Impact of the expression of P glycoprotein,the multidrug resistance-related protein,bcl-2, mutant p53, and heat shock protein 27 on response to induction therapy and long-term survival in patients with de novo acute myeloid leukemia

OBJECTIVE: Resistance to chemotherapy-induced apoptosis and a multidrug-resistance phenotype is the major problem in the treatment of acute myeloid leukemia (AML). PATIENTS AND METHODS: We recently demonstrated that the coexpression of at least two proteins, including P glycoprotein, multidrug resistance-related protein, bcl-2 (flow cytometry), p53 (luminometric immunoassay), and heat shock protein 27 (Western blotting), was predictive for response to induction therapy in de novo AML comparing leukemic blasts of 20 responders with 20 nonresponders. After long-term follow-up, we now present our evaluation on the prognostic significance of these proteins in leukemic blasts of 124 untreated AML patients with regard to the probability of remission (PoR) and overall survival (OS). RESULTS: Analyzing leukemic blasts obtained from bone marrow samples, we found that no single protein significantly correlated with PoR or OS. In contrast, the coexpression of at least two of these proteins was predictive for reduced OS in univariate as well as multivariate analysis. Although we could not identify any particular protein combination predictive for reduced OS, those patients with no or only one protein expressed in their leukemic blasts had a survival probability of 48% in contrast to 24% in those patients with the coexpression of two or more proteins. Among the clinical markers, only response to chemotherapy had a significant effect on OS and age was of prognostic relevance for PoR. CONCLUSION: We conclude that overexpression of only one protein possibly involved in resistance, is not sufficient to influence the prognosis for long-term survival in AML, whereas the expression of more than one protein is predictive for reduced OS. Protein combination seems to be individually different, and targeting only one protein in further clinical trials may not help to overcome multifactorial resistance.     

De novo acute myeloid leukemia with 20–29% blasts is less aggressive than acute myeloid leukemia with ≥30% blasts in older adults: a Bone Marrow Pathology Group study

It is controversial whether acute myeloid leukemia (AML) patients with 20–29% bone marrow (BM) blasts, formerly referred to as refractory anemia with excess blasts in transformation (RAEBT), should be considered AML or myelodysplastic syndrome (MDS) for the purposes of treatment and prognostication. We retrospectively studied 571 de novo AML in patients aged > 50 years, including 142 RAEBT and 429 with ≥30% blasts (AML30), as well as 151 patients with 10–19% BM blasts (RAEB2). RAEBT patients were older and had lower white blood count, but higher hemoglobin, platelet count, and karyotype risk scores compared to AML30, while these features were similar to RAEB2. FLT3 and NPM1 mutations and monocytic morphology occurred more commonly in AML30 than in RAEBT. RAEBT patients were treated less often with induction therapy than AML30, whereas allogeneic stem cell transplant frequency was similar. The median and 4‐year OS of RAEBT patients were longer than those of AML30 patients (20.5 vs 12.0 months and 28.6% vs 20.4%, respectively, P = 0.003); this difference in OS was manifested in patients in the intermediate UKMRC karyotype risk group, whereas OS of RAEBT patients and AML30 patients in the adverse karyotype risk group were not significantly different. Multivariable analysis showed that RAEBT (P < 0.0001), hemoglobin (P = 0.005), UKMRC karyotype risk group (P = 0.002), normal BM karyotype (P = 0.004), treatment with induction therapy (P < 0.0001), and stem cell transplant (P < 0.0001) were associated with longer OS. Our findings favor considering de novo RAEBT as a favorable prognostic subgroup of AML. Am. J. Hematol. 89:E193–E199, 2014. © 2014 Wiley Periodicals, Inc.     

