Search Results (116)

Background/Objectives: Advanced-stage mycosis fungoides (MF) and Sézary syndrome (SS) are aggressive forms of cutaneous T-cell lymphoma (CTCL) for which treatment options are limited and prognosis is poor. Brentuximab vedotin (BV), an anti-CD30 antibody–drug conjugate, has demonstrated high response rates in patients with CD30 expression ≥ 10%. However, data on its efficacy in cases with low CD30 expression (<10%) remain scarce. Methods: This retrospective analysis evaluated the real-world efficacy of BV in patients with advanced-stage MF/SS and low CD30 expression. A retrospective analysis was conducted on 32 patients across 11 German CTCL expert centers. All patients had advanced-stage MF or SS with CD30 expression < 10% and received BV at the standard dose. Treatment response was assessed using EORTC-ISCL criteria. Results: All patients had received prior systemic therapies (median: 3) with 36% having undergone prior mono- or polychemotherapy. The study population included 30 MF (stage IIB) and two SS cases. The overall response rate (ORR) in this population was 53.1% (17/32). A complete response (CR) was achieved in 12.5% (4/32), a partial response (PR) was achieved in 40.6% (13/32), stable disease (SD) was seen in 18.8% (6/32), and progressive disease (PD) was seen in 28.1% (9/32). The median progression-free survival (PFS) was 4.0 months (arithmetic mean: 6.38; range: 0.5–15.5), and the median time to next treatment (TTNT) was 7.25 months (arithmetic mean: 7.30; range: 2.00–15.5). Conclusions: BV demonstrated encouraging activity in heavily pretreated advanced MF/SS with low CD30 expression, achieving an ORR comparable to that observed in patients with higher CD30 levels. While response rates were similar, PFS was shorter. These findings suggest that BV remains a potential therapeutic option in this patient population and merits further prospective investigation. Full article

Cutaneous lymphomas are a heterogeneous group of extranodal non-Hodgkin lymphomas with distinct clinical and biological features, broadly classified into cutaneous T-cell lymphomas (CTCL) and cutaneous B-cell lymphomas (CBCL). With improved survival due to early detection and therapeutic advances, the emergence of second primary malignancies (SPMs) has become a clinical concern. SPMs, defined as new, distinct malignant neoplasms arising synchronously or metachronously with the index cancer, can significantly impair prognosis and quality of life. In this narrative review, we meticulously examine the current literature, to synthesize evidence on SPMs’ incidence and risk factors in patients with primary cutaneous lymphomas. Evidence from population-based and institutional studies consistently demonstrates elevated risks of hematologic and solid tumors in CTCL. By contrast, data on CBCL remain limited, though recent population-based analyses suggest increased risks of certain hematologic malignancies and solid tumors. We further propose development mechanisms for SPMs, including treatment-related mutagenesis, shared genetic susceptibilities, chronic antigenic stimulation, and immune dysregulation. Lastly, we highlight the clinical implications of these findings, underscoring the need for vigilant surveillance, patient education, and tailored screening strategies. Future research should prioritize large-scale, prospective, and molecularly integrated studies to refine risk stratification and guide personalized survivorship care of this vulnerable population. Full article

Introduction: Primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (PCAETL) is a rare and highly aggressive subtype of cutaneous T-cell lymphoma (CTCL), accounting for less than 1% of CTCL cases. It is defined by CD8+ cytotoxic T-cell proliferation with marked epidermotropism, necrosis, and a high proliferative index. Clinically, it presents as ulcerated or necrotic lesions with rapid progression and poor response to conventional therapies. Aims: To describe a fatal case of PCAETL in a young adult female, emphasizing the diagnostic challenges, clinical progression, histopathological features, and treatment limitations. Case Presentation: A 41-year-old Venezuelan woman presented with a 10-month history of disseminated papules and nodules initially misdiagnosed as Hansen’s disease. After her arrival in Ecuador, she was re-evaluated and found to have generalized dermatosis with ulcerated nodules and tumors. Histopathological examination revealed atypical epidermotropic CD8+ T-cell infiltration with extensive necrosis. Immunohistochemistry demonstrated strong positivity for CD3, CD5, and CD8, and a Ki-67 index of 80%, confirming the diagnosis of PCAETL. The patient received methotrexate with partial response but experienced disease relapse during second-line etoposide therapy. She developed febrile neutropenia and died five months after diagnosis. Conclusions: This case highlights the rarity, diagnostic complexity, and aggressive nature of PCAETL. Early recognition and clinico-pathological correlation are essential for timely diagnosis. However, therapeutic options remain limited, and outcomes are poor despite systemic chemotherapy. Further research into targeted and personalized therapies is urgently needed to improve survival in this devastating disease. Full article

