Value of high-dose cytarabine during interval therapy of a Berlin-Frankfurt-Munster-based protocol in increased-risk children with acute lymphoblastic leukemia and lymphoblastic lymphoma: results of the European Organization for Research and Treatment of Cancer 58881 randomized phase III trial

Survival and prognostic analysis of T-cell lymphoblastic lymphoma patients treated with dose-adjusted BFM-90 regimen

We aimed to investigate the long-term prognosis and prognostic factors of T-cell lymphoblastic lymphoma (T-LBL) patients who received dose-adjusted Berlin–Frankfurt–Münster (BFM)-90 regimen as first-line therapy in our center. A total of 145 T-LBL patients who underwent first-line dose-adjusted BFM-90 was retrospectively reviewed. Conditional survival analysis was used to evaluate the long-term prognosis of patients. Receiver operating characteristic (ROC) curve was applied to determine the optimal cut-off value for neutrophil-to-lymphocyte ratio (NLR). Estimated 3-year overall survival (OS) and progression-free survival (PFS) rates for overall were 66.8% and 58.4%, respectively. Conditional survival analysis showed that for patients having survived 3 and 5 years or more after the completion of the treatment, the estimated subsequent 3-year OS thereafter increased to 85.7% and 94.3, respectively. Patients receiving consolidation APBSCT (Autologous peripheral blood stem cell transplantation) after BFM-90 regimen had superior 3-year OS than those with non-APBSCT (79.1% vs. 33.4%, p<0.001). We also discovered that baseline NLR ≥4.95 was negatively associated with OS (HR=2.75, 95% CI 1.55-4.89, p=0.015) and PFS (HR=2.07, 95% CI 1.25-4.96, p=0.021) via multivariable analysis. Conclusions: The survival probability of T-LBL patients treated with first-line dose-adjusted BFM-90 has improved significantly as patients have survived for every additional year. The addition of consolidation APBSCT following dose-adjusted BFM-90 therapy bring further survival benefits for those patients. Baseline NLR ≥4.95 was an independent risk factor for T-LBL patients in our study.

Late isolated central nervous system relapse in childhood B-cell acute lymphoblastic leukemia treated with intensified systemic therapy and delayed reduced dose cranial radiation: A report from the Children's Oncology Group study AALL02P2

BACKGROUND

Patients with late, ≥18 months postdiagnosis, isolated central nervous relapse (iCNS-R) of B-acute lymphoblastic leukemia (ALL) have excellent outcomes with chemotherapy plus cranial radiotherapy, with 5-year overall survival (OS) approaching 80% in POG 9412. Subsequent relapse and radiation-related morbidity remain the causes of treatment failure and long-term sequelae. COG AALL02P2 aimed to maintain outcomes in patients with late iCNS-R using intensified chemotherapy and a decrease in cranial irradiation from 1800 to 1200 cGy.

PROCEDURES

COG AALL02P2 enrolled 118 eligible patients with B-cell ALL (B-ALL) and late iCNS-R who received intensified systemic therapy, triple intrathecal chemotherapy, and 1200 cGy cranial irradiation delivered at 12 months, with maintenance chemotherapy continuing until 104 weeks postdiagnosis.

RESULTS

The 3-year event-free survival (EFS) and OS were 64.3% ± 4.5% and 79.6% ± 3.8%, with 46.1% (18/39) of second relapses including the CNS. Of the 112 patients who completed therapy, 78 received protocol-specified radiation. Study enrollment was closed after interim monitoring analysis showed inferior EFS compared to POG 9412. Patients with initial NCI standard-risk classification fared better than high-risk patients.

CONCLUSIONS

COG AALL02P2 showed inferior EFS but similar OS compared to POG 9412. Limitations included a small sample size, more intensive prior therapies, and a significant number of patients (34/118, 29%) who did not receive protocol-directed radiation due to early relapse prior to 1 year or did not otherwise follow the treatment plan. New approaches are needed to improve outcome for these patients and determine the optimal timing and dose of cranial radiation in the treatment of iCNS-R.

