High-dose cytarabine and daunorubicin as consolidation therapy for acute myeloid leukemia in first remission: long-term follow-up and results

Consolidation in AML: Abundant opinion and much unknown

Consolidation therapy forms the backbone of post-remission therapy for AML and is uniformly accepted as an integral part of therapy designed to achieve long-term survival. The need for post-remission therapy was initially described over four decades ago and has since undergone many variations in terms of dosage, number of cycles and intensity of therapy. There is much empiricism in the current understanding of consolidation therapy and much that has not been rigorously studied. This review will consider the many aspects of consolidation therapy, focusing on the number of cycles, differences between young and older adults, first and subsequent remission as well as therapy prior to an allogeneic transplant. Emphasis will be given to differentiate strategies that are clearly evidence-based from those that have been incorporated into standard of care while bypassing the need for rigorous data-driven approaches. Finally, consideration will be given to the current ability to assess the minimal measureable residual disease and the impact that this may have on therapeutic paradigms, including superseding many of the time-honored prognostic features.

Effect of postremission high dose cytarabine-based consolidation chemotherapy before allogenic stem cell transplantation in outcomes of acute myeloid leukemia patients

BACKGROUND AND AIM

This is a retrospective study aiming to investigate the effect of the number of high dose cytarabine-based chemotherapy (HiDAC) courses in patients with acute myeloid leukemia before allogenic stem cell transplantation (ASCT).

MATERIALS AND METHODS

A total of 110 patients with acute myeloid leukemia who received ASCT between 2001 and 2018 were included in the study.

RESULTS

Of the 110 patients, 25 (23%) patients received one course of HiDAC, 42 (38%) patients received two courses of HiDAC, 34 (31%) patients received three courses of HiDAC and 9 (8%) patients received four courses of HiDAC. Median follow-up for survivors was 71 months (range 4-186) for all patients. The 3-year overall survival for patients who received one course of HiDAC and patients who received more than one course of HiDAC were 49% and 70%, respectively (p = 0.29). The 3-year disease free survival (DFS) for patients who received one course of HiDAC and patients who received more than one course of HiDAC were 38% and 66%, respectively (p = 0.05). There was no statistically significant difference in OS between patients who received one or more than one consolidation chemotherapy. But there was nearly a statistically significant difference between patients who received one or more than one consolidation chemotherapy in DFS.

CONCLUSION

In conclusion, the administration of more than one consolidation chemotherapy may provide longer DFS, however the number of consolidation chemotherapy is not associated with statistically significant differences in overall outcomes.

Synergistic effects of phenylhexyl isothiocyanate and LY294002 on the PI3K/Akt signaling pathway in HL-60 cells

The aim of the present study was to investigate the synergistic effect of phenylhexyl isothiocyanate (PHI) and LY294002 [an inhibitor of phosphoinositide 3-kinase (PI3K)] on the PI3K/protein kinase B (Akt) signaling pathway, modulating histone acetylation, inhibiting cell viability and inducing apoptosis in HL-60 cells. The inhibition of HL-60 cell viability was monitored using an MTT assay. Cell apoptosis was measured using flow cytometry. Expression of acetylated histone H3 and histone H4, and the Akt signaling pathway proteins phosphorylated Akt (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR) and phosphorylated ribosomal protein S6 kinase (p-p70S6K) was detected using western blotting. The results of the present study identified that PHI and LY294002 were able to inhibit cell viability and induce cell apoptosis in HL-60 cells. The combination exhibited a synergistic effect on cell viability and apoptosis. PHI treatment led to an accumulation of acetylated histone H3 and histone H4, but LY294002 treatment had no effect on histone acetylation. However, LY294002 was identified to enhance the effect of PHI on histone acetylation in HL-60 cells. PHI and/or LY294002 were identified to dephosphorylate proteins in the PI3K/Akt signaling pathway, with a synergistic effect observed when used in combination. The results of the present study indicated that the combination of PHI and LY294002 may offer a novel therapeutic strategy for acute myeloid leukemia.

Outcomes of allogeneic stem cell transplantation among patients with acute myeloid leukemia presenting active disease: Experience of a single European Comprehensive Cancer Center

Introduction:

Allogeneic hematopoietic stem cell transplantation (ASCT) representes a potentially curative approach for patients with relapsed or refractory acute myeloid leukemia (AML). We report the outcome of relapsed/refractory AML patients treated with ASCT.

Method:

A retrospective cohort from 1994 to 2013 that included 61 patients with diagnosis of relapsed/refractory AML. Outcomes of interest were transplant-related mortality (TRM), incidence of acute and chronic graft-versus-host disease (GVHD), relapse incidence, progression-free survival (PFS) and overall survival (OS). Statistical significance was set at p<0.05.

Results:

The median age was 61 years (range 1 to 65). The cumulative incidence of 90 days, 1 year, and 3 years TRM were 60%, 26.7%, and 13.3%, respectively (p<0.001). The incidence of relapse was 21.7% at 1 year, 13% at 3 years, and 8.7% at 5 years. Median OS was estimated to be 8 months (95CI 3.266-12.734) and median PFS, 3 months (95CI 1.835-4.165).

Conclusion:

In our cohort, TRM in first years after ASCT remains considerable, but ASCT in this setting seems to be a good choice for AML patients with active disease. However, novel approaches are needed to reduce TRM and relapse in this set of patients.

miR-181a modulates acute myeloid leukemia susceptibility to natural killer cells

Although daunorubicin (DNR) is the most widely used anthracycline to treat acute myeloid leukemia (AML), resistance to this drug remains a critical problem. The aim of this study was to investigate the relationship between AML resistance to daunorubicin and susceptibility to natural killer (NK) cell-mediated cell lysis, and the putative expression of miRs. For this purpose, we used the parental AML cell lines U-937 and KG-1 and their equivalent resistant U937(R) and KG-1(R) cell lines. We demonstrate for the first time that the acquisition of resistance to DNR by the parental cell lines resulted in the acquisition of cross-resistance to NK cell-mediated cytotoxicity. miR microarray analysis revealed that this cross-resistance was associated with miR-181a downregulation and the subsequent regulation of MAP3K10 and MAP2K1 tyrosine kinases and the BCL^-2 (BCL^-2 and MCL^-1) family. Overexpression of miR-181a in AML blasts resulted in the attenuation of their resistance to DNR and to NK-cell-mediated killing. These data point to a determinant role of miR-181a in the sensitization of leukemic resistant cells to DNR and NK cells and suggest that miR-181a may provide a promising option for the treatment of immuno- and chemo-resistant blasts.

