoblastic leukaemia: results of the Medical Research Council ALL 97 trial

Demographics and Outcome of Philadelphia-positive ALL in a Pediatric Population in North India: a Single-center Experience

Philadelphia-positive (Ph+) acute lymphoblastic leukemia (ALL) in children had a worse outcome before the use of tyrosine kinase inhibitors. We have evaluated the demographics and outcome of Ph+ ALL patients treated with imatinib without blood marrow transplantation. Of the 206 children with ALL registered for treatment, the demographic data of 15 Ph+ ALL patients were compared with the remaining Ph- patients. Imatinib (340 mg/m) was started on day 5 (D5) of induction in Ph+ patients, and their overall survival was compared with Ph- high-risk patients treated on similar protocols. Statistical analysis was carried out by the Fisher exact test and the t test. The Kaplan-Meier test was used for survival analysis. Philadelphia positivity noted in 15/206 (7.28%) ALL patients was higher than reported earlier. Median initial total leukocyte count and central nervous system positivity were significantly higher in Ph+ patients. Myeloid markers, CD13 and CD33, were also positive in 33.3% Ph+ patients. D15 and D35 marrow showed remissions in a larger proportion of Ph+ ALL, as compared with Ph- patients, but chemotherapy interruptions and neutropenic deaths were significantly higher after starting imatinib, as compared with Philadelphia high-risk patients. Overall survival was similar in Ph+ and Ph- high-risk ALL patients. Ph+ ALL, noted in 7.28%, presented with high initial white blood cell counts, high central nervous system positivity, poor steroid response, and higher induction deaths, as compared with high-risk Ph- ALL, and raised the question about the appropriate dose and time of introduction of imatinib to prevent toxicity.

Outcome and prognostic factors of children with Philadelphia chromosome-positive acute lymphoblastic leukemia treated with imatinib followed by allogeneic hematopoietic cell transplantation in first remission

Background

Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) is a subset of ALL with poor prognosis. Here, we analyzed the outcomes and prognostic factors of children with Ph+ ALL who received imatinib and chemotherapy followed by allogeneic hematopoietic cell transplantation (HCT) in first complete remission (CR).

Methods

Thirty-one Ph+ ALL patients (female 10) diagnosed from January 2005 to December 2016 were included in the study. All patients were treated with imatinib and chemotherapy before HCT. Bone marrow (BM) evaluations included real-time quantitative polymerase chain reaction (RQ-PCR) study of the BCR-ABL1 fusion transcript. All patients received HCT with total body irradiation (TBI)-based conditioning at a median of 6.4 (range, 4.2-47.1) months from diagnosis.

Results

Compared to values at diagnosis, the median decrement of RQ-PCR value post-consolidation, and prior to HCT was -3.7 Log and -4.8 Log, respectively. The 5-year event-free survival (EFS) and overall survival of the patients were 64.5±9.4% (20/31) and 75.0±8.3% (23/31) respectively. Events included relapse (N=5) and death in CR post-HCT (N=6). The 5-year incidence of molecular relapse was 30.9±9.1% (9/31). An RQ-PCR decrement of at least -4 Log post-consolidation significantly predicted lower incidence of molecular relapse: 7.7±7.7% for ≥-4 Log decrement, 50.0±13.8% for <-4 Log decrement (P=0.027).

Conclusion

Decrement in RQ-PCR for the BCR-ABL1 transcript that was determined after consolidation was the only significant prognostic factor for incidence of molecular relapse. In the post-induction TKI initiation setting, steadfast imatinib treatment during consolidation may allow for optimum post-HCT outcomes.

Favorable outcome of allogeneic hematopoietic stem cell transplantation followed by post-transplant treatment with imatinib in children with Philadelphia chromosome-positive acute lymphoblastic leukemia

Background

Allogeneic hematopoietic stem cell transplantation (HSCT) is the preferred curative therapy for children with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). We evaluated the treatment outcomes of children with Ph+ ALL who underwent allogeneic HSCT.

Methods

Fifteen children diagnosed with Ph+ ALL in Asan Medical Center Children's Hospital between 1998 and 2012 were retrospectively analyzed.

Results

Of 521 children diagnosed with ALL during the study period, 15 had a Philadelphia chromosome. Among these 15 patients, 13 attained complete remission (CR) following induction chemotherapy, and two died of intracerebral hemorrhage during leukapheresis and induction chemotherapy, respectively. Of the 13 patients who attained CR, 12 received allogeneic HSCT, mainly from unrelated donors. Of the 12 patients who received HSCT, one died of a transplant-related cause, one died of relapse after HSCT, and 10 remain in continuous CR. Of the 10 patients who remained in CR longer than six months after HSCT, seven received post-HSCT imatinib. For all 15 patients, the 5-year overall survival, event-free survival, and cumulative incidence of relapse were 60.0%, 48.6%, and 38.8%, respectively, with a median follow-up of 70 months. For the HSCT group, the 5-year overall survival, event-free survival, and cumulative incidence of relapse were 80.2%, 72.9%, and 29.3%, respectively, with a median follow-up of 100 months.

Conclusion

Allogeneic HSCT cures a significant proportion of Ph+ ALL patients. Because the use of imatinib appears to be a promising approach, strategies that include tyrosine kinase inhibitors before and after HSCT require further evaluation.

