CD30 expression in peripheral T-cell lymphomas

Nodal Peripheral T-Cell Lymphoma: Therapeutic Challenges and Future Perspectives

Peripheral T-cell lymphomas (PTCLs) present a significant clinical challenge despite recent advances in the development of novel therapeutic agents, guided by a deeper understanding of the pathobiology and the genetic and molecular characteristics underlying this complex and heterogeneous group of aggressive non-Hodgkin lymphomas (NHLs) [...].

The fifth edition of the WHO classification of mature T cell, NK cell and stroma-derived neoplasms

The fifth edition of the WHO Classification of Haematolymphoid Tumors (WHO-HAEM5) introduces significant advancements in the understanding and diagnosis of mature T cell and NK cell, and stroma-derived neoplasms, and incorporates molecular and genetic data/findings accrued over the past years. The classification has been reorganised using a hierarchical system, employed across the fifth edition of the WHO classification of tumours of all organ systems. This review highlights recent developments, evolving concepts, and key updates since the revised fourth edition (WHO-HAEM4R). It enumerates the minimal/essential criteria necessary for diagnosis and classification, constituting not only the importance of clonality analysis in the workup of certain T cell neoplasms and the detection of infectious agents and specific genetic alterations in a subset of entities but also the applicability of these criteria in resource-constrained settings. 'Stroma-derived neoplasms of lymphoid tissues discussed in this review is a new category introduced in HAEM5 that encompasses mesenchymal tumours occurring exclusively in lymph nodes and spleen and mesenchymal dendritic cell neoplasms previously classified as 'histiocytic/dendritic cell neoplasms'.

Development of chimeric Nanobody-Granzyme B functionalized ferritin nanoparticles for precise tumor therapy

T-cell lymphomas (TCLs) are heterogeneous malignancies with limited treatment options and poor outcomes. The efficacy of traditional T-cell therapies, including chimeric antigen receptor (CAR) T cells, is often constrained by immunosuppressive factors and the tumor microenvironment. On the other hand, although direct Granzyme B (GrB) administration can effectively induce tumor cell apoptosis, it lacks universal tumor targeting and efficient cellular entry mechanisms. To address these limitations, we developed a novel nanoparticle-based therapy for the precise targeting of TCL tumor cells and the delivery of GrB. We fused nanobody (Nb) targeting CD30 and CD5 with GrB and coupled them to human ferritin (h-HFn) using the Gv/Sd system, creating a novel therapeutic nanoparticle named BiCD30/5-GF, which specifically targets CD30 and CD5 receptors on TCL tumor cells. The Nb-GrB conjugation enhances tumor targeting, while a Gv/Sd linker coupled to h-HFn further improves cellular transport and targeting. Additionally, the multimerization of GrB enhances its effectiveness. These nanoparticles demonstrated superior binding affinity and cytotoxicity in vitro compared to conventional treatments. In vivo studies on tumor-bearing mice showed significant tumor suppression and prolonged survival following treatment with BiCD30/5-GF nanoparticles. We also extended similar nanoparticle strategies for gastric cancer therapy, targeting FGFR4-expressing tumor cells. Our findings highlight the potential of engineered nanoparticles as effective and targeted therapeutic agents across various tumor types, offering promising prospects for clinical translation in cancer treatment.

Antibody-Drug Conjugates Targeting CD30 in T-Cell Lymphomas: Clinical Progression and Mechanism

CD30 is overexpressed in many T-cell lymphoma (TCL) entities, including subsets of peripheral T-cell lymphomas (PTCL) and cutaneous T-cell lymphomas (CTCL). The antibody-drug conjugate brentuximab vedotin (BV), targeting CD30-positive cells, has been approved for the treatment of relapsed or refractory (R/R) systemic anaplastic large cell lymphoma (sALCL), and primary cutaneous anaplastic large cell lymphoma or mycosis fungoides in patients who have received previous systemic therapy. However, many patients still experience disease progression after BV monotherapy. Extensive efforts have been dedicated to investigating effective combinations of BV. A phase III clinical study demonstrated that the combination of BV with cyclophosphamide, doxorubicin, and prednisone (CHP) is superior to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) for CD30-positive PTCL. This study led to the approval of BV with CHP as the first-line therapy for CD30-positive PTCL (sALCL in Europe). We summarize the encouraging combination applications of BV in this review. Ongoing studies on combination therapies of BV are also listed, highlighting potential directions for the future application of BV. We focus on dissecting the underlying mechanisms of BV, discussing its effects on both tumor cells and the tumor microenvironment. Exploring resistance mechanisms in TCL provide valuable insights for optimizing BV-based therapies in the future.

Aberrant expression in lymphoma, a diagnostic pitfall

One of the major difficulties in practical hematopathology is to accurately assign cell lineage and thus ensure proper classification of lymphomas. The lineage-specific markers of lymphoma are detected by immunohistochemistry or flow cytometry immunophenotypic methods. However, aberrant gain or loss of these markers is occasionally encountered during daily practice, which often creates diagnostic challenges. In addition, lymphoma may aberrantly express non-hematopoietic markers, and vice versa. This review article provides an overview of aberrant gain of expression of lineage-associated antigens in mature lymphoid neoplasms, including recommendations to avoid diagnostic pitfalls and ultimately to reach accurate diagnoses.

Systemic ALK-negative anaplastic large cell lymphoma: Insights into morphologic, immunophenotypic, genetic and molecular characteristics

Anaplastic large cell lymphoma (ALCL) is a mature T-cell neoplasm characterized by large pleomorphic cells, often with horseshoe- or kidney-shaped nuclei and abundant cytoplasm (hallmark cells), and uniformly strong CD30 expression. Based on ALK expression or ALK rearrangement, ALCL is further classified into ALK-positive (ALK+) and ALK-negative types. This review focuses on the clinicopathologic, immunophenotypic, cytogenetic and molecular features of systemic ALK-negative ALCL. These patients are usually older adults who present with advanced stage disease and often a poor prognosis. ALK-negative ALCL is morphologically indistinguishable from the common pattern of ALK+ ALCL, but some cases show non-common morphology, such as "donut cells", Hodgkin-like features. ALK-negative ALCL is often negative for T-cell antigens (so-called "antigen loss") and in some cases can have a "null" immunophenotype and be confused with other hematopoietic and non-hematopoietic neoplasms. Recurrent genetic/molecular alterations have been identified in systemic ALK-negative ALCL, including rearrangements of DUSP22, TP63, JAK2, FRK, MYC, ROS1 and TYK2; mutations of JAK1, STAT3 and MSCE; and aberrant expression of ERBB4. Some of these alterations may have prognostic significance and/or provide potential therapeutic targets. Data support the idea that ALK-negative ALCL with DUSP22 rearrangement is a distinctive variant due to its unique morphologic, immunophenotypic and molecular features. Gene expression profiling data have shown that ALK-negative ALCL has distinctive molecular signatures, different from ALK+ ALCL and other T-cell lymphomas. Better understanding of the morphologic, immunophenotypic, genetic and molecular features of ALK-negative ALCL will help establish the correct diagnosis, guide therapeutic strategies and improve patient outcomes.

Recent Advances in Understanding the Clinical Responses of Brentuximab Vedotin in Lymphoma and the Correlation with CD30 Expression

Brentuximab vedotin (BV) is an antibody-drug conjugate that combines the CD30 monoclonal antibody with the microtubule-disrupting agent, monomethyl auristatin E, which induces apoptosis in the tumor cell upon its release from the conjugate. The safety and efficacy of BV have been assessed in several studies in patients with T- and B-cell lymphomas. This article reviews the currently available data on the distribution of CD30 expression in T- and B-cell lymphomas, as well as the various levels of CD30 positivity cutoff used in the literature. It also analyzes the relationship between CD30 expression levels and the clinical response to BV in clinical trials for both T- and B-cell lymphomas and investigates BV efficacy in patients with low or undetectable levels of CD30 and examines potential mechanisms by which BV exerts its effect on these patients. This review contributes to the growing evidence suggesting that CD30 expression levels do not predict the clinical benefit of BV as the drug demonstrated substantial efficacy in patients across a wide range of CD30 expression levels while suggesting that the antitumor activity was not associated with CD30 expression levels. Furthermore, the potential of BV as a targeted approach along with its mechanism of action is also summarized to explain its key role in the future treatments of lymphomas, especially for CD30-expressing lymphomas.

