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We conducted a multicenter, prospective observational study of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and chronic myelomonocytic leukemia (CMML) in Japan. From August 2011 to January 2016, we enrolled 6568 patients. Herein, we report the results for MDS (n = 2747) and CMML (n = 182). The percentage of patients aged 65 years or older was 79.5% for MDS and 79.7% for CMML. The estimated overall survival (OS) rate and cumulative incidence of AML evolution at 5 years were 32.3% (95% confidence interval: 30.2-34.5%) and 25.7% (23.9-27.6%) for MDS, and 15.0% (8.9-22.7%) and 39.4% (31.1-47.6%) for CMML. Both diseases were more common in men. The most common treatment for MDS was azacitidine, which was used in 45.4% of higher-risk and 12.7% of lower-risk MDS patients. The 5-year OS rate after treatment with azacitidine was 12.1% (9.5-15.1%) for of higher-risk MDS patients and 33.9% (25.6-42.4%) for lower-risk patients. The second most common treatment was erythropoiesis-stimulating agents, given to just 20% of lower-risk patients. This is the first paper presenting large-scale, Japanese data on survival and clinical characteristics in patients with MDS and CMML., (© 2023. Japanese Society of Hematology.)

This report covers acute myeloid leukemia (AML) results from a multicenter, prospective observational study of AML, myelodysplastic syndromes, and chronic myelomonocytic leukemia in Japan. From August 2011 to January 2016, 3728 AML patients were registered. Among them, 42% were younger than 65, and the male-to-female ratio was 1.57:1. With a median follow-up time of 1807 days (95% confidence interval [CI]: 1732-1844 days), the estimated 5-year overall survival (OS) rate in AML patients (n = 3707) was 31.1% (95% CI: 29.5-32.8%). Trial-enrolled patients had a 1.7-fold higher OS rate than non-enrolled patients (5-year OS, 58.9% [95% CI: 54.5-63.1%] vs 35.5% [33.3-37.8%], p < 0.0001). Women had a higher OS rate than men (5-year OS, 34% [95% CI; 31.4-36.7%] vs 27.7% [25.7-29.7%], p < 0.0001). The OS rate was lower in patients aged 40 and older than those under 40, and even lower in those over 65 (5-year OS for ages < 40, 40-64, 65-74, ≥ 75: 74.5% [95% CI; 69.3-79.0%] vs 47.5% [44.4-50.6%] vs 19.3% [16.8-22.0%] vs 7.3% [5.5-9.4%], respectively). This is the first paper to present large-scale data on survival and clinical characteristics in Japanese AML patients., (© 2023. Japanese Society of Hematology.)

Given the poor prognosis of patients with relapsed/refractory acute myeloid leukemia (AML), better therapy is needed. Fludarabine enhances the efficacy of Ara-C (cytarabine) by increasing intracellular Ara-C-triphosphate. The FLAG (fludarabine, high-dose Ara-C, supported with granulocyte colony-stimulating factor) regimen has been tested for use in AML patients by other investigators. In the phase II study reported here, we evaluated the efficacy and toxicity of FLAGM therapy (FLAG with mitoxantrone), further intensified by adding mitoxantrone, based on the results of a phase I study by our group. The major endpoints were complete remission (CR) rate and early death. From June 2004 to February 2008, 41 patients (median age 52 years; range 18-64 years) were enrolled. Thirty (73% 95% CI 58-84%) patients achieved CR, which met the primary endpoint; there was a single case of early death from pneumonia. Two-year overall survival was 39.4% (95% CI 25.2-55.6%). Of those who achieved CR, 27 underwent allogeneic stem cell transplantation (SCT), and 12 SCT recipients showed long-term survival. Grade 3/4 non-hematological adverse events included infection (59%), nausea/vomiting (15%), diarrhea (7%), and elevated liver enzymes (7%). In conclusion, FLAGM is an effective and safe salvage therapy for patients with relapsed/refractory AML, and facilitated SCT for a large proportion of patients.

