Update on erythrodermic cutaneous T-cell lymphoma: report of the International Society for Cutaneous Lymphomas

Evaluation of Sézary cell marker expression and cell death behaviour upon in vitro treatment by flow cytometry in Sézary syndrome patients

The diagnosis of Sézary syndrome (SS) relies on the identification of blood Sézary cells (SC) by different markers via flow cytometry. Treatment of SS is challenging since its pathogenesis is characterized by cell death resistance rather than hyperproliferation. In this study, we establish an integrated approach that considers both the expression of SC markers and sensitivity to cell death both spontaneously and upon in vitro treatment. Peripheral blood mononuclear cells were isolated from 20 SS patients and analysed for the SC markers CD7 and CD26 loss as well as CD158k and PD1 gain. The cells were then treated with different established and experimental therapies in vitro and cell death was measured. Spontaneous and therapeutically induced cell death were measured and correlated to cellular marker profiles. In the marker-positive cells, spontaneous cell death sensitivity was reduced. Different treatments in vitro managed to specifically induce cell death in the putative CTCL cell populations. Interestingly, a repeated analysis after 3 months of treatment revealed the CTCL cell death sensitivity to be restored by therapy. We propose this novel integrated approach comprising the evaluation of SC marker expression and analysis of cell death sensitivity upon treatment that can also enable a better therapy stratification.

Sézary Syndrome in West Sweden: Exploring Epidemiology, Clinical Features, and Treatment Patterns in a Registry-Based Retrospective Analysis

Sézary syndrome (SS) is a rare primary cutaneous T-cell lymphoma variant. Despite various treatment options, it remains incurable, with a poor prognosis. There is an urgent need for additional descriptive research to enhance our understanding and treatment of SS. The aim of this retrospective register-based study was to outline patients' demographic characteristics; investigate the clinical, histopathological, and molecular findings; and assess treatment effectiveness with a focus on time to next treatment (TTNT) and disease progression. Data on 17 patients with SS were obtained from the primary cutaneous lymphoma register in West Sweden between 2012 and 2024. The results revealed that not all patients exhibited the classical triad of symptoms at diagnosis, emphasizing the need for personalized diagnostic approaches. The median survival was only 2.1 years, which reflects the aggressive nature of SS. The longest median TTNT was observed in triple therapy involving retinoids, interferon alpha, and extracorporeal photopheresis (ECP). There was no significant difference in TTNT between various lines of treatment. Early initiation of ECP treatment did not result in improved outcomes. This study highlights the importance of combination therapy for improved outcomes and underscores the need for future studies to identify optimal treatment approaches.

As serious as Sézary

Sézary syndrome is a rare condition, with a very poor prognosis. This case highlights how important it is for clinicians to be cognizant of the impact that this condition and the various treatment regimens can have on patients’ lives.

Sezary Syndrome: A Case Report and Review of Current Therapeutics

Sezary syndrome (SS) is a rare but aggressive type of cutaneous T-cell lymphoma (CTCL). Patients with SS have characteristic skin lesions (erythroderma) and a leukemic phase. The rash associated with CTCLs can often mimic common benign skin conditions such as psoriasis, atopic dermatitis, etc. and therefore can go undiagnosed until later stages. We present a case of a patient with SS who managed eczema for over one year with topical steroids before receiving a skin biopsy. Workup confirmed leukemic involvement, and the patient was started on systemic therapy with bexarotene. The patient continues to have a good response to systemic therapy. When treating patients with persistent rash of uncertain etiology and/or unresponsive to treatment, primary care physicians and internists need to consider SS/Mycosis fungoides as a possible differential and should have a low threshold to initiate early referral to dermatology for definitive diagnosis.

Retinoid X Receptor agonists as selective modulators of the immune system for the treatment of cancer

Upon heterodimerizing with other nuclear receptors, retinoid X receptors (RXR) act as ligand-dependent transcription factors, regulating transcription of critical signaling pathways that impact numerous hallmarks of cancer. By controlling both inflammation and immune responses, ligands that activate RXR can modulate the tumor microenvironment. Several small molecule agonists of these essential receptors have been synthesized. Historically, RXR agonists were tested for inhibition of growth in cancer cells, but more recent drug discovery programs screen new molecules for inhibition of inflammation or activation of immune cells. Bexarotene is the first successful example of an effective therapeutic that molecularly targets RXR; this drug was approved to treat cutaneous T cell lymphoma and is still used as a standard of care treatment for this disease. No additional RXR agonists have yet achieved FDA approval, but several promising novel compounds are being developed. In this review, we provide an overview of the multiple mechanisms by which RXR signaling regulates inflammation and tumor immunity. We also discuss the potential of RXR-dependent immune cell modulation for the treatment or prevention of cancer and concomitant challenges and opportunities.

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

HLA-DR Helps to Differentiate Erythrodermic Cutaneous T-cell Lymphoma from Erythrodermic Inflammatory Dermatoses in Flow Cytometry

Differential diagnosis of erythroderma is challenging in dermatology, especially in differentiating erythrodermic cutaneous T-cell lymphoma from erythrodermic inflammatory dermatoses. This study retrospectively reviewed the peripheral blood flow cytometric results of 73 patients diagnosed with erythroderma at Peking University First Hospital from 2014 to 2019. The flow cytometry antibody panel included white blood cell markers, T-cell markers, B-cell markers, T-cell activation markers, and T helper cell differentiation markers. Features of the cell surface antigens were compared between 34 patients with erythrodermic cutaneous T-cell lymphoma and 39 patients with erythrodermic inflammatory dermatoses. The percentage of HLA-DR+/CD4+T cells was the most pronounced marker to distinguish erythrodermic cutaneous T-cell lymphoma from erythrodermic inflammatory dermatoses, with a threshold of 20.85% (sensitivity 96.77%, specificity 70.37%, p = 0.000, area under the curve (AUC) 0.882), suggesting its potential capability in the differential diagnosis of erythrodermic cutaneous T-cell lymphoma from erythrodermic inflammatory dermatoses. Moreover, in contrast to erythrodermic inflammatory dermatoses, the percentage of Th17 cells was significantly downregulated in erythrodermic cutaneous T-cell lymphoma (p = 0.001), demonstrating a dysregulated immune environment in erythrodermic cutaneous T-cell lymphoma.