High-dose cytarabine as salvage therapy for relapsed or refractory acute myeloid leukemia--is more better or more of the same?

Cytarabine is the backbone of most chemotherapeutic regimens for acute myeloid leukemia (AML), yet the optimal dose for salvage therapy of refractory or relapsed AML (RR-AML) has not been established. Very high dose single-agent cytarabine at 36 g/m(2) (ARA-36) was previously shown to be effective and tolerable in RR-AML. In this retrospective analysis, we aim to describe the toxicity and efficacy of ARA-36 as salvage therapy for patients with AML who are primary refractory to intensive daunorubicin-containing induction or those relapsing after allogeneic stem cell transplant (alloSCT). Fifteen patients, median age 53 years, were included in the analysis. Six patients were treated for induction failure, one had resistant APL, and eight relapsed after alloSCT. Complete remission was achieved in 60% of patients. Surviving patients were followed for a median of 8.5 months. One-year overall survival was 54% (95% CI 30%-86%), and relapse rate from remission (n = 9) was 56%. Grade III/IV pulmonary, infectious, ocular and gastrointestinal toxicities occurred in 26%, 20%, 20% and 20% of patients respectively. Salvage therapy with ARA-36 regimen for RR-AML has considerable efficacy with manageable toxicity in patients with induction failure or post-transplant relapse. Overall survival in these high-risk patients still remains poor.

A novel treatment strategy targeting shugoshin 1 in hematological malignancies

Shugoshin 1 (SGOL1), a centromeric protein, plays an important role in mitosis. This study explored the levels of SGOL1 in hematological malignancies and found that SGOL1 was aberrantly expressed in various human leukemia cell lines (n=10, e.g., HL60, U937, MOLM-13, K562, EOL-1, etc.) and freshly isolated leukemia cells from individuals with acute myelogenous leukemia (AML, n=43, p<0.001) compared with bone marrow mononuclear cells isolated from healthy volunteers (n=9), as measured by real-time RT-PCR. Forced expression of SGOL1 in hematopoietic stem/progenitor cells (HSPCs) significantly increased colony numbers for CFU-M and CFU-GM compared with control vector transduced infected HSPCs, suggesting that SGOL1 might act as an oncogene in hematopoietic cells. In addition, we found that repression of SGOL1 by small interfering RNA (siRNA) slowed the proliferation of NB4, EOL-1 and U937 cells compared with the control siRNA transfected cells, in parallel with the appearance of precocious dissociation of centromeric cohesion and separation of sister chromatids in these cells. Furthermore, we found that repression of SGOL1 by siRNA accumulated EOL-1 and U937 cells in the G2/M phase of the cell cycle, in conjunction with up-regulation of the spindle checkpoint protein BubR1, followed by apoptosis via caspase pathways. Thus, SGOL1 might be a promising molecular target for treating individuals with AML.

Amonafide: a future in treatment of resistant and secondary acute myeloid leukemia?

Development of the novel topoisomerase II inhibitor, amonafide, began almost 40 years ago. The drug was selected for further investigation owing to evidence of marked antineoplastic efficacy in preclinical models of cancer. When its usefulness in the treatment of various solid malignancies proved limited, focus was shifted to establishing its use as an antileukemic agent, specifically against secondary and treatment-associated acute myeloid leukemia (AML). While Phase I and II studies gave rise to hopes that amonafide might hold the key to treating older patients, including those with multidrug resistant, cytogenetically unfavorable secondary and treatment-associated AML, when used in combination with cytarabine, it failed to demonstrate a survival advantage over standard-of-care therapy in randomized studies. This article will outline the development of amonafide from the laboratory to the bedside and discuss the potential place that this agent has in the current management of AML.

Is there a role for autologous stem cell transplantation for patients with acute myelogenous leukemia? A retrospective analysis

For patients with acute myelogenous leukemia (AML) who are unable to secure an acceptable HLA donor, the role of autologous stem cell transplantation (auto-SCT) has remained controversial. Its effectiveness remains unclear as, when analyzed on intention-to-treat strategies, a significant number do not undergo the procedure, whereas others seem to fail therapy from pretransplant recurrences. To improve our counseling to our patients on these 2 therapeutic options, we compared the outcome of patients in first remission of AML who actually underwent autologous or allogeneic transplantation. The choice for the type of graft was based on availability of HLA identical siblings. Patients received myeloablative conditioning followed by allogeneic or autologous cytokine mobilized peripheral blood stem cell transplantation. For prophylaxis of graft-versus-host disease (GVHD), grafts were incubated ex vivo with anti-CD52 antibodies and patients were prescribed cyclosporin until day 90. Patients were stratified by clinical and laboratory factors as well as cytogenetic risk. The endpoints were treatment-related mortality (TRM), disease-free survival (DFS), and overall survival (OS). The median presentation age for both transplant groups was 35 (14-60) years. Of the 112 consecutive patients achieving remission, autologous or allogeneic grafts were transplanted to 43 and 32 patients, respectively. There was no significant difference in the presentation clinical features, laboratory parameters, marrow morphology, or proportion of low and intermediate cytogenetic risk for both transplant options. Treatment mortality as well as relapse rate was similar (14% and 15%; 39% and 27%, respectively). At a median of 1609 and 1819 posttransplant days, 56% and 63% in each group survived. In univariate analysis performance status, cytogenetic risk, morphologic features of dysplasia, blast count, and lactate dehydrogenase (LDH) were significant factors for survival. Although for the entire group there was no difference in survival between both modalities, all patients with unfavorable cytogenetics receiving an autologous graft died of disease recurrence (3-year survival 35% versus 0%; P = .05). We conclude that patients with AML who have low or intermediate cytogenetic risk undergoing myeloablative conditioning followed by autologous or allogeneic T cell-depleted stem cell transplantation appeared to have similar outcome. However, those with unfavorable karyotype are unlikely to be cured with autologous grafts and are candidates for experimental modalities.