Treatment including anthracyclines versus treatment not including anthracyclines for childhood cancer

BACKGROUND

One of the most important adverse effects of anthracyclines is cardiotoxicity. A well-informed decision on the use of anthracyclines in the treatment of childhood cancers should be based on evidence regarding both antitumour efficacy and cardiotoxicity. This review is the second update of a previously published Cochrane review.

OBJECTIVES

To compare antitumour efficacy (survival and tumour response) and cardiotoxicity of treatment including or not including anthracyclines in children with childhood cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 6), MEDLINE (1966 to July 2013) and EMBASE (1980 to July 2013). In addition, we searched reference lists of relevant articles and conference proceedings, the International Society for Paediatric Oncology (SIOP) (from 2002 to 2012) and American Society of Clinical Oncology (ASCO) (from 2002 to 2013). We have searched for ongoing trials in the ISRCTN register and the National Institute of Health register (both screened August 2013) (http://www.controlled-trials.com).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing treatment of any type of childhood cancer with and without anthracyclines and reporting outcomes concerning antitumour efficacy or cardiotoxicity.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the study selection, risk of bias assessment and data extraction. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We identified RCTs for seven types of tumour, acute lymphoblastic leukaemia (ALL) (three trials; 912 children), Wilms' tumour (one trial; 316 children), rhabdomyosarcoma and undifferentiated sarcoma (one trial; 413 children), Ewing's sarcoma (one trial; 94 children), non-Hodgkin lymphoma (one trial; 284 children), hepatoblastoma (one trial; 255 children) and acute myeloid leukaemia (AML) (one trial; 394 children). All studies had methodological limitations. For ALL no evidence of a significant difference in antitumour efficacy was identified in the meta-analyses, but in most individual studies there was a suggestion of better antitumour efficacy in patients treated with anthracyclines. For both Wilms' tumour and Ewing's sarcoma a significant difference in event-free and overall survival in favour of treatment with anthracyclines was identified, although for Wilms' tumour the significant difference in overall survival disappeared with long-term follow-up. For rhabdomyosarcoma and undifferentiated sarcoma, non-Hodgkin lymphoma and hepatoblastoma no difference in antitumour efficacy between the treatment groups was identified. The same was true for AML, with the exception of overall survival in a post hoc analysis in a subgroup of patients with relapsed core binding factor (CBF)-AML in which patients treated with anthracyclines did better. Clinical cardiotoxicity was evaluated in four RCTs; no significant difference between the treatment groups was identified, but in all individual studies there was a suggestion of a lower rate of clinical cardiotoxicity in patients who did not receive anthracyclines. None of the studies evaluated asymptomatic cardiac dysfunction. No RCTs were identified for other childhood cancers.

AUTHORS' CONCLUSIONS

At the moment no evidence from RCTs is available which underscores the use of anthracyclines in ALL. However, 'no evidence of effect', as identified in this review, is not the same as 'evidence of no effect'. For Wilms' tumour, rhabdomyosarcoma and undifferentiated sarcoma, Ewing's sarcoma, non-Hodgkin lymphoma, hepatoblastoma and AML only one RCT was available for each type and, therefore, no definitive conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours. For other childhood cancers no RCTs were identified and therefore no conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours.

Current and future management of Ph/BCR-ABL positive ALL

Following the introduction of targeted therapy with tyrosine kinase inhibitors (TKI) at the beginning of the past decade, the outcome of patients with Philadelphia-chromosome positive acute lymphoblastic leukemia (Ph+ ALL) has dramatically improved. Presently, the use of refined programs with first/second generation TKI's and chemotherapy together with allogeneic stem cell transplantation allow up to 50% of all patients to be cured. Further progress is expected with the new TKI ponatinib, overcoming resistance caused by T315I point mutation, other targeted therapies, autologous transplantation in molecularly negative patients, therapeutic monoclonal antibodies like inotuzumab ozogamicin and blinatumomab, and chimeric antigen receptor-modified T cells. Ph+ ALL could become curable in the near future even without allogeneic stem cell transplantation, minimizing the risk of therapy-related death and improving greatly the quality of patients' life.

BET inhibition as a single or combined therapeutic approach in primary paediatric B-precursor acute lymphoblastic leukaemia

Paediatric B-precursor ALL is a highly curable disease, however, treatment resistance in some patients and the long-term toxic effects of current therapies pose the need for more targeted therapeutic approaches. We addressed the cytotoxic effect of JQ1, a highly selective inhibitor against the transcriptional regulators, bromodomain and extra-terminal (BET) family of proteins, in paediatric ALL. We showed a potent in vitro cytotoxic response of a panel of primary ALL to JQ1, independent of their prognostic features but dependent on high MYC expression and coupled with transcriptional downregulation of multiple pro-survival pathways. In agreement with earlier studies, JQ1 induced cell cycle arrest. Here we show that BET inhibition also reduced c-Myc protein stability and suppressed progression of DNA replication forks in ALL cells. Consistent with c-Myc depletion and downregulation of pro-survival pathways JQ1 sensitised primary ALL samples to the classic ALL therapeutic agent dexamethasone. Finally, we demonstrated that JQ1 reduces ALL growth in ALL xenograft models, both as a single agent and in combination with dexamethasone. We conclude that targeting BET proteins should be considered as a new therapeutic strategy for the treatment of paediatric ALL and particularly those cases that exhibit suboptimal responses to standard treatment.

