Radiotherapy Eradicates Malignant T Cells and Is Associated with Improved Survival in Early-Stage Mycosis Fungoides

Advances in the pharmacological management of cutaneous T-cell lymphoma

INTRODUCTION

Current treatment guidelines for cutaneous T cell lymphoma (CTCL) advocate a stage-driven approach, considering clinical presentation, symptom burden, and patient comorbidities. Therapy selection hinges on factors like disease subtype, severity, and treatment availability. The primary goal is to enhance the quality of life by mitigating symptoms, as achieving lasting complete remission is infrequent.

AREAS COVERED

Over the past decade (2013-2023), the therapeutic landscape of CTCL has experienced substantial transformation with the introduction of innovative therapies. This review explores the main pivotal developments in traditional treatment schedules and recently introduced drugs, aiming to offer clinicians and researchers a thorough perspective on the decade's progress in the field.

EXPERT OPINION

Despite the progress made in CTCL therapeutics, ranging from topical chemotherapeutics to immunomodulatory agents, several unmet needs persist. Firstly, there is a pressing need for the incorporation of readily available predictors for treatment response, encompassing clinical, pathological, and molecular features. Secondly, a more profound comprehension of the tumor microenvironment is imperative to optimize the landscape of targetable molecules. Lastly, the undertaking of studies on combination regimens should be encouraged as it enhances therapy efficacies by synergistically combining agents with diverse modes of action.

Immunobiology and treatment of cutaneous T-cell lymphoma

INTRODUCTION

Primary cutaneous T cell lymphomas (CTCL) are a heterogenous group of non-Hodgkin lymphomas derived from skin-homing T cells. These include mycosis fungoides and its leukemic variant Sezary syndrome, as well as the CD30+ lymphoproliferative disorders.

AREAS COVERED

In this review, we provide a summary of the current literature on CTCL, with a focus on the immunopathogenesis and treatment of mycosis fungoides and Sezary syndrome.

EXPERT OPINION

Recent advances in immunology have provided new insights into the biology of malignant T cells. This in turn has led to the development of new therapies that modulate the immune system to facilitate tumor clearance or target specific aspects of tumor biology.

Immunosequencing applications in cutaneous T-cell lymphoma

Immunosequencing has emerged as a newer clinical test for assessment of T-cell clonality in the blood and skin of cutaneous T-cell lymphoma (CTCL) patients. Utilization of immunosequencing, also known as high-throughput sequencing of the T-cell receptor (HTS-TCR), enables identification and quantification of the precise genetic signature of dominant T-cell clones. Although immunosequencing is more sensitive than commonly used methods such as polymerase chain reaction (PCR) paired with capillary electrophoresis or flow cytometry, it remains underutilized for CTCL management. Nonetheless, incorporation of HTS-TCR in clinical practice offers distinct advantages compared to other molecular analyses that may improve diagnostic evaluation, prognostication, and disease monitoring in CTCL. The objective of this comprehensive review is to provide a thorough explanation of the application of immunosequencing in the context of CTCL. We describe the significance of T-cell clonality and the methods used to detect it, including a detailed comparison between PCR paired with capillary electrophoresis and HTS-TCR. The utilization of immunosequencing in the blood and skin of CTCL patients is discussed in depth, specifically outlining how HTS-TCR can assist in diagnosing CTCL, predicting outcomes, and tracking disease progression. Finally, we address the potential applications of immunosequencing in clinical management and research as well as the novel challenges it presents.

