The treatment of 45 patients with cutaneous T-cell lymphoma with low doses of interferon-alpha 2a and etretinate

Transitioning to Pegylated Interferon for the Treatment of Cutaneous T-Cell Lymphoma: Meeting the Challenge of Therapy Discontinuation and a Proposed Algorithm

Cutaneous T-cell lymphoma (CTCL) is an uncommon non-Hodgkin lymphoma characterized by skin involvement, with the most recognized subtypes being mycosis fungoides (MF) and Sezary syndrome (SS). Interferon has been an established treatment for MF/SS since 1984 and is integrated into management guidelines internationally. In 2019, manufacturers abruptly discontinued interferon-α2b and interferon-α2a. Many alternative systemic therapies in MF/SS remain unfunded or unavailable in Canada, presenting a unique challenge. Although off-label use of pegylated interferon is a logical substitute, there are no established dosing guidelines and limited published experience. This case series provides a single-center experience on pegylated interferon-α2b for treatment of MF/SS, a suggested management algorithm, and a review of the literature. All patients identified in the Calgary Cutaneous Lymphoma Program with stage IIB–IVB MF/SS treated with interferon-α2b (4.5–9 MU/week) were switched to once weekly pegylated interferon (90 μg, 0.5 mL) between February and July 2021. Response was monitored using the mSWAT and SkinDex-29 tools. Eight patients were switched to pegylated interferon, with a median disease duration of 69 months (range: 8–275 months). Five out of eight patients remain on pegylated interferon, with the remainder having switched to preplanned therapies. Two patients required dose reduction due to side effects, including grade II anemia and mood changes. The remaining patients had normal laboratory investigations and no additional side effects. Uncommon lymphomas like MF/SS have limited treatment options, and the impact of abrupt product discontinuation is substantial. We propose a management algorithm for the transition of patients from interferon to pegylated interferon.

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.

Systematic review of combination therapies for mycosis fungoides

BACKGROUND

A variety of therapeutic options are available for mycosis fungoides, the most prevalent subtype of cutaneous T cell lymphomas, but thus far, no regimen has been proven to be curative. A combination of treatments is a well-established strategy to increase the therapeutic efficacy. However, data from clinical trials analyzing such combinations for the treatment of mycosis fungoides are scarce.

OBJECTIVE

To analyze the available evidence on combination therapies with emphasis on the combination of psoralen with UVA phototherapy (PUVA), interferon-alpha and bexarotene with another treatment.

METHODS

Systematic literature review of the databases Embase, Cochrane, Medline, and Medline in Process.

RESULTS

Combination of PUVA with interferon-alpha or retinoids did not result in an increased overall response rate. Addition of methotrexate but not retinoids to interferon-alpha may increase the overall response rate. Bexarotene was investigated in one trial each with vorinostat, methotrexate or gemcitabine, whereby only methotrexate possibly enhanced the effect of bexarotene.

CONCLUSION

For mycosis fungoides, no combination treatment has been demonstrated to be superior to monotherapy. Based on our analysis, we conclude that in certain clinical situations, patients may benefit from a combination of PUVA with interferon-alpha or a retinoid or a combination of the latter two. Furthermore, patients in advanced stages may benefit from the combination of methotrexate and interferon-alpha or bexarotene. Finally, the combination of bexarotene with either vorinostat or gemcitabine did not increase the overall response rate but resulted in more pronounced side effects and cannot be recommended.

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.

Follicular mucinosis associated with early stage cutaneous T-cell lymphoma: successful treatment with interferon alpha-2b and acitretin

BACKGROUND

Follicular mucinosis (FM) is a rare dermatosis characterized by mucin deposits in the pilosebaceous units. It is divided into a primary-benign type and a secondary type associated mostly with lymphomas. No standard effective therapy is available for the primary FM while in the secondary form treatment is aimed against the underlying disease.

METHODS

We report a case of secondary FM in which a cutaneous T-cell lymphoma was detected 6 years after the initial eruption.

RESULTS

Complete remission was achieved with combination therapy of interferon alpha-2b at a dose of 6 million U subcutaneously three times a week, and acitretin 35 mg/day, for 6 months.

CONCLUSION

Regular clinical and histopathological evaluation is suggested for all patients with FM. For cases associated with cutaneous T-cell lymphoma the combination of interferon alpha and acitretin seems to be a good therapeutical approach.

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.