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

Mycosis fungoides and Sézary syndrome

Mycosis fungoides (MF) and Sézary syndrome (SS) are a distinct disease entity of cutaneous T-cell lymphoma with heterogenous clinical features and prognosis. MF mainly involves skin and usually shows an indolent and favorable clinical course. In patients with advanced-stage disease, extracutaneous involvement including lymph nodes, viscera, and blood, or large cell transformation may be observed. SS is a leukemic form of advanced-stage MF, characterized by generalized erythroderma. Early-stage MF can be treated with skin-directed therapy. However, patients with refractory or advanced-stage disease are associated with severe symptoms or poor prognosis, requiring systemic therapy. Recent progress in understanding the pathogenesis of MF/SS has contributed to advances in the management of these rare diseases. This review aims to describe the clinical manifestations, diagnosis, risk stratification, and treatment strategy of MF/SS, focusing on the recent updates in the management of these diseases.

Altered physical phenotypes of leukemia cells that survive chemotherapy treatment

The recurrence of cancer following chemotherapy treatment is a major cause of death across solid and hematologic cancers. In B-cell acute lymphoblastic leukemia (B-ALL), relapse after initial chemotherapy treatment leads to poor patient outcomes. Here we test the hypothesis that chemotherapy-treated versus control B-ALL cells can be characterized based on cellular physical phenotypes. To quantify physical phenotypes of chemotherapy-treated leukemia cells, we use cells derived from B-ALL patients that are treated for 7 days with a standard multidrug chemotherapy regimen of vincristine, dexamethasone, and L-asparaginase (VDL). We conduct physical phenotyping of VDL-treated versus control cells by tracking the sequential deformations of single cells as they flow through a series of micron-scale constrictions in a microfluidic device; we call this method Quantitative Cyclical Deformability Cytometry. Using automated image analysis, we extract time-dependent features of deforming cells including cell size and transit time (TT) with single-cell resolution. Our findings show that VDL-treated B-ALL cells have faster TTs and transit velocity than control cells, indicating that VDL-treated cells are more deformable. We then test how effectively physical phenotypes can predict the presence of VDL-treated cells in mixed populations of VDL-treated and control cells using machine learning approaches. We find that TT measurements across a series of sequential constrictions can enhance the classification accuracy of VDL-treated cells in mixed populations using a variety of classifiers. Our findings suggest the predictive power of cell physical phenotyping as a complementary prognostic tool to detect the presence of cells that survive chemotherapy treatment. Ultimately such complementary physical phenotyping approaches could guide treatment strategies and therapeutic interventions. Insight box Cancer cells that survive chemotherapy treatment are major contributors to patient relapse, but the ability to predict recurrence remains a challenge. Here we investigate the physical properties of leukemia cells that survive treatment with chemotherapy drugs by deforming individual cells through a series of micron-scale constrictions in a microfluidic channel. Our findings reveal that leukemia cells that survive chemotherapy treatment are more deformable than control cells. We further show that machine learning algorithms applied to physical phenotyping data can predict the presence of cells that survive chemotherapy treatment in a mixed population. Such an integrated approach using physical phenotyping and machine learning could be valuable to guide patient treatments.

Cutaneous T-cell lymphomas: 2023 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or the blood involvement are generally approached with systemic therapies, including biologic-response modifiers, histone deacetylase inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

Molecular pathogenesis of Cutaneous T cell Lymphoma: Role of chemokines, cytokines, and dysregulated signaling pathways

Cutaneous T cell lymphomas (CTCLs) are a heterogeneous group of lymphoproliferative neoplasms that exhibit a wide spectrum of immune-phenotypical, clinical, and histopathological features. The biology of CTCL is complex and remains elusive. In recent years, the application of next-generation sequencing (NGS) has evolved our understanding of the pathogenetic mechanisms, including genetic aberrations and epigenetic abnormalities that shape the mutational landscape of CTCL and represent one of the important pro-tumorigenic principles in CTCL initiation and progression. Still, identification of the major pathophysiological pathways including genetic and epigenetic components that mediate malignant clonal T cell expansion has not been achieved. This is of prime importance given the role of malignant T cell clones in fostering T helper 2 (Th2)-bias tumor microenvironment and fueling progressive immune dysregulation and tumor cell growth in CTCL patients, manifested by the secretion of Th2-associated cytokines and chemokines. Alterations in malignant cytokine and chemokine expression patterns orchestrate the inflammatory milieu and influence the migration dynamics of malignant clonal T cells. Here, we highlight recent insights about the molecular mechanisms of CTCL pathogenesis, emphasizing the role of cytokines, chemokines, and associated downstream signaling networks in driving immune defects, malignant transformation, and disease progression. In-depth characterization of the CTCL immunophenotype and tumoral microenvironment offers a facile opportunity to expand the therapeutic armamentarium of CTCL, an intractable malignant skin disease with poor prognosis and in dire need of curative treatment approaches.

PD-1 improves accurate detection of Sezary cells by flow cytometry in peripheral blood in mycosis fungoides/Sezary syndrome

BACKGROUND

Accurate Sezary cell detection in peripheral blood of mycosis fungoides/Sezary syndrome (MF/SS) patients by flow cytometry can be difficult due to overlapping immunophenotypes with normal T cells using standard markers. We assessed the utility of programmed death-1 (PD-1/CD279), a transmembrane protein expressed in some hematopoietic cells, for identification and quantitation of circulating Sezary cells among established markers using flow cytometry.

METHODS

50 MF/SS and 20 control blood samples were immunophenotyped by flow cytometry. Principal component analysis (PCA) assessed contributions of antigens to separation of abnormal from normal T cell populations. PD-1 was assessed over time in blood and bone marrow of available MF/SS cases.

RESULTS

Normal CD4+ T cells showed dim/intermediate to absent PD-1 expression. PD-1 in Sezary cells was informatively brighter (≥1/3 log) than internal normal CD4+ T cells in 39/50 (78%) cases. By PCA, PD-1 ranked 3rd behind CD7 and CD26 in population separation as a whole; it ranked in the top 3 markers in 32/50 (64%) cases and 1st in 4/50 (8%) cases when individual abnormal populations were compared to total normal CD4+ T cells. PD-1 clearly separated Sezary from normal CD4+ T cells in 15/26 (58%, 30% of total) cases with few and subtle alterations of pan-T cell antigens/CD26 and was critical in 6 (12% of total), without which identification and quantification were significantly affected or nearly impossible. PD-1 remained informative in blood/bone marrow over time in most patients.

CONCLUSIONS

PD-1 significantly contributes to accurate flow cytometric Sezary cell assessment in a routine Sezary panel.

