Maintenance therapy for CTCL: importance for prevention of disease progression.

There are no established maintenance protocols for cutaneous lymphomas. We aim to determine patient treatments and outcomes during the COVID-19 pandemic in order to uncover the most effective maintenance protocols for cutaneous lymphomas and impact of treatment interruption. Data was collected retrospectively from nine international institutions, including 149 patients. Younger patients had earlier stages of disease and were most frequently treated with skin-directed therapies including topical steroids, mechlorethamine gel, and phototherapy. Treatment interruption varied by treatment type and stage, with patients on topical therapies and earlier stages of disease being least likely to experience interruption. Treatment interruption was significantly associated with progression of disease and worse outcomes, with twice as many patients progressing who had interruption compared to those without interruption. This study may demonstrate the significance of continuous maintenance therapies, even in younger patients with early stages of disease.

Unleashed monocytic engagement in Sézary syndrome during the combination of anti-CCR4 antibody with type I interferon.

ABSTRACT: Sézary syndrome (SS) is an aggressive leukemic expansion of skin-derived malignant CD4+ T cells. Drug monotherapy often results in disease relapse because of the heterogenous nature of malignant CD4+ T cells, but how therapies can be optimally combined remains unclear because of limitations in understanding the disease pathogenesis. We identified immunologic transitions that interlink mycosis fungoides with SS using single-cell transcriptome analysis in parallel with high-throughput T-cell receptor sequencing. Nascent peripheral CD4+ T cells acquired a distinct profile of transcription factors and trafficking receptors that gave rise to antigenically mature Sézary cells. The emergence of malignant CD4+ T cells coincided with the accumulation of dysfunctional monocytes with impaired fragment crystallizable γ-dependent phagocytosis, decreased responsiveness to cytokine stimulation, and limited repertoire of intercellular interactions with Sézary cells. Type I interferon supplementation when combined with a monoclonal antibody targeting the chemokine receptor type 4 (CCR4), unleashed monocyte induced phagocytosis and eradication of Sézary cells in vitro. In turn, coadministration of interferon-α with the US Food and Drug Administration-approved anti-CCR4 antibody, mogamulizumab, in patients with SS induced marked depletion of peripheral malignant CD4+ T cells. Importantly, residual CD4+ T cells after Sézary cell ablation lacked any immunologic shifts. These findings collectively unveil an auxiliary role for augmenting monocytic activity during mogamulizumab therapy in the treatment of SS and underscore the importance of targeted combination therapy in this disease.

Utility of Low-Dose Duvelisib for Advanced Mycosis Fungoides: A Single-Institution Study.

Duvelisib, a small-molecule phosphatidylinositol 3-kinase-δ,γ inhibitor, has shown efficacy for mycosis fungoides (MF) at dosage ranges of 25-100 mg twice daily (BID), but with significant toxicity. We conducted a retrospective cohort study of patients with advanced MF treated with low-dose duvelisib (15 mg every other day to BID), in an effort to minimize toxicity. A total of 7 patients were included. The overall response rate on duvelisib was 71%, with the remaining patients maintaining stable disease. Mean modified Severity Weighted Assessment Tool score improved by 57.4% and mean percent body surface area involved improved by 52%. Median progression-free survival was 10.3 months. Adverse events occurred in 4 of 7 patients, the most common being fatigue (2/7; grades 1-2), nausea (2/7; grades 1-2), and transaminitis (2/7; grade 3). Overall, low-dose duvelisib showed efficacy for advanced MF with less toxicity, providing a rationale for its use as monotherapy and potentially combinatorial therapy.

Deciphering Tumor Cell Evolution in Cutaneous T-Cell Lymphomas: Distinct Differentiation Trajectories in Mycosis Fungoides and Sézary Syndrome.

Cutaneous T-cell lymphomas are a heterogeneous group of neoplasms originating in the skin, with mycosis fungoides (MF) and Sézary syndrome (SS) representing the most common variants. The cellular origin of cutaneous lymphomas has remained controversial owing to their immense phenotypic heterogeneity that obfuscates lineage reconstruction on the basis of classical surface biomarkers. To overcome this heterogeneity and reconstruct the differentiation trajectory of malignant cells in MF and SS, TCR sequencing was performed in parallel with targeted transcriptomics at the single-cell resolution among cutaneous samples in MF and SS. Unsupervised lineage reconstruction showed that Sézary cells exist as a population of CD4+ T cells distinct from those in patch, plaque, and tumor MF. Further investigation of malignant cell heterogeneity in SS showed that Sézary cells phenotypically comprised at least 3 subsets on the basis of differential proliferation potentials and expression of exhaustion markers. A T helper 1-polarized cell type, intermediate cell type, and exhausted T helper 2-polarized cell type were identified, with T helper 1- and T helper 2-polarized cells displaying divergent proliferation potentials. Collectively, these findings provide evidence to clarify the relationship between MF and SS and reveal cell subsets in SS that suggest a possible mechanism for therapeutic resistance.

