Phase II study of pentostatin and intermittent high-dose recombinant interferon alfa-2a in advanced mycosis fungoides/Sézary syndrome

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.

STING Signaling and Skin Cancers

Recent developments in immunotherapy against malignancies overcome the disadvantages of traditional systemic treatments; however, this immune checkpoint treatment is not perfect and cannot obtain a satisfactory clinical outcome in all cases. Therefore, an additional therapeutic option for malignancy is needed in oncology. Stimulator of interferon genes (STING) has recently been highlighted as a strong type I interferon driver and shows anti-tumor immunity against various malignancies. STING-targeted anti-tumor immunotherapy is expected to enhance the anti-tumor effects and clinical outcomes of immunotherapy against malignancies. In this review, we focus on recent advancements in the knowledge gained from research on STING signaling in skin cancers. In addition to the limitations of STING-targeted immunotherapy, we also discuss the clinical application of STING agonists in the treatment of skin cancer.

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.

How we treat advanced stage cutaneous T-cell lymphoma - mycosis fungoides and Sézary syndrome

T-cell lymphomas (TCLs) constitute a rare subset of non-Hodgkin lymphomas, with mycosis fungoides/Sézary syndrome (MF/SS) being the most common subtype of cutaneous TCLs (CTCLs). Considered an incurable but treatable disease, MF/SS management presents several challenges including diagnostic delays, debilitating effect on patients' quality of life, need for several lines of therapies, multidisciplinary care and cumulative drug toxicities limiting duration of use. The present review intends to provide an overview of the recent advances in our understanding of the biology of CTCL and how these are being leveraged to provide additional treatment options for management of advanced and recurrent disease. In addition, the discussion of the different modalities of treatment is summarised to further outline the importance of multidisciplinary care and early referral to CTCL centres.

Management of primary cutaneous lymphomas during the COVID-19 pandemic

Primary cutaneous lymphomas are defined as a heterogenic group of T- and B-cell non-Hodgkin lymphomas that present initially in the skin. Patients with primary cutaneous lymphomas are at a higher risk for developing complications in case of infection with the novel coronavirus severe acute respiratory syndrome coronavirus 2. The coronavirus disease 2019 (COVID-19) pandemic has affected the established diagnostic approach, staging, and therapeutic guidelines in patients with primary cutaneous lymphomas. In the light of the current global health crisis, management of primary cutaneous lymphomas needs to be adjusted. The key to achieving this is to balance the optimal control of the lymphoma, with a minimal increase of the personal risk for COVID-19 exposure and complications.

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.

Cutaneous T-cell lymphomas: Focusing on novel agents in relapsed and refractory disease

Patients with relapsed or refractory cutaneous T-cell lymphoma (CTCL) display a dismal prognosis and their therapy represents an unmet medical need, as the best treatment strategy is yet to be determined. Exciting data on novel targeted agents are now emerging from recently concluded and ongoing clinical trials in patients with relapsed and refractory CTCL. Three FDA approved compounds are used as single agents including the oral retinoid bexarotene and histone deacetylase inhibitors romidepsin and vorinostat. Brentuximab vedotin, an anti-CD30 drug-conjugated monoclonal antibody, has received from European Commission the orphan designation but has not been approved by EMA yet. Several other molecules have demonstrated their activity in the same context and combination strategies are being explored. Participation in a well designed clinical trial is encouraged, as the introduction of novel agents will continue to expand the therapeutics options available in the management of CTCL.

Cutaneous T-cell lymphoma: 2017 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders 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 biologic-response modifiers or histone deacetylase inhibitors prior to escalating therapy to include systemic, single-agent chemotherapy. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

Purine nucleoside analogues: fludarabine, pentostatin, and cladribine

Purpose. The primary objective of this article is to continue the discussion of the pharmacology, phar macokinetics, clinical use, and adverse effects of the currently approved adenosine analogues, focusing on pentostatin. This is part two of a three part series.

Data Sources. We reviewed the literature through a MEDLINE search from 1986 to 1996. Rele vant articles cited in the literature obtained by MED LINE searching also were considered. We searched the following terms: fludarabine, cladribine, pentosta tin, apoptosis, and adenosine analogues. The search was restricted to the English language.

Data Extraction. We have reviewed the current literature in regard to the chemistry, mechanisms of action and pharmacology, pharmacokinetics, clinical use, adverse effects, drug interactions, indications, formulation, dosage, administration, and pharmaceu tical issues of the currently approved adenosoine analogues, focusing on pentostatin.

Data Synthesis. The adenosine analogues are structurally similar agents used in the management of hematological malignancies. Pentostatin and cladrib ine are both active agents in the treatment of hairy cell leukemia. There are no comparative clinical trials between the agents, and we have provided compari sons based on pharmacology, clinical experience, adverse effects, and cost.

