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.     

Relapse after first cessation of therapy in childhood acute lymphoblastic leukemia: A 10-year follow-up study

The outcome of 171 children with ALL who relapsed for the first time after elective cessation of therapy (1–86 mo) and followed over 10 years (median 60 mo; range 1–232 mo) has been evaluated. One hundred and three patients relapsed in the bone marrow (BM), 29 in the testis (T), 21 in the central nervous system (CNS), 14 in the BM plus another site and 4 in other sites. Second remission was achieved in 97% of patients (97% BM, 100% T, 90% CNS, respectively) with reinduction schedules including three or more drugs. All but 4 out of 100 patients who relapsed in the BM received cranial reprophylaxis with intrathecal CT alone or CT plus radiotherapy. Seven patients in second CR underwent allogeneic bone marrow transplantation from an HLA matched sibling. The overall survival was 34% and disease-free survival (DFS) probability at 100 years was 22%. A second relapse was observed in 73% of patients. Forty children are alive in second continuous remission and 24 are alive after a second or subsequent relapse. Patients with isolated T relapse showed a significant better outcome than those with BM or CNS involvement. Most patients (62%) with isolated BM relapse showed a further disease recurrence in BM, and DFS was shorter when relapse occurred within 12 months from off-therapy. Eighty-two patients in second CR stopped the treatment a second time and showed a survival and DFS probabilities, respectively, of 69% and 43%. Thus, children with ALL who relapse after cessation of therapy still have a high risk of further late relapses and should be treated with intensive chemotherapy and CNS reprophylaxis. BMT must be considered for all patients relapsing in the BM within 12 months from off-therapy. © 1995 Wiley-Liss, Inc.     

Treatment of relapsing acute lymphoblastic leukemia in childhood. III. Experiences with 54 first bone marrow,nine isolated testicular,and eight isolated central nervous system relapses observed 1985-1989

Of 54 children with acute lymphoblastic leukemia (ALL) and first hematological recurrence observed between 1985 and 1989, 31 relapsed while still on treatment and 23 after cessation of therapy. Of the former, only one survived. Of the latter, 11 children survived after a minimum follow-up of 25 months. During the same period, a first isolated testicular relapse was observed in nine boys, of whom six survived, and an isolated CNS relapse in eight patients, of whom three survived. As a rule, survivors of a bone marrow or testicular relapse were doing well while those surviving a CNS relapse had considerable neuropsychological sequelae. These results, compared with those of two preceding studies, suggest that with intensification of front-line treatments, it becomes more difficult to rescue children who relapse, particularily those with a bone marrow relapse while on therapy. © 1994 Wiley-Liss, Inc.     

Testicular relapse in childhood acute lymphoblastic leukaemia in Malaysia, 1967–82

From 1967–82,9 children with testicular relapse (TR) of acute lymphoblastic leukaemia (ALL) were diagnosed out of 99 boys treated, an incidence of 9.1%. The median time from the onset of ALL until diagnosis was 28 months (range 3–41 months). All were asymptomatic; six were detected on routine examination while three were diagnosed only on biopsy. Routine biopsy prior to stopping chemotherapy is useful in detecting occult TR. Biopsies should be done on both the testes regardless of the clinical findings. The age, leucocyte count and hepatosplenomegaly at diagnosis of ALL were not found to be significant factors in influencing relapse. Eight-children were in bone marrow remission at the time of TR, but three had preceding or concurrent meningeal leukaemia while in the other five the testis was the first and only site of relapse. Radiotherapy was effective in local disease control but failed to prevent bone marrow relapse in all except two patients despite continuation of chemotherapy. The median time from onset of TR until bone marrow relapse was 7 months (range 3–13 months) and the median time until death, was 11 months (range 6–18 months). The frequency of testicular relapse may be related to the intensity of either the initial induction therapy or the consolidation chemotherapy. Further studies are required to determine whether the incidence of testicular relapse will decline with more intensive early treatment.     

