Randomized comparison of fixed-schedule versus response-oriented individualized induction therapy and use of ubenimex during and after consolidation therapy for elderly patients with acute myeloid leukemia: the JALSG GML200 Study.

We conducted a multicenter prospective randomized study to compare a fixed-scheduled induction therapy with a response-oriented individualized induction therapy for elderly patients with acute myeloid leukemia (AML). Newly diagnosed AML patients, aged between 65 and 80, were randomly assigned to receive fixed or individualized induction. Both groups received daunorubicin (DNR) 40 mg/m(2) for 3 days and behenoyl cytarabine (BHAC) 200 mg/m(2) for 8 days. In the individualized group, bone marrow biopsy was done on days 8 and 10, and according to the cellularity and blast ratio, the patients received additional DNR and BHAC for two to four more days. All patients achieving complete remission (CR) were randomized a second time to determine whether they would receive ubenimex. CR was obtained in 60.1 % of the fixed group and 63.6 % of the individualized group. Predicted 4-year relapse-free survival (RFS) was 9 % for the fixed group and 18 % for the individualized group. There were no statistically significant differences in CR and RFS between the fixed and individualized groups. In the ubenimex group, prolonged RFS was observed. Notably, gender was a prognostic factor in this study, as 102 female patients had a significantly higher CR rate (72.5 vs. 54.3 %, p = 0.0048) and better OS (24 vs. 14 % at 4 years, p = 0.018), compared with 140 male patients.

Long-term outcome following imatinib therapy for chronic myelogenous leukemia, with assessment of dosage and blood levels: the JALSG CML202 study.

A prospective multicenter Phase II study was performed to examine the efficacy and safety of imatinib therapy in newly diagnosed Japanese patients with chronic-phase CML. Patients were scheduled to receive imatinib 400 mg daily. Plasma imatinib concentrations were measured by liquid chromatography-tandem mass spectrometry. In 481 evaluable patients, estimated 7-year overall survival (OS) and event-free survival (EFS) at a median follow-up of 65 months were 93% and 87%, respectively. Because imatinib dosage was reduced in many patients due mainly to adverse events, subgroup analysis was performed according to the mean daily dose during the first 24 months of treatment: ≥360 mg (400-mg group; n = 294), 270-359 mg (300-mg group; n = 90) and <270 mg (200-mg group; n = 67). There were no significant differences in OS and EFS between the 300- and 400-mg groups; however, cumulative rates of complete cytogenetic and major molecular responses differed significantly between the two groups. There were no significant differences in mean imatinib trough levels between these two groups for the patients in whom trough levels had been measured. Survival and efficacy in the 200-mg group were markedly inferior to the former two groups. These results suggest that, although a daily dose of 400 mg imatinib is associated with better outcomes, 300 mg imatinib may be adequate for a considerable number of Japanese patients who are intolerant to 400 mg imatinib. Blood level monitoring would be useful to determine the optimal dose of imatinib.

Comparative quantitative analysis of BCR-ABL transcripts with the T315I mutant clone by polymerase chain reaction (PCR)-Invader method.

Drug resistance is a serious complication in the treatment of chronic myeloid leukemia (CML). The most common and best-characterized mechanism of secondary imatinib resistance in CML is the development of kinase domain mutations in the BCR-ABL gene. Second-generation tyrosine kinase inhibitors, such as dasatinib or nilotinib, overcome most of these mutations, but they are not effective against the T315I mutant. To determine whether these mutations contribute to clinical resistance, it is necessary to monitor the ratio of the mutant and wild-type forms. Here, we developed a polymerase chain reaction (PCR)-Invader assay for comparative quantitative analysis (qPI assay) of BCR-ABL transcripts with the T315I mutant clone. T315I ratios were calculated for the wild-type and mutant fold-over-zero (FOZ) values. In examination with 2 kinds of plasmids containing wild-type or T315I mutant PCR amplicons, mutant FOZ values were detected down to 1% of the total. The results of 12 serial samples from 2 patients (case A: Philadelphia-positive acute lymphoblastic leukemia and case B: CML) with the T315I mutant clone were compared with those of direct sequencing or 2 kinds of allele-specific oligonucleotide (ASO)-PCR. All samples showed the T315I mutation by qPI assay and ASO-PCR, and 10 samples showed it by direct sequencing. Significant correlation (correlation coefficient; r2 = 0.951) was noted between the qPI assay and quantitative ASO-PCR to analyze T315I mutant ratios. Thus, the qPI assay is a useful method for evaluating the T315I mutant clone in BCR-ABL transcripts.

Randomized study of induction therapy comparing standard-dose idarubicin with high-dose daunorubicin in adult patients with previously untreated acute myeloid leukemia: the JALSG AML201 Study.

