Chart review study of real-world clinical outcomes in patients with cutaneous T-cell lymphoma treated with extracorporeal photopheresis in the US in 2017-2019

BACKGROUND

Response rates of approved systemic therapies for cutaneous T-cell lymphoma (CTCL) hover near 30%, suggesting unmet need. This study describes real-world treatment patterns and response rates of extracorporeal photopheresis (ECP) in CTCL patients.

METHODS

A chart review was conducted in the United States of adults with CTCL who initiated ECP between January 1, 2017, and February 28, 2019, and received at least three months of ECP treatment as monotherapy or concomitant therapy. Clinical outcomes were collected quarterly for up to 18 months.

RESULTS

The 52 patients were predominantly Caucasian. Half were male; median age was 69 years. Most patients had Sézary syndrome (50%) or mycosis fungoides (36.5%). Nearly 40% of patients had stage IV disease; 33% had lymph node involvement. Nineteen patients (36.5%) achieved response (>50% reduction in BSA affected); median time to response was 6.5 months. The percentage of patients rated as at least minimally improved was 59.5% at 6 months (N = 22), 75.0% at 9 months (N = 24), and 60.0% at 12 months (N = 15) after ECP initiation.

CONCLUSIONS

Despite the ECP treated population in this study being older and having more advanced-stage disease than recent trials, response rates were comparable. These real-world findings support ECP as an effective treatment option for CTCL patients.

CASE OF THE TRANSFORMATION OF PSORIASIS INTO CUTANEOUS T-CELL LYMPHOMA

Psoriasis is a long-known skin pathology, the incidence of which is constantly rising, though it is not possible to clearly establish the trend due to the differences in the research design. In recent years, the number of cases among children and adolescents has increased. Psoriasis becomes more aggressive, severe forms are more common. It can be combined with other diseases but is rarely complicated. Isolated cases of the transformation of psoriatic plaques into skin cancer have already been described in the literature. Probable causes were the long-term use of photosensitizers and phototherapy, naphthalene, and tar. However, in general, the risk of the malignant recurrence in patients with psoriasis does not increase significantly. We present a clinical observation of the transformation of psoriasis into cutaneous T-cell lymphoma in a patient with more than 37 years of psoriasis experience, where on the background of typical psoriatic rashes, fungal growths of doughy consistency appeared, which were initially misinterpreted as a warty form of psoriasis. Based on the data of additional methods of examination and the results of histological examination, the diagnosis was clarified. Specific treatment was prescribed, which proved its effectiveness. The probable causes of degeneration, in our opinion, are prolonged irritating external therapy and excessive insolation.

Multi-omic profiling reveals the endogenous and neoplastic responses to immunotherapies in cutaneous T cell lymphoma

Cutaneous T cell lymphomas (CTCLs) are skin cancers with poor survival rates and limited treatments. While immunotherapies have shown some efficacy, the immunological consequences of administering immune-activating agents to CTCL patients have not been systematically characterized. We apply a suite of high-dimensional technologies to investigate the local, cellular, and systemic responses in CTCL patients receiving either mono- or combination anti-PD-1 plus interferon-gamma (IFN-γ) therapy. Neoplastic T cells display no evidence of activation after immunotherapy. IFN-γ induces muted endogenous immunological responses, while anti-PD-1 elicits broader changes, including increased abundance of CLA+CD39+ T cells. We develop an unbiased multi-omic profiling approach enabling discovery of immune modules stratifying patients. We identify an enrichment of activated regulatory CLA+CD39+ T cells in non-responders and activated cytotoxic CLA+CD39+ T cells in leukemic patients. Our results provide insights into the effects of immunotherapy in CTCL patients and a generalizable framework for multi-omic analysis of clinical trials.