Receptor for hyaluronan acid-mediated motility (RHAMM) is a new immunogenic leukemia-associated antigen in acute and chronic myeloid leukemia

OBJECTIVE: Identification of leukemia-associated antigens (LAA) eliciting an immune response in patients is a prerequisite for specific immunotherapy of leukemias. To identify new LAA, we used the method of serologic screening of cDNA expression libraries (SEREX). MATERIALS AND METHODS: A SEREX library of the cell line K562 was subjected to allogeneic screening with sera from patients with acute myeloid leukemia (AML) or chronic myeloid leukemia (CML) vs sera from healthy volunteers. RESULTS: The receptor for hyaluronan acid-mediated motility (RHAMM) involved in cell growth and metastasis was identified as a new LAA. Serologic responses to RHAMM were observed in patients with AML (42%), CML (31%), melanoma (83%), renal cell carcinoma (40%), breast cancer (67%), and ovarian carcinoma (50%), but not in HV or patients with autoimmune diseases. RHAMM mRNA was detectable in peripheral blood mononuclear cells (PBMN) of 60% of newly diagnosed AML patients. Western blotting stained positive for RHAMM protein in 70% of AML patients. mRNA expression of RHAMM also was found in patients with CML (40%), renal cell carcinoma (73%), breast carcinoma (60%), and ovarian carcinoma (50%). In melanoma, RHAMM mRNA expression was detected in metastases (80%) but not in primary tumors. RHAMM is differentially expressed: significant mRNA expression was not found in normal tissues, except from testis, placenta, and thymus, or in PBMN- and CD34-separated cell samples of healthy volunteers. CONCLUSIONS: RHAMM is an immunogenic antigen in leukemias and solid tumors and might be a potential target structure for cellular immunotherapies and antibody therapies.     

The prognostic significance of leukemic cells clearance kinetics evaluation during the initial course of induction therapy with HAD (homoharringtonine, cytosine arabinoside, daunorubicin) in patients with de novo acute myeloid leukemia

The impact of the percentage of residual leukemic cells (RLCs) at the end of first course of induction chemotherapy (T1) or during aplasia (T2) on complete remission (CR) rate, disease-free survival (DFS), and overall survival (OS) were retrospectively analyzed in 72 cases of de novo acute myeloid leukemia (AML) treated with HAD (homoharringtonine, cytosine arabinoside, and daunorubicin) regimen. The patients were separated into two subgroups by a cutoff of 10% bone marrow leukemic cells at T1 or T2 time point. The CR rate, DFS, and OS were significantly different between the two groups. We further confirmed that the percentage of RLCs at T1 or T2 is an independent prognostic factor of AML.     

Comparative quantitative expression of bcl-2 by normal and leukaemic myeloid cells

Summary. Expression of the bcl-2 oncoprotein by AML blasts has previously been demonstrated to be heterogenous with high levels of bcl-2 expression being associated with a low complete remission rate and poor survival. We have quantified bcl-2 expression in AML blasts in relation to expression of the CD34 antigen and in comparison to CD34-positive cells from normal bone marrow. When expressed as molecules of equivalent soluble fluorochrome (MESF) per cell, AML blast cell bcl-2 expression varied from 11.1 to 99.9 × lO³ (median 39.4 × 10³, n=56) with 28.5% of patients expressing high MESF values (>50 × 10³) and 16% of patients expressing low MESF values (<20 × 10³), the remainder expressing intermediate values. There was no significant difference between intensity of bcl-2 expression and FAB classification in the de novo AML cases, and there was no significant differences between de novo and secondary AML cases. Blasts from CD34⁺ AML patients expressed significantly higher levels of bcl-2 (mean MESF 43.6 × 10³, n =36) than CD34^? AML patients (mean MESF 31.7 × 10³, n=19). In five cases of CD34⁺ AML, bcl-2 expression was determined on purified CD34⁺ and CD34^? blast cell populations. In all cases CD34⁺ blasts were found to express significantly higher bcl-2 MESF values compared to the CD34^? fraction. Purified CD34⁺ cells from normal bone marrow consistently expressed high levels of bcl-2 (MESF >75 × 10³ n = 4), which was comparable to that found on CD34⁺ AML cells. Our results suggest that the poor prognosis previously associated with AML blasts expressing the CD34 antigen may in part be related to high expression of bcl-2. Also the ability to measure bcl-2 in AML blasts quantitatively by flow cytometry and to categorize patients into discrete groups may be of value as a prognostic indicator in AML.     

