Autologous bone marrow transplantation following high dose chemotherapy for the treatment of adult patients with acute myeloid leukaemia

24 adult patients with acute myeloid leukaemia (AML) were treated with intensive chemotherapy followed by autologous marrow rescue. The procedure was repeated twice in eight patients. 11 of 16 patients treated in first remission continue in first unmaintained remission (9-54 months, median 17 months). Eight patients treated at relapse or second remission have relapsed again and died within 14 months of their first autologous bone marrow transplant (ABMT). This form of intensification therapy would appear valuable for adult AML patients in first remission.     

Factors affecting the outcome of allogeneic bone marrow transplantation for adult patients with refractory or relapsed acute leukaemia

We evaluated the outcome of allogeneic bone marrow transplantation (BMT) for advanced acute myeloid leukaemia (AML) and acute lymphoblastic leukaemia (ALL) in 383 adult patients in nine Australian adult BMT centres between 1981 and 1997. The median overall survival for the group was 4.8 months, with an estimated 5-year survival of 18%. 28% of patients died of transplant-related toxicities within the first 100 d. Progressive disease was responsible for 48% of deaths. Multi-factor analysis demonstrated that AML (v ALL), disease status (second complete remission [CR2] v others), age (< 40 years) and duration of prior first complete remission (CR1) (> 6 months) were pre-transplant variables significantly associated with improved survival. Acute graft-versus-host disease (GVHD) of any grade reduced the rate of relapse in both AML and ALL, but only grades I-II were associated with improved survival. Both limited and extensive chronic GVHD were associated with increased survival. Only patients with AML in untreated first relapse or CR2, with a duration of CR1 > 6 months, or patients with T ALL, had a 5-year survival > 20%. Transplants for AML in induction failure or pre-B ALL in untreated first relapse or CR2 had an intermediate outcome, with 5-year survival of 10-20%. A 5-year survival of < 10% was observed for patients transplanted for ALL in induction failure or for pre-B ALL or AML in refractory first relapse or beyond CR2. These results suggest that for most adult patients with advanced acute leukaemia an allograft offers only a small chance of cure.     

Autologous bone marrow transplantation for acute myeloid leukemia using monoclonal antibody-purged bone marrow

We report our experience from a clinical trial of autologous bone marrow transplantation (ABMT) in the treatment of 30 patients with acute myeloid leukemia (AML) using monoclonal antibody (MoAb) and complement-treated bone marrow. All patients were in complete remission (CR) at the time of transplant: 6 patients were in first CR, 18 in second CR, and 6 in third CR. The median age of all patients was 42 years (range 11 to 57 years). For marrow ablation, 28 patients were treated with cyclophosphamide and total body irradiation. One patient was treated with busulfan and cyclophosphamide and one was treated with busulfan and VP-16. Each patient was then transfused with autologous bone marrow that had been harvested previously and treated with two MoAbs, PM-81 and AML-2-23, and rabbit complement. Median time to recovery of neutrophils (500/microL) was 30 days, and platelets (20,000/microL) was 45 days. Median time for initial erythrocyte engraftment, assessed by a flow cytometric reticulocyte assay, was 13 days. Median overall and relapse-free survival of first CR patients was at least 17.4 months post-ABMT and the 2- and 3-year actuarial overall and relapse-free survival was 67% (+/- 19%). Median survival for the 24 patients in second or third CR was 6.8 months post-ABMT and 9.3 months since CR; however, six patients survived disease-free from 16 to 61 months post-ABMT. For the second and third CR group it was observed that six patients (5 of the 6 survivors) showed "inversions," when their post-ABMT remission lasted longer than any previous one. Actuarial 2- and 3-year disease-free and overall survival of patients in second and third CR was 25% (+/- 9%) and 18% (+/- 9%), and 29% (+/- 9%) and 23% (+/- 9%), respectively. ABMT avoids the problems of graft-versus-host disease and of finding suitable donors for allogeneic marrow transplantation.     

