A population-based study of pediatric anaplastic large cell lymphoma

Anaplastic Large-cell Lymphoma in Children: State of the Art in 2023

Anaplastic large-cell lymphoma is a rare disease and account for approximately 10% to 15% of pediatric non-Hodgkin lymphomas. They are characterized by extended stages, a high frequency of B signs and extra nodal involvement. Multiagent chemotherapy cures ∽60% to 75% of patients and relapse occurs in 35% of cases. For relapsed patients, various treatments ranging from vinblastine monotherapy to therapeutic intensification with hematopoietic stem cell transplantation have been evaluated, but there is currently no consensus on the optimal therapeutic strategy. New therapeutic perspectives are being evaluated for relapses and refractory forms as well as high-risk forms including monoclonal antibodies (Anti CD30), ALK inhibitors, and CART cells.

Aggressive non-Hodgkin lymphoma in the pediatric and young adult population; diagnostic and molecular pearls of wisdom

Mature non-Hodgkin lymphomas (NHLs) of the pediatric and young adults(PYA), including Burkitt lymphoma (BL), diffuse large B cell lymphoma (DLBCL), high-grade B cell lymphoma (HGBCL), primary mediastinal large B cell lymphoma (PMBL) and anaplastic large cell lymphoma (ALCL), generally have excellent prognosis compared to the adult population. BL, DLBCL and HGBCL are usually of germinal center (GCB) origin in the PYA population. PMBL neither belongs to the GCB nor the activated B cell subtype and is associated with a poorer outcome than BL or DLBCL of comparable stage. Anaplastic large cell lymphoma is the most frequent peripheral T cell lymphoma occurring in the PYA and accounts for 10-15% of childhood NHL. Most pediatric ALCL, unlike in the adult, demonstrate expression of anaplastic lymphoma kinase (ALK). In recent years, the understanding of the biology and molecular features of these aggressive lymphomas has increased tremendously. This has led to reclassification of newer PYA entities including Burkitt-like lymphoma with 11q aberration. In this review, we will discuss the current progress discovered in frequently encountered aggressive NHLs in the PYA, highlighting the clinical, pathologic and molecular features that aid in the diagnosis of these aggressive lymphomas. We will be updating the new concepts and terminologies used in the new classification systems.

Patient-derived xenograft models of ALK+ ALCL reveal preclinical promise for therapy with brigatinib

Anaplastic large-cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by the oncogenic anaplastic lymphoma kinase (ALK), accounting for approximately 15% of all paediatric non-Hodgkin lymphoma. Patients with central nervous system (CNS) relapse are particularly difficult to treat with a 3-year overall survival of 49% and a median survival of 23.5 months. The second-generation ALK inhibitor brigatinib shows superior penetration of the blood-brain barrier unlike the first-generation drug crizotinib and has shown promising results in ALK+ non-small-cell lung cancer. However, the benefits of brigatinib in treating aggressive paediatric ALK+ ALCL are largely unknown. We established a patient-derived xenograft (PDX) resource from ALK+ ALCL patients at or before CNS relapse serving as models to facilitate the development of future therapies. We show in vivo that brigatinib is effective in inducing the remission of PDX models of crizotinib-resistant (ALK C1156Y, TP53 loss) ALCL and furthermore that it is superior to crizotinib as a second-line approach to the treatment of a standard chemotherapy relapsed/refractory ALCL PDX pointing to brigatinib as a future therapeutic option.

Brentuximab vedotin use in pediatric anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is the most common type of mature T-cell non-Hodgkin lymphoma in children/adolescents. ALCL is characterized by expression of CD30 in the neoplastic lymphoid cells with frequent expression of anaplastic lymphoma kinase (ALK), especially within the pediatric population. Despite multiple efforts to optimize the use of conventional chemotherapy, outcomes in children, adolescents, and adults with ALCL remain suboptimal. Thus, there is a need to improve survival for those with high-risk disease and decrease therapy exposures and toxicities for those with low-risk disease. Targeted therapies, such as the anti-CD30 antibody-drug conjugate, brentuximab vedotin, are new important therapeutic options. Phase I and II studies in adults with relapsed/refractory CD30⁺ lymphomas, including ALCL, demonstrated the safety and efficacy of brentuximab vedotin, leading to FDA approval for relapsed/refractory ALCL in adults and successful incorporation into frontline therapies. Clinical trials in the pediatric population demonstrated similar results in those with relapsed/refractory ALCL. Incorporation of brentuximab vedotin into upfront therapy for children and adolescents with ALCL showed that this novel combination therapy has clinical advantages in comparison to conventional agents alone. Brentuximab vedotin is well-tolerated in both the pediatric and adult populations, even when used in combination with conventional agents. Brentuximab vedotin is an ideal agent to treat ALCL with excellent targeted activity and limited toxicity. Future studies are needed to identify how brentuximab vedotin should be utilized when combined with immunotherapy or other targeted agents (e.g., ALK inhibitors) in both the upfront and relapsed/refractory setting.

