Assessment of Differences in Patient Populations Selected for or Excluded From Participation in Clinical Phase III Acute Myelogenous Leukemia Trials

Identifying barriers associated with enrollment of patients with lung cancer into clinical trials

BACKGROUND

Enrollment of patients with lung cancer into clinical trials is required to accelerate the pace of new therapy development and contribute to a better understanding of the biological characteristics of cancer.

METHODS

We conducted a retrospective chart review of all patients seen by the thoracic medical oncology team at the Vanderbilt Ingram Cancer Center (VICC) from November 2005 to November 2008 to determine the barriers associated with patient enrollment in to clinical trials.

RESULTS

One thousand forty-three patient charts were audited: 32% of patients were eligible for enrollment, and 14% enrolled in a study. There were no significant differences in protocol availability or eligibility by sex, smoking status, or age. Patients living further from the cancer center were significantly less likely to have a study protocol available (P = .009), but if a protocol was available they were more likely to be eligible for enrollment (P < .001). Significantly more protocols were available for patients with non-small-cell lung cancer (NSCLC) compared with those who had small-cell lung cancer (SCLC) (63% vs. 48%; P < .001). Patients with advanced disease were more likely to have a protocol available (P < .001) and enter a study (P = .031). The most common reasons for patients not being eligible for enrollment were poor performance status (32%) and presence of comorbid disease (27%). The most common reasons for potentially eligible patients not enrolling in a study included preference for treatment closer to home (49%) and patient refusal (43%).

CONCLUSION

Additional strategies are required to increase accrual of patients into lung cancer trials, including development of protocols for early-stage disease and modifying eligibility and performance status criteria for this unique patient population.

Intensive care unit management of patients with newly diagnosed acute myeloid leukemia with no organ failure

Patients with acute myeloid leukemia (AML) may present with early complications from sepsis or leukemic infiltration. Benefits from early in-intensive care unit (ICU) hematological management was evaluated in 42 adults with newly diagnosed AML with hematological risk of early death (age 46 years, French-American-British [FAB] M4/5 58%, leukocytes 103 × 10(9)/L) first admitted to the ICU without immediate life support (early-ICU). Controls were 42 patients primarily admitted to hematology wards, matched for age, leukocytes and FAB subtype. Twenty (47.6%) control patients were subsequently admitted to the ICU (late-ICU). Late-ICU patients presented with increased respiratory and cardiac rates, decreased oxygen saturation (SpO(2)) and blood pressure, at hospital admission. Late-ICU admission resulted in increased use of mechanical ventilation (60% vs. 33%) and vasopressors (60% vs. 16%), longer ICU stay (9 [6-25] vs. 5 [2-9] days) and decreased ICU survival (65% vs. 79%). Direct admission to the ICU of patients with high-risk AML with physiological disturbances but no organ dysfunction is associated with improved outcomes.

Treatment of acute promyelocytic leukemia for older patients

Acute promyelocytic leukemia (APL) represents a remarkable disease in which leukemogenesis is driven by the PML-RARα oncogene and for which targeted treatment with all-trans retinoic acid (ATRA)-based therapy allows substantial chance of cure. APL is seen in a small subset of older patients, with age representing one of the most important prognostic factors for outcome of treatment. Unlike other acute leukemias, the inferior outcomes for APL in older patients relates less to changes in disease biology and more to the increased toxicity of ATRA and the chemotherapy combination regimens used to induce hematologic and molecular responses. Risk-adapted strategies that use less-toxic agents, such as arsenic trioxide, allow treatment of older patients, with greater efficiency and better chances of cure.

Evaluation of factors associated with recruitment in hematological clinical trials: a retrospective cohort study

The objectives of this study were to measure the recruitment, to study characteristics associated with recruitment, and to explore reasons for non-recruitment in clinical trials for malignant hematological diseases. Trials opened between 2002 and 2008 were selected. If the patient fulfilled the main criteria of the protocol, all eligibility criteria of the protocol were assessed. A total of 1394 patients-protocol were identified in 17 protocols (697 patients, since a patient could have been eligible for more than one protocol) and 195 patients-protocol (186 patients) of these fulfilled the main criteria of the protocol. Among the 195 patients-protocol, 133 (68·2%) fulfilled all the eligibility criteria and 45 (23·1%) were recruited. Patients, physicians, and protocol characteristics were not associated with recruitment. The most common reasons for not being recruited were as follow: 40·7%, not fulfilling all eligibility criteria; 31·3%, protocol not being proposed according to the chart; and 22·7%, patients' refusal.

