Granulocyte-macrophage colony-stimulating factor after initial chemotherapy for elderly patients with primary acute myelogenous leukemia. Cancer and Leukemia Group B

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.

Phase II trial of arsenic trioxide in relapsed and refractory acute myeloid leukemia, secondary leukemia and/or newly diagnosed patients at least 65 years old

The prognosis for patients with relapsed/refractory AML, secondary leukemia and AML in older adults is extremely poor. An appealing alternative approach to intensive cytotoxic chemotherapy is to induce apoptosis with a novel agent. There is in vitro evidence that arsenic trioxide (ATO) has anti-proliferative and pro-apoptotic effects on myeloid leukemia cell lines. To evaluate efficacy and toxicities of ATO, we conducted a phase II trial including subjects with relapsed/refractory or secondary AML or age > or = 65 years with de novo disease. Eleven subjects were entered with a median age of 77 years (56-90) and a median total dose of ATO of 415.55 mg (91.5-793) with a daily dose of 0.25 mg/kg. Median survival following the first dose of ATO was 2.25 months (0.4-19). Myelosuppression was the major adverse effect, most likely due to disease progression rather than drug-related. All subjects had progressive disease. There was no direct treatment-related mortality. Based on this study, we do not recommend single agent ATO as a treatment option for AML.

Acute myeloid leukemia in the older patient

Acute myeloid leukemia (AML) is an extremely heterogeneous disorder. The biology of AML is incompletely understood, but much data indicates that older patients have a more biologically diverse and chemotherapy resistant form of AML that is quite different from that seen in the younger patients. Approximately 60% of AML cases are in patients greater than 60 years of age, so the predominant burden is in older patients. This problem will be magnified in the future, because the US population is both growing and aging. When one examines the treatment outcomes of older AML patients over the last three decades, there is little progress in long-term survival. Nine major published randomized placebo controlled trials of myeloid growth factors given during induction for AML have been conducted. All of these trials with one exception demonstrated no significant impact on the clinical outcomes of complete response (CR) rate, disease-free, and overall survival. However, the duration of neutropenia was consistently and uniformly reduced by the use of growth factor in all nine of these trials. Because of the favorable impact of the colony-stimulating factors (CSFs) on resource use, antibiotic days, hospital days, etc., it can be more economical and beneficial to use CSFs in AML than to withhold use. The overall dismal outlook for the older AML patient can only be altered by clinical trials with new therapeutic agents. New cellular and molecularly targeted agents are entering clinical trials and bring hope for progress to this area of cancer therapy.

Unanswered questions in acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a heterogeneous disease that presents with a range of morphological, cytogenetic, immunophenotypic, and biomolecular features. Over the past 20 years, application of new cytogenetic and molecular techniques has greatly improved knowledge of the pathophysiology of AML, resulting in new potential therapeutic applications. However, the results of current therapy are still unsatisfactory, especially in patients who have adverse prognostic factors at the time of diagnosis. Furthermore, some pivotal questions about the procedures of induction and postinduction therapy of AML remain unanswered, and substantial controversy exists on the optimum therapeutic approach for the disorder.

A Novel Effective and Safe Consolidation for Patients Over 60 Years with Acute Myeloid Leukemia

PURPOSE

High-dose intermittent cytarabine is an effective postremission treatment for patients with acute myeloid leukemia (AML). This regimen is a safe approach in patients < 60 years but produced severe neurotoxicity in the elderly.

EXPERIMENTAL DESIGN

We have established a dose-reduced age-adapted consolidation using intermediate dose (IDAC; 2 x 1 g/m(2) i.v., days 1, 3, and 5) for AML patients >/= 60 years. Forty-seven de novo AML patients in complete remission (CR; median age, 70 years) were scheduled to receive four consolidation cycles of IDAC.

RESULTS

In 25 of 47 patients (53%), all four cycles were administered: 9 (19%) received three cycles; 7 (15%) received two cycles; and 6 patients (12%) one cycle. Treatment was well tolerated without neurotoxicity. The median number of days with severe neutropenia (absolute neutrophil count < 500/microl) was 9. Neutropenic fever occurred in 22 of 47 patients (49%) during the first cycle, in 24 of 41 (60%) during the second, in 15 of 34 (44%) during the third, and in 18 of 25 (72%) during the fourth cycle. Only 1 patient died during consolidation (cardiac failure). The median overall survival, disease-free survival, and continuous CR were 10.6, 15.5, and 15.9 months, respectively. The probability of overall survival, disease-free survival, and continuous CR at 5 years were 18, 22, and 30%, respectively.

CONCLUSIONS

IDAC is a safe and effective postremission therapy for elderly patients with AML.

Abnormal Cytogenetics at Date of Morphologic Complete Remission Predicts Short Overall and Disease-Free Survival, and Higher Relapse Rate in Adult Acute Myeloid Leukemia: Results From Cancer and Leukemia Group B Study 8461

Purpose

As most patients with acute myeloid leukemia (AML) with morphologic complete remission (CR) ultimately relapse, better predictors for outcome are needed. Recently, Cheson et al suggested using cytogenetic remission (CRc) as part of the criteria for CR. To our knowledge, ours is the first relatively large study evaluating the usefulness of CRc attained immediately following induction chemotherapy.

Patients and Methods

We included AML patients treated on Cancer and Leukemia Group B front-line studies with cytogenetic samples obtained at diagnosis and at the first day of documented CR following induction. Patients with abnormal cytogenetics at diagnosis, and normal cytogenetics at CR (NCR; n = 103) were compared with those with abnormal cytogenetics both at diagnosis and at CR (ACR; n = 15) for overall survival (OS), disease-free survival (DFS), and cumulative incidence of relapse (CIR). Cox proportional hazards models determined the prognostic significance of cytogenetics at CR, adjusting for other covariates.

Results

Clinical features were similar for both groups, with the exception of favorable cytogenetics [t(8;21), inv(16)/t(16;16), t(15;17)] at diagnosis, which was more frequent (P = .03) in the NCR group. Median follow-up was 3.1 years (range, 1.0 to 11.4 years). ACR patients had significantly shorter OS (P = .006) and DFS (P = .0001), and higher CIR (P = .0001). In multivariable models, the NCR and ACR groups were predictors for OS (P = .03), DFS (P = .02), and CIR (P = .05). The relative risk of relapse or death was 2.1 times higher for ACR patients than for NCR patients (95% CI, 1.1 to 3.9).

Conclusion

Our data suggest that converting to normal karyotype at the time of first CR is an important prognostic indicator and support the use of CRc as a criterion of CR in AML.