The optimal use of bexarotene in cutaneous T-cell lymphoma

The management goal in cutaneous T-cell lymphomas (CTCLs) is to improve symptoms and induce remission. Early-stage disease is generally treated with skin-directed therapies. However, if these do not control the disease, systemic therapy becomes necessary. Bexarotene, a novel rexinoid, is an oral, noncytotoxic drug that has been approved in Europe for the treatment of refractory advanced-stage CTCL and in the U.S.A. for refractory CTCL. We provide guidance on the use of bexarotene in the management of CTCL, based on data from phase II/III clinical trials and the authors' clinical experience, and suggest how the potential of the drug can be maximized. The clinical trial results with bexarotene are reviewed, especially in comparison with interferon-alpha, which is the other commonly used noncytotoxic systemic therapy for CTCL. A treatment algorithm for bexarotene in refractory CTCL is suggested. As bexarotene may take time to achieve a maximum response, this algorithm recommends that therapy should be continued for a sufficient period to allow for a delayed onset of action. In addition, possible combination therapies with bexarotene are discussed. We conclude that bexarotene is effective in the management of CTCL, and has the advantage of oral administration. An on-going randomized clinical trial comparing psoralen plus ultraviolet A (PUVA) with PUVA plus bexarotene will provide valuable information about this combination regimen in early-stage disease, but further data are needed on the relative efficacies of other combination therapies with bexarotene in CTCL.

Off-label uses of biologics in dermatology: Interferon and intravenous immunoglobulin (Part 1 of 2)

The introduction of a number of biologic therapies into the market has revolutionized the practice of dermatology. These therapies include interferons, intravenous immunoglobulin, infliximab, adalimumab, etanercept, efalizumab, alefacept, and rituximab. Most dermatologists are familiar with the Food and Drug Administration-approved indications of these medications. However, numerous off-label uses have evolved. As part 1 of a 2-part series, this article will review the literature regarding the off-label uses of the interferons and intravenous immunoglobulin in dermatology.

Bexarotene in the treatment of cutaneous T-cell lymphoma

Primary cutaneous T-cell lymphomas encompass a spectrum of non-Hodgkin's lymphomas that are characterised by clonal proliferation of skin-homing malignant T lymphocytes. Mycosis fungoides and the leukaemic variant Sézary syndrome, collectively referred to as cutaneous T-cell lymphomas, are the most common entities. No curative therapy exists and patients ultimately develop advanced or relapsed disease that is refractory to standard treatment options. Therefore, there is a great need for the development of novel emerging therapies. Bexarotene is the first synthetic nuclear retinoid X receptor-selective retinoid approved by the FDA for the treatment of refractory cutaneous T-cell lymphoma in all stages, as both an oral capsule and a topical gel formulation. Bexarotene was found to induce apoptosis in a variety of preclinical in vitro and in vivo models including cutaneous T-cell lymphoma cells, and has shown efficacy in two multi-centre, open-label Phase II - III clinical trials for early and advanced stages of cutaneous T-cell lymphoma in patients who have failed or were refractory to standard therapies. New insights into the immunomodulatory function of bexarotene have indicated opportunities for combined treatment with IFN-alpha, denileukin diftitox or phototherapy. This article reviews the biological properties, pharmacokinetics, clinical efficacy, safety and role of bexarotene in the treatment of cutaneous T-cell lymphoma.

EORTC consensus recommendations for the treatment of mycosis fungoides/Sézary syndrome

Several reviews and guidelines on the management of mycosis fungoides and Sézary syndrome (MF/SS) have been published; however, treatment strategies for patients with MF/SS vary from institution to institution and no European consensus has yet been established. There are few phase III trials to support treatment decisions for MF/SS and treatment is often determined by institutional experience. In order to summarise the available evidence and review 'best practices' from each national group, the European Organisation for Research and Treatment of Cancer (EORTC) Cutaneous Lymphoma Task Force met in September 2004 to establish European guidelines for the treatment of MF/SS. This article reviews the treatment regimens selected for inclusion in the guidelines and summarises the clinical data for treatments appropriate for each stage of MF/SS. Guideline recommendations are presented according to the quality of supporting data, as defined by the Oxford Centre for Evidence-Based Medicine. Skin-directed therapies are the most appropriate option for early-stage MF/SS and most patients can look forward to a normal life expectancy. Patients with advanced disease should be encouraged to participate in clinical trials and maintenance of quality of life should be paramount.

