BACKGROUND:Varnimcabtagene autoleucel (var-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy with adaptive intra-patient dose escalation and was approved in Spain in 2021 for patients older than 25 years with relapsed or refractory B-cell precursor acute lymphoblastic leukaemia. We report activity and safety from var-cel's pivotal trial in this patient population. METHODS:This multicentre, single-arm, phase 2 trial was conducted at nine academic centres in Spain. Eligible patients had CD19+ B-cell precursor acute lymphoblastic leukaemia in the first relapse or refractory disease, either ineligible for allogeneic haematopoietic cell transplantation (HCT) or with relapsed disease after allogeneic HCT; centralised measurable disease in peripheral blood or bone marrow, or both, using flow cytometry; were aged 18-70 years; and had an Eastern Cooperative Oncology Group performance status of 0-2. Patients received a single course of intravenous lymphodepleting chemotherapy with fludarabine (30 mg/m2 per day for 3 days) plus cyclophosphamide (300 mg/m2 per day for 3 days), followed by intravenous fractionated var-cel escalation (0·1, 0·3, 0·6, and 2·0 × 106 CAR T cells per kg) separated by at least 24 h, with each fraction contingent on safety criteria. The primary endpoint was complete response with undetected measurable residual disease (MRD; sensitivity of ≤10-5) determined by flow cytometry by day 28 from var-cel administration, assessed in the efficacy population (defined as all patients who received at least one var-cel fraction). Safety was analysed in patients that initiated lymphodepletion. This study is registered with ClinicalTrials.gov, NCT04778579 (completed). FINDINGS:Between May 19, 2021, and July 6, 2023, 50 patients were assessed for eligibility, 12 were ineligible, and 38 were enrolled. 37 (97%) of 38 underwent leukapheresis (ITT population), 33 (87%) initiated lymphodepleting chemotherapy (safety population), and 32 (84%) received at least one var-cel fraction (efficacy population). Five patients who underwent leukapheresis did not receive var-cel due to rapid disease progression (n=3), death due to veno-oclusive disease (n=1), and persistent COVID-19 (n=1). Patients receiving var-cel had a median age of 40 years (33-48); of whom, 16 (50%) were female and 16 (50%) were male. By data cutoff (Jan 18, 2024), the median follow-up from infusion was 8·6 months (IQR 5·1-14·4) and 27 (84·4% [95% CI 67·2-94·7]) of 32 patients who received at least one dose of var-cel had a complete response with undetected MRD by day 28. Treatment-emergent adverse events occurred in 31 (94%) of 33 patients. The most common grade 3 or higher adverse events were neutropenia in 15 (45%) patients, thrombocytopenia in seven (21%), anaemia in five (15%), and cytokine release syndrome in four (12%). Immune effector cell-associated neurotoxicity syndrome and cerebral oedema was observed in one patient (3%; grade ≥3), and immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome occurred in two (6%; one resulted in death after protocol violation due to infusion during uncontrolled sepsis). INTERPRETATION:Var-cel induced deep remissions with low incidence of severe cytokine release syndrome and any-grade immune effector cell-associated neurotoxicity syndrome, supporting fractionated dose escalation as a strategy that preserves activity, limits acute toxic effects, and supports a hospital-based approach that could expand access to CAR T-cell therapy. FUNDING:Instituto de Salud Carlos III Subdirección General de Evaluación y Fomento de la Investigación Sanitaria and Fondo Europeo de Desarrollo Regional, CaixaResearch, Servei Català de la Salut, Servicio Madrileño de Salud, Servicio Murciano de Salud, Salud de Castilla y León, Servicio Andaluz de Salud, and Servicio Navarro de Salud-Osasunbidea. TRANSLATION:For the Spanish translation of the abstract see Supplementary Materials section.

The treatment of adults with Philadelphia chromosome-positive ALL (Ph+ ALL) has evolved significantly over the past 25 years. These changes have been driven largely by the development of potent BCR::ABL1 tyrosine kinase inhibitors (TKIs) such as ponatinib, more accurate risk stratification and monitoring of measurable residual disease (MRD) and, most recently, the frontline use of blinatumomab-based, chemotherapy-free regimens. Although the historical standard of care for newly diagnosed Ph+ ALL was intensive chemotherapy followed by allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in first remission, now most patients can achieve deep and durable remissions-and even cure-with a chemotherapy-free regimen, without the routine need for allo-HSCT. Although the role of allo-HSCT in first remission is diminishing in this new treatment landscape, allo-HSCT remains a reasonable consolidative option for patients with high-risk clinical or molecular features or in treatment settings where frontline blinatumomab and/or high-sensitivity MRD monitoring are not routinely available. With optimal frontline therapy and close disease monitoring, relapses of Ph+ ALL are increasingly uncommon but still pose a significant clinical challenge. Several new agents, including novel TKIs, bispecific antibodies, and chimeric antigen receptor T-cell therapies, are being evaluated in the relapsed/refractory setting and may eventually also play a role in frontline treatment of this disease.