Antibody-Based Therapies for Peripheral T-Cell Lymphoma

While antibody-based immunotherapeutic strategies have revolutionized the treatment of B-cell lymphomas, progress in T-cell lymphomas has suffered from suboptimal targets, disease heterogeneity, and limited effective treatment options. Nonetheless, recent advances in our understanding of T-cell biology, the identification of novel targets, and the emergence of new therapies provide hope for the future. In this review, we explore four areas of current and evolving antibody-based strategies for the treatment of peripheral T-cell lymphoma (PTCL): monoclonal antibodies (mAbs), bispecific antibodies (BsAs), chimeric antigen receptor T-cell therapy (CAR-T), and antibody-drug conjugates (ADCs). As part of this discussion, we will also include limitations, lessons learned, and potential future directions.

Yttrium-90 anti-CD25 BEAM conditioning for autologous hematopoietic cell transplantation in Peripheral T-cell lymphoma

ABSTRACT

Peripheral T-cell lymphomas (PTCLs) have a poor prognosis with current treatments. High-dose chemotherapy followed by autologous hematopoietic cell transplant (AHCT) is used as a consolidation strategy after achieving clinical remission with first-line therapy, as well as in chemotherapy-sensitive relapse if allogeneic transplant is not an option. CD25 is a targetable protein often highly expressed in PTCLs. In this phase 1 clinical trial, we tested the addition of β-emitting 90yttrium (90Y)-labeled chimeric anti-CD25 basiliximab (aTac) to BEAM (carmustine, etoposide, cytarabine, and melphalan) as conditioning for AHCT for patients with PTCL. Twenty-three AHCT-eligible patients were enrolled, and 20 received therapeutic 90Y-aTac-BEAM AHCT. Radiation doses of 0.4, 0.5, and 0.6 mCi/kg were tested. With no observed dose-limiting toxicities, 0.6 mCi/kg was deemed the recommended phase 2 dose. The most prevalent adverse effect, grade 2 mucositis, was experienced by 80% of patients. As of this report, 6 (30%) of the treated patients had died, 5 due to progressive disease and 1 due to multiple organ failure (median time of death, 17 months [range, 9-21]) after AHCT. Median follow-up was 24 months (range, 9-26) overall and 24 months (range, 13-26) for surviving patients. For patients who received therapeutic 90Y-aTac-BEAM AHCT, the 2-year progression-free and overall survival were 59% (95% confidence interval [CI], 34-77) and 68% (95% CI, 42-84), respectively. 90Y-aTac-BEAM appears to be safe as an AHCT conditioning regimen for PTCL, with no increased toxicity over the toxicities historically seen with BEAM alone in this patient population. This trial was registered at www.ClinicalTrials.gov as #NCT02342782.

In vivo CAR T cell therapy against angioimmunoblastic T cell lymphoma

BACKGROUND

For angioimmunoblastic T cell lymphoma (AITL), a rare cancer, no specific treatments are available and survival outcome is poor. We previously developed a murine model for AITL that mimics closely human disease and allows to evaluate new treatments. As in human AITL, the murine CD4+ follicular helper T (Tfh) cells are drivers of the malignancy. Therefore, chimeric antigen receptor (CAR) T cell therapy might represent a new therapeutic option.

METHODS

To prevent fratricide among CAR T cells when delivering an CD4-specific CAR, we used a lentiviral vector (LV) encoding an anti-CD4 CAR, allowing exclusive entry into CD8 T cells.

RESULTS

These anti-CD4CAR CD8-targeted LVs achieved in murine AITL biopsies high CAR-expression levels in CD8 T cells. Malignant CD4 Tfh cells were eliminated from the mAITL lymphoma, while the CAR + CD8 T cells expanded upon encounter with the CD4 receptor and were shaped into functional cytotoxic cells. Finally, in vivo injection of the CAR + CD8-LVs into our preclinical AITL mouse model carrying lymphomas, significantly prolonged mice survival. Moreover, the in vivo generated functional CAR + CD8 T cells efficiently reduced neoplastic T cell numbers in the mAITL tumors.

CONCLUSION

This is the first description of in vivo generated CAR T cells for therapy of a T cell lymphoma. The strategy described offers a new therapeutic concept for patients suffering from CD4-driven T cell lymphomas.

Brentuximab vedotin plus cyclophosphamide, doxorubicin, etoposide, and prednisone followed by brentuximab vedotin consolidation in CD30-positive peripheral T-cell lymphomas: a multicentre, single-arm, phase 2 study

BACKGROUND

CD30 expression is universal in anaplastic large-cell lymphoma and is expressed in some other peripheral T-cell lymphoma subtypes. Incorporation of brentuximab vedotin into initial therapy for people with CD30-positive peripheral T-cell lymphomas prolonged progression-free survival, but there is room for improvement, especially for people with non-anaplastic large-cell lymphoma subtypes.

METHODS

We conducted a multicentre, international, single-arm, phase 2 trial to evaluate the safety and activity of CHEP-BV (cyclophosphamide, doxorubicin, prednisone, brentuximab vedotin, and etoposide) followed by brentuximab vedotin consolidation in patients with CD30-expressing peripheral T-cell lymphomas across five academic centres in the USA and Canada. Adults aged 18 years or older with newly diagnosed, untreated CD30-positive peripheral T-cell lymphomas, Eastern Cooperative Oncology Group score of 0-2, and adequate organ function were eligible to receive six planned cycles of CHEP-BV (ie, 1·8 mg/kg brentuximab vedotin intravenously on day 1, cyclophosphamide 750 mg/m2 intravenously on day 1, doxorubicin 50 mg/m2 intravenously on day 1, etoposide 100 mg/m2 daily intravenously on days 1-3, and prednisone 100 mg daily orally on days 1-5) with prophylactic G-CSF. Patients who responded to the treatment could receive brentuximab vedotin consolidation for up to ten additional cycles either after autologous haematopoietic stem-cell transplantation (HSCT) or directly after CHEP-BV. The primary endpoints were unacceptable toxicity during a 3-plus-3 safety lead-in in participants who received study treatment and completed the safety evaluation period (to confirm the recommended phase 2 dose of brentuximab vedotin in CHEP-BV) and the complete response rate after CHEP-BV induction therapy in participants who received study treatment and had response evaluation. The study was registered at ClinicalTrials.gov (NCT03113500), and this cohort completed the trial. The trial is ongoing with the enrolment of a new cohort.

FINDINGS

54 patients were screened for eligibility and 48 were eligible for the study. The participants (18 [38%] women and 30 [63%] men; 34 [71%] White, four [8%] Black, five [10%] Asian, ten [21%] Hispanic, and 37 [77%] non-Hispanic people) were recruited and enrolled between Dec 4, 2017, and June 14, 2021, and followed up until Aug 25, 2023, when the database was locked for analysis. 48 participants were evaluable for toxicity, and 47 were evaluable for response (one participant died from COVID-19 before response assessment). During the safety lead-in, one of six participants had an unacceptable toxicity (ie, platelet count <10 000 per mm3 in a participant with extensive bone marrow involvement), and the proposed phase 2 dose of 1·8 mg/kg brentuximab vedotin in CHEP-BV was confirmed. At completion of CHEP-BV, 37 of 47 participants had complete response, yielding a complete response rate of 79% (95% CI 64-89). The most common CHEP-BV-related toxicities of grade 3 or higher were neutropenia (14 [29%] of 48), leukopenia (11 [23%]), anaemia (ten [21%]), febrile neutropenia (ten [21%]), lymphopenia (nine [19%]), and thrombocytopenia (nine [19%]). There were no treatment-related deaths.

INTERPRETATION

In patients with mostly CD30-expressing peripheral T-cell lymphomas other than non-anaplastic large-cell lymphoma, CHEP-BV (with or without autologous HSCT) followed by brentuximab vedotin consolidation was safe and active.

FUNDING

SeaGen, Leukemia and Lymphoma Society, Lymphoma Research Foundation, and the National Cancer Institute of the National Institutes of Health.