Mature T-Cell leukemias: Challenges in Diagnosis

T-cell clones can frequently be identified in peripheral blood. It can be difficult to appreciate whether these are benign and transient or whether they signify a clonal disorder. We review factors that aid in understanding the relevance of T-cell clones. Conversely, obvious pathological T-cell clones can be detected in blood, but there is uncertainty in how to categorize this clonal T cell population, thus, we adopt a multidisciplinary review of the clinical features, diagnostic material and radiology before making the diagnosis. In this review we shall discuss some of these challenges faced when diagnosing mature T-cell leukemias.

Cutaneous T-cell lymphomas: 2021 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multi-disciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with systemic therapies, including biologic-response modifiers, histone deacetylase inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

Extracorporeal photopheresis and multimodality therapy in patients with T-cell cutaneous lymphomas: Real-life experience in Argentina

BACKGROUND

Extracorporeal photopheresis (ECP) as a part of multimodality therapy, is one of the treatments for Sézary syndrome (SS) and advanced stage mycosis fungoides (MF). This study aims to describe cutaneous and peripheral blood responses of patients with MF and SS who received multimodality therapy.

METHODS

In this cross-sectional retrospective study, patients with MF or SS who received ECP treatment in combination with at least one additional systemic treatment between 2011 and 2018 were included. ECP consisted of a two-session cycle every 2 to 4 weeks. Cutaneous and blood responses were evaluated with updated criteria.

RESULTS

Twenty-eight patients (11 (39%) with MF and 17 (51%) with SS) were included. Their median age at diagnosis was 63 (57-67) years. The median number of treatments before ECP was 2 (1-3). Seven out of 11 patients with MF (63%) underwent an assessment of cutaneous response. Five patients (70%) presented a partial response; 1 (15%), stable disease, and 1 (15%) progressive disease. Thirteen of the 17 patients with SS (76%) underwent evaluation. One patient (8%) presented a complete cutaneous response; 6 (46%), a partial response; 5 (38%), stable disease; and 1 (8%), progressive disease. None of them relapsed during the study period in both groups. No ECP-related adverse effects occurred during the study.

CONCLUSION

Most patients with SS and MF who underwent multimodality therapy with ECP had favorable cutaneous and blood response. It is safe to combine ECP with other treatments. Studies with large numbers of patients are necessary to assess the effects of ECP on patient survival.

Reactive Langerhans Cell Proliferation Mimicking Langerhans Cell Histiocytosis in Association with Sézary Syndrome: A Case Report and Literature Review

Sézary syndrome (SS) is a rare type of cutaneous T-cell lymphoma (CTCL) that is characterized by erythroderma, lymphadenopathy and circulating clonal T-cells (Sézary cells). However, to our knowledge, reactive Langerhans cell (LC) proliferation mimicking Langerhans cell histiocytosis (LCH) associated with SS has not been reported. In this report, we describe an unusual case of reactive LC proliferation mimicking LCH associated with SS in a 57-year-old female patient. With complaints of recurrent skin symptoms and enlarged lymph nodes (LNs), she was admitted to our center with a presumptive diagnosis of LCH as demonstrated by LN biopsy pathology. However, other than adenopathy, no lesions were noted in any organ system commonly involved in LCH. Typical Sézary cells were identified through morphology and further confirmed by flow cytometric immunophenotyping in peripheral blood (PB) and bone marrow (BM). In addition, T-cell receptor gene rearrangement was positive, whereas the BRAF V600E gene mutation was negative in skin, LN, PB and BM. The patient was ultimately diagnosed with SS with reactive LC proliferation. This case should remind clinicians to be wary of diagnosing LCH if LCH-like pathology occurs exclusively in LNs. Moreover, morphologic, immunologic, cytogenetic and molecular biologic studies should be performed to avoid misdiagnosis.

Characteristics and outcomes of 727 patients with mycosis fungoides and Sézary syndrome from a Brazilian cohort

BACKGROUND

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most prevalent cutaneous lymphomas. They were not described in a large Brazilian cohort yet. We aimed, with this single-center, retrospective cohort analysis, to describe the characteristics and outcomes of MF/SS in a tertiary public health service in Brazil.

METHODS

MF/SS patients evaluated at the University of São Paulo Medical School between 1989 and 2018 were included. Data were collected at diagnosis. Demographic, clinical, histopathological, immunopathological, molecular, laboratory, and follow-up data were analyzed.

RESULTS

Among 727 patients, 92.6% (673) were diagnosed with MF, 7.4% (54) with SS. There were 51.2% (372) of males, 48.8% (355) of females. The median age was 51.8 years; it was higher in erythrodermic MF (60.2) and SS (60.9). Among MF, 41.8% (281) had classic MF, 4.9% (33) folliculotropic MF, 1.8% (12) granulomatous slack skin, and 0.3% (2) pagetoid reticulosis. Common subtypes included erythrodermic (14.1%, 95), hypopigmented (10.8%, 73), and poikilodermatous MF (10.8%, 73). Extracutaneous involvement was rare. Five, 10, 20, and 30-year overall survival rates were 97.3%, 92.4%, 82.6%, and 82.6% for early-stage, and 58.6%, 42.7%, 20.8%, and 15.4% for advanced-stage disease, respectively. After multivariate analysis, SS diagnosis, folliculotropic MF, erythrodermic MF, clinical stage, age (≥60 years), increased lactate dehydrogenase, and large cell transformation conferred poorer prognosis.

CONCLUSIONS

We observed a higher percentage of hypopigmented MF compared to the literature, and demographic (older age) and prognostic (poorer prognosis) similarities between erythrodermic MF and SS, suggesting a possible relationship between these erythrodermic lymphomas. Factors associated with a poorer prognosis were compatible with the literature.

Improved Sézary cell detection and novel insights into immunophenotypic and molecular heterogeneity in Sézary syndrome

Sézary syndrome (SS) is an aggressive leukemic form of Cutaneous T-cell Lymphoma with neoplastic CD4+ T cells present in skin, lymph nodes, and blood. Despite advances in therapy, prognosis remains poor with a 5-year overall survival of 30%. The immunophenotype of Sézary cells is diverse, which hampers efficient diagnosis, sensitive disease monitoring, and accurate assessment of treatment response. Comprehensive immunophenotypic profiling of Sézary cells with an in-depth analysis of maturation and functional subsets has not been performed thus far. We immunophenotypically profiled 24 SS patients employing standardized and sensitive EuroFlow-based multiparameter flow cytometry (MFC). We accurately identified and quantified Sézary cells in blood and performed an in-depth assessment of their phenotypic characteristics in comparison with their normal counterparts in the blood CD4+ T-cell compartment. We observed inter-and intra-patient heterogeneity and phenotypic changes over time. Sézary cells exhibited phenotypes corresponding with classical and non-classical T helper subsets with different maturation phenotypes. We combined MFC analyses with FACS cell sorting and performed RNA-sequencing studies on purified subsets of malignant Sézary cells and normal CD4+ T cells of the same patients. We confirmed pure mono-clonality in Sézary subsets, we compared transcriptomes of phenotypically distinct Sézary subsets and identified novel down-regulated genes, most remarkable THEMIS and LAIR1 which discriminate Sézary cells from normal residual CD4+ T cells. Together, these findings further unravel the heterogeneity of Sézary cell subpopulations within and between patients. These new data will support improved blood staging and more accurate disease monitoring.