Comparison of selective retinoic acid receptor– and retinoic X receptor–mediated efficacy, tolerance, and survival in cutaneous t-cell lymphoma

Primary cutaneous T-cell lymphomas are non-Hodgkin's lymphomas with varied clinical presentation and prognosis. The most common subtypes of cutaneous T-cell lymphomas are the epidermotropic variants mycosis fungoides and Sézary syndrome. Treatment of mycosis fungoides has encompassed a variety of modalities including the use of retinoids with several studies evaluating their efficacy. The reported benefits and duration of response have varied in published data. The biological effect of retinoids is mediated by specific receptor families, retinoic acid receptor (RAR) and retinoic X receptor (RXR), with subsequently altered gene expression. There are no data available on cutaneous T-cell lymphomas that compare RAR and RXR retinoids. The objective of our retrospective, nonrandomized, single-center study was to compare the response, survival outcomes, and toxic effects in our phase II trial of the RAR-specific retinoid, all-trans retinoic acid, with clinical use of the RXR-specific retinoid, bexarotene, in patients with mycosis fungoides/Sézary syndrome who have relapsed. There was no statistical difference in response rates (12% vs 21%), response duration (20.5 vs 7.3 months), event-free survival time (4 vs 5 months), or median survival when corrected for length of follow-up. Both have favorable toxicity profiles that can be managed with medications. The toxicity profile caused by bexarotene seems to be more limited to laboratory values and better tolerated, although generally associated with more severe grades of toxicity. In conclusion, both retinoids have modest objective response rates and, therefore, most likely will have limited impact as monotherapeutic agents. However, the immunomodulatory effects of RAR and RXR retinoids provide a rational basis for using retinoids in combination with other biologic immune response modifiers, phototherapy, or cytotoxic chemotherapy.

Low-dose oral bexarotene in combination with low-dose interferon alfa in the treatment of cutaneous T-cell lymphoma: clinical synergism and possible immunologic mechanisms

BACKGROUND

For nearly 2 decades clinicians have been treating cutaneous T-cell lymphoma (CTCL) with regimens that combine interferon alfa with retinoid compounds. In December 1999 a new retinoid, bexarotene, was approved by the US Food and Drug Administration for the treatment of CTCL. At the manufacturer's recommended dose of bexarotene (300 mg/m(2) of body surface area), it has proven to be a highly effective therapy for all stages of CTCL. Nevertheless, this dose is typically associated with adverse effects including severe hyperlipidemia. Furthermore, there appears to be no standardization of dosing among physicians who treat CTCL.

OBSERVATIONS

We present 3 representative patients, 2 with erythrodermic CTCL and 1 with follicular mycosis fungoides, who experienced the rapid clearing of skin disease while being treated with a combination of low-dose bexarotene and low-dose recombinant interferon alfa.

CONCLUSIONS

Combining low-dose bexarotene with low-dose interferon alfa was well tolerated and led to rapid improvement in our patients. We review the clinical and biologic basis for this approach.

Activity of interferon-alpha and isotretinoin in patients with advanced, refractory lymphoid malignancies

BACKGROUND

Interferon-alpha (IFN-alpha) and retinoids have shown nonoverlapping toxicity and each has shown antitumor activity in patients with lymphoma. The aim of the current study was to assess the toxicity, safety, and efficacy of IFN-alpha combined with isotretinoin in patients with advanced, refractory lymphoid malignancies.

METHODS

Adults with biopsy-proven advanced lymphoid malignancy were treated. Patients with compromised bone marrow function (platelet counts as low as 30 x 10(9)/L) were eligible. Treatment was comprised of IFN-alpha at a starting daily dose of 3 mega units subcutaneously and isotretinoin orally starting at a dose of 1 mg/kg daily in 2 divided doses.

RESULTS

Forty-four patients were evaluable. Their median age was 57 years (range, 18-82 years). Eighteen patients had advanced cutaneous T-cell lymphoma, 6 patients had peripheral T-cell lymphoma, 14 patients had Hodgkin disease, and 6 patients had a variety of other lymphoid malignancies. Patients with Hodgkin disease had received a median of 6 previous therapies (range, 3-12 therapies) and patients with other lymphoid malignancies had received a median of 4 previous therapies (range, 1-9 therapies). The median duration of treatment was 4 months (range, 0.25-38 months). The overall response rate was 38.6% (complete response in 5 patients [11.3%] and partial response in 12 patients [27.3%]). The median response duration was 3 months (range, 1-95+ months). The most common toxicities were low-grade fever, flu-like symptoms, and fatigue (IFN-alpha effects); dry mouth and skin and hypertriglyceridemia (cis-retinoic acid effects); and thrombocytopenia (which generally occurred in patients with low baseline platelet counts).

CONCLUSIONS

IFN-alpha and isotretinoin combination therapy had antitumor activity and was well tolerated in heavily pretreated patients with lymphoid malignancies.