Modulation of the skin microbiome in cutaneous T-cell lymphoma delays tumour growth and increases survival in the murine EL4 model

Cutaneous T-cell lymphomas (CTCL) are a group of lymphoproliferative disorders of skin-homing T cells causing chronic inflammation. These disorders cause impairment of the immune environment, which leads to severe infections and/or sepsis due to dysbiosis. In this study, we elucidated the host-microbial interaction in CTCL that occurs during the phototherapeutic treatment regime and determined whether modulation of the skin microbiota could beneficially affect the course of CTCL. EL4 T-cell lymphoma cells were intradermally grafted on the back of C57BL/6 mice. Animals were treated with conventional therapeutics such as psoralen + UVA (PUVA) or UVB in the presence or absence of topical antibiotic treatment (neomycin, bacitracin, and polymyxin B sulphate) as an adjuvant. Microbial colonisation of the skin was assessed to correlate with disease severity and tumour growth. Triple antibiotic treatment significantly delayed tumour occurrence (p = 0.026), which prolonged the survival of the mice (p = 0.033). Allocation to phototherapeutic agents PUVA, UVB, or none of these, along with antibiotic intervention, reduced the tumour growth significantly (p = 0.0327, p ≤ 0.0001, p ≤ 0.0001 respectively). The beta diversity indices calculated using the Bray-Curtis model showed that the microbial population significantly differed after antibiotic treatment (p = 0.001). Upon modulating the skin microbiome by antibiotic treatment, we saw an increase in commensal Clostridium species, e.g., Lachnospiraceae sp. (p = 0.0008), Ruminococcaceae sp. (p = 0.0001)., Blautia sp. (p = 0.007) and a significant reduction in facultative pathogens Corynebacterium sp. (p = 0.0009), Pelomonas sp. (p = 0.0306), Streptococcus sp. (p ≥ 0.0001), Pseudomonas sp. (p = 0.0358), and Cutibacterium sp. (p = 0.0237). Intriguingly, we observed a significant decrease in Staphylococcus aureus frequency (p = 0.0001) but an increase in the overall detection frequency of the Staphylococcus genus, indicating that antibiotic treatment helped regain the microbial balance and increased the number of non-pathogenic Staphylococcus populations. These study findings show that modulating microbiota by topical antibiotic treatment helps to restore microbial balance by diminishing the numbers of pathogenic microbes, which, in turn, reduces chronic inflammation, delays tumour growth, and increases survival rates in our CTCL model. These findings support the rationale to modulate the microbial milieu during the disease course of CTCL and indicate its therapeutic potential.

Naturally occurring T cell mutations enhance engineered T cell therapies

Adoptive T cell therapies have produced exceptional responses in a subset of patients with cancer. However, therapeutic efficacy can be hindered by poor T cell persistence and function1. In human T cell cancers, evolution of the disease positively selects for mutations that improve fitness of T cells in challenging situations analogous to those faced by therapeutic T cells. Therefore, we reasoned that these mutations could be co-opted to improve T cell therapies. Here we systematically screened the effects of 71 mutations from T cell neoplasms on T cell signalling, cytokine production and in vivo persistence in tumours. We identify a gene fusion, CARD11-PIK3R3, found in a CD4+ cutaneous T cell lymphoma2, that augments CARD11-BCL10-MALT1 complex signalling and anti-tumour efficacy of therapeutic T cells in several immunotherapy-refractory models in an antigen-dependent manner. Underscoring its potential to be deployed safely, CARD11-PIK3R3-expressing cells were followed up to 418 days after T cell transfer in vivo without evidence of malignant transformation. Collectively, our results indicate that exploiting naturally occurring mutations represents a promising approach to explore the extremes of T cell biology and discover how solutions derived from evolution of malignant T cells can improve a broad range of T cell therapies.

Cost of Treating Cutaneous T-Cell Lymphoma in Spain: Analysis of MICADOS Study Data by Disease Stage

BACKGROUND AND OBJECTIVE

The cost of treating cutaneous T-cell lymphoma (CTCL) in Spain is unknown. With the advent of new treatments, it is more important than ever to gain an accurate picture of the true costs involved. The MICADOS study had 2 primary objectives: 1)to evaluate the impact of CTCL on patient quality of life, and 2)to evaluate the costs associated with the disease. This article reports the results of the cost analysis.

METHODS

We estimated the cost of treating CTCL over a period of 1year from the perspective of the Spanish National Health System. Twenty-three dermatologists and hematologists from 15 public hospitals analyzed data for adult patients with mycosis fungoides (MF) or Sézary syndrome (SS).