Peripheral T-cell lymphoma: From biology to practice to the future

Recent advancements in comprehending peripheral T-cell lymphomas (PTCLs) validate and broaden our perspective, highlighting their diverse nature and the varying molecular mechanisms underlying the entities. Based on a comprehensive accumulated understanding, the PTCLs currently overcome the most challenging features of any disease: rarity, incredible heterogeneity, and a lack of any established standard of care. The treatments deployed in the front-line are extrapolated from regimens developed for other diseases. The recent approval of the three drugs brentuximab vedotin (BV), pralatrexate, and belinostat for patients with relapsed or refractory disease has provided clues about pathophysiology and future directions, though challenges satisfying post-marketing requirements (PMR) for those accelerated approvals have led to one of those drugs being withdrawn and put the other two in jeopardy. Edits of the front-line regimens, often called CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-plus approaches, look more like CHOP-minus strategies, as the toxicity of five-drug regimens often reduces the dose intensity of the added 'novel' drug, nullifying any hope of an advance. The turmoil in the field produced by the aforementioned, coupled with an ever-changing classification, has left the field uncertain about the path forward. Despite these challenges, empiric findings from studies of novel drug approaches, coupled with a logic emerging from studies of PTCL lymphomagenesis, have begun to illuminate, albeit faintly for some, a potential direction. The empiric finding that drugs targeting the discrete components of the PTCL epigenome, coupled with the description of multiple mutations in genes that govern epigenetic biology, offers, at the very least, an opportunity to finally be hypothesis-driven. The most recent recognition that the only combination of drugs shown to markedly improve progression-free survival (PFS) in patients with relapsed disease is one based on dual targeting of different and discrete components of that epigenetic biology has established a possibility that circumnavigating chemotherapy addition studies is both plausible, feasible, and likely the best prospect for a quantum advance in this disease. Herein, we analyze PTCL through a 2025 lens, highlighting and underscoring walls that have impeded progress. We will critically explore all the clues and the panoramic view of PTCL research.

Infectious Complications Following CD30 Chimeric Antigen Receptor T-Cell Therapy in Adults

Infections are increasingly recognized as a common complication of chimeric antigen receptor (CAR) T-cell therapy. The incidence of clinically-defined infection after CD19.CAR T-cell therapy for relapsed/refractory lymphoma ranges from 60-90% in the first year after CAR T-cell therapy and is the most common cause for non-relapse mortality. However, infectious risk after CAR T-cell therapy targeting other malignancies is not well understood. Herein, we report for the first time, infectious complications after CD30.CAR T-cell treatment for patients with Hodgkin's lymphoma and peripheral T-cell lymphoma. Since CD30 is only expressed on a subset of activated T and B-cells, we hypothesized that CD30.CAR T-cell patients would have reduced incidence and severity of infections after infusion compared to CD19.CAR T-cell patients. We retrospectively evaluated all 64 patients who received CD30.CAR T-cells at a single institution between 2016-2021, and assessed infections within one year after cell infusion, comparing these data to a contemporary cohort of 50 patients who received CD19.CAR T-cells at the same institution between 2018-2021. 23 CD30.CAR T-cell patients (36%) and 18 CD19.CAR T-cell patients (36%) developed a microbiologically confirmed infection. Infection severity and bacterial infections were higher in the CD19.CAR T-cell group compared to CD30.CAR T-cell recipients who more commonly had grade 1 respiratory viral infections. Our data reflect expected outcomes for severity and infection type in CD19.CAR T-cell patients and provide a benchmark for comparison with the novel CD30.CAR T-cell product. Although our findings require replication in a larger cohort, they have implications for antimicrobial prophylaxis guidelines after CD30.CAR T-cell therapy.

KEY POINTS

1) The incidence of infections within the first year after CD30.CAR T-cell therapy was equivalent to that following CD19.CAR T-cell therapy2) Viral infections were more common after CD30.CAR T-cell therapy but bacterial infections predominated after CD19.CAR T-cell therapy.

Non-invasive biomarkers of acute rejection in pediatric kidney transplantation: New targets and strategies

Kidney transplantation is the preferred treatment for pediatric end-stage renal disease. However, pediatric recipients face unique challenges due to their prolonged need for kidney function to accommodate growth and development. The continual changes in the immune microenvironment during childhood development and the heightened risk of complications from long-term use of immunosuppressive drugs. The overwhelming majority of children may require more than one kidney transplant in their lifetime. Acute rejection (AR) stands as the primary cause of kidney transplant failure in children. While pathologic biopsy remains the "gold standard" for diagnosing renal rejection, its invasive nature raises concerns regarding potential functional impairment and the psychological impact on children due to repeated procedures. In this review, we outline the current research status of novel biomarkers associated with AR in urine and blood after pediatric kidney transplantation. These biomarkers exhibit superior diagnostic and prognostic performance compared to conventional ones, with the added advantages of being less invasive and highly reproducible for long-term graft monitoring. We also integrate the limitations of these novel biomarkers and propose a refined monitoring model to optimize the management of AR in pediatric kidney transplantation.

Complete hematologic response in a patient with multiple pretreated angioimmunoblastic T-cell lymphoma after belinostat therapy followed by allogeneic stem cell transplantation: A case report

Key Clinical Message

Belinostat therapy followed by hematopoietic stem cell transplantation is a promising salvage strategy for heavily pretreated patients with peripheral T-cell lymphoma.

Abstract

Effective treatments for peripheral T-cell lymphoma in the relapsed and refractory (r/r) setting are limited. However, with the development and approval of innovative therapies, effective therapeutic options are becoming available for this patient population. This case report describes the treatment course of a patient with multiple r/r nodal follicular T-helper cell lymphoma of angioimmunoblastic type. Treatment with the histone deacetylase inhibitor belinostat as bridging, enabled allogeneic stem cell transplantation and resulted in a durable complete hematologic response for at least 21 months post-transplantation.

KLRG1, Another Opportunity for a Breakthrough in MTCL

Outcomes in mature T-cell lymphomas remain poor, with previous attempts at developing mAbs compromised by limited efficacy and significant immunocompromise. Anti-killer cell lectin-like receptor G1 mAbs may have greater selectivity and specificity for malignant T cells and avoid the toxicity concerns with previous agents. See related article by Assatova et al., p. 2514.

Brentuximab Vedotin Retreatment in Patients with Relapsed or Refractory Classical Hodgkin Lymphoma or Peripheral T-Cell Lymphoma: A Retrospective United States Claims Analysis

Brentuximab vedotin (BV) monotherapy (BV-M) and combination (BV-C) therapies are safe and effective for classical Hodgkin lymphoma (cHL) and CD30-expressing peripheral T-cell lymphomas (PTCLs). Although the sample sizes have been small (12-29 patients), in clinical studies, response rates of 53-88% have been reported for BV retreatment in patients with an initial BV response. We evaluated the real-world characteristics and treatment patterns of cHL/PTCL patients who received BV and were retreated in the United States. Symphony Health Patient Claims (11/2013-1/2022) were retrospectively analyzed to identify cHL/PTCL patients treated with BV and retreated with BV-M, BV-C, or non-BV therapy. Patient characteristics were described by retreatment, and predictors of BV-M retreatment were identified. Among the cHL and PTCL patients treated with BV (n = 6442 and 2472, respectively), 13% and 12%, respectively, were retreated with BV; the median times from initial BV to BV-M retreatment were 5 and 7 months, respectively; and the numbers of BV-M retreatment doses were 4 and 5, respectively. Among cHL patients, the predictors of BV-M retreatment were age (18-39 vs. ≥60 years), sex (women vs. men), and previous stem cell transplantation (yes vs. no). Among PTCL patients, the only predictor of BV-M retreatment was systemic anaplastic large-cell lymphoma subtype (yes vs. no). Real-world data support clinical study results suggesting earlier BV treatment be considered, as BV retreatment may be an option.