Retinoids: therapeutic applications and mechanisms of action in cutaneous T-cell lymphoma

Retinoids, natural and synthetic derivatives of vitamin A, are biological regulators of differentiation, proliferation, apoptosis, and immune response. Retinoic-acid-receptor-selective retinoids (all-trans retinoic acid, 13-cis-retinoic acid, and the synthetic analogs isotretinoin, etretinate and acitretin) have been used for years as monotherapy and/or in combination for treatment of cutaneous T-cell lymphoma (CTCL). Orally administered bexarotene, the first synthetic highly selective retinoid-X-receptor retinoid to be approved by the FDA for CTCL, was shown to be active against the cutaneous manifestations of all stages of CTCL. The topical gel formulation was also effective for early cutaneous manifestations of CTCL or as an adjunct to systemic or phototherapy. Bexarotene treatment induces apoptosis of CTCL cells with down-regulation of its receptors and of survivin, an inhibitor of apoptosis. Identification of new receptor subtype-selective retinoids, combination of various receptor-selective retinoids or other agents, and a new drug delivery system may improve the clinical efficacy of retinoids in the future.

Analysis of long-term outcomes of combined modality therapy for cutaneous T-cell lymphoma

BACKGROUND

Although cutaneous T-cell lymphoma (CTCL), including mycosis fungoides (MF) and Sézary syndrome, is often responsive to treatment, few current therapies increase survival or consistently induce durable remissions, especially in advanced disease.

OBJECTIVE

In an effort to improve treatment efficacy and outcome in CTCL, a combined modality protocol using 3 to 4 consecutive phases of therapy was initiated in 1987 at M.D. Anderson Cancer Center, Houston, Tex.

METHODS

During a period of 15 years between 1987 and 2001, 95 patients with early-stage (Ia-IIa, n = 50) and late-stage (IIb-IVb, n = 45) MF were treated with subcutaneous interferon-alpha and oral isotretinoin, followed by total-skin electron beam therapy, and long-term maintenance therapy with topical nitrogen mustard and interferon-alpha. Patients with late-stage (IIb-IVb) disease also received 6 cycles of combination chemotherapy before electron beam therapy.

RESULTS

Combined modality therapy yielded a response rate of 85% with a 60% complete response rate. Among 38 patients with early-stage disease and 18 patients with late-stage disease achieving complete response, 9 (24%) patients with early-stage MF and 3 (17%) patients with late-stage MF achieved sustained remissions lasting more than 5 years. The median disease-free survival (DFS) for early and late stages of disease was 62 and 7 months, with 5-year Kaplan-Meier estimated rates of 50% and 27%, respectively. Current median overall survival times on combined modality are 145 months for patients with early-stage disease and 36 months for those with late-stage disease. Death was attributable to CTCL disease in 17 (55%) of 31 cases. The Kaplan-Meier estimates for 5-year survival are 94% for early-stage and 35% for late-stage disease. Univariate survival analysis in this patient population reveals statistically significant associations of clinical stage with overall response rates (P =.02), DFS (P =.03), and overall survival (P <.0001); age with DFS (P =.001) and overall survival (P =.04); and T stage (P <.0001) and lactate dehydrogenase (P =.007) with overall survival. By multivariate analysis using a Cox proportional hazards model, only age was significantly associated with DFS (hazard ratio 2.9), and only stage with overall survival (hazard ratio 18.2).

CONCLUSION

This nonrandomized and uncontrolled CTCL study gives supportive evidence that this multiphased combined modality regimen is well tolerated and may yield higher response rates and DFS than total-skin electron beam therapy alone, but provides no evidence for a change in survival.

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.

Practical evaluation and management of cutaneous lymphoma

Accurate evaluation of patients with suspected or known cutaneous lymphoma requires the integration of many sources and types of information, including clinical evaluation, microscopic analysis of tissue, immunophenotyping, gene rearrangement studies, clinical staging, and longitudinal observation. Diagnoses should be based on knowledge of specific lymphoma types as described in modern classification systems. Management of patients with cutaneous lymphoma requires collaboration among dermatologists, dermatopathologists, hematopathologists, and medical, surgical and radiation oncologists. (J Am Acad Dermatol 2002;46:325-57.)

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should better understand how to evaluate and manage patients for suspected or established lymphoma of the skin. Components include the clinical history and physical examination, optimal biopsy and tissue handling, interpretation of pathology and adjunctive test results, clinicopathologic correlation, and therapy. Participants should also understand the basis for establishing a specific diagnosis of cutaneous lymphoma based on current classification and staging.

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.

Bexarotene is effective and safe for treatment of refractory advanced-stage cutaneous T-cell lymphoma: multinational phase II-III trial results

PURPOSE

Cutaneous T-cell lymphomas (CTCL) are malignancies of T cells appearing as skin lesions and are responsive to retinoid therapy. Safety and efficacy of a novel RXR-selective retinoid (rexinoid) bexarotene (Targretin, LGD1069; Ligand Pharmaceuticals Inc, San Diego, CA) was evaluated as a single-agent oral therapy administered once daily in an open-label study in patients with refractory advanced-stage CTCL.