No Preferential Sensitivity of t(8;21) Acute Myeloid Leukemias to Cytosine Arabinoside in Vitro: Is Intensity of Therapy or High Dose Ara-C Crucial for Response?

Acute myeloid leukemia (AML) patients with core binding factor abnormalities [inv(16) or t(8;21)] have a relatively good prognosis, especially patients with inv(16) when treated with high-dose cytosine arabinoside (AraC) containing regimens, whereas in the case of t(8;21) evidences in favor of such regimen are contrasting. We previously demonstrated that blast cells from inv(16)-positive AML patients are characterized by an increased sensitivity to AraC with higher incorporation of 3H AraC into DNA and the increase of induced apoptosis in vitro. In the present study we tested the sensitivity of leukemic cells from 15 t(8;21)-positive AML patients to AraC and compared it with the results obtained from cells of 74 patients with inv(16), "intermediate" or "unfavourable" karyotype at diagnosis (for a total of 89 patients). The incorporation of 3H AraC into DNA in cells with t(8;21) was significantly lower than in cells with inv(16) (P = 0.02) or normal karyotype (P = 0.04). Interestingly, the incorporation of the drug into DNA in t(8;21) cells was similar to those with "unfavourable" karyotype. Furthermore, AraC induced apoptosis in t(8;21)-positive AML cells was not increased. These data suggest that the mechanism of response to chemotherapy for t(8;21)-positive cells is probably different then in AML cells with inv(16), underlining the possible importance for patients carrying the t(8;21) of repeated high-dose regimens and not necessarily of high-dose AraC based ones.

Clinical significance of Gata-1, Gata-2, EKLF, and c-MPL expression in acute myeloid leukemia

The aim of this study was to evaluate the biological correlation and prognostic impact of Gata-1, Gata-2, EKLF, and c-MPL transcript level in a group of 41 acute myeloid leukemia (AML) patients. Gata-1 overexpression was related to advanced age and a low percentage of bone marrow blasts and was associated with the expression of CD34 antigen and lymphoid T markers. The negative impact of Gata-1 expression on the probability of achieving complete remission has been confirmed. Gata-2 overexpression was associated with a low percentage of blasts in BM and males. Expression of c-MPL was associated with CD34+ AML and M2 FAB AML subtype. A higher expression of EKLF was found in secondary AML versus primary AML. Nevertheless, patients expressing EKLF had a longer overall survival and event free survival than those patients that did not express EKLF. Our study has identified expression of EKLF as a factor with a favorable impact on prognosis in AML.

Hematopoietic stem cell transplantation for core binding factor acute myeloid leukemia: t(8;21) and inv(16) represent different clinical outcomes

We analyzed 338 adult patients with acute myeloid leukemia (AML) with t(8;21) and inv(16) undergoing stem cell transplantation (SCT) who were registered in the Japan Society for Hematopoietic Cell Transplantation database. At 3 years, overall survival (OS) of patients with t(8;21) and inv(16) was 50% and 72%, respectively (P= .002). Although no difference was observed when restricted to allogeneic SCT in first complete remission (CR; 84% and 74%), OS of patients with t(8;21) and inv(16) undergoing allogeneic SCT in second or third CR (45% and 86% at 3 years; P= .008) was different. OS was not different between patients in first CR who received allogeneic SCT and those who received autologous SCT for both t(8;21) AML (84% vs 77%; P= .49) and inv(16) AML (74% vs 59%; P= .86). Patients with inv(16) not in CR did better after allogeneic SCT than those with t(8;21) (70% and 18%; P= .03). Patients with t(8;21) and inv(16) should be managed differently as to the application of SCT. SCT in first CR is not necessarily recommended for inv(16). For t(8;21) patients in first CR, a prospective trial is needed to clarify the significance of autologous SCT and allogeneic SCT over chemotherapy.

Low incidence of sepsis due to viridans streptococci in a ten-year retrospective study of pediatric acute myeloid leukemia

BACKGROUND

Infections remain an important cause of morbidity and mortality in children with acute myeloid leukemia (AML), and particularly viridans group streptococci (VGS) sepsis. The present study, conducted between 1993 and 2003 in children with AML, sought to assess the frequency and characteristics of infectious complications (ICs), the incidence of VGS sepsis, the interest of preventive decontamination, and a possible cytarabine dose-effect on the occurrence of ICs.

METHODS

Medical charts of 78 children treated according to the EORTC 58921 clinical trial were analyzed retrospectively. Patients were isolated in laminar air flow rooms, received non-absorbable gut decontamination, gum decontamination with vancomycin mouthwash, and trimethoprim-sulfamethoxasole. ICs were categorized as microbiologically documented infections (MDI), clinically documented infections (CDI), or fever of unknown origin (FUO).

RESULTS

Overall, 268 ICs occurred: 57.5% FUO, 8.5% CDI, and 34% MDI. Bloodstream infections occurred in 58 febrile episodes: Gram-positive bacteria represented 83% of the pathogens including 66.1% Staphylococcus species and 8.5% Streptococcus species (6.8% VGS), Gram-negative bacteria represented 13.5% of the pathogens and yeasts 3.5%. Five patients died of infection (6.4%). None died from bacterial infection and no case of VGS sepsis required intensive care. Invasive fungal infection was proven in four patients. Number of ICs was significantly different according to gum and gut decontamination status, and according to the cytarabine dose during the first intensification. No resistant strains were detected in spite of the use of local antibiotics.

