Peripheral T-cell lymphoma in children and adolescents: a single-institution experience

Hematopoietic stem cell transplantation for pediatric patients with non-anaplastic peripheral T-cell lymphoma. An EBMT pediatric diseases working party study

Peripheral T-cell lymphomas (PTCL) other than anaplastic large-cell lymphoma are rare in children, and the role of hematopoietic stem cell transplantation (HSCT) has not been clarified yet. In a retrospective analysis of registry-data of the European Society for Blood and Marrow Transplantation we analyzed 55 patients aged < 18 years who received allogeneic (N = 46) or autologous (N = 9) HSCT for PTCL. Median age at HSCT was 13.9 years; 33 patients (60%) were in first remission, and 6 (19%) in progression at HSCT. Conditioning was myeloablative in 87% of the allogeneic HSCTs and in 27 (58.7%) based on total body irradiation. After allogeneic HSCT the 5-year overall- and progression-free survival was 58.9% (95% CI 42.7-71.9) and 52.6% (95% CI 36.8-66.1), respectively. 5-year relapse incidence was 27.6% (95% CI 15.1-41.6), the non-relapse mortality rate was 19.8% (95% CI 9.7-32.6). Five of the six patients with progression at HSCT died. Seven of nine patients after autologous HSCT were alive and disease-free at last follow-up. Our data suggest a role of allogeneic HSCT in consolidation-treatment of patients with high-risk disease, who reach at least partial remission after primary- or relapse-therapy, whereas patients with therapy-refractory or progressive disease prior to transplantation do not profit from HSCT.

Allogeneic Hematopoietic Stem Cell Transplantation for Mature T/NK-Cell Lymphomas in Children

Mature T/NK-cell lymphomas (MTCLs) are a heterogeneous group of lymphoproliferative disorders, relatively rare in adults and children. Allogeneic hematopoietic stem cell transplantation (HSCT) can be considered in some cases as a consolidation and is the first choice for refractory forms and relapses. We retrospectively analyzed 19 pediatric patients with MTCL who received allogeneic hematopoietic stem cell transplantation from a haploidentical or unrelated donor on the αβ T cell depletion platform. Among the studied patients, cutaneous T-cell lymphoma was diagnosed in 5, hepatosplenic γδT-cell lymphoma in 4, ALK-positive anaplastic large cell lymphoma in 9 patients, and 1 had nasal T/NK cell lymphoma. All patients received myeloablative conditioning based on treosulfan or total body irradiation. Non-relapse mortality was 5%, the cumulative incidence of relapse or progression at 5 years was 27%, 5-year event-free survival was 67%, and 5-year overall survival was 78%. Thus, our data support that allogeneic αβ T-cell-depleted HSCT can provide long-term overall survival of children with high-risk mature T-cell lymphomas.

Management of Peripheral T-Cell Lymphoma in Children and Adolescents Including STAT 3 Mutation Hyper-IgE Syndrome: One Size Does Not Fit All

Peripheral T-cell lymphoma (PTCL) is a rare form of lymphoma in children with limited published data on treatment and lack of a uniformly accepted treatment algorithm. We retrospectively analyzed the data in children up to 18 years of age diagnosed to have PTCL from January 2016 to June 2020. The study included six children with a median age of 10 years, the youngest being a 7-month-old girl. According to the WHO-PTCL classification, three had PTCL-not otherwise specified (NOS), 2 had hepatosplenic TCL, and 1 had subcutaneous panniculitis-like TCL. All children had presented with advanced disease, 4 in St. Jude stage IV, 2 in St. Jude stage III. Three children received CHOEP chemotherapy including cyclophosphamide, doxorubicin, vincristine, prednisone, etoposide, while 1 child received CHOP. Two children received induction as per acute lymphoblastic leukemia followed by Bendamustine. Two patients succumbed to progressive disease, the infant with PTCL-NOS and 1 child with hepatosplenic TCL. Three children were in remission (median follow up of 44 mo). One child with PTCL-NOS Stage IV had an underlying STAT3 mutated hyperimmunoglobulin E syndrome and was in remission 12 months post a matched unrelated donor hematopoietic stem cell transplantation. He had grade 4 skin graft versus host disease and required extracorporeal photopheresis and ibrutinib, to which he had responded. CHOEP chemotherapy is well-tolerated and subcutaneous panniculitis-like TCL has the best prognosis thus far.