PATIENTS AND METHODS

Ninety-four patients with biopsy-confirmed CTCL in advanced stages (IIB-IVB) were enrolled at 26 centers. Fifty-six patients received an initial dose of 300 mg/m2/d oral bexarotene and 38 started at more than 300 mg/m2/d.

RESULTS

Clinical complete and partial responses were reported by Primary End point Classification for the study in 45% (25 of 56) of patients enrolled at 300 mg/m2/d dosing. At more than 300 mg/m2/d, 55% (21 of 38) of patients responded, including 13% (five of 38) clinical complete. For the 300 mg/m2/d initial dose group, the rate of relapse after response was 36% and the projected median duration of response was 299 days. Improvements were also seen in overall body-surface area involvement, median index lesion surface area, adenopathy, cutaneous tumors, pruritus, and CTCL-specific quality of life. The most frequent drug-related adverse events included hypertriglyceridemia (associated rarely with pancreatitis), hypercholesterolemia, hypothyroidism, and headache.

CONCLUSION

Bexarotene is the first in a novel class of pharmacologic agents, the RXR-selective retinoids, or rexinoids. Bexarotene is orally administered, safe, and generally well tolerated with reversible side effects, and is effective for the treatment of advanced, refractory CTCL.

Serological detection of cutaneous T-cell lymphoma-associated antigens

Cutaneous T-cell lymphomas (CTCL) are a group of skin neoplasms that originate from T lymphocytes and are difficult to treat in advanced stages. The present study is aimed at the identification of tumor-specific antigens from a human testis cDNA library using human sera known as the SEREX (serological identification of recombinantly expressed genes) approach. A cDNA library from normal testicle tissue was prepared and approximately 2 million recombinants were screened with sera from Sézary Syndrome and Mycosis fungoides patients. A total of 28 positive clones belonging to 15 different genes/ORFs were identified, including five hitherto unknown sequences. Whereas control sera did not react with most clones, 11-71% sera from CTCL patients were reactive against the identified clones. Expression analysis on 28 normal control and 17 CTCL tissues by reverse transcription-PCR (RT-PCR) and Northern blotting revealed seven ubiquitously distributed antigens, six differentially expressed antigens (several normal tissues were positive), and two tumor-specific antigens that were expressed only in testis and tumor tissues: (i) A SCP-1-like sequence, which has already been detected in various tumors, has been found in one CTCL tumor and four sera of CTCL patients reacted with various SCP-1-like clones and (ii) a new sequence named cTAGE-1 (CTCL-associated antigen 1) was detected in 35% of CTCL tumor tissues and sera of 6/18 patients reacted with this clone. The present study unravels CTCL-associated antigens independent of the T-cell receptor. The SCP-1-like gene and cTAGE-1 were shown to be immunogenic and immunologically tumor-specific and may therefore be candidates for immunotherapy targeting CTCL.

Serological detection of cutaneous T-cell lymphoma-associated antigens

Cutaneous T-cell lymphomas (CTCL) are a group of skin neoplasms that originate from T lymphocytes and are difficult to treat in advanced stages. The present study is aimed at the identification of tumor-specific antigens from a human testis cDNA library using human sera known as the SEREX (serological identification of recombinantly expressed genes) approach. A cDNA library from normal testicle tissue was prepared and approximately 2 million recombinants were screened with sera from Sézary Syndrome and Mycosis fungoides patients. A total of 28 positive clones belonging to 15 different genes/ORFs were identified, including five hitherto unknown sequences. Whereas control sera did not react with most clones, 11-71% sera from CTCL patients were reactive against the identified clones. Expression analysis on 28 normal control and 17 CTCL tissues by reverse transcription-PCR (RT-PCR) and Northern blotting revealed seven ubiquitously distributed antigens, six differentially expressed antigens (several normal tissues were positive), and two tumor-specific antigens that were expressed only in testis and tumor tissues: (i) A SCP-1-like sequence, which has already been detected in various tumors, has been found in one CTCL tumor and four sera of CTCL patients reacted with various SCP-1-like clones and (ii) a new sequence named cTAGE-1 (CTCL-associated antigen 1) was detected in 35% of CTCL tumor tissues and sera of 6/18 patients reacted with this clone. The present study unravels CTCL-associated antigens independent of the T-cell receptor. The SCP-1-like gene and cTAGE-1 were shown to be immunogenic and immunologically tumor-specific and may therefore be candidates for immunotherapy targeting CTCL.

