Treatment Options for Paediatric Anaplastic Large Cell Lymphoma (ALCL): Current Standard and beyond. Cancers (Basel). 2018;10. [PMID: 29601554 PMCID: PMC5923354 DOI: 10.3390/cancers10040099]

Programmed Death Ligand 1 (PD-L1) Expression in Lymphomas: State of the Art

The interaction of programmed death-1 (PD-1) on T lymphocytes with its ligands Programmed Death Ligand 1 (PD-L1) and Programmed Death Ligand 2 (PD-L2) on tumor cells and/or tumor-associated macrophages results in inhibitory signals to the T-cell receptor pathway, consequently causing tumor immune escape. PD-L1/PD-L2 are currently used as predictive tissue biomarkers in clinical practice. Virtually PD-L1 levels expressed by tumor cells are associated with a good response to immune checkpoint blockade therapies targeting the PD-1/PD-L1 axis. These therapies restore T-cell antitumor immune response by releasing T-lymphocytes from the inhibitory effects of tumor cells. Immune checkpoint therapies have completely changed the management of patients with solid cancers. This therapeutic strategy is less used in hematological malignancies, although good results have been achieved in some settings, such as refractory/relapsed classic Hodgkin lymphoma and primary mediastinal large B-cell lymphoma. Variable results have been obtained in diffuse large B-cell lymphoma and T-cell lymphomas. Immunohistochemistry represents the main technique for assessing PD-L1 expression on tumor cells. This review aims to describe the current knowledge of PD-L1 expression in various types of lymphomas, focusing on the principal mechanisms underlying PD-L1 overexpression, its prognostic significance and practical issues concerning the evaluation of PD-L1 immunohistochemical results in lymphomas.

Podcast on Emerging Treatment Options for Pediatric Patients with ALK-Positive Anaplastic Large Cell Lymphoma and Inflammatory Myofibroblastic Tumors

Anaplastic large cell lymphoma (ALCL) and inflammatory myofibroblastic tumor (IMT) are rare cancers observed predominantly in children and young adults. ALCL accounts for 10-15% of all pediatric non-Hodgkin lymphomas and is commonly diagnosed at an advanced stage of disease. In children, 84-91% of cases of ALCL harbor an anaplastic lymphoma kinase (ALK) gene translocation. IMT is a rare mesenchymal neoplasm that also tends to occur in children and adolescents. Approximately 50-70% of IMT cases involve rearrangements in the ALK gene. A combination of chemotherapeutic drugs is typically used for children with ALK-positive ALCL, and the only known curative therapy for ALK-positive IMT is complete surgical resection. Crizotinib, a first-generation ALK inhibitor, was approved in the USA in 2021 for pediatric patients and young adults with relapsed or refractory ALK-positive ALCL; however, its safety and efficacy have not been established in older adults. In 2022, crizotinib was approved for adult and pediatric patients with unresectable, recurrent, or refractory ALK-positive IMT. This podcast provides an overview of ALK-positive ALCL and IMT. We discuss the current treatment landscape, the role of ALK tyrosine kinase inhibitors, and areas of future research.

STAT3 couples activated tyrosine kinase signaling to the oncogenic core transcriptional regulatory circuitry of anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is an aggressive, CD30+ T cell lymphoma of children and adults. ALK fusion transcripts or mutations in the JAK-STAT pathway are observed in most ALCL tumors, but the mechanisms underlying tumorigenesis are not fully understood. Here, we show that dysregulated STAT3 in ALCL cooccupies enhancers with master transcription factors BATF3, IRF4, and IKZF1 to form a core regulatory circuit that establishes and maintains the malignant cell state in ALCL. Critical downstream targets of this network in ALCL cells include the protooncogene MYC, which requires active STAT3 to facilitate high levels of MYC transcription. The core autoregulatory transcriptional circuitry activity is reinforced by MYC binding to the enhancer regions associated with STAT3 and each of the core regulatory transcription factors. Thus, activation of STAT3 provides the crucial link between aberrant tyrosine kinase signaling and the core transcriptional machinery that drives tumorigenesis and creates therapeutic vulnerabilities in ALCL.

Malignancy-Associated Secondary Hemophagocytic Lymphohistiocytosis Mimicking an Infection: A Case Report and Review of the Literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hematological disorder of immune dysregulation associated with significant challenges in diagnosis and management. Described as primary HLH secondary to genetic defects or more commonly secondary to infections, it can also occur secondary to malignancy, i.e., malignancy-associated hemophagocytic lymphohistiocytosis (M-HLH). A five-year-old male child presented with left cervical adenopathy and a high-spiking fever for two weeks. He had pallor, anasarca, multiple enlarged and matted cervical lymph nodes, respiratory distress, and hepatomegaly. He had continuous high-grade fever spikes (maximum 105 °F), not touching baseline despite broad-spectrum antibiotics. The CBC revealed anemia with thrombocytopenia. Liver function tests showed mild transaminitis and hypoalbuminemia. The HLH workup showed elevated ferritin, low fibrinogen, and elevated triglycerides. Lymph node biopsy showed intermediate to large atypical monomorphic lymphocyte cells with ALK, CD30, CD5, CD3, CD45, and BCL-2 (weak positive) positivity and Ki-67-95%, suggestive of anaplastic large cell lymphoma (ALCL). The bone marrow aspiration showed reactive marrow with hemophagocytosis. The patient was started on dexamethasone and chemotherapy per the Children's Oncology Group's (COG) ALCL protocol. He showed remarkable clinical improvement and went into remission after the induction phase. Malignancy associated with HLH can mimic infection, as in our patient with high-spiking fever, consolidation, and mediastinal adenopathy. A high index of suspicion is necessary to arrive at an appropriate, early diagnosis, and workup for malignancy is to be considered when an infectious etiology is not identified after thorough evaluation.

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.

ALK-positive anaplastic large cell lymphoma in adults

ALK-positive anaplastic large cell lymphoma (ALCL) represents approximately 6-7% of the mature T-cell lymphomas. This subtype contains a translocation between the ALK gene on chromosome 2 and one of several other genes that together form an oncogene. The most frequent translocation is t(2;5) which combines ALK with NPM1. This lymphoma has a median age of 34 years, is more common in males, and is in advanced stage at the time of diagnosis in most patients. ALK-positive ALCL is the most curable of the peripheral T-cell lymphomas. The CHOP regimen has been most frequently used, but results are improved with the substitution of brentuximab vedotin for vincristine (BV-CHP) and the addition of etoposide (CHOEP), with BV-CHP being favored. Salvage therapies include allogeneic or autologous bone marrow transplantation, BV, if not used as part of the primary therapy, and ALK inhibitors. The latter are very active and likely to be incorporated into the primary therapy.

