The rapidly changing landscape in mature T-cell lymphoma (MTCL) biology and management.

Historical advances in the care of patients with non-Hodgkin lymphoma (NHL) have been restricted largely to patients with B-cell lymphoma. The peripheral T-cell lymphomas (PTCLs), which are rare and heterogeneous in nature, have yet to experience the same degree of improvement in outcome over the past 20 to 30 years. It is estimated that there are approximately 80,000 and 14,000 cases, respectively, of NHL and Hodgkin lymphoma per year in the United States. As a subgroup of NHL, the PTCLs account for 6% to 10% of all cases of NHL, making them exceedingly rare. In addition, the World Health Organization 2017 classification describes 29 distinct subtypes of PTCL. This intrinsic diversity, coupled with its rarity, has stymied progress in the disease. In addition, most subtypes carry an inferior prognosis compared with their B-cell counterparts, an outcome largely attributed to the fact that most treatment paradigms for patients with PTCL have been derived from B-cell neoplasms, a radically different disease. In fact, the first drug ever approved for patients with PTCL was approved only a decade ago. The plethora of recent drug approvals in PTCL, coupled with a deeper understanding of the molecular pathogenesis of the disease, has stimulated the field to pursue new avenues of research that are now largely predicated on the development of novel, targeted small molecules, which include a host of epigenetic modifiers and biologics. There is an expectation these advances may begin to favorably challenge the chemotherapy paradigms that have been used in the T-cell malignancies.

Unraveling clonal CD8 T cell expansion and identification of essential factors in γ-herpesvirus-induced lymphomagenesis.

Alcelaphine gammaherpesvirus 1 (AlHV-1) asymptomatically persists in its natural host, the wildebeest. However, cross-species transmission to cattle results in the induction of an acute and lethal peripheral T cell lymphoma-like disease (PTCL), named malignant catarrhal fever (MCF). Our previous findings demonstrated an essential role for viral genome maintenance in infected CD8+ T lymphocytes but the exact mechanism(s) leading to lymphoproliferation and MCF remained unknown. To decipher how AlHV-1 dysregulates T lymphocytes, we first examined the global phenotypic changes in circulating CD8+ T cells after experimental infection of calves. T cell receptor repertoire together with transcriptomics and epigenomics analyses demonstrated an oligoclonal expansion of infected CD8+ T cells displaying effector and exhaustion gene signatures, including GZMA, GNLY, PD-1, and TOX2 expression. Then, among viral genes expressed in infected CD8+ T cells, we uncovered A10 that encodes a transmembrane signaling protein displaying multiple tyrosine residues, with predicted ITAM and SH3 motifs. Impaired A10 expression did not affect AlHV-1 replication in vitro but rendered AlHV-1 unable to induce MCF. Furthermore, A10 was phosphorylated in T lymphocytes in vitro and affected T cell signaling. Finally, while AlHV-1 mutants expressing mutated forms of A10 devoid of ITAM or SH3 motifs (or both) were able to induce MCF, a recombinant virus expressing a mutated form of A10 unable to phosphorylate its tyrosine residues resulted in the lack of MCF and protected against a wild-type virus challenge. Thus, we could characterize the nature of this γ-herpesvirus-induced PTCL-like disease and identify an essential mechanism explaining its development.

Cancer-associated mutations in VAV1 trigger variegated signaling outputs and T-cell lymphomagenesis.

Mutations in VAV1, a gene that encodes a multifunctional protein important for lymphocytes, are found at different frequencies in peripheral T-cell lymphoma (PTCL), non-small cell lung cancer, and other tumors. However, their pathobiological significance remains unsettled. After cataloguing 51 cancer-associated VAV1 mutations, we show here that they can be classified in five subtypes according to functional impact on the three main VAV1 signaling branches, GEF-dependent activation of RAC1, GEF-independent adaptor-like, and tumor suppressor functions. These mutations target new and previously established regulatory layers of the protein, leading to quantitative and qualitative changes in VAV1 signaling output. We also demonstrate that the most frequent VAV1 mutant subtype drives PTCL formation in mice. This process requires the concurrent engagement of two downstream signaling branches that promote the chronic activation and transformation of follicular helper T cells. Collectively, these data reveal the genetic constraints associated with the lymphomagenic potential of VAV1 mutant subsets, similarities with other PTCL driver genes, and potential therapeutic vulnerabilities.