How I treat mycosis fungoides and Sézary syndrome

Mycosis fungoides (MF) is the most common primary cutaneous T-cell lymphoma variant and is closely related to a rare leukemic variant, Sézary syndrome (SS). MF patients at risk of disease progression can now be identified and an international consortium has been established to address the prognostic relevance of specific biologic factors and define a prognostic index. There are a lack of randomized clinical trial data in MF/SS and evidence is based on a traditional “stage-based” approach; treatment of early-stage disease (IA-IIA) involves skin directed therapies which include topical corticosteroids, phototherapy (psoralen with UVA or UVB), topical chemotherapy, topical bexarotene, and radiotherapy including total skin electron beam therapy. Systemic approaches are used for refractory early-stage and advanced-stage disease (IIB-IV) and include bexarotene, interferon α, extracorporeal photopheresis, histone deacetylase inhibitors, and antibody therapies such as alemtuzumab, systemic chemotherapy, and allogeneic transplantation. However, despite the number of biologic agents available, the treatment of advanced-stage disease still represents an unmet medical need with short duration of responses. Encouragingly, randomized phase 3 trials are assessing novel agents, including brentuximab vedotin and the anti-CCR4 antibody, mogamulizumab. A broader understanding of the biology of MF/SS will hopefully identify more effective targeted therapies.

Cutaneous T-cell lymphoma: 2016 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders 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 blood involvement are generally approached with biologic-response modifiers or histone deacetylase inhibitors before escalating therapy to include systemic, single-agent chemotherapy. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

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.

Cutaneous T-cell lymphoma: 2014 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders 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, and 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 blood involvement are generally approached with biologic-response modifiers or histone deacetylase inhibitors prior to escalating therapy to include systemic, single-agent chemotherapy. Multiagent chemotherapy (e.g., CHOP) may be employed for those patients with extensive visceral involvement requiring rapid disease control. In highly selected patients, allogeneic stem-cell transplantation may be considered.

Cutaneous T-cell lymphomas: a review of new discoveries and treatments

Treatment regimens of patients with CTCL vary widely based on clinician preference and patient tolerance. Skin directed therapies are recommended for patients with early stage IA and IB MF, with combinations used in refractory cases. While no regimen has been proven to prolong survival in advanced stages, immunomodulatory regimens should be used initially to reduce the need for cytotoxic therapies. In more advanced stages of disease, treatment efforts should strive for palliation and improvement of quality of life. With many new therapies and strategies on the horizon, the future looks promising for CTCL patients. Unfortunately, other than allogeneic HCT, there are no potential curative therapies for CTCL. Clinical trials are currently underway to identify new therapies to improve quality of life for patients, and researchers are hard at work to identify novel pathways and genes for prognostication and as targets for therapies. Importantly, collaborative clinical trials to enhance rates of accrual need to be conducted, and improved interpretation of data via standardizing end points and response criteria should be an emphasis. Recently, the International Society for Cutaneous Lymphomas (ISCL), the United States Cutaneous Lymphoma Consortium (USCLC), and the Cutaneous Lymphoma Task Force of the European Organisation for Research and Treatment of Cancer (EORTC) met to develop consensus guidelines to facilitate collaboration on clinical trials. These proposed guidelines consist of: recommendations for standardizing general protocol design; a scoring system for assessing tumor burden in skin, lymph nodes, blood, and viscera; definition of response in skin, nodes, blood, and viscera; a composite global response score; and a definition of end points. Although these guidelines were generated by consensus panels, they have not been prospectively or retrospectively validated through analysis of large patient cohorts.

Allogeneic stem cell transplantation versus conventional therapy for advanced primary cutaneous T-cell lymphoma

BACKGROUND

Primary cutaneous T-cell lymphomas (CTCL) belong to the group of non-Hodgkin lymphomas and usually run an indolent course. However, some patients progress to advanced tumour or leukaemic stages. Up to now, no curative treatment has been established for those cases. In the last few years, several publications have reported durable responses in some patients following allogeneic stem cell transplantation (alloSCT).

OBJECTIVES

To compare the efficacy and safety of conventional therapies with allogeneic stem cell transplantation in patients with advanced primary cutaneous T-cell lymphomas.

SEARCH METHODS

The search strategy included the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1950 to May 2011), Internet-databases of ongoing trials (www.controlled-trials.com; www.clinicaltrials.gov), conference proceedings of the American Society of Clinical Oncology (ASCO, 2009 to present) and the American Society of Hematology (ASH, 2009 to present). We also contacted members of the European Organisation for Research and Treatment of Cancer (EORTC) Cutaneous Lymphoma Task Force to check for ongoing study activities. We handsearched citations from identified trials and relevant review articles. In addition, randomised controlled trials from the European Group for Blood and Marrow Transplantation (EBMT) and International Conference on Cutaneous T-cell Lymphoma, ASCO and ASH up to 2010 were handsearched.

SELECTION CRITERIA

Genetically randomised controlled trials (RCT) comparing alloSCT plus conditioning therapy regardless of agents with conventional therapy as treatment for advanced CTCL were eligible to be included.

DATA COLLECTION AND ANALYSIS

From eligible studies data would have been extracted by two review authors and assessed for quality. Primary outcome measures were overall survival, secondary criteria were time to progression, response rate, treatment-related mortality, adverse events and quality of life.

MAIN RESULTS

We found 2077 citations but none were relevant genetically or non-genetically randomised controlled trials. All 41 studies that were thought to be potentially suitable were excluded after full text screening for being non-randomised, not including CTCL or being review articles.

