Ph-positive Acute Lymphoblastic Leukemia Patients Research Articles

Comparison of Long-Term Outcome between Imatinib and Dasatinib Prophylaxis after Allogeneic Stem Cell Transplantation in Patients with Philadelphia-Positive Acute Lymphoblastic Leukemia-a Multi-Center Retrospective Study

Background: Though the prognosis of Philadelphia-positive (Ph-positive) acute lymphoblastic leukemia (ALL) has been improved since the introduction of tyrosine kinase inhibitors (TKIs) and combined with allogeneic stem cell transplantation (allo-HSCT), relapse after HSCT remains a concern. Prophylactic TKIs after allo-HSCT seemed a promising strategy to prevent relapse. But the optimal choice of the agent is still obscure.Methods: We retrospectively analyzed the clinical data of Ph-positive ALL patients who underwent allo-HSCT in CR1 from 6 medical centers in China between September 2010 and October 2021. Patients were divided into two cohorts according to different choice of TKI after allo-HSCT, namely Ima cohort with imatinib prophylaxis and Das cohort with dasatinib prophylaxis. Survival and safety outcomes of two cohorts were compared, and prognostic factors were determined by univariate and multivariate analyses.Results: One hundred and forty-one patients, with median age of 37 years (range, 14-61 years), were included, of whom 91 were in Ima cohort and 50 were in Das cohort. After median follow-up of 50.6 months, 5-year cumulative relapse rate (CIR), non-relapse mortality rate (NMR), leukemia-free time (LFS) and overall survival (OS) in Ima and Das cohort were 16.1% and 12.5%; 5.2% and 9.8%; 78.8% and 77.6%; 86.5% and 77.6%, respectively, with no significant difference. Mild cGVHD was higher in Das cohort compared to Ima cohort, while the total, moderate or severe cGVHD were similar. The most common adverse event was neutropenia (66.4%). Das cohort owned higher incidence of gastrointestinal bleeding and gastrointestinal reaction than Ima cohort. The proportion of patients treated on schedule was 30% in Das cohort, lower than that of in Ima cohort (p<0.001). Drug intolerance was the main reason for not completed treatment as intended.Conclusions: For patients with Ph-positive ALL receiving allo-HSCT in CR1, imatinib prophylaxis after transplantation could obtain the same long-term outcome compared to dasatinib, showing better tolerance.

Updated Outcomes in Adult Philadelphia-Positive Acute Lymphoblastic Leukemia Patients Using Tyrosine Kinase Inhibitors Combined with the Modified University of Southern California (USC ALL) Regimen without Peg-Asparaginase in the Era of Novel Agents

Introduction: Prior to the introduction of tyrosine kinase inhibitors (TKIs), the presence of BCR-ABL1 conferred a poor prognosis in patients with acute lymphoblastic leukemia (ALL). We published our analysis in 2017 comparing the survival of Ph-Positive (Ph+) and Ph-negative ALL patients during the period when TKIs were universally available in the United States for Ph+ ALL using a Surveillance, Epidemiology, and End Results (SEER) Database analysis, but despite using TKIs, we have continued to remain reliant on cytotoxic chemotherapy and allogenic hematopoietic stem cell transplant (allo-HSCT) to achieve the best long-term outcomes. However, with the introduction of more potent TKIs and other novel agents, and better methods for monitoring minimal residual disease (MRD), the best approach is yet to be determined. In this study we present updated data from our institution with incorporation of TKIs in our modified USC ALL pediatric-based regimen without PEG. Methods This retrospective, single institution chart review included adults aged 18 with newly diagnosed Ph+ ALL between 2016 and 2020. Primary objectives were Overall survival (OS) and event-free survival (EFS) at 3 years and secondary objectives were rates of complete remission/complete remission with incomplete recovery (CR/CRi), minimal residual disease (MRD) by flow cytometry and presence of BCR-ABL1 fusion transcript by real time polymerase chain reaction. Descriptive statistics of patients were reported and evaluated using Fisher's exact test. OS and EFS were reported through Kaplan Meier curves and Log-rank tests. Two-sided p value ≤0.05 considered significant. RESULTS: 25 Ph+ ALL patients were reviewed. Median age at diagnosis was 43.5 years with 44% males and 56% females in this study. Median BMI was 31.9 kg/ m2. Most patients were Hispanic at 84%, 12% White and 4% Asian.43.5% had hepatic steatosis and 4% had CNS disease pre-induction. After induction 1, 80% of patients achieved CR/CRi, 4% were refractory, and 50% were MRD negative by flow, with 24% of patients with undetectable BCR-ABL1 by PCR. After induction 2, 90.5% had achieved CR/CRi, none were refractory and 56.3% were MRD negative by flow with 32% of patients with undetectable BCR-ABL1 PCR. 48% of patients received blinatumomab for MRD flow positivity with a median of 3 cycles, none received inotuzumab. 44.4% underwent allo-HSCT, none were sent for CAR-T. Of note, 64% of patients received Dasatinib only, 0.04% received imatinib and 32% received at least 2 TKIs. Overall, 12% had known relapse, none were refractory, and 12.5% died. The 3y OS was 89.4%, 3y EFS and DFS was at 77%. When stratified by blinatumomab use, 3y OS was 87.5% vs 91.7% (p=0.49), 3y DFS was 80.2% vs 76.4% and 3y EFS was 80.2% vs 76.4% (p=0.8). When survival was stratified by transplant status, 3y OS with allo-HSCT was 100% vs 76.9% (p=0.048), 3y EFS/DFS with allo-HSCT was 100% vs 50.1% (p=0.033) (Fig 1-2). CONCLUSIONS: The use of the modified USC ALL regimen without PEG for the treatment of newly diagnosed Ph+ ALL combined with TKI continued to lead to a high 3-year OS at 89.4% and 3-year EFS and DFS at 77%. All patients received TKI, half of the patients received blinatumomab and received allo-HSCT which led to high OS, EFS and DFS even without PEG. This was statistically significant in those who were able to undergo allo-HSCT (3y OS/EFS/DFS 100% vs 76.9% OS/50.1% EFS/DFS) (p=0.033-0.048). This study further highlights the importance of allo-HSCT in Ph+ ALL patients who received TKI without PEG. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Predictive Model and Factors of Relapse after Allogeneic Stem Cell Transplantation in Adults with Ph-Positive Acute Lymphoblastic Leukemia

