Lymphoblastic lymphoma in children and adolescents: review of current challenges and future opportunities

Epidemiological characteristics and influencing factors of acute leukemia in children and adolescents and adults: a large population-based study

OBJECTIVE

To assess the epidemiological characteristics and prognostic factors of acute leukemia (AL) in children and adolescents, and make comparisons between pediatric and adult patients.

METHODS

This retrospective cohort study enrolled AL patients from the Surveillance, Epidemiology, and End Results (SEER) 1975-2016. OS in children and adolescents and adults with AL was compared and analyzed separately by age and AL subtype.

RESULTS

Totally 61,694 AL patients were identified, with 45,411 (73.6%) adults and 16,283 (26.4%) children and adolescents. From 2000 to 2016, the incidence rates of AL [annual percent changes (APC) = 1.2, 95%CI = 0.9-1.6, P < 0.05] and acute lymphoblastic leukemia (ALL) (APC = 1.5, 95%CI = 1.1-1.8, P < 0.05) in children and adolescents were significantly increasing. For adults, AL (APC = 0.9, 95%CI = 0.3-1.5, P < 0.05), ALL (APC = 2.5, 95%CI = 2.0-3.1, P < 0.05) and acute myeloid leukemia (AML) (APC = 0.9, 95%CI = 0.4-1.5, P < 0.05) had significantly elevated incidence rates. Overall survival (OS) in children and adolescents with AL was significantly higher than that in adults with AL (log-rank P < 0.0001). OS in children and adolescents and adults with ALL, AML and AUL decreased with age (all log-rank P < 0.0001). Older age, male sex and black race were risk factors for the survival of children and adolescents and adults with ALL, AML and AUL.

CONCLUSION

From 2000 to 2016, the incidence rates of AL in children and adolescents and adults were increasing. Children and adolescents with AL had significantly better OS than adults with AL, and OS declined with age in both children and adolescents and adults with ALL, AML and AUL.

Differential impact of asparaginase discontinuation on outcomes of children with T-cell acute lymphoblastic leukemia and T-cell lymphoblastic lymphoma

BACKGROUND

Asparaginase is essential for treating T-cell acute lymphoblastic leukemia (T-ALL). Despite the ongoing debate on whether T-ALL and T-cell lymphoblastic lymphoma (T-LBL) are the same disease entity or two distinct diseases, patients with T-LBL often receive the same or similar treatment protocols as those with T-ALL.

METHODS

The outcomes of patients with or without L-asparaginase discontinuation were retrospectively analyzed among four national protocols: Japan Association of Childhood Leukemia Study (JACLS) ALL-02 and ALL-97 for T-ALL and Japanese Pediatric Leukemia/Lymphoma Study Group ALB-NHL03 and JACLS NHL-98 for T-LBL. The hazard ratio (HR) was calculated with the Cox regression model by considering L-asparaginase discontinuation as a time-dependent variable.

RESULTS

In total, 199 patients with T-ALL, and 133 patients with T-LBL were included. L-asparaginase discontinuation compromised event-free survival (EFS) of T-ALL patients (ALL-02: HR 3.32, 95% confidence interval [CI] 1.40-7.90; ALL-97: HR 3.39, 95%CI 1.19-9.67). Conversely, EFS compromise was not detected among T-LBL patients (ALB-NHL03: HR 1.39, 95%CI 0.41-4.68; NHL-98: HR 0.92, 95%CI 0.11-7.60).

CONCLUSION

The effects of L-asparaginase discontinuation differed between T-ALL and T-LBL. We assume that the differential impact results from (1) the inherent differential response to L-asparaginase between them and/or (2) a less stringent assessment of early treatment response in T-LBL than in T-ALL. Given the poor salvage rate of refractory or relapsed T-ALL and T-LBL, optimization of the frontline therapy is critical, and the current study provides a new suggestion for further treatment modifications. However, larger studies in contemporary intensified treatment protocols are required.

The Etiologic Landscape of Lymphoproliferation in Childhood: Proposal for a Diagnostic Approach Exploring from Infections to Inborn Errors of Immunity and Metabolic Diseases

Lymphoproliferation is defined by lymphadenopathy, splenomegaly, hepatomegaly, or lymphocytic organ and tissue infiltration. The most common etiologies of lymphoproliferation are represented by infectious diseases and lymphoid malignancies. However, it is increasingly recognized that lymphoproliferative features can be the presenting sign of rare conditions, including inborn errors of immunity (IEI) and inborn errors of metabolism (IEM). Among IEI, lymphoproliferation is frequently observed in autoimmune lymphoproliferative syndrome (ALPS) and related disorders, common variable immunodeficiency (CVID), activated phosphoinositide 3-kinase δ syndrome, and Epstein-Barr virus (EBV)-related disorders. Gaucher disease and Niemann-Pick disease are the most common IEMs that can present with isolated lymphoproliferative features. Notably, other rare conditions, such as sarcoidosis, Castleman disease, systemic autoimmune diseases, and autoinflammatory disorders, should be considered in the differential diagnosis of patients with persistent lymphoproliferation when infectious and malignant diseases have been reasonably ruled out. The clinical features of lymphoproliferative diseases, as well as the associated clinical findings and data deriving from imaging and first-level laboratory investigations, could significantly help in providing the correct diagnostic suspicion for the underlying etiology. This paper reviews the most relevant diseases associated with lymphoproliferation, including infectious diseases, hematological malignancies, IEI, and IEM. Moreover, some practical indications to orient the initial diagnostic process are provided, and two diagnostic algorithms are proposed for the first-level assessment and the approach to persistent lymphoproliferation, respectively.

[Prognostic analysis of childhood T-lymphoblastic lymphoma treated with leukemia regimen]

OBJECTIVES

To investigate the prognosis of childhood T-lymphoblastic lymphoma (T-LBL) treated with acute lymphoblastic leukemia (ALL) regimen and related influencing factors.

METHODS

A retrospective analysis was performed for the prognostic characteristics of 29 children with T-LBL who were treated with ALL regimen (ALL-2009 or CCCG-ALL-2015 regimen) from May 2010 to May 2022.

RESULTS

The 29 children with T-LBL had a 5-year overall survival (OS) rate of 84%±7% and an event-free survival (EFS) rate of 81%±8%. The children with B systemic symptoms (unexplained fever >38°C for more than 3 days; night sweats; weight loss >10% within 6 months) at initial diagnosis had a lower 5-year EFS rate compared to the children without B symptoms (P<0.05). The children with platelet count >400×109/L and involvement of both mediastinum and lymph nodes at initial diagnosis had lower 5-year OS rates (P<0.05). There were no significant differences in 5-year OS and EFS rates between the children treated with CCCG-ALL-2015 regimen and those treated with ALL-2009 regimen (P>0.05). Compared with the ALL-2009 regimen, the CCCG-ALL-2015 regimen reduced the frequency of high-dose methotrexate chemotherapy and the incidence rate of severe infections (P<0.05).

CONCLUSIONS

The ALL regimen is safe and effective in children with T-LBL. Children with B systemic symptoms, platelet count >400×109/L, and involvement of both mediastinum and lymph nodes at initial diagnosis tend to have a poor prognosis. Reduction in the frequency of high-dose methotrexate chemotherapy can reduce the incidence rate of severe infections, but it does not affect prognosis.