An update on Alectinib: a first line treatment for ALK-positive advanced lung cancer

INTRODUCTION

Alectinib is a second-generation, anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) for the treatment of ALK+ non-small cell lung cancer (NSCLC) and is able to induce significant and durable CNS responses. However, long-term use of alectinib has been clinically reported to cause some serious and even life-threatening adverse events. There are currently no effective interventions for its adverse events, and this undoubtedly leads to delays in patient treatment and limits its long-term clinical use.

AREAS COVERED

Based on the clinical trials conducted so far, we summarize the efficacy and adverse events that occurred, especially those related to cardiovascular disorders, gastrointestinal disorders, hepatobiliary disorders, musculoskeletal and connective tissue disorders, skin and subcutaneous tissue disorders, and respiratory disorders. The factors that may influence alectinib selection are also described. Findings are based on a PubMed literature search of clinical and basic science research papers spanning 1998-2023.

EXPERT OPINION

The significant prolongation of patient survival compared with first-generation ALK inhibitor suggests its potential as a first-line treatment for the NSCLC, but the severe adverse events of alectinib limit its long-term clinical use. Future research should focus on the exact mechanisms of these toxicities, how to alleviate the adverse events caused by alectinib clinically, and the development of next-generation drugs with reduced toxicities.

Refractory Anaplastic Large Cell Lymphoma Rescued by the Combination of the Second-Generation ALK Inhibitor Brigatinib, High-dose Chemotherapy and Allogeneic Stem Cell Transplantation: A Case Report and Review of the Literature

The treatment of pediatric patients with refractory or relapsed anaplastic large cell lymphoma (ALCL) is still a major challenge. In addition to conventional chemotherapy and stem cell transplantation, new therapeutic options such as anti-CD30 drugs and anaplastic lymphoma kinase (ALK) inhibitors have been recently introduced in this setting. Among ALK inhibitors, only the first-generation molecule crizotinib is approved for pediatric use, while second-generation molecules, such as brigatinib, are still under investigation. Here we report the case of a 13-year-old boy diagnosed with stage IV ALCL, refractory to first-line conventional chemotherapy and second-line therapy with the anti CD30 antibody-drug conjugate brentuximab-vedotin, who finally achieved remission after a combination of conventional high-dose chemotherapy and the second-generation ALK inhibitor brigatinib. The latter was chosen for its ability to penetrate through the blood-brain barrier, due to the persistent involvement of the patient's cerebral nervous system. The remission was then consolidated with an allogeneic hematopoietic stem cell transplantation (HSCT) from an unrelated donor using myeloablative conditioning with total body irradiation. At 24 months after HSCT, the patient is in complete remission, alive and well. An updated review regarding the use of ALK inhibitors in ALCL patients is provided.

Biopathology of childhood, adolescent and young adult non-Hodgkin lymphoma

Mature non-Hodgkin lymphomas (NHL) in the childhood, adolescent and young adult (CAYA) population are rare and exhibit unique clinical, immunophenotypic and genetic characteristics. Application of large-scale unbiased genomic and proteomic technologies such as gene expression profiling and next generation sequencing (NGS) have led to enhanced understanding of the genetic basis for many lymphomas in adults. However, studies to investigate the pathogenetic events in CAYA population are relatively sparse. Enhanced understanding of the pathobiologic mechanisms involved in non-Hodgkin lymphomas in this unique population will allow for improved recognition of these rare lymphomas. Elucidation of the pathobiologic differences between CAYA and adult lymphomas will also lead to the design of more rational and much needed, less toxic therapies for this population. In this review, we summarize recent insights gained from the proceedings of the recent 7th International CAYA NHL Symposium held in New York City, New York October 20-23, 2022.

Soft-Tissue Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma in a Child Unmasked by COVID-19

Anaplastic large cell lymphoma (ALCL) is children's most common mature T-cell neoplasm. The majority is positive for anaplastic lymphoma kinase (ALK). Initial presentation as a soft-tissue pelvic mass without nodal involvement is rare and can be easily misdiagnosed. We report a case of a 12-year-old male presenting with pain and movement restriction in the right extremity. Computed tomography (CT) scan revealed a solitary pelvic mass. Initial biopsy examination concluded rhabdomyosarcoma. After developing pediatric multisystemic inflammatory syndrome due to coronavirus disease 2019 (COVID-19), central and peripheral lymph node enlargement appeared. New cervical adenopathy and pelvic mass biopsies were performed. Immunohistochemistry concluded an ALK-positive ALCL with a small-cell pattern. The patient was treated with brentuximab-based chemotherapy and eventually improved. Differential diagnosis of pelvic masses in children and adolescents must include ALCL. An inflammatory trigger may promote the appearance of a typical nodal disease, previously absent. Attention is warranted during histopathological examination to avoid diagnostic errors.

Genomic profiling for clinical decision making in lymphoid neoplasms

With the introduction of large-scale molecular profiling methods and high-throughput sequencing technologies, the genomic features of most lymphoid neoplasms have been characterized at an unprecedented scale. Although the principles for the classification and diagnosis of these disorders, founded on a multidimensional definition of disease entities, have been consolidated over the past 25 years, novel genomic data have markedly enhanced our understanding of lymphomagenesis and enriched the description of disease entities at the molecular level. Yet, the current diagnosis of lymphoid tumors is largely based on morphological assessment and immunophenotyping, with only few entities being defined by genomic criteria. This paper, which accompanies the International Consensus Classification of mature lymphoid neoplasms, will address how established assays and newly developed technologies for molecular testing already complement clinical diagnoses and provide a novel lens on disease classification. More specifically, their contributions to diagnosis refinement, risk stratification, and therapy prediction will be considered for the main categories of lymphoid neoplasms. The potential of whole-genome sequencing, circulating tumor DNA analyses, single-cell analyses, and epigenetic profiling will be discussed because these will likely become important future tools for implementing precision medicine approaches in clinical decision making for patients with lymphoid malignancies.