Background: Relapses after allo-HSCT remain an unsolved problem in Ph-positive acute lymphoblastic leukemia (ALL) patients, especially in patients with detectable BCR/ABL levels prior to allogeneic stem cell transplantation (allo-HSCT). Majority of centers make efforts to manage with it by preemptive or prophylactic administration of TKIs after allo-HSCT. However, the risk factors in this setting are yet to be determined. Moreover, persistence of minimal residual disease (MRD) after induction plays a critical role in relapse probability, but its fluctuation after transplant in the context of TKIs application is still a question. The aim of this study is to apply modern machine-learning approaches for building relapse predicting models and testing variable importance.Patients and methods: This study analyses the data in retrospective cohort of 74 Ph-positive ALL patients with posttransplant BCR/ABL expression levels available at different time intervals with median age of 30,5 years (range, 18-55), in whom allo-HSCT were performed between 2008 and 2021. Patient characteristics and features of the disease are presented in Table 1. For the analysis, all TKIs were divided into 2 groups TKIs1 - imatinib, TKIs2 - other TKIs, regardless of generation. Machine learning models were developed using R programming language and Caret package. The dependent variable was relapse after prediction moment, the following independent variable features were used: time intervals between allo-HSCT and prediction moment, BCR/ABL expression level at prediction moment, therapy after allo-HSCT (TKIs1 or TKIs2), the highest BCR/ABL expression level before prediction moment, chronic «graft-versus-host» disease (GvHD) before prediction for the patients, who reached D+100 after allo-HSCT.Results: At the time of analysis median follow-up was 26 months (range, 1-116). 5-year OS and EFS were 67,1% (95% CI 54,2 - 80) and 55,1% (95% CI 42,5 - 68,3), respectively, whereas 5-year cumulative incidence of relapse was 46,1% (95% CI 26,2 - 66) for MRD-positive prior to allo-HSCT patients, compared to 24,1% (95% CI 6,9-41,3) for MRD-negative patients (р=0,04).The resulting ROC-curve for 3 most effective classification models is given in figure 1A. As one can see Gradient Boosting Method (GBM) provided maximal AUC score (0.88). For this a decision-making threshold may be adjusted for obtaining Specificity = 0.75, Sensitivity = 0.88. Variable importance plot (figure 1B) showed that the highest BCR/ABL level, prediction moment, chronic GvHD and current BCR/ABL level have the strongest importance, while preceding therapy turned out to be less significant factor. In fact, exclusion of TKIs type almost did not affect the ROC curves. In GBM model AUC still demonstrated appropriate level of 0.87. When analyzing the model accuracy, false-negative rate (FNR) and false-positive rate (FPR) errors were estimated for the three ranges of prediction moments (figure 1C). It was shown that after D+100 both error rates don't exceed 22%, while before D+100 the model fails to make accurate prediction based on the independent variables used.Conclusions: Using independent factors, we built the model for both bone marrow and extramedullary relapses prediction after allo-HSCT with high sensitivity and reasonable specificity based on the relatively small group of patients. According to the predicting model, we confirm, that a high level of BCR/ABL at any time point after allo-HSCT is the most significant predictor of relapse, which may indicate the presence of subclones of cells that cause resistance to chemotherapy or TKIs. The BCR/ABL MRD levels before D+100 have low predictive ability for early relapses, which may develop rapidly without MRD phase. At the same time, BCR/ABL levels relatively accurate predict relapses after D+100 with ongoing TKI prophylaxis. The absence of chronic GvHD is an important independent factor influencing the risk of relapse. This means that for high-risk patients, approaches to induce a «graft-versus-leukemia» effect should be considered. In addition, prophylactic use of monoclonal antibodies in combination with TKIs may be considered to prevent relapse in the absence of chronic GvHD in high-risk patients. In summary, we believe that verification of this model on a multicenter group of patients is required to facilitate its clinical application. [Display omitted] DisclosuresKulagin: Pfizer: Speakers Bureau; Johnson & Johnson: Speakers Bureau; Alexion: Research Funding; Roche: Speakers Bureau; Novartis: Speakers Bureau; Generium: Speakers Bureau; Sanofi: Speakers Bureau; Apellis: Research Funding; Biocad: Research Funding; X4 Pharmaceuticals: Research Funding.

