Infection in the bone marrow transplant recipient and role of the microbiology laboratory in clinical transplantation.

Over the past quarter century, tremendous technological advances have been made in bone marrow and solid organ transplantation. Despite these advances, an enduring problem for the transplant recipient is infection. As immunosuppressive regimens have become more systematic, it is apparent that different pathogens affect the transplant recipient at different time points in the posttransplantation course, since they are influenced by multiple intrinsic and extrinsic factors. An understanding of this evolving risk for infection is essential to the management of the patient following transplantation and is a key to the early diagnosis and treatment of infection. Likewise, diagnosis of infection is dependent upon the quality of laboratory support, and services provided by the clinical microbiology laboratory play an important role in all phases of clinical transplantation. These include the prescreening of donors and recipients for evidence of active or latent infection, the timely and accurate microbiologic evaluation of the transplant patient with suspected infection, and the surveillance of asymptomatic allograft recipients for infection. Expert services in bacteriology, mycology, parasitology, virology, and serology are needed and communication between the laboratory and the transplantation team is paramount for providing clinically relevant, cost-effective diagnostic testing.     

Genomics of unrelated-donor hematopoietic cell transplantation.

Unrelated-donor hematopoietic cell transplantation is a proven curative modality for hematologic malignancies. The success of unrelated-donor transplantation has been achieved through a better understanding of the immunobiology of the HLA system and through more precise and comprehensive matching of donors and recipients. The extensive polymorphism of HLA genes confers important biological implications affecting engraftment, graft-versus-host disease and overall survival. Although more-complete HLA identity of the donor and recipient is associated with optimal transplant outcome, new information suggests that not every HLA disparity is functionally relevant. Future advances in unrelated-donor transplantation must include the identification of tolerable HLA mismatches, so that more patients may benefit from this therapeutic modality. Furthermore, the role of cytokine-gene polymorphisms and minor histocompatibility genes in transplant outcome requires investigation. Delineation of the function of these markers as transplantation determinants may provide alternative means for optimizing the results of hematopoietic cell transplantation.     

Recent Clinical Update of Acute Myeloid Leukemia: Focus on Epigenetic Therapies

Acute myeloid leukemia (AML) is a complicated disease characterized by genetic heterogeneity and simultaneous alterations in multiple genes. For decades, its only curative method has been intensive induction chemotherapy with or without allogeneic hematopoietic stem cell transplantation, and this approach cannot be applied to elderly patients, who make up more than 50% of AML patients. Recent advances in genomics facilitated the elucidation of various mutations related to AML, and the most frequent mutations were discovered in epigenetic regulators. Alterations to epigenetic modifications that are essential for normal cell biology, including DNA methylation and histone acetylation, have been identified. As epigenetic dysregulation is an important carcinogenic mechanism and some epigenetic changes are reversible, these epigenetic alterations have become targets for novel drug development against AML. This review summarizes the recent advances in epigenetic therapies for AML and discusses future research directions.     

Thiotepa,Fludarabine, and Busulfan Conditioning Regimen before T Cell–Replete Haploidentical Transplantation with Post-Transplant Cyclophosphamide for Acute Myeloid Leukemia: A Bicentric Experience of 100 Patients

Haploidentical stem cell transplantation (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) is an alternative treatment for acute myeloid leukemia (AML) patients who lack HLA-matched donors. Relapse after haplo-SCT remains a major concern, especially after nonmyeloablative conditioning regimens. Promising results were reported for TBF-based conditioning regimens (thiotepa, busulfan, and fludarabine) in patients transplanted from different categories of donors and for various disease types but not specifically in PT-Cy haplo-SCT for AML. Here we evaluate the outcome of 100 AML patients who received haplo-SCT with PT-Cy after TBF conditioning regimens (reduced-intensity conditioning, n = 77; myeloablative conditioning, n = 23) in 2 transplant programs. Cumulative incidences of grades III to IV acute and moderate or severe chronic graft-versus-host disease (GVHD) were 7% and 14%, respectively. NRM at 2 years was 28%, significantly influenced by disease status at haplo-SCT (first complete response [CR1] versus advanced AML: 16% versus 38%, P = .016) but not by conditioning intensity or age. The cumulative incidences of relapse at 2 years were 17% and 24% in CR1 and advanced AML, respectively (not significant). Progression-free survival, overall survival, and GVHD and relapse-free survival at 2 years were 67%, 71%, and 49% in CR1 patients, respectively, whereas comparative values in patients with advanced disease were 37%, 41%, and 32%. Our study suggests that TBF conditioning for PT-Cy haplo-SCT is safe and effective for AML patients in CR1. In patients with more advanced disease, the relatively low incidence of relapse seems counterbalanced by a high nonrelapse mortality, underlining the need for alternative strategies to decrease relapse risk, without increasing the intensity of conditioning regimen.     