Where do we stand in the treatment of relapsed acute lymphoblastic leukemia?

Acute lymphoblastic leukemia (ALL) is the most common and one of the most treatable cancers in children. Although the majority of children with ALL are now cured, 10%-20% of patients are predicted to relapse and outcomes with salvage therapy have been disappointing, with approximately only one-third of children surviving long-term after disease recurrence. Several prognostic factors have been identified, with timing of recurrence relative to diagnosis and site of relapse emerging as the most important variables. Despite heterogeneity in the elements of salvage therapy that are delivered in trials conducted internationally, outcomes have been remarkably similar and have remained static. Because most intensive salvage regimens have reached the limit of tolerability, current strategies are focusing on identifying new agents tailored to the unique biology of relapsed disease and identifying methods to develop these agents efficiently for clinical use. Recently, high-resolution genomic analyses of matched pairs of diagnostic and relapse bone marrow samples are emerging as a promising tool for identifying pathways that impart chemoresistance.

Individualized leukemia cell-population profiles in common B-cell acute lymphoblastic leukemia patients

Immunophenotype is critical for diagnosing common B-cell acute lymphoblastic leukemia (common ALL) and detecting minimal residual disease. We developed a protocol to explore the immunophenotypic profiles of common ALL based on the expression levels of the antigens associated with B lymphoid development, including IL-7Rα (CD127), cytoplasmic CD79a (cCD79a), CD19, VpreB (CD179a), and sIgm, which are successive and essential for progression of B cells along their developmental pathway. Analysis of the immunophenotypes of 48 common ALL cases showed that the immunophenotypic patterns were highly heterogeneous, with the leukemic cell population differing from case to case. Through the comprehensive analysis of immunophenotypic patterns, the profiles of patient-specific composite leukemia cell populations could provide detailed information helpful for the diagnosis, therapeutic monitoring, and individualized therapies for common ALL.

Early Response to Dexamethasone as Prognostic Factor: Result from Indonesian Childhood WK-ALL Protocol in Yogyakarta

Early response to treatment has been shown to be an important prognostic factor of childhood acute lymphoblastic leukemia (ALL) patients in Western studies. We studied this factor in the setting of a low-income province in 165 patients treated on Indonesian WK-ALL-2000 protocol between 1999 and 2006. Poor early response, defined as a peripheral lymphoblasts count of ≥1000/μL after 7 days of oral dexamethasone plus one intrathecal methotrexate (MTX), occurred in 19.4% of the patients. Poor responders showed a higher probability of induction failures compared to good responders (53.1% versus 23.3%, P < 0.01), higher probability of resistant disease (15.6% versus 4.5%, P = 0.02), shorter disease-free survival (P = 0.034; 5-year DFS: 24.9% ± 12.1% versus 48.6% ± 5.7%), and shorter event-free survival (P = 0.002; 5-year EFS: 9.7% ± 5.3% versus 26.3% ± 3.8%). We observed that the percentage of poor responders in our setting was higher than reported for Western countries with prednisone or prednisolone as the steroids. The study did not demonstrate a significant additive prognostic value of early response over other known risk factors (age and white blood cell count) for DFS and only a moderately added value for EFS.

Role of cytotoxic therapy with hematopoietic stem cell transplantation in the treatment of pediatric acute lymphoblastic leukemia: update of the 2005 evidence-based review

Clinical research published since the first evidence-based review on the role of hematopoietic stem cell transplantation (SCT) in the treatment of pediatric acute lymphoblastic leukemia (ALL) is presented and critically evaluated in this update. Treatment recommendations are provided by an expert panel. Allogeneic SCT is recommended for children who: are in second complete remission (CR2) after experiencing an early marrow relapse for precursor-B ALL; experienced primary induction failure, but subsequently achieved a CR1; have T-lineage ALL in CR2; or have ALL in third or greater remission. Although the 2005 pediatric ALL evidence-based review (EBR) recommended allogeneic SCT for children with Philadelphia chromosome positive (Ph+) ALL in CR1, preliminary tyrosine kinase inhibitor (TKI) data demonstrate that early outcomes are comparable for allogeneic SCT and chemotherapy + imatinib. Based on the evidence, autologous SCT is not recommended for ALL in CR1. Allogeneic SCT is not recommended for: T-lineage ALL in CR1; mixed-lineage leukemia (MLL)+ ALL when it is the sole adverse risk factor; isolated central nervous system (CNS) relapse in precursor-B ALL. Based on expert opinion, allogeneic SCT may be considered for hypodiploid ALL and persistent minimal residual disease [corrected] (MRD) positivity in ALL in CR1 or greater, although these are areas that need further study. Treatment recommendations pertaining to various transplantation techniques are also provided, as are areas of needed future research.