Shortcomings in the clinical evaluation of new drugs: acute myeloid leukemia as paradigm

Drugs introduced over the past 25 years have benefitted many patients with acute myeloid leukemia (AML) and provided cure for some. Still, AML remains difficult to treat, and most patients will eventually die from their disease. Therefore, novel drugs and drug combinations are under intense investigation, and promising results eagerly awaited and embraced. However, drug development is lengthy and costs are staggering. While the phase 1-phase 2-phase 3 sequence of clinical drug testing has remained inviolate for decades, it appears intrinsically inefficient, and scientific flaws have been noted by many authors. Of major concern is the high frequency of false-positive results obtained in phase 2 studies. Here, we review features of phase 2 trials in AML that may contribute to this problem, particularly lack of control groups, patient heterogeneity, selection bias, and choice of end points. Recognizing these problems and challenges should provide us with opportunities to make drug development more efficient and less costly. We also suggest strategies for trial design improvement. Although our focus is on the treatment of AML, the principles that we highlight should be broadly applicable to the evaluation of new treatments for a variety of diseases.

Diagnosis and management of acute myeloid leukemia in adults: recommendations from an international expert panel, on behalf of the European LeukemiaNet

In 2003, an international working group last reported on recommendations for diagnosis, response assessment, and treatment outcomes in acute myeloid leukemia (AML). Since that time, considerable progress has been made in elucidating the molecular pathogenesis of the disease that has resulted in the identification of new diagnostic and prognostic markers. Furthermore, therapies are now being developed that target disease-associated molecular defects. Recent developments prompted an international expert panel to provide updated evidence- and expert opinion–based recommendations for the diagnosis and management of AML, that contain both minimal requirements for general practice as well as standards for clinical trials. A new standardized reporting system for correlation of cytogenetic and molecular genetic data with clinical data is proposed.

Feasibility of autologous peripheral blood stem cell transplantation in elderly patients with acute myeloid leukemia

Most studies showing that autologous stem cell transplantation (ASCT) is feasible in older patients with acute myeloid leukemia (AML) referred to highly selected patients considered as eligible after complete remission (CR) achievement and bone marrow or peripheral blood stem cell (PBSC) collection. This study evaluated the feasibility of ASCT from 155 consecutive AML patients aged over 60 years (median age 72 years, range 61 - 94) programmed to receive ASCT by using PBSCs after CR achievement. Overall, 90 out of 155 patients (58%) were judged as eligible for aggressive chemotherapy and 45 (50%) achieved CR. Among these, 36 (80%) received consolidation and 32 (89% of consolidated) were monitored for PBSC mobilization. A successful collection was registered in 25/32 patients (78% of monitored). Finally, 20 patients received ASCT. Reasons for not autografting five mobilizing patients included relapse pre-ASCT, toxicity, and refusal. Median survival was 4 months for the whole patient population and 19 months for patients actually autografted. Overall, 20 out of 90 patients accrued into intensive chemotherapy (22%) and 20 out of the entire patient population (13%) underwent ASCT. It is concluded that APBSCT can result in an improvement of therapeutic results in AML of the elderly, but it is feasible in a minority of selected patients.

De novo acute myeloid leukemia in adults younger than 60 years of age: Socioeconomic aspects and treatment results in a Brazilian university center

We retrospectively studied the outcomes of adults with de novo acute myeloid leukemia treated in a reference center in Brazil and analyzed the association with the human development index (HDI) of the United Nations used as a socioeconomic factor. Among 123 patients, 46 (37%) died during induction, 65 (53%) reached complete remission and 45 (37%) received high-dose cytarabine (Hidac) consolidation. The 5-year overall survival and leukemia-free survival (LFS) were 17 and 26%, respectively, for all patients and 36 and 30%, respectively, for those receiving Hidac. In multivariate analysis, an HDI <0.660 was associated with a lower probability to receive Hidac (P = 0.001), a trend for higher mortality in remission induction (P = 0.062) and a decreased LFS (P < 0.0001). However, it was not associated with outcomes for patients receiving Hidac. In conclusion, survival for patients who received Hidac consolidation is satisfactory; however, socioeconomic factors may have selected patients to receive intensive Hidac consolidation.