Allotransplants for Patients 65 Years or Older with High-Risk Acute Myeloid Leukemia

The outcome of persons > 65 years with acute myeloid leukemia (AML) is poor. A transplant from an HLA-identical sibling or an HLA-matched unrelated donor can cure some of these patients but is associated with a substantial transplant-related mortality and a high relapse risk. We analyzed 185 subjects > 65 years with high-risk AML receiving conventional (n?=?42) or reduced-intensity (n?=?143) pretransplant conditioning and a transplant from an HLA-identical sibling (n?=?66) or a 10/10 loci HLA-matched unrelated donor (n?=?119). Two-year survival was 37%. Subjects with serious adverse events during before chemotherapy for their leukemia had a poor outcome after stem cell transplantation. Patients who had active leukemia or measurable residual disease (MRD) before transplantation had a worse outcome. Delayed hematologic recovery after induction or consolidation chemotherapy, high-risk AML genetics, donor–recipient HLA-DRβ3/4/5-DP mismatches, and history of cardiovascular disease were also correlated with survival in multivariate analyses. The 57 MRD-negative patients with few other adverse prognostic factors had an excellent outcome (2-year overall survival, 76%), whereas the 58 patients with detectable leukemia and more than 1 other additional factor fared poorly (2-year overall survival, 8%). These data indicate it is possible to identify persons > 65 years with high-risk AML likely to benefit from an allotransplant. Validation of this prediction is needed.     

Lung transplantation. State of the art

Lung transplantation is currently considered an established treatment for some advanced lung diseases. The beginning of experimental lung transplantation dates back to the 1940's when the Soviet Vladimir P. Demikhov performed the first lung transplants in animals. Two decades later, James Hardy performed the first lung transplant in humans. Unfortunately, the beginning of clinical lung transplantation was hampered by technical complications and the excessive toxicity of immunosuppressive drugs. Improvement in the surgical technique along with the development of more effective and less toxic immunosuppressive drugs has led to a better outcome in lunt transplant recipients. Donor selection and management before organ procurement play a key role in the receptor's outcome. Due to the shortage of donors, some institutions are using more liberal selection criteria, reporting satisfactory outcomes. The approach of the lung and heart-lung transplant patient is multidisciplinary and includes the cardiothoracic transplant surgeon, pulmonologist, anesthesiologist, and intensivist, among others. Herein, we review some relevant historical aspects and recent advances in the management of lung transplant recipients, including indications and contraindications, evaluation of donors and recipients, surgical techniques and peripost-operative care.     

Tissue typing in support of unrelated hematopoietic cell transplantation

The success of unrelated hematopoietic cell transplantation (HCT) for the treatment of hematologic malignancies has closely paralleled development of robust typing methods for comprehensive and precise donor-recipient matching. The application of molecular methods in clinical research has led to a more complete understanding of the immunogenetic barriers involving host-vs-graft (HVG) and graft-vs-host (GVH) reactions. Along with the development of less toxic transplant regimens, advances in the prevention and treatment of graft-vs-host disease (GVHD) and in the supportive care of the transplant recipient, improved HLA matching of potential unrelated donors has led to clinical results that begin to compare favorably with that of HLA-identical sibling transplants.     

Hematopoietic Stem Cell Transplantation in Adults with Acute Myeloid Leukemia

Hematopoietic stem cell transplantation (HSCT) is an integral part of the treatment of many patients with acute myeloid leukemia (AML). Despite extensive study, the appropriate role and timing of allogeneic and autologous transplantation in AML are poorly defined. This review critically analyzes the extensive literature, focusing on the recent advances, and provides practical recommendations for the use of HSCT in AML.     