Relapsed/Refractory T- Acute Lymphoblastic Leukemia - Current Options and Future Directions

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. The T-cell subtype (T-ALL) accounts for 10-15% of pediatric ALL cases and has been historically associated with outcomes inferior to those of B-cell ALL (B-ALL). The prognosis of T-ALL has significantly improved with contemporary intensive pediatric regimens. However, most children with relapsed T-ALL have dismal outcomes and fewer therapeutic salvage options than those available for B-ALL. After demonstrating efficacy in relapsed T-ALL, nelarabine is being increasingly incorporated into frontline T-ALL regimens. The development of genomic sequencing has led to the identification of new T-ALL subgroups and potential targeted therapeutic approaches which could improve patients' outcomes and reduce the toxicity associated with current therapy. Immunotherapy and cellular therapy regimens are also under early investigation in T-cell malignancies. This review outlines the clinical and biological characteristics of T-ALL and provides an overview of novel treatment options for refractory and relapsed T-ALL.

Genomic signatures and prognosis of advanced stage Chinese pediatric T cell lymphoblastic lymphoma by whole exome sequencing

Objective

To investigate the genomic signatures and prognosis of advanced-stage T cell lymphoblastic lymphoma (T-LBL) and to examine the relationship between T-LBL and T cell acute lymphoblastic leukemia (T-ALL).

Methods

35 Chinese T-LBL children with stage III or IV disease were recruited for this study. They were treated with combination chemotherapy and whole exome sequencing. The relationship of the clinical features, prognosis and specific gene mutations was researched. Gene chips of T-LBL and T-ALL were downloaded from a database, and differential gene expression was analyzed.

Results

Germline causal gene mutations (CARS or MAP2K2) were detected in 2 patients; 3.06 ± 2.21 somatic causal gene mutations were identified in the 35 patients, and somatic mutations were observed in the NOTCH1, FBXW7, PHF6 and JAK3 genes. NOTCH1 mutations were significantly associated with FBXW7 mutations, and the age at diagnosis of patients with NOTCH1-FBXW7 mutations was less than that of patients without such mutations (P < 0.05). 32 patients achieved complete remission (CR), and 14 and 18 patients were classified into the intermediate risk (IR) group and high risk (HR) group. During a median follow-up of 44 months, 3 patients relapsed. Three-year prospective event free survival (pEFS) was 82.286%, and no significant differences of pEFS were found for different sexes, ages, or statuses of NOTCH1-FBXW7 mutations, (P > 0.05); however, the mean survival time of the IR group was longer than that of the HR group (P < 0.05). Differential expression of genes in the T-LBL and/or T-ALL datasets was analyzed using the R package limma, and 1/3 of the differentially expressed genes were found in both the T-ALL and T-LBL datasets. High expression of PI3K-Akt signal pathway genes and the USP34 gene was found in the T-LBL dataset.

Conclusion

Although T-ALL and T-LBL both originate from precursor T-cells and are considered different manifestations of the same disease and the outcome of T-LBL is favorable when using T-ALL-based chemotherapy, there are differences in the gene distribution between T-LBL and T-ALL. It seems that the PI3K-Akt signaling pathway and the USP34 gene play important roles in T-LBL, but medicines targeting the USP34 gene or the PI3K-Akt pathway may be invalid.

Retracted: Britannin mediates apoptosis and glycolysis of T-cell lymphoblastic lymphoma cells by AMPK-dependent autophagy

The above article, published online on 19 September 2022 in Wiley Online Library (https://onlinelibrary.wiley.com/doi/abs/10.1002/jbt.23211), has been retracted by agreement between the authors, the journal Editor in Chief, Hari Bhat, and Wiley Periodicals, LLC. The article is being retracted at the authors' request because some of the data underlying this article refer to a different cell line from the one reported in it. As a result, the article's conclusions do not accurately reflect the full data and cannot be considered reliable.

Precursor B-cell Lymphoblastic Lymphoma in Children: Hacettepe Experience

The purpose of the study was to review the clinical and pathologic characteristics and treatment results of children with precursor B-cell lymphoblastic lymphoma. Of 530 children diagnosed with non-Hodgkin lymphomas between 2000 and 2021, 39 (7.4%) were identified as having precursor B-cell lymphoblastic lymphoma. Clinical characteristics, pathologic, radiologic, laboratory data, treatments, responses, and overall outcomes were recorded from hospital files and analyzed. The median age of 39 patients (males/females, 23/16) was 8.3 years (range 1.3 to 16.1). The most common sites of involvement were the lymph nodes. At a median follow-up of 55.8 months, 14 patients (35%) had a recurrence of disease (11 stage IV, 3 stage III); 4 were in complete remission with salvage therapies, 9 died of progressive disease and one died due to febrile neutropenia. Five-year event-free survival and overall survival rates were 65.4% and 78.3% for all cases, respectively. Survival rates were higher in patients with a complete remission at the end of induction therapies. The survival rates were lower in our study compared with other studies, which could be explained by the high relapse rate and higher incidence of advanced-stage disease due to bone marrow involvement. We demonstrated a prognostic impact of treatment response at the end of the induction phase. Cases with a disease relapse have poor prognosis.

Our Experiences with Asparaginase Activity Measurements in Children with Lymphoblastic Diseases

BACKGROUND

Asparaginase is a key component of chemotherapy protocols for the treatment of lymphoblastic malignancies among children. Adequate asparagine depletion is an important factor to achieve optimal therapeutic outcomes.

METHODS

Over a 3.5 year period, 106 patients were monitored for asparaginase activity (329 samples) in a single center of the Hungarian Pediatric Oncology-Hematology Group. In Hungary, three asparaginase products are available: native E. coli ASNase (Kidrolase), a pegylated form of this enzyme (Pegaspargase) and another native product from Erwinia chrysanthemi (Erwinase). A retrospective data analysis was performed.

RESULTS

In 81% (268/329) of our patients, AEA levels were in the optimal therapeutic range of over 100 IU/L. Of 106 patients, 13 (12%) were diagnosed with 'silent inactivation'.

CONCLUSIONS

Monitoring of AEA can help to identify patients with 'silent inactivation' and their asparaginase therapy can thus be optimized.

Multi-targeted immunotherapeutics to treat B cell malignancies

The concept of multi-targeted immunotherapeutic systems has propelled the field of cancer immunotherapy into an exciting new era. Multi-effector molecules can be designed to engage with, and alter, the patient's immune system in a plethora of ways. The outcomes can vary from effector cell recruitment and activation upon recognition of a cancer cell, to a multipronged immune checkpoint blockade strategy disallowing evasion of the cancer cells by immune cells, or to direct cancer cell death upon engaging multiple cell surface receptors simultaneously. Here, we review the field of multi-specific immunotherapeutics implemented to treat B cell malignancies. The mechanistically diverse strategies are outlined and discussed; common B cell receptor antigen targeting strategies are outlined and summarized; and the challenges of the field are presented along with optimistic insights for the future.

Pediatric Autologous Hematopoietic Stem Cell Transplantation: Safety, Efficacy, and Patient Outcomes. Literature Review

Autologous stem cell transplantation (auto-HSCT) is a part of the therapeutic strategy for various oncohematological diseases. The auto-HSCT procedure enables hematological recovery after high-dose chemotherapy, otherwise not tolerable, by the infusion of autologous hematopoietic stem cells. Unlike allogeneic transplant (allo-HSCT), auto-HSCT has the advantage of lacking acute-graft-versus-host disease (GVHD) and prolonged immunosuppression, however, these advantages are counterbalanced by the absence of graft-versus-leukemia. Moreover, in hematological malignancies, the autologous hematopoietic stem cell source may be contaminated by neoplastic cells, leading to disease reappearance. In recent years, allogeneic transplant-related mortality (TRM) has progressively decreased, almost approaching auto-TRM, and many alternative donor sources are available for the majority of patients eligible for transplant procedures. In adults, the role of auto-HSCT compared to conventional chemotherapy (CT) in hematological malignancies has been well defined in many extended randomized trials; however, such trials are lacking in pediatric cohorts. Therefore, the role of auto-HSCT in pediatric oncohematology is limited, in both first- and second-line therapies and still remains to be defined. Nowadays, the accurate stratification in risk groups, according to the biological characteristics of the tumors and therapy response, and the introduction of new biological therapies, have to be taken into account in order to assign auto-HSCT a precise role in the therapeutic strategies, also considering that in the developmental age, auto-HSCT has a clear advantage over allo-HSCT, in terms of late sequelae, such as organ damage and second neoplasms. The purpose of this review is to report the results obtained with auto-HSCT in the different pediatric oncohematological diseases, focusing on the most significant literature data in the context of the various diseases and discussing this data in the light of the current therapeutic landscape.