What Does the Future Hold for Biomarkers of Response to Extracorporeal Photopheresis for Mycosis Fungoides and Sézary Syndrome?

Extracorporeal photopheresis (ECP) is an FDA-approved immunotherapy for cutaneous T-cell lymphoma, which can provide a complete response in some patients. However, it is still being determined who will respond well, and predictive biomarkers are urgently needed to target patients for timely treatment and to monitor their response over time. The aim of this review is to analyze the current state of the diagnostic, prognostic, and disease state-monitoring biomarkers of ECP, and outline the future direction of the ECP biomarker discovery. Specifically, we focus on biomarkers of response to ECP in mycosis fungoides and Sézary syndrome. The review summarizes the current knowledge of ECP biomarkers, including their limitations and potential applications, and identifies key challenges in ECP biomarker discovery. In addition, we discuss emerging technologies that could revolutionize ECP biomarker discovery and accelerate the translation of biomarker research into clinical practice. This review will interest researchers and clinicians seeking to optimize ECP therapy for cutaneous T-cell lymphoma.

CD5+ Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type, Presenting as an Asymptomatic Nodule.

Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT), is a rare and aggressive variant of primary cutaneous lymphoma that typically expresses B cells as well as MUM1/IRF4, BCL2, and FOXP1, whereas BCL6 may be present or undetectable. We present a case of CD5+ PCDLBCL-LT presenting as a 6 mm pink-bluish nodule on the mid-left thigh, which was concerning for basal cell carcinoma. The histological examination reveals the presence of an intradermal proliferation of large, atypical CD5+, CD20+ BCL2+, BCL6+, MUM-1+, and Cyclin-D1+ lymphocytes in a nodular, diffuse interstitial and perivascular distribution. Because the patient presented with a small, single nodule, the systemic treatment of multiagent chemotherapy was avoided and localized electron beam radiation therapy with rituximab was initiated instead, achieving complete response. Early identification of PCDLBCL-LT is key for maximal therapeutic benefit and prognosis; it is important to consider PCDLBCL-LT on the differential when evaluating small, single nodules on the lower extremities of elderly patients.

Blockade of the Immune Checkpoint CD47 by TTI-621 Potentiates the Response to Anti-PD-L1 in Cutaneous T-Cell Lymphoma.

Cutaneous T-cell lymphoma (CTCL) is an incurable and cosmetically disfiguring disease associated with microenvironmental signals. We investigated the effects of CD47 and PD-L1 immune checkpoint blockades, as a strategy for targeting both innate and adaptive immunity. CIBERSORT analysis identified the immune-cell composition in the CTCL tumor microenvironment and the immune checkpoint expression profile for each immune-cell gene cluster from CTCL lesions. We investigated the relationship between MYC and CD47 and PD-L1 expression and found that MYC short hairpin RNA knockdown and MYC functional suppression by TTI-621 (SIRPαFc) and anti-PD-L1 (durvalumab) in CTCL cell lines reduced the expression of CD47 and PDL1 mRNA and protein as measured by qPCR and flow cytometry, respectively. In vitro, blockade of the CD47-SIRPα interaction with TTI-621 increased the phagocytic activity of macrophages against CTCL cells and enhanced CD8+ T-cell-mediated killing in a mixed leucocyte reaction. Moreover, TTI-621 synergized with anti-PD-L1 in macrophages reprogram to M1-like phenotypes and inhibited CTCL cell growth. These effects were mediated by cell death-related pathways, including apoptosis, autophagy, and necroptosis. Collectively, our findings show that CD47 and PD-L1 are critical regulators of immune surveillance in CTCL and that dual targeting of CD47 and PD-L1 will provide insight into tumor immunotherapy for CTCL.

Targeting the CD47-SIRPα Axis: Present Therapies and the Future for Cutaneous T-cell Lymphoma.

The loss of CD47 on aging cells serves as a signal to macrophages to eliminate the target. Therefore, CD47 is a "do-not-eat-me" sign preventing macrophagal phagocytosis via interaction with its ligand SIRPα. Malignant lymphocytes of mycosis fungoides and Sézary syndrome express CD47 highly, thus, being ideal candidates for targeted anti-CD47 therapies. The classes of current anti-CD47-SIRPα therapeutic molecules present in a large variety and include monoclonal antibodies against CD47 and SIRPα, bioengineered SIRPα proteins, miRNAs, and bispecific antibodies. We provided a detailed analysis of all available investigational drugs in a contest of cutaneous T-cell lymphoma. A combination of blockade of the CD47-SIRPα axis and secondary targets in the tumor microenvironment (TME) may improve the clinical efficacy of current immunotherapeutic approaches. We evaluated the possible combination and outlined the most promising one.