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.

Mycosis Fungoides and Sézary Syndrome: An Integrative Review of the Pathophysiology, Molecular Drivers, and Targeted Therapy

Simple Summary

In the last few years, the field of cutaneous T-cell lymphomas has experienced major advances. In the context of an active translational and clinical research field, next-generation sequencing data have boosted our understanding of the main molecular mechanisms that govern the biology of these entities, thus enabling the development of novel tools for diagnosis and specific therapy. Here, we focus on mycosis fungoides and Sézary syndrome; we review essential aspects of their pathophysiology, provide a rational mechanistic interpretation of the genomic data, and discuss the current and upcoming therapies, including the potential crosstalk between genomic alterations and the microenvironment, offering opportunities for targeted therapies.

Abstract

Primary cutaneous T-cell lymphomas (CTCLs) constitute a heterogeneous group of diseases that affect the skin. Mycosis fungoides (MF) and Sézary syndrome (SS) account for the majority of these lesions and have recently been the focus of extensive translational research. This review describes and discusses the main pathobiological manifestations of MF/SS, the molecular and clinical features currently used for diagnosis and staging, and the different therapies already approved or under development. Furthermore, we highlight and discuss the main findings illuminating key molecular mechanisms that can act as drivers for the development and progression of MF/SS. These seem to make up an orchestrated constellation of genomic and environmental alterations generated around deregulated T-cell receptor (TCR)/phospholipase C, gamma 1, (PLCG1) and Janus kinase/ signal transducer and activator of transcription (JAK/STAT) activities that do indeed provide us with novel opportunities for diagnosis and therapy.

Trifarotene: A Current Review and Perspectives in Dermatology

Retinoids have numerous applications in inflammatory, dyskeratotic, and oncohematology diseases. Retinoids have now reached the fourth generation, progressively reducing toxicity whilst increasing their efficacy. Trifarotene is a new fourth-generation retinoid with a selective action on RAR-γ. In this review, we reported the trials—both concluded and in progress—including the use of trifarotene in dermatological diseases. Studies were identified by searching electronic databases (MEDLINE, EMBASE, PubMed, Cochrane, Trials.gov) from 2012 to today and reference lists of respective articles. Only articles published in English language were included. Randomized trials evaluating trifarotene tolerability, safety, and efficacy in congenital ichthyosis and acne have demonstrated great results and mild side effects, leading to the approval by the FDA of trifarotene for the treatment of lamellar ichthyosis in 2014, and of acne vulgaris in October 2019. No high-quality randomized clinical trials have evaluated the treatment of primary cutaneous lymphomas with trifarotene. Finally, we are hypothesizing future perspectives in the treatment of non-melanoma skin cancers, fungal infections, photoaging, and hand-foot skin reactions with trifarotene.

Erythroderma: a prospective study of 309 patients followed for 12 years in a tertiary center

Erythroderma is characterized by erythema and scaling affecting more than 80% of the body surface area. It is potentially life-threatening, and diagnosis of the underlying disease is a challenge. Despite laboratory improvements, many cases remain idiopathic. We aimed to analyze clinical and laboratory findings of 309 erythrodermic patients to find clues to the etiologic diagnosis. We performed a prospective study at the University of São Paulo Medical School, from 2007 to 2018, with patients with acquired erythroderma. Clinical, laboratory, histology, and molecular biology data were collected. The median age at diagnosis was 57 years, with a male-to-female ratio of 2.2. Eczema was the most frequent etiology (20.7%), followed by psoriasis (16.8%), Sézary syndrome (12.3%), drug eruption (12.3%), atopic dermatitis (8.7%), and mycosis fungoides (5.5%). Other diagnoses (6.8%) included pemphigus foliaceous, paraneoplastic erythroderma, adult T-cell leukemia/lymphoma, dermatomyositis, pityriasis rubra pilaris, lichen planus, bullous pemphigoid, and leprosy. In 52 patients (16.8%), it was not possible to elucidate erythroderma etiology. Atopic dermatitis developed erythroderma at an earlier age (median 25 years; P = 0.0001). Acute onset was associated with drug reactions and atopic dermatitis (median time from erythroderma to diagnosis of 1 and 1.5 months, respectively; P = 0.0001). Higher immunoglobulin E levels were observed in atopic dermatitis (median 24,600 U/L; P = 0.0001). Histopathology was helpful and was consistent with the final diagnosis in 72.4%. Monoclonal T-cell proliferation in the skin was observed in mycosis fungoides (33.3%) and Sézary syndrome (90.9%). At the last assessment, 211 patients (69.3%) were alive with disease, 65 (21.7%) were alive without disease, and 27 (9.1%) died with active disease. Erythroderma is a challenging syndrome with a difficult diagnostic approach. Younger age and higher immunoglobulin E levels are associated with atopic dermatitis; acute onset is observed in drug eruptions and atopic dermatitis. Histopathology and molecular biology tests are essential tools in the investigation of erythroderma.

Non-Classic Signs of Sézary Syndrome: A Review

The majority of patients with Sézary syndrome (SS) present with classic symptoms of erythroderma, lymphadenopathy, and pruritus. However, there have been numerous reports of patients with SS who have non-classic signs. In this review, we report the less common clinical presentations of SS and discuss their relevant treatments. Our search included all literature on SS since 2008, the year the World Health Organization (WHO) incorporated the diagnostic criteria for SS into the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. We reviewed 896 articles and identified 505 patients with non-classic presentations of SS. Of these 505 patients, the most common non-classic signs of SS were keratoderma, onychodystrophy, alopecia, leonine facies, and ectropion. Given the aggressive and highly symptomatic nature of SS, it is imperative that clinicians recognize the less common signs of the disease to prevent delays in diagnosis and treatment. To our knowledge, this is the first review of the clinical variations of SS with a focus on non-classic signs and symptoms.