Improving outcomes of childhood and young adult non-Hodgkin lymphoma: 25 years of research and collaboration within the framework of the European Intergroup for Childhood Non-Hodgkin Lymphoma

The European Intergroup for Childhood Non-Hodgkin Lymphoma (EICNHL) was established 25 years ago with the goal to facilitate clinical trials and research collaborations in the field both within Europe and worldwide. Since its inception, much progress has been made whereby major improvements in outcomes have been achieved. In this Review, we describe the different diagnostic entities of non-Hodgkin lymphoma in children and young adults describing key features of each entity and outlining clinical achievements made in the context of the EICNHL framework. Furthermore, we provide an overview of advances in biopathology with an emphasis on the role of biological studies and how they have shaped available treatments. Finally, for each entity, we describe future goals, upcoming clinical trials, and highlight areas of research that require our focus going forward.

Cutaneous Metastasis of Alveolar Rhabdomyosarcoma in a Child

ABSTRACT

Rhabdomyosarcoma (RMS) is one of the most common soft tissue sarcomas in children. This lesion is classically included in the generic group of "small round blue cell tumors" along with other entities that share similar microscopic features. Although the head and neck region is a frequent site for primary tumors, cutaneous metastases of RMS involving this anatomical location are rare in the pediatric population. We report a case of a 12-year old girl previously diagnosed with a primary alveolar RMS involving the left maxillary sinus, presenting with a metastatic lesion on the skin of the left temple area. Along with a brief review of the previous case reports on the topic, we highlight the initial immunohistochemistry panel useful for diagnosing this tumor.

Cardiac involvement in a patient with B-cell lymphoblastic lymphoma/acute lymphoblastic leukemia and a history of allogeneic hematopoietic stem cell transplantation and CAR T-cell therapy: A case report

Cardiac involvement in hematological malignancies is uncommon, with only a few cases reported to date, and it often leads to a poor prognosis. Here, we report a case of a 42-year-old woman with a history of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and anti-CD19 chimeric antigen receptor (CAR) T-cell therapy for B-cell lymphoblastic lymphoma/acute lymphoblastic leukemia in whom cardiac mass and myocardial infiltration were detected. Prior to this presentation, massive pericardial effusion had occurred 6 months after CAR T-cell therapy, which was improved via ultrasound-guided pericardiocentesis. We observed elevated cytokine levels and increased copy number of CAR DNA in both pericardial effusion and serum. Upon detecting cardiac mass and myocardial infiltration, the patient was administered tocilizumab (a humanized monoclonal antibody against IL-6 receptor), which controlled the serum cytokine levels, and reduced intensity chemotherapy, including vindesine, cyclophosphamide, and prednisolone. However, the patient finally died of multiple organ failure. To the best of our knowledge, this is the first report on the development of a cardiac mass and occurrence of myocardial infiltration after allo-HSCT and CAR T-cell therapy. This report may provide supporting data for the early diagnosis and immediate treatment of patients with cardiac involvement.

Infectious events in pediatric patients with acute lymphoblastic leukemia/lymphoma undergoing evaluation for fever without severe neutropenia

BACKGROUND

Infections cause significant treatment-related morbidity during pediatric acute lymphoblastic leukemia/lymphoma (ALL/LLy) therapy. Fevers during periods without severe neutropenia are common, but etiologies are not well-described. This study sought to describe the bloodstream infection (BSI) and non-BSI risk in children undergoing therapy for ALL/LLy.

METHODS

Demographic and clinical data were abstracted for febrile episodes without severe neutropenia at two children's hospitals. Treatment courses were stratified by intensity. Multivariate logistic regression evaluated characteristics associated with infection.

RESULTS

There were 1591 febrile episodes experienced by 524 patients. Of these, 536 (34%) episodes had ≥1 infection; BSI occurred in 30 (1.9%) episodes. No BSIs occurred in episodes with a recent procedural sedation or cytarabine exposure. Presence of hypotension, chills/rigors, higher temperature, and infant phenotype were independently associated with BSI (p < .05). Of the 572 non-BSIs, the most common was upper respiratory infection (URI) (n = 381, 67%). Compared to episodes without infection, URI symptoms, higher temperature, absolute neutrophil count 500-999/μl, and evaluation during a low-intensity treatment course were more likely to be associated with a non-BSI (p < .05) and inpatient status was less likely to be associated with a non-BSI (p < .05).

CONCLUSIONS

The BSI rate in pediatric patients with ALL/LLy and fever without severe neutropenia is low, but one-third of the time, patients have a non-BSI. Future research should test if the need for empiric antibiotics can be tailored based on the associations identified in this study.

SOHO State of the Art Updates and Next Questions | Novel Approaches to Pediatric T-cell ALL and T-Lymphoblastic Lymphoma

While outcomes for children with T-cell acute lymphoblastic leukemia (T-ALL) and T-lymphoblastic lymphoma (T-LL) have improved significantly with contemporary therapy, outcomes for patients with relapsed or refractory (r/r) disease remain dismal. Improved risk stratification and the incorporation of novel therapeutics have the potential to improve outcomes further in T-ALL/T-LL by limiting relapse risk and improving salvage rates for those with r/r disease. In this review we will discuss the challenges and new opportunities for improved risk stratification in T-ALL and T-LL. We will further discuss the recent incorporation of the novel therapeutics nelarabine and bortezomib into front-line therapy for children with T-ALL and T-LL. Finally, we will address new classes of targeted small molecule inhibitors, immunotherapeutics, and chimeric antigen receptor T-cell therapies under investigation in r/r T-ALL and T-LL.

PET/CT Evaluation of the Effect of Allogeneic Hematopoietic Stem Cell Transplantation in the Treatment of T-Cell Lymphoblastic Lymphoma

The aim of this study was to investigate the clinical value of positron emission tomography/computerized tomography scanning (PET/CT) in the evaluation of the effect of allogeneic hematopoietic stem cell transplantation in the treatment of T lymphoblastic lymphoma. 12 relevant research articles were collected through layer-by-layer screening in large databases such as Pubmed, Baidu Scholar, and China How Net, and analyzed and summarized using indicators such as progression-free survival (PFS), overall survival (OS), hazard ratio (HR), maximum standardized uptake value (SUV max), total metabolic tumor volume (TMTV), total lesion glycolysis (TLG), elevated lactate dehydrogenase (LDH), and β2-microglobulin (β2-MG). The results showed that before treatment, 18F-FDG PET/CT baseline diagnosis could accurately stage the patients; during treatment, 18F-FDG PET/CT detection could provide effective treatment information; and after treatment, complications were found during 18F-FDG PET/CT detection. In summary, 18F-FDG PET/CT can monitor and evaluate treatment prognosis at baseline, middle, and late stages, and 18F-FDG PET/CT has become an indispensable and important examination technique in clinical work.