Durable Response in Relapsed Adolescent Peripheral T-cell Lymphoma: A Case Report and Review of the Literature

Peripheral T-cell lymphoma (PTCL) is an aggressive tumor, rarely seen in pediatrics or adolescent and young adults (AYAs) so there is no upfront or relapsed standard of care. The authors describe a 16-year-old with PTCL, treated with chemotherapy and autologous stem cell transplant. Upon relapse, he received ifosfamide, carboplatin, etoposide, and radiation with durable remission of 4 years. Data in pediatric/AYA PCTL continue to lack an understanding of the biology and microenvironment, the differences to adult patients, and a lack of adequate therapy. Targeted therapy may improve outcomes for children and AYAs with refractory or relapsed PTCL.

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.

Rare non-Hodgkin lymphoma of childhood and adolescence: A consensus diagnostic and therapeutic approach to pediatric-type follicular lymphoma, marginal zone lymphoma, and nonanaplastic peripheral T-cell lymphoma

Pediatric-type follicular (PTFL), marginal zone (MZL), and peripheral T-cell lymphoma (PTCL) account each for <2% of childhood non-Hodgkin lymphoma. We present clinical and histopathological features of PTFL, MZL, and few subtypes of PTCL and provide treatment recommendations. For localized PTFL and MZL, watchful waiting after complete resection is the therapy of choice. For PTCL, therapy is subtype-dependent and ranges from a block-like anaplastic large cell lymphoma (ALCL)-derived and, alternatively, leukemia-derived therapy in PTCL not otherwise specified and subcutaneous panniculitis-like T-cell lymphoma to a block-like mature B-NHL-derived or, preferentially, ALCL-derived treatment followed by hematopoietic stem cell transplantation in first remission in hepatosplenic and angioimmunoblastic T-cell lymphoma.

Primary Nonanaplastic Peripheral Natural Killer/T-Cell Lymphoma in Pediatric Patients-An Unusual Distribution Pattern of Subtypes

Peripheral NK/T-cell lymphoma (PNKTCL) represents a group of uncommon diagnoses for children in Western countries, and studies have often necessitated multiple institutions to assemble enough cases. We retrospectively analyzed 11 cases of nonanaplastic PNKTCL in children over 19 years at our institution with comparison to several published large multi-institutional studies. Patients included 9 males and 2 females of white (5), Native American (3), and Hispanic (3) background with 6 cases of extranodal NK/T-cell lymphoma, nasal type (EN-NKTL, 54.6%), 3 cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS, 27.2%), and 2 cases of systemic Epstein-Barr virus (EBV)-positive T-cell lymphoma of childhood (18.2%). Compared to the literature, our institution exceeded in frequency of total nonanaplastic PNKTCL (4.8% vs 0.9%-1.6%) with lesser relative incidence of PTCL-NOS (27.2% vs 42.9%-66.7%) and greater relative incidence of EN-NKTL (54.6% of cases vs 12.5%-47.6%), which significantly exceeded the literature's rate for Western institutions (13.5%). Potential influencing factors include population structure approximating those of non-Western countries with high EN-NKTL prevalence and the predisposition for EBV infection in this demography. These data suggest an uneven distribution of nonanaplastic PNKTCL in Western countries, and differential diagnoses may differ depending on practice location and associated patient population.

Hepatosplenic γδ T-cell lymphoma of two adolescents: Case report and retrospective literature review in children, adolescents, and young adults

HSTCL is a highly aggressive malignancy with a poor prognosis. Case series and accounts have reported the use of different chemotherapy regimens with diverse patient outcomes. Most long-term survivors had undergone high-dose chemotherapy with autologous or allogeneic HCT. We describe two pediatric patients with HSTCL who were treated with chemotherapy followed by allogeneic HCT. Both patients are alive and in complete remission 2 and 8 years after therapy. Multiagent chemotherapy followed with allogeneic HCT seems to provide patients who have chemotherapy-sensitive disease a long-term disease-free survival.