Peripheral T-cell lymphomas expressing CD30 and CD15 expand the spectrum of anaplastic large cell lymphoma, ALK-negative

Peripheral T-cell lymphomas (PTCL) are morphologically and biologically heterogeneous and a subset expresses CD30, including anaplastic large cell lymphomas (ALCL) and a minority of PTCL, not otherwise specified (PTCL, NOS). ALCL with ALK translocations (ALCL, ALK+) are readily identified by routine diagnostic methods, but differentiating ALCL without ALK translocation (ALCL, ALK-) and PTCL, NOS expressing CD30 (PTCL CD30+) can be challenging. Furthermore, rare PTCL co-express CD30 and CD15 (PTCL CD30+CD15+); some resemble ALCL, ALK- while others resemble classic Hodgkin lymphoma. To explore the relationship between PTCL CD30+CD15+ and ALCL, ALK-, we analysed 19 cases of PTCL with CD30 expression, previously diagnosed as ALCL, ALK- (nine cases) and PTCL CD30+CD15+ (10 cases) for DUSP22/IRF4 rearrangements, coding RNA expression and selected transcriptome analysis using the NanoString nCounter gene expression analysis platform. Unsupervised clustering showed no clear segregation between ALCL, ALK- and PTCL CD30+CD15+. Three cases previously classified as PTCL CD30+CD15+ showed DUSP22/IRF4 rearrangements, favouring a diagnosis of ALCL, ALK-. Our results suggest that cases previously designated PTCL CD30+CD15+, likely fall within the spectrum of ALCL, ALK-; additionally, a subset of ALCL, ALK- with DUSP22/IRF4 rearrangement expresses CD15, consistent with previous reports and expands the immunophenotypic spectrum of this lymphoma subgroup.

CXCR4-targeted Theranostics in Hematooncology: Opportunities and Challenges

C-X-C motif chemokine receptor 4 (CXCR4) is overexpressed in a multitude of cancers, including neoplasms of hematopoietic origin. This feature can be leveraged by a theranostic approach, which provides a read-out of the actual CXCR4 expression in vivo, followed by CXCR4-targeted radioligand therapy (RLT) exerting anti-cancer as well as myeloablative efficacy. In a recent meeting of hematooncology and nuclear medicine specialists, statements on the current clinical practice and future perspectives of this innovative concept were proposed and summarized in this opinion article. Experts concluded that i) CXCR4-directed [68Ga]Ga-PentixaFor PET/CT has the potential to improve imaging for patients with marginal zone lymphoma; ii) CXCR4-targeted RLT exerts anti-lymphoma efficacy and myeloablative effects in patients with advanced, treatment-refractory T-cell lymphomas; iii) prospective trials with CXCR4-based imaging and theranostics are warranted.

Innovations in Antibody-Drug Conjugate (ADC) in the Treatment of Lymphoma

Chemoimmunotherapy and cellular therapy are the mainstay of the treatment of relapsed/refractory (R/R) lymphomas. Development of resistance and commonly encountered toxicities of these treatments limit their role in achieving desired response rates and durable remissions. The Antibody-Drug Conjugate (ADC) is a novel class of targeted therapy that has demonstrated significant efficacy in treating various cancers, including lymphomas. To date, three ADC agents have been approved for different lymphomas, marking a significant advancement in the field. In this article, we aim to review the concept of ADCs and their application in lymphoma treatment, provide an analysis of currently approved agents, and discuss the ongoing advancements of ADC development.

NOT OTHERWISE SPECIFIED T-CELL LYMPHOMA: OUTCOMES OF A SINGLE CENTER STUDY

BACKGROUND

The peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) is the most common subtype of peripheral T-cell lymphoma (PTCL). It constitutes approximately 25% of all PTCLs and accounts for more than 15% of all lymphomas. The results of the first Ukrainian prospective study of patients with PTCL-NOS are presented in the article. The aim of the study was to analyze the morbidity of PTCL patients and the treatment performed, to evaluate overall survival and progression-free survival, and to determine the factors that predict the treatment response.

PATIENTS AND METHODS

An analysis was performed on the data of 31 patients diagnosed with peripheral PTCL-NOS from February 2018 to the present. T-cell lymphoid neoplasms were diagnosed according to the 2016 WHO classification. The treatment regimens were in alignment with ESMO and NCCN guidelines. More than 90% of patients were prescribed anthracycline-based regimens (CHOP; CHOEP - cyclophosphamide, doxorubicin, etoposide, vincristine, prednisone). An initial treatment was performed with CHOP-based regimens in 38.70% (n = 12) of patients, with the addition of etoposide in 58.06% of patients (n = 18).

RESULTS

The response was assessed according to the response criteria for malignant lymphoma (Cheson, 2008, 2014). The overall response to therapy was 58.06% (n = 18), with complete responses in 29.03% of patients and partial responses in 29.03% of patients. The stabilization of the disease occurred in 3.44%, while the disease progression in 41.37% of patients. The 12-month and 24-month survival rates were 75.44% and 50.81%, respectively. The 12-month and 24-month progression-free survivals were 47.68% and 33.1%, respectively. Ki-67 overexpression (> 65%) was a negative prognostic factor.

CONCLUSIONS

The results of the treatment of PTCL obtained in a Ukrainian population study are similar to those in other European studies, all of which remain unsatisfactory. Further research is required to develop a new strategy for examination and therapy to improve treatment outcomes. The emphasis should be placed on the pragmatic clinical trials comparing the efficacy of first-line treatment in PTCL patients with both favorable and unfavorable clinical factors.

SOHO State-of-the-Art Updates and Next Questions: Treatment for Newly Diagnosed Peripheral T-Cell Lymphomas

Although a rare subset of non-Hodgkin lymphomas, peripheral T-cell lymphomas (PTCL) account for a disproportionate proportion of patient mortality. Conventional therapies are derived from experience treating aggressive B-cell lymphomas and center around CHOP-based chemotherapy. However, due to the unique biology and diverse subtypes of PTCL, most patients fail to durably respond to this approach and 5-year survival is only 20% to 30%. There have been multiple attempts to improve outcomes for patients with PTCL. Among the more successful strategies are the use of consolidative autologous stem cell transplant, the augmentation of CHOP with etoposide (CHOEP), and the use of brentuximab vedotin in CD30-positive PTCL. Advances in the understanding of histology-specific biology has cultivated enthusiasm to evaluate hypomethylating agents, histone deacetylate inhibitors, and phosphoinositol-3-kinase inhibitors in the frontline setting. Improvements in monitoring disease response and prognostication including the use of cell-free DNA, mutational profiling, and interim PET/CT imaging are also on the horizon. For patients with acute T-cell leukemia/lymphoma, the use of mogamulizumab-based therapy in the frontline setting may lead to advances in care. The true impact of these new-era therapies will only be elucidated as clinical practices incorporate the rapidly changing evidence.

Predictive model for treatment outcomes of peripheral T-cell lymphoma, not otherwise specified, in Taiwanese patients

PURPOSE

We aimed to explore the clinical outcomes and prognostic factors for PTCL-NOS patients in the real world.

METHODS

Clinical data were retrospectively collected from adult patients with PTCL-NOS treated at a single center in Taiwan.

RESULTS

104 PTCL-NOS patients with a median age of 53.0 years were enrolled. Patients with the International Prognostic Index (IPI) or prognostic index for peripheral T-cell lymphoma (PIT) scores of zero had a longer overall survival (OS) and progression free survival (PFS), while patients with IPI or PIT scores ≥1 did poorly. For patients who are eligible for transplantation, the use of pralatrexate as salvage chemotherapy has shown better OS (2-year OS 83.3% vs. 24.4%, P = 0.011) compared to patients who did not. By multivariate analysis, age >60 years, male, B symptoms, ECOG >1, lung involvement, and thrombocytopenia were independent adverse factors for OS. Incorporating factors in multivariate analysis, we established a novel predictive index for PTCL-NOS which efficiently stratifies patients into low (0-1 factor), intermediate-1 (2 factors), intermediate-2 (3 factors), and high risk (4-6 factors) groups with 2-year OS rates of 81.5%, 32.9%, 8.8%, and 0%, respectively (P < 0.001).

CONCLUSION

PTCL-NOS patients have a dismal prognosis in Taiwan. Novel agents may improve the outcomes of PTCL-NOS patients. The usefulness of the novel prognostic index for PTCL-NOS needs further validation.