Monoclonal antibody purging and autologous bone marrow transplantation in acute myelogenous leukemia in complete remission

A mouse monoclonal antibody (S4-7) reacting with human myelomonocytic cells has been previously shown to be suitable for bone marrow purging in selected acute myelogenous leukemia (AML) patients with S4-7 positive leukemic clonogenic cells at diagnosis. The results obtained in seven AML patients who underwent such a treatment, followed by autologous bone marrow transplantation (ABMT), are now reported. Six patients underwent ABMT in first complete remission (CR), one in second CR, after BAVC conditioning regimen. One patient died of infection 1 month after ABMT; in the other six a complete recovery of hemopoiesis was observed. In spite of S4-7 reactivity with normal myelomonocytic cells, a prompt recovery of granulopoiesis was however observed both in in vitro liquid culture and in vivo with a median time of 20 days to reach granulocyte values of 500 x 10(6)/l. The patient transplanted in 2nd CR relapsed 3 months after ABMT. Of the five evaluable patients transplanted in 1st CR, two relapsed 8 and 9 months post-ABMT while three remain in continuous CR at 35, 47, 57 months. Leukemic cells of two of the three patients with recurrent disease were studied at relapse and in both could be detected a significant percentage of S4-7 negative cells, detectable neither at diagnosis nor (one patient) at the time of first relapse after standard chemotherapy.     

Impaired glucose tolerance after autologous bone marrow transplantation

In this study we investigated glucose tolerance in relation to autologous bone marrow transplantation (ABMT). In 13 adult patients with acute myeloblastic (AML) or lymphoblastic (ALL) leukaemia in complete remission (CR), intravenous glucose tolerance test (IVGTT) was performed 1 month before and 6 months after ABMT. Patients with AML in CR received, as myeloablative therapy, cyclophosphamide combined with busulphan or total body irradiation (TBI). ALL patients received total body irradiation in combination with vincristine, daunorubicin, Ara-C, cyclophosphamide and prednisone. Before ABMT all patients, in spite of the intensive chemotherapy given for remission induction and consolidation, had a normal glucose tolerance. However, 6 months after the transplantation the k-value (rate of glucose elimination) for this group of patients had decreased (p less than 0.01). The trend towards impaired glucose tolerance was correlated with lower peak insulin values during IVGTT (p less than 0.05). Thus, the myeloablative therapy in connection with ABMT caused an impairment of pancreatic beta-cell function. No patient has hitherto developed clinical diabetes mellitus.     

Autologous bone marrow transplantation for acute leukaemia in remission

Between 1980 and 1985, 175 patients with acute leukaemia in first or subsequent complete remission (CR) were treated by chemotherapy or chemoradiotherapy followed by transfusion of autologous bone marrow cells that had been collected days or months previously. In 85 cases, autologous marrow cells were treated ex vivo with cytotoxic drugs or monoclonal antibodies with the intention of removing residual leukaemic cells. The actuarial relapse-free rate was 52% at 2 years. Of 89 patients autografted for acute non-lymphocytic (myeloid) leukaemia (ANLL), 60 were treated in first remission and 18 in second CR; their relapse-free rates at 2 years were 67% and 41% respectively (P less than 0.001). In contrast, of 77 patients autografted for acute lymphoblastic leukaemia (ALL), 32 were treated in first CR and 28 in second CR and their actuarial relapse free rates at 2 years were 56% and 55% respectively (P = NS). There was no significant difference in leukaemia relapse rates between patients autografted with purged and those autografted with non-purged marrow cells. These preliminary results suggest that autologous bone marrow transplantation may be valuable if offered to patients with ANLL in first CR or to patients with ALL in first or second CR but the need for marrow purging remains uncertain.     