Lymphoma in Adolescents and Young Adults: Current Perspectives

Lymphomas in adolescents and young adults represent approximately one quarter of all cancers in this age group. Historically, adolescent and young adult cancer patients represent a unique population with diverging issues surrounding psychosocial hardships/barriers, economics, and lack of standardization of therapeutic approaches.Furthermore, the biologic differences within the adolescent and young adult population seen in various lymphoma subtypes likely play a role in overall outcomes for this group. Without an organized approach to clinical and translational research for adolescent and young adult patients within specialized treatment centers, this population may continue to experience inferior results. Here we look at the current perspectives of adolescent and young adult lymphomas with respect to disease biology, clinical characteristics, treatment, and prognosis of this unique lymphoma population.

NHL in adolescents and young adults: A unique population

Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid malignancies with high incidence in adolescents and young adults (AYAs). The most common diseases include diffuse large B-cell lymphoma, anaplastic large cell lymphoma, Burkitt lymphoma, lymphoblastic lymphoma, and primary mediastinal large B-cell lymphoma. In comparison to younger children and adults, AYAs (15-39 years) with NHL present a specific set of challenges including variations in tumor biology, inconsistent treatment, pharmacodynamics, and psychosocial barriers. While survival of AYAs with NHL has improved, cure rates remain suboptimal. Incorporation of novel agents into pediatric-inspired treatment regimens specifically designed for NHL in AYAs has led to improved outcomes. Consideration of AYAs as a distinct population in the diagnosis and treatment of NHL is encouraged.

Factors associated with a prolonged hospital stay during induction chemotherapy in newly diagnosed high risk pediatric acute lymphoblastic leukemia

BACKGROUND

High Risk (HR) or Very High Risk (VHR) acute lymphoblastic leukemia (ALL) treated with 4 drug induction chemotherapy is often associated with adverse events. The aim of this study was to identify risk factors associated with a prolonged inpatient length of stay LOS during induction chemotherapy.

PROCEDURE

Data from patients (N = 73) (age<21 years) was collected through a retrospective chart review. Univariable and multivariable logistic regression was used to test for statistical significance. The overall survival and disease (leukemia)-free survival were analyzed using the Kaplan-Meier method and log-rank test.

RESULTS

Of the 73 patients, 42 (57%) patients were discharged on day 4 of induction (short LOS, group A), while 31 (43%) patients (group B) experienced a prolonged LOS or an ICU stay (16 ± 27.7 days, median hospital stay = 8 days vs 4 days (group A), p = 0.02) due to organ dysfunction, infectious or metabolic complications. Group B patients were more likely to have a lower platelet count, serum bicarbonate, and a higher blood urea nitrogen (BUN) on day 4 of treatment (OR = 4.52, 8.21, and 3.02, respectively, p < 0.05). Multivariable analysis identified low serum bicarbonate (p = 0.002) and a platelet count<20,000/μL (p = 0.02) on day 4 of induction to be predictive of a prolonged LOS. Twenty six (group A (n = 16, 36%) and B (n = 11, 35%), p = 0.8) patients experienced unplanned admissions, within 30 days of discharge.

CONCLUSIONS

A significant proportion of newly diagnosed HR or VHR pediatric ALL patients experience a prolonged LOS and unplanned re-admissions. Aggressive discharge planning and close follow up is indicated in this cohort of patients.

Neurotoxicity after high-dose methotrexate (MTX) is adequately explained by insufficient folinic acid rescue

PURPOSE

To challenge the view that the dose of folinic acid rescue after high-dose methotrexate (MTX) has no significance in the prevention of neurotoxicity and to present the minority view that neurotoxicity can be prevented by an adequate dose of folinic acid, without compromising treatment results. Several fallacies that led to the misunderstanding of post MTX neurotoxicity are presented.

METHODS

Data mining using search engines was used to find relevant publications, and an e-mail survey of more than 60 authors of articles in this field was performed. All relevant articles identified were read in their entirety.

RESULTS

Examples of clinical studies with neurotoxicity following inadequate rescue are given. Some studies demonstrated no neurotoxicity when adequate doses of folinic acid rescue were started 24-36 h after the start of HDMTX rescue even after mega doses of MTX. Rescue started after 42 h was associated with neurotoxicity except in patients with low serum MTX levels after 24 and 36 h. ALL protocols with neurotoxicity, especially BFM-like protocols, are presented. Protocol is reported in which single protocol changes prevented neurotoxicity.

CONCLUSIONS

From the published data, when folinic acid rescue is given in a sufficiently high enough dose and is started 24-36 h after the beginning of the methotrexate exposure, and virtually all forms of post MTX neurotoxicity can be prevented without compromising therapeutic results.

