The role of allogeneic transplantation in high-risk acute myelogenous leukemia

Pre-Transplant Serum Leptin Levels and Relapse of Acute Myeloid Leukemia after Allogeneic Transplantation

Weight loss and metabolic activity influence outcome after allogeneic stem cell transplantation (alloSCT). This study evaluates pre-conditioning Leptin, a peptide hormone involved in metabolism and immune homeostasis, as a prognostic factor for survival, relapse and non-relapse mortality (NRM) following alloSCT. Leptin serum levels prior to conditioning were determined in a cohort of patients transplanted for various hematologic malignancies (n = 524) and correlated retrospectively with clinical outcome. Findings related to patients with acute leukemia (AL) from this sample were validated in an independent cohort. Low pre-conditioning serum Leptin was an independent prognostic marker for increased risk of relapse (but not of NRM and overall mortality) following alloSCT for AL of intermediate and advanced stage (beyond first complete remission). Multivariate analysis revealed a hazard ratio (HR) for relapse of 0.75 per log2 increase (0.59–0.96, p = 0.020). This effect was similar in an independent validation cohort. Pre-conditioning serum Leptin was validated as a prognostic marker for early relapse by fitting the multivariate Cox model to the validation data. Pre-conditioning serum Leptin levels may serve as an independent prognostic marker for relapse following alloSCT in intermediate and advanced stage AL patients. Prospective studies are required to prove whether serum Leptin could be used for guiding nutritional intervention in patients with AL undergoing alloSCT.

Wernicke's Encephalopathyafter Allogeneic Stem Cell Transplantation

Wernicke's encephalopathy is an acute neuropsychiatric condition due to thiamine deficiency frequently associated with chronic alcohol abuse. We describe 2 cases of patients who experienced acute Wernicke's encephalopathy after allogeneic stem cell transplantation associated with the use of commercial total parental nutrition. Early diagnosis with magnetic resonance imaging and timely treatment with thiamine resulted in rapid resolution of clinical and radiological signs. In conclusion, the prolonged use of commercial total parental nutrition formulas must be supplemented with thiamine in the form of intramuscularly administered multivitamins.

The influence of pretransplantation conditioning on graft-vs.-leukemia effect in mice

OBJECTIVE

The therapeutic potential of allogeneic hematopoietic stem cell transplantation relies on the graft-vs.-leukemia (GVL) effect to eradicate residual tumor cells immunologically. The relationship of conditioning intensity to GVL effect was investigated.

MATERIALS AND METHODS

Lethally irradiated (either 900 or 1300 cGy) B6D2F1 (H-2(b/d)) recipients were transplanted from B6 (H-2(b)) donors. P815 or L1214 (H-2(d)) tumor cells were injected intravenously or subcutaneously on day 1 post-transplantation to generate a GVL model.

RESULTS

Tumors in allogeneic mice treated with 1300 cGy exhibited markedly delayed subcutaneous tumor growth in vivo as compared with mice treated with 900 cGy, while intravenous tumor growths were comparable between the two radiation doses. Serum levels of tumor necrosis factor-α or interferon-γ were similar and the percentages of donor T-cell proliferation or apoptosis early after hematopoietic stem cell transplantation were comparable. The numbers of CD8(+) T cells from recipients that received 1300 cGy were significantly elevated in skin and tumor tissues. CD62L(low) and CD44(high) CD8(+) T-cell fractions were also elevated in 1300 cGy. After the higher radiation dose, P815-specific interferon-γ responses of splenic CD8(+) T cells were markedly enhanced and the fractions of T cells of interferon-γ-producing T cells in tumor tissues but not in spleen were increased. The protein concentrations of chemokines in skin and tumor tissues were substantially elevated in 1300 cGy compared to 900 cGy.

CONCLUSIONS

The higher radiation dose (1300 vs. 900 cGy) resulted in significantly enhanced GVL effect against an extramedullary tumor and the alterations in effector T-cell trafficking into tumor tissue are the most likely mechanism.