Factors associated with treatment satisfaction in patients with hidradenitis suppurativa: results from the Global VOICE project.

BACKGROUND: Nearly half of patients with hidradenitis suppurativa (HS) report dissatisfaction with their treatment. However, factors related to treatment satisfaction have not been explored. OBJECTIVES: To measure associations between treatment satisfaction and clinical and treatment-related characteristics among patients with HS. METHODS: Treatment satisfaction was evaluated utilizing data from a cross-sectional global survey of patients with HS recruited from 27 institutions, mainly HS referral centres, in 14 different countries from October 2017 to July 2018. The primary outcome was patients' self-reported overall satisfaction with their current treatments for HS, rated on a five-point scale from 'very dissatisfied' to 'very satisfied'. RESULTS: The final analysis cohort comprised 1418 patients with HS, most of whom were European (55%, 780 of 1418) or North American (38%, 542 of 1418), and female (85%, 1210 of 1418). Overall, 45% (640 of 1418) of participants were either dissatisfied or very dissatisfied with their current medical treatment. In adjusted analysis, patients primarily treated by a dermatologist for HS had 1·99 [95% confidence interval (CI) 1·62-2·44, P < 0·001] times the odds of being satisfied with current treatment than participants not primarily treated by a dermatologist. Treatment with biologics was associated with higher satisfaction [odds ratio (OR) 2·36, 95% CI 1·74-3·19, P < 0·001] relative to treatment with nonbiologic systemic medications. Factors associated with lower treatment satisfaction included smoking (OR 0·78, 95% CI 0·62-0·99; active vs. never), depression (OR 0·69, 95% CI 0·54-0·87), increasing number of comorbidities (OR 0·88 per comorbidity, 95% CI 0·81-0·96) and increasing flare frequency. CONCLUSIONS: There are several factors that appear to positively influence satisfaction with treatment among patients with HS, including treatment by a dermatologist and treatment with a biologic medication. Factors that appear to lower treatment satisfaction include active smoking, depression, accumulation of comorbid conditions and increasing flare frequency. Awareness of these factors may support partnered decision making with the goal of improving treatment outcomes. What is already known about this topic? Nearly half of patients with hidradenitis suppurativa report dissatisfaction with their treatments. What does this study add? Satisfaction with treatment is increased by receiving care from a dermatologist and treatment with biologics. Satisfaction with treatment is decreased by tobacco smoking, accumulation of comorbid conditions including depression, and higher flare frequency. What are the clinical implications of this work? Awareness of the identified factors associated with poor treatment satisfaction may support partnered decision making and improve treatment outcomes.

Efficacy and Safety of Topical Hypericin Photodynamic Therapy for Early-Stage Cutaneous T-Cell Lymphoma (Mycosis Fungoides): The FLASH Phase 3 Randomized Clinical Trial.

Importance: Given that mycosis fungoides-cutaneous T-cell lymphoma (MF/CTCL) is chronic, there is a need for additional therapies with minimal short- and long-term adverse effects. Topical synthetic hypericin ointment, 0.25%, activated with visible light is a novel, nonmutagenic photodynamic therapy (PDT). Objectives: To determine the efficacy and safety of topical synthetic hypericin ointment, 0.25%, activated with visible light as a nonmutagenic PDT in early-stage MF/CTCL. Design, Settings, and Participants: This was a multicenter, placebo-controlled, double-blinded, phase 3 randomized clinical trial (FLASH study) conducted from December 2015 to November 2020 at 39 academic and community-based US medical centers. Participants were adults (≥18 years) with early-stage (IA-IIA) MF/CTCL. Interventions: In cycle 1, patients were randomized 2:1 to receive hypericin or placebo to 3 index lesions twice weekly for 6 weeks. In cycle 2, all patients received the active drug for 6 weeks to index lesions. In cycle 3 (optional), both index and additional lesions received active drug for 6 weeks. Main Outcomes and Measures: The primary end point was index lesion response rate (ILRR), defined as 50% or greater improvement in modified Composite Assessment of Index Lesion Severity (mCAILS) score from baseline after 6 weeks of therapy for cycle 1. For cycles 2 and 3, open label response rates were secondary end points. Adverse events (AEs) were assessed at each treatment visit, after each cycle, and then monthly for 6 months. Data analyses were performed on December 21, 2020. Results: The study population comprised 169 patients (mean [SD] age, 58.4 [16.0] years; 96 [57.8%] men; 120 [72.3%] White individuals) with early-stage MF/CTCL. After 6 weeks of treatment, hypericin PDT was more effective than placebo (cycle 1 ILRR, 16% vs 4%; P = .04). The ILRR increased to 40% in patients who received 2 cycles of hypericin PDT (P < .001 vs cycle 1 hypericin) and to 49% after 3 cycles (P < .001 vs cycle 1 hypericin). Significant clinical responses were observed in both patch and plaque type lesions and were similar regardless of age, sex, race, stage IA vs IB, time since diagnosis, and number of prior therapies. The most common treatment-related AEs were mild local skin (13.5%-17.3% across cycles 1-3 vs 10.5% for placebo in cycle 1) and application-site reactions (3.2%-6.9% across cycles 1-3 vs 4% for placebo in cycle 1). No drug-related serious AEs occurred. Conclusion and Relevance: The findings of this randomized clinical trial indicate that synthetic hypericin PDT is effective in early-stage patch and plaque MF/CTCL and has a favorable safety profile. Trial Registration: ClinicalTrials.gov Identifier: NCT02448381.