AUTHORS' CONCLUSIONS

We planned to report evidence from genetically or non-genetically randomised controlled trials comparing conventional therapy and allogeneic stem cell transplantation. However, no randomised trials addressing this question were identified. Nevertheless, prospective genetically randomised controlled trials need to be initiated to evaluate the precise role of alloSCT in advanced CTCL.

Cutaneous T-cell lymphoma: 2011 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders 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

Tumor, node, metastasis, and blood (TNMB) 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 blood involvement are generally approached with biologic-response modifiers, denileukin diftitox, and histone deacetylase inhibitors before escalating therapy to include systemic, single-agent chemotherapy. Multiagent chemotherapy may be used for those patients with extensive visceral involvement requiring rapid disease control. In highly-selected patients with disease refractory to standard treatments, allogeneic stem-cell transplantation may be considered.

Current and emerging treatment strategies for cutaneous T-cell lymphoma

Cutaneous T-cell lymphomas (CTCLs) are a rare group of mature T-cell lymphomas presenting primarily in the skin. The most common subtypes of CTCL are mycosis fungoides and its leukaemic variant Sézary's syndrome. Patients with early-stage disease frequently have an indolent clinical course; however, those with advanced stages have a shortened survival. For the treating physician, the question of how to choose a particular therapy in the management of CTCL is important. These diseases span the disciplines of dermatology, medical oncology and radiation oncology. Other than an allogeneic stem cell transplant, there are no curative therapies for this disease. Hence, many treatment modalities need to be offered to the patient over the course of their life. An accepted treatment approach has been to delay traditional chemotherapy, which can cause excessive toxicity without durable benefit. More conservative treatment strategies in the initial management of CTCL have led to the development of newer biological and targeted therapies. These therapies include biological immune enhancers such as interferon alpha and extracorporeal photopheresis that exert their effect by stimulating an immune response to the tumour cells. Retinoids such as bexarotene have been shown to be effective and well tolerated with predictable adverse effects. The fusion toxin denileukin diftitox targets the interleukin-2 receptor expressed on malignant T cells. Histone deacetylase inhibitors such as vorinostat and romidepsin (depsipeptide) may reverse the epigenetic states associated with cancer. Forodesine is a novel inhibitor of purine nucleoside phosphorylase and leads to apoptosis of malignant T cells. Pralatrexate is a novel targeted antifolate that targets the reduced folate carrier in cancer cells. Lastly, systemic chemotherapy including transplantation is used when rapid disease control is needed or if all other biological therapies have failed. As response rates to most of the biological agents used to treat CTCL are 25-30%, it is also reasonable to consider clinical trials with novel agents if one or two front-line therapies have failed, especially before considering chemotherapy. CTCL is largely an incurable disease with significant morbidity and more active agents are needed.

How I treat mycosis fungoides and Sézary syndrome

The most common subtypes of primary cutaneous T-cell lymphomas are mycosis fungoides (MF) and Sézary syndrome (SS). The majority of patients have indolent disease; and given the incurable nature of MF/SS, management should focus on improving symptoms and cosmesis while limiting toxicity. Management of MF/SS should use a “stage-based” approach; treatment of early-stage disease (IA-IIA) typically involves skin directed therapies that include topical corticosteroids, phototherapy (psoralen plus ultraviolet A radiation or ultraviolet B radiation), topical chemotherapy, topical or systemic bexarotene, and radiotherapy. Systemic approaches are used for recalcitrant early-stage disease, advanced-stage disease (IIB-IV), and transformed disease and include retinoids, such as bexarotene, interferon-α, histone deacetylase inhibitors, the fusion toxin denileukin diftitox, systemic chemotherapy including transplantation, and extracorporeal photopheresis. Examples of drugs under active investigation include new histone deacetylase inhibitors, forodesine, monoclonal antibodies, proteasome inhibitors, and immunomodulatory agents, such as lenalidomide. It is appropriate to consider patients for novel agents within clinical trials if they have failed front-line therapy and before chemotherapy is used.

Mycosis fungoides

Mycosis fungoides (MF) constitutes the most frequent cutaneous T-cell lymphoma. Sezary syndrome is considered by some authors to be an erythrodermic leukemic variant of MF, but is classified separately in the new WHO-EORT classification of cutaneous lymphomas. MF usually occurs in old adults with a 2:1 male to female ratio. Its prognosis is variable and strongly conditioned by the extent and type of skin involvement and presence of extracutaneous disease. Patients with stage IA-disease have an excellent prognosis with an overall long-term life expectancy that is similar to an age-, sex-, and race-matched control population. Almost all patients with stage IA MF will die from causes other than MF, with a median survival >33 years. Only 9% of these patients will progress to more extended disease. Patients with stage IB or IIA have a median survival greater than 11 years. These patients with T2 disease have a likelihood of disease progression of 24% and nearly 20% die of MF. Subgroups with stage IB or IIA have similar prognosis. Patients with cutaneous tumors or generalized erythroderma have a median survival of 3 and 4.5 years, respectively. The majority of these patients will die of MF. Extracutaneous dissemination is observed in less than 10% of patients with patch or plaque disease and in 30-40% of patients with tumors or generalized erythrodermatous involvement. Extracutaneous involvement is directly correlated to the extent of cutaneous disease. The most commonly involved organs are lung, spleen, liver, and gastrointestinal tract. Patients with extracutaneous disease at presentation involving either lymph nodes or viscera have a median survival of <1.5 years. Patients with plaque-type or erythrodermic MF may develop cutaneous tumors with large cell histology, often expressing CD30, which share a common clonal origin as observed in their preexisting MF and are associated with a less favourable outcome.