CONCLUSION

The low rate of VGS and enterobacteriaceae sepsis was probably due to the effective decontamination. Our supportive care strategy could potentially help enhance overall survival in children with AML.

Results of 58872 and 58921 trials in acute myeloblastic leukemia and relative value of chemotherapy vs allogeneic bone marrow transplantation in first complete remission: the EORTC Children Leukemia Group report

The first EORTC (European Organization of Research and Treatment of Cancer) acute myeloblastic leukemia (AML) pilot study (58872) was conducted between January 1988 and December 1991. Out of 108 patients, 78% achieved complete remission (CR), and event-free survival (EFS) and survival rates (s.e., %) at 7 years were 40 (5) and 51% (6%), respectively. It indicated that mitoxantrone could be substituted for conventional anthracyclines in the treatment of childhood AML without inducing cardiotoxicity. The aim of the next EORTC 58921 trial was to compare the efficacy and toxicity of idarubicin vs mitoxantrone in initial chemotherapy courses, further therapy consisting of allogeneic bone marrow transplantation (alloBMT) in patients with an HLA-compatible sibling donor or chemotherapy in patients without a donor. Out of 177 patients, recruited between October 1992 and December 2002, 81% reached CR. Overall 7-year EFS and survival rates were 49 (4) and 62% (4%), respectively. Out of 145 patients who received the first intensification, 39 had a sibling donor. In patients with or without a donor, the 7-year disease-free survival (DFS) rate was 63 (8) and 57% (5%) and the 7-year survival rate was 78 (7) and 65% (5%), respectively. Patients with favorable, intermediate and unfavorable cytogenetic features had a 5-year EFS rate of 57, 45 and 45% and a 5-year survival rate of 89, 67 and 53%, respectively.

Treatment and long-term results in children with acute myeloid leukaemia treated according to the AIEOP AML protocols

Since 1982, four consecutive studies on childhood acute myeloid leukaemia (AML) (namely LAM-82, -87, -87M and -92) have been conducted in Italy by the Associazione Italiana di Ematologia e Oncologia Pediatrica (AIEOP) group. The induction therapy of the first three studies consisted of daunorubicin and cytarabine structured in a 3+7 backbone. In the most recent protocol (LAM92), patients received two induction courses including idarubicin, cytarabine and etoposide. Patients with acute promyelocytic leukaemia (20% of diagnoses) were included in LAM-87 and 87M studies. Postremissional therapy significantly changed over time, with an ever-increasing role given to stem cell transplantation (SCT). The long-term outcome of patients enrolled in the LAM-82, 87 and 87M studies was comparable, whereas that of children treated according to LAM-92 study was significantly better (P<0.005). Either allogeneic or autologous SCT was employed as consolidation therapy in more than 75% of cases enrolled in this latter study. Patients enrolled in the LAM-92 study were stratified in standard and high-risk groups with different outcome (67 vs 47%, respectively, P=0.04). Altogether, the results obtained in these four studies have permitted a progressive refinement of treatment, contributing to the structure of the ongoing LAM-2002 protocol that stratifies patients according to the presence of definite genetic anomalies and response to induction therapy.

Drug therapy for acute myeloid leukemia

Although improvement in outcomes has occurred in younger adults with acute myeloid leukemia (AML) during the past 4 decades, progress in older adults has been much less conspicuous, if at all. Approximately 50% to 75% of adults with AML achieve complete remission (CR) with cytarabine and an anthracycline such as daunorubicin or idarubicin or the anthracenedione mitoxantrone. However, only approximately 20% to 30% of the patients enjoy long-term disease survival. Various postremission strategies have been explored to eliminate minimal residual disease. The optimal dose, schedule, and number of cycles of postremission chemotherapy for most patients are not known. A variety of prognostic factors can predict outcome and include the karyotype of the leukemic cells and the presence of transmembrane transporter proteins, which extrude certain chemotherapy agents from the cell and confer multidrug resistance and mutations in or over expressions of specific genes such as WT1, CEBPA, BAX and the ratio of BCL2 to BAX, BAALC, EVI1, KIT, and FLT3. Most recently, insights into the molecular pathogenesis of AML have led to the development of more specific targeted agents and have ushered in an exciting new era of antileukemia therapy. Such agents include the immunoconjugate gemtuzumab ozogamicin, multidrug resistance inhibitors, farnesyl transferase inhibitors, histone deacetylase and proteosome inhibitors, antiangiogenesis agents, Fms-like tyrosine kinase 3 (FLT3) inhibitors, and apoptosis inhibitors.

Disposition of liposomal daunorubicin during cotreatment with cytarabine in patients with leukaemia

OBJECTIVE

To investigate the pharmacokinetics and pharmacodynamics of liposomal daunorubicin (DaunoXome) 80 or 100 mg/m(2) on days 1, 2 and 3 coadministered with standard or high-dose cytarabine to patients with poor-risk acute leukaemia.

DESIGN

Unblinded pharmacokinetic-pharmacodynamic study.

PARTICIPANTS

Twenty-three adult patients with acute leukaemia.

METHODS

Blood, bone marrow and urine samples were collected at appropriate intervals on days 1-6. Total daunorubicin and daunorubicinol concentrations in plasma, bone marrow, peripheral blood cells and urine were measured by high performance liquid chromatography.

RESULTS

Liposomal daunorubicin exhibited a markedly different pharmacokinetic behaviour from the free drug due to a slow distribution of the liposomal moiety into the body. The ratio of area under the concentration-time curve (AUC) for metabolite to parent drug was lower for liposomal daunorubicin than for free daunorubicin, mainly due to higher concentrations of the parent drug in plasma, whereas daunorubicinol exposure was more or less comparable, if not higher. After liposomal daunorubicin at both 80 and 100 mg/m(2), total daunorubicin concentrations in leukaemic cells were at least similar to those observed for free daunorubicin, and significant accumulation was also observed in bone marrow blast cells. Nineteen of 23 patients obtained a complete remission, although 13 had P-glycoprotein-overexpressing blast cells. Grade 3-4 mucositis was found only in three patients with very high AUCs for total daunorubicin and daunorubicinol.