Current status of histone deacetylase inhibitors in cutaneous T-cell lymphoma

Cutaneous T cell lymphoma (CTCL) is a non-Hodgkin's lymphoma with a heterogenous presentation and highly variable disease course. The most common subtypes of CTCL are mycosis fungoides (MF) and Sézary Syndrome (SS). Treatment varies based on the stage of the disease with skin directed therapies typically utilized for early stage disease, and systemic therapies employed for more advanced disease. There are few highly effective treatments available, and systemic therapies have limited response rates. Histone deacetylase inhibitors have emerged as mainstream treatments for MF/SS over the past several years. Here, we discuss the mechanism of action of histone deacetylase inhibitors in relation to the pathogenesis of MF/SS, evaluate the clinical trials that led to Food and Drug Administration approval of two of the histone deacetylase inhibitors for MF/SS and describe the results for those still under investigation. Additionally, we discuss the potential for combination therapies in order to optimize outcomes of treatment with histone deacetylase inhibitors.

High-Scatter Lymphocytes in the Blood of Erythrodermic Cutaneous T-Cell Lymphoma: Evidence for Large-Cell Transformation?

BACKGROUND

Erythrodermic cutaneous T-cell lymphoma consists of erythrodermic mycosis fungoides and Sézary syndrome. Previous studies have indicated that very large Sézary cells (> 14 μm diameter) or the presence of aneuploid cells in the blood might reflect large-cell transformation, with a corresponding poor prognosis.

PATIENTS AND METHODS

A retrospective study assessed data between June 1997 and April 2002 of 32 patients with erythrodermic cutaneous T-cell lymphoma, 4 patients with leukemic mycosis fungoides, and 19 patients with nonneoplastic inflammatory conditions who were referred for evaluation of possible cutaneous T-cell lymphoma. Data were studied by 2-parameter flow cytometry gated on the lymphocyte population.

RESULTS

High-scatter T lymphocytes (HSL) were detected in initial blood samples from 10 of 19 patients with Sézary syndrome, 1 of 13 patients with erythrodermic mycosis fungoides, and no patient with nonneoplastic inflammatory conditions. A significant correlation was found between HSL and very large Sézary cells and histopathologic evidence of large-cell transformation. Moreover, the presence of HSL suggests a poor prognosis even for patients with advanced disease.

CONCLUSION

We propose that HSL are often large transformed neoplastic Sézary cells that may be detected in patients with clinically unapparent large-cell transformation.

Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in erythrodermic cutaneous T-cell lymphoma (CTCL) patients

Erythroderma can occur in cutaneous T-cell lymphoma (CTCL). Staphylococcus aureus (S. aureus) prevalence is increased in CTCL patients and contributes to CTCL disease flares. Our primary aim was to describe S. aureus infections, including resistance patterns and the antibiotic treatment regimens used, in erythrodermic CTCL patients. This was a retrospective chart review of erythrodermic CTCL patients who had S. aureus infection or colonization and were treated at the UT MD Anderson Cancer Center's Melanoma Skin Center between 2012 and 2016. Twenty-six erythrodermic CTCL patients had 50 documented S. aureus colonization or infection events. Patients had an improvement in body surface area (BSA) or modified Severity Weighted Assessment Tool (mSWAT) in 53% events treated for S. aureus. Seventeen of the 50 (34%) events were due to methicillin-resistant S. aureus (MRSA). One-third (33%) of MRSA events were initially treated with dicloxacillin. The MRSA isolates were sensitive to trimethoprim-sulfamethoxazole (92%) and doxycycline (88%). Patients treated in the outpatient setting (OR 0.073; 95% CI 0.008-0.627; p = 0.017) and patients with a previous history of topical anti-S. aureus decolonization treatments before S. aureus event as stand-alone (OR 0.125; 95% CI 0.018-0.887; p = 0.038) or in combination treatment with systemic antibiotics (OR 0.094; 95% CI 0.009-0.944; p = 0.045) were less likely to see improvement in BSA or mSWAT from S. aureus treatment. Treatment of S. aureus improved CTCL skin score in a high number of erythrodermic patients. The MRSA prevalence was high in erythrodermic CTCL patients. Clinicians should consider using empiric MRSA antibiotic coverage for these patients.

Evaluation of Low-Dose, Low-Frequency Oral Psoralen-UV-A Treatment With or Without Maintenance on Early-Stage Mycosis Fungoides: A Randomized Clinical Trial

Importance

Psoralen-UV-A (PUVA) photochemotherapy is standard first-line treatment for skin-limited, early-stage mycosis fungoides capable of producing high initial complete response (CR) rates. However, much remains unknown about PUVA's therapeutic mechanisms, optimal duration and frequency of treatment, dose escalation, or use as maintenance therapy.

Objectives

To evaluate low-dose, low-frequency PUVA, and whether maintenance treatment extends disease-free remission in patients with mycosis fungoides.

Design, Setting, and Participants

This prospective randomized clinical trial with defined PUVA dosing regimen was carried out in 5 centers (Graz, Vienna, Hietzing, Innsbruck, and Salzburg) across Austria. Patients with stage IA to IIA mycosis fungoides (n = 27) were enrolled in the study beginning March 13, 2013, with the last patient enrolled March 21, 2016. These patients were treated with oral 8-methoxypsoralen followed by UV-A exposure 2 times per week for 12 to 24 weeks until CR. Patients with CR were randomized to PUVA maintenance for 9 months (14 total exposures) or no maintenance. The study was conducted from April 27, 2012, to July 27, 2018. Data analysis of the primary end point was of the intention-to-treat population, and the secondary end point analysis was of the evaluable population.

Main Outcomes and Measures

Efficacy of the PUVA regimen was determined by the rate of CR as defined by a modified severity-weighted assessment tool (mSWAT) score reduction to 0. Levels of proinflammatory molecules in serum and histologic features and percentage of clonal T cells in skin were assessed to search for biomarkers of clinical response.

Results

In 27 patients with mycosis fungoides, 19 (70%) were male with mean (range) age 61 (30-80) years. At baseline, patients with CR had a mean (range) mSWAT score of 18.6 (1-66) compared with 16.8 (3-46) in patients with partial response. The 12- to 24-week PUVA induction regimen reduced the mSWAT score in all patients and led to CR in 19 (70%) of 27 patients and a low mean cumulative UV-A dose of 78.5 J/cm2. The subsequent standardized 9-month PUVA maintenance phase prolonged median (range) disease-free remission from 4 (1-20) months to 15 (1-54) months (P = .02). High density of histologic infiltrate and high percentage of clonal TCR sequences in skin biopsy specimens at baseline were inversely associated with therapeutic response. No severe adverse effects were seen during the PUVA induction or maintenance phase.

