Prolonged second remissions in childhood acute lymphocytic leukemia: a report from the Childrens Cancer Study Group

Bone Marrow Transplantation Versus Prolonged Intensive Chemotherapy for Children With Acute Lymphoblastic Leukemia and an Initial Bone Marrow Relapse Within 12 Months of the Completion of Primary Therapy: Children's Oncology Group Study CCG-1941

Purpose

To compare conventional sibling bone marrow transplantation (CBMT), BMT with alternative donor (ABMT), and chemotherapy (CT) for children with acute lymphoblastic leukemia (ALL) and an early first marrow relapse.

Patients and Methods

After informed consent, 214 patients with ALL and early marrow relapse began multiagent induction therapy. One hundred sixty-three patients with fewer than 25% marrow blasts and count recovery at the end of induction (second remission [CR2]) were allocated by donor availability. Fifty patients with sibling donors were allocated to CBMT. Seventy-two patients were randomly allocated between ABMT and CT while 41 patients refused allocation.

Results

Overall, 3-year event free survival from entry is 19% ± 3%. Thirty-two of 50 CBMT patients (64%) and 19 of 37 ABMT patients (51%) underwent transplantation in CR2 with 3-year disease-free survival of 42% ± 7% and 29% ± 7%. The 3-year DFS is 29% ± 7%, 21% ± 7%, and 27% ± 8% for patients allocated to CBMT, ABMT, and CT, respectively. Contrary to protocol, 12 of 35 patients allocated to CT underwent BMT in CR2. Of these, five patients died after BMT and 5 patients relapsed.

Conclusion

More than one half of patients died, failed reinduction, or relapsed again before 3 months after CR2 (median time to BMT). Intent-to-treat pair-wise comparison of ABMT with CT, CT with CBMT, and CBMT with ABMT yields hazards of 1.2, 1.1, 0.8 with P values of .56, .80, and .36, respectively. Outcomes remain similar and poor for children with ALL and early marrow relapse. BMT is not a complete answer to the challenge of ALL and early marrow relapse.

Childhood acute lymphoblastic leukaemia and relapse

Acute lymphoblastic leukaemia (ALL) is the most common childhood cancer. Treatment has improved but relapsed ALL remains more common than new cases of many 'common' paediatric malignancies. We have salvage regimens with substantial complete remission (CR) rates and increasing access to haematopoietic stem cell transplantation, but most patients who relapse die. We need better therapies. Insights into pharmacology may guide more effective use of existing agents. Novel agents with activity against resistant lymphoblasts offer an appealing strategy. However, most candidate agents fail, despite enthusiastic investigators, intriguing mechanisms of action and 'compelling' preclinical data. A number of existing combinations provide a 40% complete response rate in second or third relapse. Yet survival in third remission is <10%. Novel agents must, most likely, be integrated into multiagent combinations that provide a higher CR rate or better quality CR's than our conventional combinations in order to contribute substantially to cure. The march from bench to bedside requires careful consideration of the intermediate steps.

Allogeneic bone marrow transplantation versus chemotherapy for the treatment of childhood acute lymphoblastic leukemia in second remission: a single-institution study

PURPOSE

A retrospective analysis of the treatment of childhood acute lymphoblastic leukemia (ALL) in second remission (CR2) was undertaken at our institution to compare the outcome and prognostic factors of patients treated with chemotherapy or allogeneic bone marrow transplantation (BMT).

PATIENTS AND METHODS

Seventy-five children who suffered a medullary relapse and achieved a second remission were treated with either an unmodified allogeneic HLA-matched sibling BMT after hyperfractionated total body irradiation (TBI) and cyclophosphamide (n = 38) or chemotherapy according to institutional chemotherapy protocols (n = 37). To avoid the bias of survival from the attainment of second remission in favor of BMT, the final comparative statistical analysis used the landmark approach and comprised 37 and 29 patients from the BMT and chemotherapy groups, respectively

RESULTS

The disease-free survival (DFS) rate was 62% and 26% at 5 years, respectively, for the BMT and the chemotherapy groups (P = .03), with relapse rates of 19% and 67%, respectively, for these two groups (P = .01). There was an overall advantage for the BMT therapeutic approach, as compared with chemotherapy, for patients with ALL in CR2 (1) for patients with a WBC count (at diagnosis) of 20 x 10(9)/L or higher (DFS, 40% v 0%) and those with a WBC count of less than 20 x 10(9)/L (DFS, 73% v35%), (2) for patients whose duration of CR1 was less than 24 months (DFS 48% v 9%) and for patients whose duration of CR1 was 24 months or longer (DFS, 81% v 37%) and (3) for patients who were initially treated with intensive regimens incorporating more than five chemotherapy agents (DFS, 57% v 20%) and for patients treated with five agents or fewer (DFS, 72% v 32%).