Polo-like Kinase 4: the Variation During Therapy and its Relation to Treatment Response and Prognostic Risk Stratification in Childhood Acute Lymphoblastic Leukemia Patients

Polo-like kinase 4 (PLK4) plays an essential role in the tumorigenesis of some blood malignancies; consequently, we hypothesized that PLK4 might serve as a potential biomarker in childhood acute lymphoblastic leukemia (ALL) patients. Therefore, this study investigated the expression of PLK4 and its clinical relevance in childhood ALL patients. Bone marrow specimens were collected from 95 childhood ALL patients and 20 primary immune thrombocytopenia patients (as controls), and their PLK4 expression (reverse transcription-quantitative polymerase chain reaction) was measured after enrollment. Besides, the PLK4 expression in childhood ALL patients was also determined at day 15 after the initiation of induction therapy (D15). PLK4 was increased in childhood ALL patients compared with controls (2.830 (interquartile range (IQR): 1.890-3.660) versus 0.976 (IQR: 0.670-1.288), P≤0.001). PLK4 at diagnosis was elevated in T cell acute lymphoblastic leukemia patients than in B cell acute lymphoblastic leukemia patients (P=0.027). Besides, PLK4 at diagnosis was positively linked with the Chinese Medical Association risk stratification (P=0.016), but not with prednisone response (P=0.077) or bone marrow response (P=0.083). In addition, PLK4 was decreased at D15 after treatment compared with at diagnosis (P≤0.001). Interestingly, PLK4 at D15 (P=0.033) was elevated in T cell acute lymphoblastic leukemia patients than in B cell acute lymphoblastic leukemia patients. Furthermore, increased PLK4 at D15 was associated with poor prednisone response (P=0.018), poor bone marrow response (P=0.034), and increased the Chinese Medical Association risk stratification (P=0.015). In terms of prognosis, high PLK4 was associated with shorter event-free survival (P=0.020), whereas it was not related to the overall survival (P=0.135). In conclusion, PLK4 has the potential as a biomarker for treatment response and prognostic risk stratification of childhood ALL patients.

A Bright Horizon: Immunotherapy for Pediatric T-Cell Malignancies

Immunotherapy has transformed the treatment of hematologic malignancies in the past two decades. The treatment of acute lymphoblastic leukemia (ALL), in particular, has been highly impacted by multiple novel immunotherapies. For pediatric patients with T-cell malignancies, translating immunotherapies has proved more challenging due to the complexities of fratricide, risk of product contamination with malignant cells, and concerns over T-cell aplasia. Despite these hurdles, many creative and promising strategies are on the horizon. We review challenges in the development of immunotherapy for T-cell malignancies, strategies to overcome these challenges, as well as therapies currently being investigated and starting to reach the clinic. Immunotherapy will hopefully successfully treat patients with relapsed and refractory T-cell malignancies and may someday be incorporated in up-front protocols in order to prevent relapses.

Clinical outcomes and prognostic factors in children with B-cell lymphoblastic lymphoma (LBL) treated according to on modified BFM-90 protocol: Experience from a Tertiary cancer care center in India

Pediatric B-cell lymphoblastic lymphoma (LBL) is a rare entity, and appropriate treatment for pediatric B-cell LBL is not well defined. While intensive ALL type regimens achieve long term survival of 90% across Western co-operative group trials, published data from Asian studies on long term outcomes are scarce. We retrospectively analyzed the data of pediatric B-cell LBL patients treated between January 2010 and December 2017 on a uniform protocol (modified BFM 90). Kaplan-Meier method was used to estimate the survival and Cox regression models to identify prognostic factors. Of 21 patients who received treatment on the modified BFM-90 protocol, 17(81%) were alive in remission, 3(14%) had relapse, and 1(4%) had treatment-related mortality (TRM) while in remission. Two of 3 relapsed patients subsequently expired. With a median follow-up of 66 months (range 6-114), 5-year event free survival (EFS) and overall survival (OS) were 80% (95% CI:71-89%) and 91% (95% CI:85-97%), respectively. While delayed presentation from symptom onset (p=0.030), and partial response at early (D35) interim assessment (p=0.025) had inferior EFS, patients with elevated baseline LDH had a worse OS (p=0.037). Outcomes of pediatric B-cell LBL patients treated on a modified BFM-90 protocol at a single center in India were excellent. In our study, higher disease burden manifested by elevated baseline LDH and delayed presentation (≥3months) and partial interim response portend poorer survival.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2021.2005725.

Extranodal Biphenotypic Non-Hodgkin Lymphoma of the Popliteal Cavity: A Case Report and Review of Literature

Primary soft-tissue lymphoma (PSTL) is a rare extranodal non-Hodgkin lymphoma, characterized by a mass growing within soft-tissue, which is connective tissue, adipose tissue, and skeletal muscle. Here, we describe a case of biphenotypic lymphoblastic lymphoma arising from soft tissue of the popliteal fossa in an 11-year-old boy. A pediatric review about PSTL revealed that anaplastic large cell lymphoma is the most common histological type and a biphenotypic lymphoblastic lymphoma has not yet been reported in childhood. Lymphoma should always be considered in patients presenting with a soft-tissue mass, and a comprehensive immunohistochemical evaluation, including B-cell, T-cell, and myeloid markers, is needed to make a correct diagnosis and establish the most suitable treatment.

The role of EphA7 in different tumors

Ephrin receptor A7 (EphA7) is a member of the Eph receptor family. It is widely involved in signal transduction between cells, regulates cell proliferation and differentiation, and participates in developing neural tubes and brain. In addition, EphA7 also has a dual role of tumor promoter and tumor suppressor. It can participate in cell proliferation, migration and apoptosis through various mechanisms, and affect tumor differentiation, staging and prognosis. EphA7 may be a potential diagnostic marker and tumor treatment target. This article reviews the effects of EphA7 on a variety of tumor biological processes and pathological characteristics, as well as specific effects and regulatory mechanisms.

Management of Aggressive Non-Hodgkin Lymphomas in the Pediatric, Adolescent, and Young Adult Population: An Adult vs. Pediatric Perspective

Simple Summary

This review details the diagnosis and treatment of primary non-Hodgkin lymphoma (NHL) in the pediatric and adolescent population. We also describe treatment modalities such as hematopoietic stem cell transplantation for relapsed or refractory NHL in patients that fail or do not respond to the initial therapy. We then detail the current advancements in treatment for patients that fail initial therapy such as CAR T-cell therapy, the use of immunotherapy that target surface makers on malignant cells and highlight areas where further research is needed. The purpose of our review is to inform the pediatric oncology community in regard to the various types of NHLs and emphasize areas where the science is evolving in the treatment of primary, relapsed or refractory disease.

Abstract

Non-Hodgkin lymphoma (NHL) is a broad entity which comprises a number of different types of lymphomatous malignancies. In the pediatric and adolescent population, the type and prognosis of NHL varies by age and gender. In comparison to adults, pediatric and adolescent patients generally have better outcomes following treatment for primary NHL. However, relapsed/refractory (R/R) disease is associated with poorer outcomes in many types of NHL such as diffuse large B cell lymphoma and Burkitt lymphoma. Newer therapies have been approved in the use of primary NHL in the pediatric and adolescent population such as Rituximab and other therapies such as chimeric antigen receptor T-cell (CAR T-cell) therapy are under investigation for the treatment of R/R NHL. In this review, we feature the characteristics, diagnosis, and treatments of the most common NHLs in the pediatric and adolescent population and also highlight the differences that exist between pediatric and adult disease. We then detail the areas of treatment advances such as immunotherapy with CAR T-cells, brentuximab vedotin, and blinatumomab as well as cell cycle inhibitors and describe areas where further research is needed. The aim of this review is to juxtapose established research regarding pediatric and adolescent NHL with recent advancements as well as highlight treatment gaps where more investigation is needed.

iTRAQ-Based Proteomic Analysis Reveals Potential Serum Biomarkers for Pediatric Non-Hodgkin's Lymphoma

