PTCL, NOS: An update on classification, risk-stratification, and treatment

The efficacy and safety of brentuximab vedotin for peripheral T-cell lymphoma: A systemic review and meta-analysis

Peripheral T-cell lymphoma (PTCL) is an extensive class of heterogeneous diseases with dismal outcomes. Brentuximab vedotin (BV) is an antibody-drug conjugate (ADC) comprising a CD30-directed antibody. This review aimed to evaluate the efficacy and safety of BV for treating PTCL. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for studies evaluating the efficacy of BV alone or in combination with other drugs for treating PTCL. The primary outcome measures included objective response rate (ORR), complete remission (CR), progression-free survival (PFS), and overall survival (OS). The secondary outcomes included 5-year OS, 5-year PFS, and adverse events. 22 studies involving 1137 patients were included. These studies reported the use patterns of BV, ORR, CR, PFS, OS, and adverse events. The pooled ORR and CR rates were 68% (95% CI: 59%-75%) and 43% (95% CI: 34%-53%). For survival outcomes, the longest median PFS was 8.3 months, and the longest median OS was 26.3 months. The most common adverse event was peripheral neuropathy and neutropenia. The analysis suggested that BV alone or in combination with other drugs improved the response and survival rates in PTCL patients and was associated with tolerable adverse effects.

Implementation of the recommended immunohistochemistry algorithm for classification of peripheral T-cell lymphoma, not otherwise specified into the prognostically significant GATA3 and TBX21 subtypes

INTRODUCTION

Current molecular research has shown the several oncogenic pathways that give rise to the peripheral T-cell lymphoma, not otherwise defined (PTCL, NOS) subtypes, which alter prognosis and might have predictive value. This study was conducted to assess the immunohistochemistry (IHC) algorithm by Amador et al for the subtyping of PTCL, NOS and determine its applicability in relation to the clinicopathological profile.

METHODS

This study included 43 patients with PTCL, NOS diagnosis. Following the use of IHC for the transcription factors GATA3, TBX21, CCR4, and CXCR3, two pathologists subtyped the samples. Comprehensive clinicopathological correlation was carried out.

RESULTS

Applying the algorithm of Amador et al., cases were classified into GATA3 (20), TBX21 (15), and unclassified (8) subtypes. No significant association with clinical parameters of subtypes or CD4/ CD8 positivity was observed. Although a higher proportion of cases in the TBX21 subgroup showed a polymorphic population compared with the GATA3 subgroup, which had a monomorphic population, no significant p-value (0.111) was observed. Two Lennert lymphomas were classified into the GATA3 subgroup. Multivariate analysis showed no significant difference in overall survival (p-value = 0.105) and progression-free survival (p-value = 0.0509) between IHC-defined subtypes; trends indicate that overall survival and progression-free survival are worse in the GATA3 subgroup.

CONCLUSION

Although the algorithm is reproducible, a proportion of cases remains unclassifiable and may require additional investigation and gene expression profiling. The GATA3 subgroup was found to have a monomorphic population with a poor overall prognosis and thus requires a larger sample size for validation.

Possible role of a malfunctioning immune system in discordant lymphoma with peripheral T‑cell lymphoma secondary to classical Hodgkin lymphoma: A case report

The present case report investigated the clinicopathological features and potential mechanisms underlying the transformation to peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), following treatment for classical Hodgkin lymphoma (CHL) in a 73-year-old man. The patient was admitted to hospital in 2012 and underwent a left cervical lymph node biopsy, which confirmed CHL of the nodular sclerosing type, with evident bone marrow involvement. The patient received four cycles of doxorubicin, bleomycin, vinblastine and dacarbazine chemotherapy, after which they achieved complete remission. However, after 3 years, the patient presented with enlarged left inguinal lymph nodes and a biopsy revealed PTCL-NOS. Molecular studies indicated a T-cell receptor-γ gene rearrangement. A literature review, together with the current case, identified 11 patients with CHL that transformed into PTCL-NOS. Among these, nine patients (81.82%) were middle-aged or elderly (>45 years old), and eight (72.73%) experienced transformation within 3 years post-treatment of CHL. Among these eight patients, seven (87.50%) predominantly exhibited the nodular sclerosis subtype, with a median recurrence time of 26 months. Five (45.45%) patients died of the disease. The rare transformation of CHL to PTCL-NOS, primarily among men, underscores its clinical significance. Notably, nodular sclerosing-type CHL appears to be particularly prone to transformation into PTCL-NOS. The poor prognosis in such cases may be attributed to the complex tumor microenvironment of CHL.