PDGFRβ promotes oncogenic progression via STAT3/STAT5 hyperactivation in anaplastic large cell lymphoma

BACKGROUND

Anaplastic large cell lymphoma (ALCL) is an aggressive non-Hodgkin T cell lymphoma commonly driven by NPM-ALK. AP-1 transcription factors, cJUN and JUNb, act as downstream effectors of NPM-ALK and transcriptionally regulate PDGFRβ. Blocking PDGFRβ kinase activity with imatinib effectively reduces tumor burden and prolongs survival, although the downstream molecular mechanisms remain elusive.

METHODS AND RESULTS

In a transgenic mouse model that mimics PDGFRβ-driven human ALCL in vivo, we identify PDGFRβ as a driver of aggressive tumor growth. Mechanistically, PDGFRβ induces the pro-survival factor Bcl-xL and the growth-enhancing cytokine IL-10 via STAT5 activation. CRISPR/Cas9 deletion of both STAT5 gene products, STAT5A and STAT5B, results in the significant impairment of cell viability compared to deletion of STAT5A, STAT5B or STAT3 alone. Moreover, combined blockade of STAT3/5 activity with a selective SH2 domain inhibitor, AC-4-130, effectively obstructs tumor development in vivo.

CONCLUSIONS

We therefore propose PDGFRβ as a novel biomarker and introduce PDGFRβ-STAT3/5 signaling as an important axis in aggressive ALCL. Furthermore, we suggest that inhibition of PDGFRβ or STAT3/5 improve existing therapies for both previously untreated and relapsed/refractory ALK+ ALCL 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.

Quantitative Acetylomics Uncover Acetylation-Mediated Pathway Changes Following Histone Deacetylase Inhibition in Anaplastic Large Cell Lymphoma

Histone deacetylases (HDACs) target acetylated lysine residues in histone and non-histone proteins. HDACs are implicated in the regulation of genomic stability, cell cycle, cell death and differentiation and thus critically involved in tumorigenesis. Further, HDACs regulate T-cell development and HDAC inhibitors (HDACis) have been approved for clinical use in some T-cell malignancies. Still, the exact targets and mechanisms of HDAC inhibition in cancer are understudied. We isolated tumor cell lines from a transgenic mouse model of anaplastic large cell lymphoma (ALCL), a rare T-cell lymphoma, and abrogated HDAC activity by treatment with the HDACis Vorinostat and Entinostat or Cre-mediated deletion of Hdac1. Changes in overall protein expression as well as histone and protein acetylation were measured following Hdac1 deletion or pharmacological inhibition using label-free liquid chromatography mass spectrometry (LC-MS/MS). We found changes in overall protein abundance and increased acetylation of histones and non-histone proteins, many of which were newly discovered and associated with major metabolic and DNA damage pathways. For non-histone acetylation, we mapped a total of 1204 acetylated peptides corresponding to 603 proteins, including chromatin modifying proteins and transcription factors. Hyperacetylated proteins were involved in processes such as transcription, RNA metabolism and DNA damage repair (DDR). The DDR pathway was majorly affected by hyperacetylation following HDAC inhibition. This included acetylation of H2AX, PARP1 and previously unrecognized acetylation sites in TP53BP1. Our data provide a comprehensive view of the targets of HDAC inhibition in malignant T cells with general applicability and could have translational impact for the treatment of ALCL with HDACis alone or in combination therapies.

FDA approval summary: Crizotinib for pediatric and young adult patients with relapsed or refractory systemic anaplastic large cell lymphoma

In January 2021, the U.S. Food and Drug Administration (FDA) approved crizotinib for pediatric patients 1 year and older and young adults with relapsed or refractory systemic anaplastic large cell lymphoma (sALCL). This is the first approval for pediatric sALCL. Approval was based on a single-arm trial of crizotinib monotherapy that included 26 patients, aged 1-20 years, with previously treated sALCL. Efficacy was based on centrally assessed objective response rate (88%) and duration of response. Herein, we highlight unique aspects of the regulatory review, including extension of the indication to young adults, postmarketing safety, and dose optimization strategies.

Atlas of PD-L1 for Pathologists: Indications, Scores, Diagnostic Platforms and Reporting Systems

Background. Innovative drugs targeting the PD1/PD-L1 axis have opened promising scenarios in modern cancer therapy. Plenty of assays and scoring systems have been developed for the evaluation of PD-L1 immunohistochemical expression, so far considered the most reliable therapeutic predictive marker. Methods. By gathering the opinion of acknowledged experts in dedicated fields of pathology, we sought to update the currently available evidence on PD-L1 assessment in various types of tumors. Results. Robust data were progressively collected for several anatomic districts and leading international agencies to approve specific protocols: among these, TPS with 22C3, SP142 and SP263 clones in lung cancer; IC with SP142 antibody in breast, lung and urothelial tumors; and CPS with 22C3/SP263 assays in head and neck and urothelial carcinomas. On the other hand, for other malignancies, such as gastroenteric neoplasms, immunotherapy has been only recently introduced, often for particular histotypes, so specific guidelines are still lacking. Conclusions. PD-L1 immunohistochemical scoring is currently the basis for allowing many cancer patients to receive properly targeted therapies. While protocols supported by proven data are already available for many tumors, dedicated studies and clinical trials focusing on harmonization of the topic in other still only partially explored fields are surely yet advisable.

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.

The New Treatment Methods for Non-Hodgkin Lymphoma in Pediatric Patients

One of the most common cancer malignancies is non-Hodgkin lymphoma, whose incidence is nearly 3% of all 36 cancers combined. It is the fourth highest cancer occurrence in children and accounts for 7% of cancers in patients under 20 years of age. Today, the survivability of individuals diagnosed with non-Hodgkin lymphoma varies by about 70%. Chemotherapy, radiation, stem cell transplantation, and immunotherapy have been the main methods of treatment, which have improved outcomes for many oncological patients. However, there is still the need for creation of novel medications for those who are treatment resistant. Additionally, more effective drugs are necessary. This review gathers the latest findings on non-Hodgkin lymphoma treatment options for pediatric patients. Attention will be focused on the most prominent therapies such as monoclonal antibodies, antibody–drug conjugates, chimeric antigen receptor T cell therapy and others.