Malignant progenitors from patients with CD87+ acute myelogenous leukemia are sensitive to a diphtheria toxin-urokinase fusion protein

In previous studies, we demonstrated that the diphtheria toxin-urokinase fusion protein DTAT was selectively toxic to acute myeloid leukemia (AML) cell lines overexpressing the CD87 urokinase receptor. In the present study, we analyzed the sensitivity of patient leukemic progenitors to DTAT and correlated the sensitivity with CD87 expression.We isolated leukemic blasts by density gradient centrifugation and performed immunophenotyping by flow cytometry and blast sensitivity measurements by inhibition of cell proliferation and colony formation in semisolid media.We found CD87 overexpression in 18 (25%) of 71 patient leukemic blast samples, including 18 (28%) of 64 myeloid malignancies and 0 (0%) of 7 lymphoid malignancies. DTAT was toxic to patient leukemic blasts by both proliferation inhibition (IC50 85% inhibition by 10 nM DTAT in 11/41 evaluable samples). Only AML and chronic myeloid leukemia (CML) blast crisis blasts (18/61 [30%]) were sensitive to DTAT by the proliferation inhibition assay. Lymphoid leukemia and chronic phase CML/chronic myelomonocytic leukemia (CMML) progenitors were insensitive to DTAT by the proliferation inhibition assay (n = 7 and n = 3, respectively). Similarly, normal marrow progenitors were insensitive to DTAT by both proliferation inhibition (n = 2) and colony inhibition (n = 5) assays. The DTAT toxicity measured by both proliferation inhibition assay and colony inhibition assay correlated with CD87 density (p < 0.0001 and p = 0.001, respectively). DTAT toxicity results were similar for leukemic blasts measured by either of the two assays (p = 0.0002).This study provides the first evidence that a urokinase receptor targeted diphtheria fusion protein is toxic to patient AML blasts. The work also suggests that blast proliferation assays yield similar responses to leukemia colony-forming cell colony assays.     

Azacitidine in untreated acute myeloid leukemia: A report on 149 patients

Limited data are available on azacitidine (AZA) treatment and its prognostic factors in acute myeloid leukemia (AML). One hundred and forty‐nine previously untreated AML patients considered ineligible for intensive chemotherapy received AZA in a compassionate patient‐named program. AML diagnosis was de novo, post‐myelodysplastic syndromes (MDS), post‐MPN, and therapy‐related AML in 51, 55, 13, and 30 patients, respectively. Median age was 74 years, median white blood cell count (WBC) was 3.2 × 10⁹/L and 58% of the patients had ≥30% marrow blasts. Cytogenetics was adverse in 60 patients. Patients received AZA for a median of five cycles (range 1–31). Response rate (including complete remission/CR with incomplete recovery/partial remission) was 27.5% after a median of three cycles (initial response), and 33% at any time (best response). Only adverse cytogenetics predicted poorer response. Median overall survival (OS) was 9.4 months. Two‐year OS was 51% in responders and 10% in non‐responders (P<0.0001). Adverse cytogenetics, WBC >15 × 10⁹/L and ECOG‐PS ≥2 predicted poorer OS, while age and marrow blast percentage had no impact. Using MDS IWG 2006 response criteria, among patients with stable disease, those with hematological improvement had no significant survival benefit in a 7 months landmark analysis. Outcomes observed in this high‐risk AML population treated with AZA deserve comparison with those of patients treated intensively in prospective studies. Am. J. Hematol. 89:410–416, 2014. © 2013 Wiley Periodicals, Inc.     

