Reduced-intensity conditioning hematopoietic stem cell transplantation in patients over 60 years: hematologic malignancy outcomes are not impaired in advanced age

Reduced-toxicity conditioning regimen with low dose post-transplantation cyclophosphamide and low-dose anti-thymocyte globulin as graft-versus-host disease prophylaxis for haploidentical stem cell transplantation in older patients

Reduced-toxicity conditioning (RIC) regimens are used for allogeneic hematopoietic stem cell transplantation in older patients. However, successful outcomes are hindered by graft-versus-host disease (GVHD), treatment-related mortality, and relapse, particularly after haploidentical donor hematopoietic stem cell transplantation (HID-HSCT). The aim of this study was to evaluate the effectiveness of an RIC conditioning regimen that included a combination of cyclosporin A, methotrexate (on day + 1), mycophenolate, lower doses of post-transplantation PTCy (40 mg/kg on day + 3), and ATG (7.5 mg/kg) as GVHD prophylaxis prior to haplo-stem cell transplantation (haplo-SCT) in older patients.

METHODS

We retrospectively analyzed outcomes in 55 patients ≥ 55 years of age with hematologic malignancies treated with fludarabine, cytarabine, busulfan, and low-dose cyclophosphamide as the conditioning regimen between January 1, 2019, and November 30, 2023.

RESULTS

Neutrophil engraftment was successful in all patients within 28 days, with 54 patients (98.2%) achieving complete donor chimerism. The cumulative incidence of non-relapse mortality was 0% at 30 days, 7.5% at 100 days, and 19% at 1 year. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was 25% (95%CI, 15-38%), whereas that of grade III-IV aGVHD was 9.1% (95% CI, 3.3-19%). The cumulative incidence of extensive chronic graft-versus-host disease at 1 year was 3.6% (95%CI, 0.66-11%). The cumulative incidences of relapse, overall survival, and GVHD-free/relapse-free survival at 1 year were 9.0%, 71.6%, and 67.1%, respectively.

CONCLUSIONS

An RIC conditioning regimen, including a combination of lower PTCy/ATG as GVHD prophylaxis, followed by haplo-SCT, might be a promising option for appropriately selected older patients.

Myeloablative Dose of Busulfan and Fludarabine Combined with In Vivo T Cell Depletion Is Safe and Effective Conditioning for Acute Myeloid Leukemia and Myelodysplastic Syndrome Patients

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative strategy for acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). The prediction of transplantation-related mortality (TRM) using the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) score and an arbitrary upper age limit of 55 years for administering myeloablative conditioning (MAC) are common strategies to ensure a safe procedure. The use of reduced-toxicity conditioning regimens is an additional approach to providing safe and effective myeloablation. Herein we report the outcome of AML and MDS patients conditioned with fludarabine and a myeloablative dose of busulfan (FB4) stratified by age and HCT-CI score. The primary objective was overall survival (OS) for patients age ≥55 years. Secondary objectives were total OS, TRM, graft-versus-host disease (GVHD), and GVHD, relapse-free survival (GRFS). The 2 year OS was 72% in patients age <55 and 51% in patients age ≥55. In patients age ≥55 with an HCT-CI <2, the estimated 2 year OS was 64%, with median OS not reached. In those with HCT-CI ≥2, the 2-year OS was 43%, with a median OS of 14 months. The total cumulative incidence of relapse was 30% regardless of age or HCT-CI score. FB4 conditioning regimen offers a high rate of prolonged remission with a relapse rate similar to that reported in previous studies. These positive outcomes suggest that this conditioning platform can be offered to patients age ≥55 years in the absence of comorbidities, and that age should not be the sole determinant of conditioning intensity.

Allogeneic hematopoietic stem cell transplantation remains a feasible approach for elderly with acute myeloid leukemia: a 10-year experience

The incidence of AML increases with age. The implementation of reduced intensity conditioning and progress in supportive care enabled to perform allo-HSCT in elderly patients. The main objective of the study was to assess the safety and efficacy of allotransplantation in elderly AML.Forty nine patients (33 males) at median age of 68 years were identified. Data on patients' and transplant's related variables were retrieved from our local transplant registry. Most patients (65%) were transplanted from 10/10-HLA or 9/10-HLA matched unrelated donor, seven patients (14%) received stem cells from matched related donor and ten patients (20%) from haploidentical donor. All patients received reduced-intensity conditioning (RIC). Peripheral blood was a source of stem cells in all patients except one (98%). Acute GVHD developed in 22 patients (44%) with 5 individuals presenting grade III-IV. CMV reactivation was demonstrated in 19 patients (39%) till day + 100. In total, 22 patients (45%) have died. The main causes of death included infectious complications (n = 9), relapse with subsequent chemotherapy resistance (n = 7), steroid-resistant GvHD (n = 4) and other causes (n = 2). Twenty-seven patients (55%) were alive at the last contact, presented full donor chimerism and remained in the complete remission. The probability of OS and relapse-free survival (RFS) were 57% and 81% at 2 years, respectively. Older donor age showed negative impact on relapse. CMV reactivation, the severity of acute graft versus host disease and older donor age negatively influenced survival. Allo-HSCT remains a safe, feasible and effective procedure for elderly AML patients.

Cardiovascular disease and its management in children and adults undergoing hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for many malignancies, hemoglobinopathies, metabolic diseases, bone marrow failure syndromes, and primary immune deficiencies. Despite the significant improvement in survival afforded by HSCT, the therapy is associated with major short and long-term morbidity and mortality. Cardiovascular complications such as cardiomyopathy, arrhythmias, pulmonary hypertension, and pericardial effusions are increasingly recognized as potential outcomes following HSCT. The incidence of cardiac complications is related to various factors such as age, co-morbid medical conditions, whether patients received cardiotoxic chemotherapy prior to HSCT, the type of HSCT (autologous versus allogeneic), and the specific conditioning regimen. Thus, the cardiovascular evaluation has become a core component of the pre-transplant assessment, however, the practice differs from center to center as national guidelines and contemporary high-quality studies are lacking. We review the incidence of cardiotoxicity in pediatric and adult HSCT, potential mechanisms of injury, and effects on long-term outcomes. We also discuss the possible therapeutic approaches when disease arises, as well as the indications and need for surveillance before, during, and after transplantation.