We analyzed the clinical significance and genetic features of ASXL2 and ZBTB7A mutations, and the alternatively spliced isoform of the RUNX1-RUNX1T1 transcript, which is also called AML1-ETO9a (AE9a), in Japanese CBF-AML patients enrolled in the JALSG AML201 study. ASXL2 and ZBTB7A genes were sequenced using bone marrow samples of 41 AML patients with t(8;21) and 14 with inv(16). The relative expression levels of AE9a were quantified using the real-time PCR assay in 23 AML patients with t(8;21). We identified ASXL2 (34.1%) and ZBTB7A (9.8%) mutations in only AML patients with t(8;21). ASXL2-mutated patients had a significantly higher WBC count at diagnosis (P = 0.04) and a lower frequency of sex chromosome loss than wild-type patients (33 vs. 76%, respectively, P = 0.01). KIT mutations were the most frequently accompanied with both ASXL2 (36%) and ZBTB7A (75%) mutations. Neither ASXL2 nor ZBTB7A mutations had an impact on overall or event-free survival. Patients harboring cohesin complex gene mutations expressed significantly higher levels of AE9a than unmutated patients (P = 0.03). In conclusion, ASXL2 and ZBTB7A mutations were frequently identified in Japanese AML patients with t(8;21), but not in those with inv(16). Further analysis is required to clarify the detailed biological mechanism of AE9a regulation of the cohesin complex.

Many genetic alterations that are associated with the prognosis of acute myeloid leukemia (AML) have been identified, and several risk stratification systems based on the genetic status have been recommended. The European LeukemiaNet (ELN) first proposed the risk stratification system for AML in 2010 (ELN-2010), and recently published the revised system (ELN-2017). We validated the long-term prognosis and clinical characteristics of each ELN-2017 risk category in Japanese adult AML patients who were treated in the Japan Adult Leukemia Study Group (JALSG) AML-201 study. We demonstrated that the 3-risk category system of the ELN-2017 successfully discriminated the overall survival and complete remission rates in our cohort in comparison with the 4-risk category of the ELN-2010. However, there were still genetic categories in which stratification of patients into favorable or intermediate risk categories was controversial; the low allelic ratio of FLT3-ITD was not necessarily associated with a better prognosis in patients with FLT3-ITD, and cytogenetic abnormalities may affect the prognosis in patients with favorable genetic lesions such as NPM1 and CEBPA mutations. As many molecular targeting agents, such as FLT3 inhibitors, have been developed, we must continue to modify the genetic risk stratification system to match the progression of therapeutic strategies., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Clinical outcomes and the genetic background of acute myeloid leukemia (AML) in adolescent and young adults (AYAs) are known to differ in younger children and older adults. To clarify the impact of genetic mutations on clinical outcomes of AYAs with AML, we analyzed data from the JPLSG AML-05 and JALSG AML201 studies. AYAs aged 15-39 years (n = 103) were included. FLT3-ITD, KIT, CEBPA, NRAS, KRAS, WT1, MLL-PTD, and NPM1 mutations were analyzed. Overall survival (OS) of the AYAs was 61% and event-free survival was 38% at 3 years. FLT3-ITD (HR 2.10; 95% CI 1.07-4.12; p = 0.031) and NPM1 (HR 0.24; 95% CI 0.06-1.00; p = 0.050) mutations were associated with risk of overall mortality in multivariate analysis. OS was significantly different according to FLT3-ITD and NPM1 mutation status (p = 0.03). Survival was 100% with NPM1 mutations in the absence of FLT3-ITD and 35% (95% CI 14-57%) with FLT3-ITD in the absence of NPM1 mutations. The OS of AYAs, children (n = 413) and older adults (n = 124) of the AML-05 and AML201 participants were significantly different (p < 0.0001). This is the first report to combine clinical and genetic data of AYA AML from the major Japanese pediatric and adult study groups.

Recent studies have described various impacts of obesity and being overweight on acute myeloid leukemia (AML) outcomes in adult patients, but little is known about the impact of being underweight. We compared the outcomes of underweight patients to those of normal weight and overweight patients. Adult patients with AML who registered in the JALSG AML201 study (n = 1057) were classified into three groups: underweight (body mass index [BMI] < 18.5, n = 92), normal weight (BMI 18.5-25, n = 746), and overweight (BMI ≥ 25, n = 219). With the exception of age and male/female ratio, patient characteristics were comparable among the three groups. Rates of complete remission following induction chemotherapy were similar among the three groups (p = 0.68). We observed a significant difference in overall survival (OS), disease-free survival (DFS), and non-relapse mortality (NRM) between underweight and normal weight patients (3-year OS 34.8 vs. 47.7%, p = 0.01; DFS 28.6 vs. 39.8%, p = 0.02; 1-year NRM 6.2 vs. 2.6%, p = 0.05), but not between underweight and overweight patients. In multivariate analysis, underweight was an independent adverse prognostic factor for OS (p < 0.01), DFS (p = 0.01), and NRM (p = 0.04). During the first induction chemotherapy, the incidences of documented infection (DI) and severe adverse events (AEs) were higher in underweight patients than those in normal weight patients (DI 16 vs. 8.1%, p = 0.04; AE 36 vs. 24%, p = 0.05). In conclusion, underweight was an independent adverse prognostic factor for survival in adult AML patients.