Optimal Estimator for the Survival Distribution and Related Quantities for Treatment Policies in Two‐Stage Randomization Designs in Clinical Trials

Two-stage designs, where patients are initially randomized to an induction therapy and then depending upon their response and consent, are randomized to a maintenance therapy, are common in cancer and other clinical trials. The goal is to compare different combinations of primary and maintenance therapies to find the combination that is most beneficial. In practice, the analysis is usually conducted in two separate stages which does not directly address the major objective of finding the best combination. Recently Lunceford, Davidian, and Tsiatis (2002, Biometrics58, 48-57) introduced ad hoc estimators for the survival distribution and mean restricted survival time under different treatment policies. These estimators are consistent but not efficient, and do not include information from auxiliary covariates. In this article we derive estimators that are easy to compute and are more efficient than previous estimators. We also show how to improve efficiency further by taking into account additional information from auxiliary variables. Large sample properties of these estimators are derived and comparisons with other estimators are made using simulation. We apply our estimators to a leukemia clinical trial data set that motivated this study.

Granulocyte-macrophage colony-stimulating factor gene-transfected autologous tumor cell vaccine: focus[correction to fcous] on non-small-cell lung cancer

Traditionally, non-small-cell lung cancer (NSCLC) is not thought of as an immunosensitive malignancy. However, recent clinical results with GVAX, a granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced autologous tumor vaccine, may suggest otherwise. This review summarizes immune-induced activity caused by GM-CSF protein and GM-CSF gene-transfected vaccines. Initial indication of use for GM-CSF protein (sargramostim) was to improve neutrophil recovery following cytotoxic chemotherapy. However, several trials involving patients with hematologic malignancy demonstrated improvement in survival related to delayed disease progression in patients receiving sargramostim in combination with chemotherapy. Subsequently, others explored potential antitumor activity with sargramostim in a variety of trials. Results did not consistently demonstrate sufficient antitumor activity to justify routine use of sargramostim as an anticancer agent. Preclinical work with GM-CSF gene-transfected vaccines, however, did demonstrate significant activity, thereby justifying clinical investigation. Patients with metastatic NSCLC who had previously failed chemotherapy demonstrated response to GVAX (3 of 33 complete responses) and dose-related improvement in survival (471 days vs. 174 days).

Decision-making and quality of life in older adults with acute myeloid leukemia or advanced myelodysplastic syndrome

Older patients with acute myeloid leukemia (AML) and advanced myelodysplastic syndrome (aMDS) must decide between receiving intensive induction chemotherapy (IC) or nonintensive chemotherapy/best supportive care (NIC). Little information exists about what factors influence treatment decisions and what quality of life (QOL) is associated with treatment choices. We prospectively examined 43 patients 60 years or older who were interviewed at diagnosis and periodically over 1 year. IC choice was associated with younger age (66 vs 76 years, P=0.01) and AML diagnosis, but not with performance status, comorbidities, or QOL. In total, 63% of all patients reported not being offered other treatment options despite physician documentation of alternatives. Patient and physician estimates of cure differed significantly: 74% of patients estimated their chance of cure to be 50% or greater, yet for 89% of patients physician estimates of cure were 10% or less. IC patients experienced decreased QOL at 2 weeks, but rebounded to baseline and to NIC levels by 6 weeks. Initial QOL is not associated with treatment choice in older AML and aMDS patients. Regardless of treatment choice, patients report not being offered treatment options and overestimate their chances of cure. In IC patients, QOL decreases during hospitalization but rebounds after discharge.

Granulocyte-macrophage colony-stimulating factor to increase efficacy of mitoxantrone, etoposide and cytarabine in previously untreated elderly patients with acute myeloid leukaemia: a Swedish multicentre randomized trial

A total of 110 patients, aged 64 years or over, with de novo acute myeloid leukaemia (AML) and white blood cell counts <50 x 109/l were treated with 3 d of cytarabine 1 g/m2 twice daily, mitoxantrone 12 mg/m2 and etoposide 200 mg/m2, randomized with or without the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) 200 microg/m2. The primary aim was to evaluate the effect of GM-CSF on the remission rate. Secondary aims included comparison of duration of remission, survival and infectious complications and the impact of maintenance therapy with thioguanine. Complete remission (CR) was achieved by 64% of patients without GM-CSF, and by 65% of patients who received GM-CSF, the median remission duration was 13 vs. 6 months, the median overall survival (OS) was 14 vs. 9 months, the mean time to neutrophil recovery was 25 vs. 17 d (P = 0.03) and the number of positive blood cultures was 46 vs. 39 (P = 0.05) respectively. The impact of thioguanine remains unanswered since only 30 patients remained in CR after consolidation therapy. We conclude that induction therapy is feasible with acceptable toxicity in elderly patients with AML, albeit with a high relapse rate and short OS. GM-CSF prior to, and in combination with, induction treatment reduced the time to neutrophil recovery and the number of neutropenic septicaemia cases but did not improve the OS of AML in the elderly.

Acute myeloid leukemia

Advances in our understanding of the pathophysiology of acute myeloid leukemia (AML) have not yet led to major improvements in disease-free and overall survival of adults with this disease. Only about one-third of those between ages 18-60 who are diagnosed with AML can be cured; disease-free survival is rare and current therapy devastating in older adults. In this chapter, challenges in the management of the adult with AML are discussed, including ongoing questions concerning the optimal choice of induction and postremission therapy such as the rationale for and role of allogeneic and autologous stem cell transplantation in a variety of settings, the special considerations pertaining to the older patient, and the development of new, so-called targeted therapies. In Section I, Dr. Richard Stone reviews state-of the-art therapy in AML in the era of change from a morphological to a genetically based classification system. Questions being addressed in ongoing randomized cooperative group trials include anthracycline dose during induction, the efficacy of drug-resistance modulators, and the utility of pro-apoptotic agents such as the anti-bcl-2 antisense oligonucloetide. Developmental therapeutics in AML include drug resistance modulation, anti-angiogenic strategies, immunotherapy, and signal transduction-active agents, particularly the farnesyl transferase inhibitors as well as those molecules that inhibit the FLT3 tyrosine kinase, activated via mutation in 30% of patients. In Section II Dr. Margaret O'Donnell discusses the role of stem cell transplantation in AML. Several advances including expanded donor pools, the movement toward peripheral blood stem cell collection, newer immunosuppressive drugs and antifungals, and particularly the advent of nonmyeloablative transplant have made the allogeneic option more viable. The subset-specific role for high-dose chemotherapy with autologous stem cell support and/or for allogeneic transplant in AML patients in first remission is outlined. Although preconceived notions about the role of transplant abound, the clinical data supporting a risk-adapted approach are covered. Finally, guidance concerning the use of nonmyeloablative or reduced-intensity allogeneic transplantation is provided. In Section III Dr. Mikkael Sekeres reviews the approach to the older patient with AML. Unique biological and therapeutic considerations make AML in this age group a vastly different disease than that in younger adults. The outcome data, including the role of specific anthracylines, hematopoietic growth factors, and drug-resistance modulators, are summarized. Communicating with older adults with AML and their families regarding selection of the optimal treatment strategy, often a stark choice between induction chemotherapy and palliative care, is covered.