Pyroptotic macrophages promote proliferation and chemotherapy resistance of peripheral T-cell lymphoma via TLR4 signaling pathway.

Peripheral T-cell lymphoma (PTCL) is a highly aggressive type of non-Hodgkin's lymphoma with a poor prognosis. Pyroptosis is a newly discovered procedural cell death mode, which has been implicated to occur in both tumor cells and immune cells. However, the occurrence and effect of pyroptosis on PTCL remain unclear. Here, we found that pyroptosis occurred in interstitial macrophages of PTCL rather than in tumor cells. In clinical specimens, macrophage pyroptosis was associated with a poor prognosis of PTCL. In vitro experiments and gene sequencing results showed that pyroptotic macrophages could upregulate the expression of TLR4 through secreting inflammatory cytokines IL-18. Upregulated TLR4 activated its downstream NF-κB anti-apoptotic signaling pathway, thus leading to malignant proliferation and chemotherapy resistance of tumor cells. Moreover, the expression of factors such as XIAP in the NF-κB anti-apoptotic pathway was downregulated after the knockdown of TLR4, and the malignant promotion effect of pyroptotic macrophages on PTCL cells was also reversed. Our findings revealed the mechanism of pyroptotic macrophages promoting the malignant biological behavior of PTCL and elucidated the key role of TLR4 in this process. In-depth analysis of this mechanism will contribute to understanding the regulatory effect of PTCL by the tumor microenvironment and providing new ideas for the clinical treatment of PTCL.

Single-cell landscape reveals the immune heterogeneity of bone marrow involvement in peripheral T-cell lymphoma.

The prognosis of patients with peripheral T-cell lymphoma (PTCL) depends on bone marrow involvement (BMI). The bone marrow (BM) tumor microenvironment in PTCL remains unclear. We performed single-cell RNA sequencing (scRNA-seq) on 11 fresh BM samples from patients with BMI to reveal the associations of immune landscape and genetic variations with the prognosis of PTCL patients. Compared with PTCL not otherwise specified (NOS), angioimmunoblastic T-cell lymphoma (AITL) had a higher number of T cells, lower number of lymphocytes, and greater inflammation. Immune heterogeneity in AITL is associated with prognosis. In particular, specific T-cell receptor (TCR) T cells are enriched in patients with good response to anti-CD30 therapy. We observed RhoA mutation-associated neoantigens. Chidamide-treated patients had a higher number of CD4+ regulatory cells and a better treatment response compared with other patients. In the nonresponder group, T-cell enrichment progressed to secondary B-cell enrichment and subsequently diffuse large B-cell lymphoma. Moreover, AITL patients with lymphoma-associated hemophagocytic syndrome had more T follicular helper (Tfh) cells with copy number variations in CHR5. To our knowledge, this study is the first to reveal the single-cell landscape of BM microenvironment heterogeneity in PTCL patients with BMI. scRNA-seq can be used to investigate the immune heterogeneity and genetic variations in AITL associated with prognosis.

Up-front autologous stem cell transplant in peripheral T-cell lymphoma patients achieving complete response after first-line treatment: A multicentre real-world analysis.