Hepatosplenic T-cell lymphoma arising in patients with immunodysregulatory disorders: a study of 7 patients who did not receive tumor necrosis factor-α inhibitor therapy and literature review

Hepatosplenic T-cell lymphoma (HSTCL) is a rare and aggressive extranodal T-cell lymphoma that can arise in patients with underlying immune disorders. Others have suggested that tumor necrosis factor (TNF)-α inhibitor therapy for immune disorders increases the risk of HSTCL. To assess for a potential relationship between HSTCL and the use of TNF-α inhibitors, we searched for patients with HSTCL and underlying immune disorders at our institution. We identified 7 patients with a median age of 38 years. Five patients had Crohn disease, 1 ulcerative colitis, and 1 rheumatoid arthritis. In 6 patients, medication history for the immune disorder was available: 6 patients received 6-mercaptopurine or azathioprine, and 2 patients received steroids; no patients received TNF-α inhibitors. In all 7 patients, the histologic, immunophenotypic, and cytogenetic findings were similar to cases of HSTCL that arise in immunocompetent patients. We reviewed the literature and identified 60 patients with immune disorders who subsequently developed HSTCL. These patients were treated with immunosuppressive drugs in 89%, TNF-α inhibitors in 56%, and both therapies in 54%, and 1 (2%) patient was treated with TNF-α inhibitors only. Our cohort and literature review indicates that TNF-α inhibitor therapy is not essential for the development of HSTCL in patients with immunodysregulatory disorders, and implies that immunosuppressive drugs or other factors (eg, genetic predisposition, chronic antigenic stimulation) may be more critical in the pathogenesis in this context. Although these data are observational, they have implications for the use of TNF-α inhibitors in patients with inflammatory bowel disease and other immunodysregulatory disorders.

Non-anaplastic peripheral T cell lymphoma in children and adolescents-an international review of 143 cases

Peripheral T cell lymphomas (PTCL) are rare in children and adolescents, and data about outcome and treatment results are scarce. The present study is a joint, international, retrospective analysis of 143 reported cases of non-anaplastic PTCL in patients <19 years of age, with a focus on treatment and outcome features. One hundred forty-three patients, between 0.3 and 18.7 years old, diagnosed between 2000 and 2015 were included in the study. PTCL not otherwise specified was the largest subgroup, followed by extranodal NK/T cell lymphoma, hepatosplenic T cell lymphoma (HS TCL), and subcutaneous panniculitis-like T cell lymphoma (SP TCL). Probability of overall survival (pOS) at 5 years for the whole group was 0.56 ± 0.05, and probability of event-free survival was (pEFS) 0.45 ± 0.05. Patients with SP TCL had a good outcome with 5-year pOS of 0.78 ± 0.1 while patients with HS TCL were reported with 5-year pOS of only 0.13 ± 0.12. Twenty-five percent of the patients were reported to have a pre-existing condition, and this group had a dismal outcome with 5-year pOS of 0.29 ± 0.09. The distribution of non-anaplastic PTCL subtypes in pediatric and adolescent patients differs from what is reported in adult patients. Overall outcome depends on the subtype with some doing better than others. Pre-existing conditions are frequent and associated with poor outcomes. There is a clear need for subtype-based treatment recommendations for children and adolescents with PTCL.

Mature T- and NK-cell non-Hodgkin lymphoma in children and young adolescents

Mature T/Natural killer (NK)-cell neoplasms of children and the young adolescent population exhibit higher prevalence in Central and South American and Asian populations and many are associated with Epstein-Barr virus (EBV). They are represented in large part by extranodal T/NK cell lymphomas- nasal-type or extra nasal-type, chronic lymphoproliferative disorders of T/NK cells or chronic active EBV disease, systemic EBV-positive lymphoproliferative disorders of childhood, hydroa vacciniforme-like lymphoma, hepatosplenic T-cell lymphoma and primary cutaneous gamma/delta T-cell lymphoma among others. Many T/NK cell neoplasms in this age group are derived from cells of the innate immune system, in contrast to adults where they are predominantly from the adaptive immune system. The genetic basis of T/NK cell lymphomas in children and young adolescents remains largely unknown. Anthracycline-based regimens and haematopoietic stem cell transplants (allogeneic and autologous) are current treatment modalities, however it is anticipated that novel targeted therapeutic agents will be available in the near future.