Cutaneous T-Cell Lymphomas (CTCL) are a heterogenous group of T-cell malignancies in the skin and have poor treatment outcomes in advanced stages. CD5, a surface glycoprotein expressed on most mature T cells, has emerged as a promising target for chimeric antigen receptor (CAR) T-cell therapy in systemic T-cell lymphomas. However, its expression profile in CTCL and relevance for targeted therapy remain unclear. Notably, in CTCL, the cell surface expression of receptors, such as CD7 and CD26, tends to become downregulated on the surfaces of malignant T cells In this study, we analyzed single-cell RNA sequencing (scRNA-seq) data from patients at two institutions with mycosis fungoides (MF), the most common subtype of CTCL with a predominantly CD4 phenotype. We utilized 5 patch/plaque MF skin biopsies (majority from early-stage patients), 8 MF tumor biopsies (all from advanced-stage patients), and 8 healthy control biopsies to evaluate lesion-specific CD5 gene expression on CD4 T cells. We found that CD5 was significantly increased in malignant MF CD4 T cells compared to healthy control CD4 T cells (21.1% of MF CD4 T cells expressed CD5 vs. 5.2% of healthy control CD4 T cells, respectively). In subgroup analysis, patch/plaque stage MF biopsies showed higher expression of CD5 in CD4 T cells than tumor stage MF biopsies. Notably, 94.3% of malignant CD4⁺ T cells in tumor stage MF lesions exhibited complete CD5 loss compared to only 76.6% in patch-plaque MF lesions, suggesting antigen escape in tumor stage disease. These findings demonstrate that CD5 expression in CTCL is dynamic and varies based on lesion type. Our work suggests CD5 may be a viable therapeutic target in MF with patch/plaque presentations but may not be as effective in advanced stages of MF with tumor presentations. This work informs CD5 gene expression in MF based on clinical lesion type and further information is needed to clarify clinical implications as a future therapeutic target. Full article

Background/Objectives: High-frequency ultrasonography (HFUS) has gained increasing attention in dermatology as a non-invasive imaging technique capable of visualizing cutaneous structures with high resolution. In cutaneous T-cell lymphomas (CTCL), including mycosis fungoides (MF)/Sézary syndrome (SS), HFUS may provide an objective method for assessing disease activity and monitoring treatment response. This study aimed to evaluate the clinical utility of HFUS in detecting therapy-induced changes in subepidermal low-echogenic band (SLEB) thickness. Methods: We conducted a prospective, single-center study between May 2021 and May 2025. Thirty-three patients with histologically confirmed MF (n = 31) or SS (n = 2) underwent HFUS at baseline and after 4–8 weeks of treatment. SLEB thickness was measured before (E1) and after early treatment (E2). Patients received systemic agents, phototherapy, or topical regimens. Statistical analysis included mixed-model ANOVA with repeated measures to assess SLEB changes, and post hoc tests were applied to explore the influence of therapy type, age, and gender. Results: Among 31 evaluable patients with MF, HFUS revealed a significant reduction in SLEB thickness after treatment (0.90 ± 1.10 mm vs. 0.69 ± 0.89 mm; F(1,29) = 8.88, p = 0.006, η² = 0.23). The type of early therapy (systemic vs. topical) did not significantly affect outcomes (p = 0.452). Age emerged as a relevant factor: patients ≥ 66 years exhibited higher baseline SLEB values and a significant reduction post-treatment (p < 0.001), whereas no comparable effect was observed in younger patients. Gender did not significantly influence SLEB changes. Conclusions: HFUS is a sensitive and clinically applicable imaging tool for monitoring treatment response in MF/SS. Reductions in SLEB thickness were observed across therapeutic modalities and aligned with early clinical improvement. HFUS may serve as a valuable adjunct to standard clinical and histopathological evaluation in the routine management of MF/SS. Full article

