Prognostic impact of pretreatment cytogenetics in adult Philadelphia chromosome-negative acute lymphoblastic leukemia in the era of minimal residual disease

A robust and validated integrated prognostic index for defining risk groups in adult acute lymphoblastic leukemia: an EWALL collaborative study

ABSTRACT

Risk stratification is crucial to the successful treatment of acute lymphoblastic leukemia (ALL). Although numerous risk factors have been identified, an optimal prognostic model for integrating variables has not been developed. We used individual patient data from 4 contemporary academic national clinical trials, UKALL14, NILG-ALL10/07, GIMEMA-LAL1913, and PETHEMA-ALL-HR2011, to generate and validate the European Working Group for Adult ALL prognostic index (EWALL-PI), which is based on white blood cell count, genetics, and end of induction minimal residual disease (MRD). Individual patient risk scores were calculated for 778 patients aged 15 to 67 years in complete remission using the validated UKALL-PI formula, applying minor modifications to reflect differences between pediatric and adult ALL. Per-trial analysis revealed that EWALL-PI correlated with relapse and death. Regression analysis revealed that each unit increase in EWALL-PI increased the risk of relapse or death by ∼30% with no evidence of heterogeneity across trials or patient subgroups. EWALL-PI-defined risk models outperformed the stratification algorithms used by each trial. Threshold analysis revealed an EWALL-PI threshold that divided patients with B cell and T cell into standard (EWALL-PI <2.50) and high (EWALL-PI ≥2.50) risk groups, respectively. Per-trial analysis showed that patients at high risk had a significantly increased relapse rate and inferior survival compared with patients with standard risk (subdistribution hazard ratio for relapse, ranged from 1.85 to 3.28; hazard ratio for death, 1.73 to 3.03). Subgroup analysis confirmed the robustness of these risk groups by sex, age, white blood cell count, and lineage. In conclusion, we validated an integrated risk model across 4 independent adult ALL clinical trials, demonstrating its utility defining clinically relevant risk groups.

Novel strategies to prevent and overcome relapse after allogeneic hematopoietic cell transplantation in acute lymphoblastic leukemia

The outcome of B-cell acute lymphoblastic leukemia (B-ALL) has improved over time with the incorporation of multi-agent chemotherapy in the treatment landscape as well as the recent approval of immunotherapeutic agents allowing a larger proportion of patients to undergo allogeneic hematopoietic cell transplantation (allo-HCT) which is still considered a potential curative approach. However, relapse post-transplant is still occurring and constitutes a common cause of treatment failure in B-ALL. The present review aims to discuss the novel strategies and therapies used to prevent and overcome relapse post allo-HCT in patients with ALL, focusing on the role of tyrosine kinase inhibitors in Philadelphia chromosome positive B-ALL, the role of innovative agents such as blinatumomab and inotuzumab ozogamicin, and finally the role of cellular therapy.

Results of salvage therapy with mini-hyper-CVD and inotuzumab ozogamicin with or without blinatumomab in pre-B acute lymphoblastic leukemia

BACKGROUND

Historically, adults with relapsed-refractory acute lymphoblastic leukemia (ALL) experienced poor outcomes with intensive chemotherapy. This mature analysis explores the benefit of the addition of sequential blinatumomab to low-intensity mini-Hyper-CVD chemotherapy with inotuzumab ozogamicin in this setting.

METHODS

Mini-Hyper-CVD (cyclophosphamide and dexamethasone at 50% dose reduction, no anthracycline, methotrexate at 75% dose reduction, cytarabine at 83% dose reduction) was combined with inotuzumab during the first 4 courses. From Patient #68 and onwards, inotuzumab was given in reduced and fractionated doses, and blinatumomab was added sequentially for 4 courses. Maintenance therapy with prednisone, vincristine, 6-mercaptopurine and methotrexate was given for 12 courses, and blinatumomab for 4 additional courses.

RESULTS

Among 110 patients (median age, 37 years) treated, 91 (83%) responded (complete response, 69 patients, 63%). Measurable residual disease negativity was documented in 75 patients (82% of responders). Fifty-three patients (48%) received allogeneic stem cell transplantation (SCT). Hepatic sinusoidal obstruction syndrome occurred in 9/67 patients (13%) on the original inotuzumab schedule and in 1/43 (2%) on the modified schedule. With a median follow-up of 48 months, the median overall survival (OS) was 17 months, and the 3 year OS was 40%. The 3 year OS was 34% with mini-Hyper-CVD plus inotuzumab and 52% with additional blinatumomab (P = 0.16). By landmark analysis at 4 months, the 3 year OS was 54%, similar between patients who did or did not receive allogeneic SCT.

CONCLUSION

Low-intensity mini-Hyper-CVD plus inotuzumab with or without blinatumomab showed efficacy in patients with relapsed-refractory ALL, with better survival after the addition of blinatumomab. Trial registration The trial was registered on clinicaltrials.gov with the identifier NCT01371630.

Expert Recommendations for the Diagnosis, Treatment, and Management of Adult B-Cell Acute Lymphoblastic Leukemia in Latin America

PURPOSE

Despite strong induction chemotherapy response rates, only 30%-40% of patients with adult B-cell acute lymphoblastic leukemia (ALL) attain long-term remission. This study analyzes ALL in Latin America (LA) and recommends diagnosis, treatment, and management protocols.

METHODS

The Americas Health Foundation organized a panel of hematologists from Argentina, Brazil, Chile, Colombia, and Mexico to examine ALL diagnosis and therapy and produce recommendations.

RESULTS

Lack of regional data, unequal access to diagnosis and therapy, inadequate treatment response, and uneven health care distribution complicate adult ALL management. The panel recommended diagnosis, first-line and refractory treatment, and post-transplantation maintenance. Targeted treatments, including rituximab, blinatumomab, and inotuzumab ozogamicin, are becoming available in LA and must be equitably accessed.

CONCLUSION

This review adapts global information on treating ALL to LA. Governments, the medical community, society, academia, industry, and patient advocates must work together to improve policies.

The evolution of acute lymphoblastic leukemia research and therapy at MD Anderson over four decades