Diagnosis and management of ALK-positive anaplastic large cell lymphoma in children and adolescents

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) is a CD30-positive T cell lymphoma characterized by signalling from constitutively activated ALK fusion proteins. Most children and adolescents present in advanced stages, often with extranodal disease and B symptoms. The current front-line therapy standard of six cycles polychemotherapy reaches an event-free survival of 70%. The strongest independent prognostic factors are minimal disseminated disease and early minimal residual disease. At relapse, ALK-inhibitors, Brentuximab Vedotin, Vinblastine, or second line chemotherapy are effective re-inductions. Survival at relapse exceeds 60-70% with consolidation according to the time of relapse (Vinblastine monotherapy or allogeneic hematopoietic stem cell transplantation) so that the overall survival reaches 95%. It needs to be shown whether check-point inhibitors or long-term ALK-inhibition may substitute for transplantation. The future necessitates international cooperative trials testing whether a shift of paradigm to a chemotherapy-free regimen can cure ALK-positive ALCL.

A 15-Year-Old Boy with Primary Maxillary Bone Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma Relapsed with Rib Metastasis after Spontaneous Remission of a Maxillary Bone Lesion: A Case Report and Literature Review

Anaplastic large cell lymphoma (ALCL) is a rare form of non-Hodgkin's lymphoma (NHL) in children, accounting for 10-15% of all NHL cases. ALCL is currently classified as follows: systemic anaplastic lymphoma kinase (ALK)-positive, systemic ALK-negative, primary cutaneous, and breast implant-associated ALCL. In children, systemic ALK-positive ALCL is the most common, and patients often present with extranodal involvement. We report a rare case of systemic ALK-positive ALCL with primary bone involvement in a 15-year-old male patient. Primary bone lymphoma is most commonly observed in diffuse large B-cell lymphoma and is extremely rare in systemic ALCL. Therefore, the clinical features and prognosis of primary bone ALCL remain unclear. Our patient had spontaneous remission of primary maxillary bone ALCL after gingival scraping but relapsed 12 months later with rib metastasis. Spontaneous remission of ALCL has been reported frequently in primary cutaneous ALCL and rarely in systemic ALCL. Our case demonstrates for the first time that systemic ALCL can also present as solitary bone involvement that can spontaneously remit. Because systemic ALCL is aggressive and has a risk of relapse, as in our case, it is important to consider ALCL in the differential diagnosis of primary bone lesions and to make a precise pathological diagnosis.

Treatment of Relapsed and Refractory ALK-Positive Anaplastic Large Cell Lymphoma With ALK-Specific Tyrosine Kinase Inhibitor in Children: A Case Series

Relapsed and refractory ALK-positive anaplastic large cell lymphoma (ALCL) has a poor prognosis. In this report, we present 3 relapsed/refractory pediatric ALCL patients, 1 of these with central nervous system involvement. All 3 patients were treated with ALK inhibitor and achieved complete response. Both crizotinib and alectinib have shown significant activity in pediatric patients with refractory ALK-positive ALCL.

Whole Exome Sequencing reveals NOTCH1 mutations in anaplastic large cell lymphoma and points to Notch both as a key pathway and a potential therapeutic target