Non-Hodgkin’s lymphoma (NHL) is the third most common malignant tumor among children. However, at initial NHL diagnosis, most cases are at an advanced stage because of nonspecific clinical manifestations and currently limited diagnostic methods. This study aimed to screen and verify potential serum biomarkers of pediatric NHL using isobaric tags for relative and absolute quantification (iTRAQ)-based proteomic analysis. Serum protein expression profiles from children with B-NHL (n=20) and T-NHL (n=20) and healthy controls (n=20) were detected by utilizing iTRAQ in combination with two-dimensional liquid chromatography-tandem mass spectrometry (2D LC–MS/MS) and analyzed by applying Ingenuity Pathway Analysis (IPA). The candidate biomarkers S100A8 and LRG1 were further validated by using enzyme-linked immunosorbent assays (ELISAs). Receiver operating characteristic (ROC) analysis based on ELISA data was used to evaluate diagnostic efficacy. In total, 534 proteins were identified twice using iTRAQ combined with 2D LC–MS/MS. Further analysis identified 79 and 73 differentially expressed proteins in B-NHL and T-NHL serum, respectively, compared with control serum according to our defined criteria; 34 proteins were overexpressed and 45 proteins underexpressed in B-NHL, whereas 45 proteins were overexpressed and 28 proteins underexpressed in T-NHL (p < 0.05). IPA demonstrated a variety of signaling pathways, including acute phase response signaling and liver X receptor/retinoid X receptor (LXR/RXR) activation, to be strongly associated with pediatric NHL. S100A8 and LRG1 were elevated in NHL patients compared to normal controls according to ELISA (p < 0.05), which was consistent with iTRAQ results. The areas under the ROC curves of S100A8, LRG1, and the combination of S100A8 and LRG1 were 0.873, 0.898 and 0.970, respectively. Our findings indicate that analysis of the serum proteome using iTRAQ combined with 2D LC–MS/MS is a feasible approach for biomarker discovery. Serum S100A8 and LRG1 are promising candidate biomarkers for pediatric NHL, and these differential proteins illustrate a novel pathogenesis and may be clinically helpful for NHL diagnosis in the future.

Outcomes of children and young adults with T-cell acute lymphoblastic leukemia/lymphoma who present in critical status

BACKGROUND

Patients with T-cell acute lymphoblastic leukemia and lymphoma (T-ALL/LLy) commonly present with critical features such as hyperleukocytosis and mediastinal mass, which complicates completing a diagnostic and staging workup and prevents clinical trial enrollment.

PROCEDURE

Consecutive patients with T-ALL/LLy from 1999 to 2019 at the Children's Hospital of Philadelphia were analyzed for pediatric intensive care unit (PICU) admission and various high-risk features as well as clinical trial enrollment and outcome.

RESULTS

We identified 153 patients newly diagnosed with T-ALL/LLy, 53 (35%) required PICU-level care within 24 hours and 73 (48%) within 7 days. Non-PICU patients had a significantly higher clinical trial enrollment rate (79.4%) versus PICU patients (56.1%, P = 0.016). Patients who enrolled on a clinical trial had similar relapse risk to those who did not enroll (relapse rate 20% vs 29%, P = 0.523). Nineteen patients were precluded from trial participation. Risk of relapse was increased for patients admitted to the PICU within 24 hours (26% vs 13%, P = 0.048). Forty-four patients with T-ALL presented with hyperleukocytosis, of which 30% relapsed versus 14% without (P = 0.082). Patients who underwent apheresis for hyperleukocytosis were statistically more likely to relapse (47% vs 15%, P = 0.007). Patients with elevated uric acid (20% vs 16%, P = 0.278), mediastinal mass (20% vs 14%, P = 0.501), or required emergent steroids (20% vs 16%, P = 0.626) had a similar relapse risk. A single second relapse patient survived.

CONCLUSIONS

Almost half of T-ALL/LLy patients required PICU-level care at diagnosis, making enrollment on clinical trials challenging, but trial enrollment predicted better outcome. Physicians should balance maintaining eligibility with safety to offer patients all options.

T-cell Lymphoblastic Lymphoma in a Patient With Chromosome 8q21.11 Microdeletion

The chromosome 8q21.11 deletion syndrome is an extremely rare genetic condition characterized by facial dysmorphic features, Peters anomaly and impaired intellectual development. We report a case of a 2-year-old female with chromosome 8q21.11-q21.2 microdeletion complicated by T-cell lymphoblastic lymphoma. Whole genome single-nucleotide polymorphism microarray detected an interstitial deletion of 8q21.11 to q.21.2, including 16 genes. Autopsy findings revealed a T-cell lymphoblastic lymphoma presenting as an anterior mediastinal mass, encroaching upon the aortic arch, left subclavian artery, left carotid bifurcation and trachea. The genes that may contribute to a neoplastic process are identified (PKIA, IL7, TPD52, PAG1, and FABP5) and discussed in this article.

Design of a targeted next-generation DNA sequencing panel for pediatric T-cell lymphoblastic lymphoma to unravel biology and optimize treatment

Low incidence and molecular heterogeneity of pediatric T-cell lymphoblastic lymphoma (T-LBL) require an international, large-scale effort to identify novel clinical biomarkers. The ongoing international clinical trial LBL2018 (NCT04043494) represents an ideal opportunity to implement a common analytic approach. Targeted next-generation sequencing is well-suited for this purpose; however, selection of relevant target genes for T-LBL remains subject of ongoing debates. Our group has recently designed and evaluated a first target panel of 80 candidate genes for T-LBL. The present study aimed at developing a novel optimized gene panel for large-scale application and to promote an international agreement on a common core panel. Small sequence variants obtained from our former study were systematically analyzed and classified with regards to pathogenic relevance, to prioritize candidate genes. Additional genes were curated from literature and online databases for a more comprehensive analysis of relevant functions and signaling pathways. The new target panel TGP-T-LBL entails 84 candidate genes which are key actors in NOTCH, PI3K-AKT, JAK-STAT, RAS signaling, epigenetic regulation, transcription, DNA repair, cell cycle regulation and ribosomal function. From our former gene panel, 35 out of 80 candidate genes were selected for the novel panel. Forty-six out of 84 genes are currently being analyzed in the ongoing international trial LBL2018. Exploratory analysis of prognostic relevance on mutation-level suggested a potential association of PIK3CA variants c.1624G > A(p.Glu542Lys) and c.1633G > A(p.Glu545Lys) to occurrence of relapse, emphasizing particular relevance of mutation analysis in PI3K-AKT signaling. Our approach promotes comprehensive and clinically relevant mutational profiling of pediatric T-LBL. This article is protected by copyright. All rights reserved.

A Summary of the Inaugural WHO Classification of Pediatric Tumors: Transitioning from the Optical into the Molecular Era

Pediatric tumors are uncommon, yet are the leading cause of cancer-related death in childhood. Tumor types, molecular characteristics, and pathogenesis are unique, often originating from a single genetic driver event. The specific diagnostic challenges of childhood tumors led to the development of the first World Health Organization (WHO) Classification of Pediatric Tumors. The classification is rooted in a multilayered approach, incorporating morphology, IHC, and molecular characteristics. The volume is organized according to organ sites and provides a single, state-of-the-art compendium of pediatric tumor types. A special emphasis was placed on "blastomas," which variably recapitulate the morphologic maturation of organs from which they originate. SIGNIFICANCE: In this review, we briefly summarize the main features and updates of each chapter of the inaugural WHO Classification of Pediatric Tumors, including its rapid transition from a mostly microscopic into a molecularly driven classification systematically taking recent discoveries in pediatric tumor genomics into account.