Efficacy and tolerability of currently available therapies for the mycosis fungoides and Sezary syndrome variants of cutaneous T-cell lymphoma

Primary cutaneous T-cell lymphomas are a heterogenous group of non-Hodgkin lymphomas. The characteristic clinicopathologic and immunophenotypic features and prognoses of the various cutaneous lymphomas have been recently described by the World Health Organization and European Organization for Research and Treatment of Cancer. Cutaneous T-cell lymphoma variants include mycosis fungoides and Sezary syndrome, which are generally associated, respectively, with indolent and aggressive clinical courses and are the subject of this review. Currently utilized treatments for cutaneous T-cell lymphoma include skin-directed therapies (topical agents such as corticosteroids, mechlorethamine, carmustine, and retinoids, phototherapy, superficial radiotherapy, and total skin electron beam therapy), systemic therapies (photophoresis, retinoids, denileukin diftitox, interferons, and chemotherapy), and stem cell transplantation (autologous and allogeneic). This review will describe recent advances in our understanding of the biology (immunologic, cytogenetic, and genetic) of cutaneous T-cell lymphomas and discuss the efficacy and tolerability of the current therapeutic options for cutaneous T-cell lymphomas. Disease progression in over 20% of patients with early stages of disease and the current lack of a definitive treatment which produces durable responses in advanced stages of disease indicates a critical unmet need in CTCL. New insights into the molecular and immunologic changes associated with cutaneous T-cell lymphomas should ultimately lead to the identification of novel therapeutic targets and the development of improved therapeutic options for patients with these malignancies.

Purine Analogues in Advanced T-Cell Lymphoid Malignancies

T-cell lymphomas account for 10% to 15% of all lymphoid malignancies. In advanced stages of T-cell lymphoma, single or multiagent chemotherapy and bioimmunotherapeutic agents have been used. Purine analogues have demonstrated activity in both refractory cutaneous T-cell lymphoma and peripheral T-cell lymphoma with response rates ranging from 20% to 70%. Response rates have been higher with pentostatin (60%) than with the other compounds in this class. The potential limitation to this therapy is the prolonged immunosuppression, which increases the risk of opportunistic injections in patients who are already at heightened risk for infections. Patients should be monitored closely with CD4 counts and surveillance for opportunistic infections. Future studies of purine analogues should evaluate patients who are less heavily pretreated and combination therapy with other agents such as alemtuzumab should be investigated in order to prolong the duration of disease remission.

Pentostatin and purine analogs for indolent lymphoid malignancies

Pentostatin has been shown to be active in a variety of B- and T-cell malignancies. The drug is a tight inhibitor of adenosine deaminase, a key degradative enzyme of purine metabolism present in all human tissues, with the highest levels found in the lymphoid system. Early clinical trials indicated that this agent was highly active in acute lymphoblastic leukemias with high intracellular adenosine deaminase levels. Relatively high doses of the drug were needed, which was associated with severe adverse events. Through the efforts of a few investigators, better tolerated, low-dose regimens have been shown to be extremely active in lymphoproliferative diseases with very low intracellular adenosine deaminase levels such as hairy cell leukemia, B- and T-cell chronic leukemias, T-cell cutaneous lymphomas and low-grade non-Hodgkin lymphomas. Clinical as well as experimental data have indicated that this drug induces lymphocyte-specific cytotoxicity, and myelosuppressive adverse events have been minimal. Although all the purine analogs have shown similar activity, the advantage of pentostatin is the relatively specific cytotoxicity against lymphocytes, which permits treatment even in patients with severe cytopenias. Although no direct comparisons of the purine analogs have been performed, pentostatin may be preferred due to this property.

Durable Clinical, Cytogenetic, and Molecular Remissions After Allogeneic Hematopoietic Cell Transplantation for Refractory Sezary Syndrome and Mycosis Fungoides

Purpose

Sezary syndrome (SS) and tumor-stage mycosis fungoides (MF) are generally incurable with currently available treatments. We conducted a retrospective study to evaluate the outcome of allogeneic hematopoietic stem-cell transplantation (HSCT) in this patient population.

Patient and Methods

From August 1996 through October 2002, eight patients with advanced MF/SS underwent allogeneic HSCT at our institution. All patients were heavily pretreated, having failed a median number of seven prior therapies (range, five to 12). Clonal T-cell populations in peripheral blood or bone marrow were detectable by polymerase chain reaction analyses of T-cell receptor γ-chain gene rearrangements in six patients and cytogenetics in three patients. The conditioning regimen included total-body irradiation and cyclophosphamide (n = 3), busulfan and cyclophosphamide (n = 1), and the reduced-intensity regimen of fludarabine and melphalan (n = 4). Allogeneic hematopoietic stem cells were obtained from HLA-matched siblings (n = 4) and unrelated donors (n = 4).