EORTC consensus recommendations for the treatment of mycosis fungoides/Sézary syndrome - Update 2023

On behalf of the EORTC Cutaneous Lymphoma Tumours Group (EORTC-CLTG) and following up on earlier versions published in 2006 and 2017 this document provides an updated standard for the treatment of mycosis fungoides and Sézary syndrome (MF/SS). It considers recent relevant publications and treatment options introduced into clinical practice after 2017. Consensus was established among the authors through a series of consecutive consultations in writing and a round of discussion. Treatment options are assigned to each disease stage and, whenever possible and clinically useful, separated into first- and second line options annotated with levels of evidence. Major changes to the previous version include the incorporation of chlormethine, brentuximab vedotin, and mogamulizumab, recommendations on the use of pegylated interferon α (after withdrawal of recombinant unpegylated interferons), and the addition of paragraphs on supportive therapy and on the care of older patients. Still, skin-directed therapies are the most appropriate option for early-stage MF and most patients have a normal life expectancy but may suffer morbidity and impaired quality of life. In advanced disease treatment options have expanded recently. Most patients receive multiple consecutive therapies with treatments often having a relatively short duration of response. For those patients prognosis is still poor and only for a highly selected subset long term remission can be achieved with allogeneic stem cell transplantation. Understanding of the disease, its epidemiology and clinical course, and its most appropriate management are gradually advancing, and there is well-founded hope that this will lead to further improvements in the care of patients with MF/SS.

What Is New in Cutaneous T Cell Lymphoma?

PURPOSE OF REVIEW

This review focuses on updates in prognosis, pathogenesis, and treatment of cutaneous T cell lymphoma (CTCL).

RECENT FINDINGS

Cohort studies indicate imaging may be necessary in early-stage CTCL. Risk factors for progression of CTCL have been identified. Interactions between malignant cells and the tumor microenvironment (TME) and the skin microbiome advance the understanding of pathogenesis and tumor cell dissemination. Studies support a hypothesis of circulating malignant tumor cells. MicroRNA (miR) influence tumor progression and prognosis; the IL22-STAT3-CCL20 cascade may be a novel target. IL-4, IL-5, and IL-31 cytokines are relevant for pruritus and could be targets for therapeutic interventions. Systemic therapies, such as JAK inhibitors, targeted antibodies, and checkpoint inhibitors, show promise in advanced stages. Allogenic hematopoietic stem cell transplantation provides a potential curative option for patients. Further investigations of prognosis and translational research are necessary to improve stratification of patients for treatment.

Molecular techniques drive cutting edge advancements in management of cutaneous T cell lymphoma

Cutaneous 5T cell lymphoma (CTCL), characterized by malignant T cells infiltrating the skin with potential for dissemination, remains a challenging disease to diagnose and treat due to disease heterogeneity, treatment resistance, and lack of effective and standardized diagnostic and prognostic clinical tools. Currently, diagnosis of CTCL practically relies on clinical presentation, histopathology, and immunohistochemistry. These methods are collectively fraught with limitations in sensitivity and specificity. Fortunately, recent advances in flow cytometry, polymerase chain reaction, high throughput sequencing, and other molecular techniques have shown promise in improving diagnosis and treatment of CTCL. Examples of these advances include T cell receptor clonotyping via sequencing to detect CTCL earlier in the disease course and single-cell RNA sequencing to identify gene expression patterns that commonly drive CTCL pathogenesis. Experience with these techniques has afforded novel insights which may translate into enhanced diagnostic and therapeutic approaches for CTCL.

Allogeneic transplantation in advanced cutaneous T-cell lymphomas (CUTALLO): a propensity score matched controlled prospective study

BACKGROUND

Advanced-stage cutaneous T-cell lymphomas (CTCLs) are rare, usually refractory, and fatal diseases. Case series have suggested that allogeneic haematopoietic stem cell transplantation (HSCT) might improve the prognosis of advanced-stage CTCLs. The objective of this study was to investigate the effect of allogeneic HSCT compared with non-HSCT therapy on the outcome of individuals with advanced-stage CTCLs.

METHODS

In this prospective, multicentre, matched controlled trial, conducted at 30 hospitals, participants with advanced CTCLs were allocated treatment: if they had an available compatible related donor they were assigned to allogeneic HSCT, or if not they were allocated to non-allogeneic HSCT therapy. Key inclusion criteria were participants aged 18-70 years, with advanced stage mycosis fungoides or Sézary syndrome, and at least one poor prognostic criteria. Participants were excluded if they were not in complete or partial remission of the disease. Propensity score 1:1 matching with replacement (ie, that each participant treated with HSCT was matched to the participant with the closest propensity score treated with non-HSCT therapy, even if they had already been matched) was used to handle confounding factors, with the balance of covariate distribution between HSCT and non-HSCT groups assessed using standardised mean differences. The primary endpoint was progression-free survival in the matched intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02520908), and is currently active but not recruiting.