Role of TGM2 in T‑cell lymphoblastic lymphoma via regulation of IL‑6/JAK/STAT3 signalling

Transglutaminase 2 (TGM2) is a Ca²⁺-dependent enzyme that is closely associated with cancer progression; however, the function of TGM2 in T-cell lymphoma remains unclear. In the present study, TGM2 was identified as an upregulated gene by bioinformatics analysis of the microarray datasets GSE132550 and GSE143382 from the Gene Expression Omnibus database. The effects and mechanisms of TGM2 on T-cell lymphoma cells were evaluated using the Cell Counting Kit-8, colony formation assay, 5-ethynyl-2′-deoxyuridine (EdU) assay, flow cytometry, reverse transcription-quantitative polymerase chain reaction, western blotting and gene set enrichment analysis (GSEA). TGM2 expression was shown to be elevated in formalin-fixed paraffin-embedded skin biopsies from patients with T-cell lymphoma relative to skin tissue from healthy cases. TGM2 expression was also increased in T-cell lymphoma cell lines compared with that in CD4⁺ T cells. Transfection with TGM2 small interfering RNAs (siRNAs) decreased the number of EdU-positive cells, and the viability and colony formation of T-cell lymphoma cells. Furthermore, TGM2 siRNAs enhanced the apoptosis of T-cell lymphoma cells potentially via cleavage of caspase-3 and poly ADP-ribose polymerase. GSEA identified the IL-6/JAK/STAT3 pathway as a potential downstream signalling pathway of TGM2. Notably, the effects of TGM2 siRNAs on T-cell lymphoma cells were attenuated by IL-6 and accelerated by IL-6/JAK/STAT3 inhibitor AG490. These findings indicated that TGM2 siRNAs inhibited the proliferation of T-cell lymphoma cells by regulating the IL-6/JAK/STAT3 signalling pathway; therefore, TGM2 may function as a potential therapeutic target for T-cell lymphoma.

Extensive pleural involvement in pediatric T-Cell lymphoblastic lymphoma

Lymphoblastic lymphoma (LBL) is the common non-Hodgkin lymphoma in childhood and adolescence. T-cell LBL (T-LBL) usually manifests with an anterior mediastinal mass and disseminated disease. We present a 12-year-old girl with progressive neck swelling and dyspnea for 1 year. Fluorodeoxyglucose positron-emission tomography/computed tomography done for pretreatment staging unveiled hypermetabolic lymph nodes on both sides of the diaphragm with splenic and bone marrow involvement. Apart from these, there was the extensive involvement of the left pleura. Biopsy and immunohistochemistry revealed T-LBL. The extensive secondary pleural involvement in pediatric T-LBL is rarely seen and needs to be reported.

Non Hodgkin Lymphoma Among Children: Pathological Aspects and Diagnostic Challenges

Non-Hodgkin lymphoma (NHL) are common malignancies in children. Available data on clinico-pathological aspects of pediatric NHL in developping countries are limited and diagnostic approach appears more delicate with absence of molecular studies. The objectives of our study are: analyzing the pathological spectrum of NHL among children and highlighting challenges in the diagnosis including: limited biopsic material; unususal subtyptes, age group, or localization. We retrospectively analyzed clinico pathological characteristics of 101 NHL’s cases among children diagnosed in the Pediatric’s pathology unit over a period of 4 years There were 78 (77.2%) male and 23 (22.8%) female. The median age was 7.2 years. The most common histologic subtypes of NHL were Burkitt lymphoma in 65 patients (64.4% ); followed by lymphoblastic lymphoma in 22 patients, large B-cell lymphoma in 9 patients ( 8.9%); anaplastic T cell lymphoma in 3 patients; NOS mature T cell lymphoma and pediatric type follicular lympoma in 1 patient each. In conclusion, this study Morocco illustrates the pattern of distribution of NHL and emphasizes challenges in the diagnosis of these neoplasms.

Post-transplantation Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Patients with Lymphoblastic Lymphoma is an Independent Prognostic Factor with an Impact on Progression-Free Survival but not Overall Survival

Purpose: In the present study, we mainly aimed to evaluate the prognostic value of 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]F-FDG) positron emission tomography (PET)/computed tomography (CT) after allogeneic stem cell transplantation (allo-SCT) in lymphoblastic lymphoma (LBL) patients using Deauville Scores (DS). Materials and Methods: A total of 63 LBL patients who benefited from ¹⁸F-FDG PET-CT after allo-SCT in our institution between April 2010 and August 2020 were enrolled in this retrospective study. These above-mentioned patients were divided into two groups based on the Deauville criteria. Diagnostic efficiency of ¹⁸F-FDG PET/CT and integrated CT in detecting lymphoma were calculated. Consistencies were evaluated by comparing 18F-FDG PET/CT and integrated CT results through kappa coefficient. Kaplan-Meier method was used in survival analysis, and the log-rank method was adopted in comparisons. Prognostic factor analysis was performed by the Cox regression model. Results: The sensitivity, specificity, positive predictive value, negative predictive value, accuracy of post-SCT ¹⁸F-FDG PET-CT were 100%(12/12), 92.2%(47/51), 75.0%(12/16), 100%(47/47) and 93.7%(59/63). The consistency of 18F-FDG PET-CT and integrated CT was moderate(Kappa = .702，P < .001). Positive post-SCT 18F-FDG PET-CT was associated with lower progression-free survival (PFS) but not overall survival (OS) (p = .000 and p = .056, respectively). The 3-year PFS of the PET-positive group and PET-negative group was 18.8% and 70.2%, respectively. Multivariate analysis showed that post-SCT PET-CT findings was an independent prognostic factor for PFS (p = .000; HR, 3.957; 95%CI, 1.839-8.514). Other factors independently affecting PFS were sex (p = .018; HR, 2.588; 95% CI, 1.181 − 5.670) and lactate dehydrogenase (LDH) (p = .005; HR, 3.246; 95% CI, 1.419 − 7.426). However, none of the above-mentioned factors were associated with OS. Conclusions: Collectively, we found that 18F-FDG PET-CT after allo-SCT was a strong indicator for PFS, but not OS, which might provide important evidence for the selection of subsequent treatment regimen for LBL patients. Trial registration number: ChiCTR2100046709.

Other (Non-CNS/Testicular) Extramedullary Localizations of Childhood Relapsed Acute Lymphoblastic Leukemia and Lymphoblastic Lymphoma-A Report from the ALL-REZ Study Group

Children with other extramedullary relapse of acute lymphoblastic leukemia are currently poorly characterized. We aim to assess the prevalence and the clinical, therapeutic and prognostic features of extramedullary localizations other than central nervous system or testis in children with relapse of acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL) treated on a relapsed ALL protocol.

PATIENTS AND METHODS

Patients with relapse of ALL and LBL, treated according to the multicentric ALL-REZ BFM trials between 1983 and 2015, were analyzed for other extramedullary relapse (OEMR) of the disease regarding clinical features, treatment and outcome. Local treatment/irradiation has been recommended on an individual basis and performed only in a minority of patients.