Results

All patients achieved complete clinical remission and resolution of molecular and cytogenetic markers of disease within 30 to 60 days after HSCT. Two patients died from transplantation-related complications; graft-versus-host disease (GVHD; n = 1) and respiratory syncytial virus pneumonia (n = 1). With a median follow-up of 56 months, six patients remain alive and without evidence of lymphoma.

Conclusion

Our results suggest that allogeneic HSCT from both HLA–matched sibling and unrelated donors can induce durable clinical, molecular, and cytogenetic remissions in patients with advanced cutaneous T-cell lymphoma that is refractory to standard therapies.

What's new in the management of cutaneous T-cell lymphoma?

The aetiology and clinical management of primary cutaneous T-cell lymphoma (CTCL) and specifically of mycosis fungoides and Sezary syndrome are poorly defined. Interesting new insights into CTCL disease biology as well as a number of emerging of novel therapeutic interventions make this an increasingly interesting area for dermatologists and oncologists involved in the treatment of CTCL. This review article covers much of this new information including new drugs, such as denileukin diftitox (Ontak) a targeted cytotoxic biological agent, Bexarotene an RXR selective retinoid, anti-CD4 monoclonal antibodies (mAb), new cytotoxics agents and vaccines.

Pilot study of etanercept in patients with relapsed cutaneous T-cell lymphomas

BACKGROUND

Tumor necrosis factor (TNF)-alpha has been implicated in the pathogenesis of cutaneous T-cell lymphoma (CTCL).

OBJECTIVE

To assess the toxicity, safety, and efficacy of etanercept (soluble TNF receptor) in patients with relapsed CTCL.

METHODS

Etanercept was administered twice weekly at a dose of 25 mg subcutaneously. Patients with improvement after two months could be continued on treatment.

RESULTS

Twelve out of the 13 patients enrolled on study were evaluable (Stage I-IIA, 3 patients; Stage IIB-IV disease, 9 patients). The median number of previous therapies was 7 (range, 3-12). Etanercept induced partial remission in one patient (8%) and minor response in one patient (8%), both of whom had Stage IB disease. Most patients experienced no side effects.

CONCLUSION

This pilot study suggests that etanercept is safe and generally well tolerated in patients with CTCL. The effect of etanercept in a larger cohort of patients with early disease merits investigation.

Interferon in the treatment of cutaneous T-cell lymphoma

Interferons are polypeptides with a broad range of in vivo effects that have shown efficacy in cutaneous T-cell lymphoma (CTCL). Particularly useful is alfa interferon (IFN) which, as a single agent, has shown partial remission rates of > 50% and complete responses of > 20%. Side-effects are predictable, generally well tolerated and dose-related. The efficacy of IFN has increased with combination therapy without any significant increase in attendant side-effects. An update on the specifics of the different IFN subtypes, their inherent biologic activity, pharmacokinetics, efficacy and safety in CTCL is presented in this paper.

Phase II study of pentostatin in advanced T-cell lymphoid malignancies

BACKGROUND

The goal of the current study was to assess the toxicity, safety, and efficacy of pentostatin in patients with T-cell lymphoid malignancies.

METHODS

Patients were eligible if they had biopsy-proven T-cell lymphoma or leukemia and failure to respond to previous therapy or an expected complete response rate to conventional therapy of < 20%. Pentostatin was administered at an initial dose of 3.75 or 5.0 mg/m(2) by intravenous bolus daily over a consecutive 3-day period every 3 weeks.

RESULTS

Forty-two of 44 patients enrolled in the study were evaluable. The median age of the patients was 62 years (range, 38-86 years). Patients received a median of 3 previous therapies (range, 0-10 previous therapies). Of these patients, 32 (76%) had mycosis fungoides/Sézary syndrome and 10 patients (24%) had other T-cell leukemias or lymphomas. The overall response rate was 54.8% (complete remission, 6 patients [14.3%]; partial remission, 17 patients [40.5%]). Durable responses were observed mainly in patients with Sézary syndrome or peripheral T-cell lymphoma. The median follow-up period for surviving patients was 20 months (range, 1-83+ months). The median duration of response was 4.3 months (range, 1-61 months). The most common toxicities were neutropenia, nausea, and CD4 suppression. A transient early "flare" of disease was observed in some responders.

CONCLUSIONS

At these doses, pentostatin was reasonably well tolerated and is an effective drug for the treatment of T-cell lymphomas.

Cytokine therapy of cutaneous T-cell lymphoma: interferons, interleukin-12, and interleukin-2

It is well accepted that cutaneous T-cell lymphomas (CTCL), including mycosis fungoides and Sézary syndrome, represent lymphomas that are highly responsive to immune modifying agents. Furthermore, the recent emphasis on the use of cytokine-related therapeutics is based upon the exceedingly important role of the host immune response in effecting progression of disease. In this article we discuss the data that support the importance of the host immune response in the control of progression of CTCL and the role that cytokine therapy has in supporting the host immune response and the effects of this approach to induce regression of skin and systemic disease.