Hematopoietic stem cell transplantation after first marrow relapse of non-T, non-B acute lymphoblastic leukemia: a pediatric oncology group pilot feasibility study

BACKGROUND: Relapsed acute lymphoblastic leukemia (ALL) in children is associated with a poor outcome, especially for those patients whose relapse occurs during the first 36 months after diagnosis. The best therapy for these patients is not known. This study was designed to evaluate the feasibility of enrolling children with recurrent ALL in a standardized treatment protocol that included receipt of a hematopoietic stem cell transplant (HSCT). PROCEDURE: Eligible patients with a bone marrow relapse of non-T, non-B ALL underwent a common induction and consolidation followed by receipt of either an allogeneic HSCT from a human leukocyte antigen (HLA)-identical sibling or an autologous HSCT purged with B-4 blocked ricin. A common conditioning regimen was used for all patients. RESULTS: Twenty-eight patients from eight institutions were enrolled. Fourteen patients did not receive a transplant during the study, because of toxicity (4), relapse (1), inadequate purging (1), and parental or physician preference for an alternative donor transplant (8). Six patients received allogeneic HSCTs. Five of them have remained in remission for a median of 78 months. Eight patients received autologous HSCTs purged with B4-blocked ricin. Four have remained in remission for a median of 94 months. Of the nine patients who received alternative donor transplants, only two remain in remission. CONCLUSION: We conclude that well designed and controlled prospective studies are necessary to define the role of HSCTs in children with recurrent ALL. In order to be successful, such studies must have the full support of participating centers. Autologous HSC transplantation may have a role in the treatment of relapsed ALL, but further studies are needed.     

Ex vivo chemopurging of autologous bone marrow with 4-hydroperoxycyclophosphamide to eliminate occult leukemic cells. Laboratory and clinical observations

The application of autologous bone marrow transplantation (ABMT) in treating acute leukemias in children has been limited by the presence of residual occult viable leukemic cells in the marrow cell suspension. One approach to this problem is the ex vivo treatment ("purging") of the autograft to eradicate these tumor cells yet spare the normal lymphohematopoietic stem cells. Initial studies of acute myeloid leukemia (AML) in a rodent model demonstrated that incubation with 4-hydroperoxycyclophosphamide (4HC), a congener of cyclophosphamide and an active alkylating agent in aqueous solution, could effectively eliminate viable AML cells from marrow cell suspensions without apparent toxicity to normal stem cells. We have conducted clinical trials of ABMT with 4HC-treated marrow in children with acute leukemia in remission; marrow was collected, treated ex vivo with 4HC (100 micrograms/ml), and cryopreserved in liquid nitrogen until reinfusion. Children received pre-ABMT conditioning with either high-dose cyclophosphamide and total body irradiation (CY-TBI) for acute lymphocytic leukemia (ALL) or high-dose busulfan and cyclophosphamide (BU-CY) for AML. Of nine children who underwent ABMT with 4HC-treated marrow for ALL in second complete remission (CR2), all relapsed (eight in the marrow, one in the central nervous system) at a median of 5 months (range, 2-17) after ABMT and all have died with relapsed ALL or as a consequence of its treatment. Twenty-nine children with AML (five in CR1, 24 in CR2) received autografts with chemopurged marrow at a median remission duration of 3 months (range, 2-15). Three patients died from sepsis during aplasia; 10 children (one in CR1 and nine in CR2) relapsed with AML at a median of 7 months (range, 2-23) after ABMT, for an actuarial relapse rate of 47%. Sixteen patients with AML (four in CR1, 12 in CR2) are in unmaintained remission at a median of 16 months (range, 6-102) after ABMT, for an actuarial disease-free survival of 49%. Although ABMT with 4HC-treated marrow appears to have a limited role in the treatment of children with ALL who lack a suitable related donor, the results in AML are encouraging and compare favorably with both syngeneic and allogeneic BMT in similar groups of patients.     