Patients diagnosed with Anaplastic Large Cell Lymphoma (ALCL) are still treated with toxic multi-agent chemotherapy and as many as 25-50% of patients relapse. To understand disease pathology and to uncover novel targets for therapy, Whole-Exome Sequencing (WES) of Anaplastic Lymphoma Kinase (ALK)+ ALCL was performed as well as Gene-Set Enrichment Analysis. This revealed that the T-cell receptor (TCR) and Notch pathways were the most enriched in mutations. In particular, variant T349P of NOTCH1, which confers a growth advantage to cells in which it is expressed, was detected in 12% of ALK+ and ALK- ALCL patient samples. Furthermore, we demonstrate that NPM-ALK promotes NOTCH1 expression through binding of STAT3 upstream of NOTCH1. Moreover, inhibition of NOTCH1 with γ-secretase inhibitors (GSIs) or silencing by shRNA leads to apoptosis; co-treatment in vitro with the ALK inhibitor Crizotinib led to additive/synergistic anti-tumour activity suggesting this may be an appropriate combination therapy for future use in the circumvention of ALK inhibitor resistance. Indeed, Crizotinib-resistant and sensitive ALCL were equally sensitive to GSIs. In conclusion, we show a variant in the extracellular domain of NOTCH1 that provides a growth advantage to cells and confirm the suitability of the Notch pathway as a second-line druggable target in ALK+ ALCL.

Living-donor liver transplantation providing an adequate chemotherapy for a pediatric patient with anaplastic large cell lymphoma complicated with liver failure due to the aggravation of biliary hepatopathy by secondary hemophagocytic lymphohistiocytosis

Anaplastic large cell lymphoma (ALCL) accounts for 10-15% of childhood non-Hodgkin lymphoma cases; it is generally chemo-sensitive and is one of the most curable pediatric cancers. We report here a case of pediatric ALCL complicated with acute liver failure due to the aggravation of pre-existing biliary hepatopathy by lymphoma-associated hemophagocytic lymphohistiocytosis (HLH). Although the initial treatment response against ALCL was very good, poor and irreversible liver function due to biliary cirrhosis worsening by lymphoma-associated HLH prevented the patient from receiving further consolidation chemotherapies. To make matters worse, his condition was accompanied with intrahepatic fungal pseudoaneurysm and invasive fungal infection. Thus, we decided to perform an urgent living-donor liver transplantation from his father to correct the patient's liver function and make it possible to proceed with further ALCL therapy. After the living-donor liver transplantation, the patient successfully received consolidation therapy with brentuximab vedotin. To our knowledge, this may be an early reported case of a pediatric patient undergoing liver transplantation during treatment for ALCL. In most patients with HLH-associated ALCL, liver function improves when ALCL is controlled. However, acute liver failure is occasionally observed in HLH cases with pre-existing liver dysfunction. In such cases, liver transplantation should be considered to correct liver dysfunctions if the disease control of HLH is satisfactory.

A Case of Congenital Anaplastic Large Cell Lymphoma in a Very Preterm Low-Birth Weight Neonate

A premature infant male was born at 30 weeks' gestation with severe coagulopathy and thrombocytopenia. Over the first days of his life, the patient developed evidence of immune hyperactivation with adenopathy, hepatosplenomegaly, and elevated ferritin. Although the patient met diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH), flow cytometric based assays were not consistent with primary HLH. A lymph node and bone marrow biopsy eventually revealed the presence of anaplastic lymphoma kinase+anaplastic large cell lymphoma. To our knowledge, this is the earliest presentation of a lymphoma, and expands the known timeframe of lymphomagenesis.

Pediatric mediastinal ALK- negative anaplastic large cell lymphoma (Hodgkin-like pattern) in a 13-year-old girl: a case report and review of literature

Anaplastic large-cell Lymphoma (ALCL) is a rare type of non-Hodgkin lymphoma that is characterized by an entity of large neoplastic cells labeled by the Ki-1 antibody. It constitutes ~2% of all lymphoid neoplasms and is divided into two main categories: anaplastic large-cell kinase (ALK)+ALCL and ALK-ALCL that is recognized by the absence of ALK expression and mostly affects men at older ages. Thus, in this report we present a rare case of ALK-negative ALCL (ALK-ALCL) that was described and diagnosed in a 13-year-old girl in the mediastinum. Highlighting the rarity of manifestation at younger ages and the importance of using immunohistochemical staining in the differential diagnosis of this lymphoid neoplasm.