Single cord blood transplantation for acute myeloid leukemia patients aged 60 years or older: a retrospective study in Japan

The availability of alternative donor sources could allow elderly patients to receive allogeneic hematopoietic cell transplantation (HCT). We retrospectively evaluated the outcomes of single-unit cord blood transplantation (CBT) in 1577 patients aged ≥60 years with acute myeloid leukemia (AML) in Japan between 2002 and 2017. In total, 990 (63%) patients were not in complete remission (CR) at the time of CBT. A myeloablative conditioning regimen (52%) and calcineurin inhibitor (CI) + mycophenolate mofetil (MMF)-based graft-versus-host disease (GVHD) prophylaxis (45%) were more commonly used. With a median follow-up for survivors of 31 months, the probability of overall survival and the cumulative incidence of leukemia-related mortality at 3 years was 31% and 29%, respectively. The cumulative incidence of non-relapse mortality (NRM) at 100 days and 3 years were 24% and 41%, respectively. The cumulative incidences of grade II-IV and grade III-IV acute GVHD at 100 days and extensive chronic GVHD at 2 years were 44%, 16%, and 14%, respectively. The cumulative incidence of neutrophil engraftment was 80% at 42 days. Results of multivariate analysis indicated that the following factors were significantly associated with higher overall mortality: performance status ≥1, hematopoietic cell transplantation-specific comorbidity index ≥3, adverse cytogenetics, extramedullary disease at diagnosis, and non-CR status at CBT. By contrast, female sex, HLA disparities ≥2, mycophenolate mofetil-based GVHD prophylaxis, and recent CBT were significantly associated with lower overall mortality. In conclusion, single CBT offers a curative option for AML patients aged ≥60 years with careful patient selection.

Outcomes of Allogeneic Stem Cell Transplant for Elderly Patients with Hematologic Malignancies

Reduced-intensity conditioning (RIC) regimens, improved HLA matching, and better supportive care allow allogeneic stem cell transplant (alloSCT) to be offered to older patients. Only a small percentage of eligible patients between ages 65 and 74 years actually undergo alloSCT, and comprehensive outcome data from the aging population are still lacking. We examined the outcome of older patients who underwent alloSCT using melphalan-based RIC for hematologic malignancies at our institution. We identified 125 patients older than 65 years (median, 69; range, 66 to 77) who underwent matched related donor, matched unrelated donor, or combined haploidentical/umbilical cord alloSCT between 2012 through November, 2017. Among them, 52 (41.6%) and 70 (56%) had, respectively, intermediate and high/very high Center for International Blood and Marrow Transplant Research (CIBMTR) disease risk index (DRI). One hundred six patients (85%) received fludarabine/melphalan-based RIC regimen with either antithymocyte globulin (ATG) or alemtuzumab. The median time to neutrophil engraftment was 13 days (range, 8 to 37) and platelet engraftment 17 days (range, 9 to 169). The cumulative incidence of nonrelapse mortality was 11.5% at 100 days and 30.1% and 34.8% at 1 and 2 years, respectively. The cumulative incidence of relapse was 35% and 40% at 1 and 2 years. The cumulative incidence of grades II to IV acute graft-versus-host disease (GVHD) at day 100 and 6 months was 29.5% and 34.5%, and chronic GVHD at 6, 12, and 24 months was 2.5%, 5.2%, and 6.3%, respectively. With a median follow-up of 32 months, the 1-, 2-, and 3-year progression-free survival (PFS) was 34.6%, 24.4%, and 16.5%, respectively. The graft GVHD-free survival was 24.6%, 16.1%, and 9.3%, respectively. The 1-, 2-, and 3-year overall survival (OS) was 44.5%, 30.7%, and 26.5%, respectively. In multivariable analysis, low albumin was predictive of poor PFS and OS and high hematopoietic cell transplantation-specific comorbidity index, and CIBMTR DRI was predictive of worse graft GVHD-free survival. Among long-term survivors the median Karnofsky performance status was 80. Older patients, even when referred with advanced disease, can benefit from melphalan-based alloSCT with HLA-matched or alternative donor sources without discernible impact of donor source on outcome. Using alemtuzumab- or ATG-based in vivo T cell depletion, the incidence of chronic GVHD is extremely low. Performance status in survivors is excellent. Better predictors for outcome in this patient population need to be identified.

Allogeneic hematopoietic cell transplantation compared to chemotherapy consolidation in older acute myeloid leukemia (AML) patients 60-75 years in first complete remission (CR1): an alliance (A151509), SWOG, ECOG-ACRIN, and CIBMTR study

The preferred post-remission therapy for older patients with acute myeloid leukemia (AML) in first complete remission (CR1) remains uncertain. In this retrospective, multicenter study, we compared the outcomes for older AML patients (age 60-77 years) receiving allogeneic hematopoietic cell transplantation (alloHCT) (n = 431) with those treated on prospective National Clinical Trials Network induction and nontransplantation chemotherapy (CT) consolidation trials (n = 211). AlloHCT patients were younger (median age: 64.2 versus 67.9 years, p < 0.001), but more frequently had high-risk AML (high WBC, secondary AML, and unfavorable cytogenetics). Overall survival (OS) was worse in alloHCT during the first 9 months after CR1 (HR = 1.52, p = 0.02), but was significantly better thereafter (HR = 0.53, p < 0.0001) relative to CT. Treatment-related mortality (TRM) following HCT was worse in the first 9 months (HR = 2.8, 95% CI: 1.5-5.2, p = 0.0009), while post-HCT relapse was significantly less frequent beyond 9 months (HR = 0.42, 95% CI: 0.29-0.61, p < 0.0001). Despite higher early TRM, alloHCT recipients had superior long-term OS [29% (24-34%) versus CT 13.8% (9-21%) at 5 years]. Although this is a retrospective analysis with potential biases, it indicates that alloHCT led to heightened early risks from TRM, yet reduced relapse and superior long-term survival relative to CT in older AML patients in CR1.