Genetic profiling and biomarkers in peripheral T-cell lymphomas: current role in the diagnostic work-up

Peripheral T-cell lymphomas are a heterogeneous, and usually aggressive, group of mature T-cell neoplasms with overlapping clinical, morphologic and immunologic features. A large subset of these neoplasms remains unclassifiable with current diagnostic methods ("not otherwise specified"). Genetic profiling and other molecular tools have emerged as widely applied and transformative technologies for discerning the biology of lymphomas and other hematopoietic neoplasms. Although the application of these technologies to peripheral T-cell lymphomas has lagged behind B-cell lymphomas and other cancers, molecular profiling has provided novel prognostic and diagnostic markers as well as an opportunity to understand the biologic mechanisms involved in the pathogenesis of these neoplasms. Some biomarkers are more prevalent in specific T-cell lymphoma subsets and are being used currently in the diagnosis and/or risk stratification of patients with peripheral T-cell lymphomas. Other biomarkers, while promising, need to be validated in larger clinical studies. In this review, we present a summary of our current understanding of the molecular profiles of the major types of peripheral T-cell lymphoma. We particularly focus on the use of biomarkers, including those that can be detected by conventional immunohistochemical studies and those that contribute to the diagnosis, classification, or risk stratification of these neoplasms.

ALK-positive anaplastic large T-cell lymphoma presenting primarily as a sinonasal mass with pseudoproptosis: A case report

We report a case of anaplastic lymphoma kinase-positive anaplastic large T-cell lymphoma (ALK+ALCL) presenting primarily as a sinonasal mass with pseudoproptosis in an 11-year-old boy. The diagnosis was based on histopathological and immunohistochemical (IHC) evaluation, which is indispensable for determining tumor type. On the basis of clinicoradiological findings, provisional differential diagnoses of angiofibroma and rhabdomyosarcoma were made. Upon histopathological examination of the biopsy sent, the diagnosis of lymphoma in the sinonasal region was considered. Upon IHC, the tumor cells showed immunoreactivity for vimentin, CD45, CD30, and ALK. The tumor cells showed focal immunoreactivity for CD3 and CD68. Ki-67 labeling index was 70%. They were nonimmunoreactive for PAN cytokeratin, epithelial membrane antigen, cluster of differentiation (CD) 20, CD15, CD56, S100, smooth muscle actin, and myogenin. The diagnosis of ALK+ALCL was rendered. The studied IHC markers confirmed the histopathological diagnosis and helped in further subtyping. To the best of our knowledge, this is the first case of ALCL presenting primarily as a sinonasal mass with pseudoproptosis.

Resistance to Targeted Agents Used to Treat Paediatric ALK-Positive ALCL

Simple Summary

In general, the non-Hodgkin lymphoma (NHL), anaplastic large cell lymphoma (ALCL) diagnosed in childhood has a good survival outcome when treated with multi-agent chemotherapy. However, side effects of treatment are common, and outcomes are poorer after relapse, which occurs in up to 30% of cases. New drugs are required that are more effective and have fewer side effects. Targeted therapies are potential solutions to these problems, however, the development of resistance may limit their impact. This review summarises the potential resistance mechanisms to these targeted therapies.

Abstract

Non-Hodgkin lymphoma (NHL) is the third most common malignancy diagnosed in children. The vast majority of paediatric NHL are either Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), anaplastic large cell lymphoma (ALCL), or lymphoblastic lymphoma (LL). Multi-agent chemotherapy is used to treat all of these types of NHL, and survival is over 90% but the chemotherapy regimens are intensive, and outcomes are generally poor if relapse occurs. Therefore, targeted therapies are of interest as potential solutions to these problems. However, the major problem with all targeted agents is the development of resistance. Mechanisms of resistance are not well understood, but increased knowledge will facilitate optimal management strategies through improving our understanding of when to select each targeted agent, and when a combinatorial approach may be helpful. This review summarises currently available knowledge regarding resistance to targeted therapies used in paediatric anaplastic lymphoma kinase (ALK)-positive ALCL. Specifically, we outline where gaps in knowledge exist, and further investigation is required in order to find a solution to the clinical problem of drug resistance in ALCL.

New Advances in Liquid Biopsy Technologies for Anaplastic Lymphoma Kinase (ALK)-Positive Cancer

Cancer cells are characterized by high genetic instability, that favors tumor relapse. The identification of the genetic causes of relapse can direct next-line therapeutic choices. As tumor tissue rebiopsy at disease progression is not always feasible, noninvasive alternative methods are being explored. Liquid biopsy is emerging as a non-invasive, easy and repeatable tool to identify specific molecular alterations and monitor disease response during treatment. The dynamic follow-up provided by this analysis can provide useful predictive information and allow prompt therapeutic actions, tailored to the genetic profile of the recurring disease, several months before radiographic relapse. Oncogenic fusion genes are particularly suited for this type of analysis. Anaplastic Lymphoma Kinase (ALK) is the dominant driver oncogene in several tumors, including Anaplastic Large-Cell Lymphoma (ALCL), Non-Small Cell Lung Cancer (NSCLC) and others. Here we review recent findings in liquid biopsy technologies, including ctDNA, CTCs, exosomes, and other markers that can be investigated from plasma samples, in ALK-positive cancers.

The Challenges of Crizotinib Treatment in a Child With Anaplastic Large Cell Lymphoma

Survival in cases involving childhood malignancy is reaching nearly 80% in high-income countries, yet cancer remains one of the leading disease-related causes of death in children. In adult oncology the role of targeted therapies is established, but information regarding the use of these therapies in children is limited, largely because targeted therapies were developed in the context of adult pathologies. The few pediatric reports regarding crizotinib, an anaplastic lymphoma kinase (ALK) inhibitor, seem promising. This case of an 8-year-old male with an ALK-positive anaplastic large cell lymphoma highlights the challenges of treating children with crizotinib. Our experience with crizotinib was more challenging than described in the limited pediatric reports. Not only was the tumor response poorer than described in the reports, but a substantial amount of side-effects and practical difficulties, such as the method of administration and dosing, made management challenging. Many challenges for the use of targeted therapy in pediatric care currently persist. The limited research in pediatric populations leaves uncertainty regarding efficacy and short- and long-term side effects as well as practical difficulties. Despite a clear underlying biological rationale for certain targeted therapies, their contribution toward improving the outcome of childhood cancer remains largely unclear.