CONCLUSION

In our single-institution series, unmodified HLA-matched allogeneic sibling transplants using hyperfractionated TBI and cyclophosphamide for patients with ALL in CR2 have resulted in superior outcome with a significantly improved probability of DFS and a lower relapse rate, as compared with those for patients treated with chemotherapy, regardless of the duration of first remission, the disease characteristics at diagnosis, or the intensity of prior treatment during first remission.

An open-label, multicenter study of polyethylene glycol-L-asparaginase for the treatment of acute lymphoblastic leukemia

BACKGROUND

L-asparaginase has been a mainstay of therapy along with vincristine and prednisone in the treatment of acute lymphoblastic leukemia (ALL) in children for almost 30 years. Because L-asparaginase is a foreign protein, the potential exists for severe, dose-limiting hypersensitivity reactions. To reduce this toxicity, L-asparaginase has been linked with polyethylene glycol (PEG).

METHODS

Patients with ALL in relapse were entered in a Phase II, open-label clinical trial (ASP-201A) to evaluate the toxicity and efficacy of PEG-L-asparaginase. PEG-L-asparaginase has demonstrated potential low immunogenicity and a prolonged plasma half-life relative to native enzyme. PEG-L-asparaginase (2000 IU/m2 every 2 weeks) was used as single-agent induction therapy during an initial 14-day investigational window. Thereafter, the regimen consisted of PEG-L-asparaginase, vincristine, and prednisone. Patients also were allowed to receive doxorubicin and intrathecal chemotherapy beginning on day 14. All patients had been treated previously with one or more courses of native L-asparaginase; one of these patients was hypersensitive to L-asparaginase at enrollment.

RESULTS

During the 14-day investigational window with PEG-L-asparaginase monotherapy, 22% of patients examined achieved a complete or partial remission. By completion of the 35-day induction period, 78% (or 14 of 18) of evaluated patients achieved complete or partial remission. Anaphylaxis did not occur during treatment. Mild urticaria and mild local allergic reactions occurred in five patients but did not cause discontinuation of treatment. The incidence of hyperglycemia and pancreatitis was less than expected from historic data published for previous studies with native L-asparaginase.

CONCLUSIONS

As administered in this study, PEG-L-asparaginase can be given safely with a spectrum of toxicity similar to that of native L-asparaginase. Single-agent activity was documented in patients with ALL in bone marrow relapse.

Bone marrow transplants from HLA-identical siblings as compared with chemotherapy for children with acute lymphoblastic leukemia in a second remission

BACKGROUND

It is unclear how best to treat children with acute lymphoblastic leukemia who are in a second remission after a bone marrow relapse. For those with HLA-identical siblings, the question of whether to perform a bone marrow transplantation or to continue chemotherapy has not been answered.

METHODS

We compared the results of treatment with marrow transplants from HLA-identical siblings in 376 children, as reported to the International Bone Marrow Transplant Registry, with the results of chemotherapy in 540 children treated by the Pediatric Oncology Group. A preliminary analysis identified variables associated with treatment failure in both groups. We selected cohorts by matching these variables. A possible bias associated with differences in the interval between remission and treatment was controlled for by choosing matched pairs in which the duration of the second remission in the chemotherapy recipient was at least as long as the time between the second remission and transplantation in the transplant recipient. A total of 255 matched pairs were studied.

RESULTS

The mean (+/- SE) probability of a relapse at five years was significantly lower among the transplant recipients than among the chemotherapy recipients (45 +/- 4 percent vs. 80 +/- 3 percent, P < 0.001). At five years the probability of leukemia-free survival was higher after transplantation than after chemotherapy (40 +/- 3 percent vs. 17 +/- 3 percent, P < 0.001). The relative benefit of transplantation as compared with chemotherapy was similar in children with prognostic factors indicating a high or low risk of relapse (the duration of the first remission, age, leukocyte count at the time of the diagnosis, and phenotype of the leukemic cells).

CONCLUSIONS

For children with acute lymphoblastic leukemia in a second remission, bone marrow transplants from HLA-identical siblings result in fewer relapses and longer leukemia-free survival than does chemotherapy.