Favorable outcomes and reduced toxicity with a novel vinblastine-based non-high dose methotrexate (HDMTX) regimen (modified MCP-842) in pediatric anaplastic large cell lymphoma (ALCL): experience from India

Anaplastic large cell lymphoma (ALCL) is a rare form of non-Hodgkin lymphoma (NHL) in children. Most treatment regimens include high-dose methotrexate (HDMTX), which is logistically difficult to administer in resource-limited settings. We evaluated the outcomes of pediatric ALCL patients treated on a uniform protocol (Modified Multicentric Protocol, MCP-842 regimen) at our hospital between January 2005 and December 2016. Of the 68 patients who received treatment on the Modified MCP842 protocol, 46 patients are alive in remission, 11(16%) had disease progression, 9(13%) relapsed after achieving remission, and 5(7%) had treatment-related mortality (TRM). Seventeen of 20 relapsed/progressed patients subsequently expired. With a median follow-up of 55 months (range 2-165 months), the 4-year event-free survival (EFS) and overall survival (OS) are 63% (95% CI of 50-73%) and 70%(95% CI of 57-79%), respectively. An indigenous protocol using vinblastine (without HDMTX and steroids) is feasible in a resource-limited setting and achieves outcomes comparable to regimens incorporating HDMTX, with lower toxicity.

Prognostic Factors and Treatment Outcome of Pediatric Anaplastic Large Cell Lymphoma Treated at the Children Cancer Hospital Egypt

INTRODUCTION

The aim of the current study is to report the epidemiologic data, response rate, treatment outcome, and overall survival of anaplastic large cell lymphoma (ALCL) patients during the 8-year period.

PATIENTS AND METHODS

A retrospective study included all patients with newly diagnosed ALCL from July 2007 till December 2015.

RESULTS

A total of 48 patients were enrolled. The majority (66.7%) were male individuals. Twenty-one patients (43.7%) were low stage I or II, whereas 27 (56.2%) had advanced stage III or IV. Two patients (4.2%) died during induction chemotherapy. Disease status at last follow-up showed 35 patients (72.9%) in complete remission, 5 (10.5%) relapse, and 5 disease progression. The median time to relapse was 17.2 months. Four patients (8.4%) were salvaged by high-dose chemotherapy ifosphamide, carboplatine, etoposide followed by autologous hematopoietic stem cell transplantation, whereas 5 (10.5%) died out of disease progression. The 5-year overall survival and event-free survival were 81.2% and 68.6%, respectively. Median FU period was 58.7 month. Multivariate analysis included age, sex, stage, and response to chemotherapy and showed no statistical significance.

CONCLUSION

Treatment of ALCL according to the Children's Oncology Group ANHL 0131 protocol is well tolerated. The relapsing patient could be salvaged by high-dose chemotherapy and autologous hematopoietic stem cell transplantation.

Novel targeted therapeutic agents for the treatment of childhood, adolescent and young adult non-Hodgkin lymphoma

Non-Hodgkin lymphomas (NHLs) are a heterogeneous group of malignancies. Most NHLs in children, adolescent and young adult patients are aggressive lymphomas that are generally treated with multi-agent chemotherapy or immunochemotherapy regimens. While overall survival is high, the treatment can lead to a high rate of acute and long-term toxicity. However, in the rarer instance of relapsed or refractory disease, outcomes are dismal. Novel therapeutic approaches to the treatment of both T-cell and B-cell NHLs are critical to improve outcomes while also minimising the associated toxicity of current treatment regimes. Potential therapeutic approaches in development include humoral and cellular immunotherapies, small molecule inhibitors of relevant signalling pathways and epigenetic modifying agents. In this review, we will highlight the current state of development of agents of interest with a focus on agents relevant to childhood, adolescent and young adult NHL.

From bench to bedside: the past, present and future of therapy for systemic paediatric ALCL, ALK

Anaplastic large cell lymphoma (ALCL) is a T cell Non-Hodgkin Lymphoma that mainly presents in paediatric and young adult patients. The majority of cases express a chimeric fusion protein resulting in hyperactivation of anaplastic lymphoma kinase (ALK) as the consequence of a chromosomal translocation. Rarer cases lack expression of ALK fusion proteins and are categorised as ALCL, ALK-. An adapted regimen of an historic chemotherapy backbone is still used to this day, yielding overall survival (OS) of over 90% but with event-free survival (EFS) at an unacceptable 70%, improving little over the past 30 years. It is clear that continued adaption of current therapies will probably not improve these statistics and, for progress to be made, integration of biology with the design and implementation of future clinical trials is required. Indeed, advances in our understanding of the biology of ALCL are outstripping our ability to clinically translate them; laboratory-based research has highlighted a plethora of potential therapeutic targets but, with high survival rates combined with a scarcity of funding and patients to implement paediatric trials of novel agents, progress is slow. However, advances must be made to reduce the side-effects of intensive chemotherapy regimens whilst maintaining, if not improving, OS and EFS.

