Transplantation in first remission of acute myeloid leukemia

The role of gemtuzumab ozogamicin in acute leukaemia therapy

Gemtuzumab ozogamicin (GO) is an immunoconjugate that binds to CD33 on the surface of acute myeloid leukaemia (AML) blasts and, after internalisation, releases a cytotoxic drug, calicheamicin. GO is approved by the US Food and Drug Administration for the treatment of CD33-positive AML at first relapse in patients 60 years and older who are not candidates for other cytotoxic therapy. GO as a single agent has low antileukaemic activity. When given to patients meeting the criteria noted above, it produces a complete response (CR) rate of only 12%, with another 12% achieving CR with inadequate platelet recovery (CRp). The median survival of patients treated with GO monotherapy is 11.2 months. GO therapy at 9 mg/m(2) is complicated with hepatic veno-occlusive disease in 5-10% of patients, particularly prior to or following stem cell transplantation. GO at lower doses combined with chemotherapy as induction or postremission therapy is promising, however, and phase III trials are ongoing. GO is probably most active in acute promyelocytic leukaemia (APL). It is used for induction regimens in high-risk APL and for the elimination of minimal residual APL. Case reports suggest that GO also has activity in CD33-positive acute lymphoblastic leukaemia. In conclusion, single agent GO can induce responses in patients with CD33-positive AML in first recurrence. The future of GO is its use in combination with other cytotoxic agents. Ongoing clinical trials may better define the role of GO combinations, particularly in untreated AML.

Adult acute myeloid leukemia

Acute myeloid leukemia (AML) is a group of several different diseases, the treatment and outcome of which depend on several factors, including leukemia karyotype, patient age, and comorbid conditions. Despite advances in understanding the molecular biology of AML, its treatment remains challenging. Standard regimens using cytarabine and anthracyclines for induction followed by some form of postremission therapy produce response rates of 60% to 70%, with less than 20% of all patients achieving long-term disease-free survival. New therapies are emerging based on the definition of specific cytogenetic-molecular abnormalities. Such targeted therapies offer the promise of better antileukemic activity in adult AML.

Adverse impact of bone marrow transplantation on quality of life in acute myeloid leukaemia patients; analysis of the UK Medical Research Council AML 10 Trial

The increasing success of intensive consolidation chemotherapy (CCT) as an alternative to bone marrow transplant (BMT) in acute myeloid leukaemia (AML) necessitates comparison of the impact on quality of life (QoL) of these two treatment modalities. Most QoL studies following BMT involve small patient numbers and provide ambivalent results. The present study examines QoL in a large number of patients 1 year from the end of treatment within the United Kingdom Medical Research Council (UK MRC) AML10 trial of BMT versus CCT. Allogeneic-BMT (Allo-BMT) was observed to have an adverse impact on most QoL dimensions compared with Autologous-BMT (A-BMT) and CCT. More patients receiving BMT had mouth dryness problems and worse sexual and social relationships, professional and leisure activities than CCT patients. QoL in A-BMT patients was less impacted than Allo-BMT. Intention-to-treat analysis showed similar results. These results indicate that a reconsideration of treatment strategies is warranted, and that further, good prospective studies are needed to evaluate more clearly the effects of these treatments in long-term survivors.

Reassessing autotransplantation for acute myeloid leukaemia in first remission – a matched pair analysis of autologous marrow vs peripheral blood stem cells

The role of autologous stem cell transplantation in adult patients with acute myeloid leukaemia (AML) in first remission is unclear, yet it has become standard treatment for myeloma and this paper explores whether the source of transplanted stem cells may explain this paradox. In total, 57 patients from the Royal Marsden Hospital who received an unpurged bone marrow transplant (ABMT) were matched with 114 patients from the EBMT registry who had undergone peripheral blood stem cell transplantation (PBSCT). Patients were matched for karyotype, FAB type, remission-autograft interval and age. In the PBSCT group, haematopoietic recovery was significantly faster and nonrelapse mortality at 4 years was significantly lower (13 vs 1%, P=0.04). The relapse rate and overall survival at 4 years (20 vs 31% and 77 vs 63%) were also better with PBSCT, although the differences were not statistically significant. Autografting should be reassessed in a randomised trial for first remission AML patients using peripheral blood as a source of stem cells rather than bone marrow.