Chemotherapy versus bone marrow transplantation in childhood acute lymphoblastic leukaemia. BFM Study Group

Twenty-five years ago over 90% of children with acute lymphoblastic leukaemia (ALL) died of this disease. Dramatic improvement has been achieved since then by employing risk-adapted, aggressive polychemotherapy protocols. More than 90% of children with ALL treated according to, for example BFM-protocols, have nowadays cure rates in the range of 70%-80%. However, 10% of patients do not initially respond adequately to standard induction chemotherapy. They are characterized by distinct chromosomal abnormalities such as translocation (9; 22) or combinations of early treatment failure and other risk factors as cytogenetic abnormalities, lineage-specific surface markers or tumour load at diagnosis. In this group of patients in first complete remission and certainly in the vast majority of relapsed patients, allogeneic bone marrow transplantation (BMT) has evolved as an alternative approach allowing further intensification of myeloablation and the introduction of an additional antileukaemic alloreactivity. Nevertheless, the decision for a marrow transplant in children has to be made very carefully because of a significant increase in treatment related mortality and BMT-specific risks like acute and chronic graft-versus-host disease with a critical iatrogenic chronic morbidity. This is even more evident, if mismatched or unrelated transplants are being considered. The indications for one or the other treatment modality according to the current BFM strategy are discussed.

Association of delivered drug dose and outcome for children with acute lymphoblastic leukemia and unfavorable presenting features

Dose and dose intensity are believed critical for attaining a maximal therapeutic effect in drug-responsive tumor systems. Childhood acute lymphoblastic leukemia may be an example of such a drug-responsive system as it is cured with current chemotherapy in a majority of cases. Between August 1981 and May 1983, the Childrens Cancer Study Group enrolled 209 children with ALL and unfavorable presenting features in CCG-193P, a trial based on the Berlin Frankfurt Munster 76/79 regimen. The cumulative delivered dose of each medication was recorded prospectively. Patients who completed the intensive portion of therapy in continuous complete remission were ranked by the percentage of protocol required drug delivered from the initiation of therapy to that date. No association was found between delivery of any single drug and subsequent disease-free survival. However, when patients were ranked by the sum of the percentages of protocol vincristine, l-asparaginase, and anthracycline delivered, children in the approximate middle and lower tertiles were 3 and 5 times more likely to have had a subsequent relapse than were those in the upper tertile (P = 0.025, test for trend). Delivery of the full protocol prescribed dose of these agents may have been critical, but corroboration is certainly needed. Only prospective trials can determine if children with acute lymphoblastic leukemia and unfavorable presenting features might benefit from greater use of vincristine, l-asparaginase, and/or anthracycline.

Remission induction and continuation therapy in children with their first relapse of acute lymphoid leukemia. A Pediatric Oncology Group study

Between January 1979 and April 1983, 113 children undergoing their first relapse of acute lymphoid leukemia (ALL) at any site were registered in Pediatric Oncology Group study 7834; 98 were eligible and evaluable. In addition to radiotherapy administered to sites of local relapse, induction consisted of vincristine, doxorubicin, and prednisone (VAP) chemotherapy. Continuation therapy consisted of triple-drug intrathecal therapy and regimens of 6-thioguanine and cytarabine alternating with vincristine, prednisone, cyclophosphamide, and cytarabine. Randomization in continuation was between VAP pulses or no pulse, regardless of the site of relapse. This report provides long-term follow-up of these patients. Thirty-two of 39 children with bone marrow involvement achieved a complete response (CR). Only one of these is alive in an unmaintained remission, a child who did not have an initial CR. Thirty-four of 36 evaluable children with central nervous system involvement as the site of relapse achieved CR. Of these ten are alive; eight are in continuing CR. Nineteen of 20 boys with testicular relapse achieved CR. Of these, 14 are still alive and not receiving therapy, although only one half received treatment in compliance with the protocol described. These results illustrate the possibility of cure of patients who have relapsed with ALL when it is (1) confined to a meningeal or gonadal site and (2) treated vigorously with radiotherapy and a new regimen of systemic chemotherapy. The results reconfirm the need to prevent an initial relapse at any site.

Multiagent chemotherapy in relapsed acute lymphoblastic leukemia in children

Twenty-seven evaluable children with early first bone marrow relapse of acute lymphoblastic leukemia were treated with an intensive induction/consolidation and ongoing maintenance therapy. Induction therapy consisted of a 35-day course of daunomycin, vincristine, and prednisone, immediately followed by teniposide, cytosine arabinoside (Ara-C), and L-asparaginase. Intrathecal methotrexate, hydrocortisone, and Ara-C were given through the induction/consolidation phase. Twenty-three of 27 patients achieved remission by the end of induction/consolidation. Maintenance with the same drugs in a modified dosage schedule continued for approximately 2 years. A small subgroup of patients who were M3 at day 35 but M1 at day 56 (end of induction/consolidation) and had a cumulative event-free survival (EFS) of only 0.40 at 6 months, all had relapsed by 15 months. However, the EFS for M1 patients by day 35 and maintained on chemotherapy was 0.64 at 12 months and 0.32 at 30, 36, and 48 months, respectively. Although good reinduction and remission duration rates at 12 to 24 months were achieved and an apparent plateau in survival occurs at 30 months, fall-off in survival would not be unexpected with probably less than 20% alive after 5 years.