Long-term outcomes in patients with high-risk myeloid malignancies following matched related donor hematopoietic cell transplantation with myeloablative conditioning of BU, etoposide and CY

Patients with high-risk or advanced myeloid malignancies have limited effective treatment options. These include high-dose therapy followed by allogeneic hematopoietic cell transplantation (HCT). We report a single-institution, long-term follow-up of 96 patients, median age 50 (range, 20-60) years, who received HLA-matched related HCT between 1992 and 2007. All patients were treated with a uniform preparatory regimen intended to enhance the widely used regimen of BU and CY that included: BU 16.0 mg/kg (days -8 to -5), etoposide 60 mg/kg (day -4), CY 60 mg/kg (day -2) with GVHD prophylaxis of CsA or FK506 and prednisone. Disease status at transplantation was high-risk AML (n=41), CML in second chronic phase or blast crisis (n=8), myelofibrosis and myeloproliferative disorders (n=8), and myelodysplasia (n=39). Thirty-six percent (n=35) of patients received BM whereas 64% (n=61) received G-CSF-mobilized PBPC. With a median follow-up of 5.6 years (range, 1.6-14.6 years) actuarial 5-year OS was 32% (95% CI 22-42) and 5-year EFS was 31% (95% CI 21-41). Relapse rate was 24% (95% CI 15-33) at 2 and 5 years. Nonrelapse mortality was 29% (95% CI 20-38) at day 100 and 38% (95% CI 29-47) at 1 year. Cumulative incidence of acute (grade II-IV) and extensive chronic GVHD was 27% (95% CI 18-36) and 29% (95% CI 18-40), respectively. There was no statistically significant difference in OS (31 vs 32%, P=0.89) or relapse rates (17 vs 28%, P=0.22) for recipients of BM vs PBPC, respectively. These results confirm that patients with high-risk or advanced myeloid malignancies can achieve long-term survival following myeloablative allogeneic HCT with aggressive conditioning.

Successful cell-mediated cytokine-activated immunotherapy for relapsed acute myeloid leukemia after hematopoietic stem cell transplantation

Acute myeloid leukemia (AML) is an extremely aggressive disease with a high relapse rate even after allogeneic hematopoietic stem cell transplantation (HSCT). We report the successful outcome of cell-mediated cytokine-activated immunotherapy in a high-risk pediatric AML patient who relapsed shortly after allogeneic HSCT. Donor lymphocyte infusion along with interferon induced a graft-versus-leukemia effect, presenting as a reversible episode of graft-versus-host disease, which led to stable complete donor chimerism and total eradication of AML for over 24 months, at the time of this report. The curative potential of immunotherapy in hematological malignancies is discussed.

Deletion 15q as the sole abnormality in acute myeloid leukemia: report of three cases and review of the literature

Deletions within the long arm of chromosome 15, a recurrent abnormality in myeloid malignancies, have been reported previously as a sole abnormality in only eight cases of acute myeloid leukemia (AML). We describe three new cases of AML with this abnormality, all adult women (age, 41-66 years). Two cases were acute myelomonocytic leukemia (FAB AML-M4), and one was acute myeloblastic leukemia with maturation (FAB AML-M2). The deletion was identified at initial diagnosis in one patient and at relapse in the other two. Although all received aggressive therapy, their survival was short. Taken together with the eight previously reported cases, we conclude that deletions in chromosome 15 are associated with AML, both in cases that arise de novo or in the setting of a myeloproliferative disorder or myelodysplastic syndrome. These cases often show features of myelomonocytic or monocytic differentiation. The prognosis is poor, with survival similar to other AML cases with unfavorable cytogenetic changes.

Hematopoietic stem cell transplantation in adults with acute myeloid leukemia

Hematopoietic stem cell transplantation (HSCT) is an integral part of the treatment of many patients with acute myeloid leukemia (AML). Despite extensive study, the appropriate role and timing of allogeneic and autologous transplantation in AML are poorly defined. This review critically analyzes the extensive literature, focusing on the recent advances, and provides practical recommendations for the use of HSCT in AML.