Primary cutaneous T-cell lymphoma: review and current concepts

PURPOSE

Primary cutaneous T-cell lymphomas (CTCLs) encompass a wide variety of lymphomas that are characterized by the localization of the malignant lymphocytes to the skin at presentation. Advances in molecular biologic techniques, including immunophenotyping and gene rearrangement studies to determine clonality, have led to more frequent diagnosis of CTCL as well as more consistent subclassification of these entities. However, there continues to be confusion in the classification, prognosis, and management of patients with CTCL. The purpose of this review is to present a summary of the diagnosis, prognosis, and treatment of CTCL, with specific emphasis on mycosis fungoides (MF) and Sézary syndrome (SS). We also present a detailed discussion of the entities that make up the differential diagnosis of CTCL.

DESIGN

We reviewed the medical literature on CTCL and other diseases that make up the differential diagnosis of CTCL.

RESULTS AND CONCLUSION

MF and SS are the most common forms of CTCL. The etiology of this disease is still unknown. Patients may go for months to years with skin abnormalities before being diagnosed. MF/SS is an indolent disease and patients with T1 disease have a normal life expectancy. Patients who undergo transformation to large-cell lymphoma (8% to 23% of patients) have a poor prognosis, with mean survival ranging from 2 to 19 months. Treatment for MF/SS continues to be palliative. There are many new therapies that are currently being investigated in clinical trials, and the DAB(389)IL-2 fusion protein was recently approved for the treatment of refractory MF/SS.

Antiangiogenic strategies and agents in clinical trials

The understanding that the growth of tumors depends on the acquisition of a blood supply has led to the development of new therapies for cancer and other angiogenic diseases based on inhibition of neovascularization. This review examines the role of angiogenesis in cancer progression and describes various strategies for interfering with this process. The developmental status of angiogenesis inhibitors in human clinical trials is presented, including their proposed mechanisms of action. Standard chemotherapeutic agents and angiogenesis inhibitors are compared, noting that different end points might need to be considered in clinical trials and that drug resistance may be less of a problem with antiangiogenic therapy than with conventional chemotherapy regimens. The suggestion is made that cytotoxic chemotherapy and angiogenesis inhibitors used in combination may produce complementary therapeutic benefits in the treatment of cancer.

Depressed IL-12-Mediated Signal Transduction in T Cells from Patients with Sézary Syndrome Is Associated with the Absence of IL-12 Receptor β2 mRNA and Highly Reduced Levels of STAT4

Sézary syndrome (SS) is the leukemic phase of cutaneous T cell lymphoma characterized by the proliferation of clonally derived CD4+ T cells that release cytokines of the Th2 T cell phenotype (IL-4, IL-5, IL-10), whereas Th1 T cell cytokines (IL-2, IFN-γ) are markedly depressed as is expression of IL-12, a pivotal cytokine for Th1 cell differentiation. Normal Th1 cells express both the β1 and β2 chains of the IL-12 receptor (IL-12R) and tyrosine phosphorylate STAT4 in response to IL-12. Th2 T cells express only the IL-12R β1 and thus do not tyrosine phosphorylate STAT4 in response to IL-12. To determine whether SS cells are Th2-like at the level of IL-12 signal transduction, we analyzed RNA from seven patients for the presence of message for the IL-12R β1 and β2 genes using RNase protection assays and assessed whether IL-12 induced tyrosine-phosphorylation of STAT4 by immunoblotting. In PBL from six of seven SS patients tested, β2 message was expressed at low to undetectable levels and its expression could not be stimulated by either IFN-α or IFN- γ, which stimulated β2 expression in control PBL. The absence of β2 expression is further supportive evidence for the Th2 lineage of SS cells. However, unlike normal Th2 cells, SS cells also showed severely reduced levels of STAT4, suggesting that they have a depressed response to any inducer of the STAT4 signal transduction pathway, including IFN-α. This is the first observation linking STAT4 gene expression with a human disease and suggests that dysregulation of STAT4 expression may be significant to the development and/or progression of SS.

Long-term follow-up in 51 patients with mycosis fungoides and Sézary syndrome treated by interferon-alfa

Although interferon-alfa (IFN-alpha) has proved effective in treating epidermotropic cutaneous T-cell lymphoma (ECTL), few studies have considered the follow-up of treated patients and whether complete remission was maintained. We studied 51 patients (one stage Ia, seven stage Ib, one stage IIa, 30 stage IIb, 11 stage III (Sézary syndrome) and one stage IV) who received low-dose IFN-alpha as monotherapy for ECTL (mean daily dose of IFN-alpha 2.7 x 106 units for 14.9 months), giving special consideration to the significance of My7 (CD13) antigen expression by epidermal basal cells in predicting the maintenance of complete remission. For a mean follow-up period of 43.4 months, the results showed 21 complete remissions, 13 partial remissions and 17 patients with stable or progressive disease. Twelve patients died during the follow-up (3-52 months). IFN-alpha led to an improved response in the early stages, with a greater number of complete remissions (P = 0.03) and partial remissions (P = 0.01). The mean time to complete remission was 4 months, regardless of clinical stage (P = 0.1). Of 21 patients in complete remission, 57% had a relapse within a mean period of 7.5 months. For patients maintained in complete remission, the mean period of response was 31 months. The length of complete remission was independent of clinical stage, and My7 antigen expression was not predictive of complete remission.