We conducted a retrospective, multicentre study to compare consolidation therapy with or without first-line autologous stem cell transplant (ASCT) for peripheral T-cell lymphoma (PTCL) patients in a real-world setting. We enrolled 347 PTCL patients who achieved complete response after first-line treatment. Of these, 257 received consolidation chemotherapy (non-ASCT group) and 90 received ASCT (ASCT group). Clinical outcomes were comparable between ASCT and non-ASCT groups. After propensity score matching, the 2-year cumulative incidence of treatment-related mortality and relapse remained similar between groups (1.9% vs. 2.0%, p = 0.985; 24.7% vs. 47.1%, p = 0.021). However, significant differences emerged in progression-free survival and overall survival probabilities. Within the T-cell lymphoma subgroup, ASCT patients exhibited favourable outcomes compared to non-ASCT patients: 2-year progression-free survival (73.4% vs. 50.8%, p = 0.024) and overall survival (92.1% vs. 73.5%, p = 0.021). Notably, no significant differences were observed for patients with NK/T-cell lymphoma. These real-world data suggest that up-front ASCT is a safe and effective consolidation option for PTCL patients in remission, particularly those with T-cell lymphoma.

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.

Clonal haematopoiesis: A common progenitor for cytotoxic peripheral T-cell lymphoma and angioimmunoblastic T-cell lymphoma.

Recent studies have shown that follicular helper T-cell lymphoma of angioimmunoblastic type (AITL), the most common nodal peripheral T-cell lymphoma (PTCL), frequently arises in a background of clonal haematopoiesis (CH), a preneoplastic condition affecting up to 40% of elderly individuals. Data on a potential CH association are limited for other PTCL. We report a unique patient who sequentially developed both cytotoxic PTCL, not otherwise specified and AITL with distinct T-cell receptor rearrangements but shared somatic mutations originating from the same CH clone, thus providing convincing evidence that CH can give rise to T-cell neoplasms of different lineage.

The fusion oncogene VAV1-MYO1F triggers aberrant T-cell receptor signaling in vivo and drives peripheral T-cell lymphoma in mice.

VAV1-MYO1F is a recently identified gain-of-function fusion protein of the proto-oncogene Vav guanine nucleotide exchange factor 1 (VAV1) that is recurrently detected in T-cell non-Hodgkin's lymphoma (T-NHL) patients. However, the pathophysiological functions of VAV1-MYO1F in lymphomagenesis are insufficiently defined. Therefore, we generated transgenic mouse models to conditionally express VAV1-MYO1F in T-cells in vivo. We demonstrate that VAV1-MYO1F triggers cell autonomous activation of T-cell signaling with an activation of the ERK, JNK, and AKT pathways. VAV1-MYO1F expression induces a T-cell activation phenotype with high surface expression of CD25, ICOS, CD44, PD-1, and decreased CD62L as well as aberrant T-cell differentiation, proliferation, and neoplastic transformation. Consequently, the VAV1-MYO1F expressing T-cells induce a malignant T lymphoproliferative disease with 100% penetrance in vivo that mimics key aspects of human peripheral T-cell lymphoma. These results demonstrate that the human T-cell oncogene VAV1-MYO1F is sufficient to trigger oncogenic T-cell signaling and neoplastic transformation, and moreover, it provides a new clinically relevant mouse model to explore the pathogenesis of and treatment concepts for human T-cell lymphoma.

Safety and effectiveness of mogamulizumab in relapsed or refractory CC chemokine receptor 4-positive peripheral T-cell lymphoma and relapsed or refractory cutaneous T-cell lymphoma: A post-marketing surveillance in Japan.