Prognostic Impact of Intensified Maintenance Therapy on Children With Advanced Lymphoblastic Lymphoma: A Report From the Japanese Pediatric Leukemia/Lymphoma Study Group ALB-NHL03 Study

BACKGROUND

Childhood advanced lymphoblastic lymphoma (LBL) has a favorable outcome with an event-free survival (EFS) rate of over 80% in response to treatment strategies for acute lymphoblastic leukemia (ALL). However, no progress has been made in this outcome over the past 10 years.

PROCEDURE

We conducted the first nationwide prospective study of childhood advanced LBL to assess the efficacy and safety of ALL-directed therapy with an intensified maintenance phase. We omitted local radiotherapy including prophylactic cranial radiotherapy except for patients with initial central nervous system disease. The total duration of the treatment was 24 months.

RESULTS

For the 136 patients analyzed in this study, 5-year overall survival (OS) was 82.9% and 5-year EFS was 77.9%. Thirty events were observed and 14 occurred before the initiation of intensified maintenance phase. Of 14 events, nine were observed as mediastinal enlargement. There was no significant difference in outcome when stratified according to gender or by immunophenotype. The 5-year EFS according to clinical stage in patients with T-cell LBL (T-LBL) was 70.6% for stage III and 88.9% for stage IV (P = 0.037).

CONCLUSIONS

Our first nationwide study provided about 80% cure rate with only one case of toxic death in childhood advanced LBL. However, our intensified maintenance therapy could not improve the survival outcome. There was a trend of better EFS in Japanese patients with T-LBL stage IV than T-LBL stage III.

Guideline on the prevention of secondary central nervous system lymphoma: British Committee for Standards in Haematology

The guideline group was selected to be representative of UK-based medical experts. Ovid MEDLINE, EMBASE and NCBI Pubmed were searched systematically for publications in English from 1980 to 2012 using the MeSH subheading 'lymphoma, CNS', 'lymphoma, central nervous system', 'lymphoma, high grade', 'lymphoma, Burkitt's', 'lymphoma, lymphoblastic' and 'lymphoma, diffuse large B cell' as keywords, as well as all subheadings. The writing group produced the draft guideline, which was subsequently revised by consensus by members of the Haemato-oncology Task Force of the British Committee for Standards in Haematology (BCSH). The guideline was then reviewed by a sounding board of ~50 UK haematologists, the BCSH and the British Society for Haematology (BSH) Committee and comments incorporated where appropriate. The 'GRADE' system was used to quote levels and grades of evidence, details of which can be found in Appendix I. The objective of this guideline is to provide healthcare professionals with clear guidance on the optimal prevention of secondary central nervous system (CNS) lymphoma. The guidance may not be appropriate to patients of all lymphoma sub-types and in all cases individual patient circumstances may dictate an alternative approach. Acronyms are defined at time of first use.

Second neoplasm in children treated in EORTC 58881 trial for acute lymphoblastic malignancies: low incidence of CNS tumours

BACKGROUND

Intensive chemotherapy has markedly improved the survival of children with acute lymphoblastic leukaemia (ALL) or lymphoblastic lymphoma (LL). Evaluation of late effects and analysis of factors contributing to their occurrence has become of major importance. Second neoplasm (SN) belongs to the most severe late events.

PROCEDURE

We report the incidence of SN which occurred in patients recruited in EORTC trial 58881 for children with ALL or LL. The front-line treatment regimen was adapted from the BFM protocol, but did not include cranial radiotherapy, even in patients with initial involvement of the central nervous system. A total of 2,216 patients were recruited, of whom 2,136 achieved complete remission (CR).

RESULTS

At a median follow-up of 7.5 years, 22 (1%) patients developed a SN: 20 during or after completion of front-line therapy and 2 in second CR, after relapse treatment including haematopoietic stem cell transplantation (HSCT). Ten patients developed acute myeloblastic leukaemia. Only one SN, a glioblastoma, was a brain tumour. Other SN were: two Hodgkin lymphomas, one non-Hodgkin lymphoma, two thyroid cancers, one osteosarcoma, two soft tissue sarcomas, one Ewing sarcoma, one cutaneous histiocytosis and one peritoneal carcinomatosis. The cumulative incidences of SN at 5, 8 and 13 years after registration were 0.8% (SE 0.2%), 1.0% (SE 0.2%) and 3.0% (SE 1.9%), respectively.