Update on Pediatric and Young Adult Mature Lymphomas

After acute leukemia and brain and central nervous system tumors, mature lymphomas represent the third most common cancer in pediatric patients. Non-Hodgkin lymphoma accounts for approximately 60% of lymphoma diagnoses in children, with the remainder representing Hodgkin lymphoma. Among non-Hodgkin lymphomas in pediatric patients, aggressive lymphomas, such as Burkitt lymphoma, diffuse large B-cell lymphoma, and anaplastic large cell lymphoma, predominate. This article summarizes the epidemiologic, histopathologic, and molecular features of selected mature systemic B-cell and T-cell lymphomas encountered in this age group.

Rapidly progressing primary pulmonary lymphoma masquerading as lung infectious disease: A case report and review of the literature

BACKGROUND

Primary anaplastic large cell lymphoma of the lung represents a diagnostic challenge due to diverse manifestations and non-specific radiological findings, particularly in cases that lack extra-pulmonary manifestations and lung biopsy.

CASE SUMMARY

A 40-year-old woman presented with a 6-d history of fever, dry coughing, and dyspnea. Her white blood cell count was 20100/mm3 with 90% neutrophils. PaO2 was 60 mmHg and SaO2 was 90% when breathing ambient air. Chest computed tomography (CT) identified a solid nodule, 15 mm in diameter, with a poorly defined boundary in the upper right lung, and several smaller solid nodules throughout both lungs. Pulmonary artery CT and subsequent bedside X-ray showed diffuse patchy shadows throughout both lungs. Repeated cultures of blood samples and alveolar lavage failed to identify any pathogen. Due to the mismatch between clinical and imaging features, we conducted a bone marrow biopsy, and the results showed proliferation along all three lineages but no atypical or malignant cells. The patient received empirical antibacterial, antiviral, and antifungal treatments, as well as corticosteroids. The patient's condition deteriorated rapidly despite treatment. The patient died 6 d after hospitalization due to respiratory failure. Post-mortem lung biopsy failed to show inflammation but identified widespread infiltration of alveolar septum by anaplastic lymphoma kinase (ALK)-positive anaplastic cells.

CONCLUSION

ALK-positive anaplastic large cell lymphoma could present as a primary pulmonary disease without extra-pulmonary manifestations.

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.

IL10RA modulates crizotinib sensitivity in NPM1-ALK+ anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.

Brentuximab vedotin in combination with chemotherapy for pediatric patients with ALK+ ALCL: results of COG trial ANHL12P1

The addition of brentuximab vedotin was tolerable and prevented relapses, and EFS compares favorably with conventional chemotherapy.

The study confirmed that minimal disseminated disease detection in peripheral blood was prognostic, with a significant impact on EFS.

Approximately 30% of pediatric patients with anaplastic large cell lymphoma (ALCL) relapse. Although brentuximab vedotin has demonstrated excellent activity in ALCL, it has not been used for newly diagnosed patients. Children’s Oncology Group (COG) trial ANHL12P1 determined the toxicity and efficacy of brentuximab vedotin with chemotherapy in children with newly diagnosed nonlocalized anaplastic large cell lymphoma kinase (ALK)⁺/CD30⁺ ALCL. From 2013 to 2017, 68 children with ALK⁺ ALCL were enrolled and received brentuximab vedotin. All patients received 5-day prophase, followed by 6 cycles of chemotherapy. Brentuximab vedotin was given on day 1 of each of the 6 cycles. Of the 67 patients eligible for toxicity evaluation, 66 completed all 6 cycles of chemotherapy, resulting in 399 evaluable cycles. There were no toxic deaths, no case of progressive multifocal leukoencephalopathy syndrome, and no case of grade 3 or 4 neuropathy. The 2-year event-free survival (EFS) was 79.1% (95% confidence interval [CI], 67.2-87.1). The 2-year overall survival (OS) was 97.0% (95% CI, 88.1-99.2). Fourteen patients relapsed. Eleven of 14 (79%) relapses occurred within 10 months of diagnosis; only 1 patient (1.5%) relapsed during therapy. Quantitative reverse transcription polymerase chain reaction for NPM-ALK at baseline (minimal disseminated disease) demonstrated prognostic value for EFS (P = .0004). Overall, the addition of brentuximab vedotin to standard chemotherapy does not add significant toxicity or alter the desired interval between cycles. The addition of brentuximab vedotin prevented relapses during therapy, and the OS and EFS estimates compare favorably with results obtained using conventional chemotherapy. This trial was registered at www.clinicaltrials.gov as #NCT01979536.

PD-1/PD-L1 Pathway and Its Blockade in Patients with Classic Hodgkin Lymphoma and Non-Hodgkin Large-Cell Lymphomas

PURPOSE OF REVIEW

Programmed cell death protein-1 (PD-1) is currently the most extensively studied inhibitory checkpoint molecule. Many malignant neoplasms express the PD-1 ligands, PD-L1, and/or PD-L2, which bind to PD-1 on T cells and induce T cell "exhaustion." By doing so, the malignant cells escape from an antitumor immune response (immune evasion). Blockade of the PD-1/PD-L1 pathway releases T cells from the inhibitory effects exerted by tumor cells and restores a T cell-mediated antitumor immune response. Here, we focus on understanding the immune biology of the PD-1/PD-L1 pathway in large-cell lymphomas, including classic Hodgkin lymphoma (CHL), diffuse large B cell lymphoma (DLBCL), and anaplastic large-cell lymphoma (ALCL), and the current status of PD-1 blockade immunotherapy in treating patients with these lymphomas.

RECENT FINDINGS

PD-1/PD-L1 pathway and PD-1 inhibitors have been widely tested in patients with a variety of lymphomas. Nivolumab and pembrolizumab have been approved by the U.S. Food and Drug Administration for treating patients with some types of relapsed or refractory (R/R) lymphomas. The highest response rate has been achieved in patients with CHL, due to a high frequency of genetic alterations of 9p24.1 and high expression of PD-1 ligands. The frequency of alterations of chromosome 9p24.1 and expression of PD-L1/PD-L1 in DLBCL (except some specific subtypes) is low; therefore, it is not recommended to treat unselected DLBCL patients with PD-1 inhibitors. Studies have shown a high frequency of PD-L1 expression in ALCL, especially in anaplastic lymphoma kinase (ALK)+ type. Several cases reports have described a dramatic and durable response to PD-1 blockade in patients with R/R ALCL, suggesting that patients with R/R ALCL may be potential candidates for PD-1 blockade immunotherapy. Understanding the immune biology of lymphoid neoplasms has helped us identify the specific lymphoma types that are vulnerable to PD-1 inhibitors, such as CHL, and specific subtypes of DLBCL. However, our knowledge of many other lymphomas, including ALCL, in this area is still very limited and the future of PD-1 inhibitors in treating those lymphomas remains unclear.