Background: Mycosis fungoides (MF) is a rare cutaneous T-cell lymphoma (CTCL) that presents clinically on the skin as patches, plaques, or tumors. MF often mimics benign inflammatory conditions which leads to difficult and delayed diagnosis, worsening prognosis despite available treatment options. This study seeks to improve diagnosis and identify potential therapeutic targets by better characterizing MF’s genetic landscape using the AACR Project GENIE dataset. Methods: Retrospective analysis of MF cases was conducted using the AACR Project GENIE database accessed from cBioPortal (v17.0-public) on 5 June 2025. Data analysis included identifying recurrent somatic mutations, assessing patterns of mutation co-occurrence and mutual exclusivity using non-parametric tests with Benjamini–Hochberg False Discovery Rate (FDR) correction, and examining enrichment of specific mutations based on sex and race, with significance of p < 0.05. Results: Recurrent alterations included FAT1 (28.2%), KMT2D (19.2%), TP53 (13.5%), JAK3 (11.5%), and SETBP1 (11.5%), highlighting the role of Wnt signaling, epigenetic dysregulation, the p53 pathway, and JAK/STAT signaling in MF pathogenesis. Mutations with significant co-occurrence and enrichment in White, Black, and Asian populations were identified. Conclusions: The findings of this study provide a comprehensive understanding of MF’s molecular profile. The discovery of commonly mutated pathways (Wnt, p53, JAK/STAT, and epigenetic regulators) suggests potential targets for the development of future therapies. Furthermore, the enrichment of certain mutations based on race and patterns of alteration co-occurrence offer possibilities for patient-tailored treatment approaches. Full article

Cutaneous T-cell Lymphomas (CTCLs) are a heterogeneous group of non-Hodgkin lymphomas that currently have an incompletely understood pathophysiology and several challenges in both diagnosis and management. Single-cell RNA sequencing (scRNA-seq) is a powerful tool that enables the analysis of gene expression at the individual-cell level, revealing cellular heterogeneity and a complex tumor microenvironment. As single-cell RNA sequencing has become increasingly utilized, we aimed to provide an update on recent notable applications of single-cell RNA sequencing in CTCL and their findings. The included studies highlight the intricate network of interactions in the tumor microenvironment that contributes to tumorigenesis. While CTCL is notoriously heterogeneous, our results identify key markers that prove promising for diagnosis, prognostication, and therapeutic targets. Full article

Primary cutaneous lymphomas (PCLs), including cutaneous T-cell lymphomas (CTCL) and primary cutaneous B-cell lymphomas (PCBCL), are a diverse group of non-Hodgkin lymphomas that primarily affect the skin. Radiotherapy (RT) plays a pivotal role in the treatment of these lymphomas, particularly for localized disease, due to its ability to deliver precise, skin-directed treatment. Mycosis fungoides (MF) and Sézary syndrome (SS), the most common subtypes of CTCL, often require skin-directed therapies such as electron beam therapy and superficial brachytherapy to manage localized lesions. Electron beam therapy, including total skin electron beam therapy (TSEBT), has been utilized for decades, offering high response rates but with the risk of cumulative skin toxicity. Recently, low-dose radiotherapy (LDRT) has gained attention as an effective alternative that reduces toxicity while maintaining durable responses. Superficial brachytherapy is another modality that delivers radiation through custom molds, allowing for homogeneous dosing over complex anatomical areas like the face. Both teleradiotherapy and brachytherapy have demonstrated high complete response rates, with low recurrence rates observed when higher doses are used. In the context of primary cutaneous B-cell lymphomas, such as primary cutaneous marginal zone lymphoma (PCMZL) and primary cutaneous follicle center lymphoma (PCFCL), radiotherapy also offers excellent local control, particularly for indolent subtypes. However, more aggressive subtypes, such as diffuse large B-cell lymphoma, leg type (PCDLBCL-LT), may require systemic therapies in addition to radiation. Overall, teleradiotherapy and brachytherapy are essential components of the therapeutic arsenal for primary cutaneous lymphomas, offering effective disease control with manageable toxicity, while ongoing research focuses on optimizing treatment strategies and exploring novel combinations with systemic therapies. Full article