CONCLUSION

The overall incidence rate of SN is comparable to that reported previously. In spite of short follow-up time, the low incidence of brain tumours might be related to the omission of cranial radiotherapy.

Minimal residual disease-based augmented therapy in childhood acute lymphoblastic leukemia: a report from the Japanese Childhood Cancer and Leukemia Study Group

BACKGROUND

The majority of minimal residual disease (MRD)-positive patients with acute lymphoblastic leukemia (ALL) have poor outcomes. The ALL2000 study was performed to evaluate the efficacy of augmented chemotherapy based on MRD-restratification in childhood ALL.

PROCEDURE

Between 2000 and 2004, 305 eligible patients with precursor B or T-cell ALL were enrolled in the ALL2000 study. The ALL941-based therapy protocol utilized PCR MRD assays using Immunoglobulin and T-cell receptor gene rearrangements. They were initially stratified into three risk-groups according to leukocyte count and age, and MRD levels were measured at weeks 5 (TP1) and 12 (TP2) for a second stratification. From week 14, patients with MRD levels ≥ 10(-3) received an increase in therapy (one risk group higher), while the remainder continued to receive the initial risk-adapted therapy.

RESULTS

The overall 5-year event-free survival (EFS) rate for ALL2000 was 79.7 ± 2.4%. MRD stratification was feasible for 234 of 301 patients (77%) who achieved complete remission. The EFS rate of the MRD stratifiable (MRD) group was 82.5 ± 2.6%, considerably superior to the 74.7 ± 5.7% of MRD non-stratifiable (Non-MRD) group (P = 0.084) and the 74.4 ± 2.1% for ALL 941 (P = 0.012). MRD-positive patients at TP2 showed inferior outcomes as compared with MRD-negative cases, but the difference did not reach a statistically significant level in any risk groups or immunophenotypes.

CONCLUSIONS

These results suggest that augmented therapy for MRD-positive patients at TP2 contributed to better outcomes of the ALL2000 study.

Prognostic significance of the initial cerebro-spinal fluid (CSF) involvement of children with acute lymphoblastic leukaemia (ALL) treated without cranial irradiation: results of European Organization for Research and Treatment of Cancer (EORTC) Children Leukemia Group study 58881

AIM OF THE STUDY

To evaluate the prognostic significance of the initial cerebro-spinal fluid (CSF) involvement of children with ALL enrolled from 1989 to 1996 in the EORTC 58881 trial.

PATIENTS AND METHODS

Patients (2025) were categorised according to initial central nervous system (CNS) status: CNS-1 (CNS negative, n=1866), CNS-2 (<5 leucocytes/mm(3), CSF with blasts, n=50), CNS-3 (CNS positive, n=49), TLP+ (TLP with blasts, n=60). CNS-directed therapy consisted in intravenous (i.v.) methotrexate (5 g/sqm) in 4-10 courses, and intrathecal methotrexate injections (10-20), according to CNS status. Cranial irradiation was omitted in all patients.

RESULTS

In the CNS1, TLP+, CNS2 and CNS3 group the 8-year EFS rate (SE%) was 69.7% (1.1%), 68.8% (6.2%), 71.3% (6.5%) and 68.3% (6.2%), respectively. The 8-year incidence of isolated CNS relapse (SE%) was 3.4% (0.4%), 1.7% (1.7%), 6.1% (3.5%) and 9.4% (4.5%), respectively, whereas the 8-year isolated or combined CNS relapse incidence was 7.6% (0.6%), 3.5% (2.4%), 10.2% (4.4%) and 11.7% (5.0%), respectively. Patients with CSF blasts had a higher rate of initial bad risk features. Multivariate analysis indicated that presence of blasts in the CSF had no prognostic value: (i) for EFS and OS; (ii) for isolated and isolated or combined CNS relapse; WBC count<25 × 10(9)/L and Medac E-coli asparaginase treatment were each related to a lower CNS relapse risk.

CONCLUSIONS

The presence of initial CNS involvement has no prognostic significance in EORTC 58881. Intensification of CNS-directed chemotherapy, without CNS radiation, is an effective treatment of initial meningeal leukaemic involvement.

Is there a difference in childhood T-cell acute lymphoblastic leukaemia and T-cell lymphoblastic lymphoma?