CONCLUSIONS

Liposomal daunorubicin at both 80 and 100 mg/m(2) in combination with cytarabine may represent a valid treatment for high-risk acute leukaemia. Liposomal daunorubicin may be helpful in overcoming multidrug resistance, since it shows significant accumulation into tumour target cells, irrespective of P-glycoprotein expression. The tolerability profile suggests that toxicity may be related to exposure to both the parent drug and the metabolite.

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.

Diagnosis, treatment, and nursing care of acute leukemia

OBJECTIVE

To review the clinical presentation, current methods of diagnosis and classification, treatment modalities, and novel treatment approaches of acute myelogenous and lymphoblastic leukemia.

DATA SOURCES

Professional journals, web sites, and books.

CONCLUSION

The incidence of acute leukemia is increasing. As the population ages, it is anticipated that an even greater number will be diagnosed with this malignancy. The development of monoclonal antibodies, the recognition of the benefit of graft versus leukemia effect, and targeted therapies have improved overall survival rates. Still, age remains a significant prognostic variable. More research is needed to improve both the quality and the quantity of life for these patients.

IMPLICATIONS FOR NURSING PRACTICE

Nurses must understand the rationale and implications of each phase of treatment to educate patients, administer treatments, manage side effects, and provide support throughout the continuum of care.

Comparison of allogeneic stem cell transplantation, high-dose cytarabine, and autologous peripheral stem cell transplantation as postremission treatment in patients with de novo acute myelogenous leukemia

BACKGROUND

Postremission therapy is critical in maintaining complete remission (CR) in patients with de novo acute myelogenous leukemia (AML). The aim of this trial was to compare allogeneic stem cell transplantation (SCT), high-dose cytarabine (ara-C; HiDAC), and autologous SCT as postremission therapy in patients with de novo AML.

METHODS

One hundred twenty patients age </= 60 years with previously untreated AML (non-M3) and a performance status score of </= 2 received induction therapy with 3 days of idarubicin and 7 days of ara-C (IA). Patients in CR received one course of HiDAC. Subsequently, patients age </= 50 years with available HLA-compatible donors were assigned to receive allogeneic SCT; patients with "favorable" cytogenetics received a second course of HiDAC; and all others were randomized to a second course of HiDAC or autologous SCT.

RESULTS

The IA combination induced CR in 99 patients (82.5%). With a median follow-up of 43 months (range, 18-64 years), the 3-year survival and failure-free survival (FFS) rates were 47% and 45%, respectively. The factors associated with longer survival were those identified for CR (i.e., age and cytogenetics). Forty-nine patients (49%) received the assigned postremission therapy. Fifteen patients underwent allogeneic SCT. Nineteen patients underwent autologous SCT and 15 patients received a second course of HiDAC, after randomization. In the allogeneic SCT group, both the 3-year survival and the FFS rates were 73%. In the autologous SCT and HiDAC groups, the 3-year survival rates were 58% and 46%, respectively (P = 0.80), and the 3-year FFS rates were 42% and 33%, respectively (P = 0.83).

CONCLUSIONS

The three postremission treatment groups had comparable survival. Allogeneic SCT is associated with a prolonged FFS.

High-dose cytarabine as consolidation treatment for patients with acute myeloid leukemia with t(8;21)

Seventeen patients affected by acute myeloid leukemia (AML) with t(8;21) were prospectively programmed to receive three courses of high-dose cytarabine (HDARA-C) as post-remission therapy. The median age was 39 years and in all cases t(8;21) was the only karyotypic abnormality. Complete remission (CR) was achieved in 14 out of 17 cases (82%) and, after first consolidation with NOVIA regimen (intermediate dose ARA-C plus mitoxantrone), all patients received the three planned courses of HDARA-C (3g/m(2) q12h on days 1, 3, 5). There were two documented infections, while all patients experienced fever of unknown origin (FUO). Nonhematological toxicity was mild. Thirteen out of 14 patients are in continuous CR after a median follow-up of 44 months. One patient relapsed at 16 months and, following CR2 achievement, underwent allogeneic transplantation; he died 3 months later while in CR from acute graft versus host disease (GVHD). Survival at 5 years is projected at 79%. Our data confirm the efficacy of repeated courses of HDARAC for patients with t(8;21) AML.

Age and cytogenetics as predictors of event free survival in patients with acute non-lymphocytic leukemia receiving high dose cytosine arabinoside and daunorubicin as consolidation chemotherapy

Between 1991 and 1999, 67 patients with acute non-lymphocytic leukemia (ANLL) in complete remission received high dose cytarabine (HiDAC) 3 gm/m2 q12h x 12 doses followed by daunorubicin 45 mg/m2/day x 3 days as consolidation therapy. Five year actuarial event free survival (EFS) was 34% +/- 6%. Age was significantly associated with EFS. EFS was 60% +/- 15% in patients age 20 to 29, 48% +/- 16% in patients age 30 to 39, 23% +/- 10% in patients age 40 to 49, 31% +/- 11% in patients age 50 to 59, and 0% in patients age > or = 60. Contrary to other reports which have used different HiDAC regimens, we found no relationship between cytogenetics and EFS. Cytogenetics were defined as favorable risk: t(8;21), inv (16), and del (16); neutral risk: normal or t(15;17); and unfavorable risk: any abnormality not included in favorable risk or neutral risk. EFS was 29% +/- 17% in patients with favorable cytogenetics, 37% +/- 14% in patients with neutral cytogenetics, and 31% +/- 12% in patients with unfavorable cytogenetics. These differences were not statistically significant. Because of the successful use of allogeneic transplantation at relapse in patients with matched related donors, five year actuarial survival (S) in this series was 40% +/- 6%. Five year actuarial survival was 57% +/- 9% for patients age < or = 44 and 25% +/- 8% for patients age > or = 45. This difference is statistically significant, p < .025. Clinicians should be cautious about making clinical decisions regarding consolidation therapy of ANLL on the basis of the presence or absence of cytogenetic abnormalities as the importance of cytogenetics may depend on the specific therapy which is employed.