Peripheral T-Cell Lymphoma in a Patient Previously Diagnosed With Sarcoidosis

Sarcoidosis is a multisystem disorder characterized by granulomatous inflammation on histopathological evaluation. Diagnosis of sarcoidosis requires thorough elimination of malignancy and alternative causes of noncaseating granulomatous inflammation. Sarcoidosis and several subtypes of lymphoma have similar clinical presentations and can potentially have similar histopathological findings. Patients with a histopathology-confirmed diagnosis of sarcoidosis are at higher risk of developing malignancies. In this report, we present a case of a 64-year-old male diagnosed with sarcoidosis 2 years before presenting to the emergency department with a 4-month history of generalized weakness, cough, and very high fever. After a thorough workup involving cervical lymph node biopsy and bone marrow biopsy, he was diagnosed with peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS). Due to the patient's current lymphoma diagnosis and features noted on pathology, a retrospective review of the prior biopsy specimen was performed, finding similar hematopathological features on both initial lymph node biopsy diagnosing sarcoidosis and current biopsies diagnosing lymphoma. Given these findings, our patient likely had early manifestation of PTCL misdiagnosed as sarcoidosis. In summary, lymphoma should be considered in all patients with suspected sarcoidosis, especially those who do not respond to treatment or who present with persistent hematological abnormalities.

Long-term Outcomes After Hematopoietic Cell Transplant in Peripheral T-Cell Lymphoma - The Oregon Health and Science University Experience

BACKGROUND

Peripheral T-cell lymphomas (PTCL) are a group of aggressive malignancies with inferior outcomes compared to B-cell non-Hodgkin lymphoma (NHL). Both allogeneic and autologous hematopoietic cell transplantation (HCT) are commonly employed for consolidation and salvage.

MATERIALS AND METHODS

We conducted a single-center review of all adult PTCL patients at OHSU who received HCT from 1991 to 2020 with responses assed by CIBMTR criteria.

RESULTS

88 patients (autoHCT = 52, alloHCT = 36) were identified from the internal registry of ∼3800 autoHCT & alloHCT recipients in that time period. Median OS after autoHCT and alloHCT were 7.0 and 2.6 years. Median PFS after autoHCT and alloHCT was 3.9 vs 1.1 years. Post-HCT median OS for ALCL, AITL, and PTCL NOS were 14.9, 3.9, and 3.4 years, respectively. Median PFS after autoHCT performed while in CR vs. not in CR was 3.4 vs 4.2 years (P = 0.86); for alloHCT in CR vs. not CR 2.4 vs 0.7 years (P = 0.28). 1-year non-relapse mortality (NRM) for autoHCT and alloHCT were 6.1% and 22.2% (P = 0.2). 10/88 patients developed secondary malignancies including 4 skin cancers, 3 new lymphomas, and 2 MDS.

CONCLUSION

Our experience with HCT for PTCL shows that HCT has acceptable toxicities and relatively long disease remissions. AutoHCT was most frequently utilized as planned remission consolidation while alloHCT was most often used late during salvage. Differences in response between autoHCT and alloHCT likely reflect differences in clinical setting and underlying disease natural history and biology.

Advances and challenges of immunotherapies in NK/T cell lymphomas

Natural killer (NK)/T cell lymphoma (NKTCL) is a rare subtype of Epstein-Barr virus (EBV)-associated non-Hodgkin lymphoma characterized by poor clinical outcomes. It is more common in East Asian and Latin American countries. Despite the introduction of asparaginase/pegaspargase-based chemotherapy, the prognosis of patients with advanced NKTCL needs to be improved, and few salvage treatment options are available for relapsed/refractory patients who fail chemotherapy. Although many unknowns remain, novel treatment strategies to further improve outcomes are urgently needed. Immunotherapy has emerged and shown favorable antitumor activity in NKTCL, including monoclonal antibodies targeting immune checkpoint inhibitors, other receptors on the cellular membrane, and cellular immunotherapy, which could enhance immune cells attack on tumor cells. In this review, we provide an overview of recent immunotherapy in NKTCL, focusing on programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1), cytotoxic T lymphocyte-associated protein 4 (CTLA-4), chimeric antigen receptor (CAR) T cells, EBV-specific cytotoxic T lymphocytes, immunomodulatory agents, and other targeted agents, as well as the current progress and challenges in the field.

On the Precipice of a "Rituximab-Like" Era for T-Cell Lymphomas?

To date, mAbs have had limited success in improving outcomes for patients with T-cell lymphomas. Preclinical data suggest that anti-T-cell receptor Vβ-segment mAbs are a novel therapeutic strategy for patients with T-cell lymphomas that avoid several limitations of current therapies. See related article by Lucero et al., p. 4230.

A Rare Case of CD4 Positive Cytotoxic PTCL, NOS With Leukemic Presentation

Peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) is a relatively rare mature T-cell lymphoma that cannot be categorized under any of the well-defined category. This type of aggressive lymphoma mostly involves the lymph nodes, though any other organ can be affected. Leukemic presentation is extremely rare. No case report of isolated leukemic presentation was found after detail literature search. Herein we present a case of PTCL, NOS with leukemic presentation.

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.

Retrospective Analysis With Propensity Score Matching of Peripheral T-Cell Lymphoma Treated Frontline With Brentuximab Vedotin and Chemotherapy

BACKGROUND

Since Food and Drug Administration approval of brentuximab vedotin in combination with cyclophosphamide, doxorubicin, and prednisone (A + CHP) as initial therapy for previously untreated CD30-expressing peripheral T-cell lymphoma (PTCL), there has been limited research on real-world patient characteristics, treatment patterns, and clinical outcomes.

METHODS

We retrospectively analyzed claims of patients with PTCL treated with frontline A + CHP or CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) using the Symphony Health Solutions database. Adults with International Classification of Diseases-9/10 PTCL diagnosis codes who initiated A + CHP or CHOP between November 2018 and July 2021 were included. A 1:1 propensity score matching analysis was performed that adjusted for potential confounders between groups.

RESULTS

A total of 1344 patients were included (A + CHP, n = 749; CHOP, n = 595). Before matching, 61% were men; median age at index was 62 (A + CHP) and 69 (CHOP) years. The most common A + CHP-treated PTCL subtypes were systemic anaplastic large cell lymphoma (sALCL; 51%), PTCL-not otherwise specified (NOS; 30%), and angioimmunoblastic T-cell lymphoma (AITL; 12%); the most common CHOP-treated subtypes were PTCL-NOS (51%) and AITL (19%). After matching, similar proportions of patients treated with A + CHP and CHOP received granulocyte colony-stimulating factor (89% vs. 86%, P = .3). Fewer patients treated with A + CHP received subsequent therapy than CHOP overall (20% vs. 30%, P < .001) and specifically with the sALCL subtype (15% vs. 28%, P = .025).

CONCLUSIONS

Characteristics and management of this real-world PTCL population who were older and had a higher comorbidity burden than that in the ECHELON-2 trial demonstrate the importance of retrospective studies when assessing the impact of new regimens on clinical practice.

Novel Drugs and Radiotherapy in Relapsed Lymphomas: Abscopal Response and Beyond

Combined modality has represented a mainstay of treatment across many lymphoma histologies, given their sensitivity to both multi-agent chemotherapy and intermediate-dose radiotherapy. More recently, several new agents, including immunotherapies, have reshaped the therapeutic panorama of some lymphomas. In parallel, radiotherapy techniques have witnessed substantial improvement, accompanied by a growing understanding that radiation itself comes with an immune-mediated effect. Six decades after a metastatic lesion regression outside the irradiated field was first described, there is increasing evidence that a combination of radiotherapy and immunotherapy could boost an abscopal effect. This review focuses on the mechanisms underlying this interaction in the setting of lymphomas, and on the results of pivotal prospective studies. Furthermore, the available evidence on the concomitant use of radiotherapy and small molecules (i.e., lenalidomide, venetoclax, and ibrutinib), as well as brentuximab vedotin, and chimeric antigen receptor (CAR) T-cell therapy, is summarized. Currently, combining radiotherapy with new agents in patients who are affected by lymphomas appears feasible, particularly as a bridge to anti-CD19 autologous CAR T-cell infusion. However, more studies are required to assess these combinations, and preliminary data suggest only a synergistic rather than a curative effect.