Acute myelogenous leukemia in older adults

The incidence of acute myelogenous leukemia (AML) increases with age. Older AML patients, generally defined by age > or = 60 years, have worse treatment outcomes than younger patients. While selected older patients can benefit from standard therapies, as a group they experience greater treatment-related toxicity, lower remission rates, shorter disease-free survival times, and shorter overall survival times. Outcome disparity is in part explained by age-related biologic features. Older patients are more likely to present with unfavorable cytogenetic abnormalities, multidrug resistance phenotypes, and secondary AML. However, even older adults with favorable tumor biology have a worse prognosis than younger patients. Patient-specific factors, including impaired physical function and comorbidity, independently predict greater treatment toxicity and shorter survival. Improving patient assessment strategies is critical to identify those patients who are most likely to benefit from induction and postremission therapies. In addition, continued efforts to identify more effective and tolerable induction and postremission strategies are needed for this population. Investigations of hypomethylating agents and signal transduction inhibitors hold promise for the treatment of AML patients. Steady advances in the field of hematopoietic transplantation, including use of reduced intensity transplants, may result in additional curative options available to selected older adults. Finally, improved supportive care strategies are needed to maximize treatment outcomes.

Patterns of recruitment into acute myeloid leukaemia (AML) 15 and outcome for young patients with AML at a single referral centre

This study assessed the recruitment to an acute myeloid leukaemia (AML) trial (AML15) in a single centre, evaluated whether outcome was influenced by trial entry and whether the trial population could be considered representative of all AML patients by retrospective comparison of patient characteristics, trial entry and outcome for 81 consecutive patients (<60 years). All patients were considered for trial entry, however the trial was not offered to 12 (15%) patients. These patients had a worse outcome than the 69 (85%) patients that were invited to participate (P = 0.04). Sixteen patients (23%) invited to participate in the trial declined and were treated on equivalent protocols. These patients had a similar outcome to those who accepted entry into the trial (P = 0.2). These results suggested that physicians exert a selection bias when evaluating patients for trial entry. Thus the overall survival estimates generated from large phase III trials may indicate that the outcome for patients with AML is better than the outcome experienced in the 'real' world. Furthermore, patients who are considered appropriate for randomization into a trial, but decline entry, experience a similar outcome to those treated on trial when treated in an equivalent manner.

Age and acute myeloid leukemia: real world data on decision to treat and outcomes from the Swedish Acute Leukemia Registry

Acute myeloid leukemia (AML) is most common in the elderly, and most elderly are thought to be unfit for intensive treatment because of the risk of fatal toxicity. The Swedish Acute Leukemia Registry covers 98% of all patients with AML (nonacute promyelocytic leukemia) diagnosed in 1997 to 2005 (n = 2767), with a median follow-up of 5 years, and reports eligibility for intensive therapy, performance status (PS), complete remission rates, and survival. Outcomes were strongly age and PS dependent. Early death rates were always lower with intensive therapy than with palliation only. Long-term survivors were found among elderly given intensive treatment despite poor initial PS. Total survival of elderly AML patients was better in the geographic regions where most of them were given standard intensive therapy. This analysis provides unique real world data from a large, complete, and unselected AML population, both treated and untreated, and gives background to treatment decisions for the elderly. Standard intensive treatment improves early death rates and long-term survival compared with palliation. Most AML patients up to 80 years of age should be considered fit for intensive therapy, and new therapies must be compared with standard induction.

Somatic CEBPA mutations are a frequent second event in families with germline CEBPA mutations and familial acute myeloid leukemia

PURPOSE

The transcription factor CCAAT/enhancer binding protein-alpha (CEBPA) is crucial for normal myeloid differentiation. Mutations in the CEBPA gene are found in subsets of patients with acute myeloid leukemia (AML). Recently, three families were reported in whom several family members had germline CEBPA mutations and subsequently developed AML. Whereas familial AML is considered a rare event, the frequency of CEBPA germline mutations in AML is not known.

PATIENTS AND METHODS

In this study, we screened 187 consecutive AML patients for CEBPA mutations at diagnosis. We detected 18 patients (9.6%) with CEBPA mutations. We then analyzed remission samples and constitutive DNA from these patients.