Bone marrow transplantation for childhood acute lymphoblastic leukaemia after marrow relapse

Children with acute lymphoblastic leukaemia in whom relapse in bone marrow occurs have a poor outlook when treated with chemotherapy alone. Twenty-seven patients with childhood acute lymphoblastic leukaemia were treated for marrow relapse with high-dose chemotherapy with or without total body irradiation followed by bone marrow transplantation (BMT). Twenty patients received allogeneic marrow from partially or completely matched histocompatible donors. In this group, nine patients (45%) were free of disease with a median follow-up of 57 months (range, 22 to 126 months) after transplantation, four (20%) died from interstitial pneumonitis and seven (35%) died after a further relapse. Seven patients received autologous marrow collected while they were in remission. In this group, one patient died from infection and six died after a further relapse. We conclude that allogeneic BMT is more effective than autologous transplantation and results in long-term disease-free survival in a significant number of patients. New methods are needed to eradicate residual disease in the patient and to purge marrow ex vivo.

Non-randomised study comparing toxicity of Escherichia coli and Erwinia asparaginase in children with leukaemia

Seven hundred fifty-eight unselected children entered into the United Kingdom Medical Research Council acute lymphoblastic leukaemia UKALL VIII Study and Trial were studied for differences in early treatment-related toxicity according to the type of intramuscular L-asparaginase received. Two hundred seventy-five received a product obtained from Escherichia coli and 483 the enzyme from Erwinia chrysanthemi. The E. coli patients had a significantly higher incidence of neurotoxicity, pancreatitis, and life-threatening sepsis (4%, 2%, and 20%, respectively) when compared with the Erwinia group (2%, 0%, and 18%). Severe hypersensitivity was seen in one patient from both groups and the incidence of glucose intolerance was not significantly different. These findings indicate that E. coli asparaginase may be more toxic. With a minimum follow up of 4 1/2 years there is no evidence that either product has made a significantly different contribution to disease-free survival.

Bone marrow relapse occurring as first relapse in children with acute lymphoblastic leukemia

In a retrospective review which covered the whole Dutch childhood population of approximately 3 million children we studied the prognosis in 164 children with acute lymphoblastic leukemia (ALL) who were initially treated between 1973 and 1983, and who had an isolated bone marrow relapse occurring as first relapse. Until their first relapse, the patients were initially treated according to standard protocols, while treatment for relapse was heterogeneous, and not intensive. Second complete remission (CR) was attained by 78% of the patients. The median duration of second CR was 9 months, the median survival 13 months. Multivariate analysis showed that the duration of the first CR was the most significant variable with regard to prognosis. None of the patients who developed their bone marrow relapse during initial treatment, i.e., within 24 months from diagnosis, survived. Among the 73 patients who relapsed after cessation of the initial treatment there were 19 long-term disease-free survivors, 14 of whom had not developed subsequent relapses after 48(+)-125 + months. From this study we conclude that treatment in children with first bone marrow relapse has to be intensified.

Reinduction therapy for advanced or refractory acute lymphoblastic leukemia of childhood

Thirty-four children after multiple relapse or with refractory acute lymphoblastic leukemia were treated with two novel combinations of high-dose cytosine arabinoside, methotrexate, asparaginase, vincristine, and prednisone. The first combination was given to 19 patients. Oncolytic response and marrow hypoplasia was achieved in all. There were four early infectious deaths. Thirteen of the remaining 15 (87%) in whom the response to therapy could be evaluated achieved complete remission. Two achieved good partial remissions. The median duration of complete remission and survival on study was 8 and 10 months, respectively. The four proven and three suspected fungal infections seen in the initial 19 patients was the major toxicity observed. The therapy was modified in the last 15 patients to retain efficacy while reducing the period of neutropenia from a median of 28 to 22 days. No deep-seated fungal infections were seen in these patients. Twelve (80%) achieved a complete remission. Three had an oncolytic response without achieving remission. Eighty-three percent of the 30 evaluable patients, or 74% of all patients entered on study, achieved remission. It is anticipated that the therapy described here will not only achieve another remission in the majority of patients with advanced ALL but that the patients will be able to proceed to alternate therapies with potentially more durable benefit.