Mogamulizumab is a humanized antibody targeting CC chemokine receptor 4 (CCR4). This post-marketing surveillance was conducted in Japan as a regulatory requirement from 2014 to 2020 to ensure the safety and effectiveness of mogamulizumab in patients with relapsed or refractory (r/r) CCR4-positive peripheral T-cell lymphoma (PTCL) or r/r cutaneous T-cell lymphoma (CTCL). Safety and effectiveness data were collected for up to 31 weeks after treatment initiation. A total of 142 patients were registered; safety was evaluated in 136 patients. The median number of doses was 8.0 (range, 1-18). The main reasons for treatment termination were insufficient response (22.1%) and adverse events (13.2%). The frequency of any grade adverse drug reaction was 57.4%, including skin disorders (26.5%), infections and immune system disorders (16.2%), and infusion-related reactions (13.2%). Graft-versus-host disease, grade 2, developed in one of two patients who underwent allogeneic-hematopoietic stem cell transplantation after receiving mogamulizumab. Effectiveness was evaluated in 131 patients (103 with PTCL; 28 with CTCL). The best overall response rate was 45.8% (PTCL, 47.6%; CTCL, 39.3%). At week 31, the survival rate was 69.0% (95% confidence interval, 59.8%-76.5%) [PTCL, 64.4% (54.0%-73.0%); CTCL, 90.5% (67.0%-97.5%)]. Safety and effectiveness were comparable between patients <70 and ≥ 70 years old and between those with relapsed and refractory disease. The safety and effectiveness of mogamulizumab for PTCL and CTCL in the real world were comparable with the data reported in previous clinical trials. Clinical Trial Registration.

Clinical significance and predictive risk factors for event-free survival at 24 months in patients with PTCL, NOS.

Peripheral T cell lymphoma, not otherwise specified (PTCL, NOS), is a heterogeneous and aggressive type of non-Hodgkin's lymphoma with a bleak prognosis. This study was designed to assess the value of EFS24 as an alternative clinical endpoint and identify prognosis-related factors in PTCL, NOS. Patients diagnosed with PTCL, NOS were retrospectively collected and slides were reviewed by two hematopathologists. EFS was defined as the time from diagnosis to the occurrence of disease progression after initial treatment, retreatment, or death. Subsequent overall survival (OS) was defined from EFS24 or time of progression, if it occurred within 24 months, to the last follow-up or death. 97 cases with complete follow-up were selected. Approximately 66 patients (68.04%) failed to achieve ES24, with the median OS of 12.17 months, and 5-year OS rate of 15.17%. While patients who reached EFS24 had a median OS of 60.57 months and a 5-year OS rate of 68.77%. Multivariate Cox analysis indicated that bone marrow involvement and elevated ß2 Microglobulin (ß2-MG) were associated with a poor prognosis. B symptoms, extranodal involvement more than one site, and a high Ki67 index were significant factors in predicting the failure of EFS24. EFS24 can help stratify the subsequent outcomes of PTCL, NOS. Patients who achieve EFS24 have a favorable prognosis, although it does not reach that of the general population. On the other hand, patients who do not achieve EFS24 have an extremely poor prognosis. Therefore, EFS24 can be used for patient risk stratification, patient counseling, and study design.

Efficacy of chidamide maintenance therapy versus autologous stem cell transplantation versus observation as a post-remission choice in the survival of adult patients with peripheral T-cell lymphoma: Post hoc analysis of a prospective, multicenter, phase 2 study in China.

In this prospective, multicenter, Phase 2 clinical trial (NCT02987244), patients with peripheral T-cell lymphomas (PTCLs) who had responded to first-line chemotherapy with cyclophosphamide, doxorubicin or epirubicin, vincristine or vindesine, etoposide, and prednisone (Chi-CHOEP) were treated by autologous stem cell transplantation (ASCT) or with chidamide maintenance or observation. A total of 85 patients received one of the following interventions: ASCT (n = 15), chidamide maintenance (n = 44), and observation (n = 26). estimated 3 PFS and OS rates were 85.6%, 80.8%, and 49.4% (P = 0.001). The two-year OS rates were 85.6%, 80.8%, and 69.0% (P = 0.075).The ASCT and chidamide maintenance groups had significantly better progression-free survival (PFS) than the observation group (P = 0.001, and P = 0.01, respectively). The overall survival (OS) differed significantly between the chidamide maintenance group and the observation group ( P = 0.041). The multivariate and propensity score matching analyses for PFS revealed better outcomes in the subjects in the chidamide maintenance than observation groups (P = 0.02). The ASCT and chidamide maintenance groups had significant survival advantages over the observation group. In the post-remission stage of the untreated PTCL patients, single-agent chidamide maintenance demonstrated superior PFS and better OS than observation. Our findings highlight the potential benefit of chidamide in this patient subset, warranting further investigation through larger prospective trials. Clinical trial registration: clinicaltrial.gov, NCT02987244. Registered 8 December 2016, http://www.clinicaltrials.gov/ct2/show/NCT02987244 .