RESULTS

We found that two (11.1%) of 18 AML patients with CEBPA mutations carried a germline N-terminal frameshift CEBPA mutation. Interestingly, additional members in the families of both of these patients have been affected by AML, and the germline CEBPA mutations were also observed in these patients. Additional somatic mutations in AML patients with germline CEBPA mutations in the two families comprised in-frame C-terminal CEBPA mutations in two patients, two nonsilent CEBPA point mutations in one patient, and monosomy 7 in one patient.

CONCLUSION

This study shows, for the first time to our knowledge, that germline CEBPA mutations are frequently observed among AML patients with CEBPA mutations. Including the families with germline CEBPA mutations reported previously, additional somatic CEBPA mutations represent a frequent second event in AML with germline CEBPA mutations. Our data strongly indicate that germline CEBPA mutations predispose to AML and that additional somatic CEBPA mutations contribute to the development of the disease.

Relevance of clinical trials in acute myeloid leukaemia

Patients with newly diagnosed acute myeloid leukaemia (AML) are increasingly being enrolled in clinical trials sponsored by pharmaceutical companies or the National Cancer Institute. These trials routinely exclude patients who are less likely to respond (LLTR), e.g. those with Zubrod performance status >2 and levels of bilirubin or creatinine >/=2.0 mg/dL. Here we examine rates of enrollment of LLTR patients in clinical trials over the past 16 years. Overall, 2323 adults with newly diagnosed AML (excluding acute promyelocytic leukaemia) were registered on clinical trials from 1991 to 2006. LLTR patients constituted a significantly smaller proportion of the patients enrolled from 1999 to 2006 than from 1991 to 1998 (p < 0.0001, considering all patients and patients 60 years or older). While 54% of patients considered 'more likely to respond' (MLTR) (i.e. those with performance status <3, bilirubin <2.0 mg/dL and creatinine <2.0 mg/dL) were enrolled in these studies from 1999 to 2006, only 36% of LLTR patients were enrolled during this period (p < 0.0001). Our results suggest that newer clinical trials may be less applicable to LLTR patients than previous trials. There is a need for clinical trials specific to the LLTR population, the group most in need of novel therapies.

Acute Myeloid Leukemia: Epidemiology and Etiology

Although acute leukemias are infrequent diseases, they are highly malignant neoplasms responsible for a large number of cancer-related deaths. Acute myeloid leukemia (AML) is the most common type of leukemia in adults, yet continues to have the lowest survival rate of all leukemias. While results of treatment have improved steadily in younger adults over the past 20 years, there have been limited changes in survival among individuals of age >60 years [1, 2].

Comparable non-relapse mortality and survival after HLA-identical sibling blood stem cell transplantation with reduced or conventional-intensity preparative regimens for high-risk myelodysplasia or acute myeloid leukemia in first remission

We prospectively compared two strategies of allogeneic PBSCT from HLA-identical siblings in adults with poor-risk AML or myelodysplastic syndrome with >5% marrow blasts in an early disease status (AML or refractory anemia with excess blasts (RAEB type 2) in first remission after chemotherapy or untreated RAEB type 1). Based only on age, all consecutive patients were offered one of two specific transplant protocols. Patients < or =50 years old received conventional high-dose conditioning with cyclophosphamide-TBI and use of CD34+-selected PBSCT (CTCD34+ group), while patients aged >50 years received a reduced-intensity conditioning (RIC) with fludarabine and oral busulphan (FB-RIC). Seventy-five patients entered the study (35 in the CTCD34+ and 39 in the FB-RIC group). The median follow-up was >4 years in both groups. The 4-year non-relapse mortality (NRM) was 19 and 20%, respectively (P=0.8). Relapse and survival were also equivalent in both groups. These results suggest that in this setting, the expected high NRM in elderly patients can be reduced with an RIC regimen.

Treatment of older patients with acute myeloid leukemia

In recent years, major advances have been made in the treatment of acute myeloid leukemia (AML) in younger patients, but the prognosis for elderly AML patients remains poor. This review focuses on current and emerging data on the treatment of AML in the elderly. Most elderly patients are not considered for induction therapy. Cytarabine and anthracycline combination therapies induce remission in up to 50% of cases of newly diagnosed AML, and the median survival duration ranges between 5 and 10 months. Targeted therapies such as monoclonal antibodies (gemtuzumab ozogamicin), farnesyltransferase inhibitors (tipifarnib), tyrosine kinase inhibitors (lestaurtinib) and hypomethylating agents (decitabine and valproic acid) are being investigated in elderly patients with AML. Autologous and reduced-intensity allogeneic stem cell transplantation has been used in selected patients.