Phenotypic, morphologic changes and Ig secretion induced on B-NHL cells in vitro by interferon alpha and all-trans-retinoic acid: possible progression toward a more differentiated state

Twenty-five B-cell-nonHodgkin's lymphomas (B-NHL): 6 lymphocytic, 2 centrocytic, 13 follicular, centrocytic/centroblastic, 2 lymphoplasmocytoid and 2 centroblastic were tested for their ability to acquire features of mature plasma cells under the effect of interferon alpha (final concentration, 600 UI/ml), all-trans-retinoic-acid (ATRA) (final concentration, 10(-6) mol/l) and the association of both. B-NHL cells were negatively purified (>99%) by an immunomagnetic method, cultured for 7 d with or without interferon and ATRA, then stained with anti-CD19, CD20, surface Ig, DR, CD38 and with anti-CD138 (syndecan-1) antibody-recognizing plasma cells. Ig production was estimated in culture supernatants by an ELISA method and changes in cell morphology were investigated on May-Grunwald-Giemsa-stained cytospin preparations. In all cases interferon and ATRA, alone or in association, were able to induce changes in the immunophenotypic profile, associated or not with morphologic changes and induction of Ig secretion. All changes were greatly variable from one to the other B-NHL sample and no relationship could be found between a particular pattern of change and the histological subtype. Interferon alpha was more potent than ATRA in inducing changes. In favour of a differentiation process, we observed a concomitant decrease of DR expression and increase of CD38 expression in 8 cases with interferon alpha, and in 4 cases with ATRA. Although interferon- or ATRA-treated cells did not display cytologic, functional features and changes of the immunophenotypic profile fully compatible with those of terminally differentiated cells, these results suggest a possible transition toward more differentiated elements, especially with interferon alpha.

Biological modifiers (etretinate (changed from etetrinate) and alfa 2a) in the treatment of refractory cutaneous T-cell lymphoma

To assess the efficacy and toxicity of biological modifiers in combination etetrinate, 0.8 mg/kg/day, po and interferon alfa 2a 9.0 MU, three times at week) in the treatment of refractory cutaneous T-cell lymphoma (CTLC) we began a clinical study on 12 heavily treated patients. After 1 year on treatment 10/12 patients (83%) achieved complete response. Two patients were considered failures with disease progression. After a median follow-up of 3 years, seven patients (56%) remained in complete remission. Toxicity was mild. All patients received 93% of the planned dose of etetrinate and interferon. We feel that biological modifiers, as etetrinate and interferons, are agents with limited hematological toxicity even in higher doses. The combination of two agents, with different mechanisms of action, could improve the outcome in patients with refractory CTCL. Controlled trials are necessary to define the roles of this type of therapy as first line of treatment.

New perspectives in experimental and clinical research for cutaneous T cell lymphomas

Cutaneous T cell lymphomas (CTCL) are lymphoproliferative disorders, which can be classified by an adaptation of the Kiel classification. The most common CTCL, Mycosis fungoides (MF) and Sézary syndrome (SS), are monoclonal T helper memory lymphomas. They belong to the group of peripheral T cell lymphomas. However, CTCL includes other disease entities such as granulomatous slack skin, pagetoid reticulosis, and lipotropic CTCL. Polymerase chain reaction of the T cell receptor (TCR)-gamma and screening of the PCR products for sequence-specific mobility in acrylamide gels has increased the detection limit for clonal T cells in the skin. This method will help to define the relationship of CTCL to other lymphoproliferative disorders and may contribute to the early diagnosis of CTCL. In SS, the malignant CTCL clone secretes a T helper-2 cytokine pattern, which might be responsible for the systemic immunosuppression in CTCL patients. New treatment modalities (IL-12) might correct these immunologic abnormalities. Cutaneous B cell lymphomas mostly are follicular center cell derived and usually have a good prognosis. Therapy of cutaneous lymphomas should take into account prognostic factors, the most reliable of which in CTCL is the tumor mass expressed by the tumor burden index.

