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

Long-term outcome after intensive therapy with etoposide, melphalan, total body irradiation and autotransplant for acute myeloid leukemia

Intensive therapy and autologous blood and marrow transplantation (ABMT) is an established post-remission treatment for acute myeloid leukemia (AML), although its exact role remains controversial and few data are available regarding longer-term outcomes. We examined the long-term outcome of patients with AML transplanted at a single center using uniform intensive therapy consisting of etoposide, melphalan and TBI. In all, 145 patients with AML underwent ABMT: 117 in first remission, 21 in second remission and seven beyond second remission. EFS and OS were significantly predicted by remission status (P<0.0001). For transplantation in first remission, 8 year EFS and OS were 55% (95% CI, 44-64%) and 62% (95% CI, 50-72%), respectively. By multivariate analysis, only age (P=0.04) and cytogenetic risk group (P=0.006) influenced OS. For patients transplanted in second remission, 8 year EFS and OS were 30% (95% CI, 9-55%) and 36% (95% CI, 13-60%), respectively. No pre-transplant variables significantly predicted outcome. None of the seven patients who underwent ABMT beyond second remission or in early relapse were long-term survivors. ABMT can provide long-term antileukemic control for patients with AML in first remission. For patients in second remission approximately 30% can achieve cure with ABMT, and this option may be preferable to alternate donor allogeneic stem cell transplantation.

Treatment of acute myeloid leukaemia in younger patients

The survival of AML in younger patients has improved in the last 20 years, as a consequence of a more intensive approach to treatment. Seventy-five to eighty percent of patients will enter complete remission, so the main challenge is to prevent relapse. Several trials have assessed the value of allogeneic or autologous transplantation. When these trials have been assessed by careful statistical methods, the advantage of transplant overall is difficult to detect. Intensive consolidation can deliver a similar survival, of which high-dose Ara-C has been widely adopted, but other intensive schedules appear equivalent. It is not known how many treatment courses are required. Patients are at differing risks of relapse which may influence the choice of treatment. In trials where a risk profile is available, and where a donor versus no-donor analysis is performed, there appears to be little robust evidence to support transplant in good or poor risk disease, although the experience in the latter groups is not unanimous. Standard risk patients may be the subgroup who deliver survival benefit, but since chemotherapy continues to improve, there remains some uncertainty. It is possible that technical improvements in transplantation, such as peripheral blood as a source of stem cells, may remove this uncertainty.

Overview of autologous stem cell transplantation

There has been a dramatic increase in the number of autologous peripheral blood stem cell transplants over the last decade. Faster recovery of cell counts, lesser transplant morbidity, shorter hospital stay and reduced cost compared with marrow autografts have been the main advantages of autologous peripheral blood cell over marrow transplants. In this paper we attempt to review the advances in the biology and mobilization of stem cells, and focus on clinical results of autologous peripheral stem cell and marrow transplants for disease specific sites such as breast cancer, myeloma, autoimmune diseases, germ cell tumors, the acute and chronic leukemias, the non-Hodgkin's lymphomas and Hodgkin's disease. We also discuss transplant related complications, gene therapy and the different methods of purging. This review was intended for autologous peripheral stem cell transplants, however, unavoidably, it also discusses autologous marrow transplantation and aspects common to both procedures.

Randomised comparison of addition of autologous bone-marrow transplantation to intensive chemotherapy for acute myeloid leukaemia in first remission: results of MRC AML 10 trial. UK Medical Research Council Adult and Children's Leukaemia Working Parties

BACKGROUND

Three strategies are used to prevent relapse in patients with acute myeloid leukaemia in first remission. Most of those with suitable donors are offered allogeneic haemopoietic-stem-cell transplant. Other patients may receive intensive chemotherapy or autologous transplantation; we undertook this randomised prospective trial to assess which is the better option.

METHODS

After three courses of intensive chemotherapy, bone marrow was harvested from patients (<56 years of age) in remission who lacked an HLA-matched sibling donor. These patients were then randomised to receive, after one more course of chemotherapy, no further treatment (n=191) or an autologous bone-marrow transplant (BMT) after preparation with cyclophosphamide and total-body irradiation (n=190). Outcome comparisons were by intention to treat with adjustment for the most important risk factors for relapse.

