Durable loss of a malignant T-cell clone in a stage IV cutaneous T-cell lymphoma patient treated with high-dose interferon and photopheresis

Clinical manifestations and pathogenesis of cutaneous lymphomas: current status and future directions

The primary cutaneous lymphomas are a heterogeneous group of T-, Natural Killer- and B- cell neoplasms with a wide range of clinical and pathological presentations, and with very different prognoses compared to systemic lymphomas. Recent studies have shown that the skin microenvironment, which is composed of various immune cell subsets as well as their spatial distribution and T-cell interactions through different chemokines and cytokines, has an important role in the development and pathogenesis of cutaneous lymphomas and has assisted in the development of novel and more effective immunotherapies. The following review will focus on the major subtypes of primary cutaneous lymphomas, including the clinical and histological patterns, molecular hallmarks, and current and future treatment strategies.

The Use of Interferons in the Treatment of Cutaneous T-Cell Lymphoma

Interferons are polypeptides that naturally occur in the human body as a part of the innate immune response. By harnessing these immunomodulatory functions, synthetic interferons have shown efficacy in combating various diseases including cutaneous T-cell lymphoma. This article closely examines the qualities of interferon alfa and interferon gamma and the evidence behind their use in the 2 most common types of cutaneous T-cell lymphomas, namely, mycosis fungoides and Sézary syndrome.

Primary cutaneous T-cell lymphoma (mycosis fungoides and Sézary syndrome): part II. Prognosis, management, and future directions

Both mycosis fungoides (MF) and Sézary syndrome (SS) have a chronic, relapsing course, with patients frequently undergoing multiple, consecutive therapies. Treatment is aimed at the clearance of skin disease, the minimization of recurrence, the prevention of disease progression, and the preservation of quality of life. Other important considerations are symptom severity, including pruritus and patient age/comorbidities. In general, for limited patch and plaque disease, patients have excellent prognosis on ≥1 topical formulations, including topical corticosteroids and nitrogen mustard, with widespread patch/plaque disease often requiring phototherapy. In refractory early stage MF, transformed MF, and folliculotropic MF, a combination of skin-directed therapy plus low-dose immunomodulators (eg, interferon or bexarotene) may be effective. Patients with advanced and erythrodermic MF/SS can have profound immunosuppression, with treatments targeting tumor cells aimed for immune reconstitution. Biologic agents or targeted therapies either alone or in combination--including immunomodulators and histone-deacetylase inhibitors--are tried first, with more immunosuppressive therapies, such as alemtuzumab or chemotherapy, being generally reserved for refractory or rapidly progressive disease or extensive lymph node and metastatic involvement. Recently, an increased understanding of the pathogenesis of MF and SS with identification of important molecular markers has led to the development of new targeted therapies that are currently being explored in clinical trials in advanced MF and SS.

Cutaneous T-Cell Lymphoma: A Paradigm for Biological Therapies

Mycosis Fungoides and Sézary Syndrome are the most common types of cutaneous T-cell lymphomas. There is no current standard of care for Mycosis Fungoides/Sézary Syndrome, with a general tendency to rely on topical interventions for early disease delaying systemic, more toxic therapy until the development of extensive symptoms. Knowledge of the biological characteristics of this disease has allowed for the development of rational interventions and a significant advance in its treatment. Retinoids are active in Mycosis Fungoides/Sézary Syndrome with the newer rexinoids being available in topical and systemic forms. Interferon alpha remains one of the most active therapeutic agents for Mycosis Fungoides/Sézary Syndrome, especially in combination with other agents such as PUVA. The monoclonal antibody alemtuzumab leads to responses in at least half of patients with advanced disease with its side effect profile consisting mainly of immunosupression and infusion reactions. The recombinant IL2-diphteria toxin denileukin diftitox (Ontak) is active in this disease and appears to have a beneficial effect in symptoms relief and quality of life. Extracorporeal photochemotherapy as an immunostimulating intervention seems to be very effective in a subset of patients, but its availability is limited to less than a hundred centers worldwide. Experimental and less studied interventions include autologous and allogeneic peripheral stem cell transplantation, Interleukin-12, the histone-deacetylator depsipeptide and the synthetic deoxynucleotide CpG7909. Cutaneous T-cell lymphoma has served as a paradigm for the development of biological agents. Further knowledge of the signaling pathways in Mycosis Fungoides/Sézary Syndrome will allow for the development of more effective treatment strategies.