Possible Association of CD3+CD4-CD8- Phenotype of T-Cell Lymphoma with Peripheral Blood Eosinophilia

INTRODUCTION

Because the prognosis of patients with peripheral T-cell lymphoma is poor compared to that of patients with B-cell lymphoma, we want to avoid further organ damage by eosinophilia. Moreover, in patients with some types of lymphoma, blood eosinophilia is implicated in a worse prognosis. To study the risk factors of eosinophilia, the association between lymphoma type, immunophenotypic features, and peripheral blood eosinophil counts were examined in the patients with mature T-cell lymphoma.

METHODS

We retrospectively examined 28 patients with mature T-cell lymphoma who were admitted to our hospital and whose immunophenotypic features were confirmed using flow cytometric, immunohistochemical analysis, or both between December 2012 and November 2023.

RESULTS

We report a possible association between peripheral eosinophilia and peripheral T-cell lymphoma - not otherwise specified and CD3+CD4-D8- (double-negative) phenotypes. Mild eosinophilia was observed in various types, but moderate and severe eosinophilia were observed in patients with peripheral T-cell lymphoma - not otherwise specified. Double-negative phenotype was rarely observed; however, all patients with double-negative phenotype exhibited peripheral blood eosinophilia. In addition, four of the five cases of the double-negative type were peripheral T-cell lymphoma - not otherwise specified.

CONCLUSION

Here, we retrospectively examined patients with peripheral T-cell lymphoma whose immunophenotypic features were confirmed and report a possible association between peripheral eosinophilia and peripheral T-cell lymphoma - not otherwise specified and CD3+CD4-CD8- (double-negative) phenotypes. In addition, clinicians should be aware of the possible risk that patients with lymphocytic hypereosinophilic syndrome of the double-negative phenotype may develop peripheral T-cell lymphoma.

Oral manifestations of peripheral T cell lymphoma, not otherwise specified: case series and review of the current literature

OBJECTIVE

The objective of this study was to describe a series of peripheral T-cell lymphoma, not otherwise specified (PTCL NOS) affecting the oral cavity and to review the available literature.

STUDY DESIGN

Cases diagnosed as PTCL-NOS affecting the oral cavity were retrospectively retrieved from pathology files. Original hematoxylin and eosin-stained slides and immunohistochemical reactions were reviewed for microscopic confirmation. The presence of Epstein-Barr virus (EBV) was investigated by in situ hybridization. Clinical and follow-up data were retrieved from patients' pathology and medical files.

RESULTS

A total of 5 cases were obtained with a mean age of 51.8 years old, 3 male patients and 2 female patients. Three cases affected the palate and 2 cases affected the gingiva, whereas 1 case affected the maxillary bone. Tumors presented as destructive, infiltrative, and painful lesions causing swelling, ulceration, and tissue necrosis. All cases exhibited CD3 expression. GATA3 was expressed in 3 cases. Four patients were deceased of the disease during follow-up.

CONCLUSIONS

PTCL NOS affecting the oral cavity is rare and usually present as a very aggressive disease, associated with a poor prognosis and dismal outcome. (Oral Surg Oral Med Oral Pathol Oral Radiol YEAR;VOL:page range).