RESULTS

A total of 141 patients (57.4% male) with a mean age of 63.6 years (95%CI: 61.4-65.7 years) were included. The mean direct annual cost of treating CTCL was €34,214 per patient. The corresponding costs by stage were €11,952.47 for stageI disease, €23,506.21 for stageII disease, €38,771.81 for stageIII disease, and €72,748.84 for stageIV disease. The total direct annual cost of treating MF/SS in public hospitals in Spain was estimated at €78,301,171; stageI disease accounted for 81% of all costs, stageII for 7%, and stagesIII andIV for 6% each.

CONCLUSIONS

The MICADOS study offers an accurate picture of the direct cost of treating CTCL in patients with MF/SS in Spain and shows that costs vary significantly according to disease stage. Patient-borne and indirect costs should be analyzed in future studies.

[Translated article] Cost of Treating Cutaneous T-Cell Lymphoma in Spain: Analysis of MICADOS Study Data by Disease Stage

BACKGROUND AND OBJECTIVE

The cost of treating cutaneous T-cell lymphoma (CTCL) in Spain is unknown. With the advent of new treatments, it is more important than ever to gain an accurate picture of the true costs involved. The MICADOS study had 2 primary objectives: 1)to evaluate the impact of CTCL on patient quality of life, and 2)to evaluate the costs associated with the disease. This article reports the results of the cost analysis.

METHODS

We estimated the cost of treating CTCL over a period of 1year from the perspective of the Spanish National Health System. Twenty-three dermatologists and hematologists from 15 public hospitals analyzed data for adult patients with mycosis fungoides (MF) or Sézary syndrome (SS).

RESULTS

A total of 141 patients (57.4% male) with a mean age of 63.6 years (95%CI: 61.4-65.7 years) were included. The mean direct annual cost of treating CTCL was €34,214 per patient. The corresponding costs by stage were €11,952.47 for stageI disease, €23,506.21 for stageII disease, €38,771.81 for stageIII disease, and €72,748.84 for stageIV disease. The total direct annual cost of treating MF/SS in public hospitals in Spain was estimated at €78,301,171; stageI disease accounted for 81% of all costs, stageII for 7%, and stagesIII andIV for 6% each.

CONCLUSIONS

The MICADOS study offers an accurate picture of the direct cost of treating CTCL in patients with MF/SS in Spain and shows that costs vary significantly according to disease stage. Patient-borne and indirect costs should be analyzed in future studies.

Allogeneic transplantation and cellular therapies in cutaneous T-cell lymphoma

INTRODUCTION

Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common types of cutaneous T-cell lymphoma. Although many available treatments offer temporary disease control, allogeneic hematopoietic stem cell transplant (allo-HSCT) is the only curative treatment option for advanced stage MF and SS. CAR T-cell therapy is a promising new avenue for treatment.

AREAS COVERED

In this review, we discuss the evidence supporting the use of allo-HSCT for the treatment of MF/SS, including disease status at the time of transplant, conditioning regimen, total body irradiation (TBI), and donor lymphocyte infusion (DLI). We also address the potential role for CAR T-cell therapy in CTCL.

EXPERT OPINION

Allo-HSCT is an effective treatment for patients with advanced MF and SS. However, significant research is required to determine optimal treatment protocols. Data support the use of reduced-intensity conditioning regimens and suggests that the use of TBI for debulking of skin disease may result in more durable remissions. Donor lymphocyte infusions (DLI) appear to be particularly effective in inducing complete remission in MF/SS patients with relapsed or residual disease. Challenges with CAR-T therapies in T-cell lymphoma include T-cell fratricide due to shared antigens on malignant and nonmalignant T-cells, penetrance into the skin compartment, and CAR-T cell persistence.

Early intervention of extracorporeal photopheresis for advancing/progressing cutaneous T-cell lymphoma

Patients with cutaneous T-cell lymphoma with progressive disease typically undergo a series of skin-directed and systemic therapy regimens during cycles of response and relapse. Extracorporeal photopheresis (ECP) is an effective and safe systemic treatment option, often reserved for later stages of disease and typically employed after failure of several other therapies. ECP has benefits in response rate, time to next treatment, and tolerability that may support its use earlier in the treatment cycle for advancing/progressing disease.