RESULTS

A total of 132 out of 2323 (5.6%) patients with ALL relapse presented with an OEMR (combined bone marrow relapse n = 78; isolated extramedullary relapse n = 54). Compared to the non-OEMR group, patients with OEMR had a higher rate of T-immunophenotype (p < 0.001), a higher rate of LBL (p < 0.001) and a significantly different distribution of time to relapse, i.e., more very early and late relapses compared to the non-OEMR group (p = 0.01). Ten-year probabilities of event-free survival (pEFS) and overall survival (pOS) in non-OEMR vs. OEMR were 0.38 ± 0.01 and 0.32 ± 0.04 (p = 0.0204) vs. 0.45 ± 0.01 and 0.37 ± 0.04 (p = 0.0112), respectively. OEMRs have been classified into five subgroups according to the main affected compartment: lymphatic organs (n = 32, 10y-pEFS 0.50 ± 0.09), mediastinum (n = 35, 10y-pEFS 0.11 ± 0.05), bone (n = 12, 0.17 ± 0.11), skin and glands (n = 21, 0.32 ± 0.11) and other localizations (n = 32, 0.41 ± 0.09). Patients with OEMR and T-lineage ALL/LBL showed a significantly worse 10y-pEFS (0.15 ± 0.04) than those with B-Precursor-ALL (0.49 ± 0.06, p < 0.001). Stratified into standard risk (SR) and high risk (HR) groups, pEFS and pOS of OEMR subgroups were in the expected range whereas the mediastinal subgroup had a significantly worse outcome. Subsequent relapses involved more frequently the bone marrow (58.4%) than isolated extramedullary compartments (41.7%). In multivariate Cox regression, OEMR confers an independent prognostic factor for inferior pEFS and pOS.

CONCLUSION

OEMR is adversely related to prognosis. However, the established risk classification can be applied for all subgroups except mediastinal relapses requiring treatment intensification. Generally, isolated OEMR of T-cell-origin needs an intensified treatment including allogeneic stem cell transplantation (HSCT) as a curative approach independent from time to relapse. Local therapy such as surgery and irradiation may be of benefit in selected cases. The indication needs to be clarified in further investigations.

A Chinese Child Presented with Early T Cell Precursor Lymphoblastic Lymphoma

T cell lymphoblastic lymphoma (T-LBL) is regarded as the leukemic phase of T cell acute lymphoblastic leukemia (T-ALL). The early T cell precursors ALL/LBL (ETP-LBL/ALL) are derived from thymic cells at the ETP differentiation stage and recognized as a high-risk subgroup of T-ALL/LBL. Most of these cases presented with ALL at the disease onset, but the ETP-LBL phase is uncommon. Here, we report a patient who presented with ETP-LBL at the disease onset. In this case, ALL developed even despite receiving chemotherapy, but the patient achieved a complete remission with intensive chemotherapy.

BCR/ABL1-positive B-lymphoblastic Lymphoma Successfully Treated with Dasatinib-combined Chemotherapy

We herein report a rare case of BCR-ABL1-positive B-lymphoblastic lymphoma (B-LBL). An 18-year-old woman had a history of persistent left-sided chest pain. Positron emission tomography showed increased metabolic activity in the fifth rib, duodenum, and pancreas. The pathological findings of the pancreas, duodenum, and bone marrow confirmed the diagnosis of B-LBL. Polymerase chain reaction of duodenum and bone marrow also revealed a minor BCR-ABL1 fusion gene. She was diagnosed with BCR-ABL1-positive B-LBL and administered dasatinib and prednisolone. She achieved complete remission two weeks after the initiation of the treatment. She received stem cell transplantation after consolidation chemotherapy and sustained complete remission.

Pediatric sudden unexpected death due to undiagnosed mediastinal T-cell lymphoblastic lymphoma: A series of three cases

The literature on pediatric sudden unexpected death (SUD) due to unrecognized mediastinal neoplasms is limited to a small number of case reports with several cases confirmed to be secondary to T-cell lymphoblastic lymphoma (T-cell LBL). Mediastinal T-cell LBL can be rapidly progressive and potentially fatal due to the compression and obstruction of the airway and/or the great vessels. The clinical presentation is nonspecific with a predominance of respiratory symptoms that are more apparent when the patient is supine. We presented three cases of pediatric SUD attributed to forensic autopsy-diagnosed anterior mediastinal T- cell LBL. Case 1 involved a 2-year-old girl who presented with 9 days of cough and dyspnea. Postmortem examination revealed a firm rubbery mass surrounding the heart and compressing the bronchi. Case 2 involved a 3-year-old girl who suffered from a respiratory tract infection over several days. Autopsy revealed a firm nodular mass compressing the superior vena cava. Case 3 involved a 2-year-old boy who was found unresponsive, lying prone in his crib. He had cold-like symptoms for several days before his death. Postmortem examination revealed a firm, rubbery anterior mediastinal neoplasm surrounding the superior vena cava and great arteries. These three cases demonstrate the importance of identifying children with mediastinal masses that could potentially lead to life-threatening presentations and pediatric SUD. The forensic pathologist should consider a hematologic neoplasm at the time of autopsy in a previously healthy child who dies suddenly.

Prognostic Role of Minimal Disseminated Disease and NOTCH1/FBXW7 Mutational Status in Children with Lymphoblastic Lymphoma: The AIEOP Experience

NOTCH1/FBXW7 (N/F) mutational status at diagnosis is employed for T-cell lymphoblastic lymphoma (T-LBL) patients’ stratification in the international protocol LBL 2018. Our aim was to validate the prognostic role of Minimal Disseminated Disease (MDD) alone and in combination with N/F mutational status in a large retrospective series of LBL pediatric patients. MDD was analyzed in 132 bone marrow and/or peripheral blood samples by flow cytometry. Mutations in N/F genes were analyzed on 58 T-LBL tumor biopsies. Using the previously established cut-off of 3%, the four-year progression-free survival (PFS) was 57% for stage I–III patients with MDD ≥ 3% versus 80% for patients with MDD inferior to cut-off (p = 0.068). We found a significant worsening in the four-year PFS for nonmutated (51 ± 12%) compared to mutated patients (100%, p = 0.0013). Combining MDD and N/F mutational status in a subgroup of available cases, we found a statistically significant difference in the four-year PFS for different risk groups (p = 0.0012). Overall, our results demonstrate that N/F mutational status has a more relevant prognostic value than MDD at diagnosis. However, the combination of N/F mutations with MDD analysis could identify patients with very aggressive disease, which might benefit from a more intensive treatment.

Ruxolitinib as a Novel Therapeutic Option for Poor Prognosis T-LBL Pediatric Patients

Simple Summary

Current treatment protocols for pediatric patients with T-Lymphoblastic lymphoma (T-LBL) allow the achievement of a complete remission in around 85% of T-LBL pediatric patients; however the overall survival rate of second-line treatments for patients with progressive disease or relapse is around 14%. Thus, the major issues to be addressed are the identification of a valuable predictor marker to foresee the disease risk and new therapeutic targets to improve relapsed/resistant patients’ outcome. We identified JAK2 Y1007-1008 as a potential prognosis marker as well as a therapeutic target for patients with progressive disease or relapse and suggest that its inhibition by ruxolitinib, a JAK1/2 FDA approved inhibitor, could represent a novel therapeutic approach to overcome therapy resistance and meliorate the outcome of pediatric T-LBL patients.

Abstract

Lymphoblastic lymphoma (LBL) is the second most common type of non-Hodgkin lymphoma in childhood, mainly of T cell origin (T-LBL). Although current treatment protocols allow a complete remission in 85% of cases, the second-line treatment overall survival for patients with progressive or relapsed disease is around 14%, making this the major issue to be confronted. Thus, we performed a Reverse Phase Protein Array study in a cohort of 22 T-LBL patients to find reliable disease risk marker(s) and new therapeutic targets to improve pediatric T-LBL patients’ outcome. Interestingly, we pinpointed JAK2 Y1007-1008 as a potential prognosis marker as well as a therapeutic target in poor prognosis patients. Hence, the hyperactivation of the JAK1/2-STAT6 pathway characterizes these latter patients. Moreover, we functionally demonstrated that STAT6 hyperactivation contributes to therapy resistance by binding the glucocorticoid receptor, thus inhibiting its transcriptional activity. This was further confirmed by specific STAT6 gene silencing followed by dexamethasone treatment. Finally, JAK1/2-STAT6 pathway inhibition by ruxolitinib, an FDA approved drug, in cell line models and in one T-LBL primary sample led to cell proliferation reduction and increased apoptosis. Globally, our results identify a new potential prognostic marker and suggest a novel therapeutic approach to overcome therapy resistance in pediatric T-LBL patients.