Farnesyltransferase inhibitors in hematologic malignancies: new horizons in therapy

Farnesyltransferase inhibitors (FTIs) are small-molecule inhibitors that selectively inhibit farnesylation of a number of intracellular substrate proteins such as Ras. Preclinical work has revealed their ability to effectively inhibit tumor growth across a wide range of malignant phenotypes. Many hematologic malignancies appear to be reasonable disease targets, in that they express relevant biologic targets, such as Ras, mitogen-activated protein kinase (MAPK), AKT, and others that may depend on farnesyl protein transferase (FTase) activity to promote proliferation and survival. A host of phase 1 trials have been recently launched to assess the applicability of FTIs in hematologic malignancies, many of which demonstrate effective enzyme target inhibition, low toxicity, and some clinical responses. As a result, phase 2 trials have been initiated in a variety of hematologic malignancies and disease settings to further validate clinical activity and to identify downstream signal transduction targets that may be modified by these agents. It is anticipated that these studies will serve to define the optimal roles of FTIs in patients with hematologic malignancies and provide insight into effective methods by which to combine FTIs with other agents.

Long-term outcome of autologous transplantation of peripheral blood progenitor cells as postremission management of adult acute myelogenous leukemia in first complete remission

In order to improve leukemia-free survival (LFS) without the treatment-related morbidity of allogeneic bone marrow transplantation or multiple prolonged cycles of consolidation chemotherapy, we evaluated the long-term outcome of autologous transplantation of peripheral blood progenitor cells (PBPCs) as postremission therapy in 129 patients aged 18-71 years (median 49 years) with newly diagnosed acute myelogenous leukemia (AML) in first complete remission (CR1). The median follow-up from remission for surviving patients was 62.2 months (range 3.7-127.9 months). A total of 57 patients were alive and leukemia free at the end of the study. The LFS and overall survival 5 years from remission were 40.2% (+/-9.2%) and 41.4% (+/-9.4%), respectively. The median LFS and overall survival are 17.3 and 23.3 months, respectively. Multivariate analysis identified age as the most significant predictor for both LFS and overall survival. Karyotype was also found to be predictive of outcome. Our results show that autologous transplantation of PBPC procured after a single cycle of high-dose cytarabine-based consolidation chemotherapy for a population of adult patients with AML in CR1 produces a high likelihood of long-term LFS, offering a state of clinical minimal residual disease for the investigation of future therapeutic approaches.

Pharmacology of cytotoxic agents: a helpful tool for building dose adjustment guidelines in the elderly

Aging is associated with multidimensional changes, including alterations in physiological functions, co-morbidities and poly-medications. These changes may lead to modifications in the absorption, distribution, metabolism and excretion of drugs. The lack of a scientific basis for optimal drug dosing in the elderly is a major problem. The development and validation of guidelines are therefore essential to improve treatment administration and monitoring in elderly patients. Even though it has been widely demonstrated that standard therapies used in adults may be of great benefit in the elderly, there may be a higher incidence of toxicity. This could be avoided by using dosage individualization based on a sound knowledge of the physiological factors implicated in the pharmacokinetic (PK) characteristics of the drugs administered and in their observed pharmacodynamic (PD) effects in each patient. The so-called "population modeling" approach renders such studies feasible by allowing the analysis of PK-PD relationships from sparse observational data.

Cost analyses of adjunct colony stimulating factors for older patients with acute myeloid leukaemia : can they improve clinical decision making?

Colony stimulating factors (CSF) have been shown to reduce the duration of neutropenia following intensive chemotherapy in a variety of settings, with many of these studies targeting older patients with leukaemia. We review the clinical and economic findings for use of growth factors for older adults with acute myelogenous leukaemia (AML). The cost analyses were based on the perspective of the third party payer. One study, conducted by the Southwest Oncology Group (SWOG) randomised 207 AML patients to receive granulocyte colony-stimulating factor (G-CSF) or placebo and found no significant difference in number of infections and in days of hospitalisation, 3 fewer days with an absolute neutrophil count <500 cells/microL with G-CSF, and an estimated incremental cost of only US 120 dollars with G-CSF over placebo (1997 costs). A second study, conducted by the Eastern Cooperative Oncology Group (ECOG), randomised 119 AML patients to receive granulocyte-macrophage colony-stimulating factor (GM-CSF) or placebo and found a reduction in severe infections, 4 fewer days with an absolute neutrophil count <500 cells/microL, no significant difference in the duration of hospitalisation, and estimated cost savings of US 2310 dollars with GM-CSF (1997 costs). These data may be useful to physicians faced with concerns over clinical and economic factors associated with CSF use as adjunct therapy for older persons with AML.

No benefit from adding GM-CSF to induction chemotherapy in transforming myelodysplastic syndromes: better outcome in patients with less proliferative disease

In this prospective randomized multicenter trial 93 patients, median age 72 years, with RAEB-t (n=25) and myelodysplastic syndrome (MDS)-AML (n=68) were allocated to a standard induction chemotherapy regimen (TAD 2+7) with or without addition of granulocyte-macrophage-CSF (GM-CSF). The overall complete remission (CR) rate was 43% with no difference between the arms. Median survival times for all patients, CR patients, and non-CR patients were 280, 550, and 100 days, respectively, with no difference between the arms. Response rates were significantly better in patients with serum lactate dehydrogenase (S-LDH) levels </=9.5 microkat/l, bone marrow cellularity </=70%, and WBC counts <4.0 x 10(9)/l, but S-LDH was the only variable independently associated with response by logistic regression analysis. Cox's regression analysis identified four significant prognostic factors for survival: bone marrow cellularity, S-LDH, cytogenetic risk group (International Prognostic Scoring System), and age. Only bone marrow cellularity (P=0.01) and S-LDH (P=0.0003) retained statistical significance in the log-rank test. Severe adverse events were significantly more common in the GM-TAD arm (P=0.01). Thus, addition of GM-CSF to chemotherapy showed no clinical benefit in terms of response but carried an increased risk for side effects. We present a clinically useful tool to predict response to chemotherapy and survival in elderly patients with transforming MDS, favoring patients with features of less proliferative disease.

Treatment concepts for elderly patients with acute myeloid leukemia

The majority of patients with acute myeloid leukemia (AML) are over 60 years of age at diagnosis. Unlike treatment options for younger adults, those for older patients are limited to non-myeloablative therapy, and many patients are not treatable because of poor performance status. In those who are treatable, long-term survival can be achieved using intensive induction and consolidation chemotherapy. Such curative treatment can be administered in about 70% of elderly patients with AML. In responding patients (up to 60%) the disease-free survival may be almost comparable to that of younger adults. However, treatment-related toxicity results in a higher mortality rate in the elderly patients. Moreover, aggressive chemotherapy cannot be used for 30% of the patients, due to their poor performance status. Currently, palliative cytoreductive treatment and supportive care are considered appropriate for these patients. Recently, however, targeting antileukemic antibodies and inhibitors of signal transduction have been introduced as promising new treatment options. The therapeutic efficiency and toxicity-profiles of these novel drugs are currently under investigation in clinical trials.