Intermediate dose of imatinib in combination with chemotherapy followed by allogeneic stem cell transplantation improves early outcome in paediatric Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL): results of the Spanish Cooperative Group SHOP studies ALL-94, ALL-99 and ALL-2005

Philadelphia-chromosome acute lymphoblastic leukaemia (Ph+ ALL) is a subgroup of ALL with very high risk of treatment failure. We report here the results of the Sociedad Española de Hematología y Oncología Pediátricas (SEHOP/SHOP) in paediatric Ph+ ALL treated with intermediate-dose imatinib concurrent with intensive chemotherapy. The toxicities and outcome of these patients were compared with historical controls not receiving imatinib. Patients with Ph+ ALL aged 1-18years were enrolled in three consecutive ALL/SHOP trials (SHOP-94/SHOP-99/SHOP-2005). In the SHOP-2005 trial, imatinib (260mg/m(2) per day) was given on day-15 of induction. Allogeneic haematopoietic stem-cell transplantation (HSCT) from a matched related or unrelated donor was scheduled in first complete remission (CR1). Forty-three patients were evaluable (22 boys, median age 6·8years, range, 1·2-15). Sixteen received imatinib whereas 27 received similar chemotherapy without imatinib. Seventeen of 27 and 15 of 16 patients in the non-imatinib and imatinib cohort, respectively, underwent HSCT in CR1. With a median follow-up of 109 and 39months for the non-imatinib and imatinib cohorts, the 3-year event-free survival (EFS) was 29·6% and 78·7%, respectively (P=0·01). These results show that, compared to historical controls, intermediate dose of imatinib given concomitantly with chemotherapy and followed by allogeneic HSCT markedly improved early EFS in paediatric Ph+ ALL.

Dexamethasone versus prednisone for induction therapy in childhood acute lymphoblastic leukemia: a systematic review and meta-analysis

This systematic review and meta-analysis compared the efficacy and toxicity of dexamethasone (DEX) versus prednisone (PRED) for induction therapy in childhood acute lymphoblastic leukemia (ALL). We searched biomedical literature databases and conference proceedings for randomized controlled trials comparing DEX and PRED during induction therapy for childhood ALL. A total of eight studies were eligible for inclusion in this meta-analysis. DEX, in comparison with PRED, reduced events (that is, death from any cause, refractory or relapsed leukemia, or second malignancy; risk ratio (RR) 0.80; 95% confidence interval (CI), 0.68-0.94) and central nervous system relapse (RR 0.53; 95% CI, 0.44-0.65), but did not alter bone marrow relapse (RR 0.90; 95% CI, 0.69-1.18) or overall mortality (RR 0.91; 95% CI, 0.76-1.09). Patients receiving DEX had a higher risk of mortality during induction (RR 2.31; 95% CI, 1.46-3.66), neuro-psychiatric adverse events (RR 4.55; 95% CI, 2.45-8.46) and myopathy (RR 7.05; 95% CI, 3.00-16.58). There was no statistically significant difference in the risk of osteonecrosis, sepsis, fungal infection, diabetes or pancreatitis. DEX in induction therapy for children with ALL is more efficacious than PRED. However, DEX is also associated with more toxicity, and currently it remains unclear whether short-term superiority of DEX will also result in better overall survival.

Treatment including anthracyclines versus treatment not including anthracyclines for childhood cancer

BACKGROUND

One of the most important adverse effects of anthracyclines is cardiotoxicity. A well-informed decision on the use of anthracyclines in the treatment of childhood cancers should be based on evidence regarding both antitumour efficacy and cardiotoxicity.

OBJECTIVES

To compare antitumour efficacy of treatment including or not including anthracyclines in children with childhood cancer.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2010, Issue 2), MEDLINE (1966 to March 2010) and EMBASE (1980 to March 2010). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing trials databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing treatment of any type of childhood cancer with and without anthracyclines and reporting outcomes concerning antitumour efficacy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed the study selection, risk of bias assessment and data extraction.

MAIN RESULTS

We identified RCTs for six types of tumour: acute lymphoblastic leukaemia (ALL) (three trials; 912 children), Wilms' tumour (one trial; 316 children), rhabdomyosarcoma/undifferentiated sarcoma (one trial; 413 children), Ewing's sarcoma (one trial; 94 children), non-Hodgkin lymphoma (one trial; 284 children) and hepatoblastoma (one trial; 255 children). All studies had methodological limitations. For ALL no evidence of a significant difference in antitumour efficacy was identified in the meta-analyses, but in most individual studies there was a suggestion of better antitumour efficacy in patients treated with anthracyclines. For both Wilms' tumour and Ewing's sarcoma a significant difference in event-free and overall survival in favour of treatment with anthracyclines was identified, although for Wilms' tumour the significant difference in overall survival disappears with long-term follow-up. For rhabdomyosarcoma/undifferentiated sarcoma, non-Hodgkin lymphoma and hepatoblastoma no difference in antitumour efficacy between the treatment groups was identified. Clinical cardiotoxicity was evaluated in three RCTs: no significant difference between both treatment groups was identified, but in all individual studies there was a suggestion of a lower rate of clinical cardiotoxicity in patients who did not receive anthracyclines. None of the studies evaluated asymptomatic cardiac dysfunction. For other childhood cancers no RCTs were identified.