To clarify the cooperative roles of recurrently identified mutations and to establish a more precise risk classification system in acute myeloid leukemia (AML), we comprehensively analyzed mutations in 51 genes, as well as cytogenetics and 11 chimeric transcripts, in 197 adult patients with de novo AML who were registered in the Japan Adult Leukemia Study Group AML201 study. We identified a total of 505 mutations in 44 genes, while only five genes, FLT3, NPM1, CEBPA, DNMT3A and KIT, were mutated in more than 10% of the patients. Although several cooperative and exclusive mutation patterns were observed, the accumulated mutation number was higher in cytogenetically normal AML and lower in AML with RUNX1-RUNX1T1 and CBFB-MYH11, indicating a strong potential of these translocations for the initiation of AML. Furthermore, we evaluated the prognostic impacts of each sole mutation and the combinations of mutations and/or cytogenetics, and demonstrated that AML patients could be clearly stratified into five risk groups for overall survival by including the mutation status of DNMT3A, MLL-PTD and TP53 genes in the risk classification system of the European LeukemiaNet. These results indicate that the prognosis of AML could be stratified by the major mutation status in combination with cytogenetics.

In order to investigate better molecular-target therapy for acute myeloid leukemia (AML), we conducted a phase I trial of a combination of gemtuzumab ozogamicin (GO) with conventional chemotherapy. Between January 2007 and December 2009, a total of 19 adult Japanese patients with relapsed or refractory CD33-positive AML (excluding acute promyelocytic leukemia) were enrolled. All registered patients received a standard dose of cytarabine (Ara-C) (100 mg/m(2) × 7 days), combined with either idarubicin (IDR) (10-12 mg/m(2) × 3 days) or daunorubicin (DNR) (50 mg/m(2) × 3-5 days), and then GO (3-5 mg/m(2) ), which was administered 1 day after the last infusion of IDR (IAG regimen) or DNR (DAG regimen). While doses of both GO and IDR and the administration period of only DNR were increased, the dose-limiting toxicity (DLT) was assessed. Among 19 patients (nine in the IAG regimen, 10 in the DAG regimen), the median age was 59 years (range 33-64), and the relapsed/refractory ratio was 13/6. In the therapy using 3 mg/m(2) GO in the IAG or DAG regimen, grade 3/4 leukopenia and neutropenia were observed in all patients, but none had grade 3/4 non-hematological toxicities, except febrile neutropenia. Three patients in the IAG regimen who were administered 5 mg/m(2) GO showed DLT. No patients had veno-occlusive disease or sinusoidal obstructive syndrome. In conclusion, 3 mg/m(2) GO combined with Ara-C and IDR or DNR can be safely administered, and phase II trials should be conducted to investigate the clinical efficacy of the combination therapy., (© 2011 Japanese Cancer Association.)

We evaluated the efficacy of daunorubicin  (40 mg/m(2)/day for 5 days, 200 mg/m(2)/cycle) combined with standard dose of cytarabine (100 mg/m(2)/day for 7 days) for acute myelogenous leukemia patients aged 65-74 years as induction therapy. Complete remission (81.3%) was achieved in 13 of 16 patients following the therapeutic program. The median duration of recovering absolute neutolophilic counts over 1000/µl and platelet counts over 100 000/µl were 33 days and 27 days, respectively. None of the patients had any adverse cardiac complications or died during administration of the induction therapy. Patients achieving complete remission received post-remission therapy consisting of two regimens other than induction therapy. The 3-year disease-free and overall survival rates were 36.9 and 50.0%, respectively. Extending the total period of the daunorubicin therapy might be an alternative to increasing the daily dose of daunorubicin in the induction therapy for elderly patients who were candidates for receiving intensified chemotherapy.

