Best Practice & Research Clinical Haematology最新文献

Lymphoblastic lymphoma (LBL) is the second most common type of non-Hodgkin Lymphoma (NHL) in children, adolescents, and young adults (CAYA), accounting for 25–35% of all cases. T-lymphoblastic lymphoma (T-LBL) comprises 70–80% of cases, while precursor B-lymphoblastic lymphoma (pB-LBL) makes up the remaining 20–25% of cases. Event-free and overall survival (EFS and OS) for paediatric LBL patients both exceed 80% with current therapies. Treatment regimens, especially in T-LBL with large mediastinal tumours, are complex with significant toxicity and long-term complications. Though prognosis overall is good for T-LBL and pB-LBL with upfront therapy, outcomes for patients with relapsed or refractory (r/r) disease remain dismal. Here, we review new understanding about the pathogenesis and biology of LBL, recent clinical results and future directions for therapy, and remaining obstacles to improve outcomes while reducing toxicity.

Post-transplant Lymphoproliferative Disease (PTLD) remains a major complication of solid organ transplantation (SOT) in pediatric patients. The majority are Epstein-Barr Virus (EBV) driven CD20⁺ B-cell proliferations responsive to reduction to immunosuppression and anti-CD20 directed immunotherapy. This review focusses on the epidemiology, role of EBV, clinical presentation, current treatment strategies, adoptive immunotherapy and future research in EBV + PTLD in pediatric patients.

Mature B-cell lymphomas, (B- or T-cell) lymphoblastic lymphomas (LBL), and anaplastic large cell lymphoma (ALCL) correspond to about 90% of all non-Hodgkin lymphoma (NHL) cases occurring in children and adolescents. The remaining 10% encompass a complex group of entities characterized by low/very low incidences, paucity of knowledge in terms of underlying biology in comparison to their adult counterparts, and consequent lack of standardization of care, information on clinical therapeutic efficacy and long-term survival. At the Seventh International Symposium on Childhood, Adolescent and Young Adult NHL, organized on October 20–23, 2022, in New York City, New York, US, we had the opportunity to discuss clinical, pathogenetic, diagnostic, and treatment aspects of certain subtypes of rare B- or T-cell NHL and they will be the topic of this review.

Patients with higher-risk myelodysplastic syndromes (HR-MDS) have poor survival and are in need of more effective therapy options. Hypomethylating agents (HMAs) are the current standard of care and are being studied in combination with a number of novel therapies. Recent evidence, however, has delivered sub-optimal results, prompting the need to revisit patient selection criteria, treatment schedules, and clinical endpoints to better inform future studies and steer endpoints towards those that are clinically meaningful to patients.

Autologous T cells genetically modified with a CD19 chimeric antigen receptor are an effective therapy for children and adults with relapsed or refractory acute lymphoblastic leukemia with initial response rates ranging from 70 to 85%. Unfortunately, about half of these responding patients will subsequently relapse raising the question of whether allogeneic hemopoietic stem cell transplant should be considered as a consolidative therapy. Currently efforts are focused on defining risk factors for relapse to try and develop algorithms predicting which patients may benefit from allogenic transplant.

Quantification of measurable residual disease (MRD) in acute lymphoblastic leukemia (ALL) is a well-established clinical tool used to risk stratify patients during the course of chemotherapy, immunotherapy, and/or transplant therapy. As technologies evolve, the sensitivity for quantifying exceptionally low disease burden using either next generation sequencing (NGS) or next generation flow cytometry (NGF) has improved. It is now possible to detect MRD and quantify it precisely in patients who would previously have been deemed MRD negative by older, lower sensitivity methods. Persistence or recurrence of ALL disease burden above 10⁻⁴ (0.01%) is accepted as the minimum threshold for making clinical decisions, but with NGS and NGF, clinicians now confront decision-making with disease burdens sometimes quantified to as low as 10⁻⁶ (0.0001%, or one leukemia cell in a million leukocytes). Emerging data suggest these higher sensitivity methods are superior for identifying patients at lowest risk for relapse, but it remains controversial whether to institute therapies such as blinatumomab or chimeric antigen receptor (CAR)-T cells or move patients to allogeneic hematopoietic cell transplant (alloHCT) when they have quantifiable disease burden less than 10⁻⁴. With additional evidence to facilitate integration of highly sensitive MRD quantification into clinical care and to contextualize MRD within the genotype of individual patients, it will likely be increasingly possible to identify patients able to avoid alloHCT and potentially even de-escalate therapy.

Acute GVHD occurs in nearly 50% of patients receiving hematopoietic cell transplantation (HCT), and is the major driver of mortality. However, progress in the development of new acute GVHD therapeutics has been slow, in part due to heterogeneity in acute GVHD data collection and interpretation among centers. Herein, we first describe the methods used by the Mount Sinai Acute GVHD International Consortium (MAGIC) to standardize acute GVHD data collection and curation. We then review the utility of serum biomarkers, specifically the MAGIC Algorithm Probability (MAP) that combines two GI biomarkers (ST2 and REG3α) that has been shown to be more accurate than changes in clinical symptom severity after GVHD treatment. We then present preliminary data on the feasibility of a surrogate clinical trial endpoint that combines clinical response and MAP two weeks after treatment. This novel endpoint is an earlier and potentially better predictor of non-relapse mortality than the current gold standard of clinical response four weeks after treatment.

The treatment of acute lymphoblastic leukemia (ALL) has changed significantly over the last decade. With the approval of novel antibody based therapies in the relapsed/refractory setting, many of these agents are starting to be used in the upfront setting in clinical trials for older patients. These results have been impressive, and further trials are underway. Other targeted therapies (i.e. BCL inhibitors) are being explored. This article will discuss the incorporation of novel agents to “replace” chemotherapy in induction.

Despite cure rates approaching 100% for some subsets of patients, survivors of childhood acute lymphoblastic leukemia (ALL) report a multitude of short- and long-term side effects. Indeed, the long-term complications of pediatric ALL treatment regimens can be associated with significant morbidity and mortality. Identifying mitigation strategies and developing more effective, less toxic therapies is a central goal of current research.