To distinguish the similarities or differences between T-cell acute lymphoblastic leukaemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL), we retrospectively analyzed the clinical, immunophenotypic, cytogenetic, and molecular characteristics in 37 children diagnosed between December 1990 and December 2003. Comparative Expressed Sequence Hybridisation (CESH) was used to determine gene expressing profile in both diseases. Twenty two patients suffered from T-ALL and 15 patients were diagnosed as T-LBL. Immunophenotyping demonstrated a more immature phenotype in T-ALL and a more mature phenotype in T-LBL. Cytogenetic and molecular genetic aberrations were found in 82% of T-ALL compared with 73% of T-LBL. By CESH gene expression profiling, the investigated cases were segregated into two groups that largely corresponded with T-ALL and T-LBL. The clinical presentation and cytogenetic characteristics are largely similar for T-ALL and T-LBL supporting the concept that both represent a spectrum of one single disease. The differences that were found between both neoplasms, in particular in their phenotype and in their expression profile may suggest that most T-ALL derive from a T-cell progenitor of the bone marrow, while thymocytes represent the normal counterpart of T-LBL.

Risk-adjusted therapy of acute lymphoblastic leukemia can decrease treatment burden and improve survival: treatment results of 2169 unselected pediatric and adolescent patients enrolled in the trial ALL-BFM 95

The trial ALL-BFM 95 for treatment of childhood acute lymphoblastic leukemia was designed to reduce acute and long-term toxicity in selected patient groups with favorable prognosis and to improve outcome in poor-risk groups by treatment intensification. These aims were pursued through a stratification strategy using white blood cell count, age, immunophenotype, treatment response, and unfavorable genetic aberrations providing an excellent discrimination of risk groups. Estimated 6-year event-free survival (6y-pEFS) for all 2169 patients was 79.6% (+/- 0.9%). The large standard-risk (SR) group (35% of patients) achieved an excellent 6y-EFS of 89.5% (+/- 1.1%) despite significant reduction of anthracyclines. In the medium-risk (MR) group (53% of patients), 6y-pEFS was 79.7% (+/- 1.2%); no improvement was accomplished by the randomized use of additional intermediate-dose cytarabine after consolidation. Omission of preventive cranial irradiation in non-T-ALL MR patients was possible without significant reduction of EFS, although the incidence of central nervous system relapses increased. In the high-risk (HR) group (12% of patients), intensification of consolidation/reinduction treatment led to considerable improvement over the previous ALL-BFM trials yielding a 6y-pEFS of 49.2% (+/- 3.2%). Compared without previous trial ALL-BFM 90, consistently favorable results in non-HR patients were achieved with significant treatment reduction in the majority of these patients.

Overt testicular disease (OTD) at diagnosis is not associated with a poor prognosis in childhood acute lymphoblastic leukemia: results of the EORTC CLG Study 58881

To assess the prognosis of overt testicular disease (OTD) at diagnosis of acute lymphoblastic leukemia (ALL), we analyzed the outcome of 1,165 boys enrolled in EORTC trial 58881. Thirteen (1.1%) boys had OTD associated with bad prognostic features. Patients with and without OTD did not differ in event-free survival (EFS) (P=0.30) or overall survival (OS) (P=0.54), even after adjustment for the three most important independent factors (NCI risk group, presence of very high risk features, type of asparaginase used). OTD was not an independent prognostic factor. These results may be due to the use of risk-adjusted intensive chemotherapy comprising high-dose methotrexate.

Diagnosis and Treatment of Childhood Non-Hodgkin Lymphoma

Major advances have been made in the treatment of childhood non-Hodgkin lymphoma (NHL). The recognition that different NHL subtypes require different treatment strategies was fundamental to developing successful therapy regimens. Currently established therapy groups are lymphoblastic lymphoma (LBL) of precursor B- or T-cell type, mature B-cell neoplasms (B-NHL), and anaplastic large cell lymphoma (ALCL). Accurate diagnostic classification is crucial for allocating patients to appropriate treatment groups. Therapy protocols designed to treat children with acute lymphoblastic leukemia (ALL) have proven highly efficacious for treating children with LBL and are associated with event-free survival (EFS) rates up to 80%. For children with B-NHL, a strategy of rapidly repeated short, dose-intense courses proved more efficacious, with EFS rates up to 90%. In patients with ALCL, comparable results are achieved with either strategy, although this group has the highest relapse rate. The price of these efficacious treatments is considerable toxicity. On the other hand, the chance to survive after relapse is still dismal due to the almost complete lack of established salvage regimen. Thus, refinement of the balance between treatment burden and individual patient risk for failure is a major future task. A variety of new treatment options, some already established for treating adult NHL, await evaluation in childhood NHL.