AUTHORS' CONCLUSIONS

At the moment no evidence from RCTs is available which underscores the use of anthracyclines in ALL. However, "no evidence of effect", as identified in this review, is not the same as "evidence of no effect". For Wilms' tumour, rhabdomyosarcoma/undifferentiated sarcoma, Ewing's sarcoma, non-Hodgkin lymphoma and hepatoblastoma only one RCT was available and, therefore, no definitive conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours. For other childhood cancers no RCTs were identified and therefore, no conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours.

Treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia

The presence of the Philadelphia chromosome is a poor prognosis factor in acute lymphoblastic leukemia (ALL), in both children and adults. Using molecular techniques of the gen bcr/abl, it is possible to detect the abnormality, in up to the 40% of adult patients. The unsatisfactory results with conventional chemotherapy schemes have determined the intensification of the treatments and the consideration of allogenic bone marrow transplants as the best therapeutic instance. The development of tyrosine kinase inhibitors have become a therapeutic improvement in the treatment of Philadelphia chromosome-positive ALL, being combined with chemotherapy schemes, only in a selected group of patients, even in therapeutic programs that include transplant.

Temporal changes in the incidence and pattern of central nervous system relapses in children with acute lymphoblastic leukaemia treated on four consecutive Medical Research Council trials, 1985-2001

Despite the success of contemporary treatment protocols in childhood acute lymphoblastic leukaemia (ALL), relapse within the central nervous system (CNS) remains a challenge. To better understand this phenomenon, we have analysed the changes in incidence and pattern of CNS relapses in 5564 children enrolled on four successive MRC-ALL trials between 1985 and 2001. Changes in the incidence and pattern of CNS relapses were examined and the relationship with patient characteristics assessed. Factors affecting post-relapse outcome were determined. Overall, relapses declined by 49%. Decreases occurred primarily in non-CNS and combined relapses with a progressive shift towards later (≥30 months from diagnosis) relapses (p<0·0001). Although isolated CNS relapses declined, the proportional incidence and timing of relapse remained unchanged. Age and presenting white cell count were risk factors for CNS relapse. On multivariate analysis, the time to relapse and the trial period influenced post-relapse outcomes. Relapse trends differed within biological subtypes. In ETV6-RUNX1 ALL, relapse patterns mirrored overall trends while in High Hyperdiploidy ALL, these appear to have plateaued over the latter two trial periods. Intensive systemic and intrathecal chemotherapy have decreased the overall CNS relapse rates and changed the patterns of recurrence. The heterogeneity of therapeutic response in the biological subtypes suggests room for further optimisation using currently available chemotherapy.

A dyad of lymphoblastic lysosomal cysteine proteases degrades the antileukemic drug L-asparaginase

l-Asparaginase is a key therapeutic agent for treatment of childhood acute lymphoblastic leukemia (ALL). There is wide individual variation in pharmacokinetics, and little is known about its metabolism. The mechanisms of therapeutic failure with l-asparaginase remain speculative. Here, we now report that 2 lysosomal cysteine proteases present in lymphoblasts are able to degrade l-asparaginase. Cathepsin B (CTSB), which is produced constitutively by normal and leukemic cells, degraded asparaginase produced by Escherichia coli (ASNase) and Erwinia chrysanthemi. Asparaginyl endopeptidase (AEP), which is overexpressed predominantly in high-risk subsets of ALL, specifically degraded ASNase. AEP thereby destroys ASNase activity and may also potentiate antigen processing, leading to allergic reactions. Using AEP-mediated cleavage sequences, we modeled the effects of the protease on ASNase and created a number of recombinant ASNase products. The N24 residue on the flexible active loop was identified as the primary AEP cleavage site. Sole modification at this site rendered ASNase resistant to AEP cleavage and suggested a key role for the flexible active loop in determining ASNase activity. We therefore propose what we believe to be a novel mechanism of drug resistance to ASNase. Our results may help to identify alternative therapeutic strategies with the potential of further improving outcome in childhood ALL.

Indications for hematopoietic cell transplantation in acute leukemia

Based on available data, all adults with AML under age 60 years with matched siblings should be considered for allogeneic transplantation in first remission, except for those with favorable risk cytogenetics and possibly those whose disease has normal cytogenetics and is FLT3/ITD negative and NPM1 positive. Patients with matched siblings not transplanted in first remission should be followed closely so that transplantation in early first relapse can be considered. Those without matched siblings should receive a MUD transplant in first CR if they have higher risk disease. All others should receive standard chemotherapy and consider a matched unrelated transplant or autologous transplant, should they relapse. RIC allogeneic transplantation using either a matched family member or a MUD can be considered for patients age 60 years or greater with AML in second or subsequent remission, or AML in first remission with intermediate or high risk disease.

Treatment including anthracyclines versus treatment not including anthracyclines for childhood cancer

BACKGROUND

One of the most important adverse effects of anthracyclines is cardiotoxicity. A well-informed decision on the use of anthracyclines in the treatment of different types of childhood cancer should be based on the available evidence on both antitumour efficacy and cardiotoxicity.