Timed-sequential chemotherapy with concomitant granulocyte colony-stimulating factor for newly diagnosed de novo acute myelogenous leukemia

EMA, consisting of etoposide, mitoxantrone, and cytarabine, is a timed-sequential chemotherapy (TSC) regimen and an efficacious option for induction treatment of acute myelogenous leukemia (AML). Hematopoietic growth factors (HGFs) have been shown to recruit leukemic blasts into cell cycle. We postulated the addition of granulocyte colony-stimulating factor (G-CSF) to EMA (EMA-G) might enhance treatment efficacy. EMA-G consisted of mitoxantrone on days 1-3, cytarabine on days 1-3 and 8-10, etoposide on days 8-10, and G-CSF from day 4 until absolute neutrophil count (ANC) >500/microl. In total, 28 patients were enrolled. All patients had newly diagnosed de novo AML. The median age was 42 years. Of the 27 patients with cytogenetic analysis, six had favorable karyotype, 18 intermediate karyotype, and three unfavorable karyotype. The median follow-up was 37.5 months. The median time for both ANC recovery and last platelet transfusion was 26 days. The toxicities associated with this regimen were no more than those expected with the standard chemotherapy. In all, 24 (86%) patients achieved complete remission (CR), three (11%) patients had no response, and one patient died within 24 h of induction therapy before response could be evaluated. Of the 24 patients who achieved CR, 22 received high-dose cytosine arabinoside and two received allogeneic bone marrow transplant as initial postremission therapy. For the whole cohort, the estimated 3-year survival rate was 67%. The median relapse-free survival was 30.5 months. We conclude that EMA-G regimen is a safe regimen and administration of G-CSF during and after induction treatment is not associated with prolongation of marrow aplasia or acceleration of leukemia relapse. It is efficacious for induction therapy for newly diagnosed de novo AML. A high CR rate can be achieved with only one course of this chemotherapy.

The detection of flow cytometric G-CSF receptor expression and it's effect on therapy in acute myeloid leukemia

The aim of this study was to evaluate G-CSF receptor (G-CSFr) expression on myeloid blasts, its prognostic significance and role in growth factor use and the safety and efficacy of G-CSF in the treatment of AML. Expression of G-CSFr, CD11a, CD11b, CD11c, CD13, CD33 and CD34 were analyzed with flow cytometry in 101 patients with AML aged 15-60 years. Results were reported as a percentage of positive cells. G-CSFr expression rate was found to be higher in M2 and M3 but lower in M5, M6 phenotypes, and in secondary leukemia. Patients were randomized for G-CSF use. Of 101 cases 51 received G-CSF. The overall remission rate was 68.7%. G-CSF use did not seem to have any effect on the remission rates. The median time to reach neutrophil counts > or = 1000/microliter in cases receiving G-CSF was 23 days, and 28 days in the control group (p < 0.01). G-CSF significantly reduced the number of febrile days (p < 0.01). Early and late relapses of 8 and 16 were observed during follow-up which was not effected by G-CSF use. In patients who were G-CSFr(+), G-CSF use did not alter overall survival rate. Univariate and multivariate analysis have revealed that not sex, G-CSF use or G-CSFr but age, FAB subtype and performance status at diagnosis were the important factors on both overall and disease free survival. We have demonstrated no beneficial effect of G-CSFr analysis on in vivo G-CSF use.

The role of myelopoietic growth factors in managing cancer in the elderly

More than 50% of all malignancies are diagnosed in patients aged > 65 years and most cancer-related deaths occur in this population. Misconceptions about prognosis and treatment contribute to the undertreatment of elderly cancer patients and consequent poor outcomes. Although older patients have been excluded from cancer treatment trials in the past, response rates to chemotherapy in a variety of common cancers in otherwise healthy elderly patients are comparable to those attained in younger patients. Lower functional reserve in many organ systems alters the pharmacokinetics of chemotherapeutic drugs as well as the patient's response to treatment-induced toxicity. Except for myelosuppression and mucositis, otherwise fit elderly cancer patients are not at significantly enhanced risk of toxicity to chemotherapy. Severe neutropenia and related infection are encountered much more frequently during the treatment of elderly as compared with younger cancer patients. These lead to treatment delays, dose reductions and higher hospitalisation rates. Myelopoietic growth factor support reduces myelosuppression and the associated risk of severe infection, thereby allowing delivery of chemotherapy at full dose intensity. Beneficial responses to granulocyte colony-stimulating factor (G-CSF; filgrastim) in elderly patients have been found in aggressive non-Hodgkin's lymphoma with standard cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) therapy and acute myeloid leukaemia (AML) during induction and consolidation chemotherapy. Granulocyte-macrophage colony-stimulating factor (GM-CSF; sargramostim) has been found to reduce myelosuppression in elderly AML patients receiving induction but not consolidation chemotherapy. These prophylactic treatments produce significant cost benefits because of the reduced hospitalisation and antibiotic use associated with neutropenia. To maximise positive outcomes, elderly patients should be included in clinical trials of new cancer agents. Since myelosuppression is the main risk factor for elderly patients undergoing chemotherapy, optimisation of growth factor support and the development of more effective and safer myelopoietic agents may improve success rates and reduce adverse events. Such information will lead to better management of cancer in older patients.

Elderly haematological patients with chemotherapy-induced febrile neutropenia have similar rates of infection and outcome to younger adults: a prospective study of risk-adapted therapy

We prospectively evaluated 131 consecutive episodes of fever and chemotherapy-induced neutropenia in 85 adults with haematological malignancies to determine whether older patients (aged < 60 years) have different causes of fever and outcome than younger adults (aged < 60 years). Patients were stratified into high-risk and low-risk groups according to previously published criteria. High-risk patients received ceftazidime plus amikacin and low-risk patients received ceftazidime alone. All patients were hospitalized until fever and neutropenia resolved. Ninety one high-risk episodes were documented: 56 occurring in older patients (mean age 69 years) and 35 in younger adults (mean age 45 years). Non-Hodkgin's lymphoma and acute myeloid leukaemia were the most frequent underlying neoplasias in both age groups. Intensity of chemotherapy was similar in both age groups. Mean neutrophil count at entry, median duration of neutropenia, rate of documented infection, incidence of bacteraemia, response to therapy, overall mortality and infectious mortality were similar in the two high-risk age subgroups. The elderly subgroup had a trend to have more Gram-negative infections and the younger patients more Gram-positive infections. In addition, 40 low-risk episodes were registered: 29 in elderly patients (mean age 68 years) and 11 in younger patients (mean age 44 years). Elderly low-risk patients had more concurrent diseases that younger ones (P = 0.124). Mean neutrophil count at entry, median duration of severe neutropenia and rate of response were similar in the two age subgroups. All low-risk patients survived. In conclusion, elderly haematological cancer patients with febrile neutropenia show similar rates of infection and outcome to younger ones.