Diagnosis and Treatment of Childhood Non-Hodgkin Lymphoma

Major advances have been made in the treatment of childhood non-Hodgkin lymphoma (NHL). The recognition that different NHL subtypes require different treatment strategies was fundamental to developing successful therapy regimens. Currently established therapy groups are lymphoblastic lymphoma (LBL) of precursor B- or T-cell type, mature B-cell neoplasms (B-NHL), and anaplastic large cell lymphoma (ALCL). Accurate diagnostic classification is crucial for allocating patients to appropriate treatment groups. Therapy protocols designed to treat children with acute lymphoblastic leukemia (ALL) have proven highly efficacious for treating children with LBL and are associated with event-free survival (EFS) rates up to 80%. For children with B-NHL, a strategy of rapidly repeated short, dose-intense courses proved more efficacious, with EFS rates up to 90%. In patients with ALCL, comparable results are achieved with either strategy, although this group has the highest relapse rate. The price of these efficacious treatments is considerable toxicity. On the other hand, the chance to survive after relapse is still dismal due to the almost complete lack of established salvage regimen. Thus, refinement of the balance between treatment burden and individual patient risk for failure is a major future task. A variety of new treatment options, some already established for treating adult NHL, await evaluation in childhood NHL.

CNS prophylaxis in lymphoma: Who to target and what therapy to use

The purpose of this article is to review the current data on the risk of CNS relapse in patients with lymphoma and the efficacy of CNS directed prophylactic therapy. CNS relapse occurred in 30-50% of those with Burkitt lymphoma and acute lymphoblastic leukaemia/lymphoma prior to the introduction of intensified regimens that include CNS prophylaxis. Most patients with AIDS-related-lymphoma receive a short course of intrathecal prophylaxis but a re-evaluation of type and targeting of CNS prophylaxis is needed. Patients with diffuse large B-cell lymphoma (DLBCL) have a 5% overall risk of CNS relapse but a high risk sub-population can be identified on the basis of raised LDH and >1 extranodal site, testicular or primary breast involvement. CNS prophylaxis for selected patients with DLBCL may be justified by risk but its benefit is not yet proven. Intravenous methotrexate > or = 3 g/m(2) achieves therapeutic levels in CSF and parenchyma and in combination with intrathecal methotrexate would be a reasonable option for prophylaxis.

Allogeneic stem cell transplantation in children with acute lymphoblastic leukemia after isolated central nervous system relapse: our experiences and review of the literature

The prognosis of patients with acute lymphoblastic leukemia (ALL) and central nervous system (CNS) relapse has historically been very poor. Although chemo-radiotherapy has improved outcomes, some patients still have a poor prognosis after CNS relapse. Therefore, allogeneic hematopoietic stem cell transplantation (allo-SCT) has recently become an option for treatment of CNS leukemia; however, information, particularly on the long-term outcome of transplant recipients, is limited. We performed allo-SCT in eight pediatric patients with ALL (n=7) or T-cell type non-Hodgkin's lymphoma (n=1), who had isolated CNS relapse. All patients survived for a median of 70.5 (range, 13-153) months after SCT. Sequelae developed late in some patients: mental retardation (IQ=47) in one patient, severe alopecia in two patients, limited chronic graft-versus-host-disease in three patients, and amenorrhea and/or hypothyroidism in three patients. Except for a pre-school child with post transplant CNS relapse, six out of seven patients show normal school/social performance. Our results clearly indicate a high cure rate of isolated CNS relapse by allo-SCT in pediatric lymphoid malignancies; however, there needs to be further studies to determine which are the appropriate candidates for transplantation and what is the best transplant regimen to achieve high cure rate and maintain good quality of life.

Childhood and adolescent non-Hodgkin lymphoma: new insights in biology and critical challenges for the future

Pediatric non-Hodgkin lymphoma (NHL) is a common and fascinating group of diseases with distinctive underlying genetic events that characterize the major histologic subtypes: diffuse large B-cell lymphoma, Burkitt lymphoma, anaplastic large cell lymphoma and lymphoblastic lymphoma. With systematic improvements in therapy over recent decades, the vast majority of children with NHL of all subtypes are now cured. The similarities and differences between adult and childhood presentations of disease, and whether or not some subtypes of NHL and leukemia are the same or different disease entities, are interesting questions that will be addressed with advances in our understanding of the molecular and genetic bases of these diseases. As is the case with other pediatric malignancies, growing emphasis is now being placed on the development of less toxic, targeted therapeutic approaches, and this review highlights some of the biological discoveries that will potentially open these avenues.