RHAMM-R3 peptide vaccination in patients with acute myeloid leukemia, myelodysplastic syndrome, and multiple myeloma elicits immunologic and clinical responses

The receptor for hyaluronic acid-mediated motility (RHAMM) is an antigen eliciting both humoral and cellular immune responses in patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), and multiple myeloma (MM). We initiated a phase 1 clinical trial vaccinating 10 patients with R3 (ILSLELMKL), a highly immunogenic CD8(+) T-cell epitope peptide derived from RHAMM. In 7 of 10 patients, we detected an increase of CD8(+)/HLA-A2/RHAMM R3 tetramer(+)/CD45RA(+)/CCR7(-)/CD27(-)/CD28(-) effector T cells in accordance with an increase of R3-specific CD8(+) T cells in enzyme linked immunospot (ELISpot) assays. In chromium release assays, a specific lysis of RHAMM-positive leukemic blasts was shown. Three of 6 patients with myeloid disorders (1/3 AML, 2/3 MDS) achieved clinical responses: one patient with AML and one with MDS showed a significant reduction of blasts in the bone marrow after the last vaccination. One patient with MDS no longer needed erythrocyte transfusions after 4 vaccinations. Two of 4 patients with MM showed a reduction of free light chain serum levels. Taken together, RHAMM-R3 peptide vaccination induced both immunologic and clinical responses, and therefore RHAMM constitutes a promising target for further immunotherapeutic approaches. This study is registered at http://ISRCTN.org as ISRCTN32763606 and is registered with EudraCT as 2005-001706-37.     

Early blast clearance by remission induction therapy is a major independent prognostic factor for both achievement of complete remission and long-term outcome in acute myeloid leukemia: data from the German AML Cooperative Group (AMLCG) 1992 Trial

Risk assessment in acute myeloid leukemia (AML) using pretreatment characteristics may be improved by incorporating parameters of early response to therapy. In the 1992 trial of the German AML Cooperative Group (AMLCG), the amount of residual leukemic blasts in bone marrow was assessed one week after the first induction course (day 16 blasts). A total of 449 patients 16 to 76 years of age (median, 53 years) with de novo AML entered the trial and were evaluable. Treatment included TAD/HAM (thioguanine, cytosine arabinoside, and daunorubicin/high-dose cytosine arabinoside and mitoxantrone) double induction, TAD consolidation, and randomly either maintenance therapy or S-HAM consolidation. Cytogenetics were favorable, intermediate, unfavorable and not available in 10.0%, 48.3%, 13.1%, and 28.5%, respectively. Day 16 blasts ranged from 0% to 100% (median, 5%, mean +/- SD, 18.6 +/- 28.5%). Complete remission (CR) rate was 72.6%, 17.6% had persistent leukemia (PL), and 9.8% succumbed to hypoplastic death. Median overall survival (OS), event-free survival (EFS), and relapse-free survival (RFS) were 18, 9, and 15 months with 28.4%, 21.6%, and 30.1% at 5 years, respectively. As a continuous variable, day 16 blasts were related to CR rate (P < 0.0001), PL rate (P < 0.0001), OS (P < 0.0001), EFS (P < 0.0001), and RFS (P = 0.0049). Multivariate analyses identified the following parameters to be associated with the respective end points. CR rate: day 16 blasts (P <.0001), age (P =.0036), and LDH (P =.0072); OS: unfavorable cytogenetics (P <.0001), day 16 blasts (P <.0001), age (P <.0001), and LDH (P =.0040); EFS: unfavorable cytogenetics (P <.0001), LDH (P <.0001), day 16 blasts (P <.0001), and age (P =.0061); RFS: unfavorable cytogenetics (P <.0001), LDH (P <.0001), and day 16 blasts (P =.0359). The prognostic significance of day 16 blasts is independent of pretherapeutic parameters and predicts outcome even in patients achieving a CR.     