Reimbursement, Utilization, and 1-Year Survival Post-Allogeneic Transplantation for Medicare Beneficiaries With Acute Myeloid Leukemia

Background

The economics of allogeneic hematopoietic cell transplantation (alloHCT) for older patients with acute myeloid leukemia (AML) affects clinical practice and public policy. To assess reimbursement, utilization, and overall survival (OS) up to 1 year post-alloHCT for Medicare beneficiaries aged 65 years or older with AML, a unique merged dataset of Medicare claims and national alloHCT registry data was analyzed.

Methods

Patients diagnosed with AML undergoing alloHCT from 2010 to 2011 were included for a retrospective cohort analysis with generalized linear model adjustment. One-year post-alloHCT reimbursement included Medicare, secondary payer, and beneficiary copayments (no coinsurance) (inflation adjusted to 2017 dollars). Cost-to-charge ratios were applied to estimate department-specific inpatient costs. Cox proportional hazards regression models were utilized to identify risk factors of 1-year OS post-alloHCT.

Results

A total of 250 patients met inclusion criteria. Mean total reimbursement was $230 815 (95% confidence interval [CI] = $214 381 to $247 249) 1 year after alloHCT. Pharmacy was the most- costly inpatient service category. Adjusted mean total reimbursement was statistically higher for patients who received cord blood grafts (P = .01), myeloablative conditioning (P < .0001), and alloHCT in the Northeast and West (P = .03). Mortality increased with age (hazard ratio [HR] = 1.08, 95% CI = 1.0 to 1.17), poorer Karnofsky performance score (<90% vs ≥90%, HR = 1.60, 95% CI = 1.08 to 2.35), and receipt of myeloablative conditioning (HR = 1.88, 95% CI = 1.21 to 2.92).

Conclusions

This merged dataset allowed adjustment for a richer set of patient- and HCT-related characteristics than claims data alone. The finding that nonmyeloablative conditioning was associated with lower reimbursement and improved OS 1 year post-alloHCT warrants further investigation.

Hematopoietic Cell Transplant (HCT) in the Elderly: Myths, Controversies and Unknowns

The incidence of most hematological malignancies increases with age. Despite the higher incidence of hematological malignancies in the elderly, the geriatric population is poorly represented in the early oncology clinical trials that established the current standards of care. Hematopoietic cell transplant (HCT), either upfront or at relapse, provides a potentially life-prolonging, often curative option for many patients with hematological malignancies and is considered the standard of care, at least for younger patients. Historically, the concern that older adults undergoing HCT may experience higher morbidity and transplant-related complications has limited the use of this potentially curative option to younger adults, particularly in allogeneic (allo-) HCT. There is growing evidence to support the feasibility, tolerability, and relatively similar effectiveness of both autologous and allo-HCT in the geriatric population. In the allo-HCT setting, nonmyeloablative/reduced-intensity conditioning (NMA/RIC) has expanded the spectrum of patients that can be considered for this approach. Overall survival is largely affected by disease stage, performance status, and comorbidities rather than by chronological age per se. Comprehensive geriatric assessment (CGA) is a promising tool that can uncover frequently undocumented vulnerabilities in an elderly transplant-eligible patient. Serial study of CGA throughout the peri-HCT period may help predict the short- and long-term impact of HCT on an older adult's functional status and quality of life. Further research is needed to evaluate whether early intervention to improve such vulnerabilities can improve survival and quality of life of these older patients.

Bridging Strategies to Allogeneic Transplant for Older AML Patients

Treatment options for older patients with intermediate or high-risk acute myeloid leukemia (AML) remain unsatisfactory. Allogeneic stem cell transplantation, the treatment of choice for the majority of younger AML patients, has been hampered in elderly patients by higher treatment related mortality, comorbidities and lack of a suitable donor. With the higher availability of suitable donors as well as of reduced intensity conditioning regimens, novel low intensity treatments prior to transplantation and optimized supportive care, the number of older AML patients being successfully transplanted is steadily increasing. Against this background, we review current treatment strategies for older AML patients planned for allogeneic stem cell transplantation based on clinical trial data, discussing differences between approaches with advantages and pitfalls of each. We summarize pre-treatment considerations that need to be taken into account in this highly heterogeneous older population. Finally, we offer an outlook on areas of ongoing clinical research, including novel immunotherapeutic approaches that may improve access to curative therapies for a larger number of older AML patients.

Socioeconomic and health system factors associated with lower utilization of hematopoietic cell transplantation in older patients with acute myeloid leukemia

Receipt of hematopoietic cell transplantation (HCT) can improve overall survival in older patients with intermediate or high-risk acute myeloid leukemia (AML); however, utilization of HCT is poor. It is important to understand the factors that affect the receipt of HCT in a real-world setting among the older patients. We utilized the National Cancer Database to determine receipt of HCT in older patients (61-75 years) with intermediate or high-risk AML reported between 2003 and 2012. Multivariate logistic regression analysis was used to determine factors associated with receipt of HCT. Only 5.5% of older patients (n = 17,555) underwent HCT. Factors associated with a lower likelihood of receiving HCT included receipt of care in a non-academic hospital, race other than white, older age, Charlson comorbidity score of ≥1, uninsured status, Medicaid or Medicare insurance, and lower educational status. The receipt of HCT in older patients is low and varies based on biological as well as non-biologic factors, such as hospital type, insurance, and educational status. Nationwide efforts to improve access to HCT for appropriate patients are necessary.

Frailty: the missing piece of the pre- hematopoietic cell transplantation assessment?

Hematopoietic stem cell transplantation (HSCT) represents a curative option for those afflicted with numerous hematologic malignancies and bone marrow failure syndromes. Advances and refinement of the HSCT process have resulted in increasing number of transplants performed on older patients in the recent years. Pre-transplant assessments (PTA) function to risk stratify patients prior to undergoing HSCT in an effort to predict those at higher risk of treatment-related toxicity, to inform risk/benefit assessments and to aid clinical decision making. Traditionally used risk stratification parameters such as chronologic age, comorbidity and performance status may not fully capture physical function, physiologic fitness, highlighting a need for improvement in PTA. Incorporation of frailty measurements in pre-HSCT assessments, particularly in elderly transplant candidates, may result in improving predictive ability of existing tools such as the Hematopoietic Cell Transplantation Comorbidity Index and Karnofsky performance status. Here, we review existing pre-HSCT assessment tools, measures of frailty that may aid in risk stratification for patients undergoing HSCT and directions for future research using frailty in the pre-HSCT setting.