Non-myeloablative allografting from human leucocyte antigen-identical sibling donors for treatment of acute myeloid leukaemia in first complete remission

Many patients with acute myeloid leukaemia (AML) in first complete remission (CR1) are ineligible for allogeneic transplantation as a result of age or medical problems other than leukaemia. Eighteen patients (median age 59 years, range 36-73 years) with de novo (n = 13) and secondary (n = 5) AML in morphological CR1, who were not candidates for conventional allografting, received non-myeloablative peripheral blood stem cell transplants from human leucocyte antigen identical sibling donors after conditioning with 2 Gy total body irradiation (TBI; n = 10) or 2 Gy TBI and 90 mg/m2 of fludarabine (n = 8). Postgrafting immunosuppression was with cyclosporine and mycophenolate mofetil. Two rejections were observed in patients not given fludarabine and one died with relapse. Overall, 10 patients died between 77 and 841 d, seven from relapse and three from non-relapse mortality (NRM). Day +100 NRM was 0% with a 1-year estimated NRM of 17%[95% confidence interval (CI) 0-35%]. The median follow-up among the eight survivors was 766 d (range, 188-1141 d). Seven of these eight survivors remain in complete remission (CR). One-year estimates of overall and progression-free survivals were 54% (95% CI 31-78%) and 42% (95% CI 19-66%) respectively. While follow-up is short, this analysis demonstrates that the procedure is sufficiently safe to be studied in a wider group of patients.

Impact of granulocyte colony-stimulating factor use during induction for acute myelogenous leukemia in children: a report from the Children's Cancer Group

PURPOSE

To determine whether granulocyte colony-stimulating factor (G-CSF) administered during acute myelogenous leukemia (AML) induction affects hematopoietic and nonhematopoietic toxicity, length and outcome of induction therapy, event-free survival, overall survival, and prognostic significance of the day 7 bone marrow.

PATIENTS AND METHODS

In Children's Cancer Group study 2891, patients were given intensively timed induction with G-CSF (n = 254) after accrual for the regimen without G-CSF (n = 258) was met.

RESULTS

Time to neutropenic recovery after induction courses 1 and 2 was significantly shorter for patients who received G-CSF. Times to platelet recovery were similar regardless of G-CSF use. Effects on incidence of grades 3 and 4 toxicities, infections, or fatal infections were not observed. Use of G-CSF reduced the median length of induction by 9 days and hospital stay by 6 days. Induction remission rates, overall survival, and event-free survival were similar with and without G-CSF. Day 7 bone marrow was prognostic of better long-term outcome. Patients with hypercellular day 7 marrow who received G-CSF had a higher remission rate and event-free survival than patients who did not receive G-CSF.

CONCLUSIONS

The incidence of severe toxic event and infection, induction remission rate, overall survival, and event-free survival were comparable regardless of G-CSF use. Use of G-CSF decreased neutropenia duration, hospital stay, and length of induction. Patients with hypercellular day 7 bone marrow who received G-CSF had an induction remission rate and event-free survival superior to those of patients who did not receive G-CSF.

Older adults with acute myeloid leukemia

Acute myeloid leukemia (AML) occurs most frequently in older adults, with a median age range from 65 to 70 years. Both the disease and its treatment are distinct from their counterparts in young patients. Herein we characterize the intrinsic biologic features of AML as it occurs in the older population, review currently available therapeutic approaches, and discuss therapeutic strategies in development.

Phase 3 study of the multidrug resistance modulator PSC-833 in previously untreated patients 60 years of age and older with acute myeloid leukemia: Cancer and Leukemia Group B Study 9720

The Cancer and Leukemia Group B conducted a phase 3 trial of the P-glycoprotein modulator PSC-833 in untreated acute myeloid leukemia patients aged 60 years and older. Patients were randomized to 1 of 2 regimens, with doses determined in a prior phase 1 study, consisting of cytarabine 100 mg/m2/d by 7-day infusion, with daunorubicin 60 mg/m2 and etoposide 100 mg/m2 daily for 3 days (ADE), or daunorubicin 40 mg/m2 and etoposide 60 mg/m2 for 3 days with PSC-833, 2.8 mg/kg over 2 hours, and then 10 mg/kg/d by 3-day infusion (ADEP). The ADEP arm was closed after randomization of 120 patients (61 to ADE and 59 to ADEP) because of excessive early mortality. Rates of complete remission, nonresponse, and death were 46%, 34%, and 20% for ADE, versus 39%, 17%, and 44% for ADEP (P = .008). Nevertheless, disease-free survival (median 7 vs 8 months; P = .38) and overall survival (approximately 33% alive at 1 year) did not differ and were similar to historical results. Although the number of patients was limited, ADE patients whose pretreatment cells exhibited PSC-833–modulated dye efflux in vitro (n = 22) had worse outcomes than those without efflux (n = 11) (complete remission, nonresponse, and death rates of 41%, 41%, and 18%, compared with 91%, 9%, and 0%; P = .03), but with ADEP outcomes were nearly identical. Moreover, for patients with PSC-833–modulated efflux, median disease-free survival was 5 months with ADE and 14 months with ADEP (P = .07). Further modulation trials in older patients must await the design of less-toxic regimens.

Persistent aplasia after chemotherapy for acute myeloid leukaemia treated with stem cell transplantation from a matched unrelated donor after dose-reduced conditioning

Persistent aplasia is a rare complication with poor prognosis after intensive chemotherapy for acute leukaemia. A 59-year-old man with acute myeloid leukaemia (AML), was treated after 186 d of chemotherapy-induced persistent aplasia with an allogeneic peripheral blood stem cell transplantation (PBSCT) from a matched unrelated donor (MUD) after dose-reduced conditioning. The patient remains in complete haematological remission more than 8.5 months after haematological recovery. We believe that this is the first reported case of treatment for chemotherapy-induced persistent aplasia with MUD-PBSCT after dose-reduced conditioning, a procedure that can be successfully performed even in elderly patients.

Progress in the treatment of acute myeloid leukaemia in adults

There has been important progress in the treatment of Acute Myeloid Leukaemia (AML) in patients under 60 years. A remission rate of 80% can be achieved by several schedules, and 40-45% of patients diagnosed will survive. It may still be possible to improve remission induction treatment eg by intensifying the Ara-C dose although may this only be detectable in an improved disease free survival. The is to reduce relapse. The risk main challenge is pre-determined by a number of powerful risk factors. In the experience of the MRC age, cytogenetics and clearance of blasts from the bone marrow after course 1. Using the later two in combination good risk patients (FAB M3, t(8;21) t(15;17) inv(16)) have a relapse risk of 32%. Poor risk (blasts >15% after course 1 or abnormalities of Chs 5 or 7, 3q- and complex changes have a relapse risk of 82%. All other cases are standard risk and ve a relapse risk of 56%. FLT3 mutations have been detected in about 25% of cases and provide additional negative predictive value overall and within each risk group. The assessment of the most effective consolidation treatment must be made taking into account the heterogeneity of the relapse risk. The MRC investigated the role of allo and autoBMT in addition to intensive chemotherapy. The data was analysis on an intent-to-treat or donor vs no donor basis. Although both types of transplant were able to reduce relapse overall and in all risk groups, there was an overall survival advantage only in standard risk patients. Since chemotherapy has improved since this study, there remains uncertainty about the benefit of transplant in all risk groups. Overall this experience has demonstrated that relapse can be reduced with more therapy. It is probable that the limits of conventional chemotherapy have been reached. The new AML15 trial will assess the value of adding the immunoconjugate (Mylotarg) to induction and/or chemotherapy. Improvements in older patients have been less detectable. MRC trials over the last 20 years show an improvement in remission rate (now 65%) but persistent poor survival (12% at 5 years). In the MRC AML11 Trial three induction schedules were compared (DAT vs ADE vs MAC) with DAT being superior. A comparison of a total of 3 vs 6 courses of treatment or the addition of interferon maintenance did not improve results. Newer approaches currently being assessed include resistance modulation; addition of immunoconjugate and minigrafts. New targets for treatment are emerging of which the most interesting is FLT3 inhibitors.