Prognostic factors for response and overall survival in 282 patients with higher-risk myelodysplastic syndromes treated with azacitidine

Prognostic factors for response and survival in higher-risk myelodysplastic syndrome patients treated with azacitidine (AZA) remain largely unknown. Two hundred eighty-two consecutive high or intermediate-2 risk myelodysplastic syndrome patients received AZA in a compassionate, patient-named program. Diagnosis was RA/RARS/RCMD in 4%, RAEB-1 in 20%, RAEB-2 in 54%, and RAEB-t (AML with 21%-30% marrow blasts) in 22%. Cytogenetic risk was good in 31%, intermediate in 17%, and poor in 47%. Patients received AZA for a median of 6 cycles (1-52). Previous low-dose cytosine arabinoside treatment (P = .009), bone marrow blasts > 15% (P = .004), and abnormal karyotype (P = .03) independently predicted lower response rates. Complex karyotype predicted shorter responses (P = .0003). Performance status ≥ 2, intermediate- and poor-risk cytogenetics, presence of circulating blasts, and red blood cell transfusion dependency ≥ 4 units/8 weeks (all P < 10(-4)) independently predicted poorer overall survival (OS). A prognostic score based on those factors discriminated 3 risk groups with median OS not reached, 15.0 and 6.1 months, respectively (P < 10(-4)). This prognostic score was validated in an independent set of patients receiving AZA in the AZA-001 trial (P = .003). Achievement of hematological improvement in patients who did not obtain complete or partial remission was associated with improved OS (P < 10(-4)). In conclusion, routine tests can identify subgroups of patients with distinct prognosis with AZA treatment.     

Low L-selectin (CD62L) expression in acute myeloid leukemia correlates with a bad cytogenetic risk

OBJECTIVES: Interactions between hemopoietic cells and the stromal microenvironment or immunoreactive cells are mediated by specific cell surface receptors. The expression of those molecules may alter the adhesive qualities (mobility and homing) as well as immune response behavior of leukemic blasts. L-Selectin (CD62L) is suggested to play a role in the redistribution and homing of hemopoietic progenitor cells to the bone marrow (BM). Down-regulation of L-selectin is responsible for mobilization of blasts from the BM into the circulation and ligation of L-selectin stimulates proliferation of progenitor cells. This could have an influence on the process of leukemia. METHOD: We have studied the expression of L-selectin on mononuclear BM cells of 36 acute myeloid leukemia (AML) patients at first diagnosis by FACS analysis using a directly fluorescein isothiocyanate conjugated antibody (clone DRE G56). RESULTS: On average the patients presented with 88% blasts in the BM. The expression tended to be higher in primary (p) AML compared with secondary (s) AML. L-Selectin was very heterogenously expressed in all FAB groups. Highest expression was found in cases with AML-M4 with four of nine cases presenting with an inv(16) karyotype. Separating our patient cohort in cytogenetic risk groups we could detect a significantly higher expression of L-selectin in cases with a 'good risk' karyotype and a very low expression in cases with a 'bad risk' karyotype (P = 0.037). Comparing patients who achieved remission after double induction therapy (responders) with patients who showed persisting disease (non-responders) we found a higher percentage of L-selectin+ cases or cells in the responder group than in the non-responder group, although the differences were not significant because of only five cases in the 'non-responder' group. Evaluating cut-off points greatest differences in relapse-free survival probabilities were found in patients who presented with > or = 30% L-selectin+ BM cells compared with cases with < 30%: 86% of cases with > or = 30% L-selectin+ cells were still in remission after a mean follow up time of only 8 months compared with only 46% in the group with < 30% L-selectin+ cells. CONCLUSIONS: We can conclude that (i) expression of L-selectin on AML blasts is variable. This reveals the great diversitiy of immunophenotypes in AML and might contribute to identify individual blast phenotypes in order to detect minimal residual disease in remission. (ii) Low L-selectin expression correlates with a bad cytogenetic risk, with a lower probability to achieve remission and with a shorter relapse-free survival time. This might reflect a decreased homing of the blasts to the BM as well as an impaired cytotoxic T-cell reaction against leukemic cells. The expression of L-selectin on leukemic blasts might be influenced by different cytokine therapies (e.g. with interferon alpha) and this might result in an altered hematologic reconstitution after cytotoxic therapies as well as in an altered immunologic recognition of blasts.     