Cutaneous T-cell Lymphomas: A Single-center Retrospective Analysis

INTRODUCTION

Cutaneous T-cell lymphomas (CTCLs) are rare diseases characterized by infiltration of malignant T-cells into the skin. We evaluated the prevalence, epidemiology, and therapy of CTCLs, focusing on its most well-known subtypes, namely mycosis fungoides (MF) and Sézary syndrome (SS).

PATIENTS AND METHODS

We retrospectively analyzed the medical data of patients with a histologically confirmed diagnosis of CTCL presenting to our outpatient department during a 5-year period from January 2015 to December 2019.

RESULTS

We evaluated the files of 102 patients, of whom 67% were men and 33% women. The overall mean age was 59.1±14.1 (24-86) years. Ninety-two patients (90%) were diagnosed with MF and ten patients (10%) with SS. According to ISCL/EORTC, the majority of patients initially classified as stage IA (34%) and IB (45%). Disease frequency decreased at advanced stages (II: 4%; III: 7%; IV: 10%). Forty-five patients (44.1%) received only skin-directed therapy (SDT). Twenty patients (19.6%) progressed from SDT to systemic therapy (ST). Thirty-seven patients (36.3%) received ST combined with SDT (TS) from the start of treatment. Overall, fifty different therapeutic approaches of TS were initiated due to lack of response to therapy or disease progression.

CONCLUSION

Management of CTCLs aims to maintain patient quality of life while minimizing side-effects. As CTCLs are usually incurable diseases, the focus of treatment is on symptom control and prevention of disease progression. Due to the large patient group and the long observation period, our study allows for a valid evaluation of the frequency and therapy of MF and SS in a university outpatient clinic in Germany. We favor topical therapies in early stages with more invasive therapies in advanced stages.

Cutaneous T-cell lymphoma with CNS involvement: a case series and review of the literature

Cutaneous T-cell lymphoma (CTCL) is a rare hematologic malignancy that traditionally presents with cutaneous lesions, though metastases are not uncommon in progressive disease. We describe four cases of CTCL with central nervous system (CNS) involvement, detailing the history, pathological characteristics, treatment response, and progression. Median time from initial diagnosis to CNS metastasis was ∼5.4 years (range 3.4-15.5 years) and survival after metastasis was ∼160 days (range 19 days-4.4 years). No patients achieved long-term (>5 years) survival, though some displayed varying degrees of remission following CNS-directed therapy. We conclude that clinicians must be attentive to the development of CNS metastases in patients with CTCL. The growing body of literature on such cases will inform evolving therapeutic guidelines on this rare CTCL complication.

Descriptive Analysis and Factors Influencing Survival in Patients With Primary Cutaneous Gamma-Delta T Cell Lymphoma. A Retrospective National Cancer Database Study

BACKGROUND

Gamma delta T cells gives rise to a rare malignancy called Primary cutaneous Gamma-Delta T cell lymphoma (PCGDTCL).

METHODS

From the National Cancer Database (NCDB), 110 (0.015%) patients with PCGDTCL were identified.

RESULTS

Males aged >60 years were the commonest cohort. Caucasian race was the most common (Caucasian: 79.09%, African American:16.36%). Most patients were diagnosed at stage 1 (52.33%), followed by stage 4 (30.23%). On analyzing income categories, <$48,000 group had 48.15% stage 4 (13/27) and 40.74% (11/27) stage 1. Overall survival (OS) of the study group at 3 years by Kaplan-Meier (KM) analysis was 46.6%. African American race (37.5%), income of <$48,000 (27.6%) and government insurance (38.8%) had lower survival rates in KM analysis. In the adjusted hazard ratio (HR) analysis, only age <=40 years compared to >60 years (0.165 [0.036, 0.768], P= .0217) reached significance. Although the group that did not receive any chemotherapy or radiation seemed to have a better survival by KM analysis at 74.3% at 3 years, significance was not seen in the adjusted HR estimates and majority of the patients in this group were stage 1. This group may have received topical treatments which may have not been captured in NCDB. Adjusted analysis also revealed chemoradiation to have a lower mortality risk compared to chemotherapy alone (0.229 [0.079, 0.670], P = .0071), suggesting that aggressive strategies may be required for management when needed.