ABSTRACT:In adults with Philadelphia chromosome-negative (Ph-) acute lymphoblastic leukemia (ALL) genetic risk is usually combined with measurable residual disease (MRD) assignment to consolidation therapy. However, this combination is not uniform across trials and centralized assessment is not always performed. This study analyzed patient outcomes using centrally assessed MRD and genetics. Patients with high genetic risk (HGR), those who required 2 induction cycles for complete remission (CR), and patients with CR with end-of-induction (EOI) MRD of ≥0.01% were assigned to allogeneic hematopoietic stem cell transplant (allo-HSCT), whereas the remaining patients were assigned to delayed consolidation and maintenance. HGR for B-cell ALL included KMT2A rearrangements, low hypodiploidy and age of >35 years, homozygous TP53 mutations/deletions, or concomitant IKZF1 and CDKN2A/B deletions. HGR in T-cell ALL (T-ALL) included absence of NOTCH1/FBXW7 mutations and/or K/NRAS or PTEN alterations. Patients with early T-cell precursor (ETP) ALL received a different induction regimen, and all were assigned to allo-HSCT. Median age of 436 patients was 39 years (range, 18-60), 332 with B-lineage ALL and 104 with T-ALL. By intention to treat, 243 patients without ETP ALL (61%) were assigned to allo-HSCT and 157 (39%) to chemotherapy. The 3-year overall survival (OS) probability was 64% (95% confidence interval [CI], 58-69). For patients with CR and EOI MRD of <0.01% without HGR (n = 109), the OS probability was 81% (95% CI, 70-89), compared with 50% (95% CI, 34-63) for MRD-negative patients with HGR (n = 64). In patients with ETP ALL, the probability of 3-year OS was 61% (95% CI, 37-79). The combination of genetics and MRD allows accurate identification of adult patients with Ph- ALL who are candidates for allo-HSCT or chemotherapy. This trial was registered at www.clinicaltrials.gov as NCT04179929.

Abstract Patients with relapsed/refractory T-cell acute lymphoblastic leukemia (R/R T-ALL) have very poor prognosis. CAR T-cell therapy is being explored in these patients with encouraging results. Specifically, CD1a-directed CAR T-cells are being explored in clinical trials to treat cortical T-ALL (CD1a+), but there are no data on outcome in this subgroup of patients before this therapy. This retrospective, observational study aimed to describe the characteristics and outcomes of patients with R/R CD1a + T-ALL. We included pediatric and adult patients diagnosed with R/R CD1a + T-ALL in 25 sites of Spain between March 2006 and May 2022. The primary outcome of the study was overall survival (OS). Forty-three patients, 28 adults and 15 children, with R/R CD1a + T-ALL were included. Median (range) age at inclusion was 24 years (5–57), and 82.5% were male. After a median (range) follow-up of 7.0 years (5.1–13.6), 6 (14.0%) patients were alive and in complete remission (CR) and 37 (86.0%) had died. Five-year OS was 16% (95% CI; 7–29%). Bone marrow relapse, an interval < 12 months between first CR and relapse, and lack of allogeneic hematopoietic stem cell transplantation during salvage treatment were associated with worse OS. Our results confirm that patients with R/R CD1a + T-ALL have a very poor prognosis, highlighting the need for new treatment alternatives in these patients.

Acute myeloid leukemia (AML) includes genetically defined subsets. In allogeneic hematopoietic cell transplantation (allo-HCT), the frequency and prognosis of gene-gene interactions may differ from those of patients treated with chemotherapy alone. In this study, adult patients (N = 952) with AML allografted between 2015 and 2023, with available next generation sequencing (NGS) at diagnosis were included. Most frequent mutations were DNMT3A (24%), FLT3-ITD (21%), NPM1 (21%), RUNX1 (16%), NRAS (16%), TET2 (14%), and IDH2 (12%). Multiple correspondence analysis identified distinct groups of co-occurring mutations. Outcome analysis was performed on 646 AML patients allografted in first complete remission (CR1). Six non-overlapping groups were constructed: 1) TP53 mutation (N = 47); 2) NPM1 mutation (N = 129); 3) FLT3-ITD and/or DNMT3A mutation (N = 128); 4) SRSF2 and/or ASXL1 and/or RUNX1 mutation (SAR group) (N = 132); 5) IDH1 and/or IDH2 and/or TET2 mutation (N = 43); and 6) all ten genes unmutated (N = 167). In multivariable analysis, TP53 mutation, adverse karyotype, and age negatively affected leukemia-free survival (LFS) and overall survival (OS). OS was additionally negatively affected when the ten genes were unmutated. Notably, outcomes were excellent for SAR mutations (2-year LFS 76%, OS 84%), indicating allo-HCT in CR1 can overcome their adverse risk at diagnosis.