Transplantation of IL-2-mobilized autologous peripheral blood progenitor cells for adults with acute myelogenous leukemia in first remission

In order to improve leukemia-free survival we evaluated the feasibility and efficacy of autologous transplantation of interleukin-2 (IL-2)-mobilized peripheral blood progenitor cells for adult patients with acute myelogenous leukemia in first remission. Forty-nine consecutive patients (median age 49, range 21-70) with acute myelogenous leukemia in first remission were enrolled on a study of high-dose cytarabine/mitoxantrone consolidation chemotherapy with post-recovery IL-2 used as a method of in vivo purging for the purpose of autologous peripheral blood progenitor cell transplantation. A median of 2.08 x 10(6) CD34+ peripheral blood progenitor cells/kg were infused 1 day after preparative conditioning with 11.25 Gy total body irradiation and cyclophosphamide (120 mg/kg). Forty-one patients received myeloablative chemoradiotherapy followed by the infusion of IL-2-mobilized autologous peripheral blood progenitor cells. The median times to both neutrophil and platelet recovery were 16 days (range, 2-43) and 23 days (8-318+ days), respectively. Twenty-seven patients remain alive with 24 in continued first complete remission. Median remission duration for all eligible patients is 8 months, and actuarial leukemia-free survival is 49+/-15%. The actuarial risk of relapse is 43+/-16%. Toxicity of autologous peripheral blood progenitor cell transplant included treatment-related death in three patients and serious organ toxicity in 12. Advanced age was a negative prognostic factor for leukemia-free survival. Results were compared to an age-matched historical control treated with autologous transplantation of chemotherapy-mobilized progenitor cells; no significant difference in favor of IL-2 mobilization could be demonstrated. Our results demonstrate that autologous transplantation of IL-2-mobilized peripheral blood progenitor cells is feasible in an unselected population of adult patients with acute myelogenous leukemia in first remission with minimal toxicity but no clear evidence of benefit in leukemia-free survival.

High-dose cytosine arabinoside and idarubicin treatment of chronic myeloid leukemia in myeloid blast crisis

Chronic myeloid leukemia in myeloid blast crisis (CML-MBC) is highly resistant to standard induction chemotherapy regimens. Anecdotal results from previous clinical trials support the concept of dose escalation in patients with CML-MBC. Eight patients with CML-MBC were treated with cytosine arabinoside (Ara-C) 1.5-3.0 g/m2 intravenously over 1 hr every 12 hr for 12 doses and idarubicin 12 mg/m2 intravenously daily for 3 days. Sixteen previous reports describing the use of Ara-C-based chemotherapy regimens in patients with CML-MBC were also reviewed. Our patients' median age was 62 years (range, 42-69 years). One patient achieved complete hematologic remission (95% confidence interval, 0.3%, 53%). The median survival for our patients was 7.3 months. These results were not different from previous published reports using Ara-C-based chemotherapy regimens to treat CML-MBC. In summary, the combination of high-dose Ara-C and idarubicin did not improve the overall prognosis of patients with CML-MBC. Innovative approaches need to be explored for this patient population.

Glutathione S-transferase polymorphisms and outcome of chemotherapy in childhood acute myeloid leukemia

PURPOSE

Glutathione S-transferase theta (GSTT1) and mu (GSTM1) genes are polymorphic, the genes being absent in approximately 15% and 50% of the population, respectively. Because glutathione S-transferases may be involved in the metabolism of chemotherapy drugs, we hypothesized that presence or absence of the genes may influence the outcome of treatment for childhood acute myeloid leukemia (AML).

PATIENTS AND METHODS

We genotyped GSTT1 and GSTM1 in 306 children with AML receiving chemotherapy on Children's Cancer Group therapeutic studies. Outcomes were compared in those with and without GSTT1 and GSTM1 genes.

RESULTS

Patients with the GSTT1-negative genotype had reduced survival compared with those with at least one GSTT1 allele (GSTT1 positive) (52% v 40% at 5 years; log-rank P =.05). A multivariate model of survival adjusted for age group, sex, WBC count, chloroma, CNS involvement, and French-American-British group confirmed the increased risk of death in the GSTT1-null cases (relative risk, AQ 1.6; P =.02). The frequency of death in remission was increased in GSTT1-negative cases compared with GSTT1-positive cases (24% v 12%, log-rank P =.05). The frequency of relapse from end of induction was similar in GSTT1-negative and GSTT1-positive cases (38% v 35%, log-rank P =.5).

CONCLUSION

Children who lacked GSTT1 had greater toxicity and reduced survival after chemotherapy for AML compared with children with at least one GSTT1 allele. If confirmed in further studies, GSTT1 genotype might be useful in selecting appropriate chemotherapy regimens for children with AML.

Intensive postremission chemotherapy in Taiwanese adults with acute myelogenous leukemia

Intensive postremission chemotherapy has produced disease-free survival comparable to that of bone marrow transplantation in patients with acute myelogenous leukemia (AML), but its efficacy was unknown in Taiwan. We assessed the efficacy of intensive postremission chemotherapy, consisting of high-dose arabinoside-C (HiDAC) with or without transplantation of peripheral blood stem cells, in 33 AML patients from a single institute in Taiwan. Toxic reactions, treatment outcome, prognostic factors, and the size of the peripheral blood stem-cell harvest after HiDAC were analyzed. After a median follow-up of 21 months, 18 patients remained in continuous complete remission. The actuarial leukemia-free survival at 4 years was 51%. Relapse occurred in 12 patients, at a median of 12 months after initial diagnosis. All 6 patients with acute promyelocytic leukemia remained disease free after HiDAC therapy. Age, sex, and number of remission-induction or intensive consolidation chemotherapy courses had no effect on the risk of relapse. Intensive postremission chemotherapy can effectively prolong the duration of remission in young (< 60 years of age) adults with AML.