Treatment Options for Paediatric Anaplastic Large Cell Lymphoma (ALCL): Current Standard and beyond

Anaplastic Lymphoma Kinase (ALK)-positive Anaplastic Large Cell Lymphoma (ALCL), remains one of the most curable cancers in the paediatric setting; multi-agent chemotherapy cures approximately 65–90% of patients. Over the last two decades, major efforts have focused on improving the survival rate by intensification of combination chemotherapy regimens and employing stem cell transplantation for chemotherapy-resistant patients. More recently, several new and ‘renewed’ agents have offered the opportunity for a change in the paradigm for the management of both chemo-sensitive and chemo-resistant forms of ALCL. The development of ALK inhibitors following the identification of the EML4-ALK fusion gene in Non-Small Cell Lung Cancer (NSCLC) has opened new possibilities for ALK-positive ALCL. The uniform expression of CD30 on the cell surface of ALCL has given the opportunity for anti-CD30 antibody therapy. The re-evaluation of vinblastine, which has shown remarkable activity as a single agent even in the face of relapsed disease, has led to the consideration of a revised approach to frontline therapy. The advent of immune therapies such as checkpoint inhibition has provided another option for the treatment of ALCL. In fact, the number of potential new agents now presents a real challenge to the clinical community that must prioritise those thought to offer the most promise for the future. In this review, we will focus on the current status of paediatric ALCL therapy, explore how new and ‘renewed’ agents are re-shaping the therapeutic landscape for ALCL, and identify the strategies being employed in the next generation of clinical trials.

Value of 18F-FDG PET and PET/CT for evaluation of pediatric malignancies

Successful management of solid tumors in children requires imaging tests for accurate disease detection, characterization, and treatment monitoring. Technologic developments aim toward the creation of integrated imaging approaches that provide a comprehensive diagnosis with a single visit. These integrated diagnostic tests not only are convenient for young patients but also save direct and indirect health-care costs by streamlining procedures, minimizing hospitalizations, and minimizing lost school or work time for children and their parents. (18)F-FDG PET/CT is a highly sensitive and specific imaging modality for whole-body evaluation of pediatric malignancies. However, recent concerns about ionizing radiation exposure have led to a search for alternative imaging methods, such as whole-body MR imaging and PET/MR. As we develop new approaches for tumor staging, it is important to understand current benchmarks. This review article will synthesize the current literature on (18)F-FDG PET/CT for tumor staging in children, summarizing questions that have been solved and providing an outlook on unsolved avenues.

Infant anaplastic large cell lymphoma with hemophagocytic syndrome

Anaplastic large cell lymphoma (ALCL), anaplastic lymphoma kinase (ALK)-positive, is uncommon in infancy. We present an unusual occurrence of infant ALCL, ALK-positive, associated with hemophagocytic syndrome. To the best of our knowledge, there have been no cases of infant ALCL, ALK-positive, described that have been associated with hemophagocytic syndrome. Particularly in this age group, primary hemophagocytic syndrome is also a consideration, which raises particular differential diagnostic considerations.

Successful treatment with daclizumab of refractory anaplastic lymphoma

Anaplastic large cell lymphoma (ALCL) is a relatively rare and highly malignant form of non-Hodgkin lymphoma (NHL) which accounts for 10-15% of these childhood lymphomas. Current treatment protocols for ALCL in children consist of a short course of high intensity polychemotherapy. Here we describe an 8-year-old female with relapsed ALCL who achieved good response with anti-CD25 monoclonal antibody daclizumab. Daclizumab appears to offer a safe treatment option, but further research needs to be conducted in order to define its role in children with ALCL who do not respond to intensive chemotherapy.