Dismal outcome of relapsed or primary refractory adult T-cell lymphoblastic lymphoma: A retrospective study from China

AIM

Little is known about the outcome and prognostic factors of relapsed or refractory T-cell lymphoblastic lymphoma (T-LBL), especially in adult patients. The aim of this study was to analyze the characteristics, outcome and prognostic factors for this patient population.

METHODS

Between January 2006 and December 2017, we retrospectively analyzed 84 adult patients with T-LBL, and 44 relapsed or primary refractory patients were included in this analysis. Clinical features, treatment and follow-up information were collected.

RESULTS

For all 44 patients, the median time to disease progression or relapse was 9.5 months after diagnosis. At a median follow-up of 19.6 months, 40 (90.9%) patients died. The 3- and 5-year overall survival (OS) rates after disease progression or relapse were 7.8% and 5.2%, respectively. Among 30 patients who had detailed information of second-line treatment, only eight achieved a second complete remission (CR). Two of these eight patients subsequently underwent autologous or allogeneic stem cell transplantation (SCT), of whom one died from disease progression after autologous SCT, and one was free of event at 84 months after allogeneic SCT. Three of the rest six patients in second CR were still alive after chemotherapy alone. All the remaining patients who failed to gain second CR eventually died. In univariate analysis, only the achievement of second CR was positively predictive of OS (hazard ratio (HR) = 0.307; 95% confidence interval (CI), 0.104-0.905; P = 0.032).

CONCLUSION

The outcome of adult patients with relapsed or refractory T-LBL is extremely dismal. Patients with relapsed or refractory T-LBL should be encouraged to participate in clinical trials where novel therapeutic approaches are available.

Minimal Disease Monitoring in Pediatric Non-Hodgkin's Lymphoma: Current Clinical Application and Future Challenges

Minimal residual disease (MRD) detection is established routine practice for treatment stratification in leukemia and used for treatment optimization in adult lymphomas. Minimal disease studies in childhood non-Hodgkin lymphomas are challenged by stratified treatment in different subtypes, high cure rates, low patient numbers, limited initial tumor material, and early progression. Current clinical applications differ between the subtypes. A prognostic value of minimal disseminated disease (MDD) could not yet be clearly established for lymphoblastic lymphoma using flow cytometry and PCR-based methods for T-cell receptor (TCR) or immunoglobulin (IG) rearrangements. MYC-IGH fusion sequences or IG rearrangements enable minimal disease detection in Burkitt lymphoma and -leukemia. An additional prognostic value of MDD in Burkitt lymphoma and early MRD in Burkitt leukemia is implicated by single studies with risk-adapted therapy. MDD and MRD determined by PCR for ALK-fusion transcripts are independent prognostic parameters for patients with ALK-positive anaplastic large cell lymphoma (ALCL). They are introduced in routine clinical practice and used for patient stratification in clinical studies. Early MRD might serve as an endpoint for clinical trials and for guiding individual therapy. Validation of MDD and MRD as prognostic parameters is required for all subtypes but ALCL. Next-generation sequencing-based methods may provide new options and applications for minimal disease evaluation in childhood lymphomas.

Second malignant neoplasms after treatment of non-Hodgkin's lymphoma-a retrospective multinational study of 189 children and adolescents

Data on the spectrum of second malignant neoplasms (SMNs) after primary childhood non-Hodgkin's lymphoma (NHL) are scarce. One-hundred-and-eighty-nine NHL patients diagnosed in a 30 years period of 1980-2010 developing an SMN were retrieved from 19 members of the European Intergroup for Childhood NHL and/or the international Berlin-Frankfurt-Münster Study Group. Five subgroups of SMNs were identified: (1) myeloid neoplasms (n = 43; 23%), (2) lymphoid neoplasms (n = 51; 27%), (3) carcinomas (n = 48; 25%), (4) central nervous system (CNS) tumors (n = 19; 10%), and (5) "other" SMNs (n = 28; 15%). In 37 patients (20%) preexisting disorders were reported with 90% having any kind of cancer predisposition syndrome (CPS). For the 189 primary NHL patients, 5-year overall survival (OS) after diagnosis of an SMN was 56 ± 4%, being worst for patients with preexisting disorders at 28 ± 8%. Five-year OS rates were 38 ± 8%, 59 ± 7%, 79 ± 8%, 34 ± 12%, and 62 ± 11%, respectively, for patients with myeloid and lymphoid neoplasms, carcinomas, CNS tumors, and "other" SMNs (p < 0.0001). Patients with SMNs after childhood NHL having a reported CPS, mostly mismatch repair disorders, carried a very poor prognosis. Moreover, although outcome was favorable in some subtypes of SMNs after childhood NHL (carcinomas, lymphoid neoplasms), other SMNs such as myeloid neoplasms and CNS tumors had a dismal prognosis.

Prognostic value of 18F-FDG PET/CT in T-Lymphoblastic lymphoma before and after hematopoietic stem cell transplantation

PURPOSE

We aimed to evaluate the prognostic value of ¹⁸F-FDG PET/CT in patients with relapsed or refractory T-Lymphoblastic lymphoma (T-LBL) undergoing hematopoietic stem cell transplantation (HSCT).

METHODS

PET/CT was performed in 21 consecutive relapsed or refractory T-LBL patients scheduled for HSCT. All PET/CT images were assessed using the Deauville criteria, and patients were divided into negative (Deauville ≤ 3) and positive (Deauville > 3) groups for comparison. The predictive value of sex, age, Ann Arbor stage, presence of B symptoms, lactate dehydrogenase level, presence of extranodal disease, and PET/CT results before and after HSCT were evaluated.

RESULTS

Kaplan-Meier analysis showed that only PET/CT after HSCT (post-PET) was correlated with progression-free survival (PFS) (P = 0.030). The Cox regression model also showed that the post-PET-positive group had a higher hazard ratio (HR) than the negative group (HR = 3.884 and P = 0.049). However, none of the evaluated factors were predictive of overall survival (OS).

CONCLUSIONS

Pre-PET cannot predict the PFS and OS of patients with T-LBL undergoing HSCT, which means that ¹⁸F-FDG PET/CT cannot be used for identifying patients who can benefit from HSCT. Post-PET is not predictive for OS in patients with T-LBL undergoing HSCT. However, post-PET showed strong correlations with PFS, which means that it may be useful for guiding subsequent clinical treatment decisions.

Effect of SLCO1B1 Polymorphisms on High-Dose Methotrexate Clearance in Children and Young Adults With Leukemia and Lymphoblastic Lymphoma

High-dose (HD) methotrexate (MTX) is a critical component of treatment for hematologic malignancies in children and young adults. Therapeutic drug monitoring is necessary due to substantial interindividual variation in MTX clearance. Common function-altering polymorphisms in SLCO1B1 (encodes OATP1B1, which transports MTX) may contribute to clearance variability. We performed pharmacokinetic modeling using data for 106 children and young adults treated with HD MTX for hematologic malignancies; of 396 total courses of HD MTX, 360 consisted of 5 g/m² over 24 hours. We evaluated the contribution of clinical covariates and SLCO1B1 genotype (388A>G and 521T>C) to MTX clearance variability. Of the clinical covariates studied, patient weight improved the pharmacokinetic model most significantly (P < 0.001). The addition of the SLCO1B1 variants individually further improved the model (P < 0.05 for each). An interaction between these variants was suggested when both were included (P = 0.017). SLCO1B1 genotype should be considered in efforts to personalize HD MTX dosing.