Comparison of Autologous Stem Cell Transplantation versus Haploidentical Donor Stem Cell Transplantation for Favorable- and Intermediate-Risk Acute Myeloid Leukemia Patients in First Complete Remission

Stem cell transplantation (SCT) is an attractive postremission treatment option for patients with intermediate-risk acute myeloid leukemia (AML) and for some favorable-risk AML patients with additional nongenetic risk factors. Autologous SCT (auto-SCT) and haploidentical donor SCT (haplo-SCT) are the widely used alternatives in cases of a lack of a HLA-matched donor. However, limited data have been published on the direct comparison between these 2 transplant types. Based on the transplant database in our center, we conducted a retrospective study involving patients with favorable- and intermediate-risk AML in first complete remission (CR1), according to the National Comprehensive Cancer Network guideline. Patients with extramedullary disease or those achieving CR by more than 2 cycles were excluded. In total, 195 patients were included in the study, 88 of whom underwent auto-SCT and 107 haplo-SCT. In the entire cohort analyses the impact of high relapse incidence in the auto-SCT group was compensated by low nonrelapse mortality (NRM), which resulted in a comparable overall survival (OS) (79.0%?±?4.6% versus 80.1%?±?5.0%, P?=?.769) and relapse-free survival (RFS) (66.1%?±?5.2% versus 77.4%?±?4.8%, P?=?.079) compared with those observed in the haplo-SCT group. However, for patients with intermediate-risk AML, NRM was similar between the groups, and haplo-SCT exhibited superior survival. In case of post-SCT relapse, patients with intermediate-risk AML showed markedly inferior 3-year OS compared with that shown by patients with favorable-risk AML (23.3%?±?9.8% versus 60.8%?±?14.3%, P?=?.011). In the multivariate analyses, minimal residual disease (MRD) measured by flow cytometry and gene mutation status before transplantation were independent predictors for both OS and RFS. We concluded that both auto-SCT and haplo-SCT were acceptable options for postremission treatment of patients with favorable- and intermediate-risk AML. Haplo-SCT yielded a better outcome in patients with intermediate-risk AML, but the relapse after SCT still led to a poor outcome. Clearance of MRD before SCT could improve the prognosis after transplantation.     

Haploidentical Transplantation for Older Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome

Allogeneic stem cell transplantation with HLA-matched donors is increasingly used for older patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). It remains unclear if haploidentical stem cell transplantation (haploSCT) is a suitable option for older patients with this disease. We analyzed 43 patients with AML/MDS (median age, 61 years) who underwent a haploSCT at our institution. All patients received a fludarabine-melphalan–based reduced-intensity conditioning regimen and post-transplant cyclophosphamide-based graft-versus-host disease (GVHD) prophylaxis. Except for 1 patient who had early death, the remaining 42 patients (98%) engrafted donor cells. The cumulative incidences of grades II to IV and III to IV acute GVHD at 6 months were 35% and 5%, respectively, and chronic GVHD at 2 years was 9%. After a median follow-up of 19 months, 2-year overall survival, progression-free survival (PFS), and relapse incidence were 42%, 42%, and 24%, respectively. Best PFS (74% at 2 years) was seen in patients with intermediate-/good-risk cytogenetics, in first or second remission (hazard ratio, .4; P?=?.05), and with a younger donor (≤40 years; hazard ratio, .2; P?=?.01). In conclusion, these data suggest that haploidentical transplantation is safe and effective for older AML/MDS patients. Disease status, cytogenetics, and younger donor age are predictors for improved survival in older patients receiving a haploidentical transplant.     

Allocation to Matched Related or Unrelated Donor Results in Similar Clinical Outcomes without Increased Risk of Failure to Proceed to Transplant among Patients with Acute Myeloid Leukemia: A Retrospective Analysis from the Time of Transplant Approval