The Omission of High-Dose Cytarabine during Consolidation Therapy of Ph-Positive ALL Patients Treated with Nilotinib and Low-Intensity Chemotherapy Results in an Increased Risk of Relapses Despite Non-Inferior Levels of Late BCR-ABL1 MRD Response. First Results of the Randomized Graaph-2014 Study

The Omission of High-Dose Cytarabine during Consolidation Therapy of Ph-Positive ALL Patients Treated with Nilotinib and Low-Intensity Chemotherapy Results in an Increased Risk of Relapses Despite Non-Inferior Levels of Late BCR-ABL1 MRD Response. First Results of the Randomized Graaph-2014 Study

Persistence of the Minimal Residual Disease at the End of Induction Is Not a Factor of Poor Prognosis If Imatinib Was Changed to the Dasatinib By Ph+ RALL Protocol in Ph-Positive Acute Lymphoblastic Leukemia Patients

Introduction. The role of minimal residual disease (MRD) has been confirmed as a clear prognostic factor by some big studies in Ph-positive acute lymphoblastic leukemia (Ph+ ALL) patients. The persistent MRD positivity may be indicative of the emergence of resistant mutations and TKI therapy should therefore be changed in these patients according to the sensitivity. Ph+ RALL protocol suggests that if a patient does not achieve the major molecular complete remission (MolCR) at day +70, Imatinib should be changed to Dasatinib for subsequent therapy. Could the change of Imatinib to Dasatinib in cases with MRD persistence at the end of induction improve the prognosis of the Ph+ ALL patients? It hasn't been described yet.Aim. To evaluate the role MRD persistence at the end of induction (day +70) in Ph+ ALL patients treated by Ph+ RALL protocol.Patients and treatment. From 2010 January to 2017 July, 36 new Ph+ ALL cases were diagnosed in 3 centers of the RALL-group (median age 35 years (17-68), m/f 19(53%)/17(47%), CNS disease=1, WBC> 30*109/l= 16(44%), bcr/abl transcript p190/p210/p190+210 21(59%)/8(22%)/7(19%)). All patients were treated according to RALL protocol with parallel administration of Imatinib. This protocol is based mainly on 600 mg Imatinib with prednisolone, VNCR, L-asp, followed by 6-MP and MTX. Imatinib had to be substituted by Dasatinib (140 mg) after non-achievement of MolCR on day 70 of treatment. MolCR was stated if bcr/abl chimeric transcript was <0,01% by PCR with 10-4 sensitivity. All patients were considered as candidates for allogeneic HSCT if HLA-identical donor was available. 16 pts (44%) underwent HSCT in the first-line therapy: 2 (12,5%) autologous, 4 (25%) matched related and 10 (62,5%) matched unrelated.Results. Hematological complete remission (CR) was achieved in 32 (89%) of 36 pts (except two early deaths and 2 refractory cases). On day 70 MolCR was achieved in 18 (56%) of 32 pts. Death on therapy (within 3 months of induction/consolidation) was registered in 4 (11%) cases, in 2 patients of them after day 70th of the protocol in CR. The major issue is the non-relapsed mortality after unrelated allo-HSCT (n=3, aGVHD and severe infections, at a median +4 months after HSCT).The 5-y overall survival (OS) and disease-free survival (DFS) for all 36 pts was 56% and 47%, respectively.The 5-y OS was 65% vs 51% (p=0,35), and DFS was 49 vs 48% (p=0,9) in MRD-negative and MRD-positive patients on day 70th of the protocol (Picture). In a univariate analysis for Ph+ ALL patients the fulfilled of HSCT in the first-line therapy became statistically significant for DFS. The 5-y OS was 65% vs 48% (p=0,07), and DFS was 60% vs 32% (p=0,01) in transplanted vs non-transplanted patients by Kaplan-Meier analysis.Conclusions. We didn't revealany difference in efficiency of the therapy in Ph+ RALL protocol according to the MRD status at the day 70. We attribute the absence of the effect of MRD status after induction on the results of treatment, to the shift to Dasatinib (140 mg) after non-achievement of MolCR on day 70. The performance of HSCT in the first-line therapy reliably improved the efficacy in Ph-positive ALL patients on RALL protocol. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Outcome of BCR-ABL/Philadelphia Positive Acute Lymphoblastic Leukemia: A Single Centre Experience from Developing Country

Introduction : Philadelphia (Ph) positive Acute Lymphoblastic Leukemia (ALL) is an aggressive type of leukemia and is uniformly associated with an unfavorable outcome when treated with standard chemotherapy. Current treatment of Ph positive ALL comprises of standard systemic and CNS directed chemotherapy along with tyrosine kinase inhibitor (TKIs) to achieve molecular response followed by Allogeneic stem cell transplantation (Allo-SCT). We aim to present the clinical profile and outcomes of Ph + ALL patients treated at our centre.Material and Methods : This is a retrospective study where medical records of 248 patients who were diagnosed and treated for ALL from 1-Jan-2011 to 30-Jun-2016 at our centre were analyzed. Out of those 248 patients, 51 patients (20.5%) were Ph chromosome or BCR-ABL positive and were eligible for the study. Medical records were reviewed and information regarding patient profile, disease characteristics and treatment were collected. Probabilities of Event Free Survival (EFS) was calculated using the Kaplan Meier estimate; the log rank test was used for univariate comparison. A p-value <0.05 was considered to be significant. All statistical analyses were performed using Statistical Package for Social Sciences (SPSS 20, IBM SPSS Statistics for Windows, version 20.0; IBM Corp., Armonk, NY, USA).Results : Out of 51 Ph positive ALL patients, 44 patients were started on treatment and were included in this study. Twenty five (57%) were males; median age of the patients was 35yrs (14-76yrs). Median WBC count was52.3 x 103/mm3 (0.7-432.4 x 103/mm3), 5 patients were CNS 3 while rest were CNS 1. Cytogenetic information was available for 35 patients, out of whom 28 patients had Ph chromosome with 16 patients having additional cytogenetic abnormality. All patients were BCR-ABL positive. Induction chemotherapy was given in all 44 patients. Post induction 40 patients achieved complete remission (CR) while one patient achieved CR after salvage chemotherapy, 2 patients were induction failure and 1 patient died during induction due to fungal pneumonia. Molecular responses were assessed in 26 patients, 11 (42%) achieved major molecular remission (MMR). Thirty eight patients went on to receive consolidation therapy with chemotherapy with TKI (n=24) or chemotherapy with TKI followed by Allo-SCT (n=14).For allo-SCT (matched sibling donor n=10 with Myeloablative conditioning n=8 and reduced intensity conditioning (RIC) n=2, haplo-identical donor transplant n=4 with non-myeloablative conditioning n=3 and RIC n=1),commonly used regimes were TBI based in 9/14 patients. Six patients experienced acute GvHD of grade II-IV and 7 patients developed chronic GvHD (extensive chronic GvHD in 1 patient). One patient died in the peri-transplant period (D+14) due to klebsiella sepsis. A total of 10 episodes of CMV reactivations were seen. Among other infections seen in post transplant patients were 1 patient each with pulmonary tuberculosis, esophageal tuberculosis, fungal pneumonia and herpes-zoster. Mortality 6/14 including one relapse mortality and 5 TRM with EFS of 57% at median follow up of 16 months (3-49 mo).Out of 24 patients on chemotherapy with TKI, 8 patients are in complete remission, while 5 patients defaulted, 11 patients relapsed with subsequent salvage therapy and Allo-SCT in 6 patients but ultimately death in all 11 patients with EFS of 42% (8/19, after excluding defaulted patients) at median follow up of 12 months (1-45 mo).On comparing patients that underwent Allo-SCT versus those that received only chemotherapy, it was found that the two groups were comparable except for age (Table - 1). Median age was higher in the chemotherapy alone group. No statistically significant difference in EFS was found in patients who underwent Allo-SCT vs chemotherapy alone (57% vs 42%, p= 0.845). (Figure 1)Conclusion : Allo-SCT can improve the survival of Ph positive ALL patients. There is a need to conduct a prospective randomized study with large number of patients to clearly define the beneficial role of Allo-SCT in this era of universal TKI usage. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Different Clinical Implications of Kinase Domain BCR-ABL1 Variants Detected in Chronic Myeloid Leukemia and Acute Lymphoblastic Leukemia Patients