Education and Empowering Special Forces to Eradicate Secret Defectors: Immune System-Based Treatment Approaches for Mature T- and NK-Cell Malignancies

Mature T- and NK-cell leukemia/lymphoma (MTCL/L) constitute a heterogeneous group of, currently, 30 distinct neoplastic entities that are overall rare, and all present with a challenging molecular markup. Thus, so far, the use of first-line cancer treatment modalities, including chemotherapies, achieve only limited clinical responses associated with discouraging prognoses. Recently, cancer immunotherapy has evolved rapidly, allowing us to help patients with, e.g., solid tumors and also relapsed/refractory B-cell malignancies to achieve durable clinical responses. In this review, we systematically unveiled the distinct immunotherapeutic approaches available, emphasizing the special impediments faced when trying to employ immune system defense mechanisms to target 'one of their own-gone mad'. We summarized the preclinical and clinical efforts made to employ the various platforms of cancer immunotherapies including antibody-drug conjugates, monoclonal as well as bispecific antibodies, immune-checkpoint blockades, and CAR T cell therapies. We emphasized the challenges to, but also the goals of, what needs to be done to achieve similar successes as seen for B-cell entities.

Estimating long-term progression-free and overall survival in patients with peripheral T-cell lymphoma: A US population-based oncology simulation model based on 5-year results from the ECHELON-2 trial

BACKGROUND: The ECHELON-2 5-year update showed continued clinically meaningful improvements in progression-free survival (PFS) and overall survival with frontline (1L) A+CHP (brentuximab vedotin in combination with cyclophosphamide, doxorubicin, prednisone) vs CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) in CD30-expressing peripheral T-cell lymphomas (PTCLs). OBJECTIVE: To estimate PTCL annual prevalence in the United States in 2031 without and with A+CHP using data from the ECHELON-2 5-year update. METHODS: Population-level outcomes were estimated using a dynamic oncology simulation model. Utilization of 1L CHOP (65% utilization) and CHOP plus etoposide (35% utilization) were varied over time and compared with scenarios incorporating 1L A+CHP (20%-50% utilization; base case: 40% utilization) per expert clinicians' opinion. Additional inputs included PTCL incidence and PFS for consolidation and post-1L therapies from published sources. PFS (51.4% [95% CI = 42.8%-59.4%] vs 43.0% [35.8%-50.0%]) and overall survival (hazard ratio = 0.72 [0.53-0.99]) for A+CHP and CHOP came from ECHELON-2. RESULTS: In 2031, an estimated 2,082 patients will be diagnosed with PTCL. Approximately 1,412 additional patients will be alive and progression free, and 106 fewer patients will require second-line therapy with 40% A+CHP utilization vs no A+CHP utilization. Varying 1L A+CHP utilization from 20%-50% vs no 1L A+CHP utilization added 732 to 1,752 patients alive and progression free. CONCLUSIONS: In this oncology simulation model, the improvements in survival outcomes seen with A+CHP vs CHOP in the ECHELON-2 5-year results translated into more estimated patients with PTCL progression free and alive for at least 5 years following 1L A+CHP vs CHOP and a decreased need for post-1L therapy. DISCLOSURES: This study was funded by Seagen Inc. Dr Liu and Dr Yu are employees and shareholders of Seagen Inc. Mr Bloudek is and Dr Mordi was an employee of Curta Health, which received funding from Seagen Inc. for the conduct of this study. Dr Burke received consulting fees from Genentech/Roche, AbbVie, Seattle Genetics, Bayer, AstraZeneca, Adaptive Biotechnologies, Verastem, MorphoSys, Kura, Epizyme, BeiGene, Kymera, Novartis, Bristol Myers Squibb, TG Therapeutics, Lilly, and Nurix; and received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events in speakers bureaus for BeiGene and Seagen Inc. Dr Phillips received consulting fees from AstraZeneca, MorphoSys, Epizyme, Roche/Genentech, Epizyme Eli Lilly, AbbVie, BeiGene, Pharmacyclics, Bristol Myers Squibb, Xencor, Seagen Inc., TG Therapeutics, Bayer, Incyte, and Gilead; and received payment for honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Epizyme and Seagen Inc.

Aberrant JAK-STAT signaling-mediated chromatin remodeling impairs the sensitivity of NK/T-cell lymphoma to chidamide

BACKGROUND

Natural killer/T-cell lymphoma (NKTL) is a rare type of aggressive and heterogeneous non-Hodgkin's lymphoma (NHL) with a poor prognosis and limited therapeutic options. Therefore, there is an urgent need to exploit potential novel therapeutic targets for the treatment of NKTL. Histone deacetylase (HDAC) inhibitor chidamide was recently approved for treating relapsed/refractory peripheral T-cell lymphoma (PTCL) patients. However, its therapeutic efficacy in NKTL remains unclear.

METHODS

We performed a phase II clinical trial to evaluate the efficacy of chidamide in 28 relapsed/refractory NKTL patients. Integrative transcriptomic, chromatin profiling analysis and functional studies were performed to identify potential predictive biomarkers and unravel the mechanisms of resistance to chidamide. Immunohistochemistry (IHC) was used to validate the predictive biomarkers in tumors from the clinical trial.

RESULTS

We demonstrated that chidamide is effective in treating relapsed/refractory NKTL patients, achieving an overall response and complete response rate of 39 and 18%, respectively. In vitro studies showed that hyperactivity of JAK-STAT signaling in NKTL cell lines was associated with the resistance to chidamide. Mechanistically, our results revealed that aberrant JAK-STAT signaling remodels the chromatin and confers resistance to chidamide. Subsequently, inhibition of JAK-STAT activity could overcome resistance to chidamide by reprogramming the chromatin from a resistant to sensitive state, leading to synergistic anti-tumor effect in vitro and in vivo. More importantly, our clinical data demonstrated that combinatorial therapy with chidamide and JAK inhibitor ruxolitinib is effective against chidamide-resistant NKTL. In addition, we identified TNFRSF8 (CD30), a downstream target of the JAK-STAT pathway, as a potential biomarker that could predict NKTL sensitivity to chidamide.

CONCLUSIONS

Our study suggests that chidamide, in combination with JAK-STAT inhibitors, can be a novel targeted therapy in the standard of care for NKTL.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02878278. Registered 25 August 2016, https://clinicaltrials.gov/ct2/show/NCT02878278.

Emerging predictive biomarkers for novel therapeutics in peripheral T-cell and natural killer/T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) and natural killer/T-cell lymphoma (NKTCL) are rare subtypes of non-Hodgkin's lymphoma that are typically associated with poor treatment outcomes. Contemporary first-line treatment strategies generally involve the use of combination chemoimmunotherapy, radiation and/or stem cell transplant. Salvage options incorporate a number of novel agents including epigenetic therapies (e.g. HDAC inhibitors, DNMT inhibitors) as well as immune checkpoint inhibitors. However, validated biomarkers to select patients for individualized precision therapy are presently lacking, resulting in high treatment failure rates, unnecessary exposure to drug toxicities, and missed treatment opportunities. Recent advances in research on the tumor and microenvironmental factors of PTCL and NKTCL, including alterations in specific molecular features and immune signatures, have improved our understanding of these diseases, though several issues continue to impede progress in clinical translation. In this Review, we summarize the progress and development of the current predictive biomarker landscape, highlight potential knowledge gaps, and discuss the implications on novel therapeutics development in PTCL and NKTCL.

Anti-CD30 antibody-drug conjugate therapy in lymphoma: current knowledge, remaining controversies, and future perspectives

CD30 is overexpressed in several lymphoma types, including classic Hodgkin lymphoma (cHL), some peripheral T-cell lymphomas (PTCL), and some cutaneous T-cell lymphomas. The antibody-drug conjugate brentuximab vedotin targets CD30-positive cells and has been evaluated for the treatment of various lymphoma entities. This narrative review summarizes 10 years of experience with brentuximab vedotin for the treatment of CD30-positive lymphomas, discusses novel therapies targeting CD30 in development, and highlights remaining controversies relating to CD30-targeted therapy across lymphoma types. The collective body of evidence for brentuximab vedotin demonstrates that exploitation of CD30 can provide sustained benefits across a range of different CD30-positive lymphomas, in both clinical trials and real-world settings. Preliminary experience with brentuximab vedotin in combination with immune checkpoint inhibitors for relapsed/refractory cHL is encouraging, but further exploration is required. The optimal use of brentuximab vedotin for first-line therapy of PTCL remains to be determined. Further research is required on brentuximab vedotin treatment in high-risk patient populations, and in rare lymphoma subtypes, for which no standard of care exists. Novel therapies targeting CD30 include chimeric antigen receptor therapies and bispecific antibody T-cell engagers, which may be expected to further improve outcomes for patients with CD30-positive lymphomas in the coming years.