FINDINGS

381 patients were randomised (38% of those eligible). Of the 190 patients allocated autologous BMT, 126 received it. On intention-to-treat analysis the number of relapses was substantially lower in the autologous BMT group than in the group assigned no further treatment (64/190 [37%] vs 101/191 [58%], p=0.0007), resulting in superior disease-free survival at 7 years (53 vs 40%; p=0.04). These benefits were observed in all risk groups and age-groups. There were more deaths in remission in the autologous BMT group than in the no further treatment group (22 [12%] vs 7 [4%], p=0008). In children (<15 years) and patients with good-risk disease, survival from relapse in the no further treatment group was 35% and 38% at 2 years. There was an overall survival advantage in the autologous BMT group at 7 years (57 vs 45%, p=0.2).

INTERPRETATION

The addition of autologous BMT to four courses of intensive chemotherapy substantially reduces the risk of relapse in all risk groups, leading to improvement in long-term survival. The good chance of salvage for children or patients with good-risk disease who relapse from chemotherapy, and the mortality, morbidity, late effects, and expense of autologous BMT, suggest that delay of autograft until second remission in these two groups may be appropriate.

Gene transfer in haematological malignancy

Although gene transfer was first suggested to treat inherited monogenic disorders, at present most clinical protocols are intended to treat patients with malignant disease. Although current vector technologies profoundly limit the potential therapeutic applications of gene transfer, the technique is already being successfully used to complement longer established therapies. This article reviews current and forthcoming applications of gene transfer to treat haematological malignancies.

Gene transfer and therapeutic drug monitoring

During the next decade, gene therapy will evolve from a medical curiosity into an essential component of medical practice. One of the elements necessary for this transition will be the development of simple and accurate ways of monitoring both the vectors used to transfer the genes of interest and the function of the genes themselves. This article reviews the difficulties in achieving these aims and describes ways in which the technology of gene transfer offers a novel means of monitoring current therapies.

Autologous or allogeneic bone marrow transplantation compared with intensive chemotherapy in acute myelogenous leukemia. European Organization for Research and Treatment of Cancer (EORTC) and the Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto (GIMEMA) Leukemia Cooperative Groups

BACKGROUND

Allogeneic or autologous bone marrow transplantation and intensive consolidation chemotherapy are used to treat acute myelogenous leukemia in a first complete remission.

METHODS

After induction treatment with daunorubicin and cytarabine, patients who had a complete remission received a first course of intensive consolidation chemotherapy, combining intermediate-dose cytarabine and amsacrine. Patients with an HLA-identical sibling were assigned to undergo allogeneic bone marrow transplantation; the others were randomly assigned to undergo autologous bone marrow transplantation (with unpurged bone marrow) or a second course of intensive chemotherapy, combining high-dose cytarabine and daunorubicin. Comparisons were made on the basis of the intention to treat.

RESULTS

A total of 623 patients had a complete remission; 168 were assigned to undergo allogeneic bone marrow transplantation, and 254 were randomly assigned to one of the other two groups. Of these patients, 343 completed the treatment assignment: 144 in the allogeneic-transplantation group, 95 in the autologous-transplantation group, and 104 in the intensive-chemotherapy group. The relapse rate was highest in the intensive-chemotherapy group and lowest in the allogeneic-transplantation group, whereas the mortality rate was highest after allogeneic transplantation and lowest after intensive chemotherapy. The projected rate of disease-free survival at four years was 55 percent for allogeneic transplantation, 48 percent for autologous transplantation, and 30 percent for intensive chemotherapy. However, the overall survival after complete remission was similar in the three groups, since more patients who relapsed after a second course of intensive chemotherapy had a response to subsequent autologous bone marrow transplantation. Other differences were also observed, especially with regard to hematopoietic recovery (it occurred later after autologous transplantation) and the duration of hospitalization (it was longer with bone marrow transplantation).