Clinical outcomes after allogeneic hematopoietic stem cell transplantation (allo-SCT) from unrelated donors (URDs) approach those of matched related donor (MRD) transplants in patients with acute myeloid leukemia (AML). Yet, available data fail to account for differences in pretransplantation outcomes between these donor selection strategies. In this regard, URD allo-HSCT is associated with longer waiting times to transplantation, potentially resulting in higher probabilities of failure to reach transplant. We retrospectively analyzed 108 AML patients accepted for first allo-HSCT from the time of approval to proceed to transplant. Fifty-eight (54%) patients were initially allocated to MRD, while URD search was initiated in 50 (46%) patients. Time to transplant was longer in patients allocated to a URD when compared with patients assigned to an MRD (median 142 days versus 100 days; p < .001). Forty-three of 58 (74%) patients in the MRD group and 35 of 50 (70%) patients in the URD group underwent transplantation (odds ratio [OR], 1.22; p?=?.63). Advanced disease status at the time of allo-HSCT approval was the only predictor of failure to reach transplantation in the multivariate analysis (OR, 4.78; p?=?.001). Disease progression was the most common cause of failure to reach allo-HSCT (66.7%) in both the MRD and URD groups. With a median follow-up from transplantation of 14.5 (interquartile range, 5 to 29) months, the 2-year estimate of overall survival (OS) from allo-HSCT was 46% in the MRD group and 57% in the URD group (p?=?.54). There were no differences in OS according to donor type allocation in the multivariate analysis (hazard ratio, 1.01; p?=?.83). When including patients from the time of transplant approval, 2-year OS was 39% in the MRD group versus 42% in the URD group. Our study suggests that allocation of AML patients to URDs may result in comparable clinical outcomes to MRD assignment without a significant increase in the risk of failure to reach transplant.     

Ostra białaczka szpikowa u osób w wieku podeszłym

The majority of patients with acute myeloid leukemia are elderly. The introduction of new more aggressive treatment regimens with allogeneic stem cell transplantation have resulted in improvement in clinical outcome of younger AML patients, but analogous improvement in older patients has not been realized. There is evidence that AML in elderly represents a biologically distinct disease that is more aggressive and less responsive to chemotherapy. The important task is to use prognostic factors and predictive modeling to distinguish patients who will benefit from intensive remission-induction approaches and allogeneic transplantation and others who should be managed with less aggressive strategies or novel agents.     

Hematopoietic Stem Cell Transplantation for Shwachman-Diamond Syndrome

We report the outcomes of hematopoietic stem cell transplantation (HSCT) for 52 patients with Shwachman-Diamond syndrome (SDS) who underwent transplantation between 2000 and 2017. The median age at transplantation was 11 years, and the median duration of follow-up was 60 months. The indication for HSCT was bone marrow failure (BMF; cytopenia or aplastic anemia) in 39 patients and myelodysplasia (MDS)/acute myelogenous leukemia (AML) in 13 patients. The donor type was an HLA-matched sibling for 18 patients, an HLA-matched or mismatched relative for 6 patients, and an HLA-matched or mismatched unrelated donor for 28 patients. Preparative regimens for BMF were myeloablative in 13 patients and reduced intensity in 26. At the time of this report, 29 of the 39 patients with BMF were alive, and the 5-year overall survival was 72% (95% confidence interval, 57% to 86%). Graft failure and graft-versus-host disease were the predominant causes of death. Preparative regimens for patients with MDS/AML were myeloablative in 8 and reduced intensity in 5. At the time of this report, only 2 of 13 patients were alive (15%), with relapse the predominant cause of death. Survival after transplantation for SDS-related BMF is better compared with historical reports, but strategies are needed to overcome graft failure and graft-versus-host disease. For SDS- related MDS or AML, transplantation does not extend survival. Rigorous surveillance and novel treatments for leukemia are urgently needed.     

Reduced-Intensity Allogeneic Transplant for Acute Myeloid Leukemia and Myelodysplastic Syndrome Using Combined CD34-Selected Haploidentical Graft and a Single Umbilical Cord Unit Compared with Matched Unrelated Donor Stem Cells in Older Adults

Haplo/cord transplantation combines an umbilical cord blood (UCB) graft with CD34-selected haploidentical cells and results in rapid hematopoietic recovery followed by durable UCB engraftment. We compared outcomes of transplants in older patients with acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes (MDS) who received either HLA-matched unrelated donor (MUD) cells or haplo/cord grafts. Between 2007 and 2013, 109 adults ages 50 and older underwent similar reduced-intensity conditioning with fludarabine and melphalan and antibody-mediated T cell depletion for AML (n?=?83) or high-risk MDS (n?=?26) followed by either a MUD (n?=?68) or haplo/cord (n?=?41) graft. Patient characteristics were similar for each graft source except for more minority patients receiving a haplo/cord transplant (P?=?.01). One half of the AML patients were not in remission. Two-year progression-free survival (PFS), overall survival (OS), and graft-versus-host disease–free relapse-free survival were 38%, 48%, and 32.1% for MUD and 33%, 48%, and 33.8% for haplo/cord transplants (P?=?.62 for PFS; P?=?.97 for OS; P?=?.84), respectively. Acute grades II to IV and chronic graft-versus-host-disease rates did not differ at 19.5% and 4.9% in haplo/cord compared with 25% and 7.4% after MUD (P?=?.53 and P?=?.62, respectively). Multivariate analysis confirmed no significant differences in transplant outcomes by donor type. Haplo/cord reduced-intensity transplantation achieves similar outcomes relative to MUD in older AML and MDS patients, making this a promising option for those without matched donors.     