BACKGROUND AND OBJECTIVE:In acute myeloid leukemia (AML), cytogenetic alterations have influence on treatment response and are essential for risk stratification, although some have uncertain prognostic relevance. In this study, the prognostic impact of cytogenetic alterations was analyzed in a series of newly diagnosed AML patients treated with risk-adapted protocols. PATIENTS AND METHOD:The cytogenetic profile of 1417 adult patients diagnosed with de novo AML (without t(15;17) or PML::RARA) enrolled in the CETLAM cooperative group protocols from 1994 to 2012 was studied, and its impact on survival was evaluated. RESULTS:Multivariable analysis showed that anomalies such as t(8;21) and inv(16)/t(16;16) predict a favorable prognosis, with no significant effect of additional anomalies on outcome. In contrast, abnormalities like monosomy of chromosome7, structural alterations of chromosome1, complex karyotype (5 or more abnormalities), and monosomal karyotype were associated with worse outcomes. Patients were classified into three prognostic groups based on their cytogenetic alterations, which demonstrated the effectiveness of the proposed system in predicting prognosis. CONCLUSION:This study confirms the prognostic impact of cytogenetic alterations in AML and their usefulness in stratifying patients into risk groups.

Abstract Background Recent advances in next-generation sequencing (NGS) and transcriptomic profiling have refined the molecular classification of B-cell precursor acute lymphoblastic leukemia (BCP-ALL), leading to the identification of novel subtypes with distinct biological features and clinical implications. Among these, the BCR::ABL1-like subtype is characterized by a stem/progenitor cell gene expression profile, poor response to conventional therapy, higher levels of measurable residual disease (MRD), and an increased risk of relapse. Accurate and timely classification of this subtype is crucial for therapeutic decision-making, including the use of tyrosine kinase inhibitors and intensified treatment protocols.AimsOur primary objective was to develop artificial intelligence (AI) models that allow for rapid and automated classification of BCR::ABL1-like BCP-ALL patients using gene expression data obtained from our custom panel. In addition, we aimed to assess whether the combination of gene expression profiles and diagnostic clinical variables could be used to predict adverse outcomes, such as relapse or death, at diagnosis.MethodsRNA-seq data from 179 BCP-ALL patients were quantified using Salmon and normalized across samples. Normalized expression values were used to train predictive models. The dataset was randomly divided into training (80%) and test (20%) subsets. The BCR::ABL1-like subtype was encoded as 1; all other subtypes as 0. Clinical outcome (relapse and death) was available for a subset of 82 patients. Two machine learning (ML) strategies were applied: LightGBM (LGBM, Microsoft®) and a neural network (NN) built with Keras. Hyper-parameter tuning was performed for both models. Prediction accuracy was used to assess classification performance, and ROC_AUC variable (receiver operating characteristic - area under the curve) was used to evaluate outcome prediction, both measured on the test set. Feature importance and SHAP values were computed to interpret the LGBM models Results Both AI models demonstrated strong classification performance, with test set accuracies of 0.96 (LGBM) and 0.98 (NN). No overfitting was observed (training vs. test accuracy difference < 0.02). For outcome prediction, the LGBM model yielded ROC-AUC values of 0.68 (death) and 0.83 (relapse). The top genes associated with relapse (based on LGBM feature importance) were JCHAIN (8), CD99 (11), and SHOC2 (19). For death, the top features were SHOC2 (17), RBM47 (17), and LDB3 (14). SHAP analysis suggested a protective role for SHOC2 in both relapse (SHAP: –0.70) and death (–0.40), whereas RBM47 (+0.60) and LDB3 (+0.70) were associated with increased mortality risk. Summary/Conclusions AI models trained on targeted RNA-seq gene expression data can reliably classify BCR::ABL1-like BCP-ALL, supporting their potential role in rapid, automated molecular diagnosis. Additionally, baseline gene expression at diagnosis shows promise for predicting clinical outcomes, although larger cohorts are needed to improve prognostic model performance. Preliminary findings highlight SHOC2 as a potential protective biomarker for relapse and mortality in BCP-ALL, while RBM47, LDB3, and CD99 warrant further investigation as markers of poor prognosis.