Autologous bone marrow transplantation in children with acute lymphoblastic leukemia

We report 25 children with acute lymphoblastic leukemia (ALL) treated with purged autologous bone marrow transplantation (ABMT) at a single center. Two children with high-risk ALL were transplanted in first remission and 23 with relapsing ALL were transplanted in second (n = 21) or third (n = 2) remission. There was no procedure-related mortality. The median time to engraftment (i.e. to reach a polymorphonuclear cell count of 0.5 x 10(9)/l) was 25 days (range 16-45 days). Seven children relapsed, four within five months after ABMT: 18 of 25 children (72%) are in continuous complete remission after a median follow-up period of 50 months (range 5-71 months). The predicted long-term disease-free survival is 65% in the whole group and 61% in those transplanted after relapse. Relapse-free children returned to normal activities within three months after ABMT. The major side effects were development of cataract and gonadal insufficiency. We consider the results promising, but our data do not allow comparison with results reported from treatment with chemotherapy alone, since some of our patients were referred from other centers and represent a selected patient group. Long-term follow-up of well-defined patient populations is necessary to evaluate the effect of ABMT.     

Outcome after relapse in an unselected cohort of children and adolescents with Ewing sarcoma

BACKGROUND: Survival after relapse in patients with Ewing sarcoma is very poor and this retrospective study attempts to identify of prognostic factors predicting survival after relapse. PROCEDURE: A total of 191 patients with localised Ewing sarcoma were registered in the ET-2 trial of the United Kingdom Children's Cancer Study Group (UKCCSG). All patients received standardised primary treatment with chemotherapy and surgery and or radiotherapy as local modality treatment. Sixty-four patients who relapsed are included in this report. Treatment at relapse was variable and included chemotherapy, surgery, radiotherapy and high dose therapy (HDT) or megatherapy with peripheral stem cell transplantation (PBSCT) or autologous bone marrow transplantation (ABMT) in various combinations. A subgroup of patients had only non-specific symptomatic treatment at relapse. Both univariate and multivariate methods were used to investigate variables affecting survival after relapse. RESULTS: The overall actuarial median survival from relapse for all patients was 14 months (95% CI 11-16 months). Univariate analysis showed that males had a longer survival (median, 16 months vs. 11 months); patients who relapsed while on treatment did worse (median, 3 months vs. 16 months) and patients who had a longer disease-free interval (DFI) prior to relapse had a better outcome (DFI <1 year, median survival = 3 months; DFI 1-2 years, survival = 8 months; DFI > 2 years, median survival = 24 months, P < 0.001). Multivariate analysis confirmed that duration of first remission was the only factor associated with longer survival after relapse. CONCLUSIONS: These data suggest that although aggressive therapy may delay disease progression after relapse for some children, the course of the disease after relapse is usually fatal. International co-operative studies are needed to evaluate new strategies.     

High-dose melphalan, vincristine, and total-body irradiation with autologous bone marrow transplantation in children with relapsed neuroblastoma: a phase II study

Seven children with neuroblastoma who had relapsed on or after conventional therapy (3 originally stage IV, 3 stage III, 1 stage II) were entered on a study of "massive therapy" with purged autologous bone marrow rescue. In 5 patients attempts were made to reinduce remission with alternative chemotherapy, and a partial or complete response was achieved in 3. The massive therapy regimen comprised melphalan, vincristine, and total-body irradiation. Of 6 patients with measurable disease, all showed objective response to high-dose therapy (5 partial, 1 complete remission), but the median duration of remission was only 5 months (range 1/2 to 10). One patient remains disease-free at 18 months post graft. This patient was the only one treated in second complete remission. These data confirm the high response rate achieved by high-dose melphalan, total-body irradiation regimens, but it appears unlikely that a single high-dose chemoradiotherapy procedure will cure patients after relapse, particularly if they are unresponsive to conventional salvage regimens. Such protocols may, however, have a role as consolidation in first remission. The use of double-autograft procedures is an alternative that warrants further investigation in patients with relapsed neuroblastoma.     

Intermittent chemotherapy and BCG in continuation therapy of children with acute lymphocytic leukemia.

Continuation therapy using intermittent chemotherapy and BCG inoculation was commenced in 28 children with acute lymphocytic leukemia (ALL) immediately after remission induction and "CNS prophylaxis." At a median followup time of 17 months, 71% remain in total remission and 86% in bone marrow remission. Complications of the therapy were minimal. Major infections occurred on two occasions and there were no deaths in remission. Neutropenia, "minor" infections and postponement of chemotherapy occurred most often during the first three courses of treatment. There were no local or systemic BCG infections. Tuberculin sensitivity was tested in 25 patients. It was positive in 17 of 18 patients in total remission and all four patients with only CNS relapse, and was negative prior to relapse in three patients who developed bone marrow disease.     