Impact of Allogeneic Stem Cell Transplantation in First Complete Remission in Acute Myeloid Leukemia: A National Population-Based Cohort Study

To examine the outcomes of allogeneic stem cell transplantation (HSCT) in first complete remission (CR1) compared with chemotherapy alone in a population-based setting, we identified a cohort of patients with acute myeloid leukemia (AML) aged 15 to 70 years diagnosed between 2000 and 2014 in Denmark. Using the Danish National Acute Leukemia Registry, we compared relapse risk, relapse-free survival (RFS), and overall survival (OS) between patients with unfavorable cytogenetic features receiving postremission therapy with conventional chemotherapy only versus those undergoing HSCT in CR1. To minimize immortal time bias, we performed Cox proportional hazards regression, included date of allogeneic HSCT as a time-dependent covariate, and stratified the results by age (<60 or ≥60 years) and cytogenetic risk group. Overall, 1031 patients achieved a CR1. Of these, 196 patients (19%) underwent HSCT. HSCT was associated with a lower relapse rate (24% versus 49%) despite a similar median time to relapse (287 days versus 265 days). In all subgroups, the risk of relapse was lower and both RFS and OS were superior in recipients of HSCT (OS, adjusted mortality ratios: all patients, .54 [95% confidence interval (CI), .42-.71]; patients age <60 years, .58 [95% CI, .42-.81]; patients age ≥60 years, .42 [95% CI, .26-.69]; patients with intermediate-risk cytogenetics, .63 [95% CI, .43-.87]; patients with adverse-risk cytogenetics, .40 [95% CI, .24-.67]). In conclusion, in this population-based nationwide cohort study, HSCT was associated with improved survival in both younger and older patients and in patients with both intermediate and adverse cytogenetic risk.

T Cell Depletion as an Alternative Approach for Patients 55 Years or Older Undergoing Allogeneic Stem Cell Transplantation as Curative Therapy for Hematologic Malignancies

T cell-depleted (TCD) allogeneic hematopoietic stem cell transplantation (HSCT) is curative treatment for hematologic malignancies in adults, shown to reduce graft-versus-host disease (GVHD) without increased relapse. We retrospectively reviewed a single-center, 11-year experience of 214 patients aged ≥ 55 years to determine tolerability and efficacy in the older adult. Most patients (70%) had myeloid diseases, and most acute leukemias were in remission. Median age was 61 years, with related and unrelated donors ≥8/10 HLA matched. Hematopoietic cell transplantation-specific comorbidity index scores were intermediate and high for 84%. Conditioning regimens were all myeloablative. Grafts were peripheral blood stem cells (97%) containing CD3 dose ≤103-4/kg body weight, without pharmacologic GVHD prophylaxis. With median follow-up of 70 months among survivors, Kaplan-Meier estimates of overall and relapse-free survival were 44% and 41%, respectively (4 years). Cumulative incidence of nonrelapse mortality at day +100 was only 10%. Incidence of GVHD for acute (grades II to IV) was 9% at day +100 and for chronic was 7% at 2 and 4 years (8 extensive, 1 overlap). Median Karnofsky performance status for patients > 2 years post-transplant was 90%. As 1 of the largest reports for patients ≥2 aged ≥55 years receiving TCD HSCTs, it demonstrates curative therapy with minimal GVHD, similar to that observed in a younger population.

Age does not adversely influence outcomes among patients older than 60 years who undergo allogeneic hematopoietic stem cell transplant for AML and myelodysplastic syndrome

Allogeneic hematopoietic stem cell transplant (AHSCT) outcomes data of older AML/myelodysplastic syndrome (MDS) patients are limited. We retrospectively evaluated consecutive patients ⩾60 years old with AML/MDS who underwent AHSCT between January 2005 and December 2014. The primary objectives were to determine nonrelapse mortality (NRM), relapse, relapse-free survival (RFS) and overall survival (OS) at 1 year post AHSCT. A total of 159 patients underwent AHSCT with a median age of 64 (range, 60-75) years. Of these, 103 patients (65%) had AML and 56 patients (35%) had MDS. At 1 year post AHSCT, grade III-IV acute GvHD and chronic GvHD occurred in 20.8% (95% confidence interval (CI), 14.9-27.5%) and 54.1% (95% CI, 46.0-61.5%) of patients, respectively. NRM, RFS, relapse rate and OS at 1 year post AHSCT were 25.3% (95% CI, 18.8-32.3%), 53.3% (95% CI, 46.1-61.7%), 21.4% (95% CI, 15.4-28.1%) and 56.4% (95% CI, 49.2-54.7%), respectively. High disease risk index was associated with poor RFS, OS and higher relapse rate (P<0.03), whereas non-thymoglobulin-based GvHD prophylaxis, higher comorbidity index (⩾3) and MDS were associated with higher NRM (P<0.03). Importantly, age did not have an adverse effect on NRM, relapse, RFS and OS. AHSCT was well tolerated. Hence, older age alone should not be considered a contraindication to AHSCT.

The who, how and why: Allogeneic transplant for acute myeloid leukemia in patients older than 60years

Acute myelogenous leukemia (AML) is primarily a disease of the elderly, and as such, our approach to treatment needs to be tailored to address an aging population. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only potentially curative treatment for intermediate and high risk AML, and until recently, its use had been limited to a younger population and dependent on availability of a donor. Advances in conditioning regimens, supportive care, and the use of alternative donor sources have greatly expanded access to this therapy. In this review, we summarize the challenges and unique biological aspects of treatment with allogeneic stem cell transplantation in this group of patients older than 60years. We also highlight areas of ongoing research including measurement of residual disease prior to and following transplant, post-remission maintenance therapy, and natural killer cell immunotherapy. Finally, we propose future directions for AML treatment in an elderly and aging population.