FINDINGS

From June 1, 2016, to March 3, 2022, total of 99 participants were enrolled at 17 centres in France. Participants with a sibling or matched unrelated donor were assigned to allogeneic HSCT (HSCT group, n=55 [56%]) and participants without a donor were assigned to non-allogeneic HSCT treatment (non-HSCT group, n=44 [44%]). The median follow-up among survivors was 12·6 months (IQR 11·0-35·2). In the HSCT group, 51 participants (93%) were 1:1 matched to participants from the non-HSCT group. In the intention-to-treat analysis, median progression-free survival was significantly longer in the HSCT group (9·0 months [95% CI 6·6-30·5]) than in the non-HSCT group (3·0 months [2·0-6·3]), with a hazard ratio of 0·38 (95% CI 0·21-0·69; p<0·0001). In the per-protocol population, 40 participants (78%) in the HSCT group had 101 serious events and 29 participants (67%) in the non-HSCT group had 70 serious adverse events. The most common serious adverse event other than graft-versus-host disease in both groups was infections, occurring in 30 participants (59%) in the HSCT group and in 19 participants (44%) in the non-HSCT group.

INTERPRETATION

Allogeneic HSCT was associated with significantly longer progression-free survival in participants with advanced-stage CTCLs. These results indicate that allogeneic HSCT treatment should be made available to individuals with high-risk, advanced-stage mycosis fungoides or Sézary syndrome who achieve pre-transplant disease remission.

FUNDING

French Ministry of Health, National Cancer Institute, Programme Hospitalier de Recherche Clinique en Cancérologie.

Are we there yet? cellular therapies for cutaneous T cell lymphoma

Cutaneous T cell lymphomas (CTCLs) are a heterogenous group of skin-involved T-cell non-Hodgkin lymphoma which Mycosis Fungoides and Sezary Syndrome are the most common variants. Despite considerable progress in distinguishing the pathophysiology, the treatment options are still limited for advanced-stage disease. Recent approval of novel agents such as vorinostat, brentuximab vedotin and mogamulizumab paved a way. Allogeneic hematopoietic stem cell transplantation has been shown to be a feasible option in selected advanced-stage CTCL patients. Chimeric antigen receptor (CAR) T cells have been promising for the treatment of B-cell tumors and have been approved for second-line treatment in non-Hodgkin's lymphoma. Although several obstacles still need to be addressed, CAR T cell treatment for CTCLs seems not far off. This review discusses new discoveries in pathophysiology, the state of cellular therapies in current practice, challenges for cellular treatment in advanced CTCL, and how to overcome these challenges.

Neue Therapien kutaner T-Zell-Lymphome

Kutane Lymphome gehören zu den seltenen Erkrankungen. Sie stellen eine heterogene Gruppe mit sehr unterschiedlicher klinischer Symptomatik und Prognose dar. Aufgrund der Komplexität der Erkrankung ist die Einbeziehung eines spezialisierten Zentrums empfehlenswert.

Wir stellen im Folgenden drei Patienten mit primär kutanen T-Zell-Lymphomen (CTCL) aus unserem Hauttumorzentrum vor. Anhand dieser Fallbeispiele möchten wir die multimodale Therapie von CTCL unter Berücksichtigung neu zugelassener Medikamente für diese Indikation beschreiben.

Radiotherapie kutaner Lymphome

Hintergrund

Primär kutane Lymphome (KL) sind sehr strahlenempfindlich. Deshalb ist die Strahlentherapie ein integraler Bestandteil der multimodalen Behandlung.