Analysis of human T-cell lymphotropic virus in CD25+ anaplastic large cell lymphoma in children

Anaplastic large cell lymphoma (ALCL) is recognized as 2 distinct diseases: anaplastic lymphoma kinase (ALK)+ ALCL and ALK- ALCL. ALK+ ALCL occurs in younger patients and has a better prognosis. Human T-cell lymphotropic virus (HTLV-1) is linked to the development of adult T-cell leukemia/lymphoma (ATLL), which frequently expresses CD25. CD25 is significantly expressed in childhood ALCL. In Brazil, HTLV-1 infection is endemic, and vertical transmission is responsible for spread to children. Of HTLV-1 carriers, 90% or more remain asymptomatic. Some cases of adult HTLV-1-related lymphomas have characteristics of ALCL but are considered CD30+ ATLL subtypes. No similar cases have been described in children. We analyzed 33 cases of pediatric ALCL, CD25+ and CD25-, for proviral HTLV-1 DNA. All cases corresponded to the common histologic ALCL type and were CD30+ in virtually all neoplastic cells. ALK expression was observed in 31 (94%) of 33 cases; CD25 was positive in 27 (82%), including 1 ALK- ALCL case. There was a strong positive correlation between ALK and CD25 expression. None of the cases showed proviral HTLV-1 DNA. ALCL in children has no relationship with HTLV-1; the frequent CD25 expression must be explained by a mechanism different from that in ATLL.

Imaging of pediatric lymphomas

Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) represent 10% to 15% of all malignancies occurring in children younger than 20 years of age. Advances in cross-sectional imaging and the availability of positron emission tomography (PET) and PET-CT have had a major impact on imaging and management of pediatric patients. This article reviews the clinical features of lymphoma, focusing on the spectrum of imaging findings seen in diagnosis, staging, and follow-up of HL and NHL. Pediatric NHL has four major histologic subtypes: Burkitt lymphoma, diffuse large B-cell lymphoma, anaplastic large cell lymphoma, and lymphoblastic lymphoma. The most important subtype of HL is nodular sclerosis.

Long-term remission of children with relapsed and secondary anaplastic large cell non-Hodgkin lymphoma (ALCL) following treatment with pulsed dexamethasone and low dose etoposide

Anaplastic large cell lymphoma (ALCL) accounts for approximately 15% of childhood NHL. Relapsed ALCL represents a formidable challenge because outcome is poor despite the use of high-dose chemotherapy regimens. We report two patients with relapsed T-type and 0-type ALCL who achieved long-term 3rd and 4th remissions with 4-weekly oral dexamethasone (DEX) and etoposide pulses for 2 years. This regimen also induced and maintained remission in a third patient with Nijmegen breakage syndrome (NBS) with secondary T-type ALCL. These patients demonstrate that low-intensity oral chemotherapy can induce long-term remissions and offer a curative perspective in refractory, relapsed and secondary ALCL.

Infant anaplastic lymphoma: case report and review of the literature

Anaplastic large cell lymphoma (ALCL) is a well-known entity, but there are no data on prognosis according to the age of the patient, especially in infants. A 2-month-old girl was admitted with a 2-week history of coughing, fever, and lymphadenopathy. Physical examination revealed mild respiratory distress, an erythematous macular rash on her trunk, massive cervical lymphadenopathy, splenomegaly, and very mild ascites. Chest radiograph showed bilateral pulmonary infiltrates, pleural effusion, and a mediastinal mass. CBC count showed WBC: 172,000/microL (PMN 40%, lymphocytes 47%, monocytes 3%); hemoglobin concentration: 8.7 g/dL; platelets: 390,000/microL. Cervical lymph node biopsy revealed anaplastic lymphoma with positive staining to ALK 1 and TIA 1. Immunophenotypic analysis of peripheral and bone marrow lymphoid cells showed an aberrant T-cell immunophenotype, including expression of CD3, CD45R0+, CD43+, and CD30+. Cytogenetic analysis performed on blood and bone marrow samples demonstrated the translocation t(2;5) (p23;q35), and trisomy 47. After leucophoresis, the child received chemotherapy according to the ALCL-99-EICNHL protocol, and was started on corticosteroids and cyclophosphamide, which resulted in marked improvement. After the second course, WBC decreased to 6000/microL without tumor lysis syndrome, but the child developed bacterial and fungal disseminated infections and died of septic shock with multiorgan failure. This report is of a rare case of infant anaplastic lymphoma and excellent response to treatment. Unfortunately, she did succumb to overwhelming infection. More reports of similar cases may determine the cause and prognosis of such children, helping to tailor therapy according to the age of the child and other prognostic factors, especially bone marrow involvement.