Immunophenotypic classification regarding prognosis in peripheral T cell lymphoma, NOS, and nodal T follicular helper T cell lymphoma, angioimmunoblastic-type.

This study aimed to determine the clinicopathological predictive factors of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS), and nodal T-follicular helper cell lymphoma, angioimmunoblastic-type (nTFH, AI-type). In this single-centered, retrospective study, medical records of 59 patients who were diagnosed with PTCL, NOS, or nTFH, AI-type from March 2007 to September 2022 were reviewed. The clinicopathological variables, including immunohistochemistry(IHC) subgroups, distinguishing TBX21 from the GATA3 subgroups were analyzed. Overall, 28 patients (75.7%) in the TBX21 group were PTCL, NOS. There were 9 (24.3%) patients in the GATA3 group. In univariable analyses, lymphoma subtype, age, and performance status were associated with progression-free survival (PFS), and overall survival (OS). In multivariable analyses, lymphoma subtype, and performance status were related to PFS and OS (P = 0.012, P < 0.001, P = 0.006, and P < 0.001, respectively). The GATA3 subgroup tended to have a worse prognosis in univariable analyses; however, it became more insignificant in multivariable when lymphoma subtype and performance status were adjusted (P = 0.065, P = 0.180, P = 0.972, and P = 0.265, respectively). The double-positive group showed variable prognoses of better PFS and worse OS. PD-1 and PD-L1 were associated with the EBV in situ hybridization (P = 0.027, and P = 0.005), and PD-1 was associated with CD30 expression (P = 0.043). This study demonstrated the potential of IHC classification to predict prognosis for PTCL, NOS, as well as nTFH AI-type, although further validation is necessary. Treatments targeting CD30, PD-1, and PD-L1 appear promising for lymphoma treatment.

Real-world treatment patterns, healthcare resource utilization and costs among patients with peripheral T-cell lymphoma.

Objective: To evaluate treatment patterns, healthcare resource utilization (HRU) and costs among peripheral T-cell lymphoma (PTCL) patients in the USA. Methods: A retrospective cohort study, using the IQVIA PharMetrics® Plus claims database from 1 April 2011 to 30 November 2021, identified PTCL patients receiving systemic treatments. Three mutually exclusive subcohorts were created based on line of therapy (LOT): 1LOT, 2LOT and ≥3LOT. Common treatment regimens, median time on treatment, all-cause and PTCL-related HRU and costs were estimated. Results: Among 189 PTCL patients identified, 61.9% had 1LOT, 21.7% had 2LOT and 16.4% had ≥3LOT. The most common treatment regimens in the 1LOT were CHOP/CHOP-like, CHOEP/CHOEP-like and brentuximab vedotin; monotherapies were most common in the 2LOT and ≥3LOT. All-cause and PTCL-related hospitalizations and prescriptions PPPM increased with increasing LOT. Nearly 70% of total treatment costs were PTCL related. Conclusion: Higher utilization of combination therapies in the 1LOT and monotherapies in subsequent LOTs were observed, alongside high PTCL-related costs.