Healthcare Costs and Utilization for Patients Age 50 to 64 Years with Acute Myeloid Leukemia Treated with Chemotherapy or with Chemotherapy and Allogeneic Hematopoietic Cell Transplantation

The primary aim of this study was to describe healthcare costs and utilization during the first year after a diagnosis of acute myeloid leukemia (AML) for privately insured non-Medicare patients in the United States aged 50 to 64 years who were treated with either chemotherapy or chemotherapy and allogeneic hematopoietic cell transplantation (alloHCT). MarketScan (Truven Health Analytics) adjudicated total payments for inpatient, outpatient, and prescription drug claims from 2007 to 2011 were used to estimate costs from the health system perspective. Stabilized inverse propensity score weights were constructed using logistic regression to account for differential selection of alloHCT over chemotherapy. Weighted generalized linear models adjusted costs and utilization (hospitalizations, inpatient days, and outpatient visit-days) for differences in age, sex, diagnosis year, region, insurance plan type, Elixhauser Comorbidity Index), and 60-day prediagnosis costs. Because mortality data were not available, models could not be adjusted for survival times. Among 29,915 patients with a primary diagnosis of AML, 985 patients met inclusion criteria (774 [79%] receiving chemotherapy alone and 211 [21%] alloHCT). Adjusted mean 1-year costs were $280,788 for chemotherapy and $544,178 for alloHCT. Patients receiving chemotherapy alone had a mean of 4 hospitalizations, 52.9 inpatient days, and 52.4 outpatient visits in the year after AML diagnosis; patients receiving alloHCT had 5 hospitalizations, 92.5 inpatient days, and 74.5 outpatient visits. Treating AML in the first year after diagnosis incurs substantial healthcare costs and utilization with chemotherapy alone and with alloHCT. Our analysis informs healthcare providers, policymakers, and payers so they can better understand treatment costs and utilization for privately insured patients aged 50 to 64 with AML.

Cytogenetic risk determines outcomes after allogeneic transplantation in older patients with acute myeloid leukemia in their second complete remission: A Center for International Blood and Marrow Transplant Research cohort analysis

BACKGROUND

Allogeneic hematopoietic cell transplantation (HCT) offers curative potential to a number of older patients with acute myeloid leukemia (AML) in their first complete remission. However, there are limited data in the literature concerning post-HCT outcomes for older patients in their second complete remission (CR2).

METHODS

The purpose of the current study was to retrospectively investigate within the Center for International Blood and Marrow Transplant Research database parameters influencing posttransplant outcomes for patients 60 years of age or older undergoing HCT for AML in CR2.

RESULTS

In total, 196 patients from 78 centers were identified; the median age was 64 years (range, 60-78 years). Seventy-one percent had a Karnofsky performance status ≥ 90 at the time of HCT. Reduced-intensity conditioning regimens were used in 159 patients (81%). A univariate analysis demonstrated a 3-year overall survival (OS) rate of 42% (95% confidence interval [CI], 35%-49%), a leukemia-free survival rate of 37% (95% CI, 30%-44%), a cumulative incidence of nonrelapse mortality of 25% (95% CI, 19%-32%), and a cumulative incidence of relapse (CIR) of 38% (95% CI, 31%-45%). A multivariate analysis demonstrated that cytogenetic risk was the only independent risk factor for OS (P = .023) with a hazard ratio (HR) of 1.14 (95% CI, 0.59-2.19) for intermediate-risk cytogenetics and an HR of 2.32 (95% CI, 1.05-5.14) for unfavorable-risk cytogenetics. For CIR, cytogenetic risk was also the only independent prognostic factor (P = .01) with an HR of 1.10 (95% CI, 0.47-2.56) for intermediate-risk cytogenetics and an HR of 2.98 (95% CI, 1.11-8.00) for unfavorable-risk cytogenetics.

CONCLUSIONS

Allogeneic HCT is a curative treatment option for older patients with AML in CR2, particularly for those with favorable or intermediate cytogenetic risk. Cancer 2017;123:2035-2042. © 2017 American Cancer Society.

CD25 as an adverse prognostic factor in elderly patients with acute myeloid leukemia

OBJECTIVES

CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated.

METHODS

We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry.

RESULTS

CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm.

DISCUSSION

An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients.

CONCLUSION

CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.

Impact of age on outcomes of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in elderly patients with acute myeloid leukemia

Previous studies have repeatedly reported that increasing age is a significant risk factor for worse outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT) among patients with acute myeloid leukemia (AML). However, more recent studies reported conflicting results regarding the association between age and outcomes in elderly patients. Therefore, we conducted a large-scale, nationwide retrospective study to examine the impact of age on outcomes of allo-HSCT with reduced intensity conditioning (RIC) for AML patients who were older than 50 years. Of the 757 patients, 89 patients (11.8%) were 50-54, 249 patients (32.9%) were 55-59, 301 patients (39.8%) were 60-64 and 118 patients (15.6%) were ≥65 years old. The 3-year overall survival (OS) (47.8, 45.2, 37.9, and 36.6% for patients aged 50-54, 55-59, 60-64, and ≥65 years, respectively, P = 0.24) and nonrelapse mortality (NRM) (24.0, 22.8, 29.2, and 27.6% for patients aged 50-54, 55-59, 60-64, and ≥65 years, respectively, P = 0.49) were not significantly different among the four age groups. Multivariate analysis revealed that increased age had no significant effect on OS or NRM after adjusting for covariates. These results suggested that advanced patient age is not a contraindication for RIC allo-HSCT in elderly AML patients.

Phase II Study of Allogeneic Transplantation for Older Patients With Acute Myeloid Leukemia in First Complete Remission Using a Reduced-Intensity Conditioning Regimen: Results From Cancer and Leukemia Group B 100103 (Alliance for Clinical Trials in Oncology)/Blood and Marrow Transplant Clinical Trial Network 0502

PURPOSE

Long-term survival rates for older patients with newly diagnosed acute myeloid leukemia (AML) are extremely low. Previous observational studies suggest that allogeneic hematopoietic stem-cell transplantation (HSCT) may improve overall survival (OS) because of lower rates of relapse. We sought to prospectively determine the value of HSCT for older patients with AML in first complete remission.

PATIENTS AND METHODS

We conducted a prospective multicenter phase II study to assess the efficacy of reduced-intensity conditioning HSCT for patients between the ages of 60 and 74 years with AML in first complete remission. The primary end point was disease-free survival at 2 years after HSCT. Secondary end points included nonrelapse mortality (NRM), graft-versus-host disease (GVHD), relapse, and OS.