MicroRNA signatures associated with cytogenetics and prognosis in acute myeloid leukemia

MicroRNAs (miRNAs) are small RNAs of 19 to 25 nucleotides that are negative regulators of gene expression. To determine whether miRNAs are associated with cytogenetic abnormalities and clinical features in acute myeloid leukemia (AML), we evaluated the miRNA expression of CD34(+) cells and 122 untreated adult AML cases using a microarray platform. After background subtraction and normalization using a set of housekeeping genes, data were analyzed using Significance Analysis of Microarrays. An independent set of 60 untreated AML patients was used to validate the outcome signatures using real-time polymerase chain reaction. We identified several miRNAs differentially expressed between CD34(+) normal cells and the AML samples. miRNA expression was also closely associated with selected cytogenetic and molecular abnormalities, such as t(11q23), isolated trisomy 8, and FLT3-ITD mutations. Furthermore, patients with high expression of miR-191 and miR-199a had significantly worse overall and event-free survival than AML patients with low expression (overall survival: miR-191, P = .03; and miR-199a, P = .001, Cox regression). In conclusion, miRNA expression in AML is closely associated with cytogenetics and FLT3-ITD mutations. A small subset of miRNAs is correlated with survival.

Anti-leukaemic role of acute GvHD after unrelated haematopoietic stem cell transplantation in intermediate- to high-risk acute myelogenous leukaemia

Little is known about the role of acute GvHD (aGvHD) based on the concept of graft-versus-leukaemia effect (GVLE) after unrelated donor haematopoietic stem cell transplantation (uHSCT). We evaluated 67 uHSCTs performed with multinational unrelated donors for patients with AML. The median follow-up duration was 18 months (range 7-61). The majority of patients had intermediate- or high-risk cytogenetic findings. The conditioning regimen for most patients consisted of cyclophosphamide plus total body irradiation (n=56) with our standard GvHD prophylaxis containing tacrolimus plus a short course of methotrexate. The incidence of aGvHD and chronic GvHD was 50 and 52%, respectively. Eight patients (12%) have relapsed to date. The estimated overall disease-free survival (DFS) rate at 5 years was 67%. Notably fewer relapses were seen when aGvHD developed (P=0.008). Specifically, high-risk AML patients had a much lower relapse rate when they developed aGvHD (P=0.01), compared with the intermediate-risk group. Therefore, the development of aGvHD after uHSCT in AML patients is closely related to a lower relapse rate, probably in association with GVLE.

Reduced intensity conditioning allows for up-front allogeneic hematopoietic stem cell transplantation after cytoreductive induction therapy in newly-diagnosed high-risk acute myeloid leukemia

There is substantial need to improve the outcome of patients with high-risk acute myeloid leukemia (AML). The clinical trial reported here investigated a new approach of up-front allogeneic hematopoietic stem cell transplantation (HSCT), provided a median of 40 days (range 22-74) after diagnosis, in twenty-six consecutive patients with newly-diagnosed high-risk AML characterized by poor-risk cytogenetics (n = 19) or inadequate blast clearance by induction chemotherapy (IC, n = 7). The median age was 49 years (range 17-68). During IC-induced aplasia after the 1st (n = 11) or 2nd (n = 15) cycle, patients received allogeneic peripheral blood stem cells (PBSC) from related (n = 11) or unrelated (n = 15) donors following a fludarabine-based reduced-intensity regimen. Seventeen patients were not in remission before HSCT with a median marrow blast count of 34% (range 6-70). All patients achieved rapid engraftment and went into remission with complete myeloid and lymphatic chimerism. Grades II to IV acute GvHD occurred in 14 (56%) and extensive chronic GvHD was documented in 8 (35%) patients. The probability of disease-free survival was 61% with only three patients relapsing 5, 6 and 7 months after transplantation, respectively. Up-front allogeneic HSCT as part of primary induction therapy seems to be an effective strategy in high-risk AML patients and warrants further investigation.