Cytotoxic Molecule-positive Epstein-Barr Virus-associated Peripheral T-cell Lymphoma in a 20-Month-old Child: A Case Report and Review of the Literature

Peripheral T-cell lymphoma (PTCL) is rare in children. Expression of cytotoxic molecules (CM) in nodal PTCL has unique clinicopathologic features, including an Epstein-Barr virus (EBV) association. However, CM+, EBV-associated PTCL is extremely rare in the childhood, with only 1 study having been reported to date, including both pediatric and adult patients. We report a case of CM+ PTCL in a 20-month-old boy with left neck lymphadenopathy as well as multiple visceral lesions. A biopsied lymph node was diffusely infiltrated by atypical lymphoid cells with a CD4/CD8, granzyme B+, perforin+, and TIA-1+ phenotype, and EBV positivity by in situ hybridization. Rearrangements of the TCR γ-chain and β-chain genes were demonstrated by polymerase chain reaction. Ancillary genetic studies detected trisomy 2, trisomy 10, a structurally abnormal 6p, and additional copies of the IRF4 gene. Multiple bone marrow biopsies failed to show any evidence of tumor, histiocytic hyperplasia, or hemophagocytosis. This lesion was therefore diagnosed as "CM+, EBV-associated high-grade peripheral T-cell lymphoma." After 5 cycles of chemotherapy, the patient was in remission 8 months following initial diagnosis. To our knowledge, this represents the youngest child with this rare tumor in the published literature, and showing an unusually favorable initial response to therapy.

Primary peripheral T-cell lymphoma, not otherwise specified, of the central nervous system in a child

Primary peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), is a rare disease that infrequently involves the central nervous system (CNS), and it is even rarer in pediatric patients. Here, we report of a 13-year-old male with primary CNS PTCL-NOS who exhibited a malignant clinical course with recurrence after radiochemotherapy followed by bone marrow transplantation; he died 43 months after diagnosis. Pathology revealed the proliferation of cytotoxic T-cells and clonal T-cell receptor gene rearrangements. Although the optimal therapy for PTCL remains controversial, intensive radiochemotherapy may be required for some patients.

Uncommon non-Hodgkin lymphomas of childhood: pathological diagnosis, clinical features and treatment approaches

We provide a review of the pathological and clinical features for uncommon B-cell and T-cell lymphomas of childhood with a specific focus on advances in treatment approaches and outcomes. There is clearly a need for prospective investigation of both the clinical and biological features of the uncommon non-Hodgkin lymphoma subtypes in childhood. These results should lead to more uniform and more effective treatment approaches.

Fully human antagonistic antibodies against CCR4 potently inhibit cell signaling and chemotaxis

BACKGROUND

CC chemokine receptor 4 (CCR4) represents a potentially important target for cancer immunotherapy due to its expression on tumor infiltrating immune cells including regulatory T cells (Tregs) and on tumor cells in several cancer types and its role in metastasis.

METHODOLOGY

Using phage display, human antibody library, affinity maturation and a cell-based antibody selection strategy, the antibody variants against human CCR4 were generated. These antibodies effectively competed with ligand binding, were able to block ligand-induced signaling and cell migration, and demonstrated efficient killing of CCR4-positive tumor cells via ADCC and phagocytosis. In a mouse model of human T-cell lymphoma, significant survival benefit was demonstrated for animals treated with the newly selected anti-CCR4 antibodies.

SIGNIFICANCE

For the first time, successful generation of anti- G-protein coupled chemokine receptor (GPCR) antibodies using human non-immune library and phage display on GPCR-expressing cells was demonstrated. The generated anti-CCR4 antibodies possess a dual mode of action (inhibition of ligand-induced signaling and antibody-directed tumor cell killing). The data demonstrate that the anti-tumor activity in vivo is mediated, at least in part, through Fc-receptor dependent effector mechanisms, such as ADCC and phagocytosis. Anti-CC chemokine receptor 4 antibodies inhibiting receptor signaling have potential as immunomodulatory antibodies for cancer.

NK/T-cell lymphomas in children

In children, T and NK-cell lymphomas are uncommon in Western Countries. While there has been significant experience treating T-cell lymphoblastic lymphoma (T-LBL) and anaplastic large cell lymphoma (ALCL), other subtypes are very rarely encountered and there are no standard approaches to their management. There are many challenges in defining optimal therapy for many of these diseases but recent progress in elucidating their biology has led to new molecular insights and identified interesting targets for novel drug discovery. In this review, we discuss these disorders in children, how they are approached therapeutically and what lies on the horizon with respect to novel treatment approaches.