Autologous stem cell transplantation for acute myelogenous leukemia in first complete remission: a 6-year follow-up study of 101 patients from a single institution

The objective of the study was to assess the long-term outcome and impact of stem cell source in patients with acute myelogenous leukemia (AML) who received ASCT in first complete remission (CR). A total of 101 patients (median age 46 years) were included in the study. Cytogenetic categories distribution was: favorable: 18%, intermediate: 42%, and unfavorable: 7%. More than one induction course was needed for CR in 21% of patients. In all, 78% of patients had received at least one course of high-dose ara-C before autologous stem cell transplantation (ASCT). Bone marrow (n=58) or peripheral blood stem cells (PBSC) (n=43) transplantation was performed at a median of 3.5 months from CR. Hematologic recovery and hospitalization duration were significantly reduced in the PBSC group. No toxic death was recorded in this group. The median follow-up of survivors is 67 months (range: 15-183). The 6-year survival, disease-free survival (DFS), and relapse probabilities are 44%, 38%, and 54%, respectively. The presence of a favorable karyotype and the use of PBSC are independently associated to better survival, and DFS by multivariate analysis. Our results confirm that long-term DFS can be achieved with high-dose chemotherapy and ASCT in patients with AML. They show that use of PBSC is associated to very low mortality rate and acceptable morbidity and contributes to an improvement of autotransplant results.

Survival-weighted health profile for long-term survivors of acute myelogenous leukemia

The objective of this study was to use survival-weighted psychometric scores (SWPS) to construct a 'health profile' for long-term survivors of acute myelogenous leukemia (AML). The study cohort included all patients who had been diagnosed and treated in our institution from 1985 to 1999 and achieved complete remission after standard chemotherapy (n = 259). One hundred and four patients were interviewed by the European Organization for the Research and Treatment of Cancer (EORTC)-QLQ-C30 questionnaire and the brief form of World Health Organization quality of life questionnaire (WHOQOL-BREF) to estimate the quality of life (QOL) function of the cohort. Forty-one patients underwent bone marrow transplantation (BMT) as consolidation or salvage therapy; 63 received chemotherapy alone. SWPS for every functioning domain and symptom item was obtained by direct integration of the mean QOL function with the survival function of the cohort. A Monte Carlo method was used to extrapolate the life-long SWPS beyond the follow-up limit. The mean scores of EORTC-QLQ-C30 and WHOQOL-BREF did not differ significantly between patients who received BMT or those who received chemotherapy only (p > 0.01). In mean SWPS, patients who received BMT had significantly (p < 0.01) better SWPS in all of the functioning domains and symptom items of EORTC-QLQ-C30 and all four domains of WHOQOL-BREF. However, when the life-long extrapolation of SWPS was made, these differences diminished in global health and several symptom items of EORTC-QLQ-C30 as well as in the social and environmental domains of WHOQOL-BREF. Patients' perspective on QOL may be domain-specific and may evolve over time. SWPS may be useful to evaluate the efficacy of different treatment strategies for AML. Confirmation of the relative merit of BMT vs. chemotherapy alone from prospective studies is needed.

The value of allogeneic bone marrow transplant in patients with acute myeloid leukaemia at differing risk of relapse: results of the UK MRC AML 10 trial

Patients under 55 years in the United Kingdom Medical Research Council Acute Myeloid Leukaemia 10 trial who entered complete remission were tissue typed (n = 1063). Four hundred and nineteen had a matched sibling donor and 644 had no match. When compared on a donor versus no donor basis the relapse risk was reduced in the donor arm (36%vs 52%; P = 0.001) and the disease-free survival (DFS) improved (50%vs 42%; P = 0.01), but overall survival (OS) was not different (55%vs 50%; P = 0.1). Sixty-one per cent of patients with a donor underwent transplantation. When patients were subdivided into risk groups based on cytogenetics alone or with the addition of blast response to course 1, a reduction in relapse risk was seen in all risk groups and in three age cohorts (0-14, 15-34 and 35+ years). Significant benefit in DFS was only seen in the intermediate-risk cytogenetic group (50%vs 39%; P = 0.004). The OS benefit was only seen in intermediate-risk patients (55%vs 44%; P = 0.02). The reduction in relapse risk in good-risk patients was attributable to patients with t(15;17) and not to patients with t(8;21) or inv(16). Allogeneic transplantation given after intensive chemotherapy was able to reduce relapse in all risk and age groups. However, due to the competing effects of procedural mortality and an inferior response to chemotherapy if relapse does occur, there was a survival advantage only in patients of intermediate risk. This trial found no survival advantage in children, patients over 35 years or good-risk disease.