Peripheral T- cell lymphomas: diagnosis and management

Peripheral T-cell lymphomas are a diverse group of diseases with varying clinical manifestations. Response to conventional chemotherapy generally is poor. Treatment using purine analogs has achieved response rates between 25% and 60% in relapsed/refractory patients, with minimal toxicity. The highest response rates were seen with pentostatin and gemcitabine. Using purine analogs in combination therapy may improve response rates, albeit with an increased risk of toxicity. The role of purine analogs as first line therapy in patients who have otherwise favorable prognostic factors has not been defined. Monoclonal antibody therapy has emerged in the last decade as a promising approach in treating T-cell malignancies. Campath-1H is an effective and well-tolerated therapy in these diseases. Durable remissions have been seen in heavily pretreated patients and in up to two thirds of patients who had T-PLL, which is the largest disease group studied. These results in T-PLL are significantly better than those reported with other therapies; this suggests that Campath-1H should be moved to first line therapy in this aggressive disease. The way in which monoclonal antibodies work indicate that they may be particularly useful in treating patients who have minimal residual disease, and, in this setting, facilitate stem cell transplantation. In addition, the activity of Campath-1H to deplete T cells has been exploited in preparative regimens before allogeneic bone marrow transplantation. These approaches may be worth further investigation in patients who have T-cell lymphomas. None of the therapies that are available to treat the mature T-cell neoplasms seems to be curative, other than in selected patients who have favorable ALCL. Much of the data have been drawn from small, non-randomized studies. There is a need for larger, prospective, randomized trials to examine these novel therapies and to further explore combination regimens, which may exploit potential synergism.

Lymphoma of the skin

This chapter describes the various ways in which the non-Hodgkin's lymphomas can involve the skin, how these diseases should be assessed, standard treatments available in 2002, and new directions in research. The goal of the session is to succinctly review recent developments in lymphoma classification and treatment as they apply to the unique aspects of lymphoma when manifest in the skin. In Section I, Dr. Eric Hsi reviews the special characteristics of the lymphomas seen when they proliferate in the skin and the application of the new World Health Organization classification system to the cutaneous lymphomas, emphasizing the unique challenges of recognizing and correctly classifying these diseases. He summarizes the evidence in favor of including the skin lymphomas in the overall lymphoma classification scheme and concludes with a practical description of the specific skin lymphoma entities. In Section II, Dr. Joseph Connors describes the current optimal treatment of the B-cell lymphomas when they present in or metastasize to the skin. Building on the classification scheme described by Dr. Hsi, Dr. Connors outlines a treatment approach based on current understanding of pathophysiology of these diseases and application of each of the effective modalities available for cutaneous lymphoma including radiation, chemotherapy, and immunotherapy. In Section III, Dr. Francine Foss concludes the session with a discussion of the different T-cell lymphomas that start in or spread to the skin concentrating on mycosis fungoides, cutaneous anaplastic large cell lymphoma and peripheral T-cell lymphoma. She includes comments on the newer anti-T-cell chemo- and immuno-therapeutics focusing on agents and techniques specific for cutaneous T-cell lymphomas.

Non-Hodgkin's lymphoma: the evolving role of purine analogues

Indolent non-Hodgkin's lymphoma is the commonest form of lymphoma in the USA and Europe, with a long natural history with multiple responses and relapses. Indolent lymphomas include follicular lymphomas (the more frequent subtype), immunocytoma, and small lymphocytic lymphomas according to the Revised European-American Lymphoma classification. The tendency has been to use simple oral medication until patients have more advanced aggressive disease but new agents such as the purine analogues have led to re-evaluation of this approach. The newer purine analogues -- fludarabine, 2-chlorodeoxyadenosine (cladribine) and deoxycoformycin (pentostatin) -- are a group of potently lymphotoxic antimetabolite molecules. Their activity in the indolent non-Hodgkin's lymphomas, in particular in the follicular subtype, may be due to their unique ability as antimetabolites to inhibit resting as well as dividing cells. Within the last decade they have moved from salvage therapy to front-line studies. Further insight into the mechanism of action of the purine analogues will to lead to further advances in this group of diseases.