INTRODUCTION Acquired regions of homozygosity (aROHs), due to mitotic recombination between homologous chromosomes, may contribute to the expansion of a neoplastic clone if they involve mutated tumor suppressor genes (TSGs) or oncogenes (OGs), with subsequent loss of the wild-type allele and duplication of the aberrant one. aROHs can be readily detected across the genome of patients (pts) with B-cell acute lymphoblastic leukemia (B-ALL) by single nucleotide polymorphism (SNP)-array analysis. However, their potential contribution to leukemogenesis remains poorly investigated. Our previous work (Blood (2024) 144 (Supplement 1): 2844) demonstrated the recurrence of aROHs in a large cohort of adult Philadelphia chromosome-negative (Ph-) B-ALL pts enrolled in the PETHEMA LAL-19 trial (NCT 04179929). Most of these alterations did not involve genes related to B-ALL leukemogenesis and, according to conventional statistical analyses, did not impact prognosis. On the contrary, due to their association with a low rate of mutation and with preserved diploidy, we hypothesized aROHs without driver genes for B-ALL could play a beneficial role for the genome integrity, although this was not reflected in pts' survival. Based on these contradictory findings, we aimed to evaluate if these aberrations could actually have a prognostic impact through a machine learning-mediated approach. METHODS aROHs were identified by SNP-array analysis on DNA extracted from infiltrated bone marrow, using the CytoScan™ 750K platform, according to the manufacturer's instructions (ThermoFisher Scientific, MA, USA). Briefly, ROHs ≥3 Mb in size, not associated with copy number variations, located in regions covered by ≥20 consecutive probes and not overlapping germline polymorphisms in ≥50% of their length were selected to identify only putatively acquired events. Following conventional statistical analysis, we designed an analytical strategy using the LightGBM machine learning model provided by Microsoft (WA, USA). Death and relapse were predefined as target variables (TVs), and the ability of aROHs to predict these two outcomes was assessed. Based on the median follow-up (FU) of the cohort, a survival time cutoff was established at 60, 100, and 180 days (d), and six predictive models for the TVs were generated (one for each cut-off). Each model included an average of 37 informative clinical and molecular variables (range: 29–43), including the total size of aROHs per pt (ΣaROHs/pt), the involvement of pan cancer TSGs and OGs within aROHs, and their possible extension to telomeres. Multiple rounds of hyperparameter tuning were performed using grid search combined with an 80/20 cross-validation split to identify the best-performing predictive model in each case. RESULTS We previously described a total of 332 aROHs in 156/277 pts (56%), included in our study from December 2019 to March 2024, with a median FU of 17 months. Median age was 40 years (range 18-60). The male/female ratio was 1:1. 94 % of aROHs were segmental, distributed across the whole genome. Involvement of pan cancer TSGs, OGs and telomeres was reported in 44%, 57% and 19% of cases, respectively. Based on the ROC curves derived from the six models using the survival time cut-offs previously described, d+100 was identified as the most effective time point for accurate prediction of the TVs. The study assessing the prognostic weight at d+100 of informative variables, based on absolute values, demonstrated that ΣaROHs/pt was the most important factor (importances 22 and 7 for death and relapse, respectively), after minimal residual disease (MRD) levels at the end of induction (end-Ind) (importances 45 and 27 for death and relapse, respectively). Spearman's correlation analysis revealed that ΣaROHs/pt was strongly negatively associated with both the risk of relapse and the risk of death (Spearman's ρ: death –0.1 for ΣaROHs/pt vs. +0.3 for MRD positivity at end-Ind; relapse –0.6 for ΣaROHs/pt vs. +0.6 for MRD positivity at end-Ind). In contrast, the presence of pan-cancer TSGs, OGs, and telomeric regions within aROHs was only marginally associated with an increased risk of both events. CONCLUSIONS Our machine-learning mediated approach revealed that ΣaROHs/pt may represent an important variable for early risk stratification of Ph- B-ALL pts, with favorable impact on their survival.