Progress in the research and therapy of adult acute lymphoblastic leukemia (ALL) is accelerating. This analysis summarizes the data derived from the clinical trials conducted at MD Anderson between 1985 and 2022 across ALL subtypes. In Philadelphia chromosome-positive ALL, the addition of BCR::ABL1 tyrosine kinase inhibitors (TKIs) to intensive chemotherapy since 2000, improved outcomes. More recently, a chemotherapy-free regimen with blinatumomab and ponatinib resulted in a complete molecular remission rate of 85% and an estimated 3-year survival rate of 90%, potentially reducing the role of, and need for allogeneic stem cell transplantation (SCT) in remission. In younger patients with pre-B Philadelphia chromosome-negative ALL, the integration of blinatumomab and inotuzumab into the frontline therapy has improved the estimated 3-year survival rate to 85% across all risk categories. Our future strategy is to evaluate the early integration of both immunotherapy agents, inotuzumab and blinatumomab, with low-dose chemotherapy (dose-dense mini-Hyper-CVD-inotuzumab-blinatumomab) into the frontline setting followed by CAR T cells consolidation in high-risk patients, without any further maintenance therapy. In older patients, using less intensive chemotherapy (mini-Hyper-CVD) in combination with inotuzumab and blinatumomab has improved the 5-year survival rate to 50%. Among patients ≥ 65-70 years, the mortality in complete remission (CR) is still high and is multifactorial (old age, death in CR with infections, development of myelodysplastic syndrome or acute myeloid leukemia). A chemotherapy-free regimen with inotuzumab and blinatumomab is being investigated. The assessment of measurable residual disease (MRD) by next-generation sequencing (NGS) is superior to conventional assays, with early MRD negativity by NGS being associated with the best survival. We anticipate that the future therapy in B-ALL will involve less intensive and shorter chemotherapy regimens in combination with agents targeting CD19 (blinatumomab), CD20, and CD22 (inotuzumab). The optimal timing and use of CAR T cells therapy may be in the setting of minimal disease, and future trials will assess the role of CAR T cells as a consolidation among high-risk patients to replace allogeneic SCT. In summary, the management of ALL has witnessed significant progress during the past four decades. Novel combination regimens including newer-generation BCR::ABL1 TKIs and novel antibodies are questioning the need and duration of intensive chemotherapy and allogeneic SCT.

Comparison of the treatment results in adult patients with acute Ph-negative lymphoblastic leukemia on protocols of the Russian multicenter studies ALL-2009 and ALL-2016

Introduction. Over the past 5 years, signifi cant progress has been achieved in the treatment of patients with Ph-negative acute lymphoblastic leukemia (ALL). Treatment results were compared between two protocols of the Russian multicenter studies «ALL-2009» and «ALL-2016», in which multicomponent high-dose consolidation was not used. The principle of continuity of treatment was observed with modifi cation of doses of cytostatic drugs depending on the depth of cytopenia.

Aim – to compare the 5-year results of two studies and to determine the factors of unfavorable prognosis in the treatment of patients with ALL.

Materials and methods. The studies were performed from April 2009 to April 2016 (ALL-2009) and from April 2016 to September 2021 (ALL-2016), and 596 patients were included: 330 in ALL-2009 and 266 in ALL-2016. The analysis was performed in March 2022. The median age of patients in ALL-2009 was 28 years (15–55), in ALL-2016 – 32.5 years (18–55). Cytogenetic studies were performed in 242 patients in ALL-2009 (73.3 %) and 236 patients in ALL-2016 (88.7 %). Patients in the ALL-2016 protocol underwent a centralized assessment of minimal residual disease (MRD) by fl ow cytometry on protocol +70 day (after completion of two induction phases), +133 and +190 days. Transplantation of allogeneic stem hematopoietic cells was performed in 7 % of patients in ALL-2009 and in 9 % in ALL-2016.

Results. Overall, relapse-free survival (OS, RFS) and the probability of relapse for a period of 3 years from the moment of inclusion of patients in a particular study were 59 %, 63 % and 23 % for ALL-2009, and for ALL-2016 – 64 %, 59 % and 22 %, respectively. For patients with B-cell precursor ALL, two cytogenetic risk groups were formed, in which long-term survival rates differed signifi cantly: the standard group (hyperploid set of chromosomes and normal karyotype) – OS 63 %, RFS 70 %, and high cytogenetic risk (any abnormal karyotype, except for hyperploidy) – OS 49 %, RFS 52 % (р = 0.001, р = 0.0014). In T-ALL, cytogenetic markers had no prognostic value, but the immunophenotype of early T-cell precursor turned out to be an important predictor of poor prognosis (the probability of relapse was 52 % compared with 15 % for all other immunophenotypic variants). According to the results of centralized monitoring of MRD, it was determined that for B-cell precursor ALL, the signifi cant negative factors are the high cytogenetic risk group and positive MRD status at +70 day, and for T-cells, the early immunophenotype and positive MRD status at +133 day.

Treatment of Ph-Negative Acute Lymphoblastic Leukemia in Adolescents and Young Adults with an Affordable Outpatient Pediatric Regimen

BACKGROUND

B-cell acute lymphoblastic leukemia is frequent in Hispanic adolescents and young adults. Outcomes of implementation of pediatric-inspired regimens in low-and middle-income countries are not well known.

METHODS

In this study we treated 94 adolescents and young adults with a local BFM regimen designed to be affordable with the use of native L-asparaginase and mitoxantrone administered in an outpatient fashion, and the of BCR/ABL and measurable residual disease (MRD) determined by high sensitivity flow cytometry for risk stratification.

RESULTS

Induction mortality was 11%; 25% of patients had to abandon treatment or be transferred to another health system. Two-year overall (OS) and event free survival (EFS) were 61.5% and 49.8%, MRD-negative patients had a 24-month OS of 85.6% vs. 69.6% (p = .024) and EFS of 76% vs. 45.5% (p = .004). Patients older than 40 years and those who abandoned treatment had worse EFS. Overall drug costs in our regimen were 52% lower than those of CALGB10403.

CONCLUSION

The treatment of AYAs with ALL with an outpatient focus was implemented successfully at a reduced cost. Genetic risk assessment, treatment abandonment and lack of access to novel therapies remain major barriers for improving outcomes.

Diagnosis and treatment of acute lymphoblastic leukemia in Latin America

OBJECTIVE

to discuss the status and challenges associated with the management of acute lymphoblastic leukemia (ALL) in Latin America.

METHODS

This review summarizes various insights gained from information regarding diagnostic approaches and treatment strategies in adult patients with ALL in Latin American Countries.

RESULTS

Information regarding ALL in Latin America is scarce; however, many efforts have been made to overcomes these barriers. Nevertheless, major obstacles to successful treatment in Latin America and LMIC remain poor adherence, abandonment of treatment, and lack of supportive therapy and new therapeutic agents.

CONCLUSION

Further improvements in survival should be pursued by developing more Latin American registries, forming cooperative groups, developing educational models to facilitate earlier diagnosis and prevention of complications, better support therapy and management of infections, and adapting treatment strategies.

Therapeutic Advances in Immunotherapies for Hematological Malignancies

Following the success of immunotherapies such as chimeric antigen receptor transgenic T-cell (CAR-T) therapy, bispecific T-cell engager therapy, and immune checkpoint inhibitors in the treatment of hematologic malignancies, further studies are underway to improve the efficacy of these immunotherapies and to reduce the complications associated with their use in combination with other immune checkpoint inhibitors and conventional chemotherapy. Studies of novel therapeutic strategies such as bispecific (tandem or dual) CAR-T, bispecific killer cell engager, trispecific killer cell engager, and dual affinity retargeting therapies are also underway. Because of these studies and the discovery of novel immunotherapeutic target molecules, the use of immunotherapy for diseases initially thought to be less promising to treat with this treatment method, such as acute myeloid leukemia and T-cell hematologic tumors, has become a reality. Thus, in this coming era of new transplantation- and chemotherapy-free treatment strategies, it is imperative for both scientists and clinicians to understand the molecular immunity of hematologic malignancies. In this review, we focus on the remarkable development of immunotherapies that could change the prognosis of hematologic diseases. We also review the molecular mechanisms, development processes, clinical efficacies, and problems of new agents.