RESULTS

In all, 114 patients with a median age of 65 years received transplantations. The majority (52%) received transplantations from unrelated donors and were given antithymocyte globulin for GVHD prophylaxis. Disease-free survival and OS at 2 years after transplantation were 42% (95% CI, 33% to 52%) and 48% (95% CI, 39% to 58%), respectively, for the entire group and 40% (95% CI, 29% to 55%) and 50% (95% CI, 38% to 64%) for the unrelated donor group. NRM at 2 years was 15% (95% CI, 8% to 21%). Grade 2 to 4 acute GVHD occurred in 9.6% (95% CI, 4% to 15%) of patients, and chronic GVHD occurred in 28% (95% CI, 19% to 36%) of patients. The cumulative incidence of relapse at 2 years was 44% (95% CI, 35% to 53%).

CONCLUSION

Reduced-intensity conditioning HSCT to maintain remission in selected older patients with AML is relatively well tolerated and appears to provide superior outcomes when compared with historical patients treated without HSCT. GVHD and NRM rates were lower than expected. Future transplantation studies in these patients should focus on further reducing the risk of relapse.

Advances in the treatment of elderly and frail patients with acute myeloid leukemia

PURPOSE OF REVIEW

Significant advances have been made in the treatment of younger patients with acute myeloid leukemia over the past 3 decades, but prognosis in the elderly has remained dismal, with median survival times of only a few months. Although a small percentage of older patients may be cured by standard chemotherapy, it is clear that several aspects of frontline management require improvement and novel approaches are urgently needed. This review focuses on treatment options currently available to older patients with acute myeloid leukemia, with an emphasis on new therapeutics.

RECENT FINDINGS

Developing risk-assessment tools is critical to identify older patients who are most likely to benefit from intensive chemotherapy, but optimal induction and postremission therapies have yet to be determined in this population. New strategies and treatments are emerging and under current assessment. In particular, investigations of monoclonal antibodies, hypomethylating agents, signal transduction inhibitors, and novel cytotoxics hold promise for improving outcomes in older patients with acute myeloid leukemia, including those for whom traditional chemotherapy is not considered appropriate.

SUMMARY

Acute myeloid leukemia remains a therapeutic challenge in elderly patients, but, following a period of paucity in discoveries, several new treatments are finally emerging that may offer future improvement for these patients.

Impact of pre-transplant co-morbidities on outcome after alemtuzumab-based reduced intensity conditioning allo-SCT in elderly patients: a British Society of Blood and Marrow Transplantation study

The advent of reduced intensity conditioning (RIC) regimens has permitted the extension of allo-SCT to selected patients into their eighth decade but GVHD remains a major cause of morbidity and mortality. Alemtuzumab is increasingly used to reduce the risk of severe GVHD, but there are concerns that T-cell depletion may compromise outcome particularly in older patients. We therefore studied the impact of pre-transplant factors on the outcome of 187 patients with a haematological malignancy over the age of 60 transplanted using an alemtuzumab-based RIC regimen of whom co-morbidity scoring was possible in 169. Of the patients, 120 had a haematopoietic cell transplantation co-morbidity index (HCT-CI) of 0 or 1 and 49 had a score of 2 or more. The 5-year OS was 33%. In multivariable analysis, OS was determined by co-morbidity score (P=0.001) and disease status at transplant (P=0.004) but not by patient age. Non-relapse mortality was determined by co-morbidity score (P=0.001). Two-year OS for patients with a HCT-CI of 0-1 was 59 versus 6% for patients with a higher score. Alemtuzumab-based RIC allografts can be delivered safely in patients aged over 60 but co-morbidity scoring is mandatory to identify patients who will benefit.

Hematopoietic stem cell transplantation for hematologic malignancies in older adults: geriatric principles in the transplant clinic

Hematopoietic cell transplantation (HCT) provides a life-prolonging or potentially curative treatment option for patients with hematologic malignancies. Given the high transplant-related morbidity, these treatment strategies were initially restricted to younger patients, but are increasingly being used in older adults. The incidence of most hematologic malignancies increases with age; with the aging of the population, the number of potential older candidates for HCT increases. Autologous HCT (auto-HCT) in older patients may confer a slightly increased risk of specific toxicities (such as cardiac toxicities and mucositis) and have modestly lower effectiveness (in the case of lymphoma). However, auto-HCT remains a feasible, safe, and effective therapy for selected older adults with multiple myeloma and lymphoma. Similarly, allogeneic transplant (allo-HCT) is a potential therapeutic option for selected older adults, although fewer data exist on allo-HCT in older patients. Based on currently available data, age alone is not the best predictor of toxicity and outcomes; rather, the comorbidities and functional status of the older patient are likely better predictors of toxicity than chronologic age in both the autologous and allogeneic setting. A comprehensive geriatric assessment (CGA) in older adults being considered for either an auto-HCT or allo-HCT may identify additional problems or geriatric syndromes, which may not be detected during the standard pretransplant evaluation. Further research is needed to establish the utility of CGA in predicting toxicity and to evaluate the quality of survival in older adults undergoing HCT.

Quality of life and outcomes in patients⩾60 years of age after allogeneic hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) has become an established standard of care for many older patients with hematologic malignancies. The effect of transplantation on the quality of life (QOL) of older patients, however, has not been well studied. We thus analyzed QOL in patients ⩾60 undergoing an allogeneic HCT compared with patients <60 years. Prospective psychometric instruments were administered to 351 patients who underwent HCT from 2003 to 2010. Psychometric data were assessed longitudinally by validated questionnaires: Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT), Coping Inventory and the Profile of Mood State-Short Form. Patients ⩾60 reported better social (P=0.006) and functional well-being (P=0.05) with FACT assessment, and had better total scores, (P=0.043) across all time points. When adjusted for baseline QOL scores as a covariate, social well-being remained significantly better, whereas the other scores became non-significant. With a median follow-up of 49 months, there were no significant differences in OS, relapse-free survival, relapse or chronic GVHD. This study provides further evidence that advanced age should not be a barrier in the decision to pursue allogeneic HCT. Older patients achieved comparable QOL when compared with younger patients.