CONCLUSIONS

Autologous as well as allogeneic bone marrow transplantation results in better disease-free survival than intensive consolidation chemotherapy with high-dose cytarabine and daunorubicin. Transplantation soon after a relapse or during a second complete remission might also be appropriate.

Long-term outcome of postremission chemotherapy for adults with acute myeloid leukemia using different dose-intensities

The long-term results of postremission chemotherapy for 122 consecutive, unselected adults (15-65 years) with acute myeloid leukemia (AML) were assessed in two sequential prospective studies involving an identical 3/7-type induction regimen, and in those achieving remission, another course for early consolidation using 1 day of daunorubicin instead of three. Forty-one patients reaching C.R. during the first study period, were treated with an intensive ablative maintenance ("IM") program for a period of 9 months. They were randomized to either 6 cycles of induction-type regimen or to 6 cycles of an alternating-type regimen consisting of high-dose (HD)-Ara C/AMSA or 5-azacytidine/AMSA every 6 weeks. There was no difference in disease-free survival (DFS) or survival. Results are compared with 27 patients reaching C.R. on the subsequent protocol where IM was replaced by intensive, short-term consolidation ("IC") using 1 cycle of intermediate-dose Ara C plus AMSA and 1 cycle of HD-AraC/AMSA. Fifteen patients received both courses of IC as scheduled, 12 refused the second cycle. There was no significant difference in DFS or survival. Seventeen out of the 122 patients refused either IM or IC following early consolidation ("refusals"). They received no further treatment and served as control. Fourteen percent of all patients underwent autologous or allogeneic bone marrow transplantation (BMT) at different stages of their disease, equally distributed amongst the IM and IC-group. Median DFS was 3.3 months in the refusal group, 12.4 months in the IM-group, and 18.4 months in the IC-group when censored for BMT (p = 0.01) with 6%, 12%, and 40% in C.C.R. at 50 months. Accordingly, median survival was 5.4, 20 and 47 months (p = 0.001) with 6%, 15%, and 45% of patients alive at 5 years. There was a definite trend (p = 0.14) for a higher proportion of long-term survivors in the IM-group when BMT was performed (not censored), while long-term survival was identical in the IC-group whether BMT was considered for analyses (not censored) or not (censored). Median follow-up for both studies is 5.6 years, the longest, 10 years. In conclusion, progressive increments in the intensity of postremission therapy yields in a graded, significant improvement of remission duration and survival.

Gene marking and autologous bone marrow transplantation

If residual cancer cells in harvested bone marrow could be marked and subsequently detected in patients at relapse, valuable information would be obtained about the source of recurrent disease after autologous marrow transplantation. If normal progenitor cells were also marked, the study would provide useful data on the susceptibility of these human cells to gene transfer and their capacity to express newly introduced genes. We transferred the neomycin-resistance gene (NeoR) into bone marrow cells harvested from 20 children with acute myeloid leukemia (n = 12) or neuroblastoma (n = 8) in clinical and cytological remission using a retrovirus vector. The cells were then returned to the patients as part of an autologous bone marrow transplantation protocol. Two AML and three neuroblastoma patients have relapsed. In all, the resurgent cells contained the NeoR marker by analysis with PCR. These results prove that so-called remission marrow can contribute to relapse in patients who receive autologous transplants. The gene marking technique is now being used to evaluate techniques of pretransplant purging.

Cell culture assessment of hematopoietic progenitors in bone marrow transplantation

A number of cell culture techniques are now available to evaluate clonogenic hematopoietic progenitors as well as cell populations that represent an interactive network of cells with regulatory capabilities. Although clonogenic cells in allografts do not appear to be correlated with the time to recovery, they seem to predict their time to engraftment in autografts. However, these cell populations are likely to be only surrogate measurements because a reduction by various purging techniques does not seem to alter the ability of autografts to reestablishing hematopoiesis. Currently, it is not known whether or not these differences may relate to differences in the preparative regimens, graft-versus-host disease prophylaxis, or other differences in the management, such as administration of high concentrations of various antiviral agents. It is also now possible to measure growth factor production following the transplant procedure and to correlate the availability of endogenous factors and recovery after a transplant. Under normal conditions, the activity levels appear to return to normal values within 20-30 days, whereas in patients with late engraftment one may observe prolonged elevation of growth factors. If confirmed, this would suggest that in bone marrow transplants a delayed return is more related to reduced progenitor cells rather than a deficiency of growth factors.