Background/Objectives: We examined the in vivo effects of successive treatments with the histone deacetylase (HDAC) inhibitor romidepsin in patients with cutaneous T-cell lymphoma (CTCL), using changes in gene expression in peripheral blood mononuclear cells (PBMCs). Methods: Exploiting data from a highly responsive CTCL patient through 12 months of treatment, we identified a malignant cell predictor (MCP), a gene signature associated with the diminishing numbers of circulating malignant cells. Results: The MCP was successfully validated in the patient’s relapse sample 9 months after treatment was terminated and via an independent set of CTCL patient samples. Conclusions: The MCP set of genes contained novel CTCL markers, including membrane-associated proteins not normally expressed in lymphocytes. A subclass of those markers was also detectable in residual malignant cells undetected by flow cytometry in remission samples from a patient who relapsed 10 months later. We identified a subset of transcriptional regulators, miRNAs and methylation patterns associated with the effect of progressive treatments revealing potential mechanisms of transcriptional dysregulation and functional effects in the malignant cells. We demonstrate a role for transcriptional activator HLF, over-expressed in malignant cells, and downregulated transcriptional-suppressor and immune-modulator NFIL3, as regulators of CTCL-specific genes. Full article

Mogamulizumab is a humanized monoclonal antibody that targets C-C chemokine receptor 4 (CCR4) present on certain T cells in lymphomas and leukemias. This antibody-based therapy has demonstrated efficacy in treating various cutaneous T cell lymphomas (CTCLs), including mycosis fungoides and Sézary syndrome, through the depletion of CCR4-expressing T cells by antibody-dependent cellular cytotoxicity (ADCC). However, the precise epitope and binding mode of mogamulizumab responsible for its augmented ADCC activity remain undisclosed. Here, X-ray crystallographic studies of mogamulizumab in complex with a 28-residue N-terminal peptide indicated that SIYSNYYLYES (residues 14–24) would constitute the antibody epitope. Another high-resolution structure, using a short core peptide of these 11 residues, has elucidated unambiguous electron density for the bound peptide, confirming consistent binding for both peptides. This linear epitope is located in the membrane-proximal region of CCR4, facilitating the Fc-mediated effector functions, including ADCC. The structures also provide insights into the molecular basis for the resistance of the CCR4 L21V variant to mogamulizumab, which is due to a lack of structural complementarity with mogamulizumab binding. Understanding the structural basis for the mechanism of action of mogamulizumab is crucial for optimizing anti-CCR4 therapeutics to improve treatment outcomes for patients with these challenging diseases. Full article

Non-Hodgkin lymphomas (NHLs) encompass a diverse group of neoplasms arising from the clonal proliferation of B-cell progenitors, T-cell progenitors, mature B-cells, mature T-cells, and natural killer (NK) cells. These malignancies account for over 90% of lymphoid neoplasms. The link between the gut microbiome and neoplasms has been extensively studied in recent years. Growing evidence suggests that the gut microbiome may be involved not only in the development of the disease, but also in modulating the efficacy of implemented therapies. In this review, we summarize the current knowledge on the potential involvement of the gut microbiome in the development of diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mucosa-associated lymphoid tissue (MALT) lymphoma, and NK/T-cell lymphoma, including cutaneous T-cell lymphoma (CTCL). Moreover, we discuss the relationship between gut microbiome changes before and after treatment and their association with treatment outcomes, focusing on chemotherapy and CAR T-cell therapy. Full article

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most prevalent forms of cutaneous T-cell lymphoma (CTCL) and are characterized by the proliferation of CD4⁺ T-helper cells. The pathogenesis of CTCLs involves a critical interaction between neoplastic cells and the tumor microenvironment. This interaction is driven not only by cytokines but also by surface proteins that mediate cell–cell contact. One such protein, OX40 (also known as CD134), is a member of the TNF receptor superfamily and serves as an induced costimulatory molecule that facilitates the interaction between T-cells and antigen-presenting cells. In this narrative review, we explore the literature surrounding the OX40–OX40L interaction in CTCLs, highlighting its pathogenic and prognostic significance. Additionally, we compare the expression and function of OX40–OX40L in chronic inflammatory skin diseases, such as atopic dermatitis and psoriasis, with their role in CTCLs. Finally, we provide an overview of the current state of therapeutic research, discussing the potential of targeting the OX40–OX40L axis in CTCL treatment. Full article