Acute myeloid leukemia and myelodysplastic syndromes in older patients

The median age of patients with acute myeloid leukemia (AML) is 65 to 70 years. The majority of older patients with AML probably do not receive specific treatment, and those who receive standard regimens have a median survival time of less than 1 year. This suggests that, in general, older patients should receive investigational therapy; however, factors other than age influence survival after administration of standard treatment and need to be accounted for when making treatment recommendations. In some cases where investigational therapy is unavailable, palliative care may be the best option. Like AML, myelodysplastic syndrome (MDS) is a disease of the elderly. It is divided into higher and lower risk groups. The natural history of high-risk MDS (eg, > 10% marrow blasts) bears more resemblance to that of AML than to that of an indolent disorder; accordingly, similar therapeutic considerations apply. The more benign natural history of lower risk MDS leads to consideration of reduction in transfusion needs and improvement in quality of life as primary goals of therapy. Lenalidomide, azacitidine, and decitabine, each recently approved by the US Food and Drug Administration, are useful in achieving these objectives.

Cloretazine (VNP40101M), a Novel Sulfonylhydrazine Alkylating Agent, in Patients Age 60 Years or Older With Previously Untreated Acute Myeloid Leukemia

Purpose

Cloretazine (VNP40101M) is a sulfonylhydrazine alkylating agent with significant antileukemia activity. A multicenter phase II study of cloretazine was conducted in patients 60 years of age or older with previously untreated acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (MDS).

Patients and Methods

Cloretazine 600 mg/m2was administered as a single intravenous infusion. Patients were stratified by age, performance score, cytogenetic risk category, type of AML, and comorbidity.

Results

One hundred four patients, median age 72 years (range, 60 to 84 years), were treated on study. Performance status was 2 in 31 patients (30%) and no patient had a favorable karyotype. Forty-seven patients (45%) had cardiac disease, 25 patients (24%) had hepatic disease, and 19 patients (18%) had pulmonary disease, defined as per the Hematopoietic Cell Transplantation–Specific Comorbidity Index, at study entry. The overall response rate was 32%, with 29 patients (28%) achieving complete response (CR) and four patients (4%) achieving CR with incomplete platelet recovery. Response rates in 44 de novo AML patients, 45 secondary AML patients, and 15 high-risk MDS patients were 50%, 11%, and 40%, respectively. Response by cytogenetic risk category was 39% in 56 patients with intermediate cytogenetic risk and 24% in 46 patients with unfavorable cytogenetic risk. Nineteen (18%) patients died within 30 days of receiving cloretazine therapy. Median overall survival was 94 days, with a 1-year survival of 14%; the median duration of survival was 147 days, with a 1-year survival of 28% for those who achieved CR.

Conclusion

Cloretazine has significant activity and modest extramedullary toxicity in elderly patients with AML or high-risk MDS. Response rates remain consistent despite increasing age and comorbidity.

Acute myeloid leukemia: epidemiology and etiology

Acute myeloid leukemias (AMLs) are infrequent, yet highly malignant neoplasms responsible for a large number of cancer-related deaths. The incidence has been near stable over the last years. It continuously shows 2 peaks in occurrence in early childhood and later adulthood. With an incidence of 3.7 per 100,000 persons and an age-dependent mortality of 2.7 to nearly 18 per 100,000 persons, there is a rising awareness in the Western world of AML's special attributes resulting from an ever-aging population. To objectively describe epidemiologic data on this patient population, recent publications were evaluated to make transparent the current trends and facts. A review of the literature is presented, reflecting highlights of current research with respect to AML etiology. To estimate outcome and discuss informed treatment decisions with AML patients of different age groups and different biologic risk categories, it is mandatory to consider that the outcome results reported in clinical trials were until now heavily biased toward younger patients, whereas the overall dismal prognosis documented in population-based studies most likely reflects the exclusion of older patients from aggressive treatment. The etiology for most cases of AML is unclear, but a growing knowledge concerning leukemogenenic agents within chemotherapy regimens for other malignancies is already available. This includes specific associations of the most frequent balanced translocations in AML, including the "good-risk" abnormalities comprised by the core binding factor leukemias (i.e., AML with the translocation (8;21) and inversion of chromosome 16, and acute promyelocytic leukemia with the translocation (15;17)). In contrast to these genetic alterations, epigenetic lesions, e.g., promoter silencing by hypermethylation of the p15/INK4b and other genes, are increasingly recognized as important in the pathogenesis of AML.