Background: Kinase domain (KD) mutations is a common resistance mechanism, secondary to the tyrosine-kinase inhibitors (ITKs) treatment in the case of chronic myeloid leukemia (CML) and Philadelphia (Ph)-positive acute lymphoblastic leukemia (ALL) patients. Sanger sequencing is the gold standard technique and already the currently recommended method for BCR-ABL1 KD mutation detection. However, Sanger sequencing has limited sensitivity and cannot firmly identify populations with variant allele frequencies (VAF) &lt; 15-20%. Next-generation sequencing (NGS) allow us the screening of mutations in the whole KD with variants with a VAF greater than 1%. The aim of this study is to evaluate the clinical and prognostic implications of CML and Ph-positive ALL patients who have been studied for mutations in BCR-ABL1 by NGS. Methods: Seventy CML and Ph-pos ALL patients have been studied for BCR-ABL1 mutations between years 2015-2017. The study reason was warning or failure according to European Leukemia Net recommendations in the case of CML patients, and diagnostic or relapse in the case of ALL patients. Clinical characteristics of the patients are depicted on Table 1. Categorical variables are described as frequency, and quantitative variables as medians. Contingency tables were used to analyze associations between categorical variables (χ2). Median test was used to compare medians of continuous variables between groups. Overall survival (OS) was estimated using the Kaplan-Meier method and compared between patients using the log-rank test. Results: We have found 37 patients with mutations (51%), the most frequent being p.T315I, p.L248V and p.L387M. 28 out of 59 were found in CML (47%) vs 9 out of 13 (69%) in ALL. Of the 37 patients with mutations, double mutations have been found 10 times (27%). In the 72 analyses performed, 62 mutations were found in total, 41 of them were variants of uncertain significance (VUS) and 21 were well-known mutation. The median levels of BCR-ABL1 (IS) at the time of analysis were 3.00 (0.01-196.18) %. Regarding CML patients, we have found 12 and 16 cases with pathogenic mutations and VUS, respectively. The mean survival for CML and ALL were 75.2 months (CI 95%, 65.7-84.6) and 24.7 months (13.3-36.2), respectively. There are significant differences between the overall survival curves for patients with CML who have mutations in BCR-ABL1 compared to those who have VUS or do not (p-value = 0.024, n=59), suggesting a second role of the VUS variants in the resistance of the patients to the TKI. These two groups have no significant differences in ALL patients (p-value= 0.32, n=13). Overall survival at 10 years from the date of diagnosis is 74% for CML patients with mutations and 90% for CML patients without mutations. Data dropped significantly for ALL patients, but the number of cases is too low. Conclusions: - Mutations have been identified in 47% of CML patients studied in the case of failure or warning and 69% of the patients of ALL at diagnosis or relapse moments. - The identification of pathogenic variants has poor prognosis in patients with CML (p = 0.024), however no differences were observed in ALL. - The identification of VUS is not associated to poor prognosis and these variants could not confer resistance to ITK. Disclosures Sevilla: Rocket Pharmaceuticals, Inc.: Honoraria, Patents &amp; Royalties: Inventor on patents on lentiviral vectors filled by CIEMAT, CIBERER and F.J.D and may be entitled to receive financial benefits from the licensing of such patents; NOVARTIS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Rocket: Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sobi: Membership on an entity's Board of Directors or advisory committees; Miltenyi Biotech: Honoraria. Steegmann:Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. García Gutiérrez:Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Incyte: Honoraria, Research Funding.