The prognostic significance of the CD34 antigen in acute myeloid leukaemia

The prognostic value of CD34 expression on leukaemic blast cells was assessed in 38 patients with acute myeloid leukaemia. Nineteen patients had more than 10% CD34 positive blast cells. Median survival for the CD34 positive patients was 125 days and for the CD34 negative patients the median survival has not yet been reached at day 575 (p = 0.06). Of those patients who received intensive chemotherapy, CD34 positive patients (n = 13) had a median survival of 150 days while for CD34 negative patients (n = 14) the median survival has not yet been reached (p = 0.01). Adjustment for age and pre-existing myelodysplastic syndrome did not affect the correlation of CD34 positivity with survival (p = 0.02). Over the period of observation (median 10 months, range 2-19 months) the relative risk of death was 5 times greater for the CD34 positive patients. This study suggests that CD34 expression is an adverse prognostic marker, independent of age and pre-existing myelodysplasia.

Bone marrow transplantation for acute non-lymphoblastic leukemia

Most results obtained by different study and analytic designs favor that matched allogeneic BMT is superior to chemotherapy in young adults with ANLL in first remission. The place of ABMT is more difficult to assess and requires further study both compared to chemotherapy and allogeneic BMT. Furthermore, the question of purging needs further study in a controlled fashion. For older patients the choice is more difficult. Transplant related mortality increases with age which makes ABMT an attractive alternative to allogenic BMT. However, recent advances in prophylaxis and treatment of transplant related complications such as cytomegalovirus interstitial pneumonia and veno-occlusive disease of the liver might increase long-term survival after allogeneic BMT in older patients. The role of matched unrelated donors in the treatment of ANLL is unresolved but this procedure should probably be reserved for relatively young patients in second complete remission or later.

Allogeneic bone marrow transplantation in multiple myeloma. European Group for Bone Marrow Transplantation

BACKGROUND AND METHODS

In contrast to autologous bone marrow transplants for hematologic cancers, allogeneic transplants contain no tumor cells that might cause a relapse. We report the results of such allogeneic bone marrow transplantation using HLA-compatible sibling donors in 90 patients with multiple myeloma performed in 26 European centers between 1983 and 1989.

RESULTS

At the time of the most recent follow-up, 79 months after the start of the study, 47 patients were alive and 43 were dead. The rate of complete remission after bone marrow transplantation was 43 percent for all patients and 58 percent for the patients who had engraftment. The actuarial survival at 76 months was 40 percent. The median duration of relapse-free survival among patients who were in complete remission after bone marrow transplantation was 48 months. The stage of the disease at diagnosis and the number of treatment regimens tried before bone marrow transplantation were predictive of the likelihood of complete remission after engraftment. There were trends toward longer survival among patients who were responsive to treatment before bone marrow transplantation, patients with Stage I disease at diagnosis, and patients who had received only first-line treatment before transplantation, as compared with those who were not responsive, those with Stage II or III disease at diagnosis, and those who had received three or more lines of treatment, but the differences in these factors were not statistically significant. Two post-transplantation factors predicted better long-term survival: complete remission after engraftment and grade I graft-versus-host disease, rather than grade II, III, or IV.

CONCLUSIONS

Allogeneic bone marrow transplantation with the use of HLA-matched sibling donors appears to be a promising method of treatment for some patients with multiple myeloma.