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.

A randomized comparison of 4 courses of standard-dose multiagent chemotherapy versus 3 courses of high-dose cytarabine alone in postremission therapy for acute myeloid leukemia in adults: the JALSG AML201 Study.

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.

Intensified consolidation therapy with dose-escalated doxorubicin did not improve the prognosis of adults with acute lymphoblastic leukemia: the JALSG-ALL97 study.

We designed a treatment protocol for newly diagnosed adult acute lymphoblastic leukemia (ALL) in the pre-imatinib era, employing intensified consolidation therapy with a total of 330 mg/m² doxorubicin and adopting slightly modified induction and maintenance regimen of the CALGB 8811 study. Of 404 eligible patients (median age 38 years, range 15-64 years), 298 (74%) achieved complete remission (CR). The 5-year overall survival (OS) rate was 32%, and the 5-year disease-free survival (DFS) rate was 33%. Of 256 Philadelphia chromosome (Ph)-negative patients, 208 (81%) achieved CR and the 5-year OS rate was 39%, and 60 of them underwent allogeneic-hematopoietic stem cell transplantation (allo-HSCT) from related or unrelated donors during the first CR, resulting in 63% 5-year OS. Of 116 Ph-positive patients, 65 (56%) achieved CR and the 5-year OS rate was 15%, and 22 of them underwent allo-HSCT from related or unrelated donors during the first CR, resulting in 47% 5-year OS. In Ph-negative patients, multivariate analysis showed that older age, advanced performance status and unfavorable karyotypes were significant poor prognostic factors for OS and higher WBC counts for DFS. The present treatment regimen could not show a better outcome than that of our previous JALSG-ALL93 study for adult ALL.

Randomized trial of response-oriented individualized versus fixed-schedule induction chemotherapy with idarubicin and cytarabine in adult acute myeloid leukemia: the JALSG AML95 study.

A multicenter, prospective, randomized study was conducted to compare a response-oriented individualized remission induction therapy with a standard fixed-schedule induction therapy, using idarubicin (IDR) and cytarabine (Ara-C), in adult patients with acute myeloid leukemia (AML). Newly diagnosed patients with AML of age less than 65 were randomly assigned to receive either of the two schedules. Both groups received IDR (12 mg/m2) for 3 days and Ara-C (100 mg/m2) for 7 days. In the individualized group, if the bone marrow on day 8 did not become hypocellular with less than 15% blasts, patients received additional IDR for one more day and Ara-C for 2 or 3 more days. Patients achieving complete remission (CR) received the same post-remission therapy. The CR rate was 79.4% for the individualized group (n = 209) and 81.9% for the fixed group (n = 221) (p = 0.598). At a median follow-up of 81 months, 7-year predicted overall survival was 37% for the individualized group and 39% for the fixed group (p = 0.496), and 7-year predicted event-free survival was 22% for the individualized group and 23% for the fixed group (p = 0.546). Thus, the present study could not demonstrate any advantage of a response-oriented individualized induction therapy over a fixed-schedule induction therapy in this protocol setting.

Allogeneic stem cell transplantation versus chemotherapy as post-remission therapy for intermediate or poor risk adult acute myeloid leukemia: results of the JALSG AML97 study.

We prospectively compared allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chemotherapy as a post-remission therapy in a multicenter trial (JALSG AML97) of adult patients with intermediate or poor risk acute myeloid leukemia (AML). Of 503 patients aged 15-50 years old registered between December 1997 and July 2001, 392 achieved complete remission (CR). CR patients classified in the intermediate or poor risk group using a new scoring system were tissue typed. Seventy-three with and 92 without an HLA-identical sibling were assigned to the donor and no-donor groups. Of 73 patients in the donor group, 38 (52%) received allo-HSCT during CR1 and 17 (23%) after relapse. Intention-to-treat analysis revealed that the relapse incidence was reduced in the donor group (52 vs. 77%; p = 0.008), and the disease-free survival (DFS) improved (39 vs. 19%; p = 0.016), but overall survival (OS) was not significantly different (46 vs. 29%; p = 0.088). The OS benefit was seen in the patients aged 36-50 years old (49 vs. 24%; p = 0.031), suggesting an advantage of allo-HSCT among older patients with leukemia that is more resistant to chemotherapy than that among younger patients.

Comparative analysis of remission induction therapy for high-risk MDS and AML progressed from MDS in the MDS200 study of Japan Adult Leukemia Study Group.