SOHO State of the Art Updates and Next Questions: Novel Transplant and Post-Transplant Options in Acute Lymphoblastic Leukemia

Allogeneic hematopoietic cell transplantation (alloHCT) is a potentially curative treatment approach for patients with high-risk acute lymphoblastic leukemia (ALL). Despite development of several novel therapies targeting B-cell ALL, alloHCT continues to play an essential role in management, but the identification of patients who are most likely to benefit from alloHCT in first or subsequent remissions continues to evolve. Broader donor options, including haploidentical donors and umbilical cord blood, have enabled alloHCT for more patients, but improvements in front-line therapy and increasing use of high-sensitivity measurable residual disease (MRD) quantification continue to modify the calculus for selecting which patients require transplantation. MRD quantification has become increasingly important as a prognostic indicator, as well as a trigger for therapeutic intervention, since the achievement of MRD negative complete remission is well-established to be associated with improved transplant outcomes. ALL remains the only malignancy with approved therapy for MRD positivity after achievement of remission, and use of Blinatumomab in this setting currently appears to be most effective when used as a bridge-to-transplant, rather than a destination or purely consolidative therapy. Expanding options for those with relapsed/refractory disease, including chimeric antigen receptor (CAR)-T cells, also render more patient in suitably deep remissions to enable alloHCT with a high likelihood of success. It remains unclear whether CAR-T cell therapies may obviate the need for alloHCT in some patients, and currently available data suggest there remains a role for alloHCT after CAR-T. Together, these therapeutic advances appear to be improving post-transplant outcomes. Nevertheless, more remains to be studied regarding how to optimize use of available and emerging cellular and immune modulating therapies to maximize the likelihood of long-term post-alloHCT remission in high-risk ALL.

Clinical Value of Measurable Residual Disease in Acute Lymphoblastic Leukemia

Measurable (minimal) residual disease (MRD) status in acute lymphoblastic leukemia (ALL) has largely superseded the importance of traditional risk factors for ALL, such as baseline white blood cell count, cytogenetics, and immunophenotype, and has emerged as the most powerful independent prognostic predictor. The development of sensitive MRD techniques, such as multicolor flow cytometry (MFC), quantitative polymerase chain reaction (PCR), and next-generation sequencing (NGS), may further improve risk stratification and expand its impact in therapy. Additionally, the availability of highly effective agents for MRD eradication, such as blinatumomab, inotuzumab ozogamicin, and chimeric antigen receptor (CAR) T-cell therapies, enabled the development of frontline regimens capable of eradicating MRD early in the treatment course. While long-term follow-up of this approach is lacking, it has the potential to significantly reduce the need for intensive post-remission treatments, including allogeneic bone marrow transplantation, in a significant proportion of patients with ALL.

Improved survival after allogeneic transplantation for acute lymphoblastic leukemia in adults: a Danish population-based study

We investigated trends of survival in a population-based cohort study of all 181 adults who received HCT for ALL in Denmark between 2000-2019. Patients had a median (min-max) age of 36 (18-74) years at HCT and were followed for a median of eight years. Overall survival (OS) improved over time with an estimated 2-year OS of 49% (CI 27-66%) in year 2000 versus 77% (CI 59-88%) in year 2019. More patients achieved cure over time (OR for cure per year 1.07, CI 1.00-1.15), while the rate of death in non-cured patients remained stable (HR of excess mortality per year 0.99, CI 0.93-1.06). Relapse decreased over time (HR 0.92 per year, CI 0.87-0.98), whereas non-relapse mortality did not change notably (HR 0.98 per year, CI 0.93-1.04). In conclusion, survival after HCT in adults with ALL has improved over the past two decades, primarily due to more patients achieving cure.

Outcomes of Acute Lymphoblastic Leukemia with KMT2A (MLL) rearrangement - The MD Anderson Experience

ALL with KMT2A rearrangement is associated with a poor prognosis, irrespective of the gene partner involved.

All patients with KMT2A-rearranged ALL benefit from allogeneic HSCT in first remission.

Acute lymphoblastic leukemia (ALL) with t(4;11)(q21;q23)-KMT2A-AFF1 is associated with a poor prognosis. The impact of KMT2A rearrangements other than t(4;11) is uncertain, and the benefit of allogeneic stem cell transplantation (HSCT) is unclear. We reviewed adult patients with ALL treated at our institution from 1984 to 2019 and identified 50 out of 1102 (5%) with KMT2A rearrangement, including 42 (84%) with t(4;11)/KMT2A-AFF1 and 8 (16%) with other gene partners. The median age was 45 years (range, 18-78 years); median white blood cell count was 109.0 3 109/L (range, 0.5-1573.0). The complete remission (CR) rate was 88%, and the rate of measurable residual disease negativity by flow cytometry at CR was 41% (76% overall during follow-up). At the last follow-up, 14 patients were alive. The 5-year overall survival (OS) rate was 18% (95% confidence interval [CI], 9% to 35%), with no difference between t(4;11) and other KMT2A rearrangements (P 5 .87). In a 4-month landmark analysis, the 5-year OS rate was 32% (95% CI, 14% to 70%) in patients who underwent HSCT vs 11% (95% CI, 3-39) in others (P 5 .10). Our study confirms the poor prognosis of ALL with any KMT2A rearrangement and the role of HSCT in these patients.

Therapeutic implications of menin inhibition in acute leukemias

Menin inhibitors are novel targeted agents currently in clinical development for the treatment of genetically defined subsets of acute leukemia. Menin has a tumor suppressor function in endocrine glands. Germline mutations in the gene encoding menin cause the multiple endocrine neoplasia type 1 (MEN1) syndrome, a hereditary condition associated with tumors of the endocrine glands. However, menin is also critical for leukemogenesis in subsets driven by rearrangement of the Lysine Methyltransferase 2A (KMT2A) gene, previously known as mixed-lineage leukemia (MLL), which encodes an epigenetic modifier. These seemingly opposing functions of menin can be explained by its various roles in gene regulation. Therefore, leukemias with rearrangement of KMT2A are predicted to respond to menin inhibition with early clinical data validating this proof-of-concept. These leukemias affect infants, children and adults, and lead to adverse outcomes with current standard therapies. Recent studies have identified novel targets in acute leukemia that are susceptible to menin inhibition, such as mutated Nucleophosmin 1 (NPM1), the most common genetic alteration in adult acute myeloid leukemia (AML). In addition to these alterations, other leukemia subsets with similar transcriptional dependency could be targeted through menin inhibition. This led to rationally designed clinical studies, investigating small-molecule oral menin inhibitors in relapsed acute leukemias with promising early results. Herein, we discuss the physiologic and malignant biology of menin, the mechanisms of leukemia in these susceptible subsets, and future therapeutic strategies using these inhibitors in acute leukemia.

Molecular-based and antibody-based targeted pharmacological approaches in childhood acute lymphoblastic leukemia

Introduction: Despite the significant survival improvement in childhood acutelymphoblastic leukemia (ALL), 15-20% of patients continue to relapse; outcomes following relapse remain suboptimal and have room for further improvement. Advances in genomics have shed new insights on the biology of ALL, led to the discovery of novel genomically defined ALL subtypes, refined prognostic significance and revealed new therapeutic vulnerabilities.Areas covered: In this review, the authors provide an overview of the genomic landscape of childhood ALL and highlight recent advances in molecular-based and antibody-based pharmacological approaches in the treatment of childhood ALL, from emerging preclinical evidence to published results of completed clinical trials.Expert opinion: Molecularly targeted therapies and immunotherapies have expanded the horizons of ALL therapy and represent promising therapeutic avenues for high-risk and relapsed/refractory ALL. These novel therapies are now moving into frontline ALL therapy and may define new treatment paradigms that aim to further improve survival and reduce chemotherapy-related toxicities in the management of pediatric ALL.