Ziel der Arbeit

Die vorliegende Arbeit ermöglicht einen Überblick über Indikationen, Entwicklungen der Techniken und Dosiskonzepte der Ganzhautelektronenbestrahlung (TSEBT), der lokalen Radiatio sowie Erhaltungstherapien und aktuelle Kombinationsstudien kutaner T‑ und B‑Zell-Lymphome.

Material und Methoden

Es erfolgte eine selektive Literaturrecherche über die Datenbank PubMed zur Radiotherapie der KL, eine Recherche aktueller Studien mittels clinicaltrials.gov, Darstellung interner Behandlungsstrategien sowie Zusammenfassung der nationalen und internationalen Leitlinien.

Ergebnisse

Die Niedrigdosis-TSEBT wird als Alternative zur konventionellen 36-Gy-TSEBT national und international empfohlen. Die wichtigsten Vorteile sind die bessere Verträglichkeit, die Möglichkeit der Wiederholung, ein verkürzter Verlauf (ca. 3 Wochen) und eine kurze Dauer bis zum Ansprechen. In den aktuellen Studien wird die TSEBT in der Regel mit 12 Gy durchgeführt und mit unterschiedlichen Immuntherapeutika und epigenetischen Regulatoren kombiniert. Die lokale Radiatio ist indiziert bei Tumoren der Mycosis fungoides und ein kuratives Behandlungsschema für andere KL, insbesondere bei primär kutanen B‑Zell-Lymphomen.

Diskussion

Die TSEBT ist eine sehr effektive Behandlungsoption der Mycosis fungoides (MF) und bietet einen wichtigen palliativen Nutzen, da sie zügig zur Symptomlinderung und Verbesserung der Lebensqualität führt. Sie ist eine wichtige Behandlungsoption, insbesondere bei Patienten mit ausgeprägten generalisierten Plaques oder im Tumorstadium. Die lokale Radiatio wird im Rahmen der TSEBT für Tumoren und Aufsättigung unterversorgter Areale eingesetzt. Andere KL sind primär kurativ mit einer lokalen Radiatio behandelbar.

New developments in skin-directed treatments of cutaneous T-cell lymphoma

The therapeutic approach for mycosis fungoides, the most common type of primary cutaneous T-cell lymphoma, is based mainly on the stage of the disease, and skin-directed treatment is recommended by all international guidelines as the first-line treatment in early-stage disease. Skin-directed treatments may be also given in combination with systemic therapies in early-stage mycosis fungoides patients recalcitrant to different types of skin-directed treatments, or in certain patients with high-risk features. Advanced-stage mycosis fungoides is treated mainly with systemic treatments, which may be combined with skin-directed treatments. Due to the rarity of mycosis fungoides, controlled clinical trials of the different skin-directed treatment modalities are almost non-existent, with a few exceptions, and therefore recommendations are largely based on cohort studies and expert opinion. This paper reviews the new developments in skin-directed treatments and provides an update on new studies of already well-known therapies, and an update on novel treatments.

Genetic and epigenetic insights into cutaneous T-cell lymphoma

Primary cutaneous T-cell lymphomas (CTCL) constitute a heterogeneous group of non-Hodgkin T-cell lymphomas that present in the skin. In recent years significant progress has been made in the understanding of the pathogenesis of CTCL. Progress in CTCL classifications combined with technical advances, in particular next generation sequencing (NGS), enabled a more detailed analysis of the genetic and epigenetic landscape and transcriptional changes in clearly defined diagnostic entities. These studies not only demonstrated extensive heterogeneity between different CTCL subtypes but also identified recurrent alterations that are highly characteristic for diagnostic subgroups of CTCL. The identified alterations in particular involve epigenetic remodelling, cell cycle regulation, and the constitutive activation of targetable, oncogenic pathways. In this respect, aberrant JAK-STAT signaling is a recurrent theme, however not universal for all CTCL and with seemingly different underlaying causes in different entities. A number of the mutated genes identified are potentially actionable targets for the development of novel therapeutic strategies. Moreover, these studies have produced an enormous amount of information that will be critically important for the further development of improved diagnostic and prognostic biomarkers that can assist in the clinical management of CTCL patients. In the present review the main findings of these studies in relation to their functional impact on the malignant transformation process are discussed for different subtypes of CTCL.