CONCLUSION

Socioeconomic disparities significantly impact access to healthcare and are of particular importance in rare lymphomas.

Mycosis fungoides with spongiosis: a case report

BACKGROUND

Mycosis fungoides (MF) is the most common form of cutaneous T-cell lymphoma (CTCL). CTCL are an uncommon, heterogeneous group of non-Hodgkin lymphomas (NHLs) of T- and B-cell origin where the skin is the primary organ of involvement. It is characterized by malignant CD4+ T-cells infiltrating the skin and other organs, leading to progressive skin and systemic involvement. Histopathologically, MF is characterized by atypical lymphocytes demonstrating epidermotropism without spongiosis. Spongiosis is the histological hallmark of intercellular epidermal edema, viewed as clear spaces within the epidermis, and is very common in benign inflammatory dermatoses. Very few studies have reported MF in sub-Saharan Africa (SSA). We are reporting a case of MF with a rare presentation of spongiosis treated successfully with a low dose total skin electron beam therapy (TSEBT) followed by maintenance therapy of low dose Methotrexate (MT) at the Ocean Road Cancer Institute (ORCI) in Tanzania. This is the first case of MF to be managed with low-dose TSEBT in Tanzania. The authors wish to create awareness of the disease among physicians and pathologists and expand on the data paucity in SSA.

CASE DESCRIPTION

We are reporting a case of a 31-year-old male of African origin who self-referred to our oncology center with a 4-year history of skin rashes throughout the body, which was unresponsive to topical steroid treatment. The biopsy was taken, and the patient was diagnosed with MF CD 3 positive with spongiosis. The patient was treated with radiotherapy, whereby he received low dose total skin electron beam therapy (TSEBT) 12 Gy in 3 fractions at a daily dose of 4 Gy, followed by maintenance therapy of low dose Methotrexate and attained an excellent therapeutic response.

CONCLUSION

Spongiosis is an infrequent presentation of MF. Low-dose TSEBT provides reliable and rapid reduction of disease burden in patients with MF, which could be administered safely multiple times during a patient's disease with an acceptable toxicity profile. Lack of tendency to perform skin biopsies and cost constraints in assessing multiple immunophenotypic markers lead to missing the diagnosis. Diagnosis and treatment of MF in resource-limited countries is challenging.

Mode of action, indications and recommendations on extracorporeal photopheresis (ECP)

Extracorporeal photopheresis (ECP) has gained importance in the treatment of several diseases. Initially introduced as a new therapeutic modality for the treatment of patients with cutaneous T-cell lymphoma, the indications for the use of ECP have expanded to include hematology and transplantation immunology. Extracorporeal photopheresis has found its place in the treatment plan of cutaneous T-cell lymphoma, systemic sclerosis, graft-versus-host disease, organ transplantation such as heart and lung, sometimes as first-line therapy and very often in combination with various systemic immunosuppressive therapies. The procedure basically consists of three steps: leukapheresis, photoactivation and reinfusion. The following article presents possible theories about the mechanism of action, which is not yet fully understood, and discusses the five most common indications for ECP treatment with corresponding therapy recommendations.

What Is New in Cutaneous T Cell Lymphoma?

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

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.

Characterizing Outcomes in Visceral Cutaneous T-Cell Lymphoma: A Single Center Retrospective Study

INTRODUCTION

Visceral involvement of cutaneous T-cell lymphoma (vCTCL) is a rare but poorly studied complication of CTCL. We aimed to assess clinical characteristics, treatment, and outcomes, associated with vCTCL at our institution.