High dose melphalan and total body irradiation with autologous marrow rescue in childhood acute lymphoblastic leukaemia after relapse

High dose melphalan (HDM 110-140 mg/m2) and total body irradiation (TBI, 10.5 Gy, single fraction) followed by infusion of autologous bone marrow (ABMT) was evaluated for toxicity and efficacy in 24 children with acute lymphoblastic leukaemia (ALL) in second (CR2) or third remission (CR3). Marrow was purged with Campath 1 in six children (four were children in CR3). All children had engraftment with a median of 30 days (range 18-70 days) to neutrophil count greater than 0.5 x 10(9)/l. Four children (16%) died from toxicity 1-4 months after autograft, two from pneumonitis, one from an intracerebral haemorrhage and one from sepsis. Apart from fever and mucositis the procedure was well tolerated. Nine of 17 children treated in CR2 remain in complete remission 6-72 months after ABMT (median 25 months). Seven of these have a follow-up of greater than 12 months. Three of the seven children treated in CR3 are alive 17, 22 and 29 months post ABMT. Seven children relapsed within 10 months (median 4 months) of the autograft. Only one relapse has occurred beyond 10 months. HDM and TBI followed by ABMT is a relatively well tolerated regimen and may contribute to survival in children with relapsed ALL.     

Allogeneic bone marrow transplantation versus chemotherapy for childhood acute lymphoblastic leukaemia in second remission

Thirty-six children with acute lymphoblastic leukaemia (ALL) in second remission were treated with conventional chemotherapy or with cyclophosphamide and fractionated total-body irradiation followed by an allogeneic bone marrow transplant; the choice of treatment was dictated by the availability of an HLA-identical sibling. The age, sex, clinical data at presentation of the disease and duration of first remission were comparable for the two groups of patients. In the bone marrow transplantation group two patients died of graft-versus-host disease and five of leukaemia. Ten patients survive, nine disease free, 13-53 months from second remission (6-51 months post-bone marrow transplantation). In the chemotherapy group 14 patients died of leukaemia (2-29 months from second remission) and five survive (22-34 months from second remission). The actuarial survival for patients with bone marrow transplantation is 48% at 4 years as compared with 22% for those of the chemotherapy group (P = 0.04); the actuarial probabilities of being in remission are 58 and 18% in the two groups respectively (P = 0.01). This study confirms that allogeneic bone marrow transplantation is superior to chemotherapy in patients in second remission with ALL and should be considered in the presence of an HLA-identical sibling.     

Results of therapy of 100 patients with acute leukemia--a retrospective unicenter 5-year analysis

The results of therapy in 100 patients who newly fell ill (68 AML, 32 ALL) with acute leukaemia were evaluated (1981 to 1985). The 5-year-survival chance of all patients is 15% for AML, 18% for ALL, first of all it is depending on the degree of remission obtained. The CR rate is nearly 43% (AML) and 66% (ALL), respectively, shows a dependence upon age and is impaired above all by a high early death rate (supportive therapy). With increasing aggressiveness the results of the remission induction therapy improve, as it becomes clear in a comparison with an evaluation of patients 1965-1980 (CR: 15-32%). Also in the postremission therapy the results of intensive forms of therapy are more favourable: 4 years recurrence-free survival after CR in autologous bone marrow transplantation 50%, in allogenic bone marrow transplantation 40%, in cyclic chemotherapy 17%, in oral permanent therapy 0%. Starting from these findings the present conception of the therapy of acute leukaemias is discussed in connection with the literature.     

Autologous bone marrow transplantation after a long first remission for children with recurrent acute lymphoblastic leukemia

Fifty-one children with acute lymphoblastic leukemia (ALL) in second or subsequent remission after a first remission of at least 24 months underwent purged, autologous bone marrow transplantation (ABMT). Bone marrow was harvested in remission and purged in vitro with monoclonal antibodies specific for leukemia-associated antigens. Ablative chemotherapy included cytarabine, teniposide, and cyclophosphamide followed by total body irradiation. Of the 51 patients treated between November 1980 and June 1991, 5 died of treatment-related complications, 18 relapsed, 1 died of a second tumor at 6.7 years, and 27 remained in continuous complete remission for a median of 39 months (range, 9+ to 124+). Event-free survival (EFS) (+/- SE) at 3 years after ABMT was 53% +/- 7%. Leukemia-free survival (LFS) was 58% +/- 8%. In multivariate analysis, the most significant predictors of EFS were duration of longest pre-ABMT remission and remission duration immediately before ABMT. For LFS, the most significant predictors were cell dose per kilogram of marrow reinfused and duration of longest pre-ABMT remission. We conclude that ABMT for this population is an effective therapy available to the majority of children with relapsed ALL.     