Evaluation of the clinical relevance of the expression and function of P-glycoprotein, multidrug resistance protein and lung resistance protein in patients with primary acute myelogenous leukemia

The multidrug resistance (MDR) transporter-proteins P-glycoprotein (Pgp), multidrug resistance protein (MRP) and lung resistance protein (LRP) have been associated with treatment failure. The aim of this study was to investigate prospectively the clinical significance of expression and function of the MDR proteins, considering other prognostic factors, such as age, immunophenotype, and cytogenetics. Mononuclear cells of peripheral blood or bone marrow from 61 patients with de novo acute myelogenous leukemia (AML) were analyzed. The monoclonal antibodies JSB1, MRPm6 and LRP56 were used for expression studies. Accumulation and retention studies were performed using the substrates Daunorubicin, Calcein-AM, Rhodamine-123 and DiOC(2) in the presence or absence of the modifiers Verapamil, Genistein, Probenecid, BIBW22S and PSC833. Induction treatment consisted of a 3+7 combination of Ida/Ara-C for patients < or = 60 years of age and a 3+5 Ida/VP-16 combination per OS for patients >60. MDR function was expressed as the ratio of mean fluorescence intensity substrate in the presence of modifier over the substrate alone (resistance index, RI). Patients with advanced age, low CD15 expression and high RI for accumulation of DiOC(2) in the presence of BIBW22S had significantly lower complete remission (CR) rates. No factor was prognostic for event-free survival analysis, which was limited to remitters only. Overall survival was shorter in patients with advanced age, poor prognosis cytogenetics, high CD7 expression, and high RI for Daunorubicin efflux modulated by Verapamil. These results suggest that MDR transporter-proteins have a limited role in the treatment failure of patients treated with Idarubicin-based regimens.

The clinical significance of cytogenetic abnormalities in acute myeloid leukaemia

During the last three decades it has become apparent that the majority of cases of acute myeloid leukaemia (AML) are characterized by at least one of a variety of recurrent chromosomal abnormalities. These changes have been found in many instances to correlate closely with distinct morphological features and clinical characteristics, the molecular basis of which is becoming increasingly understood. Furthermore, diagnostic karyotype has been shown to be a key determinant of outcome in AML, with mounting evidence to support the notion that cytogenetic analysis can serve to identify biologically distinct subsets of disease that demand tailored therapeutic approaches. This has led to a rising trend towards routine cytogenetic and molecular characterization of newly diagnosed acute leukaemia, providing a framework for treatment stratification.

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.

Granulocyte colony-stimulating factor after intensive consolidation chemotherapy in acute myeloid leukemia: results of a randomized trial of the Groupe Ouest-Est Leucémies Aigues Myeloblastiques

PURPOSE

Ten years after the first clinical studies, the clinical impact of myeloid growth factors in acute myeloid leukemia is still unclear. One of the objectives of the Groupe Ouest-Est Leucémies Aigues Myeloblastiques (GOELAM) 2 trial was to evaluate the benefit of granulocyte colony-stimulating factor (GCSF) given only after the two courses of intensive consolidation chemotherapy (ICC) used to maintain complete remission (CR).

PATIENTS AND METHODS

One hundred ninety-four patients who were in CR after induction treatment were randomly assigned to receive G-CSF (100 patients) or no G-CSF (94 patients) after two courses of ICC (ICC 1, high-dose cytarabine plus mitoxantrone; ICC 2, amsacrine plus etoposide). G-CSF (filgrastim) was administered from the day after chemotherapy until granulocyte recovery at a daily dose of 5 microg/kg.

RESULTS

In the G-CSF group, the median duration of neutropenia (< 0.5 x 10(9)/L) was dramatically reduced, both after ICC 1 (12 v 19 days, P <.001) and after ICC 2 (20 v 28 days, P <.001). The median duration of hospitalization was also significantly shorter in the G-CSF group (24 v 27 days after ICC 1, P <.001; 29 v 34 days after ICC 2, P <. 001). The median duration of intravenous antibiotics was significantly reduced after ICC 1 and ICC 2, and the median duration of antifungal therapy was significantly reduced after ICC 1. However, the incidence of microbiologically documented infections, the toxic death rate, the 2-year disease-free survival, and the 2-year overall survival were not affected by G-CSF administration. Moreover, the median interval between ICC1 and ICC2 was reduced by only 2 days, and the number of patients undergoing ICC2 was not increased in the G-CSF arm.

CONCLUSION

G-CSF should be administered routinely after ICC to reduce the duration of neutropenia and hospitalization. However, G-CSF did not seem to significantly increase the feasibility of this two-course program or modify overall outcome.