Treatment of cutaneous T cell lymphoma: current status and future directions

The treatment of cutaneous T cell lymphoma (CTCL), which includes mycosis fungoides and Sezary syndrome, has been in a state of continual change over recent decades, as new therapies are constantly emerging in the search for more effective treatments for the disease. However, prognosis and survival of patients with CTCL remains dependent upon overall clinical stage (stage IA-IVB) at presentation, as well as response to therapy. Past therapies have been limited by toxicity or the lack of consistently durable responses, and few treatments have been shown to actually alter survival, especially in the late stages of disease. Even aggressive chemotherapy has not been shown to improve overall survival compared to conservative sequential therapy in advanced disease, and adds the risk of immunosuppressive complications. Over the last decade, extracorporeal photopheresis has been the only single treatment that has been shown to improve survival in patients with Sezary syndrome, although its true efficacy and place in combination therapy remain unclear. Much of the focus of current research has been on combinations of skin-directed therapies and biological response modifiers, which improve response rates. The results of various trials over the years have also brought into favor the use of post-remission maintenance therapy with topical corticosteroids, topical mechlorethamine (nitrogen mustard), interferon-alpha, or phototherapy to prevent disease relapse. Recent novel developments in CTCL therapy include oral bexarotene, a retinoid X receptor-selective retinoid that has activity in all stages of CTCL, and the topical gel formulation of bexarotene, which plays a role in treating localized lesions. US Food and Drug Administration (FDA)-approved, oral systemic bexarotene has the advantage of a 48% overall response rate at a dosage of 300 mg/m(2)/day, and avoids immunosuppression and risk of central line and catheter-related infectious complications that are associated with other systemic therapies. Monitoring of triglycerides and use of concomitant lipid-lowering agents and thyroid replacement is required in most patients. Also recently FDA-approved, denileukin diftitox is the first of a novel class of fusion toxin proteins and is selective for interleukin-2R (CD25+) T cells, targeting the malignant T cell clones in CTCL. Denileukin diftitox is associated with capillary leak syndrome in 20 to 30% of patients, which may be ameliorated by hydration and corticosteroids. Higher response rates are possible by combining bexarotene with "statin" drugs and active CTCL therapies. Studies are being conducted on combining bexarotene and denileukin diftitox with other modalities. Biological response modifier therapies that are in current or future investigational trials include topical tazarotene, pegylated interferon, interleukin-2, and interleukin-12. At the forefront of systemic chemotherapy development, pegylated liposomal doxorubicin, gemcitabine, and pentostatin appear to have the greatest potential for success in CTCL therapy. Bone marrow transplantation, which is currently limited by the risk of graft-versus-host disease, offers the greatest potential for disease cure. Further developments for CTCL may include more selective immunomodulatory agents, vaccines, and monoclonal antibodies.

Cutaneous T-cell lymphoma. New immunomodulators

During the most recent decades, much knowledge has been gained concerning the immunologic and pathologic mechanisms of CTCL. The development of immunomodulators aimed at correcting aberrations in immunology and cellular growth and differentiation reflects this increased understanding. This review of the currently available immune-response modifying drugs shows that recombinant forms of natural cytokines and retinoids can be developed with tolerable toxicity profiles and substantial efficacy. Although milestone drugs such as bexarotene have been approved by the FDA- for treatment of CTCL, other agents such as IL-12 may also have a place in treatment of the disease. Even though unapproved, IFN-alpha may be the most active single immunomodulating agent against CTCL. It seems that further delineation of CTCL cytokine profile changes and immunologic aberrations are key in developing effective immunomodulators that are able to reverse these alterations.

Interferons: potential roles in affect

A review of the literature on interferons was conducted and possible roles in neuropsychiatric disorders with affective disturbances are assessed. Interferons and interferon receptors are present in the limbic system where they appear to exert physiological effects pertinent to affect, most potently when levels rise during CNS infections. Interferons interact closely with cytokines and nitric oxide, signaling molecules implicated in depression. Results from knock-out mice suggest a role for interferon-gamma in moderating fear and anxiety, while other lines of evidence point to a role in arousal and circadian rhythms. The interferon-alpha receptor deploys an arginine methyltransferase affecting RNA editing and splicing, which seem to be disrupted in schizophrenia and bipolar disorder. S-Adenosylmethionine (SAMe), an effective antidepressant, may owe its effects in the latter disorders in part to variations in the strength of interferon-alpha signaling impacting RNA processing. Antiviral effects of interferons are of interest in lieu of viral theories of affective disorders. Finally, the relative levels of interferons gamma and alpha might play important roles in neural, and glial, development, as well as the dialog between the CNS and the immune system.

An oncologist's approach to therapy for cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma (CTCL) includes a heterogeneous group of diseases manifested in many cases by a prolonged clinical course. Even patients with advanced clinical disease, including erythroderma, adenopathy, and cutaneous tumors, can respond to a number of conservative therapeutic modalities, including radiation, cutaneous and extracorporeal phototherapy, and interferon. More aggressive systemic therapies are generally reserved for patients with visceral involvement or effaced (LN4) lymph node disease or patients refractory to multiple conservative approaches. Since no survival benefit has been demonstrated for multiagent cytotoxic chemotherapy regimens, this therapy is generally reserved for patients whose disease demonstrates an aggressive clinical course requiring immediate palliation. Durable responses (5+ years) have been reported with purine analogues; however, prolonged immunosuppression and increased frequency of opportunistic infections have been demonstrated. Novel therapeutic agents, including interleukin-2, interleukin-12, the phosphorylase inhibitor peldesine (BCX-34), and bexarotene, have demonstrated activity. The interleukin-2 diphtheria toxin fusion protein, DAB(389)IL-2, has demonstrated a 30% response rate in advanced and refractory CTCL patients. The optimal role of targeted biological therapies in advanced patients will likely be in the minimal disease setting following either chemotherapy or radiation.

Emerging new therapies for cutaneous T-cell lymphoma

Improved therapy for CTCL will depend on a better understanding of the pathogenesis of this disease at a molecular level. It is clear that the T cells in MF and CTCL do not undergo normal programmed cell death and have prolonged lifespans. Skin flora or other antigens may stimulate the initial proliferation, offering another approach to change the course of the disease. There has been tremendous interest in biological response modifiers, and the first targeted fusion toxin to activated T cells has been approved for CTCL. New retinoids with increased selectivity and decreased side effects are being tested for this disease. In summary, the treatment of CTCL should continue to improve and should be focused on strategies that preserve the immune function in these patients.

