Monotherapy and combination therapy with acitretin for mycosis fungoides: results of a retrospective, multicentre study

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.

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.

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.

Suggested Guidelines for the Treatment of Mycosis Fungoides in Countries with Limited Resources

The treatment options for mycosis fungoides (MF) have been expanding but unfortunately many of the currently used treatment modalities are unavailable in Egypt and other African/Arab countries. In addition, there is a lack of consensus on the treatment of hypopigmented MF (HMF), which is a frequently encountered variant in our population. We aimed to develop regional treatment guidelines based on the international guidelines but modified to encompass the restricted treatment availability and our institutional experience. Special attention was also given to studies conducted on patients with skin phototype (III-IV). Treatment algorithm was formulated at Ain-Shams cutaneous lymphoma clinic through the collaboration of dermatologists, haematologists, and oncologists. Level of evidence is specified for each treatment option. For HMF, phototherapy is recommended as a first line treatment, while low-dose methotrexate is considered a second line. For early classical MF, we recommend Psoralen-ultraviolet A (PUVA), which is a well-tolerated treatment option in dark phenotype. Addition of either retinoic acid receptor (RAR) agonist and/or methotrexate is recommended as a second line. Total skin electron beam (TSEB) is considered a third-line option. For advanced stage, PUVA plus RAR agonist and/or methotrexate is recommended as first line, TSEB or monochemotherapy is considered a second line option. Polychemotherapy is regarded as a final option. All patients with complete response (CR) enter a maintenance and follow-up schedule. We suggest a practical algorithm for the treatment of MF for patients with dark phenotype living in countries with limited resources.

Phototherapy combined with systemic agents for mycosis fungoides

The choice of tactics for managing a patient with mycosis fungoides is determined by the stage of the disease. In the early stages of mycosis fungoides, a treatment approach using external therapy and various ultraviolet irradiation spectra (UVB-311 nm and PUVA therapy) is preferable. With insufficient efficiency and / or short remissions in some patients, it is possible to use combined methods in the early stages: PUVA therapy or UVB-311 nm therapy. in combination with systemic therapy, including interferon (IFN) 2b preparations, methotrexate and retinoids. The results of original studies demonstrate an increase in the overall response rate when combining PUVA therapy with IFN- or retinoids in patients with stages IB-IIB. The effectiveness of combined treatment regimens using UVB-311 nm remains insufficiently studied.

Low-dose total skin electron beam therapy plus oral bexarotene maintenance therapy for cutaneous T-cell lymphoma

BACKGROUND

Total skin electron beam therapy (TSEBT) combined with systemic therapy or maintenance treatment is a reasonable approach to enhance the remission rate and duration in mycosis fungoides (MF) and Sézary syndrome (SS). This study assesses the efficacy of oral bexarotene therapy after low-dose TSEBT for patients with MF and SS.

METHODS

In this prospective observational study, we recruited MF/SS patients for treatment with low-dose total skin electron beam therapy (TSEBT) with or without bexarotene therapy to describe outcomes and toxicities.

RESULTS

Forty-six subjects with MF or SS underwent TSEBT between 2016 and 2021 at our institute. Following TSEBT, 27 patients (59 %) received oral bexarotene treatment. The median follow-up was 13 months. The overall response rate (ORR) for the cohort was 85 %. The response rate was significantly higher with combined modality (CM) than TSEBT alone (96 % vs. 68 %, p = 0.03). Median progression-free survival (PFS) for the CM was 17 months versus five months following TSEBT alone (p = 0.001). One patient (4 %) in the retinoid group discontinued the bexarotene therapy because of adverse events. The administration of bexarotene therapy did not increase radiation-related toxicities.

CONCLUSIONS

Response rate and progression-free survival might be improved with TSEBT in combination with oral bexarotene compared to TSEBT alone.

Mycosis fungoides and Sézary syndrome: focus on the current treatment scenario

Cutaneous T-cell lymphomas are a heterogeneous group of lymphoproliferative disorders, characterized by infiltration of the skin by mature malignant T cells. Mycosis fungoides is the most common form of cutaneous T-cell lymphoma, accounting for more than 60% of cases. Mycosis fungoides in the early-stage is generally an indolent disease, progressing slowly from some patches or plaques to more widespread skin involvement. However, 20% to 25% of patients progress to advanced stages, with the development of skin tumors, extracutaneous spread and poor prognosis. Treatment modalities can be divided into two groups: skin-directed therapies and systemic therapies. Therapies targeting the skin include topical agents, phototherapy and radiotherapy. Systemic therapies include biological response modifiers, immunotherapies and chemotherapeutic agents. For early-stage mycosis fungoides, skin-directed therapies are preferred, to control the disease, improve symptoms and quality of life. When refractory or in advanced-stage disease, systemic treatment is necessary. In this article, the authors present a compilation of current treatment options for mycosis fungoides and Sézary syndrome.

Novel therapeutic approaches for cutaneous T cell lymphomas

Introduction: Cutaneous T-cell lymphoma (CTCL) is a rare non-Hodgkin's lymphoma, characterized by malignant T cells infiltrating the skin. CTCL exhibits vast heterogeneity which complicates diagnosis and therapeutic strategies. Current CTCL treatment includes skin-directed therapies (such as topical corticosteroid, topical mechlorethamine, topical bexarotene, ultraviolet phototherapy and localized radiotherapy), total skin electron beam therapy and systemic therapies. Elucidation of molecular and signaling pathways underlying CTCL pathogenesis leads to identification of innovative and personalized treatment schemes.Areas covered: The authors reviewed the molecular and immunological aspects of CTCL with special focus on Mycosis Fungoides (MF), Sézary Syndrome (SS) and associated systemic treatment. A literature search was conducted in PubMed and Web of Science for peer-reviewed articles published until November 2020. Novel treatment approaches including retinoids, targeted therapies, immune checkpoint and JAK/STAT inhibitors, histones deacetylase (HDAC) and mTOR inhibitors as well as proteasome inhibitors, are discussed as potential therapeutic tools for the treatment of CTCL.Expert opinion: Novel therapeutic agents exhibit potential beneficial effects in CTCL patients of high need for therapy such as refractory early stage cutaneous and advanced stage disease. Therapeutic schemes employing a combination of novel agents with current treatment options may prove valuable for the future management of CTCL patients.