Introduction: Current treatment strategy for HIV-associated Burkitt lymphoma (BL) typically rely on intensive chemotherapy regimens modeled on anti-leukemia protocols such as GMALL, LMB, and their regional derivatives. These are often resource-intensive, prolonged, and associated with dose-limiting toxicities, frequent interruptions, and high treatment-related mortality. The “CARMEN” protocol is a dose-dense regimen developed to improve tolerability while maintaining efficacy [Ferreri, Blood Adv 2022]. It includes a 36-day, single-course induction with weekly sequential doses of six anticancer drugs, plus intrathecal chemo, followed by high-dose cytarabine–based consolidation. Favorable safety and efficacy profiles with CARMEN and similar regimens have helped narrow the outcome gap between HIV-pos and HIV-neg patients (pts) with BL. However, systematic comparisons of efficacy across chemo regimens—particularly when stratified by prognostic scores—remain limited. In the absence of feasible prospective comparative trials, the HIV Lymphoma Network of the European Hematology Association launched an international study to assess feasibility and efficacy of GMALL (and its derivatives), CARMEN, and other regimens in HIV-pos pts with BL treated at 19 centers across Germany, Italy, Spain, France, and Croatia. Methods: HIV-pos adults with BL treated between 2005–2024 were included. All pts were eligible regardless of ECOG PS, stage, IPI, BLIPI [Olszewski, JCO 2021], or treatment. Pts with HBV/HCV infection were included; those lost to follow-up within 6 months of diagnosis were excluded. The primary endpoint was overall survival (OS), analyzed by treatment regimen and stratified by IPI (low: 0–1; intermediate: 2–3; high: 4–5) and BLIPI (low: 0; intermediate: 1; high: 2–4). Feasibility and tolerability were assessed by the incidence of treatment-related deaths, dose reductions or interruptions, grade ≥3 non-hematologic toxicities, and grade ≥3 infections. Variables significantly associated with OS were further evaluated using Cox proportional hazards models. Results: Of 247 consecutive HIV-pos pts with BL (median age 43; range 25–68; 227 males), 16 were excluded for early loss to follow-up, leaving 231 for analysis. Of these, 145 received GMALL or derivatives (BFM, BURKIMAB), 41 received CARMEN, 16 received LMB, and 20 received R-CHOP. Nine pts treated with other regimens were excluded from analyses. Baseline characteristics were comparable across groups, except for B symptoms, which were not recorded in the LMB cohort. At a median follow-up of 65 months (range 7–164), 73 pts experienced a PFS event, and 61 died: 41 from lymphoma, 17 from infections, and 2 from second cancers. The 5-yr PFS and OS were 70% (95%CI:69–71) and 71% (95%CI:70–72), respectively. Stratified by treatment regimen, 5-yr OS was 74% (95%CI:73–75) for GMALL and derivatives, 68% (95%CI:66–70) for CARMEN, 79% (95%CI:78–80) for LMB, and 45% (95%CI:25–62) for R-CHOP. IPI data were available for 212 pts (95%). Among 49 with IPI 0–1, only two events occurred, with a 5-yr OS of 95% (95%CI:94–96) and no significant differences across regimens. Among 163 pts with IPI 2–5, the 5-yr OS was 65% (95%CI:64–66), with comparable efficacy among GMALL and derivatives, CARMEN, and LMB, but significantly worse outcomes for R-CHOP. Similar findings were observed using BLIPI stratification. Multivariable analysis identified bulky disease, HIV-RNA levels, gender, and IPI as independent OS predictors. Notably, it confirmed equivalent efficacy among intensified regimens and their superiority over R-CHOP. In terms of feasibility, CARMEN had the most favorable profile: only 5 pts (12%) required dose reductions and 2 (5%) discontinued treatment due to toxicity. In comparison, dose reductions and discontinuations occurred in 30% and 16% of pts on GMALL, and 38% and 16% with LMB. Conclusions: OS rates are encouraging in HIV-pos pts with BL; however, nearly one-third of deaths are still attributable to iatrogenic toxicity. Despite the limitations of a retrospective design, our findings suggest that CARMEN regimen provides outcomes comparable to those of standard intensive protocols (GMALL, its derivatives, and LMB). Efficacy was consistent across all risk subgroups defined by IPI and BLIPI. In addition to its short duration and favorable tolerability, CARMEN may reduce the risk of chronic toxicity and secondary malignancies, owing to its use of single doses of chemotherapeutic agents.