Heart transplant candidates: factors influencing waiting list mortality

Cardiac transplantation is a successful treatment for end-stage heart disease. However the number of potential candidates is significantly greater then number of suitable organ donors. We reviewed the characteristics of new transplant candidates presenting for assessment for cardiac transplantation to the Irish Heart & Lung Transplant programme over a one year period. Of 44 patients referred for assessment, 24 (54.5%) were listed for cardiac transplantation. Six have died while awaiting transplantation, seven have been transplanted and eleven remain on the active transplant list. The six month survival rate on the transplant waiting list is 74%. Although the Irish system of organ donation has traditionally provided high organ donation rates in comparison with other countries, the demand for suitable heart donors exceeds supply. Newer methods of promoting and facilitating organ donation may prove beneficial in improving the number of donations and addressing the long waiting time for cardiac transplantation.     

Hematopoietic Stem Cell Transplant Recipients Surviving at Least 2 Years from Transplant Have Survival Rates Approaching Population Levels in the Modern Era of Transplantation

The health and outcomes of long-term survivors after hematopoietic cell transplant (HCT) are areas of evolving interest as short-term transplant outcomes improve. Because recent changes in transplant practice have likely changed the survivor population, we sought to assess the survival of a contemporary cohort of patients who were alive and free of disease 2 years after HCT. Data were extracted from first transplants documented between 2002 and 2011 in the Australasian Bone Marrow Transplant Recipient Registry on patients who received an allogeneic HCT for acute myeloid leukemia (AML), acute lymphoblastic leukemia, chronic myeloid leukemia (CML), non-Hodgkin lymphoma, and myelodysplastic syndromes or an autologous HCT for myeloma or lymphoma. Patients were included if they had survived at least 2 years without disease relapse or progression. Mortality rates were compared with standard Australian and New Zealand populations using relative-survival analysis. A total of 1562 allogeneic and 3822 autologous HCT patients were included, with a median follow-up of 5.6 years. Compared with a matched group of patients from our previous study from 1992 to 2001, the contemporary cohort of allogeneic HCT recipients was older and more likely to receive peripheral blood stem cells and from unrelated donors. Allogeneic HCT for AML increased, wheresa transplants for CML fell from 32% to 8%. Increasing use of reduced-intensity conditioning and unrelated donors was also seen. Long-term survival after allogeneic and autologous HCT were very similar to the previous 1992 to 2001 cohort despite changes in practice over time. Recipients of autologous HCT for myeloma demonstrated substantially lower overall survival than HCT for other indications with no clear plateau. Annual relative survival for survivors of allogeneic HCT was 96% to 99% of the general population but only 89% to 96% of the general population for recipients of autologous HCT. Late deaths were primarily due to nonrelapse causes after allogeneic HCT, but relapse or disease progression remained prominent for recipients of autologous HCT, particularly for myeloma. The management of late HCT effects is important to improve long-term survival of transplant recipients but should be tailored to the risks specific to the primary disease and transplant type. Future planning should account for the impact of the expected increase in transplant activity and number of survivors on resource utilization.     