Prevalence and Clinical Outcome of Philadelphia-Like Acute Lymphoblastic Leukemia: Systematic Review and Meta-analysis

BackgroundThe presence of Philadelphia (Ph)-like ALL among patients with acute lymphoblastic leukemia (ALL) may indicate a poor prognosis similar to Ph+ ALL, although the data are still inconclusive and the prevalence of Ph-like ALL varied considerably across studies. Patients and MethodsWe performed a systematic review and meta-analysis in order to identify all cohort studies of patients with ALL that reported the prevalence of Ph-like ALL and to summarize their results together. The pooled prevalence and rate were calculated by the DerSimonian-Laird random-effect model with double arcsine transformation. ResultsAcross the 15 included studies describing 11,040 ALL patients, the peak prevalence of the presence of Ph-like ALL among patients with ALL was between ages 11 and 40 years, where the pooled prevalence was 25.8% to 26.2%. The pooled 5-year overall survival rate of Ph-like ALL was 42.8% (95% confidence interval, 23.9-64.1; I2 93%). Comparative analysis with B-other ALL patients was conducted by the Mantel-Haenszel method; it found that Ph-like ALL patients had a significantly lower chance of being alive at 5 years (pooled odds ratio, 0.35; 95% confidence interval, 0.25-0.50; P < .00001, I2 = 40%). The chance of Ph-like ALL patients surviving at 5 years was similar to Ph-positive ALL patients (pooled odds ratio, 0.72; 95% confidence interval, 0.26-2.02; P = .53, I2 = 77%). ConclusionPh-like ALL is not uncommon among ALL patients, and its presence is associated with an unfavorable outcome. More investigations are needed for better therapeutic options.

Current treatment strategies for Philadelphia chromosome-positive adult acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is an aggressive hematological disease. The incorporation of tyrosine kinase inhibitors (TKIs) into the standard treatment regimen for Philadelphia (Ph)-positive ALL significantly improved clinical outcomes. TKI-based induction chemotherapy, followed by allogeneic hematopoietic cell transplantation (HCT) during the first complete remission (CR), is the standard of care for ALL patients. However, treatment with TKIs alone or TKIs plus low-intensity chemotherapy can achieve CR in some patients. Although this strategy is not enough to induce a deeper molecular response, it can reduce the incidence of treatment-related mortality. Despite promising results from pediatric trials, allogeneic HCT remains an important component of the treatment strategy for Ph-positive adult ALL. However, improving the highly sensitive BCR-ABL1 assays and introducing immunotherapy may decrease the demand for allogeneic HCT. Nevertheless, the treatment of Ph-positive ALL is still challenging, especially in cases with relapsed and refractory disease. Potent TKIs and monoclonal antibodies, such as blinatumomab and inotuzumab, have improved patient outcomes in relapse and refractory cases of ALL. The introduction of effective agents, such as potent TKIs and monoclonal antibodies, may improve the possibility of remission in Ph-positive ALL patients and hopefully cure this disease.

Clinical Significance of Clonal Cytogenetic Heterogeneity (CCH) at Diagnosis in Adult Patients with Acute Lymphoblastic Leukemia (ALL)

Background:Although cytogenetic abnormalities at diagnosis are recognized as one of the most potent prognostic factors in acute leukemia patients, CCH acquisition at diagnosis, which are considered as a result of clonal evolution of leukemia cells, is not taken into account in prognostic classifications. Recent studies reported that CCH acquisition was observed in 24 - 32% of adult AML patients with abnormal karyotype, was more likely to occur in patients with older age and complex karyotype, and showed adverse prognostic impact. However, the clinical significance of CCH acquisition has not been investigated in adult ALL patients to date. Patients and methods: Of the 238 adult ALL patients diagnosed between 1990 and 2016, 120 patients with abnormal karyotype at diagnosis, who underwent intensive chemotherapy, were included in this study. CCH was defined as presence of two or more cytogenetically abnormal clones. A defined ancestral clonal evolution included either mother-daughter and/or branched patterns. In the mother-daughter pattern, a daughter clone showed all cytogenetic abnormalities of a mother clone plus additional abnormality(s), which define a distinct subclone. In a branch pattern, all subclones possessed common cytogenetic abnormalities suggesting presence of a common ancestry, but each subclone acquires unique additional abnormality(s), which define them as distinctive subclones. Both patterns of cytogenetic clonal evolution were sometimes seen in a patient. Composite karyotypes were applied to patients where a common ancestry could not be clearly determined because of too complicated cytogenetic findings. Fisher's exact test was used to compare binary variables. The logistic regression model was used for multivariate analysis of predisposing factors. Overall survival (OS) was estimated with the Kaplan-Meier method and compared using the log-rank test. The Cox proportional hazard model was used for multivariate analysis of prognostic factors. Values of p < 0.05 were considered to indicate statistical significance. Results:Of the 120 patients included in this study, 64 patients were male, and 56 were female. The median age was 50 years (range, 16-79 years). Karyotypes at diagnosis were Philadelphia chromosome (Ph) in 56 patients, complex in 15, and t(8;14) in seven. According to the definition described above, 47 patients (39%) showed CCH at diagnosis, and two (4%) among them were categorized as composite karyotype. Of the 45 patients harboring a defined ancestral clonal evolution, numbers of subclones were two, three, and four in 32 patients (68%), 11 (24%), and 2 (4%), respectively. Mother-daughter pattern, branched pattern, and both were seen in 34 patients (76%), 5 (11%), and 6 (13%). In univariate analysis for predisposing factors of CCH acquisition, only younger age was significantly associated with CCH acquisition (48% in age <= 50 vs. 29% in age > 50; p = 0.04), but not karyotype. This statistical significance was confirmed with multivariate analysis (odds ratio = 0.44; p = 0.03). When investigating the prognostic impact of CCH acquisition, patients were divided into Ph-negative or Ph-positive ALL groups. In the 64 Ph-negative ALL patients, the CR rates were not significantly different between patients with or without CCH (78% vs. 78%, respectively; p = 1.00). The OS rates were similar between two groups (26% vs. 39% at five years, respectively; p = 0.56). Multivariate analysis for OS revealed that complex karyotype and t(8;14) were independent prognostic factors, but not CCH acquisition. Likewise, in the 56 Ph-positive ALL patients, CCH acquisition was not significantly associated with the CR rates (92% vs. 78%, respectively; p = 0.27), and the OS rates did not significantly differ between the two groups (34% vs. 40% at five years, respectively; p = 0.90). In multivariate analysis for OS, no independent prognostic factor was identified. Conclusion: Adult ALL patients with abnormal karyotype acquired CCH at diagnosis with a frequency comparable to that of AML patients. However, unlike AML patients, CCH acquisition was more frequently observed in younger population and did not show any prognostic impact in ALL patients. These findings suggested that biological backgrounds of CCH acquisition at diagnosis were possibly different between in patients with ALL and AML. So, to confirm these important findings, clinical studies with larger study subjects are warranted. DisclosuresHanda:Celgene: Honoraria, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau.