ABSTRACT:Relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) remains a challenging disease with dismal prognosis. Despite the revolutionary impact of CD19-directed chimeric antigen receptor (CAR19) T-cell therapy, >50% of patients relapse within a year. Both leukemia cell-intrinsic factors favoring immune escape and poor CAR T-cell persistence contribute to clinical failure. Moreover, the expression of immune checkpoint receptors (ICRs) and their ligands within the bone marrow (BM) microenvironment may contribute to leukemia progression and therapy resistance. Here, we characterized the expression of ICRs and their ligands in leukemic blasts, T cells, and mesenchymal stromal cells (MSCs) from B-ALL BM samples at diagnosis and relapse, comparing them with age-matched healthy BM controls. Our findings reveal a significantly upregulated expression of TIM-3 in T cells and its ligand, galectin-9, in both blasts and MSCs throughout disease progression. The expression of galectin-9 in B-ALL blasts and TIM-3 in CAR19 T cells negatively correlates with clinical outcome. Furthermore, we demonstrate that galectin-9 impairs CAR19 T-cell homeostasis and cytotoxicity. Notably, an engineered TIM-3-Fc decoy receptor, delivered either by primary T cells coadministered with CAR19 T cells or via a bicistronic all-in-one CAR19-TIM-3-Fc construct, improved the antileukemia efficacy and persistence of CAR19 T cells in B-ALL xenograft models. Mechanistically, CAR19-TIM-3-Fc T-cell treatment promotes the in vivo expansion of transduced and bystander effector and memory T cells, as determined by spectral flow cytometry. Collectively, these TIM-3-Fc decoy-armored CAR19 T cells offer a promising therapeutic strategy for patients with R/R B-ALL.

Burkitt lymphoma is a rare lymphoma entity that represents less than 5% of adult lymphomas. Although prognosis has improved with dose-dense therapy, Burkitt lymphoma remains an area of clinical and biological research with specificities due to the high incidence of CNS involvement and tumour lysis syndrome in patients with a high tumour burden. Few consensus recommendations are available concerning diagnosis, treatment, and prognostic factors in adult patients. In this Review, a European Reference Network on Rare Haematological Diseases (ERN-EuroBloodNet) expert panel has reviewed recent advances in the management of Burkitt lymphoma in the first-line setting to develop updated evidence-based and expert opinion-based recommendations on the management of this disease. The expert panel consisted of ten clinicians and pathologists involved in the clinical management of Burkitt lymphoma from eight EU member states. Additionally, two haematologists were included to support the systematic review process. A balanced representation was ensured between individuals affiliated and not affiliated with ERN-EuroBloodNet. Together with providing current indications on diagnosis and risk-adapted first-line therapy, the Review contains specific recommendations for the identification and management of important complications of Burkitt lymphoma such as tumour lysis syndrome and CNS-oriented therapy, and recommendations for prognostic assessment to guide treatment. Finally, unresolved questions for Burkitt lymphoma are highlighted, including questions around genetics, imaging, and second-line therapies, along with patient perspective.

BACKGROUND:Philadelphia chromosome-positive acute lymphoblastic leukemia has historically been associated with poor prognosis and limited therapeutic options. Over the past 2 decades, however, the treatment paradigm has markedly shifted. SUMMARY:The introduction of tyrosine kinase inhibitors (TKIs), such as imatinib, dasatinib, and ponatinib, has revolutionized frontline therapy, significantly improving remission rates and long-term survival. These agents, when combined with reduced-intensity chemotherapy or even with corticosteroids, have enabled less toxic regimens, particularly beneficial for older or unfit patients. The implementation of measurable residual disease monitoring has emerged as a pivotal tool for risk stratification and therapeutic decision-making. Consequently, the role of allogeneic hematopoietic stem cell transplantation, considered a cornerstone of curative treatment, is being reevaluated in patients achieving sustained deep molecular responses. More recently, immunotherapeutic strategies - including the bispecific T-cell engager blinatumomab and chimeric antigen receptor (CAR) T-cell therapies - have emerged as effective alternatives to conventional chemotherapy and TKIs. KEY MESSAGES:While TKIs remain the backbone of treatment, the integration of immunotherapeutic strategies - including bispecific antibodies and CAR T-cell therapy - has expanded therapeutic options, not only in the R/R setting but increasingly in frontline regimens. Ongoing research aimed at optimizing the sequencing, combination, and duration of these therapies is essential to further enhance clinical outcomes.

In the phase 3 PhALLCON trial (NCT03589326), ponatinib demonstrated superior efficacy, patient-reported treatment tolerability, and health-related quality of life (HRQoL) compared to imatinib in adults with newly diagnosed Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). To explore the association between clinical response and HRQoL and substantiate the superior effect of ponatinib over imatinib on HRQoL, we analyzed the impact of clinical response and treatment tolerability on changes in HRQoL. HRQoL was assessed using the Functional Assessment of Cancer Therapy–Leukemia (FACT-Leu) questionnaire and the EQ-5D-5 L. Treatment tolerability was assessed using the FACT-GP5 item “bothered by treatment side effects.” Linear mixed-effects regression models were used to examine changes in HRQoL over time, with clinical response status and patient-reported overall treatment tolerability as time-varying predictors, while controlling for significant covariates. This analysis included data from 238 patients (159 ponatinib, 79 imatinib). Achieving clinical response (complete remission or incomplete remission) was associated with significantly better changes from baseline across all FACT-Leu domains and the EQ-visual analogue scale than not achieving clinical response (p < 0.05). Treatment-related side effects led to significantly and meaningfully worse changes in HRQoL than “not bothered by treatment,” with higher levels of “bother” associated with greater worsening in HRQoL from baseline. Taken together with the better treatment tolerability and longer response duration of ponatinib compared to imatinib, these findings further substantiate the HRQoL benefit of ponatinib over imatinib in patients with Ph + ALL.