Post consolidation therapy for adult patients with acute myeloid leukaemia

One hundred and sixteen adult patients aged 14-73 with previously untreated acute myeloid leukaemia received induction and consolidation chemotherapy with daunorubicin, cytosine arabinoside and thioguanine. Two novel approaches to post consolidation therapy have been investigated. Patients aged 50 years or less who had no suitable matched allogeneic donor were considered for autologous bone marrow transplantation (BMT) using bone marrow which had been cultured in vitro for 14 d. Patients over the age of 50 years with normal bone marrow cellularity and peripheral blood count were treated with a single oral dose of busulphan 100 mg/m2 (without BMT rescue) 3 months following the completion of consolidation therapy. Eighty-seven patients (75%) achieved a complete remission. Of 70 patients who completed consolidation therapy, 40 were aged less than or equal to 50 years and 30 were greater than 50 years. Forty-three patients went on to receive post consolidation therapy in first CR (autologous BMT 12, allogeneic BMT 7, busulphan therapy 24). The event-free survival at 4 years was 47% for autologous BMT, 34% for allogeneic BMT and 45% for busulphan-treated patients. The survival for the older cohort of patients who received post consolidation therapy with single dose busulphan therapy was encouraging, and this agent should be considered for future post consolidation strategies.

Autologous bone marrow transplant in the treatment of acute leukaemia

For a minority of patients with acute leukaemia, usually in children and predominantly with acute lymphoblastic leukaemia, existing chemotherapy protocols are curative. For a minority of the remaining group myeloablative chemoradiotherapy supported by allogeneic marrow from an HLA-matched donor can cure the disease. Major efforts are being made to free the potential benefit of this approach from the limitations imposed by the associated immune-biological complications, and limited donor availability. In the last decade the resurgence of autologous transplantation in remission has been a major new source of hope for further progress. Many groups have produced encouraging results, which now that they have substantial follow-up, suggest that this approach is altering the normal pattern of relapse. Almost all the experience, however, while producing consistent results, at least in AML, is anecdotal. The possibility of selection bias, particularly by the time-censoring effect, cannot be excluded, and prospective controlled trials are needed. The data available suggest which investigations could be expected to yield clear results. Other questions, particularly whether or not to purge the marrow, are only practical to investigate in well-defined patient subgroups. The opportunity to identify predictive parameters in this new clinical setting, using the more powerful techniques now becoming available should not be missed. National and international trials now in progress will yield crucial data in the next 2 or 3 years.

Practical aspects and diagnostic significance of in vitro manipulation of progenitors in human acute myeloid and lymphoid leukaemia

Since their introduction in the early seventies, in vitro culture techniques for human acute leukaemia cells have been modified and improved considerably. Primarily, this is the result of the availability of the recombinant haematopoietic growth factors (HGFs). It is now possible to evaluate HGF responses of acute leukaemia cells in colony and DNA synthesis assays under fully defined conditions. In this chapter we summarize the current insights into the growth properties of human acute leukaemia progenitor cells and evaluate the potential significance of the application of in vitro clonogenic assays for refining the diagnosis of acute leukaemia, for detecting minimal residual disease and for monitoring therapy.

Long-term outcome of adults with acute myelogenous leukaemia: results of a prospective, randomized study of chemotherapy with a minimal follow-up of 7 years

In a prospective study running between 1981 and 1983, a group of 156 adult (under 60 years of age) patients with de-novo acute myelogenous leukaemia were randomly assigned to receive a daunorubicin, cytosine arabinoside and thioguanine combination or a regimen containing lower dosages of these drugs but also containing etoposide and vindesine. Patients who entered complete remission received maintenance therapy for 2 years. The survival and remission duration curves of the two groups were exactly superimposable and for this long-term analysis all patients have been considered together. The follow-up times range between 84 and 104 months. Actual survival at 7 years is 15% (95% confidence intervals 9-20%), with a stable curve thereafter. Actual probability of continuous complete remission at 7 years is 22% (95% C.I. 13-31%) with a stable curve beyond that point. These findings, similar to those of the few other studies of chemotherapy with comparable follow-up times, suggest that only a small fraction of adult patients become long-term survivors, irrespective of the precise type or amount of antineoplastic agents administered.