B7-H3 Chimeric Antigen Receptor Redirected T Cells Target Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma

Simple Summary

Although chemotherapy is associated with high relapse rates and numerous side effects, it is still used as the front line treatment of anaplastic large cell lymphoma (ALCL). Therefore, alternative treatment options for ALCL are needed. In this study, we show that B7-H3 is a novel and promising target in ALCLs, and demonstrate that B7-H3 directed chimeric antigen receptor (CAR) T cells have therapeutic potency in controlling ALCL tumor growth.

Abstract

Potent CAR-T therapies that target appropriate antigens can benefit the treatment of anaplastic lymphoma kinase-positive (ALK⁺) anaplastic large cell lymphoma (ALCL), which is the most common subtype of T cell lymphoma. In this study, we observed overexpression of B7-H3 in ALCL cell lines derived from clinical samples and differential expression of B7-H3 in an ALK-induced T cell transformation model. A B7-H3-redirected CAR based on scFv from mAb 376.96 was developed. B7-H3 CAR-T cells showed strong cytotoxicity and cytokine secretion against target ALCL cells (SUP-M2, SU-DHL-1, and Karpas 299) in vitro. Furthermore, the B7-H3 CAR-T cells exhibited proliferative capacity and a memory phenotype upon repeated antigen stimulation. We demonstrated that B7-H3 CAR-T cells could promptly eradicate ALCL in murine xenografts. Taken together, B7-H3 is a novel and promising target in ALCLs and B7-H3 CAR-T may be a viable treatment option for ALCL.

Minimal Residual Disease Monitoring Using a 3'ALK Universal Probe Assay in ALK-Positive Anaplastic Large-Cell Lymphoma: ddPCR, an Attractive Alternative Method to Real-Time Quantitative PCR

In ALK-positive anaplastic large-cell lymphomas, positive qualitative PCR for NPM1-anaplastic lymphoma kinase (ALK) in peripheral blood and/or bone marrow at diagnosis and during treatment are associated with a higher risk of treatment failure. Real-time quantitative PCR allows identification of very high risk patients. However, this latter technique initially designed for patients with lymphomas carrying the most frequent NPM1-ALK translocation necessitates calibration curves, limiting interlaboratory reproducibility. An ALK universal quantitative PCR based on 3'ALK transcript amplification was designed to allow the detection of all ALK fusion transcripts. The absolute concordance of 3'ALK quantitative PCR results were validated with the routine NPM1-ALK qualitative and quantitative PCR on 46 samples. The universality of ALK fusion transcript detection also was validated on TPM3-, ALO17-, and ATIC-ALK-positive samples, and the EML4-ALK-positive cell line. Digital droplet PCR using the 3'ALK universal probe showed highly concordant results with 3'ALK universal quantitative PCR. A major benefit of digital droplet PCR is a reduced experimental set-up compared with quantitative PCR, without generation of standard curves, leading to a reliable protocol for multilaboratory validation in multicenter clinical trials essential for this rare pathology. Our ALK universal method could be used for the screening of ALK fusion transcripts in liquid biopsy specimens of other ALK-positive tumors, including non-small cell lung carcinomas.

Combination of crizotinib and chemotherapy in patients with relapsed or refractory anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL)

Our aim was to explore the role of crizotinib, targeted anaplastic lymphoma kinase (ALK), on r/r systemic anaplastic large cell lymphoma (sALCL). The treated group prospectively screened 20 patients. After taking crizotinib in the first week, 16 patients who were tolerant and sensitive received the combination of crizotinib with chemotherapy. The control group included 27 patients receiving chemotherapy in the same hospital during the same period. The objective remission rates of the treated and control group were 81.3% and 74.1% (p = .869), respectively. The progression-free survival rates at two years in treated and control group were 68.7% and 45.0% (HR = 0.42, 95% CI 0.17-0.99, p < .05), respectively. The overall survival rates at two years in the treated and control group were 86.1% and 78.9% (p = .385, HR = 0.51, 95% CI 0.11-2.30), respectively. The main adverse events included elevated transaminase, diarrhea, and vision abnormalities. Thus, the combination of crizotinib with chemotherapy might be effective in ALK-positive and crizotinib sensitive r/r sALCL patients.

The novel ALK inhibitor ZX-29 induces apoptosis through inhibiting ALK and inducing ROS-mediated endoplasmic reticulum stress in Karpas299 cells

It is a well-known fact that 60%-85% of anaplastic large cell lymphoma (ALCL) is mainly driven by the anaplastic lymphoma kinase (ALK) fusion protein. Although ALK-positive ALCL patients respond significantly to ALK inhibitors, the development of resistance is inevitable, which requires the development of new therapeutic strategies for ALK-positive ALCL. Here, we investigated the anticancer activities of N-(2((5-chloro-2-((2-methoxy-6-(4-methylpiperazin-1-yl)pyridin-3yl)amino)pyrimidin-4-yl)amino)phenyl)methanesulfonamide (ZX-29), a newly synthesized ALK inhibitor, against nucleophosmin-ALK-positive cell line Karpas299. We demonstrated that ZX-29 decreased Karpas299 cells growth and had better cytotoxicity than ceritinib, which was mediated through downregulating the expression of ALK and related proteins, inducing cell cycle arrest, and promoting cell apoptosis. Moreover, ZX-29-induced cell apoptosis by inducing endoplasmic reticulum stress (ERS). In addition, ZX-29 increased the generation of reactive oxygen species (ROS), and cells pretreatment with N-acetyl- l-cysteine could attenuate ZX-29-induced cell apoptosis and ERS. Taken together, ZX-29 inhibited Karpas299 cell proliferation and induced apoptosis through inhibiting ALK and its downstream protein expression and inducing ROS-mediated ERS. Therefore, our results provide evidence for a novel antitumor candidate for the further investigation.