Acute lymphoblastic leukemia: A population-based study of outcome in the United States based on the surveillance, epidemiology, and end results (SEER) database, 1980-2017

The treatment in acute lymphoblastic Leukemia (ALL) has evolved and improved dramatically over the past four decades. We assessed the outcome of ALL overall, and the two major subsets of Philadelphia chromosome (Ph)-positive and Ph-negative ALL by age, time periods, ethnicity, median household income, and geographic county area. A total of 12 788 patients diagnosed with ALL from 1980 to 2017 were included. We performed an analysis to better evaluate the outcome evolution in ALL according to time period and patient's demographic factors. The overall 5-year survival rates have improved significantly over time, from 51% before 1990 to 72% since 2010. The survival rates for children (age 0 to 14 years) and adolescents (age 15 to 19 years) have improved from 73% and 55% before 1990 to 93% and 74% since 2010, respectively. Similarly, the rates had improved from 33% to 59% for adults 20 to 29 years old, 24% to 59% for 30 to 39 years old, and 14% to 43% for 40 to 59 years old between the two time periods. The rates remained under 30% in older patients (60+ years). Since 2010, patients with Ph-negative ALL had 5-year survival rate of 73% and those with Ph-positive ALL 50%. African Americans, Hispanic ethnicity, and lower household income were associated with inferior survival. The outcome of patients with ALL showed continued improvement across all age groups in the US. The recent introduction of targeted therapies, together with optimized supportive care, will continue to improve outcomes, particularly in older patients.

Minimal residual disease level determined by flow cytometry provides reliable risk stratification in adults with T-cell acute lymphoblastic leukaemia

Minimal residual disease (MRD) is an important independent prognostic factor for relapse and survival in acute lymphoblastic leukaemia (ALL). Compared with adult B-cell ALL, reports of adult T-cell ALL (T-ALL) MRD have been scarce and mostly based on molecular methods. We evaluated the prognostic value of multiparameter flow cytometry (FCM)-based MRD at the end of induction (EOI-MRD). The present retrospective study included 94 adult patients with T-ALL. MRD was detected by six- to eight-colour FCM. Patients who were EOI-MRD positive had a higher cumulative incidence of relapse (CIR) (87·6% vs. 38·8%, P = 0·0020), and a lower relapse-free survival (RFS) (5·4% vs. 61·0%, P = 0·0005) and overall survival (OS) (32·7% vs. 69·7%, P < 0·0001) than those who were EOI-MRD negative. Moreover, for patients who received allogeneic haematopoietic stem cell transplantation (allo-HSCT) at their first remission, EOI-MRD positivity was predictive of post-transplant relapse (2-year CIR: 68·2% vs. 4·0%, P = 0·0003). Multivariate analysis showed that EOI-MRD was an independent prognostic factor for CIR [hazard ratio (HR) 2·139, P = 0·046], RFS (HR 2·125, P = 0·048) and OS (HR 2·987, P = 0·017). In conclusion, EOI-MRD based on FCM was an independent prognostic factor for relapse and survival in adult T-ALL. For patients who underwent HSCT, EOI-MRD could be used to identify patients with a high risk of relapse after allo-HSCT.

Long-term follow-up of salvage therapy using a combination of inotuzumab ozogamicin and mini-hyper-CVD with or without blinatumomab in relapsed/refractory Philadelphia chromosome-negative acute lymphoblastic leukemia

BACKGROUND

The outcome of patients with relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) is poor. The combination of inotuzumab with low-intensity mini-hyper-CVD (mini-hyper-CVD; cyclophosphamide and dexamethasone at 50% dose reduction, no anthracycline, methotrexate at 75% dose reduction, cytarabine at 0.5 g/m² × 4 doses) chemotherapy has shown encouraging results. The sequential addition of blinatumomab might improve outcome in patients with R/R ALL.

METHODS

We used lower intensity chemotherapy, mini-hyper-CVD (cyclophosphamide and dexamethasone at 50% dose reduction, no anthracycline, methotrexate at 75% dose reduction, cytarabine at 0.5 g/m² x 4 doses) compared to conventional hyper-CVAD.

RESULTS

Ninety-six patients with a median age of 37 years (range, 18-87 years) were treated. Overall, 77 patients (80%) responded, 55 (57%) of whom achieved complete response. The overall measurable residual disease negativity rate among responders was 83%. Forty-four (46%) patients underwent later allogeneic stem cell transplantation. Veno-occlusive disease of any grade occurred in 10 (10%) patients. The rates were 13% with the original schedule and 3% with the use of lower-dose inotuzumab and sequential blinatumomab. With a median follow-up of 36 months, the median overall survival (OS) was 13.4 months, with 3-year OS rates of 33%. The 3-year OS rate for patients with CD22 expression ≥70% and without adverse cytogenetics (KMT2A rearrangements, low hypodiploidy/near triploidy) was 55%.

CONCLUSION

The combination of inotuzumab and low-intensity mini-hyper-CVD chemotherapy with or without blinatumomab shows sustained efficacy in patients with R/R ALL.

Recent Advances in Managing Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is characterized by chromosomal translocations and somatic mutations that lead to leukemogenesis. The incorporation of pediatric-type regimens has improved survival in young adults, and the incorporation of tyrosine kinase inhibitors for patients with Philadelphia chromosome-positive disease has led to further improvements in outcomes. However, older patients often have poor-risk biology and reduced tolerance to chemotherapy, leading to lower remission rates and overall survival. Regardless of age, patients with relapsed or refractory ALL have extremely poor outcomes. The advent of next-generation sequencing has facilitated the revolution in understanding the genetics of ALL. New genetic risk stratification together with the ability to measure minimal residual disease, leukemic blasts left behind after cytotoxic chemotherapy, has led to better tools to guide postremission approaches-that is, consolidation chemotherapy or allogeneic stem cell transplantation. In this article, we discuss the evolving and complex genetic landscape of ALL and the emerging therapeutic options for patients with relapsed/refractory ALL and older patients with ALL.