Interferon-alpha (INF-alpha) and etretinate in the treatment of mycosis fungoides

A combination therapy of mycosis fungoides (MF) with interferon-alpha (INF-alpha) and etretinate was reported. A 53-year-old patient suffering from MF was treated with intramuscular administration of INF-alpha at a dosage of 9 x 10(6) IU daily; skin lesions poorly responded to the treatment. After oral etretinate with a dosage of 50 mg daily was combined with INF-alpha, marked clinical improvement was seen in skin lesions with minor side effects. INF-alpha in combination with etretinate can have beneficial effects in the treatment of MF.

Topical administration of hexadecylphosphocholine in patients with cutaneous lymphomas: results of a phase I/II study

BACKGROUND

Hexadecylphosphocholine is a new antineoplastic drug that inhibits tumor cell growth directly and, in addition, might have immunoregulatory properties.

OBJECTIVES

We investigated the topical application of this phospholipid in patients with cutaneous lymphoma.

METHODS

Twenty-four patients with histologically documented cutaneous lymphoma were treated for 8 weeks. Lesions that responded to treatment were biopsied and evaluated histologically.

RESULTS

Of 15 patients with cutaneous T-cell lymphomas, 12 were evaluable. Two complete remissions, four partial remissions, and one minor remission were observed. Of seven patients with B-cell lymphomas, six were evaluable. One complete remission, three partial remissions, one case of stable disease, and one case of progressive disease were seen. However, histologic monitoring demonstrated only a partial clearing of infiltrating lymphocytes in lesions that showed a partial or complete response clinically. Both patients with lymphomatoid papulosis had complete clearing of the lesions clinically. An objective response rate (partial and complete response) of 56% (10/18) was achieved in the patients with cutaneous lymphoma who were treated in this study.

CONCLUSION

Hexadecylphosphocholine appears to be effective topically in the treatment of some cases of cutaneous lymphomas.

Interferon treatment of cutaneous T-cell lymphoma

In this report we have reviewed studies on the clinical effect of the interferon (IFN) treatment of 304 patients suffering from cutaneous T-cell lymphoma (CTCL). Intramuscular, subcutaneous or intralesional administration of recombinant IFN has been used as monotherapy or as part of combination therapy. In general, IFN has proved to be a relatively effective agent in the treatment of CTCL, and the best responses have been achieved in the early stages of the disease. In CTCL the overall response rate to IFN including complete, partial and minor responses is 70%. Neither the doses nor the routes of administration in these studies has any statistically significant influence on the clinical response to IFN treatment. Continuous low-dose IFN therapy, presumably in combination with psoralen and UVA light (PUVA), is recommended. This review concludes that the clinical stage of disease before treatment is the only known predictive parameter concerning the clinical response to IFN treatment in patients with CTCL.

Roferon-A (interferon alpha 2a) combined with Tigason (etretinate) for treatment of cutaneous T cell lymphomas

Many treatments are used for epidermotropic cutaneous T cell lymphomas (CTCL) such as mycosis fungoides (MF) and Sézary syndrome (SS). All pretend to be effective, but none is really curative. As single drug therapy provides a response rate of about 55% with interferon alpha and about 45% with etretinate, we studied the effectiveness of combining these two drugs for immunomodulatory therapy in epidermotropic CTCL. A review of four reports, including a multicenter study performed in 45 patients, indicates a response rate of 56%, with better results for MF than SS. Side effects are generally moderate when low doses are used. The mechanism of action of this combined therapy on cutaneous lesions remains unclear. In vitro, a synergistic effect of retinoids on interferon alpha antiviral activity has been demonstrated, and in vivo an immunohistochemical study showed that the combined therapy modulates antigens expressed by keratinocytes and increases cytotoxic cells in dermis without modifying the number of Langerhans cells in epidermis.

Intramuscular low dose alpha-2B interferon and etretinate for treatment of mycosis fungoides

BACKGROUND

Mycosis fungoides is a lymphoma of cutaneous origin characterized by a proliferation of cells with a T phenotype.

METHODS

In this pilot study, 13 men with mycosis fungoides in various stages were treated with alpha-2b interferon and etretinate.

RESULTS

In ten of them, such a therapy proved to be effective (7 complete responses, 3 partial responses), sometimes with prolonged remissions (up to 20 months, and still persistent) after suspension of the drugs.

CONCLUSIONS

We chose low-dose interferon administration in order to prevent side effects, which are said to be dose-dependent. In our experience this is not true, but this drawback seems to be overcome by the very good, sometimes spectacular, response to this combination therapy, particularly in low stage forms of the disease. This fact, compared with results provided by other groups, prompts us to plan new research protocols based on associations of retinoids with different interferon types (or even associations of different interferons), because we believe they will have an important place in treatment of cutaneous T-cell lymphoma in future.