OBJECTIVES

To compare antitumour efficacy of treatment including or not including anthracyclines in children with childhood cancer.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2006, issue 4), MEDLINE (1966 to January 2007) and EMBASE (1980 to January 2007). In addition, we searched reference lists of relevant articles, conference proceedings and ongoing trials databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing treatment of any type of childhood cancer with and without anthracyclines and reporting outcomes concerning antitumour efficacy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed the study selection, quality assessment and data-extraction.

MAIN RESULTS

We identified RCTs for 5 types of tumour: acute lymphoblastic leukaemia (ALL) (n=3; 912 children), Wilms' tumour (n=1; 316 children), rhabdomyosarcoma/undifferentiated sarcoma (n=1; 413 children), Ewing's sarcoma (n=1; 94 children), and non-Hodgkin lymphoma (n=1; 284 children). All studies had methodological limitations. For ALL no evidence of a significant difference in antitumour efficacy was identified in the meta-analyses, but in most individual studies there was a suggestion of better antitumour efficacy in patients treated with anthracyclines. For both Wilms' tumour and Ewing's sarcoma a significant difference in survival in favour of treatment with anthracyclines was identified. The hazard ratios for overall and event-free survival in Wilms' tumour were 1.85 (95% CI 1.09 to 3.15) and 2.21 (95% CI 1.44 to 3.40), respectively. For patients with Ewing's sarcoma only descriptive results were available (P = 0.02 for overall survival and P = 0.01 for event-free survival). For both rhabdomyosarcoma/undifferentiated sarcoma and non-Hodgkin lymphoma no difference in antitumour efficacy between the treatment groups was identified. Clinical cardiotoxicity was evaluated in 3 RCTs. No significant difference between both treatment groups was identified, but in all individual studies there was a suggestion of a lower rate of clinical cardiotoxicity in patients who did not receive anthracyclines. None of the studies evaluated asymptomatic cardiac dysfunction. For other childhood cancers no RCTs were identified.

AUTHORS' CONCLUSIONS

At the moment no evidence from RCTs is available which underscores the use of anthracyclines in ALL. However, it should be noted that "no evidence of effect", as identified in this review, is not the same as "evidence of no effect". For Wilms' tumour, rhabdomyosarcoma/undifferentiated sarcoma, Ewing's sarcoma, and non-Hodgkin lymphoma only 1 RCT was available and therefore, no definitive conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours. For other childhood cancers no RCTs were identified and therefore, no conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours. More high quality research is needed.

Impact of age, leukocyte count and day 21-bone marrow response to chemotherapy on the long-term outcome of children with philadelphia chromosome-positive acute lymphoblastic leukemia in the pre-imatinib era: results of the FRALLE 93 study

BACKGROUND

We explored the heterogeneity of philadelphia chromosome-positive acute lymphoblastic leukemia (Ph1-ALL) in a study of the effect of early features on prognosis in children. Here we report the long-term results of the FRALLE 93 study conducted in the era before the use of tyrosine kinase inhibitors.

METHODS

Between 1993 and 1999, 36 children with Ph1-ALL were enrolled into the FRALLE 93 protocol. After conventional four-drug induction, children were stratified by availability of an HLA-matched sibling.

RESULTS

Complete remission (CR) was observed in 26 children (72%), of which 13 underwent allogeneic bone marrow transplantation (BMT). Thirty-one children were good responders to prednisone, defined on day 8, and 21 were good responders to chemotherapy, defined by day-21 bone marrow (M1). Overall five-year disease-free survival (DFS) was 42 +/- 9.7%. Based on multivariate analysis, two groups showed marked differences in five-year outcome: children with age<10, leukocyte count <100,000/mm3 and day-21 M1 marrow had a more favorable prognosis (14 pts: 100% CR, event free survival [EFS]: 57%, overall survival [OS]: 79%), than the high-risk group (22 patients: 55% CR, EFS: 18%, OS: 27%) (p < 0.005). We also observed a non statistically significant difference (p = 0.14) in outcome between these groups for transplanted patients (5-year DFS: 83 +/- 14% and 33 +/- 15%, respectively).

CONCLUSION

Age, leukocyte count and early response to treatment defined by the D21 bone marrow response provide an accurate model for outcome prediction. The combination of available tools such as minimal residual disease assessment with determination of these simple factors could be useful for refining indications for BMT in the current era of tyrosine-kinase inhibitor-based therapy.

Recent advances in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia

The advent of imatinib, a selective inhibitor of the ABL tyrosine kinase, has revolutionized the treatment of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Combined with chemotherapy, imatinib exerts remarkable efficacy in patients with newly diagnosed disease with a complete remission (CR) rate of 95% and a survival rate of 55% at 3 years. Profound eradication of leukemia cells not only provides patients with a better chance for receiving allogeneic hematopoietic stem cell transplantation during first CR but also contributes to durable CR even without transplantation. Despite such improvement, however, relapse does occur, mainly owing to acquisition of resistance. Growing comprehension of the molecular mechanisms of resistance to imatinib has led to the development of novel BCR-ABL inhibitors that yield higher affinity for BCR-ABL and/or potent inhibitory activity against other target molecules such as SRC family kinases. The second-generation ABL kinase inhibitors, namely dasatinib and nilotinib, are already showing clinical activity in patients with imatinib-resistant Ph+ ALL, and other novel agents are undergoing preclinical and early clinical evaluation. Further improvement in treatment results will be achieved by identifying each patient's disease profile based on information obtained before and during treatment and by optimizing subsequent treatment accordingly.