Understanding Cell Lines, Patient-Derived Xenograft and Genetically Engineered Mouse Models Used to Study Cutaneous T-Cell Lymphoma.

Cutaneous T cell lymphoma (CTCL) is a spectrum of lymphoproliferative disorders caused by the infiltration of malignant T cells into the skin. The most common variants of CTCL include mycosis fungoides (MF), Sézary syndrome (SS) and CD30+ Lymphoproliferative disorders (CD30+ LPDs). CD30+ LPDs include primary cutaneous anaplastic large cell lymphoma (pcALCL), lymphomatoid papulosis (LyP) and borderline CD30+ LPD. The frequency of MF, SS and CD30+ LPDs is ~40-50%, <5% and ~10-25%, respectively. Despite recent advances, CTCL remains challenging to diagnose. The mechanism of CTCL carcinogenesis still remains to be fully elucidated. Hence, experiments in patient-derived cell lines and xenografts/genetically engineered mouse models (GEMMs) are critical to advance our understanding of disease pathogenesis. To enable this, understanding the intricacies and limitations of each individual model system is highly important. Presently, 11 immortalized patient-derived cell lines and different xenograft/GEMMs are being used to study the pathogenesis of CTCL and evaluate the therapeutic efficacy of various treatment modalities prior to clinical trials. Gene expression studies, and the karyotyping analyses of cell lines demonstrated that the molecular profile of SeAx, Sez4, SZ4, H9 and Hut78 is consistent with SS origin; MyLa and HH resemble the molecular profile of advanced MF, while Mac2A and PB2B represent CD30+ LPDs. Molecular analysis of the other two frequently used Human T-Cell Lymphotropic Virus-1 (HTLV-1)+ cell lines, MJ and Hut102, were found to have characteristics of Adult T-cell Leukemia/Lymphoma (ATLL). Studies in mouse models demonstrated that xenograft tumors could be grown using MyLa, HH, H9, Hut78, PB2B and SZ4 cells in NSG (NOD Scid gamma mouse) mice, while several additional experimental GEMMs were established to study the pathogenesis, effect of drugs and inflammatory cytokines in CTCL. The current review summarizes cell lines and xenograft/GEMMs used to study and understand the etiology and heterogeneity of CTCL.

Exhausted Markers in Cutaneous T-Cell Lymphoma: The Face that Launched a Thousand Ships.

Immune-modulatory therapies are widely appreciated to rejuvenate host antitumor immunity and improve mortality in solid-organ cancers. Targeting the exhausted markers such as PD-1, CTLA4, TIM3, LAG3 are particularly attractive owing to the activation of the immune response. However, their role in cutaneous T-cell lymphomas is less defined owing to the expression of those exhausted markers on both nonmalignant and malignant lymphocytes. In a new article of the Journal of Investigative Dermatology, Han et al. (2021) showed that microRNAs in malignant T cells could regulate the expression of PD-1, CTLA4, TIM3, and LAG3 and simultaneously mediate evasion from immune surveillance. These findings get us one step closer in our further investigation of whether those molecules could be targeted therapeutically.

Repetitive expanded T-cell receptor clonotypes impart the classic T helper 2 Sézary cell phenotype.

Six out of 12 Sézary patients shared one clonotype (TRAV13-1*01-TRAJ49*01-TRBV20-1*01-TRBJ2-3*01). TRBV20-1*01 (also known as Vb2) that binds toxic shock syndrome toxin-1 was utilized by Sézary cells among half of the cohort, which would be expected for a common unifying origin.