Autologous blood stem cell transplantation for chronic granulocytic leukaemia in transformation: a report of 47 cases

Forty-seven patients with chromosome Philadelphia-positive (Ph1) chronic granulocytic leukaemia (CGL) in transformation underwent autologous transplantation of peripheral blood stem cells (ABSCT) collected at the original diagnosis before any treatment. They were treated with three consecutive strategies: single transplant (group I = 17 patients), double transplant (group II = 13 patients), double transplant followed by recombinant alpha interferon (group III = 17 patients). Forty-three patients were restored to a second chronic phase with a cytogenetic conversion (more than 10% Ph1-negative marrow metaphases) occurring in 14 of the 29 evaluable patients. Most patients had a recurrent transformation occurring 2-43 months after ABSCT and finally eight patients are still alive in second chronic phase 4-49 months after ABSCT (median = 24 months). The actuarial median duration of second chronic phase was 3 months, 10 months and 18 months for group I, group II and group III patients (P less than 0.0001). The encouraging results observed for group III patients prompt us to propose ABSCT for patients in chronic phase with initial prognostic factors, suggesting that recombinant alpha interferon will not be effective if administered as front-line therapy.

Autologous bone marrow transplantation in acute myeloid leukemia in first remission: first Dutch prospective study

We have prospectively compared the values of autologous BMT (auto-BMT) and allogeneic marrow transplantation (allo-BMT) in patients (age 15-60 years) with acute myeloid leukemia (AML) who attained complete remission (CR) following remission-induction therapy. In 90/117 cases CR was reached. In 32 of those complete responders auto-BMT was undertaken and in 21 eligible cases HLA-matched allo-BMT. AML relapse was the predominant cause of failure after auto-BMT (17/32). The incidence of relapse after allo-BMT was 6/21. Patients treated with auto-BMT and allo-BMT have an overall survival of 37% and 66% at 3 years posttransplant (P = 0.05). Survival of the nongrafted complete responders is less than 10%. Allo-BMT in adult patients with AML in first complete remission provides a superior outcome when directly compared with the results of auto-BMT.

Autologous bone marrow transplantation in the treatment of acute myeloid leukemia: the Dartmouth experience and a review of literature

Autologous bone marrow transplantation is increasingly being investigated as a treatment for patients with acute myelogenous leukemia. Review of the literature demonstrates that much of the data are incomplete. Most reports contain small numbers of patients, making analysis of any particular regimen difficult to assess. The morbidity and mortality of the procedure appear to be substantially less than that seen in the allogeneic setting. The major complications relate to problems with engraftment. Recovery of platelet production to normal levels is frequently cited as delayed, and in some patients, does not occur. This phenomenon may be heightened by marrow manipulation during purging or posttransplant drug therapy. It is not known if this is a problem related to stem cells or related to the changes in the hematopoietic microenvironment. The results of autologous bone marrow transplantation for patients with acute myeloid leukemia suggest that, as with standard chemotherapy, there is little survival benefit when patients are in relapse at the time of transplantation. There are few long-term survivors, and relapse within 5 months is the rule. It should be noted that the vast majority of the studies reported here have used marrow that has not been treated in an attempt to remove occult leukemia cells. The use of purged bone marrow has not yet been adequately studied. In patients in second or subsequent remission, ABMT appears to offer a chance for long-term survival not seen with present second-line standard chemotherapy regimens and should be considered a viable option for patients under the age of 55. The results to date do not define whether marrow purging is beneficial, and most studies being carried out at the present time are not evaluating this question. The majority of studies are examining different methods of purging. The result of our study in patients in second and third remission using in vitro purging of bone marrow with monoclonal antibodies PM-81 and AML2-23 are encouraging, as are the studies of purging with 4-HC. The Cancer and Leukemia Group B has just begun a study for patients with AML in second remission using the protocol we piloted at Dartmouth. We are also evaluating the feasibility of using this therapy in patients at the time of first relapse, as studies in the allogeneic setting have suggested the results are similar to those achieved in second remission (60).(ABSTRACT TRUNCATED AT 400 WORDS)

High-dose chemotherapy with noncryopreserved autologous bone marrow transplantation for acute myeloid leukemia in first complete remission