METHODS

We conducted a retrospective review of patients with vCTCL among patients with a confirmed histopathologic diagnosis of CTCL seen at the Winship Cancer Institute in Emory University. vCTCL was defined as a highest TNMB stage of 4B with extracutaneous metastatic disease (M1) pathologically confirmed or strongly clinically suspected based on imaging, symptoms, and the clinical judgment of the treating physician. Patients were selected from our CTCL database containing 656 patients from 1990 to 2022. Clinical characteristics were characterized. Clinical outcomes were measured as overall survival (OS) and progression-free survival (PFS) using Kaplan-Meier curve and univariable Cox regression analysis.

RESULTS

Twenty-six of 656 patients with vCTCL were identified. 42.3% of patients were black. Twenty-two patients were diagnosed with MF/SS and 4 had other CTCL subtypes including pcALCL, Gamma-Delta, and Cytotoxic T-Cell Lymphoma. The median PFS and OS were 7.3 months (3.8, 11) and 12.1 months (9.9, 18.2), respectively. Median time to metastasis from initial diagnosis was 12.1 months. The most common M1 sites were liver (19.2%) and lung (42.3%). M1 sites outside of liver or lung were associated with inferior OS (HR 8.9, 95%CI: 2.7-29.5, P-value <.001) and PFS (HR 4.3, 95%CI: 1.44-12.7, P-value = .009). No treatments or baseline factors were associated with improved survival.

CONCLUSION

Our retrospective study confirms therapy resistance and dismal outcomes among patients with vCTCL.

Primary cutaneous lymphomas: exploration of 10-year data from supraregional mutlidisciplinary team meetings in Glasgow, UK

Primary cutaneous lymphomas (PCLs) are non-Hodgkin lymphomas, presenting in the skin. They are classified into cutaneous B-cell lymphomas (CBCLs) or cutaneous T-cell lymphomas (CTCLs). The most common CTCL subtypes are mycosis fungoides (MF) and Sézary syndrome (SS). All patient's cases should be discussed at a specialist multidisciplinary team (MDT) meeting. This is the first published review, to our knowledge, of PCL MDT case discussion in the UK. Patient cases between 2008 and 2019 were reviewed to assess: frequency of PCL subtype, documentation of CTCL staging and management of MF/SS. Of 356, 103 (29%) were CBCLs and the majority (n = 200, 56%) were CTCLs. MF/SS was the diagnosis in 120 (34%). Staging was documented in 44% (n = 53) of patients with MF/SS. Management largely followed guidelines for MF/SS, topical corticosteroids were the most common treatment (n = 93, 78%). Frequency of PCL subtype is largely comparable with previously published data. Documentation of CTCL staging is low, but higher than other reports. Our work begins to address the gap in real-world data on CTCLs. A standardized approach to data collection would inform clinical practice.

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

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

Epidemiology of cutaneous T-cell lymphomas: state of the art and a focus on the Italian Marche region

Among primary cutaneous T-cell lymphomas (CTCL), mycosis fungoides (MF) is the most frequent and, along with Sézary syndrome (SS), the best-studied subtype. Most available studies on epidemiology of MF and SS are based on small cohorts or different inclusion criteria. Moreover, although this has become a hot topic, most studies show limitations, such as selection bias and lack of clinical information or follow-up data. Therefore, no reliable conclusions can be drawn. This paper reviews the current data underpinning our understanding of the epidemiology of MF and SS, and presents some original findings based on data retrieved from the cutaneous lymphoma registry of the Italian Marche region. The Marche Regional Cutaneous Lymphoma Registry is a multidisciplinary team founded 27 years ago to share the management of these rare disorders. All patients with a clinical and histologically confirmed diagnosis of primary cutaneous lymphoma are centralized in Ancona (Italy) at the Haematology Clinic, Polytechnic University of Marche, for clinical evaluation, staging, treatment, and follow-up. This paper emphasizes the need for a national registry of pCLs in Italy, as no detailed epidemiological information is available in the country except for the Marche Regional Cutaneous Lymphoma Registry. A national registry would allow for more comprehensive data collection from all over Italy and could provide more accurate information on incidence and epidemiology. This would be beneficial for understanding the pathogenesis and diagnostic procedures of these diseases and could improve patient outcomes. Therefore, we advise the creation of a national registry of pCLs in Italy.