The past decade has witnessed remarkable advances in deciphering the pathophysiology of acute lymphoblastic leukemia (ALL) and in developing novel targeted therapies. Basic research and genomic mapping have identified new prognostic biomarkers, targets, and ALL subtypes (e.g., Philadelphia-like ALL). The ongoing therapeutic revolution in ALL is driven by the addition to the treatment arsenal of therapies that target the ABL fusions, like the BCR::ABL1 tyrosine kinase inhibitors, as well as novel agents that target CD19 and CD22: the CD22 antibody-drug conjugate inotuzumab ozogamicin, the bispecific CD3/CD19 T-cell engager antibody blinatumomab, and CD19 chimeric antigen receptor T-cell therapies. These combinations have improved the long-term survival rates in B-cell ALL to 70%, and in Philadelphia chromosome-positive ALL to 80%-90%. The desired goals are to achieve cure rates comparable to those in pediatric ALL and to reduce or eliminate the need for prolonged intensive/maintenance chemotherapy and associated toxicities.

Acute leukemias of ambiguous lineage (ALAL) are an infrequent subtype of acute leukemias without clear evidence of differentiation to a one single cell lineage. Despite their rarity constitute a recognized subgroup in the recent international classifications, such as the WHO (World Health Organization) classification. Their diagnosis require highly specialized flow cytometry technology, and also cytogenetics and molecular techniques. The low frequency of the disease has made it difficult to find the best therapeutic strategy, due both to the lack of prospective studies and randomized trials, and to the heterogeneity of the published retrospective studies on follow-up and treatment. The group of ALAL has bad prognosis, and usually requires intensive strategies that include consolidation with allogeneic stem cell transplant as part of the treatment. The objective of this review was to analyze diagnosis, treatment and prognosis of this rare subtype of leukemias.

PURPOSE:The Precision Oncology Program (POP) in Catalonia aims to provide equitable access to molecular testing for individuals with cancer, integrating Next-Generation Sequencing (NGS) into clinical practice to inform diagnosis, prognosis, and treatment decisions for both adult and pediatric patients with solid and hematologic malignancies, including somatic and germline alterations. This study evaluates the program's outcomes and impact. METHODS:This evaluation covers the period from the program's implementation in July 2021 through December 2023, with a more detailed analysis focusing on 2022-2023. The program involved 12 reference centers utilizing NGS technology for cancer genetic analysis, coordinated by CatSalut, the regional public health service payer. Data collected from each reference laboratory included the number of tests performed, types of tumor panels used, clinical indications, and associated outcomes. RESULTS:Between July 2021 and December 2023, a total of 23,135 molecular tests were performed on 22,501 patients. The most frequently analyzed panels were for solid tumors (38.1%), hematologic cancers (17.3%), and germline mutations (42.2%). Pediatric patients accounted for 2.4% of the total. Notably, 24.7% of patients underwent a change in clinical management, contributing to more targeted treatment strategies, particularly in solid tumors (58.7%). Reports were delivered within an average of four weeks, meeting program benchmarks and facilitating timely decision-making. Sample submission compliance was high, reaching 98.5%. CONCLUSIONS:This POP successfully addressed operational, financial, and logistic challenges, ensuring equitable access to molecular testing. This program led to more efficient and personalized clinical management, with growing impact on cancer care and patient outcomes.