Radiotherapy of advanced mycosis fungoides: indications and results of total skin electron beam and photon beam irradiation

BACKGROUND

The goals of this retrospective study of advanced mycosis fungoides are (1) to describe the indications of a combination of total skin electron beam and photon beam irradiation and (2) to analyze the results of total body or segmental photon irradiation for patients with extension beyond the skin.

METHODS

From January 1975 to December 1995, 45 patients with pathologically-confirmed mycosis fungoides or Sézary syndrome received a combination of TSEB and photon beam irradiation for advanced disease: 34 males and 11 females, mean age 61 years (range 27-87 years). The mean follow-up was 111 months (range 18-244 months, median 85 months). Whole-skin irradiation treatment to a depth of 3-5 mm with a 6-MeV electron beam was produced by a linear accelerator to a total dose of 24-30 Gy in 8-15 fractions, 3-4 times a week. In cases of thick plaques or tumors that were beyond the scope of low energy electron beams or for treating nodal areas (especially in the head and neck area or axilla involvement), regional irradiation (RRT) with Co-60 photon beams was followed by whole-skin electron beam irradiation (15 patients). In cases of diffuse erythrodermia, Sézary syndrome, nodal or visceral involvement, total body irradiation was delivered with a 25-MV photon beam using a split-course regimen to prevent hematological toxicity (22 patients). The first course consisted of 1.25 Gy delivered in ten fractions and 10 days. Subsequently, patients received TSEB. Four to 6 weeks after TSEB, they received a second course of 1.25 Gy. The cumulative TBI dose ranged from 2.5 to 3 Gy in about 3 months. Hemi-body irradiation (HB) with Co-60 (and a bolus) was given in cases of multiple regional tumors with large and thick infiltration of the skin to a dose of 9-12 Gy (using fractions of 1-1.5 Gy/day) which, once flattened, were boosted with whole-skin electron beam therapy (8 patients).

RESULTS

At 3 months, the overall response rate was 75% with 23/45 (51%) patients in complete response and 24% in partial response; one patient had stable lesions and 1 patient presented progressive disease. The overall response rate was 81% for T3 patients, 61% for T4, 79% for N1 and 70% for N3. The complete response rate was 67% for T3 and 28% for T4. Sixty-four percent of N1 patients and 41% of N3 had a complete response. The 5-year actuarial overall survival was 37% for T3 and 44% for T4 (P = 0.84). Patients with clinically abnormal lymph nodes that were pathologically negative (N1) presented a 5-year survival of 63%. Patients with pathologically positive lymph nodes (N3) experienced a 5-year survival rate of 32% (P = 0.040).

CONCLUSIONS

TSEB provides an excellent quality of life by reducing itching and discharge from the skin. Patients with more advanced disease may be treated and cured by the addition of photon beams in combination with TSEB. A selection of patients with advanced skin disease and regional extension may be cured by a combination of TSEB and photon beam irradiation. The regional treatment allows the use of electrons after the reduction of the plaques or thick tumors and a prophylactic irradiation of the adjacent nodal area.

Pentostatin in T-cell malignancies--a phase II trial of the EORTC. Leukemia Cooperative Group

PURPOSE

Within this phase II EORTC trial, we have investigated the safety and efficacy of pentostatin in lymphoid malignancies. We have previously reported the results in T- and B-cell prolymphocytic leukemia, B-cell chronic lymphocytic leukemia (B-CLL) and hairy cell leukemia. This report focuses on the outcome in T-cell malignancies: T-CLL, Sézary syndrome (Sézary), mycosis fungoides (MF) and T-zone lymphoma (TZL).

PATIENTS AND METHODS

Of the 92 patients with these diagnoses enrolled, 76 were evaluable for response and toxicity, i.e., 25 of 28 with T-CLL, 21 of 26 with Sézary, 22 of 26 with MF, and 8 of 12 with TZL. All patients had progressive and advanced disease. Pentostatin was administered at a dosage of 4 mg/m2 every week for the first 3 weeks, then 4 mg/m2 every 14 days for another 6 weeks, followed by maintenance therapy of 4 mg/m2 monthly for a maximum of 6 months.

RESULTS

Response rates (complete and partial responses) in patients with Sézary (n = 22) or MF (n = 21) were 33% and 23%, respectively, and in patients with T-CLL (n = 21) or TZL (n = 8) 8% and 25%, respectively. Sixteen (21%) patients died during the first ten weeks of treatment: twelve of progressive disease, two of infectious complications with progressive disease, one of myocard infarction and one of renal failure related to administration of i.v. contrast. Major toxicity (grade 3-4) included infection in 11% of patients, nausea/vomiting in 4%, diarrhea in 3%. Hematologic toxicity was mild to non-existent.

CONCLUSIONS

We conclude that pentostatin is active in Sézary and MF but showed marginal activity in T-CLL or TZL. Toxicities are mild to moderate at the dose schedule administered. Due to its relatively specific lympholytic effect and its favorable toxicity spectrum, pentostatin might be especially useful for the palliative treatment of T-cell malignancies.