High Levels of miR-7-5p Potentiate Crizotinib-Induced Cytokilling and Autophagic Flux by Targeting RAF1 in NPM-ALK Positive Lymphoma Cells

Simple Summary

Anaplastic lymphoma kinase positive anaplastic large cell lymphomas are a pediatric disease, which still needs treatment improvement. Crizotinib was the first ALK-targeted inhibitor used in clinics, but relapses are now known to occur. Current research efforts indicate that combined therapies could represent a superior strategy to eradicate malignant cells and prevent tumor recurrence. Autophagy is a self-digestion cellular process, known to be induced upon diverse cancer therapies. Our present work demonstrates that the potentiation of the crizotinib-induced autophagy flux, through the serine/threonine kinase RAF1 downregulation, drives ALK+ ALCL cells to death. These results should encourage further investigations on the therapeutic modulation of autophagy in this particular cancer settings and other ALK-related malignancies.

Abstract

Anaplastic lymphoma kinase positive anaplastic large cell lymphomas (ALK+ ALCL) are an aggressive pediatric disease. The therapeutic options comprise chemotherapy, which is efficient in approximately 70% of patients, and targeted therapies, such as crizotinib (an ALK tyrosine kinase inhibitor (TKI)), used in refractory/relapsed cases. Research efforts have also converged toward the development of combined therapies to improve treatment. In this context, we studied whether autophagy could be modulated to improve crizotinib therapy. Autophagy is a vesicular recycling pathway, known to be associated with either cell survival or cell death depending on the cancer and therapy. We previously demonstrated that crizotinib induced cytoprotective autophagy in ALK+ lymphoma cells and that its further intensification was associated with cell death. In line with these results, we show here that combined ALK and Rapidly Accelerated Fibrosarcoma 1 (RAF1) inhibition, using pharmacological (vemurafenib) or molecular (small interfering RNA targeting RAF1 (siRAF1) or microRNA-7-5p (miR-7-5p) mimics) strategies, also triggered autophagy and potentiated the toxicity of TKI. Mechanistically, we found that this combined therapy resulted in the decrease of the inhibitory phosphorylation on Unc-51-like kinase-1 (ULK1) (a key protein in autophagy initiation), which may account for the enforced autophagy and cytokilling effect. Altogether, our results support the development of ALK and RAF1 combined inhibition as a new therapeutic approach in ALK+ ALCL.

A rare case of constrictive pericarditis as initial manifestation of paediatric anaplastic large cell lymphoma requiring urgent pericardiectomy

Constrictive pericarditis (CP) is a rare end stage inflammatory disorder affecting both parietal and visceral pericardium leading to a right heart failure. Malignancy is the least common cause of CP. Anaplastic large cell lymphoma (ALCL) accounts for 10-15% of all Non-Hodgkin lymphomas in children. Very few case reports have reported ALCL that is involving the heart and only two have been published involving pericardium but all were managed medically. We present an interesting case of an 11 year old child who presented with an effusive CP that required urgent Pericardiectomy for managing right heart failure. His histopathology was positive for ALK + ALCL.

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.

Elimination of dormant, autophagic ovarian cancer cells and xenografts through enhanced sensitivity to anaplastic lymphoma kinase inhibition

BACKGROUND

Poor outcomes for patients with ovarian cancer relate to dormant, drug-resistant cancer cells that survive after primary surgery and chemotherapy. Ovarian cancer (OvCa) cells persist in poorly vascularized scars on the peritoneal surface and depend on autophagy to survive nutrient deprivation. The authors have sought drugs that target autophagic cancer cells selectively to eliminate residual disease.

METHODS

By using unbiased small-interfering RNA (siRNA) screens, the authors observed that knockdown of anaplastic lymphoma kinase (ALK) reduced the survival of autophagic OvCa cells. Small-molecule ALK inhibitors were evaluated for their selective toxicity against autophagic OvCa cell lines and xenografts. Autophagy was induced by reexpression of GTP-binding protein Di-Ras3 (DIRAS3) or serum starvation and was evaluated with Western blot analysis, fluorescence imaging, and transmission electron microscopy. Signaling pathways required for crizotinib-induced apoptosis of autophagic cells were explored with flow cytometric analysis, Western blot analysis, short-hairpin RNA knockdown of autophagic proteins, and small-molecule inhibitors of STAT3 and BCL-2.

RESULTS

Induction of autophagy by reexpression of DIRAS3 or serum starvation in multiple OvCa cell lines significantly reduced the 50% inhibitory concentration of crizotinib and other ALK inhibitors. In 2 human OvCa xenograft models, the DIRAS3-expressing tumors treated with crizotinib had significantly decreased tumor burden and long-term survival in 67% to 79% of mice. Crizotinib treatment of autophagic cancer cells further enhanced autophagy and induced autophagy-mediated apoptosis by decreasing phosphorylated STAT3 and BCL-2 signaling.

CONCLUSIONS

Crizotinib may eliminate dormant, autophagic, drug-resistant OvCa cells that remain after conventional cytoreductive surgery and combination chemotherapy. A clinical trial of ALK inhibitors as maintenance therapy after second-look operations should be seriously considered.

PD-L1 expression is associated with ALK positivity and STAT3 activation, but not outcome in patients with systemic anaplastic large cell lymphoma

The programmed cell death 1 (PD-1) pathway is a recently recognized mechanism of tumor immune evasion. In this study, programmed cell death ligand 1 (PD-L1) expression was evaluated in 95 patients with systemic anaplastic large cell lymphoma: 45 ALK+ and 50 ALK-. ALK+ anaplastic large cell lymphoma was more often positive for PD-L1 than ALK- anaplastic large cell lymphoma (76% vs 42%, p = 0.002). ALK- anaplastic large cell lymphoma showed a strong correlation between PD-L1 expression and STAT3 activation (measured by pSTAT3^Tyr705) (r = 0.8, p < 0.0001). In contrast, the PD-L1/pSTAT3 correlation was weaker in ALK+ anaplastic large cell lymphoma (r = 0.4, p = 0.08). In ALK- anaplastic large cell lymphoma, the PD-L1+ subgroup was more often EMA positive (69% vs 20%, p = 0.02) and tended to be less often CD2+ (50% vs 83%, p = 0.059). In ALK+ anaplastic large cell lymphoma, PD-L1 was not associated with pathologic features (all p > 0.05). Negative ALK status and high IPI score (≥3) were associated with shorter overall survival (p = 0.009 and p = 0.0005, respectively). Overall survival was not different between patients with PD-L1+ vs PD-L1- anaplastic large cell lymphoma (p = 0.44), regardless of ALK status and International Prognostic Index (IPI) score. We conclude that PD-L1 expression is more common in ALK+ anaplastic large cell lymphoma than ALK- anaplastic large cell lymphoma. In ALK- anaplastic large cell lymphoma, PD-L1 is strongly correlated with STAT3 activation and is associated with more frequent EMA and less frequent CD2 expression. PD-L1 has no prognostic significance in predicting the outcome of patients with systemic anaplastic large cell lymphoma, regardless of ALK status. PD-L1 expression on the anaplastic large cell lymphoma cells suggests these patients as potential candidates for PD-1 blockade immunotherapy.