急性髓系白血病患者预后分组方式的探讨

目的 评价原发、初治急性髓系白血病(AML)患者诱导治疗后不同时间骨髓幼稚细胞比例对预后的影响.将细胞遗传学与诱导治疗后不同时间骨髓幼稚细胞比例相结合,提出新的AML患者预后分组方法.方法 回顾性分析1999年1月1日至2008年2月1日于我院住院的原发、初治AML患者(非M3型)105例,所有患者在诱导化疗结束时(T1)和(或)骨髓抑制期(T2)进行骨髓穿刺检查.有细胞遗传学资料的患者97例.结果 (1)T1或T2时间点105例行骨髓穿刺检查的患者,骨髓幼稚细胞<0.05者和≥0.05者相比,T1时间点完全缓解(CR)率分别为86.0%、47.4%,3年无复发生存(RFS)率分别为46.2%、21.6%,3年总生存率分别为49.7%、25.6%.T2时间点二者CR率分别为86.3%、41.4%,3年RFS率分别为52.4%、18.9%,3年总生存率分别为61.1%、35.2%,差异均有统计学意义.且T1和,12时间点骨髓幼稚细胞比例具有相关性.(2)将染色体核型预后中等组患者根据T1或T2时间点骨髓幼稚细胞比例分为二组:骨髓幼稚细胞<0.05者和≥0.05者.前者预后与良好组相近,后者预后与不良组相近.(3)多因素分析表明T1或12时间点骨髓幼稚细胞比例是AML患者的独立预后因素.T1时间点骨髓幼稚细胞比例可能较T2时间点骨髓幼稚细胞比例意义更大.结论 以0.05为界,T1或T2时间点骨髓幼稚细胞比例是原发、初治AML患者(非M3型)CR率、RFS、总生存的独立预后因素.将染色体核型与T1和(或)T2时间点骨髓幼稚细胞比例相结合分组,可进一步区分中等组患者,有助于评估预后和选择治疗方案.     

BAALC and ERG expression in acute myeloid leukemia with normal karyotype: impact on prognosis

Cytogenetic aberrations are important prognostic factors in acute myeloid leukemia (AML). About 45% of de novo AML lack cytogenetic abnormalities, so identification of predictive molecular markers might improve therapy. We studied the prognostic impact of brain and acute leukemia, cytoplasmic (BAALC) and ETS-related gene (ERG) expression in AML with normal karyotype. Pretreatment bone marrow samples from 30 cytogenetically normal AML patients were analysed for BAALC and ERG expression using real time RT-PCR. The patients were dichotomized at BAALC and ERG mean expression into low and high expression. BAALC showed high expression in 70% of patients and its expression did not correlate with the clinical parameters of patients. ERG was high in 33.3% of patients and its expression was associated with lower ages and higher white cell counts. With follow-up for 2 years, patients with high BAALC and high ERG had low rates of clinical remission (P < 0.005) and inferior overall survival (OS) (P < 0.001 and <0.002 for BAALC and ERG respectively). No significant association was observed between the increase in BAALC and ERG expression (P = 0.398). Multivariable analysis confirmed high BAALC expression as an independent risk factor for OS. Overexpression of BAALC and ERG either separate or concomitant predict adverse clinical outcome and may define important risk factor in cytogenetically normal AML.     