Optimal approach to the treatment of young adults with acute lymphoblastic leukemia in 2020

Akin to the introduction of tyrosine kinase inhibitors to Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL), pediatric-based asparaginase-heavy approaches have revolutionized the treatment of young adults with the Philadelphia chromosome-negative subset the past decades. Once again, we are approaching a new era. An era of precision medicine with immunotherapy and other molecularly targeted treatments that offers unique opportunities to customize treatment intensity with or without hematopoietic stem cell transplantation, reduce the burden of toxicities, and combat persistent residual disease. Recently approved agents for refractory/relapsed B-cell precursor ALL include the chimeric antigen receptor-modified T-cells, the anti-CD22 monoclonal antibody-drug conjugate, inotuzumab ozogamicin, and the bispecific anti-CD19 T-cell engager, blinatumomab. These agents are expected to move widely into the frontline setting along with the proteasome inhibitors, bortezomib and carfilzomib, as well as tyrosine kinase inhibitors for Philadelphia-like rearrangements that are especially frequent among young adults. To this add the BH3 mimetics, venetoclax and navitoclax, which are being widely explored in refractory/relapsed as well as frontline settings for B- and T-cell ALL. The promising anti-CD38 monoclonal antibody, daratumumab, is entering the scene of refractory/relapsed T-ALL, whereas the old purine analogue, nelarabine, is being evaluated in a new upfront setting. This review focuses on 2 main questions: How do we optimize frontline as well as salvage ALL treatment of young adults in the 2020s? Not least, how do we address the current burden of serious toxicities unique to young adults?

Recent Advances in Adult Acute Lymphoblastic Leukemia

PURPOSE OF REVIEW

This article reviews the recent advances in the pathophysiology and management of acute lymphoblastic leukemia (ALL) in adults.

RECENT FINDINGS

Addition of rituximab to standard chemotherapy improves survival in the frontline treatment of B cell ALL, and measurable residual disease (MRD) is the most important prognostic factor. Tyrosine kinase inhibitors (TKI), particularly ponatinib, in combination with Hyper-CVAD significantly improve outcomes in Ph + ALL challenging the benefit of allogeneic stem cell transplant in first line for these patients. Blinatumomab, inotuzumab ozogamicin, and chimeric antigen receptor (CAR) T cells are better options than chemotherapy alone for the treatment of relapsed or refractory ALL. Combination of these agents with chemotherapy and their incorporation in the frontline setting show promises to improve cure rates of ALL. Development of monoclonal antibodies, CAR T, and potent TKI has improved the outcome of ALL. Advances in our understanding of ALL biology are expected to bring new therapeutic strategies in the upcoming years.

Monitoring MRD in ALL: Methodologies, technical aspects and optimal time points for measurement

The accurate determination of minimal or measurable residual disease (MRD) during the early months of therapy in acute lymphoblastic leukemia is well established as the most important independent prognostic biomarker, predicting response to combination chemotherapy. Stratification based on MRD maximizes treatment effectiveness while minimizing adverse effects. Allele-specific real-time quantitative PCR of clone-defining immunoglobin/T-cell receptor gene rearrangements in the patients' leukemic clones and/or multiparametric flow cytometric tracking of leukemia-associated immunophenotypes are considered standard of care. Following recent advances in high throughput sequencing (HTS; next generation sequencing), much attention has been devoted to the development of HTS-based MRD assays, which can increase sensitivity; theoretically only limited by the number of cells input into the assay. Knowledge of the methods and limitations of each technology, along with awareness of the sensitivity and specificity of MRD at particular treatment time points is important in interpretation of the MRD value. MRD negativity at pre-established protocol-appropriate time points guides continuance with consolidation/maintenance chemotherapy, whereas positivity leads to a change to a biological therapy such as blinatumomab and intensification of therapy to allogeneic stem cell transplant. Positivity after maintenance may herald impending relapse enabling treatment intervention. MRD has been integral to the introduction of novel agents and cellular therapies into clinical trials and standard of care, but the long-term predictive value of MRD on outcome of novel therapies is not yet established. Integration of somatic genetics with MRD may further improve accurate identification of patients with the lowest and highest risk of relapse.

Monosomal karyotype is associated with poor outcomes in patients with Philadelphia chromosome-negative acute lymphoblastic leukemia receiving chemotherapy but not allogeneic hematopoietic stem cell transplantation

Monosomal karyotype (MK) is associated with poor prognosis in patients with myeloid neoplasms; however, its prognostic significance in Philadelphia chromosome-negative (Ph-negative) acute lymphoblastic leukemia (ALL) remains unclear. Data of 323 patients with Ph-negative ALL treated at Peking University People's Hospital were retrospectively analyzed. MK was identified in 49 (14.8%) patients. The patients with MK had lower hemoglobin levels (P = 0.026), lower platelet count (P = 0.032), higher percentages of blasts in the peripheral blood at diagnosis (P = 0.008), and higher percentages of high-risk karyotypes (P < 0.001) compared with those without MK. The complete remission (CR) rate and the minimal residual disease negativity rate were not significantly different between patients with and without MK. In the multivariate analysis, MK was identified as an independent factor associated with higher cumulative incidence of relapse (CIR) (hazard ratio (HR), 2.07; 95% confidence interval (CI), 1.02, 4.21; P = 0.043), shorter disease-free survival (DFS) (HR, 2.80; 95% CI, 1.20, 6.54; P = 0.017) and shorter overall survival (OS) (HR, 5.75; 95% CI, 2.07, 16.03; P = 0.001) in the chemotherapy cohort; however, MK had no impact on outcomes in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) cohort. Mantel-Byar analysis showed that allo-HSCT was associated with lower CIR (P < 0.001), longer DFS (P < 0.001), and longer OS (P < 0.001) in CR patients with MK. In conclusion, our study showed that MK was an independent predictor of poor outcomes in patients with Ph-negative ALL receiving chemotherapy but not allo-HSCT, and allo-HSCT could improve the outcomes of patients with MK.

Evolving therapy of adult acute lymphoblastic leukemia: state-of-the-art treatment and future directions

Recent years have witnessed major advances that have improved outcome of adults with acute lymphoblastic leukemia (ALL). The emergence of the concept of measurable residual disease has fine-tuned our prognostic models and guided our treatment decisions. The treatment paradigms of ALL have been revolutionized with the advent of tyrosine kinase inhibitors targeting BCR-ABL1, monoclonal antibodies targeting CD20 (rituximab), antibody-drug conjugates targeting CD22 (inotuzumab ozogamicin), bispecific antibodies (blinatumomab), and CD19 chimeric antigen receptor T cell therapy (tisagenlecleucel). These highly effective new agents are allowing for novel approaches that reduce reliance on intensive cytotoxic chemotherapy and hematopoietic stem cell transplantation in first remission. This comprehensive review will focus on the recent advances and future directions in novel therapeutic strategies in adult ALL.

Evaluation and management of measurable residual disease in acute lymphoblastic leukemia

With standard chemotherapy regimens for adults with acute lymphoblastic leukemia, approximately 90% of patients achieve complete remission. However, up to half of patients have persistent minimal/measurable residual disease (MRD) not recognized by routine microscopy, which constitutes the leading determinant of relapse. Many studies in pediatric and adult populations have demonstrated that achievement of MRD negativity after induction chemotherapy or during consolidation is associated with significantly better long-term outcomes, and MRD status constitutes an independently prognostic marker, often superseding other conventional risk factors. Persistence of MRD after intensive chemotherapy is indicative of treatment refractoriness and warrants alternative therapeutic approaches including allogeneic stem cell transplantation, blinatumomab, or investigational therapies such as inotuzumab ozogamicin or chimeric antigen receptor T cells. Furthermore, the incorporation of novel monoclonal antibodies or potent BCR-ABL1 tyrosine kinase inhibitors, such as ponatinib into frontline treatment may have the advantage of achieving higher rates of MRD negativity while minimizing chemotherapy-related toxicities. Many studies are therefore ongoing to determine whether this strategy can improve cure rates without the need for allogeneic stem cell transplantation.