Peripheral T-cell lymphomas (PTCL) are a rare and fast-growing form of blood cancer. About 8000­12,000 people in the USA are diagnosed with PTCL every year. As it is a rare disease and has many types, and there is a limited understanding of the patients who have PTCL and the treatments they receive in the real world. The purpose of this study was to evaluate how these patients are treated, what are they treated with and what are the costs of these treatments in the USA. The data collected on these patients was divided into three groups based upon the number of lines of treatment/therapy (LOT) they received: 1LOT, 2LOT and ≥3LOT. This study researched different treatments and their duration in each line of therapy. Among 189 PTCL patients included in the study, the average age of patients was 55 years and 62% were male. Among these patients, 62% had 1LOT, 22% had 2LOT and 16% had ≥3LOT. The most common treatments in the 1LOT were traditional chemotherapy regimens followed by targeted therapies: CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or CHOP-like, CHOEP (cyclophosphamide, doxorubicin, vincristine, etoposide and prednisone) or CHOEP-like, and brentuximab vedotin. Treatment regimens with only one drug were most common in the 2LOT and ≥3LOT. The total cost of PTCL treatment in the USA is very high; 70% of this cost is related to their treatment with various drugs. More research is needed to better understand the treatment and cost of this rare cancer.

Standardization of CD30 immunohistochemistry staining among three automated immunostaining platforms.

The identification of CD30 expression by immunohistochemistry is essential for the treatment of lymphomas using an antibody-drug conjugate targeting CD30. However, no standardized protocol for CD30 staining has been available. In this study, we compared three common automated immunostaining platforms {Bond III (B III), Dako Omnis (DO) and Ventana BenchMark ULTRA (VBMU)}. A primary antibody for CD30, the Ber-H2 clone, was diluted 50- to 400-fold for B III and DO, and ready-to-use antibody was used for VBMU. An enhancement step using a linker was introduced in all protocols. First, several candidate dilutions were selected for each platform by staining six cases. These candidate conditions were then confirmed with 60 cases of various types of peripheral T-cell lymphomas (PTCLs). The concordance rates of CD30 expression among platforms differed depending on cutoff values and antibody dilutions, except for anaplastic large cell lymphoma. The concordance rates among three platforms in the evaluation of "positive" or "negative" were 100% and 97% when the cutoff values were 1% and 10% respectively, if using 400-diluted antibody in B III and 100-diluted antibody in DO. This study demonstrated the feasibility of equalizing CD30 staining of PTCLs among different platforms by adjusting protocols.

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.

Clinical and Real-World Effectiveness of Mogamulizumab: A Narrative Review.

Mogamulizumab (MOG) is an antibody targeting the CCR4 receptor, authorized for relapsed or refractory peripheral T-cell (PTCL) and cutaneous T-cell lymphomas (CTCL). Its adoption in guidelines and endorsement by FDA and EMA established it as a systemic treatment, especially for advanced disease stages due to its comparatively lower toxicity. Clinical trials and real-world evidence have underscored its efficacy in advanced CTCLs, including mycosis fungoides and Sézary syndrome; PTCLs; and adult T-cell leukemia/lymphoma (ATLL), showcasing positive outcomes. Notably, the drug has demonstrated significant response rates, disease stability, and extended periods of progression-free survival, suggesting its applicability in cases with multiple treatment lines. Its safety profile is generally manageable, with adverse events (AEs) primarily related to the skin, infusion-related reactions, drug eruptions, autoimmune diseases, and skin disorders. The latter seem to appear as CCR4 can promote the skin-specific homing of lymphocytes, and MOG is directed against this receptor. While combination with immunostimulatory agents like interferon alpha and interleukin 12 has shown promising results, caution is urged when combining with PD1 inhibitors due to the heightened risk of immune-mediated AEs. The introduction of MOG as a systemic treatment implies a significant advancement in managing these diseases, supported by its favorable safety profile and complementary mechanisms.

Nodal T follicular helper cell lymphoma with aberrant CD20 expression and monoclonal TCR, IG rearrangements secondary to Classical Hodgkin Lymphoma: a case report.