Continuing challenges in childhood non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma in children includes a number of different pathological subtypes and, with improved diagnostic techniques and better understanding of the natural history of each type, treatment strategies have become more tumour-specific. Original staging systems are now less useful in determining treatment stratification and there is a need for careful analysis of large cohorts of patients, treated in the same manner, to determine the clinical and biological features that, with current therapies, are of prognostic value. Novel imaging techniques, such as positron emission tomography, and molecular techniques to detect low-level marrow involvement are likely to be incorporated into new risk grouping. These will be used to determine the extent of initial disease and evaluate more accurately the speed and quality of response to chemotherapy. With high cure rates, it becomes particularly important to minimize late effects of therapy and the introduction of monoclonal antibodies in combination with chemotherapy may provide a method for improving outcome in poor risk groups and reducing sequelae by allowing reduction in chemotherapy in good risk patients.

Attention and information processing in survivors of childhood acute lymphoblastic leukemia treated with chemotherapy only

BACKGROUND

Omitting radiotherapy for central nervous system (CNS) prophylaxis has improved the overall quality of life for long-term survivors of childhood acute lymphoblastic leukemia (ALL). However, recent reports suggest minor cognitive impairment in survivors who received chemotherapy only.

PROCEDURE

This study focused on attentional functioning and speed of information processing in 23 children previously treated for ALL according to EORTC 58881 and EORTC 58951 protocol. Patients received intrathecal methotrexate combined with high doses intravenous methotrexate as CNS prophylaxis. Cognitive functioning was assessed with the Amsterdam Neuropsychological Tasks, a computerized attention assessment program. Variables of both speed and accuracy of the patients were compared with those obtained from 23 age- and sex-matched control children.

RESULTS

Patients were equal to control children concerning baseline speed, sustained attention, response inhibition, and response organization. However, they were significantly slower than controls in three tasks: encoding, memory search letters, and focused attention 4-letters. Interactions with the difficulty of the task were found. There were no differences in number or type of errors between groups on all tasks.

CONCLUSIONS

ALL survivors treated with chemotherapy have specific information processing difficulties. They process information slower than control children, especially when more information has to be processed or when attention has to be focused precisely. In spite of being slower, patients are equally accurate compared to control children.

Value of intravenous 6-mercaptopurine during continuation treatment in childhood acute lymphoblastic leukemia and non-Hodgkin's lymphoma: final results of a randomized phase III trial (58881) of the EORTC CLG

Between November 1990 and November 1996, EORTC Children Leukemia Group conducted a randomized trial in de novo acute lymphoblastic leukemia and lymphoblastic non-Hodgkin's lymphoma patients using a Berlin-Frankfurt-Munster protocol to evaluate the monthly addition of intravenous 6-mercaptopurine (i.v. 6-MP) (1 g/m(2)) to conventional continuation therapy comprising per oral MTX weekly and 6-MP daily. Only during the first 18 months of the randomization period, 6-MP p.o. was interrupted for 1 week after each i.v. 6-MP. A total of 877 patients was randomized to either no i.v. 6-MP (Arm A) or additional i.v. 6-MP (Arm B). A total of 217 relapses (91 in Group A vs 128 in Group B) and 13 deaths in CR (5 vs 8) were reported; a total of 134 patients (55 vs 79) died. The median follow-up was 7.6 years. At 8 years, the disease-free survival rate was lower (P=0.005) in Arm B (69.1% (s.e.=2.2%)) than in Arm A (77.9% (s.e.=2.0%)), and the hazard ratio was 1.45 (95% CI 1.12-1.89). In conclusion, as delivered in this study, i.v. 6-MP was detrimental to event-free survival.

CNS-directed therapy in young children with T-lineage acute lymphoblastic leukemia: High-dose methotrexate versus cranial irradiation

BACKGROUND

Prophylactic use of cranial radiation therapy (CRT) in young children with acute lymphoblastic leukemia (ALL) is associated with significant long-term morbidity. Therefore, current treatment protocols for pediatric B-precursor ALL have abandoned prophylactic CRT in favor of intrathecal chemotherapy, combined with either high-dose methotrexate infusions (HD-MTX) or intensive systemic chemotherapy. In contrast, prophylactic CRT continues to be used in children with T-lineage ALL (T-ALL), who historically have had an inferior prognosis. We conducted a retrospective cohort study to determine the effect on survival of substituting HD-MTX for CRT in young children with T-ALL, a group that faces a high risk of long-term sequelae from CRT.