[Pediatric non-Hodgkin lymphomas]

Non Hodgkin lymphoma represent about 5% of childhood cancer. They are the third most common group of cancers in children and adolescents, after cerebral tumours and leukemias. They differ from adult lymphomas as they are all high grade tumours, always diffuse and often associated with extra-nodal diseases. Three main histological subtypes predominate: Burkitt, lymphoblastic and anaplastic large cell lymphomas. As the clinical progression is growing fast and treatment different between the 3 subtypes, the diagnosis must be rapidly done and with accuracy.

Anaplastic large cell lymphoma with ALK expression and presence of the t(2;5) translocation in a 5-month-old infant

Anaplastic large cell lymphoma (ALCL) is a well-recognized subtype of non-Hodgkin lymphoma in childhood. Several series report experience with the diagnosis and management of pediatric ALCL, the average age at diagnosis being 8 to 16 years, with a reported range of 1 to 15 years. We present a case of ALCL affecting a 5-month-old infant in whom the diagnosis was confirmed by the nuclear and cytoplasmic immunohistochemical expression of ALK1, in addition to the presence of classical t(2;5)(p23;q35) translocation detected using reverse transcriptase-polymerase chain reaction. This is the youngest case of ALCL thus far reported and hence expands the spectrum of infantile lymphoproliferative disorders.

Pathology review for paediatric non-Hodgkin's lymphoma patients in Japan

A central pathology review system with an immunophenotyping laboratory was established in Japan to support the clinical trial, the Japan Association of Childhood Leukaemia Study (JACLS) NHL-98, for patients with paediatric non-Hodgkin's lymphoma (NHL). Pathology samples from 155 clinically-suspected NHL cases were evaluated centrally initially using the Revised European-American Lymphoma (REAL) classification in a rapid review (within 2 weeks after surgery/biopsy) and then later at the consensus review (once a year). The samples were subsequently re-classified according to the new World Health Organisation (WHO) classification. After the pathology review, 96 (62%) patients were eligible for the study, and 58 of them (60%) had extra-nodal primaries. These NHL cases included B-cell lymphomas (precursor B-cell, 11; Burkitt, 18; diffuse large B-cell, 18; not otherwise specified, 3) and T/Natural Killer (NK)-cell lymphomas (precursor T-cell, 23; anaplastic large cell, 20; others, 3). There was excellent concordance in making the diagnoses (95/96, 99%) and typing (93/96, 97%) of NHL between the rapid and consensus reviews. Five cases, initially diagnosed as diffuse large B-cell lymphoma by the review, were re-classified as Burkitt lymphoma according to the immunocytochemical criteria by the WHO classification. A total of 59 (38%) cases were excluded from the study: they were Hodgkin lymphoma (7), leukaemias (11), reactive lymphoid hyperplasia (20), necrotizing lymphadenitis (7), no consensus diagnosis (1), insufficient materials (2), and others (11). This is the first report of the central pathology review from the paediatric NHL group study in Japan. Because various diseases, either neoplastic or reactive, mimicked NHL, clinically and histopathologically, the central pathology review system was critical and essential for patient enrollment and protocol assignment in our clinical trial. Through the two-step review system, highly reliable data were generated to support this study.

Isolated central nervous system (CNS) relapse in a case of childhood systemic anaplastic large cell lymphoma without initial CNS involvement

Central nervous system (CNS) involvement in cases of anaplastic large cell lymphoma (ALCL) has been described only rarely. The authors describe an 11-year-old girl with ALCL who developed isolated CNS relapse but had no CNS disease at initial diagnosis and had received CNS-prophylactic treatment. The patient achieved a second remission following intensive treatment of the relapse and continues to be in remission at the time of writing. This case serves to emphasize that isolated CNS relapse without detectable initial CNS involvement can arise even after CNS-prophylactic treatment in pediatric ALCL cases.

Anaplastic large cell lymphoma in Japanese children: retrospective analysis of 34 patients diagnosed at the National Research Institute for Child Health and Development

This report presents a retrospective study of 34 Japanese children diagnosed at a single laboratory as having anaplastic large cell lymphoma (ALCL). Most of the pathological features of the Japanese ALCL children observed, such as anaplastic lymphoma kinase protein expression, in addition to most of the clinical characteristics and the outcomes of the patients, are very similar to those reported by European groups. To our knowledge, this is the first report describing the details of the clinicopathological features of Japanese ALCL patients. A further International study, including Japanese patients, might contribute to the establishment of an optimal treatment for paediatric ALCL.