We conducted a multi-institutional randomized study to determine whether high-dose daunorubicin would be as effective as standard-dose idarubicin in remission-induction therapy for newly diagnosed adult patients younger than 65 years of age with acute myeloid leukemia. Of 1064 patients registered, 1057 were evaluable. They were randomly assigned to receive either daunorubicin (50 mg/m(2) daily for 5 days) or idarubicin (12 mg/m(2) daily for 3 days) in combination with 100 mg/m(2) of cytarabine by continuous infusion daily for 7 days as induction therapy. Complete remission was achieved in 407 (77.5%) of 525 patients in the daunorubicin group and 416 (78.2%) of 532 in the idarubicin group (P = .79). Patients achieving complete remission received intensive postremission therapy that consisted of either 3 courses of high-dose cytarabine or 4 courses of standard-dose therapy. Overall survival rates at 5 years were 48% for the daunorubicin group and 48% for the idarubicin group (P = .54), and relapse-free survival rates at 5 years were 41% and 41% (P = .97), respectively. Thus, high-dose daunorubicin and standard-dose idarubicin were equally effective for the treatment of adult acute myeloid leukemia, achieving a high rate of complete remission and good long-term efficacy. This study is registered at http://www.umin.ac.jp/ctrj/ as C000000157.

We conducted a prospective randomized study to assess the optimal postremission therapy for adult acute myeloid leukemia in patients younger than 65 years in the first complete remission. A total of 781 patients in complete remission were randomly assigned to receive consolidation chemotherapy of either 3 courses of high-dose cytarabine (HiDAC, 2 g/m(2) twice daily for 5 days) alone or 4 courses of conventional standard-dose multiagent chemotherapy (CT) established in the previous JALSG AML97 study. Five-year disease-free survival was 43% for the HiDAC group and 39% for the multiagent CT group (P = .724), and 5-year overall survival was 58% and 56%, respectively (P = .954). Among the favorable cytogenetic risk group (n = 218), 5-year disease-free survival was 57% for HiDAC and 39% for multiagent CT (P = .050), and 5-year overall survival was 75% and 66%, respectively (P = .174). In the HiDAC group, the nadir of leukocyte counts was lower, and the duration of leukocyte less than 1.0 × 10(9)/L longer, and the frequency of documented infections higher. The present study demonstrated that the multiagent CT regimen is as effective as our HiDAC regimen for consolidation. Our HiDAC regimen resulted in a beneficial effect on disease-free survival only in the favorable cytogenetic leukemia group. This trial was registered at www.umin.ac.jp/ctr/ as #C000000157.

It is difficult to decide an appropriate treatment strategy for elderly leukemia patients with other complications. We encountered 2 cases of refractory acute myeloid leukemia and safely treated the patients with fractionated administration of gemtuzumab ozogamicin (GO). Standard induction therapies were not effective for these patients. Moreover, they suffered from complications due to which their treatment options were restricted. Fractionated administration of GO (GO 3 mg/m(2) on days 1, 3 and 5) was accomplished safely and alleviated the patients' conditions. After treatment, these patients were followed by outpatient basis. We consider that this is an impressive treatment because fractionated administration of GO is potentially less toxic. Further, it will be helpful to maintain or improve the QOL of patients who are unable to receive intensive chemotherapy. These cases were significant because fractionated GO treatment is potentially less toxic and it will be helpful to maintain or improve the QOL of patients who can not receive intensive chemotherapy.

Objective: Gemtuzumab ozogamicin (GO) is a humanized anti-CD33 antibody, linked to calicheamicin, which has been approved in Japan recently. We conducted to evaluate the efficacy and toxicity of GO in our patients with relapsed or refractory AML retrospectively., Patients and Methods: Data were collected between March 1, 2000, and March 1, 2006, on 10 patients with relapsed or refractory AML(excluding FAB: M3). Scheduled treatment was two doses of GO monotherapy, 14-28 days apart., Results: Of the 10 assessable patients, two patients achieved CR. CR duration of one patient lasted for 52 months with post-remission treatment. Grade 4 neutropenia occurred in 9 patients, and the incidence of grade 3 or 4 thrombocytopenia was 100%, with no severe bleeding events. Two patients developed infusion-related adverse events that included grade 3 allergic reaction with shock status. Liver damage (grade 3 or 4) were observed in 40% of patients after GO treatment. No patient developed hepatic veno-occlusive disease including 2 patients who underwent HSCT., Conclusion: GO is a valuable new treatment option for relapsed or refractory AML patients, however, the benefit from single agent appears insufficient. On going clinical trials including combination with other antileukemic agents might better define the role of GO.