The early achievement of measurable residual disease negativity in the treatment of adults with Philadelphia-negative B-cell acute lymphoblastic leukemia is a strong predictor for survival

The minimal or measurable residual disease (MRD) status following induction/consolidation chemotherapy is an important prognostic endpoint in adult patients with newly diagnosed acute lymphoblastic leukemia (ALL). However, the optimal time-point (TP) of MRD assessment and its impact on outcome remains unclear. We analyzed 215 patients with newly diagnosed Philadelphia negative B-cell ALL who received intensive chemotherapy, and had available MRD assessment by multicolor flow cytometry at two separate TPs. The median time to first TP (1TP) and second TP (2TP) were 24 and 110 days, respectively. At 1TP, 148 patients (68%) were MRD negative and 67 (32%) were positive. Of the 148 patients with negative MRD at 1TP, 147 (99%) maintained it through 2TP. Patients who were MRD negative at both TPs, early MRD responders, had the 3-year event-free survival (EFS), and overall survival (OS) rates of 65% and 76%, respectively. Patients with improved MRD status from positive to negative, late MRD responders, had lower 3-year EFS and OS rates, 42% and 58%, respectively (P = .001). Multivariate analysis showed that KMT2A (MLL) rearrangement and MRD positivity at 1TP were the only factors correlated with worse OS. In conclusion, the earlier achievement of MRD negative remission is a stronger prognostic factor for survival.

Impact of cytogenetic abnormalities on outcomes of adult Philadelphia-negative acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation: a study by the Acute Leukemia Working Committee of the Center for International Blood and Marrow Transplant Research

Cytogenetic risk stratification at diagnosis has long been one of the most useful tools to assess prognosis in acute lymphoblastic leukemia (ALL). To examine the prognostic impact of cytogenetic abnormalities on outcomes after allogeneic hematopoietic cell transplantation, we studied 1731 adults with Philadelphia-negative ALL in complete remission who underwent myeloablative or reduced intensity/non-myeloablative conditioning transplant from unrelated or matched sibling donors reported to the Center for International Blood and Marrow Transplant Research. A total of 632 patients had abnormal conventional metaphase cytogenetics. The leukemia-free survival and overall survival rates at 5 years after transplantation in patients with abnormal cytogenetics were 40% and 42%, respectively, which were similar to those in patients with a normal karyotype. Of the previously established cytogenetic risk classifications, modified Medical Research Council-Eastern Cooperative Oncology Group score was the only independent prognosticator of leukemia-free survival (P=0.03). In the multivariable analysis, monosomy 7 predicted post-transplant relapse [hazard ratio (HR)=2.11; 95% confidence interval (95% CI): 1.04-4.27] and treatment failure (HR=1.97; 95% CI: 1.20-3.24). Complex karyotype was prognostic for relapse (HR=1.69; 95% CI: 1.06-2.69), whereas t(8;14) predicted treatment failure (HR=2.85; 95% CI: 1.35-6.02) and overall mortality (HR=3.03; 95% CI: 1.44-6.41). This large study suggested a novel transplant-specific cytogenetic scheme with adverse [monosomy 7, complex karyotype, del(7q), t(8;14), t(11;19), del(11q), tetraploidy/near triploidy], intermediate (normal karyotype and all other abnormalities), and favorable (high hyperdiploidy) risks to prognosticate leukemia-free survival (P=0.02). Although some previously established high-risk Philadelphia-negative cytogenetic abnormalities in ALL can be overcome by transplantation, monosomy 7, complex karyotype, and t(8;14) continue to pose significant risks and yield inferior outcomes.

Rationale for targeting BCL6 in MLL-rearranged acute lymphoblastic leukemia

Chromosomal rearrangements of the mixed lineage leukemia (MLL) gene occur in ∼10% of B-cell acute lymphoblastic leukemia (B-ALL) and define a group of patients with dismal outcomes. Immunohistochemical staining of bone marrow biopsies from most of these patients revealed aberrant expression of BCL6, a transcription factor that promotes oncogenic B-cell transformation and drug resistance in B-ALL. Our genetic and ChIP-seq (chromatin immunoprecipitation [ChIP] combined with high-throughput sequencing) analyses showed that MLL-AF4 and MLL-ENL fusions directly bound to the BCL6 promoter and up-regulated BCL6 expression. While oncogenic MLL fusions strongly induced aberrant BCL6 expression in B-ALL cells, germline MLL was required to up-regulate Bcl6 in response to physiological stimuli during normal B-cell development. Inducible expression of Bcl6 increased MLL mRNA levels, which was reversed by genetic deletion and pharmacological inhibition of Bcl6, suggesting a positive feedback loop between MLL and BCL6. Highlighting the central role of BCL6 in MLL-rearranged B-ALL, conditional deletion and pharmacological inhibition of BCL6 compromised leukemogenesis in transplant recipient mice and restored sensitivity to vincristine chemotherapy in MLL-rearranged B-ALL patient samples. Oncogenic MLL fusions strongly induced transcriptional activation of the proapoptotic BH3-only molecule BIM, while BCL6 was required to curb MLL-induced expression of BIM. Notably, peptide (RI-BPI) and small molecule (FX1) BCL6 inhibitors derepressed BIM and synergized with the BH3-mimetic ABT-199 in eradicating MLL-rearranged B-ALL cells. These findings uncover MLL-dependent transcriptional activation of BCL6 as a previously unrecognized requirement of malignant transformation by oncogenic MLL fusions and identified BCL6 as a novel target for the treatment of MLL-rearranged B-ALL.

Establishment and characterization of a novel childhood acute lymphoblastic leukemia cell line, HXEX-ALL1, with chromosome 9p and 17p deletions

Background

Although contemporary chemotherapy has improved the cure rate of childhood acute lymphoblastic leukemia (ALL) to nearly 90%, relapsed/refractory ALL is still a leading cause of tumor-related death in children. To clarify the underlying mechanisms of relapsed/refractory childhood ALL, researchers urgently need to establish novel cell models from patients with relapsed ALL after treatment with contemporary chemotherapy.

Methods

Cell culture technique was used to establish the HXEX-ALL1 cell line from primary B cell precursor ALL (BCP-ALL) cells. Molecular and cellular biological techniques including flow cytometry, polymerase chain reaction (PCR), short tandem repeat (STR) analysis, conventional cytogenetics, and chromosomal microarray analysis (CMA) were used to characterize the HXEX-ALL1 cell line. Nude mice were used for xenograft studies.

Results

A stable ALL cell line, HXEX-ALL1, derived from a 6-year-old boy of Han nationality with BCP-ALL at the second relapse, was established and maintained in culture for more than 18 months. The HXEX-ALL1 cell line was authenticated as being derived from primary leukemia cells based on morphologic, immunophenotypic, cytogenetic and STR analyses and demonstrated tumorigenicity in nude mice. WGS data showed that there were 27,006 novel single nucleotide polymorphisms (SNPs) and 193,951 novel insertion/deletions (InDels) in HXEX-ALL1 cells. Compared with the other BCP-ALL cell lines in use, the HXEX-ALL1 cells have a special karyotype represented by trisomy 8 and 9p and 17p deletions with a multidrug resistance phenotype, especially highly resistant to asparaginase.