Intermittent chemotherapy and bcg in continuation therapy of children with acute lymphocytic leukemia

Continuation therapy using intermittent chemotherapy and BCG inoculation was commenced in 28 children with acute lymphocytic leukemia (ALL) immediately after remission induction and “CNS prophylaxis.” At a median followup time of 17 months, 71% remain in total remission and 86% in bone marrow remission. Complications of the therapy were minimal. Major infections occurred on two occasions and there were no deaths in remission. Neutropenia, “minor” infections and postponement of chemotherapy occurred most often during the first three courses of treatment. There were no local or systemic BCG infections. Tuberculin sensitivity was tested in 25 patients. It was positive in 17 of 18 patients in total remission and all four patients with only CNS relapse, and was negative prior to relapse in three patients who developed bone marrow disease.     

Bone marrow chromosomes in acute lymphoblastic leukaemia: A long-term study

The bone marrow chromosomes of 25 children with acute lymphoblastic leukaemia (ALL) were examined at diagnosis before treatment, during remission, and in 12 cases, also during relapse. Follow-up was for at least six years. At diagnosis, 17 patients had a major population of chromosomally abnormal cells and of these 11 had identifiable clones. The commonest abnormality was hyperdiploidy. Eight patients had predominantly normal cells, but four of these had a minor abnormal clone. In remission, some samples were completely normal but, when pooled, remission samples had a minor population of chromosomally aberrant cells which were rarely clonal. The incidence of structural abnormalities was the same in patients who ultimately relapsed and those who remained in first remission at the end of the study, but the presence of hyperdiploid cells and/or clones in remission was more frequently associated with subsequent relapse. Relapse patterns were of two kinds: in three patients there was a return of the chromosomal abnormalities seen at diagnosis; in six others, chromosomal features in relapse were distinct from those at diagnosis. It is suggested that relapse associated with distinct chromosomal features may represent malignant transformation of a previously unaffected cell line. While chromosomal abnormalities seen prior to treatment can be related to the leukaemic event alone, abnormalities seen in remission and in relapse may result partly from drug and X-ray treatment. The relative importance of treatment and other factors to chromosomal change in ALL is discussed.     

Fludarabine, cytarabine, G-CSF and idarubicin (FLAG-IDA) for the treatment of relapsed or poor risk childhood acute leukemia

The prognosis of relapsed acute leukemia or chronic leukemia in acute blast crisis is poor and new chemotherapeutic regimens could be useful for these patients. Six relapsed acute lymphoblastic leukemia (ALL), nine relapsed acute myeloblastic leukemia (AML), one chronic myelomonocytic leukemia (CMML) and one chronic myeloid leukemia (CML) in acute blast crisis between three to 18 years (median 10 years) received fludarabine, cytarabine, G-CSF and idarubicin (FLAG-IDA) chemotherapy (CT). Five of the AML relapses were after bone marrow transplantation (BMT) and four were recurrent relapses. At the end of the second course only three patients (2 AML, 1 ALL) were in complete remission (CR). Of the three patients in CR, one patient with AML had her first donor lymphocyte transfusion (DLT) on the 7th day of the second FLAG-IDA course and she is disease-free on the 30th month of the second remission. The remaining two patients were transplanted from unrelated donors in a BMT center abroad on the 5th and 8th month of the last remission and both died with BMT-related complications. Out of 25 courses, seven resulted in fatal infections. The regimen was ineffective in B-cell ALL as in acute blastic crisis of CMML and CML. We could not evaluate the remission-inducing effect accurately in most of the patients due to induction failure. FLAG-IDA appears to be a myelotoxic therapy for relapsed or poor risk leukemia in a developing country. It is not cost-effective; dose modifications or a regimen without IDA may be tried if there is an available marrow donor.     

Bone marrow chromosomes in acute lymphoblastic leukaemia: a long-term study.