Evidence-based practice of photopheresis 1987-2001: a report of a workshop of the British Photodermatology Group and the U.K. Skin Lymphoma Group

Photopheresis or extracorporeal photochemotherapy (ECP) is a novel immunomodulatory therapy which involves separation of the patient's leucocyte-rich plasma, followed by ex vivo administration of a photosensitizer and ultraviolet A radiation, before reinfusion. ECP has been used successfully for the treatment of cutaneous T-cell lymphoma (CTCL: Sézary syndrome), graft-versus-host disease (GVHD) and cardiac transplant rejection. ECP has a dose-sparing effect on concurrent immunosuppressive therapy. The procedure induces apoptosis of the irradiated lymphocytes, but the exact mechanism by which ECP exerts its therapeutic effect in these different conditions is uncertain. The treatment has very few adverse effects and in particular is not associated with an increased incidence of opportunistic infections. The evidence for the efficacy of ECP has been appraised by a combined British Photodermatology Group and U.K. Skin Lymphoma Group workshop on the basis of evidence published up to the end of 2001 and on the consensus of best practice. There is fair evidence for the use of ECP in erythrodermic CTCL and steroid-refractory GVHD, but randomized controlled studies are needed. There is good evidence supporting the use of ECP in preventing cardiac rejection following transplantation. Randomized controlled trials have also shown a therapeutic benefit in type 1 diabetes mellitus, but the inconvenience associated with the procedure outweighed the clinical benefit. There is fair evidence not to use ECP for the treatment of systemic sclerosis and multiple sclerosis, and good evidence not to use ECP for other forms of CTCL.

Selective immmunotherapy through extracorporeal photochemotherapy: yesterday, today, and tomorrow

ECP's extensive clinical record, as well as a considerable improvement in the understanding of the mechanism that underlies its efficacy, opens potential novel strategies for the treatment of cancer, GVHD, transplant rejection, and autoimmunity. The low side effect profile of this therapy has made it a more attractive treatment consideration than current conventional chemotherapeutic and immunosuppressive medications. As the mechanism of action of ECP is more fully elucidated and clinical studies are completed, the role of ECP in modern therapeutics of CTCL and other malignancies, as well as in the treatment of other T-cell mediated diseases, will be become clearer.

Extracorporeal photochemoimmunotherapy in cutaneous T-cell lymphoma

Extracorporeal photochemotherapy was originally conceived for the treatment of cutaneous T-cell lymphoma (CTCL) and as well as other T-cell mediated diseases. Evidence collected in the past 17 years has demonstrated that this treatment modality can have a very significant effect on the course of a subset of CTCL patients. The evidence available is positive but for a variety of reasons has been controversial within the medical community. A number of very well-designed multi-center trials which have been lacking since the first publication by Edelson et al. are being carried out so that hopefully a number of open questions will be resolved with greater clarity in the coming years. The fact remains that this innovative approach for the treatment of CTCL and T-cell mediated diseases has certainly opened new avenues of therapy and thought in photoimmunology and photomedicine. Clearly the very low side effect profile of this therapy has made it more attractive than the chemotherapeutic and immunosuppressive substances that are presently available or in experimental protocols. If and when the mechanisms of action are fully understood and appropriate studies investigating different treatment schedules and different combination therapies and modifications of its present form are performed the place of photopheresis in the therapeutics of CTCL as well as other T-cell mediated diseases and oncology will be better placed.

Extracorporeal photochemoimmunotherapy in cutaneous T cell lymphomas

Extracorporeal photochemotherapy (ECP), or photopheresis, is a widely used treatment for cutaneous T cell lymphoma (CTCL) and other T cell-mediated disorders, having been administered in more than 150 centers worldwide more than 200,000 times. Consistent with the theme of this conference--that is, highlighting the potentially most productive investigative avenues for unraveling the mysteries of CTCL in the next decade--ECP has been futuristic since its inception in the early 1980s. In 1988, the treatment was the first FDA-approved selective immunotherapy for any type of cancer. Yet, the mechanism by which it could suppress a clone of CTCL cells or inactivate multiple autoreactive T cell clones in graft-versus-host disease (GVHD) or allograft rejection remained obscure until quite recently. In fact, the scientific principles necessary to begin to comprehend the basis of ECP's efficacy were not available when the treatment was first introduced in 1982. In the intervening years, necessary detailed knowledge of the structure and function of the clonotypic T cell receptors, of class I major histocompatibility complex (MHC) presentation of tumor antigens, of CTCL tumor-specific antigens, of dendritic antigen presenting cell (DC) biology, and of 8-methoxypsoralen immunopharmacology has been attained. Although much remains to be learned, we now appreciate that ECP simultaneously and efficiently induces both apoptosis of disease-causing T cells and conversion of monocytes to functional DCs. By processing and presenting the unique antigenic determinants of pathogenic T cell clones, the DCs can either initiate a clinically relevant anti-CTCL cytotoxic response or suppress the activity of autoreactive T cell clones. This paper will review clinical trials of ECP in CTCL and evolving scientific understanding of ECP's mechanism in the context of exciting future directions.