Conclusions

The HXEX-ALL1 cell line may prove to be a useful model for the study of relapsed/refractory childhood ALL, particularly for the researches on asparaginase resistance.

Prognostic implications of cytogenetics in adults with acute lymphoblastic leukemia treated with inotuzumab ozogamicin

Karyotype is frequently used to predict response and outcome in leukemia. This post hoc exploratory analysis evaluated the relationship between baseline cytogenetics and outcome in patients with relapsed/refractory acute lymphoblastic leukemia (R/R ALL) treated with inotuzumab ozogamicin (InO), a humanized CD22 antibody conjugated to calicheamicin, in the phase 3, open-label, randomized INO-VATE trial. Data as of March 8, 2016, are presented in this analysis. Of the 326 patients randomized, 284 had screening karyotyping data (144 in the InO arm and 140 in the standard care [SC] arm). With InO, complete remission or complete remission with incomplete hematologic recovery (CR/CRi), minimal residual disease negativity rates, and overall survival (OS) were not significantly different between cytogenetic subgroups. CR/CRi rates favored InO over SC in the diploid with ≥20 metaphases, complex, and "other" cytogenetic subgroups. The OS hazard ratio favored InO over SC in the diploid with ≥20 metaphases, complex, and other cytogenetic subgroups. Generally, InO is effective and provides substantial clinical benefit in patients with R/R ALL who have specific baseline karyotypes.

The poor prognosis of low hypodiploidy in adults with B-cell precursor acute lymphoblastic leukaemia is restricted to older adults and elderly patients

The prognostic significance of low-hypodiploidy has not been extensively evaluated in minimal residual disease (MRD)-oriented protocols for adult acute lymphoblastic leukaemia (ALL). We analysed the outcome of hypodiploid adult ALL patients treated within Programa Español de Tratamientos en Hematología (PETHEMA) protocols. The 5-year cumulative incidence of relapse (CIR) of low-hypodiploid B-cell precursor (BCP)-ALL was significantly higher than that of high-hypodiploids (52% vs. 12%, P = 0.013). Low-hypodiploid BCP-ALL patients aged ≤35 years showed superior survival (71% vs. 21%, P = 0.026) and lower 5-year CIR (17% vs. 66%, P = 0.090) than low-hypodiploids aged >35 years. Older adults and elderly low-hypodiploid BCP-ALL patients show dismal prognosis although achieving an end-induction good MRD response.

Recommendations for the assessment and management of measurable residual disease in adults with acute lymphoblastic leukemia: A consensus of North American experts

Measurable residual disease (MRD) that persists after initial therapy is a powerful predictor of relapse and survival in acute lymphoblastic leukemia (ALL). However, the optimal use of this information to influence therapeutic decisions is controversial. Herein, we comprehensively review the role of MRD assessment in adults with ALL, including methods to quantify residual leukemia cells during remission, prognostic impact of MRD across ALL subtypes, and available therapeutic approaches to eradicate MRD. This review presents consensus statements and provides an evidence-based framework for practicing hematologists and oncologists to use MRD information to make rational treatment decisions in adult patients with ALL.

Hematopoietic Stem Cell Transplantation in the Era of Engineered Cell Therapy

PURPOSE OF REVIEW

Cellular therapy using T cells modified to express chimeric antigen receptors (CAR-T cells) has had striking success in patients that have failed previous treatment for CD19+ B cell non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL), or acute lymphoblastic leukemia (ALL). Curative therapy for this group of diseases has previously been limited to allogeneic hematopoietic cell transplantation HCT (alloHCT). The recent results of CAR-T cell therapy raise the question of how best to integrate CAR-T cell therapy and alloHCT in the care of these patients.

RECENT FINDINGS

Within the past 2 years, results from larger trials and increased follow-up of patients treated with CD19 CAR-T cell therapy suggest that some may achieve durable remission without transplant. The balance of efficacy and toxicity for CAR-T cell therapy and alloHCT vary by disease type, disease status at the time of treatment, patient characteristics, and the specific therapy employed. There are early signals that subsequent transplantation of patients who have achieved remission with CAR-T may be a potentially viable (though expensive) strategy.

Trisomy 5 as the sole chromosomal anomaly in acute lymphoblastic leukaemia

Trisomy 5 as the sole cytogenetic aberration in acute lymphoblastic leukaemia (ALL) is exceedingly rare. As such, its prognostic and therapeutic relevance remains unknown. We report a case of an 18-year-old young man who was diagnosed with B cell ALL with trisomy 5 as the sole chromosomal abnormality. He was treated with chemotherapy and went into complete remission. On the 14th month of treatment, he relapsed with central nervous system involvement characterised by leukaemic infiltration of the optic nerve and facial palsy. He subsequently underwent reinduction chemotherapy with aggressive intrathecal chemotherapy followed by posterior globe and whole brain radiation therapy. He is currently on his 26th month of treatment, in second remission, with complete resolution of leukaemic infiltrative optic neuropathy and facial paralysis. As more cases of this nature are reported, we will be able to determine the relevance of this distinct cytogenetic entity.

Additional Cytogenetic Abnormalities with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia on Allogeneic Stem Cell Transplantation in the Tyrosine Kinase Inhibitor Era

Cytogenetic abnormalities are well known and powerful independent prognostic factors for various hematologic disorders. Although the combination of chemotherapy with tyrosine kinase inhibitor (TKI) is now considered the standard of care in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia, little is known about the impact of additional cytogenetic abnormalities (ACAs). Therefore, we retrospectively evaluated 1375 adult patients who underwent their first allogeneic hematopoietic stem cell transplantation in the TKI era. In this study, 224 patients had ACAs (16.3%). The ACAs that were seen in more than 20 cases (1.5%) were as follows: -7, der(22), der(9), +8, and +X. Overall survival at 4 years was 56.9% (95% confidence interval [CI], 49.4% to 63.7%) in the group with ACAs and 60.5% (95% CI, 57.3% to 63.5%) in the group without ACAs (P = .266). The cumulative incidence of relapse at 4 years was 28.9% (95% CI, 22.6% to 35.6%) in the group with ACAs and 21.9% (95% CI, 19.4% to 24.6%) in the group with Ph alone (P = .051). In multivariate analyses there were no statistically significant differences in the risk of overall mortality or risk of relapse between the groups with and without ACAs. In the subgroup analyses of specific ACAs, although the presence of +8 was associated with a higher relapse rate in univariate and multivariate analyses, no specific ACA was associated with poor overall survival. Further studies will be needed to verify the impact of specific ACAs on transplantation outcomes.

Novel Therapies for Older Adults With Acute Lymphoblastic Leukemia

PURPOSE OF REVIEW

Older adults with acute lymphoblastic leukemia (ALL) have worse survival compared to their younger counterparts. Here, we review the reasons for the poorer outcomes of older patients with ALL and also summarize the current and future therapeutic approaches to ALL in the elderly population.