Attitude towards remission induction for elderly patients with acute myeloid leukemia influences survival

Combination chemotherapy may induce remission from acute myeloid leukemia (AML), but validated criteria for treatment of elderly are lacking. The remission intention (RI) rate for elderly patients, as reported to the Swedish Leukemia Registry, was known to be different when comparing the six health care regions, but the consequences of different management are unknown. The Leukemia Registry, containing 1672 AML patients diagnosed between 1997 and 2001, with 98% coverage and a median follow-up of 4 years, was completed with data from the compulsory cancer and population registries. Among 506 treated and untreated patients aged 70-79 years with AML (non-APL), there was a direct correlation between the RI rate in each health region (range 36-76%) and the two-year overall survival, with no censored observations (6-21%) (chi-squared for trend=11.3, P<0.001; r2=0.86, P<0.02, nonparametric). A 1-month landmark analysis showed significantly better survival in regions with higher RI rates (P=0.003). Differences could not be explained by demographics, and was found in both de novo and secondary leukemias. The 5-year survival of the overall population aged 70-79 years was similar between the regions. Survival of 70-79-year-old AML patients is better in regions where more elderly patients are judged eligible for remission induction.

An antecedent diagnosis of refractory anemia with excess blasts has no prognostic relevance in acute myeloid leukemia of older adult patients

BACKGROUND

Conflicting results have been reported about the prognostic relevance of antecedent myelodysplastic syndrome (MDS) in acute myeloid leukemia (AML) of older adults.

PATIENTS AND METHODS

Data from 87 intensively treated AML patients (median age 69 years) were analyzed, with the aim of comparing therapeutic results and toxicity between de novo and AML secondary to a previous MDS (s-AML). Rate of CD34+ cells mobilization and feasibility of autologous stem cell transplantation (ASCT) were also compared.

RESULTS

Complete remission rate, death in induction and primary resistance were not statistically different between the two groups. Median time for neutrophil recovery was similar, while s-AML patients required a longer time for platelet recovery (P = 0.04). There was no difference as to eligibility for consolidation as well as for mobilization and feasibility of ASCT. S-AML had negligible impact on overall survival (OS) and disease-free survival (DFS). In the multivariate analysis the only parameter significantly related to either OS or DFS duration was adverse karyotype (P = 0.02 and 0.04, respectively).

CONCLUSIONS

A diagnosis of s-AML does not represent a clinically relevant prognostic factor in elderly AML patients treated with aggressive therapy. Furthermore, s-AML patients can be mobilized and autografted with comparable results as opposed to de novo cases.

Factors influencing inclusion of patients with malignancies in clinical trials

Participation in clinical trials remains low and is a central issue in oncology. The authors identified, through a systematic review, 75 papers published up to August 2004 that report barriers to recruitment of patients in clinical trials. These barriers range from patient preference and concern about information/consent to clinical problems with protocols. Strategies to overcome barriers on the part of patients and clinicians are needed and should be carefully evaluated. Thirty-three (44%) papers reported factors related to patients as influencing the inclusion of patients, 28 (37%) reported clinician's related factors, and 37 (49%) other factors from either specific groups of patients (30 papers, 40%) and/or other scopes (13 papers, 17%). No differences in prevalence were found between papers dedicated to hematologic malignancies and solid tumors. Factors related to clinicians as influential were more frequently reported before 1995 (70%) than thereafter (25%; P = 0.0009). Reporting specific groups of patients as influential was more frequent in North American articles (50%) than in others (14%, P = 0.008). Patients' barriers included mostly patient preference (12 papers), concern about information and/or consent (11 papers), worry about uncertainty (7 papers), and/or relationship with medical team (7 papers). Concerning clinicians, incompatibility of protocol with normal practice (nine papers), problems in complying with the protocol (eight papers), and/or consent procedure (eight papers) were the most reported factors. The remaining factors mostly relied on specific groups of patients (30 papers), notably age of patients (18 papers) and/or minority population (11 papers, all from the USA). Strategies to overcome these barriers are needed and should be carefully evaluated.