Acute myeloid leukemia

Through the hard work of a large number of investigators, the biology of acute myeloid leukemia (AML) is becoming increasingly well understood, and as a consequence, new therapeutic targets have been identified and new model systems have been developed for testing novel therapies. How these new therapies can be most effectively studied in the clinic and whether they will ultimately improve cure rates are questions of enormous importance. In this article, Dr. Jacob Rowe presents a summary of the current state-of-the-art therapy for adult AML. His contribution emphasizes the fact that AML is not a single disease, but a number of related diseases each distinguished by unique cytogenetic markers which in turn help determine the most appropriate treatment. Dr. Jerald Radich continues on this theme, emphasizing how these cytogenetic abnormalities, as well as other mutations, give rise to abnormal signal transduction and how these abnormal pathways may represent ideal targets for the development of new therapeutics. A third contribution by Dr. Frederick Appelbaum describes how AML might be made the target of immunologic attack. Specifically, strategies using antibody-based or cell-based immunotherapies are described including the use of unmodified antibodies, drug conjugates, radioimmunoconjugates, non-ablative allogeneic transplantation, T cell adoptive immunotherapy and AML vaccines. Finally, Dr. John Dick provides a review of the development of the NOD/SCID mouse model of human AML emphasizing both what it has taught us about the biology of the disease as well as how it can be used to test new therapies. Taken together, these reviews are meant to help us understand more about where we are in the treatment of AML, where we can go and how we might get there.

Treatment of acute myeloid leukemia: state-of-the-art and future directions

Despite major recent advances in the understanding of the molecular biology of the disease, the treatment of acute myeloid leukemia (AML) in adults remains challenging. For the 75% of AML patients older than 60 years, currently available treatments produce significant toxicity with poor overall response rates and survival. In younger patients, standard regimens using cytarabine and an anthracycline for induction followed by some form of intensive postremission therapy can produce response rates of 70% with 5-year relapse-free survival rates of 25% to 40%. Chromosomal analyses define three prognostic categories with favorable, intermediate, and unfavorable risk. In older adults, AML appears to be an intrinsically resistant disorder of proximal pluripotent hematopoietic stem cells. A variety of targeted therapies currently in development include modulators of MDR1-mediated drug resistance, immunotherapeutics, angiogenesis inhibitors, proapoptotic antisense oligonucleotides, and specific small molecule inhibitors of tyrosine kinase and farnesyltransferase. For example, oral farnesyltransferase inhibitors have demonstrated activity and tolerability in patients with refractory AML and are now in phase II testing. Such targeted therapeutics offer the promise of novel antileukemic activity combined with an improved therapeutic index.

Timed sequential chemotherapy with concomitant granulocyte colony-stimulating factor for high-risk acute myelogenous leukemia: a single arm clinical trial

BACKGROUND

The timed-sequential chemotherapy regimen consisting of etoposide, mitoxantrone and cytarabine (EMA) is an effective therapy for relapsed or refractory acute myelogenous leukemia (AML). We postulated that granulocyte colony-stimulating factor (G-CSF) might enhance the cytotoxicity of EMA by increasing the proportion of leukemic blasts in S-phase. We added G-CSF to EMA (EMA-G) for therapy of advanced high-risk AML patients.

METHODS

High-risk AML was defined as refractory, relapsed or secondary to either an antecedent hematologic disorder or exposure to cytotoxic agents. The patients were treated with one course of EMA-G consisting of mitoxantrone and cytarabine on days 1-3, and etoposide and cytarabine on days 8-10. G-CSF was started on day 4 and continued until absolute neutrophil count recovered.

RESULTS

Thirty patients were enrolled. The median age was 51 years (range, 25-75). Seventeen (61%) patients had unfavorable cytogenetic karyotypes. Twenty (69%) patients had secondary AML. Ten (34%) had relapsed disease. Four (14%) had refractory AML. Three (10%) patients died from febrile neutropenia and sepsis. Major non-hematologic toxicity included hyperbilirubimenia, renal insufficiency, mucositis, diarrhea, nausea and vomiting, skin rash. A complete remission was achieved in 13 (46%) patients. Median overall survival was 9 months (range, 0.5-66). Median relapse-free survival (RFS) for those who had a CR was 3 months (range, 0.5-63) with RFS censored at the time of allogeneic bone marrow transplantation or peripheral stem cell transplantation for 6 of the patients.

CONCLUSIONS

EMA-G is a safe and efficacious option for induction chemotherapy in advanced, high-risk AML patients. The activity of EMA may be increased if applied in patients with less advanced disease.

Cost-benefit analysis of granulocyte colony-stimulating factor in the management of elderly cancer patients

Health care costs continue to rise, and hospitalization represents the single largest component of direct medical costs associated with cancer care. Neutropenia and its complications including febrile neutropenia (FN) remain the major dose-limiting toxicity of systemic cancer chemotherapy. The risk of FN varies considerably across treatment regimens but appears to be significantly higher among elderly patients. The colony-stimulating factors (CSFs) have been used effectively in a variety of clinical settings to prevent or treat FN and to assist patients receiving dose-intensive chemotherapy with or without stem cell support. Several randomized controlled trials (RCTs) have demonstrated the clinical efficacy of the prophylactic use of CSFs. A recently presented meta-analysis of the available RCTs has confirmed the efficacy of prophylactic CSFs. The cost of these agents, along with their large-scale clinical use, has prompted a number of economic investigations. Economic models based on measures of resource utilization derived from RCTs have provided FN risk threshold estimates for the cost-saving use of prophylactic CSF. A number of important studies concerning the clinical and economic impact of these agents in elderly cancer patients have been reported during the past year. Continuing clinical and economic evaluation along with an updating of clinical practice guidelines especially related to elderly patients is recommended because of rapid technologic and clinical advances.