Alternative novel therapies for the treatment of elderly acute myeloid leukemia patients

With a median age at diagnosis of approximately 65-70 years, acute myeloid leukemia (AML) represents a major therapeutic challenge in the elderly. Only 30-35% of elderly patients with AML are considered eligible for intensive chemotherapy and do actually receive it. However, the long-term benefit associated with intensive chemotherapy remains marginal, and the overall outcome for this population remains poor. The remaining 60-65% of elderly AML patients receives supportive care only. Nevertheless, several studies have indicated that patients who receive any therapy had a better outcome if compared with patients who receive supportive care only. Thus, the development of novel, less toxic, targeted agents is offering new options to older AML patients who are unfit for intensive approaches. In the present review, we will report on the results achieved using intensive chemotherapy and novel agents, and will describe some of the new strategies under development for treating older AML patients.

Alternative donor transplantation for older patients with acute myeloid leukemia in first complete remission: a center for international blood and marrow transplant research-eurocord analysis

We studied patients with acute myeloid leukemia (AML) over age 50 and in first complete remission (CR1) after adult unrelated donor (URD) (n = 441, 8/8 HLA matched; n = 94, 7/8 HLA matched) or umbilical cord blood (UCB; n = 205) transplantations. UCB recipients achieved CR1 within 8 weeks less often, and received reduced-intensity conditioning and cyclosporine-based graft-versus-host disease (GVHD) prophylaxis more often. Neutrophil recovery was slower in UCB (69% by day 28) compared with 8/8 HLA-matched URD (97%) and 7/8 HLA-matched (91%) (P < .001) recipients. Three-year transplantation-related mortality (TRM) was higher and leukemia-free survival (LFS) lower with UCB (35% and 28%, respectively) versus 8/8 HLA-matched URD (27% and 39%, respectively). TRM was higher in 7/8 HLA-matched URD (41%, P = .01), but LFS was similar at 34% (P = .39). Three-year chronic GVHD was the lowest in UCB (28%) versus 53% and 59% in 8/8 and 7/8 HLA-matched URD recipients, respectively. Three-year survival was 43% in 8/8 HLA-matched URD (95% confidence interval [CI], 38% to 48%), 30% in UCB (95% CI, 23% to 37%) (P = .002) and 37% in 7/8 URD (95% CI, 27 to 46). Allotransplantation for AML in CR1 with any of these grafts extends LFS for over one third of older patients. In the absence of an 8/8 HLA-matched URD or when transplantation is needed urgently, UCB can provide extended survival. Less frequent chronic GVHD with UCB transplantation may be of particular value for older patients.

Should elderly patients with higher-risk myelodysplastic syndromes undergo allogeneic hematopoietic stem cell transplantation?

Myelodysplastic syndromes (MDS) include a group of hematopoietic malignancies characterized by dysplastic changes, ineffective hematopoiesis and variable risk of leukemic progression. At diagnosis, 86% of MDS patients are ≥60 years. Azacitidine, the only drug that prolongs life in high-risk (HR)-MDS patients, adds a median of only 9.5 months to life. Allogeneic stem cell transplantation (alloSCT) remains the only potentially curative approach. Despite recent improvements including use of reduced intensity conditioning (RIC) that decrease transplant-related mortality, alloSCT continues to be used rarely in elderly MDS. There is paucity of data regarding outcomes of RIC alloSCT in elderly MDS patients, especially in direct comparison with azanucleosides. In this paper, the authors discuss the recent Markov decision analysis by Koreth et al. in which investigators demonstrated superior survival of patients with HR-MDS aged 60-70 years who underwent RIC alloSCT in comparison with those who were treated with azanucleosides.

Emerging immunotherapies in older adults with acute myeloid leukemia

PURPOSE OF REVIEW

We summarize recent advances for acute myeloid leukemia (AML) in older patients, with a focus on immunotherapeutics. Although the recently updated US SEER data still show that the majority of older AML patients do not receive any therapy, this reality is slowly changing. Advances in our understanding of the biology of AML and in the field of immunology are facilitating the development of alternative therapeutic options for patients, affording more and novel opportunities for potentially curative treatment.

RECENT FINDINGS

Data from multiple cooperative groups show that older patients benefit from the incorporation of gemtuzumab ozogamicin, an anti-CD33 mAb toxin, into induction regimens. The first prospective study for reduced-intensity conditioning allogeneic hematopoietic stem cell transplantation in older AML patients was reported at the American Society of Hematology Annual Meeting, 2012; the approach was feasible and improved disease-free survival over conventional chemotherapy. Proof-of-concept trials targeting specific antigens such as WT1 or novel unique leukemia-associated antigens are currently underway, as well as other trials using chimeric antigen receptor T cells or (natural killer/effector cells in nontransplantation settings.

SUMMARY

Wider application of immunotherapies such as allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning have altered the landscape and offer potential for cure of an increasing number of older AML patients.

Role of reduced-intensity conditioning allogeneic hematopoietic stem-cell transplantation in older patients with de novo myelodysplastic syndromes: an international collaborative decision analysis

PURPOSE

Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders that are more common in patients aged ≥ 60 years and are incurable with conventional therapies. Reduced-intensity conditioning (RIC) allogeneic hematopoietic stem-cell transplantation is potentially curative but has additional mortality risk. We evaluated RIC transplantation versus nontransplantation therapies in older patients with MDS stratified by International Prognostic Scoring System (IPSS) risk.

PATIENTS AND METHODS

A Markov decision model with quality-of-life utility estimates for different MDS and transplantation states was assessed. Outcomes were life expectancy (LE) and quality-adjusted life expectancy (QALE). A total of 514 patients with de novo MDS aged 60 to 70 years were evaluated. Chronic myelomonocytic leukemia, isolated 5q- syndrome, unclassifiable, and therapy-related MDS were excluded. Transplantation using T-cell depletion or HLA-mismatched or umbilical cord donors was also excluded. RIC transplantation (n = 132) stratified by IPSS risk was compared with best supportive care for patients with nonanemic low/intermediate-1 IPSS (n = 123), hematopoietic growth factors for patients with anemic low/intermediate-1 IPSS (n = 94), and hypomethylating agents for patients with intermediate-2/high IPSS (n = 165).