In vitro tumor-pulsed or in vivo Flt3 ligand-generated dendritic cells provide protection against acute myelogenous leukemia in nontransplanted or syngeneic bone marrow-transplanted mice

To determine whether immune stimulation could reduce acute myelogenous leukemia (AML) lethality, dendritic cells (DCs) were pulsed with AML antigens and used as vaccines or generated in vivo by Flt3 ligand (Flt3L), a potent stimulator of DC and natural killer (NK) cell generation. Mice were then challenged with AML cells. The total number of splenic anti-AML cytotoxic T-lymphocyte precursors (CTLPs) present at the time of challenge was increased 1.9-fold and 16.4-fold by Flt3L or DC tumor vaccines, respectively. As compared with the 0% survival of controls, 63% or more of recipients of pulsed DCs or Flt3L survived long term. Mice given AML cells prior to DC vaccines or Flt3L had only a slight survival advantage versus non-treated controls. NK cells or NK cells and T cells were found to be involved in the antitumor responses of Flt3L or DCs, respectively. DC vaccines lead to long-term memory responses but Flt3L does not. Syngeneic bone marrow transplantation (BMT) recipients were analyzed beginning 2 months post-BMT. In contrast to the uniform lethality in BMT controls given AML cells, recipients of either Flt3L or DC vaccines had a significant increase in survival. The total number of splenic anti-AML CTLPs at the time of AML challenge in BMT controls was 40% of concurrently analyzed non-BMT controls. Flt3L or DC vaccines increased the total anti-AML CTLPs 1.4-fold and 6.8-fold, respectively. Neither approach was successful when initiated after AML challenge. It was concluded that DC vaccines and Flt3L administration can enhance an AML response in non-transplanted or syngeneic BMT mice but only when initiated prior to AML progression.

Molecular and clinical advances in core binding factor primary acute myeloid leukemia: a paradigm for translational research in malignant hematology

Clonal chromosomal abnormalities are the most important prognostic indicators in acute myeloid leukemia (AML). Recent advances in molecular biology have allowed structural and functional characterization of many of these genomic rearrangements and have provided evidence for their primary role in leukemogenesis. Two of the most prevalent cytogenetic subtypes of adult primary or de novo AML, t(8;21)(q22;q22) and inv(16)(p13q22), are characterized by disruption of the AML1(CBF alpha 2) gene at 21q22 and the CBF beta gene at 16q22, respectively. Both genes encode a subunit of core binding factor (CBF), a regulator of normal hematopoiesis. At the molecular level, t(8;21)(q22;q22) and inv(16)(p13q22) result in the creation of novel fusion genes, AML1/ETO and CBF beta/MYH11, whose structures and functions are being successfully characterized by in vitro studies and transgenic animal models. Detection of t(8;21)(q22;q22) or inv(16)(p13q22) in adult patients with primary AML is a favorable independent prognostic indicator for achievement of cure after intensive chemotherapy or bone marrow transplantation and may serve as a paradigm for risk-adapted treatment in AML. The purpose of this review is to summarize the recent advances in the molecular biology and clinical management of t(8;21)(q22;q22) and inv(16)(p13q22) primary AML, collectively referred to here as CBF AML.

Patients with t(8;21)(q22;q22) and acute myeloid leukemia have superior failure-free and overall survival when repetitive cycles of high-dose cytarabine are administered

PURPOSE

To examine the effect of single compared with repetitive (at least three) cycles of high-dose cytarabine after induction therapy for patients with acute myeloid leukemia (AML) who have the t(8;21)(q22;q22) karyotype.

PATIENTS AND METHODS

Patients entered onto the study had AML and t(8;21) and attained a complete remission on four successive Cancer and Leukemia Group B studies. In these studies, either > or = three cycles of high-dose cytarabine or one cycle of high-dose cytarabine was administered, followed by sequential cyclophosphamide/etoposide and mitoxantrone/diaziquone with or without filgrastim support. Outcomes of these two groups of t(8;21) patients were compared.

RESULTS

A total of 50 patients with centrally reviewed AML and t(8;21) were assigned to receive one (n = 29) or > or = three cycles (n = 21) of high-dose cytarabine as postinduction therapy. The clinical features of these two groups of patients were similar. Initial remission duration for t(8;21) patients assigned to one cycle of high-dose cytarabine was significantly inferior (P =.03), with 62% of patients experiencing relapse with a median failure-free survival of 10.5 months, compared with the group of patients who received > or = three cycles, in which only 19% experienced relapse and failure-free survival is estimated to be greater than 35 months. Furthermore, overall survival was also significantly compromised (P =.04) in patients assigned to one cycle of high-dose cytarabine, with 59% having died as a consequence of AML, compared with 24% of those who received > or = three cycles of high-dose cytarabine.

CONCLUSION

These data demonstrate that failure-free survival and overall survival of patients with t(8;21)(q22;q22) may be compromised by treatment approaches that do not include sequential high-dose cytarabine therapy.

Autologous bone marrow transplantation in acute leukemia

Autologous bone marrow transplantation can induce long-term LFS in 20% to 40% of patients with relapsed acute leukemia and should be considered as salvage therapy for patients who lack an HLA-matched donor and for patients over 45. Adult ALL patients and children with ALL in extramedullary relapse beyond second CR should receive alloBMT if at all possible. The role of ABMT in acute leukemia patients in first CR remains unclear despite randomized trials (Table 2). Because protocol deviations, early relapse, and inappropriately high treatment-related mortality unequally affected the ABMT cohort, and because recent randomized trials have used old purging methodologies, it is not possible to conclude that ABMT is not beneficial. More recent studies show that most patients are able to proceed with the intended ABMT and that modern purging may be associated with a treatment-related mortality rate of less then 5%. Immunomodulation and graft engineering uniquely suited to autologous progenitor cells indicate that ABMT should continue to be studied in the management of acute leukemia.