Seven patients with acute myeloid leukemia (AML) in first complete remission were treated with escalating high doses of cyclophosphamide, etoposide, and cytosine arabinoside (Ara-C). In all patients autologous bone marrow preservation was performed prior to therapy. Bone marrow was stored in blood bags in a refrigerator for 48-72 h at 4 degrees C and then reinfused over a central line. All patients had a full hematological recovery. The mean time of neutropenia (neutrophils less than 500/microliters) was 14 days (range 9-24 days), and the mean time of thrombocytopenia (platelets less than 20,000/microliters) was 9 days (range 7-11 days). The nonhematological toxicity was tolerable with mild to moderate nausea/vomiting, mucositis and diarrhea, and so far not dose-limiting. Six patients remain in complete remission 17+, 9+, 5+, 5+, 4+, and 1+ months after autotransplantation. One patient relapsed 8 months after autotransplantation. High-dose chemotherapy with noncryopreserved bone marrow autotransplantation may be useful as intensified consolidation for patients with AML in first complete remission.

Comparison of allogeneic or autologous bone marrow transplantation and chemotherapy in patients with acute myeloid leukaemia in first remission: a prospective controlled trial

Eighty-five adult patients under the age of 50 years with acute myeloid leukaemia (AML) were entered into a prospective controlled study conducted to compare the effectiveness of allogeneic or autologous bone marrow transplantation and intensive chemotherapy for patients in first complete remission. Sixty-one patients (72%) achieved complete remission then received a consolidation treatment. After consolidation, 58 patients who were still in remission were assigned to three different therapeutic modalities. Fifty-two patients were evaluable: 20 patients who had an HLA-identical sibling donor underwent allogeneic bone marrow transplantation within 3 months after achievement of complete remission; the other 32 patients were randomized to receive autologous bone marrow transplantation or intensive sequential chemotherapy. The actuarial risk of relapse at 3 years was 18% for the allogeneic patients, 50% for the autologous patients and 83% in the chemotherapy group. The difference was highly significant (P less than 0.0002). The disease-free survival was respectively 66% (95% confidence interval 41-85%), 41% (95% confidence interval 16-66%) and 16% (95% confidence interval 0-31%) (P less than 0.004). We conclude that allogeneic bone marrow transplantation is presently the best therapeutic approach for patients with AML in first complete remission.

Double autologous bone marrow transplantation for acute myelogenous leukemia in a patient treated for Hodgkin's disease

A 30-year-old man developed acute myelogenous leukemia nearly 3 years after treatment of Hodgkin's disease with radiation and three chemotherapy combinations. Remission was induced with one cycle of high-dose Ara-C therapy. Three cycles of consolidation chemotherapy were given. The patient then had two autologous bone marrow transplants, the first after conditioning with 5 Gy total body irradiation, the second after Melphalan 140 mg/m2. The procedures were well tolerated, although hematological reconstitution was very slow after the second autotransplant. The patient has been disease-free for over 4 years. Such patients may be more vulnerable to transplant-related complications because of their previous exposure to chemotherapy and radiation, which may damage several organs including the bone marrow. This report demonstrates that patients with secondary acute myelogenous leukemia may tolerate a double autotransplant procedure and achieve durable remissions.

Differential phthalocyanine photosensitization of acute myeloblastic leukaemia progenitor cells: a potential purging technique for autologous bone marrow transplantation

The potential value of sulphonated aluminium phthalocyanine (AISPc) as a purging agent for bone marrow autografts in acute myeloblastic leukaemia (AML) has been studied using in vitro clonogenic assays for normal (GM-CFC) and leukaemic (AML-CFC) progenitor cells. In nine out of 13 cases, the leukaemic blasts were found to be highly sensitive to AISPc. In six of the sensitive cases clonogenic assays revealed that only 2 +/- 1% of AML progenitor cells survived AISPc treatment under conditions which permitted a GM-CFC recovery of 60 +/- 11%. AISPc photosensitization was also shown to selectively eliminate the leukaemic cell line K562 from an in vitro model of minimal residual disease. Thus photosensitization using AISPc may be an effective method of purging marrow autografts in some cases of AML. Evaluation of the sensitivity of AML clonogenic cells at diagnosis may identify those patients in whom AISPc photo-purging may be of benefit at the time of an autologous bone marrow transplant.