Conclusions and Relevance

This proof-of-concept study identifies potential biomarkers for therapeutic response to PUVA in mycosis fungoides; it also demonstrates that low-dose, low-frequency PUVA appears to be highly effective, and maintenance treatment may extend disease-free remission.

Trial Registration

ClinicalTrials.gov identifier: NCT01686594.

Cutaneous T-cell lymphoma: Differential diagnostics of erythrodermic conditions

Erythroderma is a condition damaging at least 80–90 % of the skin surface, characterized by erythema and peeling. This condition may be a manifestation of various diseases of the skin and internal organs, including malignant lymphoproliferative disorders. Sézary syndrome and the erythrodermic variant of mycosis fungoides are aggressive forms of cutaneous T-cell skin lymphoma, the diagnostics of which is challenging due to the similar clinical pictures of these diseases with benign dermatoses. This article presents two clinical cases of erythroderma in the setting of cutaneous T-cell lymphoma. An analysis of the anamnestic data, the clinical picture and the results of laboratory examinations in patients suffering from this condition allowed the diagnosis of Sézary syndrome to be confirmed. The presented cases reflect the importance of identifying the causes of erythroderma.

Conflict of interest: the authors state that there is no potential conflict of interest requiring disclosure in this article.

[Atypical Sézary syndrome in a young subject]

INTRODUCTION

Sézary syndrome accounts for 5% of cutaneous T-cell lymphomas, with mean age of onset of 60 years. Erythroderma associated with palmoplantar keratoderma and lymphadenopathy is the usual clinical presentation, but the disease has potentially confusing polymorphic clinical features.

PATIENTS AND METHODS

We report the case of a 27-year-old patient with no notable disease history, presenting generalized non-pruritic dermatosis for 3 months, with erythema and papules, and follicular distribution, localized to the limbs, the trunk and the face. Palmoplantar keratoderma was associated with acral edema. The clinical presentation was initially evocative of pityriasis rubra pilaris. Laboratory tests showed hyperlymphocytosis with Sézary cells in the blood. A diagnosis of grade IVA Sézary syndrome was made based on the skin biopsy results and the PET scan. Screening for KIR3DL2 on T-cells in blood was positive. Extracorporeal photochemotherapy was initiated but cutaneous relapse occurred, leading to combined treatment with bexarotene, which proved ineffictive. Despite numerous chemotherapies (cyclophosphamide, doxorubicin, vincristine, etoposide and prednisone, then dexamethasone, oxaliplatin and cytarabine, associated with brentuximab, vedotin, and, ultimately, clofarabine and endoxan), the patient died after 9 months.

DISCUSSION

Our case illustrates an atypical clinical presentation of cutaneous lymphoma in a young patient. With a fatal outcome in 9 months despite 5 different lines of treatment, our case highlights the aggressive nature of Sézary syndrome as well as the difficulties involved in treating this disease.

CONCLUSION

A diagnosis of Sézary syndrome must be considered in the event of atypical dermatosis in patients of all ages. The presence of lymphomatous clonal cells and Sézary cells in the blood, immunophenotyping of lymphocytes in blood and marrow, and a second reading of the cutaneous biopsy results enabled us to make a diagnosis of Sezary syndrome.

Contemporary Topics in Radiation Medicine: Skin Cancer

Radiation plays an important role in the management of a variety of skin cancers. This article discusses the role of radiation in the treatment of cutaneous squamous cell carcinoma, basal cell carcinoma, Merkel cell carcinoma, cutaneous T-cell lymphoma, and B-cell lymphomas.

Leukaemic variants of cutaneous T-cell lymphoma: Erythrodermic mycosis fungoides and Sézary syndrome

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most common types of cutaneous lymphoma, accounting for approximately 60% of cutaneous T-cell lymphomas. Diagnosis requires correlation of clinical, histologic, and molecular features. A multitude of factors have been linked to the aetiopathogenesis, however, none have been definitively proven. Erythrodermic MF (E-MF) and SS share overlapping clinical features, such as erythroderma, but are differentiated on the degree of malignant blood involvement. While related, they are considered to be two distinct entities originating from different memory T cell subsets. Differential expression of PD-1 and KIR3DL2 may represent a tool for distinguishing MF and SS, as well as a means of monitoring treatment response. Treatment of E-MF/SS is guided by disease burden, patients' ages and comorbidities, and effect on quality of life. Current treatment options include biologic, targeted, immunologic, and investigational therapies that can provide long term response with minimal side effects. Currently, allogeneic stem cell transplantation is the only potential curative treatment.

Mycosis fungoides and Sézary syndrome: 2019 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas (CTCL) are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis fungoides (MF) or Sézary syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multi-disciplinary approach to treatment. For patients with disease limited to the skin, skin-directed therapies are preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with systemic therapies. These include biologic-response modifiers, histone deacetylase (HDAC) inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

A histo-immunopathologic and prognostic study of erythrodermic cutaneous T-cell lymphoma

BACKGROUND

Sézary syndrome (SS) and erythrodermic mycosis fungoides (E-MF) represent two expressions of erythrodermic cutaneous T-cell lymphoma (E-CTCL).

METHODS

Histopathologic features were compared on skin specimens from 41 patients with SS and 70 patients with E-MF. Immunopathologic findings were compared on 42 SS and 79 E-MF specimens.

RESULTS

Specimens of SS usually showed band-like dermal infiltrates with intermediate-sized lymphoid cells and few plasma cells; on the other hand E-MF more often had a perivascular infiltrative pattern, predominance of small/mixed lymphoid cells and eosinophils. SS also had lower numbers of CD8+ cells and higher numbers of CD62L+ cells compared to E-MF. For E-MF patients, the presence of large Pautrier collections, infiltrates with intermediate-sized cells, increased number of mitotic figures and ≥50% CD62L+ cells in the dermal infiltrate correlated with a relatively poor disease-specific survival. However, only the presence of mitotic figures retained prognostic significance with clinical stage as a covariate.

CONCLUSIONS

Clinical stage provides the most important prognostic information for patients with E-CTCL. However, mitotic activity for E-MF and CD8+ cells <20% for SS have additional value. We hypothesize that observed differences in plasma cell and eosinophil numbers may reflect the influence of CD62L+ central memory T-cells in the microenvironment.

Prognostic Significance of Serum Copper in Patients With Cutaneous T-cell Lymphoma

BACKGROUND

Serum copper has been reported to be increased in various cancers, including lymphoma. The purpose of the present study was to investigate the clinical and prognostic importance of serum copper levels in patients with cutaneous T-cell lymphoma (CTCL).