RESULTS

For patients with low/intermediate-1 IPSS MDS, RIC transplantation LE was 38 months versus 77 months with nontransplantation approaches. QALE and sensitivity analysis did not favor RIC transplantation across plausible utility estimates. For intermediate-2/high IPSS MDS, RIC transplantation LE was 36 months versus 28 months for nontransplantation therapies. QALE and sensitivity analysis favored RIC transplantation across plausible utility estimates.

CONCLUSION

For patients with de novo MDS aged 60 to 70 years, favored treatments vary with IPSS risk. For low/intermediate-1 IPSS, nontransplantation approaches are preferred. For intermediate-2/high IPSS, RIC transplantation offers overall and quality-adjusted survival benefit.

Outcomes in patients age 70 or older undergoing allogeneic hematopoietic stem cell transplantation for hematologic malignancies

Allogeneic hematopoietic stem cell transplantation (HSCT) can achieve durable remissions in a number of patients with advanced hematologic malignancies. Little is known about the safety of HSCT in patients age 70 or older. Consecutive patients (n = 54) age 70 or older underwent HSCT between 2007 and 2012. Diseases included acute myelogenous leukemia (n = 25), myelodysplastic syndrome (n = 12), chronic lymphocytic leukemia (n = 5), non-Hodgkin lymphoma (n = 4), acute lymphoblastic leukemia (n = 3), myeloproliferative neoplasm (n = 4), and chronic myelogenous leukemia (n = 1). Median follow-up for survivors was 21 months. All patients received reduced-intensity conditioning regimens, primarily busulfan/fludarabine. All patients received unmanipulated peripheral blood stem cell grafts: 44 from 8/8 matched unrelated donors, 8 from matched related donors, and 2 from 7/8 matched unrelated donors. Graft-versus-host disease (GVHD) prophylaxis was calcineurin inhibitor-based in all patients. The median age at transplantation was 71 years (range, 70 to 76); the median HCT comorbidity index score was 1 (range, 0 to 5). Two patients died before hematopoietic recovery (1 with graft failure and 1 with disease progression), and 1 patient relapsed before hematopoietic recovery; otherwise, all engrafted with median donor chimerism of 94% at 1 month. Cumulative incidence of grades II to IV acute GVHD was 13% and of grades III to IV acute GVHD, 9.3%. At 2 years, the cumulative incidence of chronic GVHD was 36%, progression-free survival was 39%, overall survival was 39%, and relapse was 56%. Nonrelapse mortality was 3.7% at day +100 and 5.6% at 2 years. We conclude that allogeneic HSCT is a safe and effective option for carefully selected patients age 70 or older.

Treatment of older patients with acute myeloid leukemia (AML): a Canadian consensus

Patients over age 60 comprise the majority of those diagnosed with acute myeloid leukemia (AML), but treatment approaches in this population are variable, with many uncertainties and controversies. Our group conducted a literature review to summarize the latest information and to develop a consensus document with practical treatment recommendations. We addressed five key questions: selection criteria for patients to receive intensive induction chemotherapy; optimal induction and post-remission regimens; allogeneic hematopoietic stem cell transplantation (HSCT); treatment of patients not suitable for induction chemotherapy; and treatment of patients with prior hematological disorders or therapy-related AML. Relevant literature was identified through a PubMed search of publications from 1991 to 2012. Key findings included the recognition that cytogenetics and molecular markers are major biologic determinants of treatment outcomes in the older population, both during induction therapy and following HSCT. Although disease-specific and patient-specific risk factors for poor outcomes are more common in the older population, age is not in itself sufficient grounds for withholding established treatments, including induction and consolidation chemotherapy. The role of HSCT and use of hypomethylating agents are discussed. Finally, suggested treatment algorithms are outlined, based on these recommendations.

Autologous blood cell transplantation versus HLA-identical sibling transplantation for acute myeloid leukemia in first complete remission: a registry study from the Center for International Blood and Marrow Transplantation Research

The optimal post-remission treatment for acute myeloid leukemia in first complete remission remains uncertain. Previous comparisons of autologous versus allogeneic hematopoietic cell transplantation noted higher relapse, but lower treatment-related mortality though using bone marrow grafts, with treatment-related mortality of 12-20%. Recognizing lower treatment-related mortality using autologous peripheral blood grafts, in an analysis of registry data from the Center for International Blood and Transplant Research, we compared treatment-related mortality, relapse, leukemia-free survival, and overall survival for patients with acute myeloid leukemia in first complete remission (median ages 36-44, range 19-60) receiving myeloablative HLA-matched sibling donor grafts (bone marrow, n=475 or peripheral blood, n=428) versus autologous peripheral blood (n=230). The 5-year cumulative incidence of treatment-related mortality was 19% (95% confidence interval, 16-23%), 20% (17-24%) and 8% (5-12%) for allogeneic bone marrow, allogeneic peripheral blood and autologous peripheral blood stem cell transplant recipients, respectively. The corresponding figures for 5-year cumulative incidence of relapse were 20% (17-24%), 26% (21-30%) and 45% (38-52%), respectively. At 5 years, leukemia-free survival and overall survival rates were similar: allogeneic bone marrow 61% (56-65%) and 64% (59-68%); allogeneic peripheral blood 54% (49-59%) and 59% (54-64%); autologous peripheral blood 47% (40-54%) and 54% (47-60%); P=0.13 and P=0.19, respectively. In multivariate analysis the incidence of treatment-related mortality was lower after autologous peripheral blood transplantation than after allogeneic bone marrow/peripheral blood transplants [relative risk 0.37 (0.20-0.69); P=0.001], but treatment failure (death or relapse) after autologous peripheral blood was significantly more likely [relative risk 1.32 (1.06-1.64); P=0.011]. The 5-year overall survival, however, was similar in patients who received autologous peripheral blood (n=230) [relative risk 1.23 (0.98-1.55); P=0.071] or allogeneic bone marrow/peripheral blood (n=903). In the absence of an HLA-matched sibling donor, autologous peripheral blood may provide acceptable alternative post-remission therapy for patients with acute myeloid leukemia in first complete remission.