Less intense conditioning with fludarabine, cyclophosphamide, idarubicin and etoposide (FCIE) followed by allogeneic unselected peripheral blood stem cell transplantation in elderly patients with leukemia

The objective of this study was to assess toxicity and feasibility of achieving engraftment of allogeneic blood progenitor cells following nonmyeloablative conditioning according to the FCIE protocol (fludarabine 25 mg/m(2)/day, days -7 to -3; cyclophosphamide 200 mg/m(2)/day, days -7 to -3; idarubicin 12 mg/m(2)/day, days -7 to -5; etoposide 250 mg/m(2)/day, days -4 to -3) in elderly patients with leukemia. Eleven patients were included in the study: six patients with acute myeloid leukemia (AML) in complete remission (CR); three patients with refractory or relapsed AML; one patient with chronic myeloid leukemia; one patient with acute lymphoblastic leukemia. The median age of the patients was 62 years. All patients received blood progenitor cells from an HLA-identical sibling with 8.8 x 10(6) CD34(+) cells/kg (median; range 4.7 to 26.2 x 10(6)/kg) and 5.5 x 10(8) CD3(+)cells/kg (median; range 4.5 to 7.9 x 10(8)/kg). Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and three courses of methotrexate. The median duration of white blood cell counts <1 x 10(9)/l was 17 days and of platelet counts <50 x 10(9)/l 20 days. In two patients acute GVHD grade I occurred. Nine of 10 patients analyzed developed mixed chimerism. Of seven patients transplanted in CR, three remained in CR 19 to 31 months after transplantation. Three patients with refractory leukemia did not achieve CR, while the patient with relapsed AML achieved a 3rd CR. After a median follow-up time of 22 months, chronic GVHD was mild and limited. The data from this pilot study in elderly patients with leukemia show that the combination of primarily immunosuppressive (FC) and antileukemic (IE) drugs for nonmyeloablative conditioning has moderate nonhematological toxicity and allows engraftment of allogeneic blood progenitor cells.

Acute myeloid leukemia: treatment over 60

Undertreatment of older patients with acute myeloid leukemia (AML) can explain, in part, their inferior outcome when compared to that of younger patients. In agreement with the benefit seen by patients under age 60 from high-dose cytosine arabinoside (Ara-C), there are dose effects in the over 60s, in particular for daunorubicin, in induction treatment and for the duration of postremission treatment. The use of these effects can partly overcome the mostly unfavorable disease biology in older age AML, as expressed by the absence of favorable and the over-representation of adverse chromosomal abnormalities as well as the expression of drug resistance. We recommend an adequate dosage of 60 mg/m2 daunorubicin on 3 days in combination with standard dose Ara-C and 6-thioguanine given for induction and consolidation, and followed by a prolonged monthly maintenance chemotherapy for at least 1 year's duration. Further improvements in supportive care may help to deliver additional antileukemic cytotoxicity. As a novel approach, nonmyeloablative preparative regimens may open up the possibility of allogeneic transplantation for older patients with AML. Other new options like multidrug resistance modulators, antibody targeted therapies and molecular targeting 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 a diminished quality of life. This finding did not vary by age, under or over 60 years. As the median age in this disease is more than 60 years, the adequate management of AML in older patients remains the major challenge.

Acute myeloid leukemia: treatment of adults under 60 years

Current chemotherapy with advanced supportive care will enable 75-80% of acute myeloid leukemia patients aged 60 years or under to enter complete remission. Several regimens achieve broadly similar results. For patients who enter complete remission, the overall relapse risk is now 45-50%, but this is highly variable and is primarily determined by the biology of the disease. Cytogenetics are strongly influential in response to induction and consolidation with t(15:17), t(8:21) and inv(16) either occurring alone or with additional abnormalities having a relapse risk of about 30% and complex changes, abnormal 3q or abnormalities of chromosomes 5 and 7 resulting in a lower remission rate and a rapid relapse cumulating to 80%. FLT3 mutations occur in 25% of patients and are an independent predictor of relapse and, when combined with cytogenetics, adversely influence the prognosis in each cytogenetic risk group. Recent prospective collaborative group trials have endeavored to evaluate allogeneic and autologous bone marrow transplant against or in addition to consolidation chemotherapy. Suboptimal treatment delivery emerged as a problem. When the results were reported on an intention-to-treat basis, no overall survival advantage was consistently seen for either type of transplant. However, a significant reduction in risk of relapse was usually seen overall and within risk groups. Analysis within risk groups suggests that transplant is not indicated in good risk disease and continues to require evaluation in standard or poor risk patients. It is probable that traditional dose intensification has now reached its limits of tolerability, so new approaches will be required for further progress to be made. Modulation of chemoresistance mechanisms or immunologically directed chemotherapy represent immediate prospects for clinical study.

Estimation of survival distributions of treatment policies in two-stage randomization designs in clinical trials

Some clinical trials follow a design where patients are randomized to a primary therapy at entry followed by another randomization to maintenance therapy contingent upon disease remission. Ideally, analysis would allow different treatment policies, i.e., combinations of primary and maintenance therapy if specified up-front, to be compared. Standard practice is to conduct separate analyses for the primary and follow-up treatments, which does not address this issue directly. We propose consistent estimators for the survival distribution and mean restricted survival time for each treatment policy in such two-stage studies and derive large-sample properties. The methods are demonstrated on a leukemia clinical trial data set and through simulation.

Prognostic factors in elderly patients with acute myelogenous leukemia: a single center study in Japan

We retrospectively analyzed data of 47 patients aged 60 years or older, hospitalized in our institution with the diagnosis of acute myelogenous leukemia (AML), and searched for prognostic factors. Induction with anthracyclines significantly correlated with better complete remission (CR) rate (P = 0.0016) and overall survival (OS) (P < 0.001). Another factor significantly affecting CR rate was higher age (> 70 years) (P = 0.042). Therapy-non-related factors predictive for shorter OS in univariate analyses were age older than 70 years (P = 0.003), percentage of blasts in bone marrow more than 80% (P = 0.048), serum lactate dehydrogenase level higher than 250 U l(-1) (P = 0.032). In stepwise cox proportional hazard regression model, all the four factors predictive for poor OS remained to be independently and significantly prognostic for shorter OS. Only two patients receiving anthracyclines died within 30 days and the frequency was not different from that in patients not receiving anthracyclines. The use of anthracyclines as induction therapy is recommended even in the elderly patients.

The challenge of acute myeloid leukemia in older patients

Acute myeloid leukemia is a disease predominantly affecting older adults, with a median age at diagnosis of 65 years. Compared with younger adults or children with AML, older adults have a poor prognosis and represent a discrete population in terms of disease features, treatment-related complications, and overall outcome. Management of AML in this population often includes intensive, anthracycline-based chemotherapy, which can effect a 1.5- to 4-month survival advantage compared with nonintensive therapy but at a cost of early deaths, long length of hospital stay, and substantial transfusional support. Nonintensive therapy or palliative care remains an important option for many patients. Aggressive postremission therapy or the use of hematopoietic growth factor support does not appear to improve survival. Future directions include therapies targeted at immunomodulation, at angiogenesis, and in particular against intracellular signals that promote proliferation at the expense of differentiation.