The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of gemtuzumab ozogamicin (GO) in patients with relapsed and/or refractory CD33-positive acute myeloid leukemia (AML). Patients received 2-h infusions of GO twice with an interval of approximately 14 days. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria Version 2.0. Samples for pharmacokinetics were taken on day 1 and day 8 of the first treatment cycle. The dose was increased stepwise and, in each cohort, patients were treated at the same dose. Forty patients, median age 58 years (range 28-68) were treated; 20 and 20 patients were enrolled to the phase I and II parts, respectively. In the phase I part, dose-limiting toxicities (DLTs) were hepatotoxicities, and the recommended dose was established as 9 mg/m2 given as two intravenous infusions separated by approximately 14 days. The pharmacokinetic study revealed that Cmax and AUC were equivalent to those of non-Japanese patients. In the phase II part, complete remission was observed in 5 patients, and one patient had complete remission without platelet recovery. Four of these 6 in remission and one in the phase I are long-term survivors (alive for at least 44 months). GO is safe and effective as a single agent among Japanese CD33-positive AML patients. Remission lasted longer in a subset of patients than in non-Japanese patients in earlier studies. Further studies of this agent are warranted to establish standard therapy.

To clarify the clinical features of adult patients with acute leukemia (AL) with 11q23 abnormalities, we performed a retrospective analysis of data from 58 adult Japanese patients: 51 with acute myeloid leukemia (AML), and 7 with acute lymphoblastic leukemia (ALL). The incidences according to fusion partners in AML were: t(9;11), 31.3%; t(11;19), 27.4%; t(6;11), 21.5%. The incidence of patients with t(11;19) was higher than those in the US and Europe, and the incidence of t(4;11) was lower than that in childhood. The results indicated the poor prognosis of AML with 11q23 abnormalities regardless of the fusion partners. AML patients with 11q23 aged <60 years in the first CR who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) showed a more favorable outcome than those treated without allo-HSCT, although the differences were not statistically significant (P = 0.322 for DFS, P = 0.138 for OS). This result suggests that treatment strategies including allo-HSCT may be considered in the first CR in cases of AML with 11q23 abnormalities. However, further studies involving a large number of cases are required to assess the effect of allo-HSCT on adult AL with 11q23 abnormalities.

This study was designed to determine the optimal high dose for cytosine arabinoside (ara-C) in combination with fludarabine, granulocyte colony-stimulating factor, and mitoxantrone (FLAGM) in adult patients with relapsed or refractory acute myeloid leukemia. Nine patients were enrolled at increasing dosage levels of ara-C (8, 12, and 16 g/m2 per dose level). Ara-C and fludarabine were administered once a day at level 1, once or twice a day at level 2, and twice a day at level 3. All patients had grade 4 hematologic toxicity. The most common adverse events were of grade 2 or less, with nausea and vomiting being the most common (6 events), followed by diarrhea (5 events), and rash (5 events). Of the 13 grade 3 nonhematologic toxicities reported, the 2 most common were febrile neutropenia (6 events) and disseminated intravascular coagulation (3 events). No early deaths were observed. FLAGM with high-dose ara-C was considered safe for patients, and the recommended dosage of ara-C in this study was 2 g/m2 every 12 hours for a total dose of 16 g/m2.

This study analysed the clinical outcome of salvage therapy consisting of aclarubicin (ACR) plus behenoyl cytarabine (BHAC) and prednisolone (PSL) for patients with acute myeloid leukemia (AML). ACR was administered at a dose of 13 mg/m2 per day for 14 days; BHAC, at 130 mg/m2 per day for 14 days; and PSL was administered orally at a dose of 60 mg/m2 per day for 5 days. Of 47 patients, 25 (53.2%) achieved CR. The CR rates of patients in whom induction failed was 55% and that of relapsed patients was 51.9%. Four patients received allogeneic hematopoietic stem cell transplantation after achieving CR. Five patients achieved long-term survival without relapse. The 10-year relapse-free and overall survival rates were 20% and 10.6%, respectively. ACR in combination with BHAC showed a substantial anti-leukemic efficacy in previously treated AML patients and the role of ACR and BHAC may be considered while devising strategies for AML treatments.