Prognostic significance of recurrent additional chromosomal abnormalities in adult patients with Philadelphia chromosome-positive acute lymphoblastic leukemia

In Philadelphia (Ph) chromosome-positive acute lymphoblastic leukemia (ALL), additional chromosomal abnormalities (ACAs) are frequently observed. We investigated the cytogenetic characteristics and prognostic significance of ACAs in Ph-positive ALL. We reviewed the clinical data and bone marrow cytogenetic findings of 122 adult Ph-positive ALL patients. The ACAs were examined for partial or whole chromosomal gains or losses, and structural aberrations. The overall survival (OS) and disease-free survival (DFS) of patients who received hematopoietic cell transplantation were compared between the isolated Ph group and ACA group. ACAs were present in 73.0% of all patients. The recurrent ACAs were extra Ph (24.7%), 9/9p loss (20.2%), and 7/7p loss (19.1%). Complex karyotype was found in 28.1% of patients in the ACA group. Younger patients (19-30 years) in the ACA group showed the highest frequency of extra Ph (54%) compared to other age groups. The OS in the ACA group was significantly shorter than in the isolated Ph group. The presence of an extra Ph chromosome or 9/9p loss was significantly associated with shorter OS and DFS, whereas 7/7p loss and complex karyotype were not associated with poorer prognosis. We suggest that subclassification of ACAs could be applied to prognostic investigation of Ph-positive ALL.

Correlation between deletion of the CDKN2 gene and tyrosine kinase inhibitor resistance in adult Philadelphia chromosome-positive acute lymphoblastic leukemia.

BackgroundFrequency relapses are common in Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukemia (ALL) following tyrosine kinase inhibitors (TKIs). CDKN2A/B is believed to contribute to this chemotherapy resistance.MethodsTo further investigate the association between CDKN2 status and TKI resistance, the prevalence of CDKN2 deletions and its correlation with a variety of clinical features was assessed in 135 Ph-positive ALL patients using interphase fluorescence in situ hybridization (I-FISH).ResultsResults showed that no difference occurred between patients with CDKN2 deletion (44/135) and wild-type patients in sex, age, and complete remission (CR) rate following induction chemotherapy combined with tyrosine kinase inhibitors (TKIs). However, CDKN2 deletion carriers demonstrated higher white blood cell (WBC) count, enhanced rates of hepatosplenomegaly (P = 0.006), and upregulation of CD20 expression (P = 0.001). Moreover, deletions of CDKN2 resulted in lower rates of complete molecular response (undetectable BCR/ABL), increased cumulative incidence of relapse, short overall survival (OS), and disease-free survival (DFS) time (P < 0.05) even though these patients received chemotherapy plus TKIs followed by allogenic hematopoietic stem cell transplantation (Allo-HSCT). In the case of 44 patients who presented with CDKN2 deletion, 18 patients were treated with dasatinib treatment, and another 26 patients were treated with imatinib therapy, and our study found that there were no differences associated with OS (P = 0.508) and DFS (P = 0.555) between the two groups.ConclusionsCDKN2 deletion is frequently acquired during Ph-positive ALL progression and serves as a poor prognostic marker of long-term outcome in Ph-positive ALL patients with CDKN2 deletion even after the second-generation tyrosine kinase inhibitor treatment.

Prognostic Impact of Cytogenetic Abnormalities in Adult Patients with Philadelphia-Chromosome (Ph)-Negative Acute Lymphoblastic Leukemia (ALL) Who Underwent Allogeneic Stem Cell Transplant (allo-SCT)