Classical Hodgkin Lymphoma (CHL) is a rare malignant neoplasm of the lymphatic system. While CHL typically responds well to conventional treatments, some cases may experience relapse to other subtypes, with the development of secondary peripheral T-cell lymphoma (PTCL) being relatively uncommon. Herein, we report a rare case of nodal T follicular helper cell lymphomas,nos (nTFHL-NOS) secondary to CHL, accompanied by aberrant CD20 expression and clonal rearrangements of T-cell receptor (TCR) and immunoglobulin (IG). A 74-year-old male, was diagnosed with CHL, leaning toward the mixed cell type, 6 years ago. He received six cycles of the Adriamycin, Bleomycin, Vinblastine, Dacarbazine (ABVD) regimen, achieving complete clinical remission. The patient was admitted to our hospital due to the appearance of multiple skin nodules 66 months later. Histopathological analysis revealed nTFHL-NOS, with aberrant CD20 expression and clonal rearrangements of TCR and IG. The patient underwent two cycles of chemotherapy with brentuximab vedotin and the Gemcitabine-Oxaliplatin (G-mox) regimen, resulting in a reduction of the skin lesions to 2 cm × 1 cm. We discuss this rare case and review related literature.

Peripheral T-cell lymphoma with a T follicular-helper phenotype: A different entity? Results of the Spanish Real-T study.

Nodal peripheral T-cell lymphoma (PTCL) with a T follicular helper phenotype (PTCL-TFH) is a new type of PTCL. We aimed to define its clinical characteristics and prognosis compared to PTCL not otherwise specified (PTCL-NOS) and angioimmunoblastic T-cell lymphoma (AITL). This retrospective observational study included 175 patients diagnosed with PTCL between 2008 and 2013 in 13 Spanish sites. Patient diagnosis was centrally reviewed, and patients were reclassified according to the World Health Organization (WHO) 2016 criteria: 21 patients as PTCL-NOS, 55 as AITL and 23 as PTCL-TFH. Median follow-up was 56.07 months (95% CI 38.7-73.4). Progression-free survival (PFS) and overall survival (OS) were significantly higher in patients with PTCL-TFH than in those with PTCL-NOS and AITL (PFS, 24.6 months vs. 4.6 and 7.8 months, respectively, p = 0.002; OS, 52.6 months vs. 10.0 and 19.3 months, respectively, p < 0.001). Histological diagnosis maintained an independent influence on both PFS (hazard ratio [HR] 4.1 vs. PTCL-NOS, p = 0.008; HR 2.6 vs. AITL, p = 0.047) and OS (HR 5.7 vs. PTCL-NOS, p = 0.004; HR 2.6 vs. AITL, p = 0.096), regardless of the International Prognostic Index. These results suggest that PTCL-TFH could have more favourable features and prognosis than the other PTCL subtypes, although larger series are needed to corroborate these findings.

Mutation profiling, tumour burden assessment, outcome prediction and disease monitoring by circulating tumour DNA in peripheral T-cell lymphoma.

In this prospective study, we aimed to evaluate the utility of circulating tumour DNA (ctDNA) in peripheral T-cell lymphomas (PTCLs). Plasma cell-free DNA (cfDNA) was obtained, and the mutational profile was assessed in 47 patients with newly diagnosed mature T- and NK-cell lymphoma. To validate the mutations detected in cfDNA, paired tumour tissue samples were available for 36 patients. Targeted next-generation sequencing was performed. A total of 279 somatic mutations involving 149 genes were identified in the 47 cfDNA samples. The overall sensitivity of plasma cfDNA in discovering biopsy-confirmed mutations was 73.9% with a specificity of 99.6%. When we considered only mutations with variant allele frequency >5% in the tumour biopsy, the sensitivity increased to 81.9%. Pretreatment ctDNA concentration and the number of mutations were highly correlated with tumour burden indicators including lactate dehydrogenase, Ann Arbor stage and International Prognostic Index score. Patients with high ctDNA level (>1.9 log ng/mL) had significantly lower overall response rates, inferior 1-year progression-free survival and overall survival rates than those with low level. Longitudinal analysis of ctDNA showed a strong agreement between ctDNA dynamics and the radiographic response. In conclusion, our study demonstrates that ctDNA may serve as a promising tool for mutational profiling, tumour burden assessment, outcome prediction and disease monitoring in PTCLs.