Age and acute myeloid leukemia

We conducted a retrospective analysis of 968 adults with acute myeloid leukemia (AML) on 5 recent Southwest Oncology Group trials to understand how the nature of AML changes with age. Older study patients with AML presented with poorer performance status, lower white blood cell counts, and a lower percentage of marrow blasts. Multidrug resistance was found in 33% of AMLs in patients younger than age 56 compared with 57% in patients older than 75. The percentage of patients with favorable cytogenetics dropped from 17% in those younger than age 56 to 4% in those older than 75. In contrast, the proportion of patients with unfavorable cytogenetics increased from 35% in those younger than age 56 to 51% in patients older than 75. Particularly striking were the increases in abnormalities of chromosomes 5, 7, and 17 among the elderly. The increased incidence of unfavorable cytogenetics contributed to their poorer outcome, and, within each cytogenetic risk group, treatment outcome deteriorated markedly with age. Finally, the combination of a poor performance status and advanced age identified a group of patients with a very high likelihood of dying within 30 days of initiating induction therapy. The distinct biology and clinical responses seen argue for age-specific assessments when evaluating therapies for AML.

Treatment of older patients with AML

Undertreatment of the older patients with AML can explain, in part, their inferior outcome when compared with that in younger patients. In analogy to the benefit of patients under the age of 60 years from high-dose AraC there are dosage related therapeutic effects in the patients over 60 years in particular for daunorubicin in the induction treatment, and for maintenance versus no maintenance in the post-remission treatment. Utilizing these effects can partly overcome the mostly unfavorable disease biology in older age AML, whereas the role of risk factors involved is not completely understood and the concept of dose-response needs to be requestioned. We recommend an adequate dosage of 60 mg/(m2day) daunorubicin for 3 days in a combination with standard dose AraC and 6-thioguanine given for induction and consolidation and followed by a prolonged monthly maintenance chemotherapy. Further improvements in supportive care may help delivering additional anti-leukemic cytotoxicity. As a novel approach, reduced toxicity preparative regimens may open up allogeneic transplantation for older patients with AML. Other new options like MDR modulators, antibody targeted therapies and tyrosine kinase inhibitors are under clinical investigation. A questionnaire study in patients with AML showed that according to patients' self-assessment intensive and prolonged treatment did not result in decreasing quality of life. This finding did not vary by age under or above 60 years. Given the actual median age in this disease being more than 60 years the adequate management of older age AML remains as the major challenge.

Disease biology rather than age is the most important determinant of survival of patients ≥ 60 years with acute myeloid leukemia treated with uniform intensive therapy

BACKGROUND

The objectives of the current study were to evaluate the outcome of patients > or = 60 years with acute myeloid leukemia (AML) treated uniformly with high-dose daunorubicin containing induction and modified high-dose cytosine arabinoside containing postremission therapy, and to identify factors predictive of complete disease remission (CR) and survival.

METHODS

Between 1998 and 2002, the authors treated 117 newly diagnosed patients (acute promyelocytic leukemia excluded) with AML > or = 60 years (median, 67 years; range, 60-82 years). Karyotype (Medical Research Council classification) at diagnosis was categorized as good risk (n = 3), intermediate risk (n = 69), adverse risk (n = 26), and suboptimal/not done (n = 19). A normal karyotype was seen in 41 patients and 40 (34%) had secondary AML.

RESULTS

The outcome of induction included the following: CR, 62 (53%); early death, 5 (4%); death during hypoplasia, 14 (12%); and resistant disease, 36 (31%). The 3-year event-free (EFS) and overall survival (OS) rates were 9% (95% confidence interval [95% CI], 3-16%) and 17% (95% CI, 9-29%), respectively. In a univariate analysis, cytogenetics, lactate dehydrogenase level, leukocyte count, and performance status were the significant factors for EFS and OS. Age was not a significant prognostic factor for either CR or survival. In a multivariate model, adverse-risk cytogenetics, previous history of myelodysplastic syndrome or antecedent hematologic disorder, and high leukocyte count (> 30 x 10(9)/L) were independent adverse prognostic factors for survival. The impact of adverse karyotype on EFS and OS was time dependent and was observed after 50 and 150 days, respectively.

CONCLUSIONS

The authors concluded that candidacy for intensive therapy in older patients should be based on biologic features of disease and fitness, rather than on age.