Deoxycytidine kinase expression and activity in patients with resistant versus sensitive acute myeloid leukemia

Resistance to cytarabine (AraC) is a major problem in treatment of patients with acute myeloid leukemia (AML). In contrast to in vitro AraC resistance, deoxycytidine kinase (dCK) mutations are rarely found in patients with refractory or relapsed AML. Previously we have demonstrated alternatively spliced dCK mRNA predominantly expressed in leukemic blasts from patients with resistant AML. In this study we investigated wild-type (wt) dCK expression and activity to elucidate the possible role of decreased dCK expression or activity in unresponsiveness to AraC in patients with AML. No alterations in dCK mRNA and protein expression or in dCK activity were detected between patients with clinically resistant vs. sensitive AML. In addition, wt dCK expression and activity were not reduced in leukemic blasts expressing alternatively spliced dCK forms as compared to blasts with only wt dCK. Also, no major differences in wt dCK expression and activity were observed between samples obtained from patients with AML and bone marrow or peripheral blood samples from healthy donors. These data implicate that in our patient group of refractory or relapsed AML cases, alterations in dCK expression and/or activity cannot explain unresponsiveness to chemotherapy including AraC.     

5‐Azacytidine treatment for relapsed or refractory acute myeloid leukemia after intensive chemotherapy

Despite progress in the understanding of leukemia pathophysiology, the treatment of acute myeloid leukemia (AML) remains challenging. In patients with refractory or relapsed (R/R) AML, the prognosis is still poor and this group is targeted for new drug development. We reviewed the outcome of 47 patients, with R/R AML after at least one course of intensive chemotherapy, treated with 5‐azacytidine in three different French institutions. The overall response rate was 38% including complete remission in 21%, partial remission in 11%, and hematological improvement in 6% of cases. Median time to relapse was 6 (range, 1–39) months. Median overall survival was 9 months (not reached by responders vs. 4.5 months for nonresponders patients, P = 0.0001). Univariate analysis identified the absence of peripheral blood blasts and <20% bone marrow blasts as prognostic factors for both overall response and survival, but not age, ECOG/PS, type of AML, cytogenetic, status of the disease, number of previous lines of therapy, previous hematological stem cell transplantation, or white blood cells count. Bone marrow blasts percentage <20% was the only independent prognostic factor identified by multivariate analysis for overall response (P = 0.0013) and survival (P = 0.0324). Six patients in remission could proceed to an allogenic hematological stem cell transplantation. The drug‐related grade 3/4 adverse events were hematopoietic toxicities (38%) and infection (32%). In conclusion, this study suggests that a salvage therapy with 5‐azacytidine is an interesting option for patients with R/R AML after intensive chemotherapy. Prospective randomized studies are needed to demonstrate a superiority of this approach over others strategies. Am. J. Hematol. 88:601–605, 2013. © 2013 Wiley Periodicals, Inc.     

Early peripheral blood blast clearance during induction chemotherapy for acute myeloid leukemia predicts superior relapse-free survival

In childhood acute lymphoblastic leukemia (ALL), a rapid decline of circulating leukemic blasts in response to induction chemotherapy or prednisone is one of the most important prognostic factors, not only for achieving remission but also for relapse-free survival (RFS). However, in acute myeloid leukemia (AML) parameters of chemosensitivity have been restricted mainly to the rapidity of achievement of complete remission (CR) or the assessment of residual leukemic bone marrow blasts during aplasia. We hypothesized that the time to circulating peripheral blood blast clearance, as a potential surrogate for in vivo chemosensitivity, would have prognostic relevance in AML also. In a retrospective analysis of a cohort of 86 adult patients with AML receiving uniform induction and consolidation chemotherapy, we demonstrate that the time to clearance of circulating blasts during induction chemotherapy is an independent prognostic marker of RFS, superseding other known or established risk factors, including karyotype and number of inductions to achieve CR.     