Response to Azacytidine in a Patient With Refractory Peripheral T-cell Lymphoma With TET2 Mutation

Peripheral T-cell lymphomas (PTCLs) are an aggressive form of non-Hodgkin lymphomas. PTCLs have multiple subtypes, with PTCL not otherwise specified (PTCL-NOS) being the most common. This subtype usually has a high rate of relapse. Making an accurate diagnosis requires molecular genetic analyses, histopathological examination, and immunophenotyping. Treatment for PTCL traditionally starts with the CHOP regimen (cyclophosphamide, doxorubicin, vincristine, and prednisone). We present a case of a patient with PTCL-NOS who progressed despite multiple treatment regimens, including both traditional and novel therapeutic agents, and finally achieved good results with azacytidine, selected based on a TET2 mutation. This case proposes future research into Azacytidine's efficacy in this patient population and further exploration of the broader utility of epigenetic therapies in PTCL.

Immunogenetic Background of Chronic Lymphoproliferative Disorders in Romanian Patients-Case Control Study

BACKGROUND AND OBJECTIVES

The implications of the genetic component in the initiation and development of chronic lymphoproliferative disorders have been the subject of intense research efforts. Some of the most important genes involved in the occurrence and evolution of these pathologies are the HLA genes. The aim of this study is to analyze, for the first time, possible associations between chronic lymphoproliferative diseases and certain HLA alleles in the Romanian population.

MATERIALS AND METHODS

This study included 38 patients with chronic lymphoproliferative disorders, diagnosed between 2021 and 2022 at Fundeni Clinical Institute, Bucharest, Romania, and 50 healthy controls. HLA class I and class II genes (HLA-A/B/C, HLA-DQB1/DPB1/DRB1) were investigated by doing high resolution genotyping using sequence specific primers (SSP).

RESULTS

Several HLA alleles were strongly associated with chronic lymphoproliferative disorders. The most important finding was that the HLA-C*02:02 (p = 0.002, OR = 1.101), and HLA-C*12:02 (p = 0.002, OR = 1.101) have a predisposing role in the development of chronic lymphoproliferative disorders. Moreover, we identified that HLA-A*11:01 (p = 0.01, OR = 0.16), HLA-B*35:02 (p = 0.037, OR = 0.94), HLA-B*81:01 (p = 0.037, OR = 0.94), HLA-C*07:02 (p = 0.036, OR = 0.34), HLA-DRB1*11:01 (p = 0.021, OR = 0.19), and HLA-DRB1*13:02 (p = 0.037, OR = 0.94), alleles have protective roles.

CONCLUSIONS

Our study indicates that HLA-C*02:02 and HLA-C*12:02 are positively associated with chronic lymphoproliferative disorders for our Romanian patients while HLA-DRB1*11:01, HLA-DRB1*13:02, and HLA-B*35:02 alleles have a protective role against these diseases.

Therapeutic challenges in peripheral T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) is a rare and heterogeneous group of hematological malignancies. Compared to our knowledge of B-cell tumors, our understanding of T-cell leukemia and lymphoma remains less advanced, and a significant number of patients are diagnosed with advanced stages of the disease. Unfortunately, the development of drug resistance in tumors leads to relapsed or refractory peripheral T-Cell Lymphomas (r/r PTCL), resulting in highly unsatisfactory treatment outcomes for these patients. This review provides an overview of potential mechanisms contributing to PTCL treatment resistance, encompassing aspects such as tumor heterogeneity, tumor microenvironment, and abnormal signaling pathways in PTCL development. The existing drugs aimed at overcoming PTCL resistance and their potential resistance mechanisms are also discussed. Furthermore, a summary of ongoing clinical trials related to PTCL is presented, with the aim of aiding clinicians in making informed treatment decisions.