Biologic and cytogenetic characteristics of leukemia in infants

Clinical features, leukemic cell characterization, chromosomal findings, and treatment outcome were analyzed in a retrospective study of 30 cases with acute leukemia of infancy, 24 infants with acute lymphoblastic leukemia (ALL), and six cases with acute nonlymphoblastic leukemia (ANLL). Extensive bulky disease with organomegaly, central nervous system (CNS), and skin involvement were prominent features at diagnosis with a higher frequency in ANLL as compared to ALL. Four of six ANLL patients were classified as monocytic or myelomonocytic. In the ALL group nine of 24 (36%) were non-L1 morphology and six of 17 (33%) were common ALL antigen (CALLA) negative, the majority of them (five of six) were included in the non-L1 group. Immunophenotyping revealed four cases with early B-cell (three patients: Ia+B4+, and one patient: Ia+) and two cases with T-cell. Mixed lineage leukemia was found in five infants. Heavy chain immunoglobulin gene rearrangement was present in six cases tested, two CALLA+, two with Ia+B4+, and two were undifferentiated mixed lineage leukemia. Chromosomal aberrations were detected in ten of 18 patients, mostly in ANLL and CALLA negative ALL. Translocations were detected in six patients, involving 4q21-23 and 11q23 in three and two cases, respectively. The probability of five-year DFS were 27% for the whole group. The worst prognosis was observed in infants younger than 6 months of age, in whom the leukemia cell characteristics was compatible with stem cell: ANLL, very early pre-B, or undifferentiated mixed type. The chromosomal aberrations found in all cases included translocation with the seemingly nonrandom breakpoints at 4q21 and 11q23, and breakpoints that corresponded to known fragile sites. This finding may be suggestive of an underlying genetic predisposition associated with the poor prognosis of leukemia of infancy.

Acute lymphoblastic leukemia in childhood

This article reviews the current biologic understanding of acute lymphoblastic leukemia and describes current approaches to treatment. It discusses the areas likely to be the focus of future research for this disease, including therapy for high-risk patients, understanding the reasons for treatment failure, and identification of new antileukemic agents.

Childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia accounts for 80% of leukemia in children. The exact cause is unknown, but some genetic, immunologic, viral, and environmental factors have been implicated. Symptoms at the time of diagnosis frequently include fever, bleeding, fatigue, and irritability. Initial white blood cell count and patient age at diagnosis are the most reliable indicators of prognosis. Acute lymphoblastic leukemia is a heterogenous disease. Lymphoblast morphology, immunologic markers, enzyme abnormalities, cytogenetic findings, and staining characteristics in conjunction with clinical characteristics allow classification into risk groups. Appropriate therapy for each risk group is based on these parameters. Combination chemotherapy administered alone or with additional chemotherapy or radiotherapy to sanctuary sites is the principal modality for treatment of ALL. Optimal therapy for relapse has not yet been determined, but for patients with appropriate donors, allogeneic bone marrow transplant is promising. Common complications of chemotherapy include tumor lysis syndrome, myelosuppression, and other problems such as gastrointestinal toxicity, neurotoxicity and cardiac toxicity. Significant late effects of chemotherapy include neurological impairment ranging from learning problems to leukoencephalopathy and a possible increased risk of second malignancy. Complete remission is achieved in 95% of children with acute lymphoblastic leukemia, and more than 55% will continue to be in complete remission at five years. Optimal CNS prophylaxis, effective treatment of relapse, and adjustment of therapy to minimize acute and late adverse effects are a continuing challenge. With improved understanding of biologic factors, and development of more specific therapy for each subgroup, children with acute lymphoblastic leukemia should enjoy a better long term outcome.

Monoclonal antibody-ricin conjugate cytotoxic to cells expressing the common acute lymphoblastic leukemia antigen (CALLA)

The monoclonal antibody PHM-6, which is specific for the common acute lymphoblastic leukemia antigen (CALLA), was conjugated to the plant toxin ricin. Binding of the PHM-6-ricin conjugate to cells via the ricin molecule was blocked by the presence of 100 mM lactose. The IC50 (concentration resulting in 50% inhibition) of the PHM-6-ricin conjugate for the CALLA-positive KM-3 cell line was 280-fold greater than for bone marrow stem cells, indicating the potential of this conjugate for immunological purging of autologous remission marrow.

Which treatment for childhood acute lymphoblastic leukaemia in second remission?