Biphenotypic acute leukaemia: a case series

Biphenotypic acute leukaemia (BAL) is a rare type of leukaemia. Whether patients with BAL should be treated with regimens designed for acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL) or both remain unclear. We have reviewed the clinical data for 31 BAL patients. Most patients co-expressed B-lymphoid and myeloid markers. No specific chromosomal abnormality was identified. The majority of the patients were treated with regimens devised for treating ALL. Seven patients were treated with regimens designed for AML. Complete remission (CR) rates of 78% and 57% were noted respectively. The overall survival probability at 2 years was 60%.     

Survival in 222 adult patients with acute leukaemia treated with intermittent combination chemotherapy programme

222 patients aged 15-59 years with acute leukaemia were treated with intermittent combination chemotherapy consisting of six 5-day courses of cytotoxic drugs as induction treatment followed by 3 years of maintenance therapy in patients who obtained complete remission (CR). CR was achieved in 50.3% of 161 patients (early deaths included) with acute myelogenous leukaemia (AML). The observed cumulative 5-yr survival rate (observation time 1-12.25 yr) calculated by the life table method was 12% in AML. Among patients who obtained CR, those aged 40-59 yr appeared to fare better than younger patients (5-yr survival: 24%). The M-3 subtype was an adverse prognostic factor. In acute lymphoblastic leukaemia (ALL) the CR rate was 83.6% and the observed cumulative 5-yr survival rate was 14%. Women fared better than men.     

Continuous complete remission in adult patients with acute lymphocytic leukaemia at a median observation of 12 years after autologous bone marrow transplantation

We report our long-term experience with autologous bone marrow transplantation (ABMT) for 32 adult patients with acute lymphocytic leukaemia (ALL) in second or later remission (CR), or in first CR but with high-risk. Bone marrow was purged with mafosfamide (n = 25) or with immunomagnetic beads and monoclonal antibodies (n = 7). Retrospective analysis showed that 12 out of 32 patients were in continuous complete remission (CCR) at a median of 143 months (range 66-181 months). A plateau was reached at 50 months and the disease-free and overall survival rates were both 37.5%. It was notable that durable CCR could be achieved for patients in second (three out of nine) or third (one out of six) CR. ABMT could produce durable CCR and the long-term outcome compared favourably with those reported for allogeneic transplantation.     

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.     

Treatment of acute lymphoblastic leukaemia in adults

Between 1972 and 1982, 112 consecutive previously untreated adults (aged 15-69 years, median 26) commenced therapy for acute lymphoblastic leukaemia (ALL) at St Bartholomew's Hospital. The first 63 patients entered into the study received initial treatment which comprised four cycles of adriamycin and vincristine, prednisolone and L-asparaginase with the first cycle (OPAL). In 1978, six cycles were given, with escalating doses of adriamycin and cyclophosphamide from cycle 3 (HEAV'D). Central nervous system (CNS) prophylaxis incorporated intrathecal methotrexate and cytosine arabinoside with cranial irradiation. Maintenance chemotherapy consisted of 6-mercaptopurine, cyclophosphamide and methotrexate for 3 years. Results obtained with the OPAL and HEAV'D regimens were not significantly different. The overall complete remission (CR) rate was 66% (73/111), factors correlating unfavourably with achievement of CR being advanced age (P less than 0.001) and L3 morphology/B-ALL immunophenotype (P less than 0.01). Fifty-three patients have relapsed, the bone marrow being the primary site in 43. Extramedullary relapse alone occurred in 10 (seven CNS, two testicular and one skin). Only three of the 64 patients who had complete CNS prophylaxis subsequently relapsed in the CNS as an isolated site. One patient died in CR, 19 remain in continuous CR between 2.5 and 10.5 years. The median duration of remission of the 73 patients who achieved CR was 18.5 months, factors correlating favourably with duration of CR being low blast cell count at presentation (P less than 0.002) and common ALL immunophenotype (P less than 0.04). Twenty-four patients remain alive, with a median survival of all patients of 18 months. Long-term survival is possible for approximately 20% of adults with ALL treated relatively intensively.     