The Role of Epigenetic Modifier Mutations in Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a group of diseases with a low incidence, high degree of heterogeneity, and a dismal prognosis in most cases. Because of the low incidence of these diseases, there have been few therapeutic novelties developed over time. Nevertheless, this fact is changing presently as epigenetic modifiers have been shown to be recurrently mutated in some types of PTCLs, especially in the cases of PTCLs not otherwise specified (PTCL-NOS), T follicular helper (TFH), and angioimmunoblastic T-cell lymphoma (AITL). These have brought about more insight into PTCL biology, especially in the case of PTCLs arising from TFH lymphocytes. From a biological perspective, it has been observed that ten-eleven translocators (TET2) mutated T lymphocytes tend to polarize to TFH, while Tregs lose their inhibitory properties. IDH2 R172 was shown to have inhibitory effects on TET2, mimicking the effects of TET2 mutations, as well as having effects on histone methylation. DNA methyltransferase 3A (DNMT3A) loss-of-function, although it was shown to have opposite effects to TET2 from an inflammatory perspective, was also shown to increase the number of T lymphocyte progenitors. Aside from bringing about more knowledge of PTCL biology, these mutations were shown to increase the sensitivity of PTCLs to certain epigenetic therapies, like hypomethylating agents (HMAs) and histone deacetylase inhibitors (HDACis). Thus, to answer the question from the title of this review: We found the Achilles heel, but only for one of the Achilles.

Cytogenetics in the management of mature T-cell and NK-cell neoplasms: Guidelines from the Groupe Francophone de Cytogénétique Hématologique (GFCH)

Mature T-cell and natural killer (NK)-cell neoplasms (MTNKNs) are a highly heterogeneous group of lymphomas that represent 10-15 % of lymphoid neoplasms and have usually an aggressive behavior. Diagnosis can be challenging due to their overlapping clinical, histological and immunophenotypic features. Genetic data are not a routine component of the diagnostic algorithm for most MTNKNs. Indeed, unlike B-cell lymphomas, the genomic landscape of MTNKNs is not fully understood. Only few characteristic rearrangements can be easily identified with conventional cytogenetic methods and are an integral part of the diagnostic criteria, for instance the t(14;14)/inv(14) or t(X;14) abnormality harbored by 95 % of patients with T-cell prolymphocytic leukemia, or the ALK gene translocation observed in some forms of anaplastic large cell lymphoma. However, advances in molecular and cytogenetic techniques have brought new insights into MTNKN pathogenesis. Several recurrent genetic alterations have been identified, such as chromosomal losses involving tumor suppressor genes (SETD2, CDKN2A, TP53) and gains involving oncogenes (MYC), activating mutations in signaling pathways (JAK-STAT, RAS), and epigenetic dysregulation, that have improved our understanding of these pathologies. This work provides an overview of the cytogenetics knowledge in MTNKNs in the context of the new World Health Organization classification and the International Consensus Classification of hematolymphoid tumors. It describes key genetic alterations and their clinical implications. It also proposes recommendations on cytogenetic methods for MTNKN diagnosis.

Role of cytokine in malignant T-cell metabolism and subsequent alternation in T-cell tumor microenvironment

T cells are an important component of adaptive immunity and T-cell-derived lymphomas are very complex due to many functional sub-types and functional elasticity of T-cells. As with other tumors, tissues specific factors are crucial in the development of T-cell lymphomas. In addition to neoplastic cells, T- cell lymphomas consist of a tumor micro-environment composed of normal cells and stroma. Numerous studies established the qualitative and quantitative differences between the tumor microenvironment and normal cell surroundings. Interaction between the various component of the tumor microenvironment is crucial since tumor cells can change the microenvironment and vice versa. In normal T-cell development, T-cells must respond to various stimulants deferentially and during these courses of adaptation. T-cells undergo various metabolic alterations. From the stage of quiescence to attention of fully active form T-cells undergoes various stage in terms of metabolic activity. Predominantly quiescent T-cells have ATP-generating metabolism while during the proliferative stage, their metabolism tilted towards the growth-promoting pathways. In addition to this, a functionally different subset of T-cells requires to activate the different metabolic pathways, and consequently, this regulation of the metabolic pathway control activation and function of T-cells. So, it is obvious that dynamic, and well-regulated metabolic pathways are important for the normal functioning of T-cells and their interaction with the microenvironment. There are various cell signaling mechanisms of metabolism are involved in this regulation and more and more studies have suggested the involvement of additional signaling in the development of the overall metabolic phenotype of T cells. These important signaling mediators include cytokines and hormones. The impact and role of these mediators especially the cytokines on the interplay between T-cell metabolism and the interaction of T-cells with their micro-environments in the context of T-cells lymphomas are discussed in this review article.