A total of 120 patients with high-risk myelodysplastic syndrome (MDS) and AML progressed from MDS (MDS-AML) were registered in a randomized controlled study of the Japan Adult Leukemia Study Group (JALSG). Untreated adult patients with high-risk MDS and MDS-AML were randomly assigned to receive either idarubicin and cytosine arabinoside (IDR/Ara-C) (Group A) or low-dose cytosine arabinoside and aclarubicin (CA) (Group B). The remission rates were 64.7% for Group A (33 of 51 evaluable cases) and 43.9% for Group B (29 out of 66 evaluable cases). The 2-year overall survival rates and disease-free survival rates were 28.1 and 26.0% for Group A, and 32.1 and 24.8% for Group B, respectively. The duration of CR was 320.6 days for Group A and 378.7 days for Group B. There were 15 patients who lived longer than 1,000 days after diagnosis: 6 and 9 patients in Groups A and B, respectively. However, among patients enrolled in this trial, intensive chemotherapy did not produce better survival than low-dose chemotherapy. In conclusion, it is necessary to introduce the first line therapy excluding the chemotherapy that can prolong survival in patients with high-risk MDS and MDS-AML.

Epidemiologic study on survival of chronic myeloid leukemia and Ph(+) acute lymphoblastic leukemia patients with BCR-ABL T315I mutation.

The BCR-ABL T315I mutation represents a major mechanism of resistance to tyrosine kinase inhibitors (TKIs). The objectives of this retrospective observational study were to estimate overall and progression-free survival for chronic myeloid leukemia in chronic-phase (CP), accelerated-phase (AP), or blastic-phase (BP) and Philadelphia chromosome-positive (Ph)(+) acute lymphoblastic leukemia (ALL) patients with T315I mutation. Medical records of 222 patients from 9 countries were reviewed; data were analyzed using log-rank tests and Cox proportional hazard models. Median age at T315I mutation detection was 54 years; 57% cases were men. Median time between TKI treatment initiation and T315I mutation detection was 29.2, 15.4, 5.8, and 9.1 months, respectively, for CP, AP, BP, and Ph(+) ALL patients. After T315I mutation detection, second-generation TKIs were used in 56% of cases, hydroxyurea in 39%, imatinib in 35%, cytarabine in 26%, MK-0457 in 11%, stem cell transplantation in 17%, and interferon-alpha in 6% of cases. Median overall survival from T315I mutation detection was 22.4, 28.4, 4.0, and 4.9 months, and median progression-free survival was 11.5, 22.2, 1.8, and 2.5 months, respectively, for CP, AP, BP, and Ph(+) ALL patients. These results confirm that survival of patients harboring a T315I mutation is dependent on disease phase at the time of mutation detection.

[Correlation of quantification of major bcr-abl mRNA between TMA (transcription mediated amplification) method and real-time quantitative PCR].

Imatinib mesylate has significantly improved the outcome of patients with CML. In the IRIS trial, major molecular response (MMR), which is defined as the achievement of > or =3 log reduction in bcr-abl mRNA from the standardized baseline, was observed in 40% of CML patients by 12 months. Achievement of an MMR at 18 months is associated with 100% probability of transformation-free survival at 60 months, and MMR is an important goal of therapy. The nucleic acid quantitative "DNA probe FR Amp-CML" kit based on the transcription-mediated amplification method, can measure major bcr-abl mRNA in peripheral blood leukocytes. In this study, we studied the clinical usefulness of Amp-CML for monitoring minimum residual disease by comparison with the European standard nucleic acid quantitative method and real-time quantitative PCR (RQ-PCR) with GAPDH as an internal control, using peripheral leukocytes obtained from patients receiving imatinib treatment. The results indicated that Amp-CML had a significant correlation with Fusion Quant M-BCR (R>0.971, P<0.01), a standard nucleic acid quantitative method used in Europe and RQ-PCR (R>0.974, P<0.01), especially in samples with more than 100 copies/microg RNA of major bcr-abl mRNA. These data suggest that Amp-CML is reliable for monitoring major bcr-abl mRNA in patients having achieved an MMR.