The generation of immunocompetent dendritic cells from CD34+ acute myeloid or lymphoid leukemia cells

The ability of CD34+ leukemic cells to differentiate to dendritic cells (DCs) was investigated in 18 acute myeloid leukemia (AML) and 4 lymphoid leukemia (ALL) patients. The generation of DCs was determined by the expression of DC-associated CD1a or CD83 (more than 30%) with costimulatory molecules, by CD80 antigens (>20%), and by the exhibition of allostimulatory activity. In the AML patients, allostimulatory mature DCs were generated from 3 of 9 M0 or M1, 2 of 5 M2,2 of 4 M4 or M5, and 3 of 4 ALL (L2) cases. In total, DCs were more efficiently induced from cases expressing over 75% of CD34+ among whole bone marrow mononuclear cells (8 of 12), compared with those under 75% (2 of 10; P < .05). B-cell (CD19), natural killer (NK)-cell (CD56), or T-cell (CD7) lineage markers, which were aberrantly expressed on the blasts, were rarely found on leukemic DCs at the end of the culture period, and myeloid (CD13, CD33), not lymphoid (CD10), markers were shown on ALL-derived DCs. In Philadelphia chromosome-positive ALL or AML patients with t (8;21), DCs were confirmed to be of leukemic origin by fluorescence in situ hybridization analysis.     

Acute myelogenous leukemia (FAB AML-M1) in the setting of HIV infection and G-CSF therapy: a case report and review of the literature

Although hematologic dysplasia is common in HIV disease, evolution to AML is unusual. We report a case of AML in a patient with stage-C3 AIDS who had been previously treated with granulocyte colony-stimulating factor (G-CSF). This 41-year-old black man presented with pancytopenia (Hg 8.6 g/dl, Hct 24.3%, platelets 16,000/mm³, WBC 0.6× 10³/mm³) and hemoptysis. His peripheral smear manifested 19% blasts. His bone marrow biopsy was hypocellular (20%) with greater than 90% blasts, which were positive for myeloperoxidase and Sudan black B. The blasts were negative for nonspecific esterase. Immunophenotypic analysis by flow cytometry showed the majority of cells to be of myeloid lineage, expressing CD13, and CD45 at low intensity. In addition, there was aberrant expression of CD2 and no expression of CD14 or CD4. The diagnosis of AML-FAB-M1 was made. The patient refused chemotherapy. Of the rare cases of AML in HIV patients previously reported in the literature, the majority were of the monocytic or myelomonocytic subtype. This case is of special interest because of prior G-CSF therapy. In this setting, the relationship between HIV, G-CSF, and subsequent AML is controversial. Received: October 28, 1997 Accepted: March 31, 1998     

Impact of pre-transplant marrow blasts on survival of allogeneic stem cell transplantation in adult acute myeloid leukemia

The aim of this study was to evaluate the impact of marrow blasts at transplant in adult acute myeloid leukemia (AML) patients. We analyzed 478 patients who underwent allogeneic stem cell transplantation (SCT). All patients were divided into five subgroups according to the percentage of blasts: <2 % (n = 361), ≥2 to<3 % (n = 64), ≥3 to <5 % (n = 28), ≥5 to <12 % (n = 11), and ≥12 % (n = 4). After a median follow-up of 59.5 months (range 3.3–125.9 months) for survivors, patients with higher marrow blasts at transplant showed lower overall survival (OS) and disease-free survival (DFS). In multivariate analyses, OS and DFS did not show significant differences with blast counts up to 12 %, compared with blast counts of <2 %; by contrast, the presence of >12 % marrow blasts was associated with significantly poorer OS and DFS. In the separate multivariate analyses by cytogenetic risk group, the impact of >12 % marrow blast on survival outcomes was observed in all risk groups. Thus, pre-transplant bone marrow status is an important prognostic factor for AML patients. In addition, the higher relapse rate in patients with >12 % marrow blasts may provide insights into the tolerable blast cell burden that can be overcome by the graft-versus leukemia effect.