The bone marrow chromosomes of 25 children with acute lymphoblastic leukaemia (ALL) were examined at diagnosis before treatment, during remission, and in 12 cases, also during relapse. Follow-up was for at least six years. At diagnosis, 17 patients had a major population of chromosomally abnormal cells and of these 11 had identifiable clones. The commonest abnormality was hyperdiploidy. Eight patients had predominantly normal cells, but four of these had a minor abnormal clone. In remission, some samples were completely normal but, when pooled, remission samples had a minor population of chromosomally aberrant cells which were rarely clonal. The incidence of structural abnormalities was the same in patients who ultimately relapsed and those who remained in first remission at the end of the study, but the presence of hyperdiploid cells and/or clones in remission was more frequently associated with subsequent relapse. Relapse patterns were of two kinds: in three patients there was a return of the chromosomal abnormalities seen at diagnosis; in six others, chromosomal features in relapse were distinct from those at diagnosis. It is suggested that relapse associated with distinct chromosomal features may represent malignant transformation of a previously unaffected cell line. While chromosomal abnormalities seen prior to treatment can be related to the leukaemic event alone, abnormalities seen in remission and in relapse may result partly from drug and X-ray treatment. The relative importance of treatment and other factors to chromosomal change in ALL is discussed.     

Treatment of refractory and relapsed Hodgkin's disease: intensive chemotherapy and autologous bone marrow or peripheral blood stem cell support

Thirty-three patients with recurrent or refractory Hodgkin's disease were treated with high-dose cyclophosphamide, BCNU, and etoposide and supported with either autologous bone marrow or peripheral blood stem cells or both. Peripheral blood stem cells were comparable to bone marrow in supporting the recovery of hematopoiesis. Twenty-five patients (76%) were in complete remission following this therapy of whom 13 have subsequently relapsed. Twelve remain alive and disease free from 10 to 47 months. The Kaplan-Meier estimate of disease-free survival at 28 months for the entire 33 patients is 32% (95% confidence interval, 13-50%). Poor outcome in six patients was associated with bone marrow involvement by Hodgkin's disease at the time of peripheral blood stem cell collection. These six patients' survival, disease-free survival, the duration of complete remission were all significantly worse than for the 27 patients who were supported with bone marrow (n = 23), peripheral blood stem cells (n = 2), or both (n = 2), and whose marrows were free of disease at the time of stem cell collection. These data demonstrate that intensive therapy with autologous transplantation can produce extended disease-free survival for some patients with advanced Hodgkin's disease and that peripheral blood stem cell support can effectively be used for hematopoietic reconstitution. However, our observations also suggest that with this preparative regimen, bone marrow involvement at the time of peripheral blood stem cell collection is predictive for a poor outcome and alternate approaches to treatment should be considered for this subset of patients.     

Successful autologous bone marrow transplant for relapsed Ki-1 lymphoma

We report on a 16 year old girl with relapsed Ki-1 lymphoma and a very poor prognosis. The initial manifestation was multiple bone metastases and lymphadenopathy. The patient achieved remission with modified adriamycin, bleomycin, vincristine, daunomycine therapy. However, 14 months after the completion of therapy, relapse occurred in a new cervical lymph node on the left side. After preparation with chemotherapy and total lymphoid irradiation (TLI) the patient underwent autologous bone marrow transplantation (A-BMT). Ki-1 lymphoma shows clinically diverse symptoms, but hematopoietic stem cell transplantation should be performed in relapsed cases. It may be effective to give TLI followed by A-BMT for patients such as ours who have lymph node involvement without bone marrow metastasis.     

Value of Routine Bone Marrow Examination for Detection of Bone Marrow Relapse in Children with Standard Risk Acute Lymphoblastic Leukemia