Background/Objectives: Primary cutaneous lymphomas (CLs) are a group of skin-limited lymphoproliferative disorders, including cutaneous T-cell (CTCLs) and B-cell lymphomas (CBCLs). Photodynamic therapy (PDT), a non-invasive, light-activated treatment, has gained attention as a skin-directed therapy for early-stage CLs due to its selectivity and favorable safety profile. This systematic review evaluates the current evidence on the clinical use of PDT in managing CLs. Methods: A systematic literature search was conducted in PubMed, Scopus, and Embase through 1 September 2024 following PRISMA guidelines. Search terms included “primary cutaneous skin lymphoma”, “CTCL”, “CBCL”, “mycosis fungoides”, “lymphomatoid papulosis”, and “photodynamic therapy”. After screening 1033 records, 30 studies were included. Data were extracted and categorized by lymphoma subtype and clinical outcomes. Results: Of the included studies, 23 focused on mycosis fungoides (MF), 5 on lymphomatoid papulosis (LyP), and 2 on CBCL. PDT demonstrated notable clinical efficacy in early-stage and localized disease, particularly MF, using methyl aminolevulinate (MAL) or 5-aminolevulinic acid (5-ALA) as photosensitizers. Adjunctive techniques like microneedling and laser-assisted delivery improved treatment outcomes. PDT was generally well tolerated, with mild, transient side effects; rare complications such as localized neuropathy were reported. Conclusions: PDT is a promising, non-invasive treatment for early-stage CLs, especially MF and indolent CBCL variants. While current evidence supports its safety and effectiveness, further comparative and prospective studies are needed to refine protocols, evaluate long-term efficacy, and compare different photosensitizers. Full article

Recent studies have identified N6-methyladenosine (m6A) RNA methylation as a key regulatory mechanism in tumor progression. This study aimed to elucidate the biological function and clinical relevance of the m6A methyltransferase METTL3 in cutaneous T-cell lymphoma (CTCL). Our findings demonstrated that METTL3 expression is upregulated in CTCL, and its knockdown suppresses CTCL progression. Mechanistically, the downregulation of METTL3-mediated m6A modification on ARHGEF12 mRNA accelerated its degradation, a process that is closely associated with tumor behaviors. These results suggest that METTL3 may serve as a potential therapeutic target in CTCL. Full article

Background/Objectives: Brentuximab vedotin (BV) has been shown to be effective in the treatment of classical Hodgkin’s lymphoma (cHL), systemic anaplastic large cell lymphoma (sALCL), and CD30-positive cutaneous T-cell lymphoma (CTCL). This study aimed to evaluate the effectiveness and safety of BV retreatment in patients with relapsed/refractory cHL, sALCL, and CD30-positive CTCL. Methods: This multicenter, non-interventional, retrospective medical chart review study analyzed medical records from 43 patients retreated with BV in Spain. Patients were included if they had relapsed or refractory cHL, sALCL, or CD30-positive CTCL and were previously treated with BV. Demographic characteristics, disease stage, response to treatment, survival outcomes, and adverse events were analyzed. Results: The study population included 16 patients with cHL, 13 with sALCL, and 14 with CTCL. The majority were male (58.1%) with a mean age of 46.2 years and baseline ECOG scores of 0–1. Among cHL and sALCL patients, disease stage, according to the Ann Arbor classification, ranged from I to IVB, while in CTCL, EORTC clinical stages ranged from IA to IVB. The overall response rate to BV retreatment was 76.7%, with the highest response observed in sALCL (92.3%). Complete remission was achieved in 60.5% of patients. Median progression-free survival was 25.4 months, and overall survival reached 50 months. Treatment failure occurred in 37.2% of patients. BV was generally well tolerated, with peripheral neuropathy being the most frequently reported adverse event. Conclusions: The BELIEVE study is the largest study to date demonstrating that retreatment with BV is an effective and well-tolerated option for patients with relapsed or refractory CD30-positive malignancies. Full article