Relapse is the main cause of treatment failure in T-cell acute lymphoblastic leukemia (T-ALL). Despite this, data from adult T-ALL patients treated with specific chemotherapeutic regimens that examine predictive markers and describe relapse mechanisms are scarce. In this study, we studied 74 paired diagnosis-relapse samples from 37 patients homogeneously treated with three consecutive measurable residual disease-oriented trials to identify genetic determinants involved in relapse in adult T-ALL. Analysis of single-nucleotide variants and copy number alterations consistently found N/KRAS mutations (20% relapsed cases) at diagnosis and at relapse (resistance profile). N/KRAS mut patients frequently relapse early during consolidation treatment. Relapse-specific mutations in NT5C2, NR3C1, SMARCA4, and TP53 (40% relapse cases) were not detected at diagnosis by conventional molecular techniques (relapse profile). However, single-cell-based analysis revealed a very minor clone containing the NT5C2(p.R367Q) variant at diagnosis. Patients with the NT5C2(p.R367Q) variant mostly relapse later during maintenance treatment. Tracking the NT5C2 variant by digital PCR confirm the expansion of the NT5C2 clone at maintenance treatment. Overall, our exploratory analysis suggests a role for these genetic events, most of which have already been described in pediatric cases, driving resistance associated to specific chemotherapeutic agents, contributing to the relapse of a high proportion of adult T-ALL patients (60%).

Abstract Introduction. Adults with Ph-negative acute lymphoblastic leukemia (Ph- ALL) may not require allogeneic hematopoietic stem cell transplantation (alloHSCT) if they achieve negative measurable residual disease (MRD) after induction and consolidation therapy. However, it is unclear whether baseline genetic risk could more accurately identify patients (pts) who should receive chemotherapy (CHT) or alloHSCT. The aim of the PETHEMA LAL19 protocol (NCT04179929) was to evaluate the outcomes of pts assigned to differentiated post-induction therapy (CHT or alloHSCT) according to genetic features at diagnosis and MRD levels after induction. Methods. PETHEMA LAL19 was a multicenter study, including data from 94 centers across Spain. It enrolled newly diagnosed Ph-negative ALL pts, both T- and B-lineage, who received a pediatric-inspired treatment. Pts with high-risk (HR) genetics, those requiring two induction cycles to achieve complete remission (CR), and those with CR but MRD ≥0.01% after induction-1 (Ind-1) or MRD ≥0.001% after early consolidation and reinduction were allocated to alloHSCT. The remaining pts, considered standard-risk pts, were assigned to late consolidation and maintenance. HR genetics in B-ALL included: KMT2A rearrangement, hypodiploidy (<40 chromosomes) in pts aged >35 years, homozygous TP53 mutations/deletions, or co-occurrence of IKZF1 and CDKN2A deletions. HR genetics in T-ALL included absence of NOTCH1/FBXW7 mutations and/or mutations in K/NRAS or PTEN. Early T-cell precursor (ETP) ALL pts received a different treatment and all of them were assigned to receive an alloHSCT in first CR. All MRD and genetic studies were centralized. Results. Between end 2019 and August 2024, 436 eligible pts were enrolled (413 non-ETP and 23 ETP). In the non-ETP group, median age was 40 years (range, 18–60), 56% were male, median WBC count was 12×10⁹/L (0.4–740), and 80% had B-ALL. HR genetics were found in 36% (99/274) of B-ALL pts and 52% (34/65) of T-ALL cases. CR rate after Ind-1 was 84% (348/413) and increased to 95% (387/407) after Ind-1+Ind-2. MRD <0.01% was achieved in 63% (221/348) post-Ind-1 and in 91% (324/357) post-Ind-1+Ind-2. In the ETP-ALL group (n=23), median age was 29 years (range, 18-57), 57% were male, median WBC count was 29.2×10⁹/L (3.5-389), and five patients had CNS involvement. The CR rate was 74% (17/23) with 7 (41%) pts being MRD <0.01% after Ind-1 with FLAG-IDA. By intention-to-treat, 243 pts (61%) from the non-ETP group were allocated to alloHSCT and 157 (39%) to CT. The 3-year overall survival (OS) was 64% (95% CI, 58%–69%), and the cumulative incidence of relapse (CIR) was 39% (33%–45%). Among pts with CR and MRD <0.01% after Ind-1 and without HR genetics (n=109), 3-year OS was 81% (70%–89%). This compares favorably with 50% (34%–63%) observed in genetically HR pts (n=64) with similar MRD clearance, as well as with 58% for pts with CR and MRD ≥0.01% and 53% for pts who did not achieve CR after Ind-1 (p<0.001). A very-good risk group of patients (absence of HR genetics & CR after ind-1 with MRD<0.01% & MRD<0.001% after Re-Induction) showed a 3-year OS of 89% (78%–95%) and a 3-year CIR of 19% (10%-31%) with CHT only. In ETP-ALL pts, the 3-year OS was 61% (37%–79%), and the CIR was 25% (8%–48%). Conclusions. In adults with Ph- ALL, assigning post-remission treatment based on MRD and genetic risk is feasible. Genetic risk assessment among pts with good MRD clearance identified a subgroup with excellent prognosis without the need for alloHSCT. Thus, integrating genetic risk with MRD improves the precision of risk stratification.