The value of routine bone marrow examination (RBME) in children during and after treatment for standard risk acute lymphoblastic leukemia (SR-ALL) was Investigated. The clinical symptoms and peripheral blood findings at the time of bone marrow relapse of 28 children were reviewed and compared with those of 28 matched controls in continuous complete remission. Five (45%) children with bone marrow relapse during maintenance therapy and six (35%) after cessation of cytostatic treatment were asymptomatic at the time of relapse. Signs indicative of relapse duriny treatment were lymphoblast cells in the peripheral blood, thromhocytopenia, hepatomegaly, anemia, or leukopenia in decreasing order of frequency. Afer cessation of treatment these signs were lymphoblasts in the peripheral blood, hepatomegab, splenomegaly, thrombocytopenia, or leukocytosis. Except for one case with thrombocytopenia, no signs suspicious for relapse were found in the control groups. When each sign was evaluated separately only the presence of lymphoblasts in peripheral blood and hepatomegaly were significant symptoms for relapse after cessation of treatment. The mean percentage of lymphoblasts in the bone marrow at the time of relapse was significant& lower for patients with an unpredicted relapse (46.8%) than patients with clinical and/or laboratory evidence of relapse (79.5 %). When lymphoblasts were present in the peripheral blood the percentage of lymphoblasts in the bone marrow was always more than 40%, both during and after cessation of treatment. These data suggest a relation between clinical and laboratory symptom and progression of the disease. It is concluded that 467% of relapses are detected by RBME in the absence of clinical or laboratory symptoms. This early detection may have a positive prognostic influence with more effective treatment for relapsed ALL.     

Lack of benefit of early detection of relapse after completion of therapy for acute lymphoblastic leukemia

BACKGROUND: Although most pediatric oncologists obtain routine blood counts in patients who have completed treatment for acute lymphoblastic leukemia (ALL), the value of this practice is unproven. We therefore sought to determine if detection of relapse by blood counts before the onset of symptoms provided any clinical benefit. PROCEDURES: We performed a retrospective review of 72 patients with ALL who suffered isolated or combined hematologic relapses after the completion of therapy. We compared attainment of second remission and survival after relapse among patients who were asymptomatic and diagnosed by routine blood count, those who had symptoms suggestive of relapse and were diagnosed at the time of a scheduled follow-up, and those whose relapse was diagnosed because of the appearance of symptoms. RESULTS: Only 11% of patients who suffered a relapse were asymptomatic at the time of relapse and diagnosed solely by routine blood counts. There were no significant differences in the survival distributions for the three groups of patients. CONCLUSIONS: In this cohort of patients with relapsed ALL, we found no evidence that detection of relapse by routine blood counts before the onset of symptoms leads to a better outcome.     

Treatment of childhood acute lymphoblastic leukemia with intermediate-dose cytosine arabinoside and adriamycin

Eight pediatric patients with acute lymphoblastic leukemia (ALL) were treated with intermediate-dose cytosine arabinoside (ID-AraC, 1 g/m2) in combination with adriamycin except one patient. Of the eight patients, four refractory to the initial induction therapy and one in bone marrow relapse gained complete remission with two to three cycles of this therapy. Four of the five patients have been in continuous remission for 4 to 24 months with the maintenance therapy of monthly administration of ID-AraC. One patient in central nervous system (CNS) relapse has continued in remission from CNS leukemia after two cycles of the therapy. Side effects of ID-AraC and adriamycin were generally mild to moderate and tolerable in all children. These results suggest that the use of ID-AraC and adriamycin might prove effective in the treatment of ALL refractory to other regimens.     

Allogeneic bone marrow transplantation in acute lymphoblastic leukemia of children. Analysis of prognostic factors. GEGMO (Bone Marrow Study Group) study

Sixty-five children with acute lymphoblastic leukemia (ALL) underwent allogenic bone marrow transplantation (BMT) from an HLA identical donor, following cytoreduction with cyclophosphamide and total body irradiation (TBI): 15 were transplanted in 1st remission, 43 in 2nd and 7 in 3rd or in 4th. The Kaplan Meier estimate of surviving disease free at 4 years post BMT was 49.9% and the probability of continued remission at 4 years was 63.3%. Fourteen patients relapsed between 90 and 690 days (mean: 240 +/- 88) post BMT. The other causes of BMP failure included: graft versus host disease, veno-occlusive disease and sepsis. No interstitial pneumonitis has been reported. Patients who had a relapse while on chemotherapy had a higher probability of relapse than those who had a relapse while off therapy (p less than 0.01). We conclude that allogeneic BMT is the treatment of choice for children with ALL in second hematologic remission, the interval between diagnosis and first relapse being the most significant prognostic factor. Patients with poor prognosis might benefit from a more intensive chemotherapy/total body irradiation schedule or a BMT earlier in the course of their disease.