The best therapy for children with acute lymphoblastic leukaemia (ALL) who have an initial bone marrow relapse and subsequently achieve second remission is controversial. Some findings suggest that bone marrow transplantation (BMT) is better than chemotherapy whereas others do not. An analysis of 871 children treated by BMT or chemotherapy showed that outcome was correlated with risk factors at diagnosis and with length of first remission. BMT seemed superior in patients who relapsed within 18 months of first remission while on maintenance chemotherapy. BMT was not demonstrably superior in patients who relapsed more than 18 months after first remission. The choice of treatment in childhood ALL must be based on prognostic variables at diagnosis and on the circumstances of the relapse.

Aggressive combination chemotherapy of bone marrow relapse in childhood acute lymphoblastic leukemia containing aclacinomycin-A: a multicentric trial

An intensive 7-day combination chemotherapy protocol was designed to reinduce children with early bone marrow relapse of acute lymphoblastic leukemia (less than 6 months after the end of or during preceding treatment). This aggressive approach seemed to be justified for a group of patients who were at the highest risk for ultimate treatment failure. In all, 38 children were enrolled for study. The ratio of male (median age, 10 years) to female (median age, 13 years) subjects was 27:11. Thirty patients were treated for their first relapse and eight for their second or subsequent relapse. Isolated bone marrow involvement was present in 24 cases. All patients had received heavy pretreatment including anthracyclines with cumulative doses of between 120 and 240 mg/m2. 22 of these patients, achieved complete remission, ten did not respond to therapy, and six died from the toxicity of the protocol. Cardiac failure was the cause of death in one child (after additional radiotherapy for a mediastinal mass). No further clinical manifestation of cardiomyopathy could be observed. The other five patients died from hemorrhages or infectious complications. The main side effects were fever, gastrointestinal problems, stomatitis, and severe bone marrow aplasia lasting for about 2 weeks with nadirs of platelets and white blood count around days 10-14. The remission rate of 60% was acceptable, though not satisfactory. Only four children survived disease-free for 13+, 14+, 20+, and 22+ months after diagnosis of relapse.

Leukemia of early infancy. Early B-cell lineage associated with t(4:11)

A case of infantile acute leukemia associated with translocation t(4:11)(q21:q23) is reported. This leukemia has a very poor prognosis, and this patient survived for only 9 months. The blast cell morphology was L1/L2 according to the FAB classification and showed a lymphoid appearance on transmission electron microscopy. The histochemical stains showed a pattern of periodic acid-Schiff positivity and variable alpha-naphtyl acetate staining. The cells were TdT-positive and surface-marker phenotyping was positive for Ia-like and B4 antigens but negative for CALLA, T-cell markers, myelocyte and monocyte markers. The leukemic cells represent a frozen state of a very early precursor, corresponding to the earliest recognizable stage of the B-cell lineage. This observation may contribute to the controversion regarding the cell origin of this unique leukemia associated with t(4:11), lymphatic versus null cell, early myeloid, or mixed, and points to the possibility of a very early B-cell lineage leukemia.

Four-agent induction and intensive asparaginase therapy for treatment of childhood acute lymphoblastic leukemia

We prospectively assigned 289 consecutive children with acute lymphoblastic leukemia to receive one of two treatment programs on the basis of the presence or absence of certain risk factors at the time of diagnosis. Patients at high risk (62 percent of the total) had one or more of the following risk factors: age below two or above nine years, a white-cell count of 20,000 per cubic millimeter or more, the presence of T-cell immunologic markers, radiologic evidence of a mediastinal mass, and involvement of the central nervous system. Patients in both the standard-risk and high-risk groups were treated for two years, receiving intensive remission-induction therapy, central nervous system prophylaxis, weekly administration of high-dose asparaginase, and multiple-drug continuation therapy (which in the high-risk group included doxorubicin and a larger dose of prednisone). At a median follow-up of 35 months, the mean (+/- SE) event-free survival rates at four years among the patients in the standard-risk and high-risk groups were 86 +/- 4 percent and 71 +/- 4 percent, respectively (P = 0.003), for a total event-free survival of 77 +/- 3 percent. Within the high-risk group, the white-cell count at diagnosis and the sex of the patient were not significant prognostic indicators, but age below 12 months at diagnosis was associated with a very poor outcome. As compared with previous methods, this treatment program using four-drug induction and intensive asparaginase therapy has resulted in improved event-free survival in children with acute lymphoblastic leukemia.