Acute myeloid leukaemia (AML): treatment of the older patient

Undertreatment of the older patients with acute myeloid leukaemia (AML) can explain, in part, their inferior outcome when compared with that of younger patients. Corresponding to the benefit to patients under the age of 60 from high-dose Ara-C there are also dose effects in those over 60 years old, in particular for daunorubicin in the induction treatment, and for the quantity in terms of duration of postremission treatment. The use of these effects can partly overcome the mostly unfavourable disease biology seen in older age AML patients, which is expressed by the absence of favourable and the over-representation of adverse chromosomal abnormalities as well as by the expression of drug resistance. We recommend an adequate dosage of 60 mg/m(2)daunorubicin for 3 days in combination with standard dose Ara-C and 6-thioguanine given for induction and consolidation, followed by a prolonged monthly maintenance chemotherapy for a duration of at least 1 year. Further improvements in supportive care may help in delivering additional anti-leukaemic cytotoxicity. As a novel approach, non-myeloablative preparative regimens may open up the field of allogeneic transplantation for older patients with AML. Given that the actual median age in this disease is more than 60 years the management of older age AML remains as the major challenge.

Attempts to improve treatment outcomes in acute myeloid leukemia (AML) in older patients: the results of the United Kingdom Medical Research Council AML11 trial

In an attempt to improve induction chemotherapy for older patients with acute myeloid leukemia (AML),1314 patients were randomized to 1 of 3 induction treatments for 2 courses of DAT (daunorubicin, cytarabine, and thioguanine) 3 + 10, ADE (daunorubicin, cytarabine, and etoposide) 10 + 3 + 5, or MAC (mitoxantrone-cytarabine). The remission rate in the DAT arm was significantly better than ADE (62% vs 50%; P =.002) or MAC (62% vs 55%; P =.04). This benefit was seen in patients younger and older than 70 years. There were no differences between the induction schedules with respect to overall survival at 5 years (12% vs 8% vs 10%). A total of 226 patients were randomized to receive granulocyte colony-stimulating factor (G-CSF) or placebo as supportive care from day 8 after the end of treatment course 1. The remission rate or survival were not improved by G-CSF, although the median number of days to recover neutrophils to 1.0 x 10(9)/L was reduced by 5 days. Patients who entered remission (n = 371) were randomized to stop after a third course (DAT 2 + 7) or after 6 courses, ie, a subsequent COAP (cyclophosphamide, vincristine, cytarabine, and prednisolone), DAT 2 + 5, and COAP. The relapse risk (81% vs 73%), disease-free survival (16% vs 23%), and overall survival at 5 years (23% vs 22%) did not differ between the 3-course or 6-course arms. In addition to a treatment duration randomization, 362 patients were randomized to receive 12-month maintenance treatment with low-dose interferon, but no benefit was seen with respect to relapse risk, disease-free survival, or overall survival.

Effects of glycosylated recombinant human granulocyte colony-stimulating factor after high-dose cytarabine-based induction chemotherapy for adult acute myeloid leukaemia

The Australian Leukaemia Study Group (ALSG) investigated whether G-CSF would accelerate haemopoietic recovery after induction treatment for acute myeloid leukaemia (AML) intensified with high-dose cytarabine, and therefore improve response rates and survival. Patients were randomised to receive lenograstim (glycosylated recombinant human G-CSF) 5 microg per kg body weight subcutaneously daily from day 8 after starting chemotherapy, or no cytokine, following chemotherapy with cytarabine 3 g/m2 every 12 h on days 1, 3, 5, and 7, together with idarubicin 9 or 12 mg/m2 on days 1, 2, and 3, plus etoposide 75 mg/m2 on days 1 to 7 inclusive. Patients had untreated AML, and were aged 16 to 60 years. Overall, 54 evaluable patients were randomised to receive lenograstim and 58 to no cytokine. Patients in the lenograstim arm had a significantly shorter duration of neutropenia <0.5 x 10(9)/l compared to patients in the no cytokine arm (median 18 vs 22 days; P = 0.0005), and also shorter duration of total leucopenia <1.0 x 10(9)/l (17 vs 19 days; P = 0.0002), as well as a reduction in duration of treatment with therapeutic intravenous antibiotics (20 vs 24 days; P= 0.015) and a trend to reduced number of days with fever >38.0 degrees C (9 vs 12 days; P = 0.18). There were no differences between the two groups in platelet recovery, red cell or platelet transfusions, or non-haematological toxicities. For patients achieving CR after their first induction course, a reduction in the time to the start of the next course of therapy was observed in the lenograstim arm, from a median of 40.5 days to a median of 36 days (P = 0.082). The overall complete response rates to chemotherapy were similar, 81% in the lenograstim arm vs 75% for the no cytokine arm (P = 0.5), and there was no significant difference in the survival durations. We conclude that the granulopoietic stimulating effect of G-CSF is observed after induction therapy for AML intensified by high-dose cytarabine, resulting in an improvement in a number of clinically important parameters with no major adverse effects.

Therapeutic options for acute myelogenous leukemia

BACKGROUND

General therapeutic options for patients with acute myelogenous leukemia (AML) are reviewed and specific new therapies are described.

METHODS

Data in this review came from the published literature and the M. D. Anderson Cancer Center's acute leukemia database.

RESULTS

Outcome following standard therapy of AML is so variable that is best to speak of a range of outcomes determined by various prognostic factors. Therapy can (and usually does) fail because of treatment-induced mortality or (more usually) resistance to therapy. Performance status and age are the principal predictors of early death, whereas cytogenetics, a history of abnormal blood counts, and MDR1 expression are predictors of resistance. Using this information, physicians can categorize patients into those in whom 1) standard therapy is indicated, 2) either standard or investigational therapy is appropriate, and 3) investigational therapy is indicated. The majority of even newly diagnosed patients belong to Group 3. The availability of allogeneic or autologous transplantation does not alter this conclusion. Investigational therapies have been developed that are directed against the CD33 surface antigen, the multidrug-resistant MDR1 protein, and other targets. Because of the number of new therapies clinical research in AML should emphasize pilot trials rather than traditionally large Phase III studies.

CONCLUSIONS

Most patients with newly diagnosed AML should be offered investigational regimens.

Acute myeloid leukemia in the elderly: biology and therapeutic strategies

Age represents one of the most important adverse prognostic factors in acute myeloid leukemia (AML). The therapeutic results for patients older than 60 years accrued into clinical trials of intensive chemotherapy are largely unsatisfactory (complete remission rates rarely superior to 50-60%; median relapse-free survival usually less than 12 months). Because only 30-40% of elderly patients are actually entered into these trials, the overall failure of current treatments appear even more disappointing when considered in the context of the whole population of older individuals with AML. This appears primarily due to intrinsic differences in the biology of leukemia itself and to host-related factors (i.e. reduced tolerance to chemotherapy and comorbidity). AMLs of older subjects display several biological overlaps with secondary AMLs including multilineage involvement, phenotype, unfavorable cytogenetics and elevated activity of multidrug resistance genes. The clinical application of biologically-based prognostic factors may enable to separate patients who may actually benefit from aggressive chemotherapy from those who should be offered attenuated/palliative treatments or enrolled upfront into experimental trials of new drugs or biologic/immunologic treatments. This may hopefully result in a 'risk-adapted' strategy aimed at improving disease free survival and/or quality of life for patients with differing risk profiles.