Elevated serum insulin-like growth factor binding protein-2 is associated with a high relapse risk after hematopoietic stem cell transplantation in childhood AML

Insulin-like growth factor binding protein (IGFBP)-2 has mitogenic effects in normal and neoplastic cells. The purpose of this study is to examine the diagnostic and prognostic significance of elevated IGFBP-2 levels in children with AML after hematopoietic stem cell transplantation (HSCT) at relapse and continuous complete remission (CCR). In 27 children with AML (mean age 13.6+/-5.3 years; patients in remission n=15 with relapse n=12) serum parameters of IGFBP-2, IGFBP-3, IGF-I and IGF-II were analyzed up to 18 months after HSCT by RIA. AML-patients with evidence of relapse demonstrated a continuous increase of IGFBP-2 levels during the follow-up. At day 100 after HSCT, IGFBP-2 concentrations were significantly higher in patients with relapse than in children without relapse (7.4+/-4.0 standard deviation score (SDS) vs 3.9+/-1.7 SDS; P=0.01). Serum IGFBP-2 was identified as an independent factor for the prediction of relapse. Furthermore, the probability of relapse-free survival (RFS) in patients with IGFBP-2 >4.5 SDS at day 100 after HSCT was 31% compared to patients with IGFBP-2 <4.5 SDS was 72% (P=0.004). Patients with IGFBP-2 concentration up to 4.5 SDS more likely developed a relapse and had a poorer outcome. Identification of these patients allows a more individualized and aggressive adjuvant treatment and follow-up.

Long-term results in children with AML: NOPHO-AML Study Group--report of three consecutive trials

In all, 447 children with acute myeloid leukaemia (AML) have been treated on three consecutive NOPHO studies from July 1984 to December 2001. NOPHO-AML 84 was of moderate intensity with an induction of three courses of cytarabine, 6-thioguanine and doxorubicin followed by four consolidation courses with high-dose cytarabine. The 5-year event-free survival (EFS), disease free survival (DFS) and overall survival (OS) were 29, 37 and 38%. NOPHO-AML 88 was of high intensity with the addition of etoposide and mitoxantrone in selected courses during induction and consolidation. The interval between the induction courses should be as short as possible, that is, time intensity was introduced. The 5-year EFS, DFS and OS were 41, 48 and 46%. In NOPHO-AML 93, the treatment was stratified according to response to first induction course. The protocol utilised the same induction blocks as NOPHO-AML 88, but after the first block, children with a hypoplastic, nonleukaemic bone marrow were allowed to recover before the second block. Consolidation was identical with NOPHO-AML 88. The 5-year EFS, DFS and OS in NOPHO-AML 93 were 48, 52 and 65%. The new NOPHO-AML protocol has been based on experiences from previous protocols with stratification of patients with regard to in vivo response and specific cytogenetic aberrations.

The role of reduced intensity conditioning allogeneic stem cell transplantation in patients with acute myeloid leukemia: a donor vs no donor comparison

Using a genetic randomization through a 'donor' vs 'no donor' comparison, the aim of this analysis was to assess the real benefit of reduced intensity conditioning allogeneic stem cell transplantation (RIC-allo-SCT) among 95 adult high-risk acute myeloid leukemia (AML) patients. In an 'intention-to-treat' analysis, leukemia-free survival (LFS) was significantly higher in the 'donor' group as compared to the 'no donor' group (P=0.01; 54 vs 30% at 4 years). The latter held true when restricting the analysis to the 25 patients who could actually receive the RIC-allo-SCT (P=0.001). Overall transplant-related mortality in the 'transplant' group was 12%, with overall survival (OS) being significantly higher in the 'transplant' group as compared to the 'no transplant' group (P=0.01). Also, in the 'intention-to-treat' analysis, OS was significantly higher in the 'donor' group as compared to the 'no donor' group (P=0.04). In the multivariate analysis, actual performance of RIC-allo-SCT (P=0.001; RR=4.0; 95% CI, 1.7-9.6) was the strongest factor significantly predictive of an improved LFS. We conclude that if a matched related donor is identified, RIC-allo-SCT should be proposed for AML patients not eligible for standard myeloablative allo-SCT.