Cas-L was overexpressed in imatinib-resistant gastrointestinal stromal tumor cells.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the gastrointestinal tract. Most GISTs patients respond to imatinib, yet will eventually exhibit resistance, and the mechanisms of imatinib resistance have not yet been fully elucidated. To clarify the mechanisms of secondary imatinib-resistant gastrointestinal stromal tumors, we generated resistant cells from the imatinib-sensitive GIST-T1 cells by exposing them to increasing concentrations of imatinib for 6 m. GIST-T1 IR (imatinib-resistant) cells showing an IC50 of imatinib 5-7 microM were generated. In GIST-T1 IR cells, KIT and its downstream signaling molecules remained phosphorylated with the presence of 1 microM imatinib, and no new mutations were found in KIT, PDGFRA, PKCtheta and JAK2. DNA micro-array analysis showed the overexpression of Cas-L in the resistant cells with 513 fold higher than that in the parental cells. Cas-L overexpression and SRC hyper-activation were also observed in the resistant cells at protein level and they were markedly decreased in KIT siRNA transfected GIST-T1 IR cells. Interestingly, GIST-T1 IR cells transfected with Cas-L siRNA turned out to become again sensitive to imatinib. Imatinib or PP1, a SRC inhibitor, alone was not enough to suppress the activation of KIT and its downstream signaling molecules, but the combination of them showed strong inhibitory effects on those in the resistant cells. We report for the first time that the mechanism of imatinib-resistant GISTs, at least in one cell line, involves KIT/Cas-L/SRC signaling. Cas-L depletion sensitized the resistant GIST-T1 IR cells to imatinib.

Prospective monitoring of BCR-ABL1 transcript levels in patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia undergoing imatinib-combined chemotherapy.

The clinical significance of minimal residual disease (MRD) is uncertain in patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph+ ALL) treated with imatinib-combined chemotherapy. Here we report the results of prospective MRD monitoring in 100 adult patients. Three hundred and sixty-seven follow-up bone marrow samples, collected at predefined time points during a uniform treatment protocol, were analysed for BCR-ABL1 transcripts by quantitative reverse transcription polymerase chain reaction. Ninety-seven patients (97%) achieved complete remission (CR), and the relapse-free survival (RFS) rate was 46% at 3 years. Negative MRD at the end of induction therapy was not associated with longer RFS or a lower relapse rate (P = 0.800 and P = 0.964 respectively). Twenty-nine patients showed MRD elevation during haematological CR. Of these, 10 of the 16 who had undergone allogeneic haematopoietic stem cell transplantation (HSCT) in first CR were alive without relapse at a median of 2.9 years after transplantation, whereas 12 of the 13 who had not undergone allogeneic HSCT experienced a relapse. These results demonstrate that, in Ph+ ALL patients treated with imatinib-combined chemotherapy, rapid molecular response is not associated with a favourable prognosis, and that a single observation of elevated MRD is predictive of subsequent relapse, but allogeneic HSCT can override its adverse effect.

Clinical features of adult acute leukemia with 11q23 abnormalities in Japan: a co-operative multicenter study.

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.

Karyotype at diagnosis is the major prognostic factor predicting relapse-free survival for patients with Philadelphia chromosome-positive acute lymphoblastic leukemia treated with imatinib-combined chemotherapy.

To identify factors associated with relapse-free survival (RFS), 80 patients with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia, enrolled in a phase II study of imatinib-combined chemotherapy, were analyzed. The median follow-up of surviving patients was 26.7 months (maximum, 52.5 months). Twenty-eight out of 77 patients who had achieved CR relapsed. The probability of RFS was 50.5% at 2 years. Multivariate analysis revealed that the presence of secondary chromosome aberrations in addition to t(9;22) at diagnosis constitute an independent predictive value for RFS (p=0.027), and increase the risk of treatment failure by 2.8-fold.

A novel gene, ANKRD28 on 3p25, is fused with NUP98 on 11p15 in a cryptic 3-way translocation of t(3;5;11)(p25;q35;p15) in an adult patient with myelodysplastic syndrome/acute myelogenous leukemia.

We identified a novel gene fusion of ANKRD28 (ankyrin repeat domain 28) on 3p25 to NUP98 on 11p15 in a patient with adult myelodysplastic syndrome/acute myelogenous leukemia. A partially cryptic 3-way translocation, t(3;5;11)(p25;q35;p15), that had initially been supposed to be t(3;5)(p25;q35) was revealed by precise breakpoint mapping via fluorescence in situ hybridization analysis with bacterial artificial chromosome clones. This translocation produces the expression of 2 in-frame fusion transcripts, the novel ANKRD28-NUP98 and NUP98-NSD1, and 1 out-of-frame NSD1-ANKRD28 transcript. Transient overexpression of ANKRD28-NUP98 in NIH/3T3 cells, but not the C-terminal deletion mutant of ANKRD28 (DeltaC-ANKRD28), caused significantly increased focus formation compared with mock-transfectant controls. ANKRD28-NUP98 was localized in the nucleolus and cytoplasm, whereas ANKRD28 and DeltaC-ANKRD28 were found exclusively in the cytoplasm. Alteration of the subcellular localization of ANKRD28 might have contributed to the leukemogenesis in this case. This report is the first of ANKRD28 as an NUP98 fusion partner, and this case implies that this fusion may be responsible for hematologic malignancies.