Intensive cytotoxic therapy followed by autologous bone marrow transplantation for non-Hodgkin's lymphoma of high-grade malignancy

Fourteen patients with non-Hodgkin's lymphoma (NHL) of high-grade malignancy were treated with cyclophosphamide and total body irradiation followed by autologous bone marrow transplantation (ABMT). All patients were pretreated with conventional chemotherapy. Three of four patients with drug-resistant disease achieved complete remission (CR), but relapse occurred within six months. Four patients in partial remission (PR) achieved CR; one died because of sepsis, two relapsed within six months, and one is still in CR 28+ months later. Six were treated in CR, five in first CR, and one in second CR. From these six patients (who received this treatment as consolidation therapy), five are in unmaintained CR seven to 31+ months after ABMT (one patient died of a secondary illness). There were two therapy-related deaths, both in patients with a poor clinical condition. Toxicity of this treatment was mild for those receiving transplants who were in better condition. These preliminary results suggest that intensive cytoreductive therapy followed by ABMT may improve disease-free survival in patients in NHL of high-grade malignancy in CR.     

Autologous bone marrow transplantation for acute myeloid leukemia following in vitro treatment with neuraminidase and monoclonal antibodies

Although monoclonal antibodies (MoAbs) to CD15, especially PM-81, react with leukemic blasts from the majority of patients with acute myeloid leukemia (AML), a small subset of patients have cells that are CD15 negative or dim. We determined previously that neuraminidase will increase the reactivity of PM-81 with AML blasts, as well as blasts from many patients with acute lymphoblastic leukemia (ALL). In this report, we describe the laboratory results and clinical course of the first patient with AML whose harvested bone marrow was treated with neuraminidase prior to MoAbs and complement treatment. Neuraminidase increased the percentage of the patient's leukemia cells that reacted with PM-81 from 18% to 90% and more than doubled the percentage of AML blasts that were lysed by PM-81 and complement. The patient suffered no acute toxicity, engrafted rapidly, and was transfusion independent by day 21 post-ABMT. This report demonstrates the probable safety and efficacy of pretreatment of bone marrow with neuraminidase, and increases the number of patients with AML or ALL who may benefit from ABMT using marrow purging with MoAb to CD15.     

Marrow matrix metalloproteinases (MMPs) and tissue inhibitors of MMP in acute leukaemia: potential role of MMP-9 as a surrogate marker to monitor leukaemic status in patients with acute myelogenous leukaemia

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) were demonstrated to have important implications in the progression and invasiveness of many malignant disorders. In contrast, the biological significance of these molecules in human leukaemias is not clear. We determined the levels of MMP-2, MMP-9, TIMP-1 and TIMP-2 in the bone marrow of 37 patients with acute myelogenous leukaemia (AML) and 18 patients with acute lymphoblastic leukaemia (ALL) before chemotherapy. Nineteen bone marrow donors served as normal controls. After chemotherapy, sequential measurements were done during the course in 19 AML patients. The levels of TIMP-1 and TIMP-2 were significantly higher and MMP-9 levels were significantly lower in the AML and ALL patients than in the normal controls. MMP-2 levels were higher in ALL, but not AML patients, compared with controls. Moreover, the levels of marrow MMP-2 and MMP-9 did not parallel the numbers of leukaemic blasts in the peripheral blood. MMP-9 levels were significantly lower in the AML patients who achieved a complete remission (CR) than in those who did not (8.71 +/- 8.15 ng/ml vs 26.13 +/- 27.75 ng/ml, P < 0.05). The AML patients with lower MMP-9 levels (< or = 4.4 ng/ml) tended to have longer survival time than those with higher levels (> 12 months vs 4 months, P = 0.12). In addition, MMP-9 levels in the AML patients at CR rose to the same range as the controls, but dropped again at relapse, demonstrating a close relationship of marrow MMP-9 with disease status of AML. Therefore, we conclude that the level of marrow MMP-9 may be a useful surrogate marker for monitoring disease status in AML and propose it as a potential prognostic factor.     