RECENT FINDINGS

The poor outcomes of older adults with ALL are driven largely by lack of tolerance to standard-dose chemotherapy, which leads to unacceptably high rates of myelosuppression-related deaths. Recent studies have shown promising results with the use of low-intensity or chemotherapy-free regimens in older patients with ALL, which are able to retain efficacy without excess toxicity. Novel antibody constructs such as inotuzumab ozogamicin and blinatumomab as well as potent later-generation tyrosine kinase inhibitors such as ponatinib hold significant promise in the management of ALL in the older adult. Innovative combination strategies may further improve the outcomes of these patients.

DNA methylation holds prognostic information in relapsed precursor B-cell acute lymphoblastic leukemia

Background

Few biological markers are associated with survival after relapse of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In pediatric T-cell ALL, we have identified promoter-associated methylation alterations that correlate with prognosis. Here, the prognostic relevance of CpG island methylation phenotype (CIMP) classification was investigated in pediatric BCP-ALL patients.

Methods

Six hundred and one BCP-ALL samples from Nordic pediatric patients (age 1–18) were CIMP classified at initial diagnosis and analyzed in relation to clinical data.

Results

Among the 137 patients that later relapsed, patients with a CIMP− profile (n = 42) at initial diagnosis had an inferior overall survival (pOS_5years 33%) compared to CIMP+ patients (n = 95, pOS_5years 65%) (p = 0.001), which remained significant in a Cox proportional hazards model including previously defined risk factors.

Conclusion

CIMP classification is a strong candidate for improved risk stratification of relapsed BCP-ALL.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0466-3) contains supplementary material, which is available to authorized users.

Current challenges and opportunities in treating adult patients with Philadelphia-negative acute lymphoblastic leukaemia

Significant advances have been made in recent years in the field of Philadelphia-negative acute lymphoblastic leukaemia (ALL). New insights into the biology and genetics of ALL as well as novel clinical observations and new drugs are changing the way we diagnose, risk-stratify and treat adult patients with ALL. New genetic subtypes and alterations refine risk stratification and uncover new actionable therapeutic targets. The incorporation of more intensive, paediatric and paediatric-inspired approaches for young adults seem to have a positive impact on survival in this population. Minimal residual disease at different time points can assist in tailoring risk-adapted interventions for patients based on individual response. Finally, novel targeted approaches with monoclonal antibodies, immunotherapies and small molecules are moving through clinical development and entering the clinic. The aim of this review is to consolidate the abundance of emerging data and to review and revisit the concepts of risk-stratification, choice of induction and post-remission strategies as well as to discuss and update the approach to specific populations with ALL, such as young adult, elderly/unfit and relapsed/refractory patients with ALL.

Impact of cytogenetic abnormalities in adults with Ph-negative B-cell precursor acute lymphoblastic leukemia

Multiple cytogenetic subgroups have been described in adult Philadelphia chromosome (Ph)-negative B-cell precursor (BCP) acute lymphoblastic leukemia (ALL), often comprising small numbers of patients. In this study, we aimed to reassess the prognostic value of cytogenetic abnormalities in a large series of 617 adult patients with Ph-negative BCP-ALL (median age, 38 years), treated in the intensified Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/2005 trials. Combined data from karyotype, DNA index, fluorescence in situ hybridization, and polymerase chain reaction screening for relevant abnormalities were centrally reviewed and were informative in 542 cases (88%), allowing classification in 10 exclusive primary cytogenetic subgroups and in secondary subgroups, including complex and monosomal karyotypes. Prognostic analyses focused on cumulative incidence of failure (including primary refractoriness and relapse), event-free survival, and overall survival. Only 2 subgroups, namely t(4;11)/KMT2A-AFF1 and 14q32/IGH translocations, displayed a significantly worse outcome in this context, still observed after adjustment for age and after censoring patients who received allogeneic stem cell transplantation (SCT) in first remission at SCT time. A worse outcome was also observed in patients with low hypodiploidy/near triploidy, but this was likely related to their higher age and worse tolerance to therapy. The other cytogenetic abnormalities, including complex and monosomal karyotypes, had no prognostic value in these intensive protocols designed for adult patients up to the age of 60 years.

TP53 mutation does not confer a poor outcome in adult patients with acute lymphoblastic leukemia who are treated with frontline hyper-CVAD-based regimens

BACKGROUND

Tumor protein 53 (TP53) mutations are uncommon in adult patients with acute lymphoblastic leukemia (ALL) and predict a poor outcome.

METHODS

TP53 mutation analysis was performed in 164 newly diagnosed adult patients with ALL using a combination of targeted amplicon-based next-generation sequencing and Sanger sequencing.

RESULTS

TP53 mutations were detected in 25 patients (15%), with a median allelic frequency of 42.2% (range, 5.6%-93.8%). The majority of mutations were single-nucleotide variants of missense type and involved the DNA-binding domain. TP53-mutated (TP53^mut ) ALL was found to be significantly associated with older age, lower median white blood cell and platelet counts, lower frequency of Philadelphia chromosome and a higher frequency of low hypodiploid karyotype compared with ALL with wild-type TP53 (TP53^wt ). To evaluate the prognostic effect of TP53 mutations, the authors selected 146 patients with B-cell immunophenotype ALL (24 with TP53^mut and 122 with TP53^wt ) who were uniformly treated with frontline hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD)-based regimens; >90% of these individuals also received a monoclonal antibody. Over a median follow-up duration of 15 months, there was no significant difference in the median overall survival, event-free survival, and duration of complete remission noted between patients with TP53^mut ALL and those with TP53^wt ALL.

CONCLUSIONS

Hyper-CVAD-based regimens appear to negate the poor prognostic impact of TP53 mutations in patients with adult B-cell immunophenotype ALL. Cancer 2017;123:3717-24. © 2017 American Cancer Society.

Poor outcomes associated with +der(22)t(9;22) and -9/9p in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia receiving chemotherapy plus a tyrosine kinase inhibitor

In patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) treated with chemotherapy plus a tyrosine kinase inhibitor (TKI), the prognostic impact of additional chromosomal abnormalities (ACAs) is not well-established. We evaluated the prognostic impact of individual ACAs in 152 patients with Ph+ ALL receiving first-line intensive chemotherapy plus either imatinib (n = 36), dasatinib (n = 74), or ponatinib (n = 42). ACAs were identified in 118 patients (78%). Compared to outcomes of patients without ACAs, ACAs were not associated with differences in either relapse-free survival (RFS; P = 0.42) or overall survival (OS; P = 0.51). When individual ACAs were evaluated, +der(22)t(9;22) and/or -9/9p in the absence of high hyperdiploidy (HeH) was present in 16% of patients and constituted a poor-risk ACA group. Patients with one or more poor-risk ACAs in the absence of HeH had significantly shorter RFS (5-year RFS rate 33% versus 59%, P = 0.01) and OS (5-year OS rate 24% versus 63%, P = 0.003). Poor-risk ACAs were prognostic in patients who received imatinib and dasatinib but not in those who received ponatinib. By multivariate analysis, this poor-risk ACA group was independently associated with worse RFS (HR 2.03 [95% CI 1.08-3.30], P = 0.03) and OS (HR 2.02 [95% CI 1.10-3.71], P = 0.02). Patients with Ph+ ALL who have +der(22)t(9;22) and/or -9/9p in the absence of HeH have relatively poor outcomes when treated with chemotherapy plus a TKI.