KIR Donor Selection: Feasibility in Identifying better Donors

We previously reported that acute myelogenous leukemia (AML) transplants using killer cell immunoglobulin-type receptor (KIR) B haplotype better or best (≥2 B activating gene loci ± Cen B/B) unrelated donors (URDs) yield less relapse and better survival. In this prospective trial we evaluated 535 AML searches from 14 participating centers with centralized donor KIR genotyping for donor selection. This represented 3% to 48% of all AML searches (median 20%) per center, totaling 3 to 172 patients (median 22) per center. Donor KIR genotype was reported at a median of 14 days after request (≤26 days for 76% of searches). In 535 searches, 2080 donors were requested for KIR genotyping (mean 4.3 per search); and a median of 1.8 (range, 0 to 4.5) per search were KIR typed. Choosing more donors for confirmatory HLA and KIR haplotype identification enriched the likelihood of finding KIR better or best donors. The search process identified a mean of 30% KIR better or best donors; the success ranged from 24% to 38% in the 11 centers enrolling ≥8 patients. More donors requested for KIR genotyping increased the likelihood of identifying KIR better or best haplotype donors. Of the 247 transplants, 9.3% used KIR best, 19% used KIR better, and 48% used KIR neutral donors while 24% used a non–KIR-tested donor. KIR genotyping did not delay transplantation. The time from search to transplant was identical for transplants using a KIR-genotyped versus a non–KIR-genotyped donor. Prospective evaluation can rapidly identify KIR favorable genotype donors, but choosing more donors per search would substantially increase the likelihood of having a KIR best or better donor available for transplantation. Transplant centers and donor registries must both commit extra effort to incorporate new characteristics (beyond HLA, age, and parity) into improved donor selection. Deliberate efforts to present additional genetic factors for donor selection will require novel procedures.     

Faecal microbiota transplantation: from practice to legislation before considering industrialization

Recurrent Clostridium difficile infections constitute an important medical concern. Evidence has been provided showing that faecal microbiota transplantation is a more efficient treatment than antibiotics. Serious side effects are unusual, and acceptability is not an obstacle. Nevertheless, protocols are heterogeneous with respect to the selection of donors and the methodology used for the faecal transplantation. Regulations by both the Food and Drug Administration and the French authorities consider stool samples to be drugs, and suggest strict supervision in clinical trials. Donor screening by questionnaire or by blood and stool analysis, which is essential in eliminating pathogens or viruses before transplantation, is similar in different countries, with a few exceptions. The traceability of the faecal transplant and long-term follow-up of the patients in clinical trials are issues that may be difficult to organize. The use of frozen microbiota facilitates transplantation, and the nasogastric route seems to be at least as effective as other invasive methods and avoids the risk of anaesthesia. Synthetic microbiota is an approach that selects a mixture of bacteria, thereby eliminating the risk of transmissible disease; however, this approach is not yet evidence-based. The use of pills, which is currently being tested in clinical trials, will certainly be the starting point for the extensive use and wide industrialization of faecal microbiota transplantation.     

Terapia celowana i transplantacja komórek krwiotwórczych szansą na wyleczenie chorych z ostrą białaczką szpikową

Acute myeloid leukemia (AML) is a heterogeneous disorder with a diverse prognosis. About 70% of AML patients may achieve complete remission after conventional chemotherapy, but long-term outcome remains unsatisfactory. The development of molecular biology resulted in a better understanding of AML pathogenesis as well as it allowed us the introduction of targeted therapy. However, most AML patients still require the allogeneic hematopoietic stem cell transplantation (alloHSCT) to be cured. The long-term results of alloHSCT for AML depend on a variety of factors including the age at transplant, the presence of well-defined risk factors and disease status at transplant. It seems that the combination of targeted therapy with conventional chemotherapy and subsequent alloHSCT may be a chance for curing a significant proportion of AML patients.     

Acute myeloid leukaemia: recent advances in therapy

Over the past ten years, there have been substantial advances in the treatment of AML. Intensive induction chemotherapy using seven-day courses of cytarabine and daunorubicin or amsacrine produce remission in 60-85% of patients. Median remission duration is 9-16 months. In some series, 20-40% of patients are in continuous remission for two years or more; many of these patients remain in remission for five years or longer and some may be cured. Bone marrow transplantation has evolved as a useful therapeutic modality capable of achieving long-term survival in some circumstances in which chemotherapy is relatively ineffective. Its precise role in the initial therapy of AML remains to be defined but it is likely to be beneficial in selected patients. These data indicate substantial recent progress in the treatment of this disease which was almost uniformly fatal 30 years ago. The fact that most patients relapse within 1-2 years reflects a lack of progress in developing effective postremission therapy. Maintenance chemotherapy, immunotherapy and CNS prophylaxis have little role in AML. It is unclear whether consolidation or intensification extend remissions or increase the proportion of long-term survivors; controlled randomized trials should answer this question within the next few years. Future progress in the treatment of AML awaits the development of more sensitive methods for detecting residual leukaemia, more effective use of current therapeutic modalities and the introduction of new effective drugs. Most data suggest that early intensive treatment is of key importance for achieving cures. We cannot presently distinguish, however, between patients cured by initial treatment and those who require further chemotherapy.