Acute leukaemia in Jehovah's Witnesses

The refusal of Jehovah's Witnesses with leukaemia to accept transfusion provides a major clinical challenge because of the myelosuppressive effects of chemotherapy. Experience in treating five such patients is described. Two patients with acute lymphoblastic leukaemia (ALL) achieved remission following chemotherapy, the first without transfusion support, the second, a minor, receiving transfusion under a court order; the first patient remains in remission 5 years later, whereas the second subsequently relapsed and died. Of three patients with acute myeloid leukaemia (AML), two received chemotherapy: one died of anaemia during induction chemotherapy whereas the second eventually consented to transfusion but died of refractory leukaemia. The third patient died of anaemia despite erythropoietin. We feel Jehovah's Witnesses should not be denied antileukaemic therapy if they fully understand the risks involved. Minimizing phlebotomy, use of antifibrinolytic agents and growth factors may make chemotherapy feasible, especially in ALL where remission may be induced with less myelosuppressive agents. The outlook for those with AML treated with conventional chemotherapy appears poor; alternative approaches to treatment should be considered in these patients.     

Autologous bone marrow transplantation using marrow incubated with Asta Z 7557 in adult acute leukemia

The sensitivity of human myeloblastic leukemic (CFU-L) and normal hemopoietic stem cells (CFU-GM and BFU-e) to Asta Z 7557 (INN Mafosfamide) was studied with regard to autologous bone marrow transplantation (ABMT) with cleansed marrow for consolidation therapy in adult patients with acute leukemia (AL) in remission. Establishment of the dose-response curves for CFU-GM (n = 37), BFUe (n = 11), and myeloblastic CFU-L (n = 9) demonstrated a wide range of sensitivity from patient to patient for all three progenitors. Whereas CFU-L, CFU- GM, and BFU-e grown in semisolid cultures disclosed similar sensitivities to Asta Z 7557, long-term culture (LTC) studies (n = 41) indicated a higher resistance of early progenitors. In an effort to achieve a maximum tumor cell kill and yet spare a sufficient amount of normal stem cells to ensure consistent engraftment, we defined the optimal dose for marrow cleansing as the dose sparing 5% CFU-GM (LD95). This dose was established from a preincubation test (PIT) realized on a 10-mL marrow aspirate taken 15 days before marrow collection in each individual patient. Twenty-four adult patients while in remission of AL (20 in complete remission, four in partial remission) were consolidated by cyclophosphamide 60 mg/kg X 2 and total body irradiation at 10 Gy followed by ABMT with marrow cleansed by Asta Z 7557 according to the specification described above. Patients were divided in two groups: group 1, unfavorable prognosis (11 patients); group 2, standard prognosis [13 patients in first complete remission (CR)]. All patients engrafted on leukocytes (median day for recovery to 10(9)/L: day 30), patients with ALL recovered faster than patients with ANL (median day 19 v 34). Similarly, recovery of platelets to 50.10(9)/L occurred sooner in patients with ALL (median day 67, range day 23 through 90) whereas three patients with acute nonlymphoblastic leukemia (ANLL) in group 2 had to be supported with platelet transfusions for more than one year. In group 1, six patients had recurrent tumor within six months; three patients died from toxicity with no evidence of tumor. Two patients are still disease-free with a short follow-up (nine and ten months). In group 2, two patients died from toxicity with no evidence of leukemia three and 16 months post-ABMT. One patient with a M5 ANLL and one patient with ALL relapsed at six and 15 months, respectively. Nine patients have remained in CR or are disease-free with a median follow-up of 22 months.(ABSTRACT TRUNCATED AT 400 WORDS)