PROCEDURE

Twenty-six children, diagnosed with T-ALL between the ages of 1 and 5 years, were treated on the same high-risk leukemia protocol. Central nervous system (CNS) directed therapy consisted of either CRT (1,800 cGy) or HD-MTX (three doses of 8 g/m2), depending on the treatment era in which patients were diagnosed.

RESULTS

Of the 24 patients who entered remission, 12 received CRT and 12 received HD-MTX. Five-year event-free survival (EFS) (+/-SE) was 92 +/- 8% in the HD-MTX group versus 75 +/- 13% in the CRT group (P=0.23). Five-year overall survival (OS) was 100% in the HD-MTX group versus 75 +/- 13% in the CRT group (P=0.07). There were no CNS recurrences in the HD-MTX group. One patient treated with CRT developed a brain tumor.

CONCLUSIONS

The use of HD-MTX instead of CRT as CNS-directed therapy in very young children with T-ALL does not compromise survival, while avoiding the adverse long-term effects of cranial irradiation.

Schedule-dependent synergism and antagonism between methotrexate and cytarabine against human leukemia cell lines in vitro

Methotrexate (MTX) and cytarabine have been widely used for the treatment of acute leukemias and lymphomas for over 30 years. However, the optimal schedule of this combination is yet to be determined and a variety of schedules of the combination has been used. We studied the cytotoxic effects of MTX and cytarabine in combination against human leukemia cell lines at various schedules in vitro. The effects of the combinations at the concentration of drug that produced 80% cell growth inhibition (IC(80)) were analyzed using the isobologram method of Steel and Peckham. Simultaneous exposure to MTX and cytarabine for 3 days produced antagonistic effects in human T cell leukemia, MOLT-3 and CCRF-CEM, B cell leukemia, BALL-1, Burkitt's lymphoma, Daudi, promyelocytic leukemia, HL-60 and Philadelphia chromosome-positive leukemia, K-562 cells. Simultaneous exposure to MTX and cytarabine for 24 h produced antagonistic effects, sequential exposure to MTX for 24 h followed by cytarabine for 24 h produced synergistic effects, and the reverse sequence produced additive effects in both CCRF-CEM and HL-60 cells. Sequential exposure to MTX for 24 h followed by cytarabine for 3 days also produced synergistic effects in MOLT-3 cells. Cell cycle analysis supported these observations. Our findings suggest that the simultaneous administration of MTX and cytarabine is not appropriate and the sequential administration of MTX followed by cytarabine may be the optimal schedule of this combination.

The Children Leukemia Group: 30 years of research and achievements

The EORTC Children Leukemia Group (CLG) is part of the offspring of the EORTC Hemopathies Working Party which in 1978 split into a paediatric and to an 'adult' branch. At that time, the Berlin-Frankfurt-Munster (BFM) designed by H. Riehm for acute lymphoblastic leukaemia (ALL) appeared much more efficacious than all others and the CLG decided to adapt that treatment strategy for its own clinical trials. The main results of these may be summarised as follows:for standard risk patients, the deletion of cyclophosphamide from consolidation and reconsolidation courses does not jeopardise the patient's outcomefor medium- and high-risk patients receiving high-dose methotrexate (MTX), cranial radiotherapy is superfluouswith the dose scheduling of the BFM regimen, E-Coli L-Asparaginase is more efficacious than Erwinia L-Asparaginasethe addition of monthly intravenous (i.v.) 6-mercaptopurine to conventional maintenance chemotherapy is detrimentalthe assessment by quantitative polymerase chain reaction (PCR) of minimal residual disease at completion of induction is feasible in a cooperative setting and can be used as a powerful and independent prognostic factor. The CLG also conducted clinical studies of acute myeloblastic leukaemia. Since 1989, lymphoblastic non-Hodgkin's lymphomas have been treated within the ALL trials. The CLG collaborates with other Groups within the I-BFM Study Group and participants in the meta-analytic studies conducted by the Oxford team by the Oxford Children ALL Collaborative Group.