Background: Cytogenetic abnormalities at diagnosis are recognized as a potent prognostic factor for acute leukemia patients. Among acute myeloid leukemia patients, the prognostic implications of cytogenetic abnormalities have been established for those treated with chemotherapy as well as those undergoing allo-SCT. In the context of Ph-negative ALLpatients, cytogenetic abnormalities at diagnosis clearly stratify the prognosis, whereas it has not been elucidated whether similar prognostic stratification is applicable to allo-SCT recipients.Objective: The aim of this retrospective study was to assess the prognostic impact of cytogenetic abnormalities in adult Ph-negative ALL patients who underwent allo-SCT.Patients and Methods: The study cohort included 373 adult Ph-negative ALL patients aged over 15 years who underwent allo-SCT for the first time between January 2001 and December 2012 at the 23 institutions participating in the Kanto Study Group for Cell Therapy (KSGCT). Patients' clinical data were collected from the KSGCT database. The Institutional Review Board of Gunma University approved the protocol of this study. Karyotypes considered high risk (HR) included t(4;11), t(8;14), low hypodiploidy, and complex (equal or more than five abnormalities), and all other karyotypes were designated standard risk (SR). On this basis, 308 patients (82.6%) were categorized as SR and 65 patients (17.4%) were categorized as HR at diagnosis. Of the 373 patients, 267 underwent allo-SCT in complete remission (CR) (224 in the SR group and 43 in HR group), and 106 in non-CR (84 in the SR group and 22 in HR group). For analysis, the study population was stratified based on disease status at the time of transplant. Almost all patients were conditioned with total body irradiation (TBI)-containing myeloablative conditioning (MAC) regimens prior to transplantation. Overall survival (OS) was defined as the interval from the date of transplantation to the date of death. Non-relapse mortality (NRM) was defined as any death in continuous complete remission (CR). The Fisher's exact test was used for comparison of binary variables. OS and RFS were estimated by the Kaplan-Meier method, and compared using the log-rank test. Cumulative incidences (CI) of relapse and NRM were compared using the stratified Gray test. P < 0.05 was considered as statistically significant.Results:[Patients in CR] No significant difference in patient characteristics and transplant procedures was observed between the SR and HR groups. The 5-year OS rates were similar between the SR and HR groups (60.5% vs. 74.1%, respectively; p = 0.225) (Figure 1). Similarly, there were no significant differences in the 5-year CI of relapse and NRM rates between the two groups (relapse: 26.3% vs. 24.8%, respectively; p = 0.498, NRM: 19.6% vs. 10.0%, respectively; p = 0.232). Multivariate analysis for OS identified MAC and TBI-containing regimens, not cytogenetic risk, as significant positive prognostic factors.[Patients in non-CR] No significant difference was observed between the SR and HR groups in terms of patient characteristics or transplant procedures, although there was a female predominance in the HR group. Patients in the SR group had a significantly superior 5-year OS rate compared to the HR group (15.4% vs. 4.5%, respectively; p = 0.022). There was no significant difference in the 5-year CI of relapse between the SR and HR groups (60.3% vs. 50.0%, respectively; p = 0.411), whereas the 5-year CI of NRM in the SR group was significantly lower than that in the HR group (24.8% vs. 45.5%, respectively; p = 0.024). Multivariate analysis revealed cytogenetic risk group as an independent prognostic factor.Conclusion: These findings suggest that adult Ph-negative ALL patients in remission with HR cytogenetic abnormalities have similar transplant outcomes to those in the SR group. Considering the reported equality of the CR rates between the two groups, allo-SCT at an early clinical phase is recommended for HR group patients, reminiscent of Ph-positive ALL patients in the pre-imatinib era. Current transplant procedures do not improve outcomes for patients who are not in remission, especially those with HR cytogenetic abnormalities. DisclosuresUsuki:MSD: Other: personal fees, Research Funding; SymBio Pharmaceutical: Other: personal fees, Research Funding; GlaxoSmithKline: Other: personal fees, Research Funding; Shionogi: Other: personal fees; Fujimoto Pharmaceutical: Research Funding; Bristol-Myers Squibb: Other; Takeda Pharmaceutical: Research Funding; Nippon Shinyaku: Other: personal fees, Research Funding; Sanofi: Other: personal fees, Research Funding; Shire: Research Funding; Kyowa Hakko Kirin: Other: personal fees, Research Funding; Otsuka Pharmaceutical: Research Funding; Eisai: Research Funding; Novartis: Other: personal fees, Research Funding; Boehringer Ingelheim: Other: personal fees, Research Funding; Celgene: Other: personal fees, Research Funding; Sumitomo Dainippon Pharma: Other: personal fees, Research Funding; Chugai Pharmaceutical: Other: personal fees; Fuji Film RI Pharma: Other: personal fees; Taiho Pharmaceutical: Other: personal fees, Research Funding; Astellas: Research Funding. Nakaseko:Novartis: Honoraria, Research Funding, Speakers Bureau; BMS: Honoraria, Research Funding, Speakers Bureau; Pfizer: Honoraria, Research Funding, Speakers Bureau; Otsuka: Honoraria, Research Funding.

Newly diagnosed acute lymphoblastic leukemia in China (II): prognosis related to genetic abnormalities in a series of 1091 cases

The molecular characterization of cytogenetic abnormalities has not only provided insights into the mechanisms of leukemogenesis but also led to the establishment of new treatment strategies targeting these abnormalities and thereby further improve the prognosis of patients. We analyzed the prognosis of 1091 Chinese patients with newly diagnosed acute lymphoblastic leukemia (ALL) and explored the prognostic impacts of a large number of cytogenetic/molecular abnormalities. It was demonstrated that, in both B- and T-ALL settings, the prognosis was negatively correlated to the age as reported to date. For childhood T-ALL patients, it was also documented that the HOX11 expression represented a favorable prognostic factor as it was in adult ones. We identified CRLF2 overexpression as an intermediate-risk marker and Ik6 variant of IKZF1 gene as a high-risk one when stratifying pediatric B-ALL cases according to cytogenetic/molecular risks. We also found that Ik6 variant and CRLF2 overexpression had an important role in dictating the prognosis of Ph-negative patients, which may be useful markers in guiding the treatment of ALL in the future, with tyrosine kinase inhibitors on the other hand reversing the fate of Ph-positive ALL patients.

AMN107, Novel Aminopyrimidine Inhibitor of Bcr-Abl, Is Significantly More Potent Than Imatinib Mesylate Against Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia Cells.