How to Sequence Therapies in Mycosis Fungoides

OPINION STATEMENT

Choice of therapy in mycosis fungoides is based on both patient- and lymphoma-specific factors, such as disease characteristics, comorbidities, symptoms and effect on quality of life, potential associated toxicities of therapy, response and tolerance to prior lines of therapy, and convenience and practicality. Generally, we sequence therapies from least toxic, targeted, nonimmunosuppressive to more toxic, immunosuppressive and from single agent to multiple agents, as necessary. If more toxic, immunosuppressive agents are required to alleviate disease burden or symptoms, we generally use them just long enough to control the disease, then transition to a maintenance regimen with less toxic, less immunosuppressive agents.

Formation of Tissue-Resident CD8+ T-Cell Memory

Resident memory CD8⁺ T (Trm) cells permanently reside in nonlymphoid tissues where they act as a first line of defense against recurrent pathogens. How and when antigen-inexperienced CD8⁺ T cells differentiate into Trm has been a topic of major interest, as knowledge on how to steer this process may be exploited in the development of vaccines and anticancer therapies. Here, we first review the current understanding of the early signals that CD8⁺ T cells receive before they have entered the tissue and that govern their capacity to develop into tissue-resident memory T cells. Subsequently, we discuss the tissue-derived factors that promote Trm maturation in situ. Combined, these data sketch a model in which a subset of responding T cells develops a heightened capacity to respond to local cues present in the tissue microenvironment, which thereby imprints their ability to contribute to the tissue-resident memory CD8⁺ T-cell pool that provide local control against pathogens.

Allogeneic Hematopoietic Stem Cell Transplantation in Cutaneous T-Cell Lymphomas

Simple Summary

Advanced-stage cutaneous T-cell lymphomas are aggressive diseases with frequent disease relapses and a reduced overall survival. Most treatment regimens fail to induce long-term remissions. Allogeneic hematopoietic stem cell transplantation has been associated with treatment-free long-term remissions and holds a potential for cure in this disease but is associated with frequent complications, mostly linked to the development of graft-versus-host disease and infections. Herein, we review the current evidence supporting the use of allogeneic stem cell transplantation in advanced-stage cutaneous T-cell lymphomas.

Abstract

Cutaneous T-cell lymphomas (CTCLs) are non-Hodgkin lymphomas that develop primarily in the skin. They account for almost 80% of primary cutaneous lymphomas. Epidermotropic CTCLs (mycosis fungoides (MF) and Sézary syndrome (SS)) are the most common form of CTCL. The course of the disease ranges from an indolent clinical behavior in early-stage disease to an aggressive evolution in the advanced stages. Advanced-stage disease is defined by the presence of tumors, erythroderma, or significant blood, nodal or visceral involvement. Advanced-stage disease is characterized by frequent disease relapses, refractory disease, a severely impaired quality of life and reduced overall survival. In the last twenty-five years, allogeneic hematopoietic stem cell transplantation (HSCT) has led to prolonged remissions in advanced CTCL, presumably linked to a graft-versus-lymphoma effect and is thus emerging as a potential cure of the disease. However, the high post-transplant relapse rate and severe morbidity and mortality associated with graft-versus-host disease and infections are important issues. Allogeneic HSCT is thus mostly considered in young patients with no comorbidities and an aggressive, advanced-stage CTCL. Allogeneic HSCT gives the best results in patients with a pre-transplant complete remission of the lymphoma. For this reason, one of the challenges is to define the best time to consider allogeneic HSCT in the disease course. Early identification of patients at high risk for progression is important to identify candidates who may benefit from allogeneic HSCT before their disease becomes treatment-refractory. This review describes the role of allogeneic HSCT in CTCL, summarizes the published data and future perspectives in this area.