The relationship between the total dose of daunorubicin (DNR) in induction therapy and the treatment outcome were evaluated based upon individualized doses of DNR during induction therapy for patients with acute myeloid leukemia(AML). Ninety-two previously untreated adult AML patients admitted to our hospital were analyzed for the dose of DNR required for complete remission (CR), the CR rate, disease-free survival (DFS) and overall survival (OS). The induction therapy consisted of DNR (40 mg/m2/d, i.v., from D 1 until the marrow was hypoplastic), Ara-C, prednisolone, and/or 6-thioguanine. Eighty-three out of 92 patients were assessable. Sixty-three patients entered CR (76%), of whom 52 attained CR with the first course of induction therapy. The 10-year DFS and OS rates were 31.2% and 42.3%, respectively. The median total dose of DNR in the induction therapy was 280 mg/m2 (120-480 mg/m2), which was not influenced by initial WBC count, or FAB type. These results indicate that when the dose is linked to the observed tumor response, the optimal dose of DNR in the induction therapy is around 280 mg/m2 (40 mg/m2 x 7 times), which is higher than the conventional dose of 40-60 mg/m2 for 3 days. The higher dose of DNR in the induction therapy for adult AML should be selected when the feasibility of a new drug is evaluated in a randomized trial.

To evaluate the prognostic significance of CD7 expression in de novo acute myeloid leukemia (AML), we studied 63 patients with AML who had been admitted to our hospital between September 1989 and January 1996. Even of the patients were later eliminated from the study (9 due to insufficient surface marker analyses, and 2 due to early death). The remaining 52 patients (median age: 42.5 years) were evaluated for morphologic subtype, immunophenotypic classification, complete remission (CR), disease-free survival (DFS) and overall survival (OS). All 52 patients were grouped by the French-American-British classification system: 10 as M1, 16 as M2, 11 as M3, 8 as M4, 5 as M5, and 2 as M6. Ten of the patients expressed CD7 on their leukemia cells (positive rate > or = 25) and were classified as CD7(+)AML, with morphological subtypes as follows: 3 as M1, 6 as M2, and 1 as M3. Thirty-three of the 42 patients with CD7 + AML (78.6%) and 6 of the 10 patients with CD7 + AML (40%) achieved CR. DFS and OS rates for the patients with CD7(+)AML were 22.1% and 35.4%, respectively; those for the CD7(+)AML patients were 53.3% and 44.4%, respectively. No significant differences in gender hematological findings, clinical manifestations such as hepatosplenomegaly, lymphadenopathy, or incidence of central nervous system involvement, CR rate, and DFS distinguished patients with CD7(+)AML from those with CD7(+)AML. These suggest that CD7 expression is unlikely to be a prognostic factor in AML.

Purpose: To evaluate the relationship of total-dose of daunorubicin (DNR) to the induction therapy and treatment outcome, we have administered individualized doses of DNR during induction treatment to patients with acute myelogenous leukemia (AML)., Patients and Methods: Ninety-two previously untreated adult patients with AML who entered our hospital were analyzed for the dose of DNR required to achieve complete remission (CR), the CR rate, disease-free survival (DFS), and overall survival (OS). Induction therapy consisted of DNR 40 mg/m2 daily intravenously from day 1 until the marrow was hypoplastic, cytarabine (Ara-C), prednisolone (PRD), and/or 6-thioguanine (6-TG)., Results: Eighty-three of 92 patients with adult AML were assessable for this study. Sixty-three (76%) patients achieved CR. Fifty-two of 63 CR patients achieved the CR in the first course of induction therapy, and 11 patients required the second course of induction therapy. The 5-year and 10-year DFS rates were 31.2% and 5-year and 10-year OS rates were 45.1% and 42.3%, respectively. The median total dose of DNR in the induction therapy was 280 mg/m2 (120 to 480 mg/m2). DNR dose did not influence the response to therapy and was not influenced by the initial WBC count or French-American-British (FAB) system classification., Conclusion: These results indicated that when the dose was linked to observed tumor response, the optimal dose of DNR in the induction therapy was approximately 280 mg/m2 (40 mg/m2 for 7 days), which is greater than the conventional dose of 40 to 60 mg/m2 for 3 days.