18F-FDG PET/CT imaging findings in anaplastic large cell lymphoma, a rare subtype of lymphoma

OBJECTIVE

To investigate the 18F-FDG PET/CT imaging manifestations for anaplastic large cell lymphoma (ALCL), a rare subtype of T/NK cell lymphoma.

METHODS

Fifty patients with ALCL, including 32 anaplastic lymphoma kinase (ALK)-positive patients and 18 ALK-negative patients, were enrolled. The positive detection, maximal standardized uptake value (SUVmax), and distribution of nodal and extranodal involvement were recorded and analysed. Fifty patients with diffuse large B cell lymphoma (DLBCL) were collected as a control group.

RESULTS

ALCL lesions were demonstrated to be 18F-FDG-avid tumours with a mean SUVmax of 19.4 ± 12.6. Most (76%) ALCL patients presented with stage III-IV disease, and nodal and extranodal involvement occurred in 74.0 and 72.0% of the patients, respectively. ALCL and DLBCL showed many similarities in tumour stage, 18F-FDG uptake and tumour involvement (P > 0.05), although the preferred extranodal organs of involvement (bone and the gastrointestinal tract, respectively) were different (P < 0.05). Compared to ALK-negative lesions, a higher uptake of 18F-FDG was found in the ALK-positive lesions (SUVmax: 22.1 ± 14.3 vs. 15.1 ± 6.6, t = 2.354, P = 0.023). ALK-positive ALCL was more likely to involve the lymph nodes than ALK-negative ALCL (84.3% vs. 55.5%, χ2 = 4.973, P = 0.043), while ALK-negative ALCL was more prone to involve the extranodal organs compared to ALK-positive ALCL (88.9% vs. 62.5%, χ2 = 3.979, P = 0.046).

CONCLUSION

The present study demonstrated that ALCL is a systemic 18F-FDG-avid lymphoma with many imaging manifestations similar to DLBCL on PET/CT. The present study also showed that ALK expression actually influenced tumour 18F-FDG uptake and lesion distribution. These findings may be useful to improve the understanding of the biological characteristics of ALCL.

Pathology and genetics of anaplastic large cell lymphoma

Anaplastic large cell lymphomas are a rare subtype of peripheral/mature T-cell lymphomas which are clinically, pathologically and genetically heterogeneous. Both ALK-positive (ALK+) and ALK-negative (ALK-) ALCL are composed of large lymphoid cells with abundant cytoplasm and pleomorphic features with horseshoe-shaped and reniform nuclei. ALK+ ALCL were considered as a definite entity in the 2008 World Health Organization classification of hematopoietic and lymphoid tissues. ALK-ALCL was included as a provisional entity in the WHO 2008 edition and in the most recent 2017 edition, it is now considered a distinct entity that includes cytogenetic subsets that appear to have prognostic implications (e.g. 6p25 rearrangements at IRF4/DUSP22 locus). ALK+ ALCLs are distinct in epidemiology and pathogenetic origin and should be distinguished from ALK-ALCL, cutaneous ALCL and breast implant associated ALCL which have distinct clinical course and pathogenetic features. Breast implant-associated ALCL is now recognized as a new provisional entity distinct from other ALK-ALCL; notably that it is a noninvasive disease associated with excellent outcome. In this article, we will provide an overview of the salient themes relevant to the pathology and genetic mechanisms in ALCL.

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.

The targetable kinase PIM1 drives ALK inhibitor resistance in high-risk neuroblastoma independent of MYCN status

Resistance to anaplastic lymphoma kinase (ALK)-targeted therapy in ALK-positive non-small cell lung cancer has been reported, with the majority of acquired resistance mechanisms relying on bypass signaling. To proactively identify resistance mechanisms in ALK-positive neuroblastoma (NB), we herein employ genome-wide CRISPR activation screens of NB cell lines treated with brigatinib or ceritinib, identifying PIM1 as a putative resistance gene, whose high expression is associated with high-risk disease and poor survival. Knockdown of PIM1 sensitizes cells of differing MYCN status to ALK inhibitors, and in patient-derived xenografts of high-risk NB harboring ALK mutations, the combination of the ALK inhibitor ceritinib and PIM1 inhibitor AZD1208 shows significantly enhanced anti-tumor efficacy relative to single agents. These data confirm that PIM1 overexpression decreases sensitivity to ALK inhibitors in NB, and suggests that combined front-line inhibition of ALK and PIM1 is a viable strategy for the treatment of ALK-positive NB independent of MYCN status.

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.

The Transcriptional Roles of ALK Fusion Proteins in Tumorigenesis

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase involved in neuronal and gut development. Initially discovered in T cell lymphoma, ALK is frequently affected in diverse cancers by oncogenic translocations. These translocations involve different fusion partners that facilitate multimerisation and autophosphorylation of ALK, resulting in a constitutively active tyrosine kinase with oncogenic potential. ALK fusion proteins are involved in diverse cellular signalling pathways, such as Ras/extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K)/Akt and Janus protein tyrosine kinase (JAK)/STAT. Furthermore, ALK is implicated in epigenetic regulation, including DNA methylation and miRNA expression, and an interaction with nuclear proteins has been described. Through these mechanisms, ALK fusion proteins enable a transcriptional programme that drives the pathogenesis of a range of ALK-related malignancies.

T-cell therapies for T-cell lymphoma

T-cell lymphomas represent a subpopulation of non-Hodgkin lymphomas with poor outcomes when treated with conventional chemotherapy. A variety of novel agents have been introduced as new treatment strategies either as first-line treatment or in conjunction with chemotherapy. Immunotherapy has been demonstrated to be a promising area for new therapeutics, including monoclonal antibodies and adoptive cellular therapeutics. T-cell therapeutics have been shown to have significant success in the treatment of B-cell malignancies and are rapidly expanding as potential treatment options for other cancers including T-cell lymphomas. Although treating T-cell lymphomas with T-cell therapeutics has unique challenges, multiple targets are currently being studied both preclinically and in clinical trials.

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.