Imatinib mesylate is effective against Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) but, when used as a single agent, responses are transient and most patients relapse within 4–6 months. AMN107 is a novel oral aminopyrimidine ATP-competitive inhibitor of the protein tyrosine kinase activity of Bcr-Abl. Following oral administration to animals, AMN107 is well absorbed, has a good pharmacokinetic profile, and is well tolerated. The activity of AMN107, relative to imatinib, in both Ph-positive (Z-119 and Z-181) and Ph-negative (Z-138) ALL cell lines was studied. Z-119 and Z-181 cells were derived from Ph-positive ALL patients and retained typical B-cell characteristics and phenotypes of the original leukemia, including cytogenetic abnormality t(9;22) and p190 Bcr/Abl kinase. Z-138, a Ph-negative cell line, was derived from a patient with chronic lymphocytic leukemia and supervening ALL. Treatment with AMN107 or imatinib for 3 days (MTS assay) inhibited proliferation of Z-119 cells with the IC50 values of 19.3 nM and 620.0 nM, respectively, revealing AMN107 to be 32 fold more potent than imatinib. Treatment of Z-181 cell line lasted for 4 days (MTS assay) because of lower growth rate of these cells: IC50 for AMN107 and imatinib were 1.6 nM and 63.9 nM, respectively, showing AMN107 to be 40 fold more potent than imatinib. Neither drug showed activity against Ph-negative Z-138 cells. We also compared the activity of AMN107 in Ph-positive ALL cell lines expressing p190 Bcr/Abl protein to that in Ph-positive chronic myeloid leukemia cell lines KBM5 and KBM7 expressing p210 Bcr/Abl protein. The activity was similar with IC50 in KBM5 cells of 11.3 nM and in KBM7 cells of 4.3 nM. In experiments focused on cell cycle analysis we found that at equipotent doses (as determined by MTS assay) both drugs induced cell accumulation in G0/G1 phase in Z-119 but not in Z-181. We demonstrated that increasing equipotent concentrations of AMN107 and imatinib induced activation of caspase-3 that resulted in apoptosis, as assessed by propidium iodide staining, in Z-119 cells, while Z-181 cells showed lack of apoptotic response. Following treatment with a broad range of AMN107 and imatinib doses for 3 hrs, Bcr/Abl expression and phosphorylation were determined in Z-119 cells by immunoprecipitation and Western blotting: Bcr/Abl phosphorylation was inhibited completely with AMN107 at 125.0 nM, and with imatinib at 2500 nM, confirming again the higher potency of AMN107. Finally, similar differential effect of AMN107 and imatinib on Bcr/Abl protein expression and phosphorylation was observed in leukemic cells obtained from blood of Ph-positive ALL patients. We conclude that AMN107 has significant activity against Ph-positive ALL cells and warrants investigation in patients with Ph-positive ALL.

Philadelphia chromosome-positive acute lymphoblastic leukemia in Taiwan.

From January 1986 to December 1998, 26 (23%) of 114 acute lymphoblastic leukemia (ALL) patients older than 15 years were found to have Philadelphia (Ph) chromosome. They accounted for 28% (26 of 94) of the patients with B-lineage ALL. Compared with the other 88 ALL patients, the leukemic cells from all but one Ph-positive ALL patients were early pre-B cells with a higher rate of CD34 expression (92% vs 50%, P<0.05). At presentation, the Ph-positive adult ALL patients had higher circulating blasts (mean 21.4 vs 3.66x10(4)/microl, P<0.05) and lower initial platelet counts (mean 4.47 vs 7.34x10(4)/microl, P<0.01) and showed a trend toward higher frequency of initial central nerve system (CNS) involvement (25% vs 11%, P=0.098) than the others. Among patients with adequate chemotherapy, 16 (64%) of the 25 Ph-positive ALL patients achieved complete remission (CR), an incidence marginally lower than that of Ph-negative ALL (62 of 76, 82%, P=0.06) and significantly lower than that of Ph-negative B-lineage ALL (50 of 58, 86%, P=0.0037). However, all patients relapsed except for those who received allogeneic hemopoietic stem cell transplantation (allo-HSCT). The probabilities of 5-year continuous CR and 5-year survival for Ph-positive adult ALL patients were significantly inferior to those for Ph-negative adult ALL patients (0% vs 12%, P=0.0001, and 7% vs 19%, P=0.047, respectively), and those for Ph-negative B-lineage ALL (0% vs 14%, P<0.0001, and 7% vs 23%, P=0.002, respectively). Prognostic factors were analyzed among the Ph-positive ALL patients including the 26 adults mentioned above and an additional 11 children. No clinical or biological characteristics such as age, sex, initial circulating blast count, extramedullary involvement, or CD34 expression had an impact on the disease outcome. Allo-HSCT in first CR may improve the probability of 5-year continuous CR (100% vs. 0% for those without allo-HSCT, P=0.0091) although only three patients received it in this study. In conclusion, Ph-positive ALL patients tended to have a poor prognosis, regardless of whether other possible risk factors were present or not. Aggressive treatment, such as high-dose chemotherapy with allo-HSCT, should be considered for these patients to improve survival.

Bcr Rearrangements in philadelphia chromosome-positive acute lymphoblastic leukemia: A study of five chinese patients in Taiwan

Cytogenetic studies were successfully conducted on 73 Chinese patients with acute lymphoblastic leukemia (ALL). A Philadelphia chromosome (Ph) was identified in four (9%) of the 46 children and in four (15%) of the 27 adults. None of these patients had any clinical features suggestive of chronic myelogenous leukemia (CML). Leukemic cells from five of the eight Ph-positive (Ph+) ALL patients were analyzed for bcr rearrangement by Southern blot analysis with three restriction enzymes and two bcr probes. One of the three children and both adult patients studied showed bcr rearrangement. Based on the data from the literature and the present study, 58% of adult and 14% cf childhood Ph+ ALL patients demonstrated bcr rearrangement. There were no significant differences in clinical or laboratory findings between the two groups of patients with or without bcr rearrangement. Patients who had Ph+ ALL but no bcr rearrangement appear to have been victims of de novo acute leukemia, but it was still difficult to determine whether patients with bcr rearrangement had acute lymphoid transformation of subclinical CML. More studies and longer follow-ups are needed for clarification.