PATIENTS AND METHODS

Serum copper was measured in 60 men and 38 women with mycosis fungoides (MF) and 14 men and 3 women with erythrodermic CTCL (6 with Sézary syndrome) consecutively evaluated from July 1980 to June 1985.

RESULTS

A greater than normal copper level was present in nearly 20% of patients and was associated with an increased risk of disease progression and shortened disease-specific survival for patients with patch or plaque phase MF, but not for those with tumor phase MF or erythrodermic CTCL. In contrast, the serum lactate dehydrogenase level and neutrophil/lymphocyte ratio were not significantly associated with prognosis in our patient cohort.

CONCLUSION

The reason for the association between the high serum copper levels and adverse prognosis is unknown. We hypothesized that interleukin-6 is secreted primarily by non-neoplastic cells at MF skin sites, leading to release of copper by the liver. Local production of interleukin-6 at the lesion sites might conceivably also promote neoplastic cell progression by stimulation of the STAT3 pathway. Further studies on the relationship between activated tumor-associated macrophages, serum copper levels, interleukin-6, or C-reactive protein and prognosis might be informative.

Kutane Lymphome

Kutane Lymphome (cutaneous lymphomas: CL) umfassen die Gruppe der kutanen T-Zell-Lymphome (cutaneous T-cell lymphomas: CTCL), kutanen B-Zell-Lymphome (cutaneous B-cell lymphomas: CBCL) und die sog. hämatodermischen Neoplasien (HN). CL gehören zur Gruppe der Non-Hodgkin-Lymphome (NHL) und stellen in der Subgruppe der extranodalen NHL die zweithäufigste Gruppe hinter den gastrointestinalen Lymphomen dar (Jaffe et al. 2009). Man unterscheidet zwischen primären und sekundären CL. Primäre CL haben ihren Ursprung in der Haut und bleiben in der Regel darauf auch längere Zeit beschränkt, während sekundäre CL kutane Manifestationen von primär nodalen oder extranodalen Lymphomen darstellen (Willemze 2005). Die primären CL unterscheiden sich hinsichtlich klinischem Verlauf, Therapieoptionen und Prognose erheblich von nodalen und extrakutanen Lymphomen. So zeigen z. B. die primär kutanen CD30+-T-Zell-Lymphome einen gutartigen Verlauf, wogegen die nodalen Varianten als aggressiv eingestuft werden. Da die CL zumeist weniger aggressiv sind, werden sie auch weniger aggressiv behandelt.

Merkel cell carcinoma arising in association with cutaneous T-cell lymphoma: A potential diagnostic pitfall

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous neuroendocrine carcinoma with increased prevalence in patients with immunosuppression or B-cell neoplasms. To the best of our knowledge, an association with cutaneous T-cell lymphoma (CTCL) has not been previously described. In this report, we present two cases of MCC arising in the setting of CTCL. The first case was a female during her 70s with previously diagnosed stage IVA1 Sezary syndrome. Biopsy of a scaly patch showed two distinct abnormal cell populations. The first population consisted of hyperchromatic dermal and epidermotropic lymphocytes, expressing CD3 and CD4 with diminished CD7. The second population consisted of intraepidermal clusters of larger atypical cells that expressed synaptophysin, neurofilament, CK20, and Merkel cell polyomavirus transcript. The combination of findings was consistent with intraepidermal MCC in a background of CTCL. Excision showed residual intraepidermal MCC without dermal involvement. The second case was a male during his 50s with a longstanding history of mycosis fungoides, who presented with a new lesion on his right thigh. Biopsy and excision showed dermal MCC without secondary involvement by CTCL. Our cases show that MCC may rarely occur in the setting of T-cell lymphoma, and that intraepidermal MCC may mimic epidermotropic T-cells.

Sézary syndrome without erythroderma: A case report and review of published work

Sézary syndrome (SS) is defined by erythroderma and circulating atypical T cells, with or without lymphadenopathy. Recently, Thompson et al. identified a distinct population of SS patients with an atypical presentation: a high blood tumor burden of Sézary cells fulfilling criteria for SS but without fulfilling the criteria for erythroderma at the diagnosis. Here, we report a case of a 49-year-old Japanese man with SS who did not present with erythroderma initially, but exhibited erythematous itchy papules symmetrically located on the legs and arms. We also reviewed reported cases of SS without initial erythroderma. The skin manifestations at diagnosis varied from patches to tumors often seen in mycosis fungoides, and other rarer findings such as excoriation, palmoplantar keratoderma and alopecia. Pruritus was reported in most patients (86%), unlike early mycosis fungoides, and could be the main clue to the diagnosis of SS. Notably, three patients were reported to have presented with papular lesions, similar to our case. Little is known about why skin lesions in SS without erythroderma vary and why these cases did not exhibit erythroderma initially. Attenuated stimulation by colonized Staphylococcus aureus, impairment in recruitment of malignant T cells and suppression of inflammatory response induced by malignant T cells with regulatory phenotype may be associated with skin manifestations. Further studies are necessary to elucidate the etiology of this entity.

Naïve/memory T-cell phenotypes in leukemic cutaneous T-cell lymphoma: Putative cell of origin overlaps disease classification

BACKGROUND

Mycosis fungoides (MF) and Sézary Syndrome (SS) are clinically distinct cutaneous T-cell lymphomas with strikingly similar morphologic and phenotypic features. Prior studies have suggested phenotypic differences based on markers of antigen experience, suggesting a different cell of origin.

METHODS

Seventy-nine involved peripheral blood or bone marrow samples from 33 patients with SS and 19 patients with MF were studied by 10-color flow cytometry, including CD62L, CD45RA, CCR4, and PD-1. Gated tumor events were classified as naïve (T_N ), central memory (T_CM ), effector memory (T_EM ), or effector memory with reacquired CD45RA (T_EMRA ); based on CD62L⁺ /CD45RA⁺ , CD62L⁺ /CD45RA^- , CD62L^- /CD45RA^- , or CD62L^- /CD45RA⁺ phenotype, respectively. Sequential specimens were compared to assess for phenotypic stability.

RESULTS

The naïve/memory phenotype of the neoplastic T-cells was markedly heterogeneous, with a dominant T_N , T_CM , T_EM , or T_EMRA subset on 11 (14%), 32 (41%), 30 (38%), and 6 (8%) cases, respectively. There was no correlation between the diagnosis of MF or SS and putative cell of origin (P = 0.4). Overexpression of CCR4 and PD1 was observed in most cases, with higher intensity in SS compared to MF. The naïve/memory phenotype remained the same for 10 patients up to 273 days after the initial analysis; while on six patients, the naïve/memory phenotype was different from the original phenotype.