Familial T-cell non-Hodgkin lymphoma caused by biallelic MSH2 mutations

Familial non-Hodgkin lymphoma (NHL) is rare and in most cases, no underlying cause is identifiable. We report homozygous truncating mutations in the mismatch repair gene MSH2 (226C-->T; Q76X) in three siblings who each developed T-cell NHL in early childhood. All three children had hyperpigmented and hypopigmented skin lesions. Constitutional biallelic MSH2 mutations have previously been reported in five individuals, all of whom developed malignancy in childhood. Familial lymphoma has not been reported in this context or in association with biallelic mutations in the other mismatch repair genes MLH1, MSH6 or PMS2. In addition, hypopigmented skin lesions have not previously been reported in biallelic MSH2 carriers. Our findings therefore expand the spectrum of phenotypes associated with biallelic MSH2 mutations and identify a new cause of familial lymphoma. Moreover, the diagnosis has important management implications as it allows the avoidance of chemotherapeutic agents likely to be ineffective and mutagenic in the proband, and the provision of cascade genetic testing and tumour screening for relatives.

Allogeneic transplantation for childhood ALL

More than 80% of children with ALL are now cured with chemotherapy without need for transplantation. This remarkable progress is the result of serial large-scale randomized clinical trials incorporating improvements in risk group assignment, administration of risk-adjusted therapy and intensified therapy for children with high-risk disease. Despite these advances, significant numbers of children still die of relapsed or refractory ALL, as ALL is the most frequent malignancy of childhood. This review focuses on the appropriate use of transplantation for children with ALL and optimization of transplant procedures to improve survival and reduce late consequences of therapy.

Leukaemic infiltration of the mandible in a young girl

BACKGROUND

This report presents a case of leukaemic infiltration of the mandible in a 10-year-old female of Sudanese extraction.

CASE REPORT

The patient was in remission from acute lymphoblastic leukaemia when she presented with pain localized to the alveolar ridge overlying the unerupted lower right second permanent molar. Two days later, she developed right inferior alveolar nerve paraesthesia. Radiographic imaging demonstrated cortical line absence around the developing lower right second and third permanent molars, and distal displacement of the lower right third molar. In addition, the cortical outline of the right inferior dental canal lacked clarity. Biopsy confirmed leukaemia recurrence demonstrating the Philadelphia chromosome. Tailored chemotherapy was commenced, and a bone marrow transplant was carried out 12 weeks later. At 6-month dental review, the patient remained exceptionally well with no bone pain and normal sensation in the right lower lip.

CONCLUSION

The importance of regular and long-term dental examination of patients with leukaemia is discussed.

Allogeneic bone marrow transplantation in first remission for children with ultra-high-risk features of acute lymphoblastic leukemia: A children's oncology group study report

The prognosis for childhood acute lymphoblastic leukemia (ALL) has improved dramatically over the past quarter of a century. Despite improvements in the treatment of childhood ALL, relapse still occurs in 20%-30% of patients. Although many of these relapses occur in the "standard-risk" patients, approximately 10% of these patients present at diagnosis with clinical and biological features that identify them as having a very high risk of relapse. Children (2 months to 21 years) with > or =1 ultra-high-risk feature (UHRF) of ALL in first remission treated on a frontline Children's Cancer Group (CCG) ALL study with a matched family allogeneic donor were eligible for study entry onto CCG-1921 and an allogeneic bone marrow transplant (AlloBMT). Each patient received fractionated total body irradiation (1200 cGy) and cyclophosphamide (120 mg/kg) conditioning therapy followed by unmobilized BM from a matched family donor. Graft-versus-host disease (GVHD) prophylaxis consisted of methotrexate and cyclosporin. Twenty-nine patients with a median age of 8.7 years with UHRF ALL in first complete remission (CR1) received an AlloBMT from a family member. The incidence of grade II-IV acute GVHD was 20.7% and the incidence of chronic GVHD was 3.7%. AlloBMT conditioning regimen was well tolerated and only 1 patient (3%) had treatment-related mortality. Ten patients (35%) died due to progressive disease. The 5-year event-free survival (EFS) for all patients was 58.6% and patients without cytogenetic abnormalities had a 5-year EFS of 77.8%. The 5-year EFS rates for infants and non-infants were 20.0% and 66.7% (log-rank test, P = .01), respectively. Patients with Philadelphia chromosome-positive ALL had a 5-year EFS of 66.7%. The children with UHRF of ALL may benefit from AlloBMT in CR1, especially patients with primary induction failure and Philadelphia chromosome-positive ALL. Randomized prospective cooperative group studies are required to establish the role of allogeneic hematopoietic stem cell transplantation versus intensive chemotherapy in children with UHRF ALL in CR1.

Comparison of intensive chemotherapy, allogeneic, or autologous stem-cell transplantation as postremission treatment for children with very high risk acute lymphoblastic leukemia: PETHEMA ALL-93 Trial

PURPOSE

The optimal postremission therapy for children with very high-risk (VHR) acute lymphoblastic leukemia (ALL) is not well established. This randomized trial compared three options of postremission therapy: chemotherapy and allogeneic or autologous stem-cell transplantation (SCT).