T-Cell–Depleted Allogeneic Bone Marrow Transplantation as Postremission Therapy for Acute Myelogenous Leukemia: Freedom From Relapse in the Absence of Graft-Versus-Host Disease

Thirty-one consecutive patients with acute myelogenous leukemia (AML) in first complete remission and 8 with AML in second complete remission received T cell–depleted allogeneic bone marrow transplants from HLA-identical sibling donors. Patients received myeloablative cytoreduction consisting of hyperfractionated total body irradiation, thiotepa, and cyclophosphamide. Those patients at risk for immune-mediated graft rejection received additional immune suppression with antithymocyte globulin and methylprednisolone in the early peritransplant period. Patients with AML who underwent allogeneic T-cell–depleted bone marrow transplantations (BMT) in first or second remission have achieved respective disease-free survival (DFS) probabilities of 77% (median follow-up at approximately 56 months) and 50% (median follow-up at approximately 48 months). Ten of 31 patients transplanted in first remission were ≥ 40 years old and have attained a DFS at 4 years of 70%. For patients with AML transplanted in first or second remission, the respective cause-specific probabilities of relapse were 3.2% or 12.5%, and those of nonleukemic mortality were 19.4% or 37.5%. There were no cases of immune-mediated graft rejection and no cases of grade II to IV acute graft-versus-host disease (GVHD). All survivors enjoy Karnofsky performance scores (KPS) of 100%, except 2 patients with KPS of 80% to 90%. T-cell–depleted allogeneic BMT can provide durable DFS together with an excellent performance status in the majority of patients with de novo AML. In addition, GVHD is not an obligatory correlate of the graft-versus-leukemia benefit or freedom from relapse afforded by allogeneic BMT administered as postremission therapy for AML. This study provides a basis for prospective comparison with other postremission therapies considered standard in the management of patients with this disease.

T-Cell–Depleted Allogeneic Bone Marrow Transplantation as Postremission Therapy for Acute Myelogenous Leukemia: Freedom From Relapse in the Absence of Graft-Versus-Host Disease

Thirty-one consecutive patients with acute myelogenous leukemia (AML) in first complete remission and 8 with AML in second complete remission received T cell–depleted allogeneic bone marrow transplants from HLA-identical sibling donors. Patients received myeloablative cytoreduction consisting of hyperfractionated total body irradiation, thiotepa, and cyclophosphamide. Those patients at risk for immune-mediated graft rejection received additional immune suppression with antithymocyte globulin and methylprednisolone in the early peritransplant period. Patients with AML who underwent allogeneic T-cell–depleted bone marrow transplantations (BMT) in first or second remission have achieved respective disease-free survival (DFS) probabilities of 77% (median follow-up at approximately 56 months) and 50% (median follow-up at approximately 48 months). Ten of 31 patients transplanted in first remission were ≥ 40 years old and have attained a DFS at 4 years of 70%. For patients with AML transplanted in first or second remission, the respective cause-specific probabilities of relapse were 3.2% or 12.5%, and those of nonleukemic mortality were 19.4% or 37.5%. There were no cases of immune-mediated graft rejection and no cases of grade II to IV acute graft-versus-host disease (GVHD). All survivors enjoy Karnofsky performance scores (KPS) of 100%, except 2 patients with KPS of 80% to 90%. T-cell–depleted allogeneic BMT can provide durable DFS together with an excellent performance status in the majority of patients with de novo AML. In addition, GVHD is not an obligatory correlate of the graft-versus-leukemia benefit or freedom from relapse afforded by allogeneic BMT administered as postremission therapy for AML. This study provides a basis for prospective comparison with other postremission therapies considered standard in the management of patients with this disease.

Intensified induction chemotherapy with high dose cytarabine and etoposide for acute myeloid leukemia: a review and updated results of the Australian Leukemia Study Group

Induction therapy of acute myeloid leukemia (AML) with standard dose chemotherapy will result in approximately 55-75% of patients achieving a complete remission (CR). Intensification of induction treatment with etoposide and high dose cytarabine does not alter the CR rate but appears to significantly improve the subsequent outcome. Updated results of the comparison of high dose cytarabine with daunorubicin and etoposide in induction (HIDAC-3-7) versus a standard dose combination (7-3-7) demonstrated a highly significant increase in relapse free survival, (RFS) on the high dose arm (p = 0.007) with RFS of 48% at 5 years with HIDAC-3-7 and 25% on 7-3-7. The high dose arm had a more modest survival advantage at 5 years of 33% compared with 25% on standard treatment, possibly because of a higher initial death rate with HIDAC-3-7. The improvement seen in patients with CR after high dose induction appear to parallel results obtained with post-remission therapies intensified with high dose cytarabine. These studies provide clinical evidence that a dose-response effect is present for cytarabine in AML. Intensified treatment is more toxic, gives more profound myelosuppression post-remission and has been shown to benefit younger patients only. Issues of patient selection and the optimal placement of intensification in the treatment sequence require further study. In the future, it is likely that remission duration may be a useful clinical tool to study the influence of new induction therapies on residual resistant leukemia.

Audit of practice in platelet refractoriness

OBJECTIVES

A significant number of patients become refractory to platelet transfusion and prompt investigation of the cause will encourage appropriate selection of platelet products.

METHODS

We surveyed haematologists to assess perceived practice concerning platelet refractoriness because of the high cost and limited availability of HLA-compatible platelets. Some 56 of 58 consultant haematologists participated.

RESULTS

Clinicians differed on their definition of platelet refractoriness, and non-immune factors were not considered as important as immune causes of platelet refractoriness. A working group, including an invited moderator, was established to produce guidelines on recommended practice for the management of platelet refractoriness. Re-audit after implementation of the guidelines showed that more patients receiving HLA-compatible platelets had been tested for HLA antibodies. There was a mean 50.9% reduction in the use of HLA-compatible platelets.

CONCLUSIONS

Increased testing for leucocyte and platelet antibodies resulted in reduced demand for and more selective use of HLA-compatible platelets, with no apparent increase in haemorrhagic complications.