Extranodal T- and NK-cell lymphomas

Non-cutaneous extranodal NK/T cell lymphoproliferations constitute a heterogenous group of rare neoplasms, occurring primarily in the gastro-intestinal tract, nasal area, spleen, and liver. Their nomenclature refers to their usual clinical presentation and predilection for specific anatomic sites-i.e. extranodal NK/T-cell lymphoma, nasal-type, hepatosplenic T-cell lymphoma, primary intestinal T-cell lymphomas, indolent lymphoproliferative disorders of the gastrointestinal tract, and breast implant-associated anaplastic large cell lymphoma. Extranodal tissues may also be involved by T-cell leukemias, or other entities usually presenting as nodal diseases. Primary extranodal entities range from indolent to highly aggressive diseases. Here, we will review the clinicopathologic features of the pertinent entities including the recent advances in their molecular and genetic characterization, with an emphasis on the changes introduced in the 2022 International Consensus Classification of lymphoid neoplasms, and highlight the diagnostic criteria helpful to sort out the distinction with potential mimickers.

Current state of CAR-T therapy for T-cell malignancies

Chimeric antigen receptor T-cell (CAR-T) therapy has been approved for relapsed/refractory B-cell lymphomas and greatly improves disease outcomes. The impressive success has inspired the application of this approach to other types of tumors. The relapsed/refractory T-cell malignancies are characteristic of high heterogeneity and poor prognoses. The efficacy of current treatments for this group of diseases is limited. CAR-T therapy is a promising solution to ameliorate the current therapeutic situation. One of the major challenges is that normal T-cells typically share mutual antigens with malignant cells, which causes fratricide and serious T-cell aplasia. Moreover, T-cells collected for CAR transduction could be contaminated by malignant T-cells. The selection of suitable target antigens is of vital importance to mitigate fratricide and T-cell aplasia. Using nanobody-derived or naturally selected CAR-T is the latest method to overcome fratricide. Allogeneic CAR-T products and CAR-NK-cells are expected to avoid tumor contamination. Herein, we review the advances in promising target antigens, the current results of CAR-T therapy clinical trials in T-cell malignancies, the obstacles of CAR-T therapy in T-cell malignancies, and the solutions to these issues.

Harnessing the Potential of Chimeric Antigen Receptor T-Cell Therapy for the Treatment of T-Cell Malignancies: A Dare or Double Dare?

Historical standard of care treatments of T-cell malignancies generally entailed the use of cytotoxic and depleting approaches. These strategies are, however, poorly validated and record dismal long-term outcomes. More recently, the introduction and approval of chimeric antigen receptor (CAR)-T cell therapy has revolutionized the therapy of B-cell malignancies. Translating this success to the T-cell compartment has so far proven hazardous, entangled by risks of fratricide, T-cell aplasia, and product contamination by malignant cells. Several strategies have been utilized to overcome these challenges. These include the targeting of a selective cognate antigen exclusive to T-cells or a subset of T-cells, disruption of target antigen expression on CAR-T constructs, use of safety switches, non-viral transduction, and the introduction of allogeneic compounds and gene editing technologies. We herein overview these historical challenges and revisit the opportunities provided as potential solutions. An in-depth understanding of the tumor microenvironment is required to optimally harness the potential of the immune system to treat T-cell malignancies.

In silico analysis of a novel protein in CAR T- cell therapy for the treatment of hematologic cancer through molecular modelling, docking, and dynamics approach

Cellular therapy has emerged as a key tool in the treatment of hematological malignancies. An advanced cell therapy known as chimeric antigen receptor T cell therapy (CAR T-cell therapy) has been approved by the United States Food and Drug Administration (FDA) as KYMRIAH by Novartis and YESCARTA by Gilead/Kite pharma in the year 2017. A chimeric receptor is composed of an extracellular antigen recognition site along with some co-stimulating and signalling domains. On the whole, it turns out to be one of the most potent receptors on T cells targeting a specific type of cancer cell based on its antigenic marker. CD19 CAR T-cell therapy is the first clinically approved therapy for lymphoma with remarkable results in complete remission of B cell lymphoblastic leukemia up to 90%. The high rate of effectiveness of the CAR T-cell therapy against B-ALL justifies the investigation and application of this therapy for fatal diseases like all types of hematological malignancies. The most critical aspect of chimeric receptor therapy is designing and building an artificial receptor that is specific to a given type of cancer. For this reason, the in silico technique is an appropriate model to investigate the integrity and effectiveness of the engineered chimeric receptor prior to commencing in vitro experiments followed by clinical trials. This computerized experimental study aids in predicting the molecular mechanism of chimeric protein and how it interacts with both ligands. We have anticipated various features of the chimeric protein in terms of qualitative analysis (structure, protein modelling, physiological properties) and functional analysis (antigenicity, allergenicity, its receptor-ligand binding ability, involving signalling pathways). Furthermore, the reliability and validation of the binding mode of the chimeric protein against receptors were performed through a complex molecular dynamics simulation for a 100 ns timeframe in an aqueous environment. The obtained simulation study showed that CD30 was a better approachable marker as compared to CD20 due to its better binding energy score and also binding conformations stability.

Response to Brentuximab Vedotin by CD30 Expression in Non-Hodgkin Lymphoma

Background

The safety and efficacy of brentuximab vedotin (BV), an antibody-drug conjugate directed to the CD30 antigen, has been assessed in several trials in patients with peripheral T-cell lymphoma (PTCL), cutaneous T-cell lymphoma (CTCL), or B-cell non-Hodgkin lymphoma (NHL). The objective of this research was to examine the relationship between CD30 expression level and clinical response to BV.

Patients and Methods

We analyzed response in patients treated with BV monotherapy in 5 prospective clinical studies in relapsed or refractory PTCL, CTCL, or B-cell NHL. CD30 expression was assessed by immunohistochemistry (IHC) using the Ber H2 antibody for 275 patients.

Results

Across all 5 studies, 140 (50.9%) patients had tumors with CD30 expression <10%, including 60 (21.8%) with undetectable CD30 by IHC. No significant differences were observed for any study in overall response rates between patients with CD30 expression ≥10% or <10%. Median duration of response was also similar in the CD30 ≥10% and <10% groups for all studies.

Conclusions

In this analysis of studies across a range of CD30-expressing lymphomas, CD30 expression alone, as measured by standard IHC, does not predict clinical benefit from BV, making the determination of a threshold level of expression uncertain.

Recent Advances in the Management of Relapsed and Refractory Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a group of heterogeneous lymphomas with poor overall prognosis, particularly in the setting of relapsed/refractory PTCL. Given the limited efficacy of current therapies, several different novel therapies encompassing multiple different mechanisms of action have been evaluated for relapsed and refractory PTCLs. In this review, we explore the current standard of care for relapsed/refractory PTCL, and evaluate in depth novel and emerging therapies, their scientific basis, and current trials for relapsed/refractory PTCL.

Novel T Follicular Helper-like T-Cell Lymphoma Therapies: From Preclinical Evaluation to Clinical Reality

Simple Summary

This work reviews the multiple efforts that have been and are being invested by researchers as well as clinicians to improve the treatment of a specific T-cell lymphoma called follicular helper peripheral T-cell lymphoma. Still, though treatments for B-cell lymphomas have improved, this particular T-cell lymphoma has little to no new therapeutic options that show marked improvements in the survival of the patients compared to treatment with chemotherapy. We report here the evaluation of targeted new therapies for this T-cell lymphoma in new preclinical models for this cancer or in clinical trials with the objective to offer better (combination) treatment options.