Detection of residual acute lymphoblastic leukemia cells in cultures of bone marrow obtained during remission

We used a semisolid culture assay to quantitate leukemia cells in the bone marrow of patients with childhood acute lymphoblastic leukemia (ALL). In bone marrow cultures from 40 patients with newly diagnosed disease, the colonies that developed in vitro consisted of lymphoblasts with the same surface markers and abnormal karyotype as the original diagnostic marrow specimens. We also studied marrow cultures from 13 patients in chemotherapy-induced remission; 6 of these, including 1 obtained from a patient during successful engraftment after marrow transplantation, also yielded lymphoblast colonies in culture, with the same immunologic phenotype or abnormal karyotype as the original leukemic marrow. Four of these patients, including the one who underwent marrow transplantation, relapsed within 2 to 30 months of the abnormal cultures; the other two are still in remission, one of them 30 months after diagnosis. Bone marrow cultures from eight normal controls and from the other seven patients in remission did not yield lymphoblast colonies; all seven of the latter are still in remission. This assay appears to allow detection of small numbers of residual leukemic cells. We conclude that the technique will be valuable in monitoring the efficacy of chemotherapy and allogeneic bone marrow transplantation in acute lymphoblastic leukemia, as well as in evaluating the quality of purged marrow for autologous marrow transplantation.

Intensive retreatment of childhood acute lymphoblastic leukemia in first bone marrow relapse. A Pediatric Oncology Group Study

We devised a plan of intensive chemotherapy to address the problem of inadequate results of treatment in children with acute lymphoblastic leukemia in first bone marrow relapse. Immediately after remission was induced with four conventional drugs, a two-week intensification course of teniposide and cytarabine was given to eradicate subclinical leukemia. Patients in remission were then treated for two years with rapid rotation of pairs of drugs that were not cross-resistant and periodic courses of the same agents used to induce remission. A second complete remission was induced in 31 of the 39 patients in whom response to chemotherapy could be assessed. The probability of maintaining bone marrow remission in these patients for one year was 0.38 +/- 0.19 (95 percent confidence interval); the two-year probability was 0.29 +/- 0.17. Seven patients completed the treatment program, five of whom have been in continuous second complete remission 17 to 20 months after the cessation of therapy. Children whose initial bone marrow remission lasted less than 18 months had significantly poorer responses to retreatment than did those with a longer first remission (P = 0.004). Intensive chemotherapy, as described here, may save half of the children with acute lymphoblastic leukemia in whom bone marrow relapse occurs after a relatively long initial remission.

Autologous bone marrow transplantation (ABMT) for acute leukaemia in complete remission: a pilot study of 33 cases

Thirty-three leukaemic patients in CR were treated by high-dose therapy followed by ABMT: 18 of them had acute non-lymphoblastic leukaemia (ANLL) in first remission (CR1) with a mean age of 23.7 years (3-44). All but one of them were conditioned with a polychemotherapy regimen including 6-thioguanine, Ara-C, CCNU, and cyclophosphamide. The marrow cells were purged by chemical means in 16 cases. Five transplant-related deaths were observed: three cardiac failures, one interstitial pneumonitis and one aspergillus pneumonia. At the time of analysis (October 1984), four patients had relapsed and eight were still in unmaintained CR1 (44+, 46+, 30+, and five between 2.5+ and 8+ months post transplant). Fifteen patients had acute lymphoblastic leukaemia: four were autografted in CR1 and 11 children were grafted in CR2; the conditioning regimen was fractionated total body irradiation followed by cyclophosphamide for all but one patient who was conditioned with BACT (Burkitt leukaemia); the marrow was purged by a chemical agent in 11 patients and by monoclonal antibodies and C' in four: four out of 15 patients relapsed (two grafted in CR1 and two grafted in CR2); 10 patients are still in unmaintained CR: two adults grafted in CR1 (26+; 12+ months) and eight children with a mean follow-up of 13.4 months post graft (2 + -45+ months). The clinical study leads to the following conclusions: in adult patients the marrow should be harvested during CR1 and at the time of minimal residual disease. The quality of previous chemotherapy and conditioning regimen prior to ABMT play a prominent role in the in vivo eradication of the leukaemic cells. The real impact of marrow purging is still unknown and a larger series of homogeneous patients, conditioned with the same protocols and the same transplant timing, is required before any conclusions can be drawn.

Prognosis after relapse in acute lymphoblastic leukemia in childhood

This is a survey of all the 265 relapses occurring in 515 children with ALL diagnosed in Sweden in the years 1973-1980. Two hundred and nineteen relapses occurred on therapy, and 46 after discontinuation of therapy. Bone marrow was involved in the relapse in 71% and 67% of the two groups, respectively. Only 38/265 (14%) children with relapse were still alive at follow-up in January 1985. Of these, 16/219 (7%) had relapsed during therapy (median survival time after relapse 9 months) compared to 22/46 children (48%) with a relapse after cessation of therapy (median 43 months). The prognosis was better if relapse occurred after cessation of therapy and in children with isolated testicular relapse. Thirteen children were bone marrow transplanted, and 6 of these were alive at follow-up. It is concluded that children with ALL relapse have very bad prognosis with cytostatic regimens used today, especially if the bone marrow is involved.