PATIENTS AND METHODS

All 106 VHR-ALL patients received induction with five drugs followed by intensification with three cycles of chemotherapy. Patients in complete remission (CR) with an HLA-identical family donor were assigned to allogeneic SCT (n = 24) and the remaining were randomly assigned to autologous SCT (n = 38) or to delayed intensification followed by maintenance chemotherapy up to 2 years in CR (n = 38).

RESULTS

Overall, 100 patients achieved CR (94%). With a median follow-up of 6.5 years, 5-year disease-free survival (DFS) and overall survival (OS) probabilities were 45% (95% CI, 37% to 54%) and 48% (95% CI, 40% to 57%), respectively. The three groups were comparable in the main pretreatment ALL characteristics. Intention-to-treat analysis showed no differences for donor versus no donor in DFS (45%; 95% CI, 27% to 65% v 45%; 95% CI, 37% to 55%) and OS (48%; 95% CI, 30% to 67% v 51%; 95% CI, 43% to 61%), as well as for autologous SCT versus chemotherapy comparisons (DFS: 44%; 95% CI, 29% to 60% v 46%; 95% CI, 32% to 62%; OS: 45%; 95% CI, 31% to 62% v 57%; 95% CI, 43% to 73%). No differences were found within the different subgroups of ALL and neither were differences observed when the analysis was made by treatment actually performed.

CONCLUSION

This study failed to prove that, when a family donor is available, allogeneic SCT produces a better outcome than autologous SCT or chemotherapy in children with VHR-ALL.

Imatinib combined chemotherapy for Philadelphia chromosome-positive acute lymphoblastic leukemia: major challenges in current practice

The prognosis of Philadelphia chromosome-positive (Ph+) and/or BCR-ABL-positive acute lymphoblastic leukemia (ALL) is extremely poor, and for decades allogeneic hematopoietic stem cell transplantation (HSCT) has been considered the only option for a cure. However, the treatment for Ph+ ALL has been rapidly changing since imatinib, a selective inhibitor of the ABL tyrosine kinase, was introduced. Earlier clinical trials in which a moderate anti-leukemic effect of imatinib monotherapy was demonstrated have prompted investigators to explore the combination of imatinib and chemotherapy. The results of multiple studies indicate that chemotherapy combined with imatinib is well tolerated, induces complete hematological remission in almost every patient with newly diagnosed Ph+ ALL, and molecular remission in more than half of the cases. Future clinical studies need to focus on how imatinib can be incorporated into chemotherapy more effectively by determining the optimal dosage of imatinib, the optimal combinational schedule, and the role of allogeneic HSCT.

High complete remission rate and promising outcome by combination of imatinib and chemotherapy for newly diagnosed BCR-ABL-positive acute lymphoblastic leukemia: a phase II study by the Japan Adult Leukemia Study Group

PURPOSE

A novel therapeutic approach is urgently needed for BCR-ABL-positive acute lymphoblastic leukemia (ALL). In this study, we assessed the efficacy and feasibility of chemotherapy combined with imatinib.

PATIENTS AND METHODS

A phase II study of imatinib-combined chemotherapy was conducted for newly diagnosed BCR-ABL-positive ALL in adults. Eighty patients were entered into the trial between September 2002 and January 2005.

RESULTS

Remission induction therapy resulted in complete remission (CR) in 77 patients (96.2%), resistant disease in one patient, and early death in two patients, as well as polymerase chain reaction negativity of bone marrow in 71.3%. The profile and incidence of severe toxicity were not different from those associated with our historic chemotherapy-alone regimen. Relapse occurred in 20 patients after median CR duration of 5.2 months. Allogeneic hematopoietic stem-cell transplantation (HSCT) was performed for 49 patients, 39 of whom underwent transplantation during their first CR. The 1-year event-free and overall survival (OS) rates were estimated to be 60.0%, and 76.1%, respectively, which were significantly better than those for our historic controls treated with chemotherapy alone (P < .0001 for both). Among the current trial patients, the probability for OS at 1 year was 73.3% for those who underwent allogeneic HSCT, and 84.8% for those who did not.

CONCLUSION

Our results demonstrated that imatinib-combined regimen is effective and feasible for newly diagnosed BCR-ABL-positive ALL. Despite a relatively short period of observation, a major potential of this treatment is recognized. Longer follow-up is required to determine its overall effect on survival.

Philadelphia positive acute lymphoblastic leukaemia of childhood

On current chemotherapeutic regimens, children with Philadelphia positive acute lymphoblastic leukaemia show a heterogeneous response to treatment. A few respond quickly to treatment and achieve long-term remission. Some fail to achieve remission after induction and the majority respond slowly to treatment. Relapse on treatment is common and remission is sustained in a proportion of cases only after allogeneic stem cell transplantation (allo-SCT). The use of imatinib along with conventional cytoreductive therapy, prior to allo-SCT appears to be the most promising strategy. The future lies in the molecular evaluation of response to treatment and combination targeted chemotherapy.