Abstract

The classification of peripheral T-cell lymphomas (PTCL) is constantly changing and contains multiple subtypes. Here, we focus on Tfh-like PTCL, to which angioimmunoblastic T-cell lymphoma (AITL) belongs, according to the last WHO classification. The first-line treatment of these malignancies still relies on chemotherapy but gives very unsatisfying results for these patients. Enormous progress in the last decade in terms of understanding the implicated genetic mutations leading to signaling and epigenetic pathway deregulation in Tfh PTCL allowed the research community to propose new therapeutic approaches. These findings point towards new biomarkers and new therapies, including hypomethylating agents, such as azacytidine, and inhibitors of the TCR-hyperactivating molecules in Tfh PTCL. Additionally, metabolic interference, inhibitors of the NF-κB and PI3K-mTOR pathways and possibly novel immunotherapies, such as antibodies and chimeric antigen receptors (CAR) directed against Tfh malignant T-cell surface markers, are discussed in this review among other new treatment options.

Chimeric Antigen Receptor Based Cellular Therapy for Treatment Of T-Cell Malignancies

T-cell malignancies can be divided into precursor (T-acute lymphoblastic leukemia/lymphoblastic lymphoma, T-ALL/LBL) and mature T-cell neoplasms, which are comprised of 28 different entities. Most of these malignancies are aggressive with rather poor prognosis. Prognosis of relapsed/refractory (R/R) disease is especially dismal, with an expected survival only several months after progression. Targeted therapies, such as antiCD30 immunotoxin brentuximab vedotin, antiCD38 antibody daratumumab, and anti-CCR4 antibody mogamulizumab are effective only in subsets of patients with T-cell neoplasms. T-cells equipped with chimeric antigen receptor (CAR-Ts) are routinely used for treatment of R/R B-cell malignancies, however, there are specific obstacles for their use in T-cell leukemias and lymphomas which are fratricide killing, risk of transfection of malignant cells, and T-cell aplasia. The solution for these problems relies on target antigen selection, CRISPR/Cas9 or TALEN gene editing, posttranslational regulation of CAR-T surface antigen expression, and safety switches. Structural chromosomal changes and global changes in gene expression were observed with gene-edited products. We identified 49 studies of CAR-based therapies registered on www.clinicaltrials.gov. Most of them target CD30 or CD7 antigen. Results are available only for a minority of these studies. In general, clinical responses are above 50% but reported follow-up is very short. Specific toxicities of CAR-based therapies, namely cytokine release syndrome (CRS), seem to be connected with the antigen of interest and source of cells for manufacturing. CRS is more frequent in antiCD7 CAR-T cells than in antiCD30 cells, but it is mild in most patients. More severe CRS was observed after gene-edited allogeneic CAR-T cells. Immune effector cell associated neurotoxicity (ICANS) was mild and infrequent. Graft-versus-host disease (GvHD) after allogeneic CAR-T cells from previous hematopoietic stem cell donor was also observed. Most frequent toxicities, similarly to antiCD19 CAR-T cells, are cytopenias. CAR-based cellular therapy seems feasible and effective for T-cell malignancies, however, the optimal design of CAR-based products is still unknown and long-term follow-up is needed for evaluation of their true potential.

Basic immunohistochemistry for lymphoma diagnosis

Immunohistochemistry is a technique that uses antigen-antibody interactions to detect specific proteins in cells. This technique has several essential applications in lymphoma diagnosis, including identifying the cell lineage and phase of maturation, detecting specific genetic alterations, visualizing the degree of cell proliferation, and identifying therapeutic targets. CD3 is a pan T-cell marker expressed on most of the mature T/NK-cell lymphomas, except for anaplastic large cell lymphoma, whereas CD20 is a pan B-cell marker that is expressed on most of the mature B-cell lymphomas. CD79a may be a good alternative to CD20, compensating for its loss owing to the plasmocytic differentiation of tumor cells or history of rituximab administration. CD56, a neuroendocrine marker, is used as an NK cell marker in lymphoma diagnosis. Characteristic translocations occurring in follicular lymphoma (BCL2) and mantle cell lymphoma (CCND1) can be detected by the overexpression of Bcl-2 and cyclin D-1 in immunohistochemistry, respectively. Ki-67 reflects the degree of tumor cell proliferation by indicating cells in cell cycle phases other than G0. With the development of immunotherapy, several antibodies against markers such as programmed death-ligand 1 (PD-L1), CD19, and CD30 have been used as biomarkers to identify therapeutic targets. It is critical to properly fix the specimens to obtain accurate immunohistochemical results. Therefore, all processes, from tissue collection to the final pathological diagnosis, must be performed appropriately for accurate lymphoma diagnosis.

T-Cell Lymphomas, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of lymphoproliferative disorders arising from mature T cells, accounting for about 10% of non-Hodgkin lymphomas. PTCL-not otherwise specified is the most common subtype, followed by angioimmunoblastic T-cell lymphoma, anaplastic large cell lymphoma, anaplastic lymphoma kinase-positive, anaplastic large cell lymphoma, anaplastic lymphoma kinase-negative, and enteropathy-associated T-cell lymphoma. This discussion section focuses on the diagnosis and treatment of PTCLs as outlined in the NCCN Guidelines for T-Cell Lymphomas.

The ECHELON-2 Trial: 5-year results of a randomized, phase III study of brentuximab vedotin with chemotherapy for CD30-positive peripheral T-cell lymphoma

BACKGROUND

For patients with peripheral T-cell lymphoma (PTCL), outcomes using frontline treatment with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP-like therapy are typically poor. The ECHELON-2 study demonstrated that brentuximab vedotin plus cyclophosphamide, doxorubicin, and prednisone (A+CHP) exhibited statistically superior progression-free survival (PFS) per independent central review and improvements in overall survival versus CHOP for the frontline treatment of patients with systemic anaplastic large cell lymphoma or other CD30-positive PTCL.

PATIENTS AND METHODS

ECHELON-2 is a double-blind, double-dummy, randomized, placebo-controlled, active-comparator phase III study. We present an exploratory update of the ECHELON-2 study, including an analysis of 5-year PFS per investigator in the intent-to-treat analysis group.

RESULTS

A total of 452 patients were randomized (1 : 1) to six or eight cycles of A+CHP (N = 226) or CHOP (N = 226). At median follow-up of 47.6 months, 5-year PFS rates were 51.4% [95% confidence interval (CI): 42.8% to 59.4%] with A+CHP versus 43.0% (95% CI: 35.8% to 50.0%) with CHOP (hazard ratio = 0.70; 95% CI: 0.53-0.91), and 5-year overall survival (OS) rates were 70.1% (95% CI: 63.3% to 75.9%) with A+CHP versus 61.0% (95% CI: 54.0% to 67.3%) with CHOP (hazard ratio = 0.72; 95% CI: 0.53-0.99). Both PFS and OS were generally consistent across key subgroups. Peripheral neuropathy was resolved or improved in 72% (84/117) of patients in the A+CHP arm and 78% (97/124) in the CHOP arm. Among patients who relapsed and subsequently received brentuximab vedotin, the objective response rate was 59% with brentuximab vedotin retreatment after A+CHP and 50% with subsequent brentuximab vedotin after CHOP.

CONCLUSIONS

In this 5-year update of ECHELON-2, frontline treatment of patients with PTCL with A+CHP continues to provide clinically meaningful improvement in PFS and OS versus CHOP, with a manageable safety profile, including continued resolution or improvement of peripheral neuropathy.

Advances and Personalized Approaches in the Frontline Treatment of T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a rare and heterogenous subset of non-Hodgkin lymphoma characterized by an aggressive clinical course. Historically, the treatment of PTCLs have been analogous to that of aggressive B-cell lymphomas; however, it has been well-established that overall responses and complete remission rates are far inferior using near-identical chemotherapy strategies. Recently, there has been a plethora of newer agents designed to target distinguishing cellular and molecular features of specific PTCL subtypes. These agents have been proven to yield superior anti-lymphoma responses and, in some cases, overall survival in the relapsed, refractory, and frontline treatment setting. In this review, we will summarize and highlight the most influential clinical trials leading to the Food and Drug Administration (FDA) approval of several novel therapeutic agents against PTCL, with an emphasis on emerging studies and strategies to expand their potential use in the frontline treatment setting.