Randomized multicentric Italian study on two treatment regimens for marrow relapse in childhood acute lymphoblastic leukemia

This paper reports the results of a multicentric randomized clinical trial on the treatment of first hematological relapse in childhood ALL. Induction treatment consisted of vincristine, adriamycin, L-asparaginase, and prednisone. Patients achieving complete remission were randomized to two maintenance regimens (A and B). Regimen A consisted of five different drug associations including VM26 and IDMTX in a sequential schedule; Regimen B was essentially classical Spiers schedule for the first year, followed by a milder treatment. Eighty-four of 102 evaluable patients (82%) achieved second complete remission. The two maintenance regimens were similar as regards duration of second complete remission (median duration A, 32 weeks; B, 37 weeks) and toxicity. Better results were obtained in patients relapsing after 12 months from suspension of treatment in first complete remission than in those relapsing within the first year off therapy (82.8% vs. 31.4%). In group A fewer CNS relapses were reported. The two regimens produced results similar to those reported by other authors. The good prognosis in patients relapsing at least 1 year after treatment suspension in first complete remission must be emphasized.

Modified Capizzi maintenance regimen in children with relapsed acute lymphoblastic leukaemia

Improved survival of children with acute lymphoblastic leukaemia who relapse during therapy has been reported using the Capizzi maintenance regimen. We have treated ten such patients, without histocompatible donors, with this regimen, which consisted of fortnightly doses of vincristine (1.5 mg/m2) and an escalating dose of intravenous methotrexate (90-470 mg/m2) followed 24 hours later by asparaginase (15,000 units). Remission of disease had been successfully achieved in all patients using conventional therapy prior to the start of maintenance treatment. Cerebrospinal fluid concentrations of methotrexate were estimated serially in several patients but remained relatively low despite dose escalation. It appears that additional intrathecal chemotherapy is therefore necessary. Treatment was generally well tolerated but there is concern about the incidence of neurotoxicity in patients who had previously received cranial irradiation and intensive intrathecal therapy. The median duration of bone marrow remission was only 35 weeks (range 18-50). Two patients who had not been receiving IT therapy had early isolated CNS relapses. In conclusion, it appears that contrary to early expectations this treatment approach is unlikly to offer a significantly better outlook for these patients, in whom the chance of early marrow relapse remains high.

Acute lymphoblastic leukemia in childhood

This article reviews those factors that have been responsible for progress in the past, describes current biologic and therapeutic approaches to ALL, and discusses those unresolved treatment issues that pose the major challenge for the future.

Yield of unpredicted bone-marrow relapse diagnosed by routine marrow aspiration in children with acute lymphoblastic leukaemia. A report from the Children's Cancer Study Group

1466 children with acute lymphoblastic leukaemia had routine bone-marrow aspiration at the end of each 84-day cycle of maintenance therapy. Relapses detected by routine bone-marrow aspiration were classified according to whether or not they could be predicted by clinical signs or peripheral blood counts. In the low-risk, moderate-risk, and high-risk leukaemic patients 0.4%, 0.5%, and 0.8%, respectively, of the total routine bone-marrow aspirations yielded an unpredicted bone-marrow relapse. 19.4% of relapses were detected by routine surveillance marrow aspirations before any clinical signs of relapse on physical examination or peripheral blood count. The median survival after relapse in the predicted group was significantly shorter than that in the unpredicted group, but the eventual outcome was the same in both groups, 95% of all patients dying within 24 months of relapse.

Bone marrow transplantation for diseases of childhood

Bone marrow transplantation in childhood is an established treatment modality for aplastic anemia, the acute and chronic leukemias, and severe combined immune deficiency. Recently, experience with this treatment has also been favorable with small numbers of children who have Wiskott-Aldrich syndrome, several types of inherited storage diseases, Fanconi's anemia, thalassemia, infantile malignant osteopetrosis, and selected cases of lymphoma and other solid tumors. The psychosocial impact and financial costs of bone marrow transplantation can be substantial. Multi-institutional, prospective, randomized trials that would compare transplantation and conventional therapy are necessary to establish the indications and precise timing for this procedure. Further development of monoclonal antibodies, a better understanding of the histocompatibility antigen systems, and improvement in pretransplantation conditioning regimens should increase the spectrum of effectiveness for bone marrow transplantation in the coming years.