CONCLUSIONS

Both SS and MF can have phenotypic features of any of the major naïve/memory T-cell subsets, which questions the current principle of "cell-of-origin" distinction between SS and MF. Phenotypic shifts within these subsets are common, suggesting a functional state rather than a cell-of-origin surrogate. © 2018 International Clinical Cytometry Society.

Dermoscopy of Lymphomas and Pseudolymphomas

Primary cutaneous lymphomas are a heterogeneous group that includes 2 main groups of primary T- and B-cell lymphomas, which can involve the skin with distinct variability in clinical presentation, histopathology, immunophenotypes, molecular signature, and prognosis. The authors describe the most frequent clinical forms of cutaneous lymphomas and their dermoscopic features. Even if the diagnosis of these entities is still based on a cellular level and the literature on dermoscopy in cutaneous lymphomas is limited and, for several entities it is based only on single case reports/case series, we think that know how they appear also in dermoscopy can be useful for helping in the clinical diagnosis.

Integrating novel systemic therapies for the treatment of mycosis fungoides and Sézary syndrome

Novel systemic therapies are generally prescribed to patients with advanced-stage disease or those with early-stage disease refractory to skin-directed therapies. In general, systemic chemotherapy should be reserved for patients who fail to respond to biological agents. Such biological agents include interferon alfa, bexarotene, histone deacetylase inhibitors (vorinostat, romidepsin), brentuximab vedotin and mogamulizumab. Extracorporeal photopheresis is particularly effective for patients with Sézary Syndrome. Allogeneic transplantation is becoming increasing used for younger patients. Novel agents in advanced development include the monoclonal antibody IPH4102,duvelisib,and the new modified formulation of denileukin diftitox. The choice of agents for patients is typically a balance of patient factors (age, co-morbidities, geographic location), relative efficacy and toxicity.

Sézary Syndrome Presenting With Renal Involvement

Sézary syndrome is a rare aggressive leukemic variant of primary cutaneous T-cell lymphoma, typically presenting with erythroderma, lymphadenopathy, and an atypical clonal T-cell population. Though it often involves the spleen and liver, we report a case of Sézary syndrome with renal involvement that was treated successfully. Visceral involvement confers a poor prognosis requiring systemic treatment. The patient we describe was a 66-year-old man who was referred from Dermatology services for deteriorating kidney function. Polymerase chain reaction of genomic DNA from skin and kidney biopsies confirmed a clonal T-cell population matching a population isolated in peripheral blood. The patient was treated initially with alemtuzumab, which led to a significant improvement in kidney function, and he has subsequently received a successful allogeneic stem cell transplant. This case represents a rare cause of decreased kidney function and highlights the role of biopsy in patients with suspected Sézary syndrome.

Blood classification and blood response criteria in mycosis fungoides and Sézary syndrome using flow cytometry: recommendations from the EORTC cutaneous lymphoma task force

Our current mycosis fungoides (MF) and Sézary Syndrome (SS) staging system includes blood-classification from B0-B2 for patch/plaque/tumour or erythroderma based on manual Sézary counts but results from our EORTC survey confirm these are rarely performed in patch/plaque/tumour MF, and there is a trend towards using flow cytometry to measure blood-class. Accurately assigning blood-class effects overall stage and the 'global response' used to measure treatment responses in MF/SS and hence impacts management. The EORTC Cutaneous Lymphoma Task Force Committee have reviewed the literature and held a Workshop (June 2017) to agree a definition of blood-class according to flow cytometry. No large study comparing blood-class as defined by Sézary count with flow cytometry has been performed in MF/SS. The definition of blood-class by flow cytometry varies between publications. Low-level blood involvement occurs in patch/plaque/tumour much less than erythroderma (p < 0.001). The prognostic relevance of blood involvement (B1 or B2) in patch/plaque/tumour is not known. Studies have not shown a statistically worse difference in prognosis in erythrodermic MF patients with low-level blood involvement (IIIB) versus those without (IIIA), but Sezary patients who by definition have a leukaemic blood picture (staged IVA1 or higher) have a worse prognosis. For consistency flow, definition for blood-class must be an objective measurement. We propose absolute counts of either CD4+CD7-or CD4+CD26-where B0<250/μL, B1 = 250/μl-<1000/μL and B2≥1000/μL plus a T-cell blood clone. Fluctuations between B0 and B1 should not be considered in the treatment response criteria until further prognostic information is known.

The efficacy and safety of methotrexate versus interferon in cutaneous T-cell lymphomas

OBJECTIVES

Methotrexate (MTX) and interferon (IFN) have been used in the treatment of cutaneous T-cell lymphomas (CTCL) of various subtypes. We review our experience of MTX and IFN use in our patients with CTCL at a tertiary hospital.

MATERIALS AND METHODS

Medical records of patients over 4 years were reviewed. We describe the dosages, time to response, response rates, side effects, progression rate, and reasons for discontinuation.

RESULTS

Response rate was significantly higher in the IFN group than MTX group (86.67% and 47.4% respectively, p = .01). Disease progression occurred 57.89% in the MTX group whilst only 26.67% progressed with IFN therapy. Patients taking IFN therapy experienced proportionally more side effects of any type than those undertaking MTX treatment (86.67% vs. 47.37%, odds ratio 7.22). However, discontinuation rate in the IFN group (26.67%) was much lower than in the MTX arm (89.47%).

CONCLUSIONS

The most significant finding of this study was that patients with CTCL treated with IFN had a better response rate and significantly shorter response time compared with those treated with MTX. Additionally, patients had less disease progression on IFN than with MTX regardless of subtype of T-cell lymphoma and stage of disease.

Current systemic therapeutic options for advanced mycosis fungoides and Sézary syndrome

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most common cutaneous T-cell lymphomas (CTCLs). Both lack curative options, and advanced-stage carries a poor prognosis. Whilst there are a number of treatments available, achieving and maintaining a durable remission remains challenging. We review current systemic treatment options as monotherapy for advanced-stage MF (IIB-IV), appraising their mechanism of action, analyzing their efficacy, and describing toxicities. Individually, reported overall response rates (ORR) vary widely in the literature and duration of responses are typically short, ranging from 7.5 to 22.4 months. Combined therapy is frequently used in an effort to boost responses, although prospective studies comparing combinations to single agent therapies are rarely conducted. While recent translational research has led to increased understanding of the immunopathogenesis of MF and SS and the development of new treatments, current standard of care therapies are not curative and have low ORR for advanced-stage disease.