The occurrence of vitiligo after psoralens and ultraviolet a therapy

Guidelines for phototherapy of mycosis fungoides and Sézary syndrome: A consensus statement of the United States Cutaneous Lymphoma Consortium

BACKGROUND

Ultraviolet light (UVL) is a long established treatment for mycosis fungoides (MF) and Sézary syndrome (SS), subtypes of cutaneous T-cell lymphoma (CTCL). Treatments have traditionally included broadband, narrowband ultraviolet B light (UVB) and psoralen plus ultraviolet A light photochemotherapy (PUVA), but more recently, treatment options have expanded to include UVA1 and excimer laser. UVL is used either as monotherapy or as an adjuvant to systemic therapy, demonstrating efficacy in many cases that equal or surpass systemic medications. Despite its utility and duration of use, the current practice of using UVL guidelines for psoriasis to treat patients with MF/SS is problematic because the goals of prolonging survival and preventing disease progression are unique to CTCL compared to psoriasis.

OBJECTIVES

We sought to develop separate guidelines for phototherapy for MF/SS for both clinical practice and for clinical trials.

METHODS

Literature review and cutaneous lymphoma expert consensus group recommendations.

RESULTS

This paper reviews the published literature for UVB and UVA/PUVA in MF/SS and suggests practical standardized guidelines for their use.

LIMITATIONS

New standardization of phototherapy.

CONCLUSIONS

These guidelines should allow the comparison of results with phototherapy in MF/SS across different stages of patients, centers, and in combination with other agents in practice and in clinical trials.

Paradoxical and bidirectional drug effects

A paradoxical drug reaction constitutes an outcome that is opposite from the outcome that would be expected from the drug's known actions. There are three types: 1. A paradoxical response in a condition for which the drug is being explicitly prescribed. 2. Paradoxical precipitation of a condition for which the drug is indicated, when the drug is being used for an alternative indication. 3. Effects that are paradoxical in relation to an aspect of the pharmacology of the drug but unrelated to the usual indication. In bidirectional drug reactions, a drug may produce opposite effects, either in the same or different individuals, the effects usually being different from the expected beneficial effect. Paradoxical and bidirectional drug effects can sometimes be harnessed for benefit; some may be adverse. Such reactions arise in a wide variety of drug classes. Some are common; others are reported in single case reports. Paradoxical effects are often adverse, since they are opposite the direction of the expected effect. They may complicate the assessment of adverse drug reactions, pharmacovigilance, and clinical management. Bidirectional effects may be clinically useful or adverse. From a clinical toxicological perspective, altered pharmacokinetics or pharmacodynamics in overdose may exacerbate paradoxical and bidirectional effects. Certain antidotes have paradoxical attributes, complicating management. Apparent clinical paradoxical or bidirectional effects and reactions ensue when conflicts arise at different levels in self-regulating biological systems, as complexity increases from subcellular components, such as receptors, to cells, tissues, organs, and the whole individual. These may be incompletely understood. Mechanisms of such effects include different actions at the same receptor, owing to changes with time and downstream effects; stereochemical effects; multiple receptor targets with or without associated temporal effects; antibody-mediated reactions; three-dimensional architectural constraints; pharmacokinetic competing compartment effects; disruption and non-linear effects in oscillating systems, systemic overcompensation, and other higher-level feedback mechanisms and feedback response loops at multiple levels. Here we review and provide a compendium of multiple class effects and individual reactions, relevant mechanisms, and specific clinical toxicological considerations of antibiotics, immune modulators, antineoplastic drugs, and cardiovascular, CNS, dermal, endocrine, musculoskeletal, gastrointestinal, haematological, respiratory, and psychotropic agents.

Pathogenetic mechanisms of vitiligo in a patient with Sézary syndrome

Patients exhibiting association between vitiligo and cutaneous T-cell lymphoma (CTCL) remain rare and it is not known whether some T-cell subpopulations of CTCL in the skin are able to recognize specific melanocytic epitopes and thus induce vitiligo. The aim of our study was to determine whether T cells specific to melanocyte differentiation antigens were detectable among tumour-infiltrating lymphocytes (TIL) in the hypopigmented skin of a patient with Sézary syndrome (SS). A 71-year-old patient presented with SS and developed vitiligo during the course of her disease. Immunohistochemical studies showed staining with HMB45 and MelanA antibodies in the pigmented skin biopsy, whereas no staining was observed in the hypopigmented skin biopsy. To analyse responses to melanocyte differentiation antigens, we used a transient COS transfection assay that permits an estimation of CD8 T-cell responses against a large number of HLA/antigen combinations. This technique allowed the detection of melanocyte differentiation antigen-specific T lymphocytes, directed mainly against Melan-A/MART1 antigen in the HLA-A*23 context. Our study supports the concept that vitiligo that has developed during the evolution of a CTCL is related to the presence of a T-lymphocyte subpopulation reactive against melanocyte differentiation antigens (mainly Melan-A/MART1) present in skin lesions. The role of interferon in the induction of this T-lymphocyte subpopulation is discussed.

Current management strategies for cutaneous T-cell lymphoma

Cutaneous T-Cell Lymphoma is a group of lymphomas characterized by a malignant proliferation of skin homing T cells. Prognosis is generally good and treatment is based on the stage of the disease with the goal of inducing remission. Patients with disease limited to the skin in the form of patches and plaques respond best to "skin directed therapy" with topical agents including corticosteroids, nitrogen mustard, carmustine, bexarotene gel, as well as phototherapy with ultraviolet B light, PUVA, or photodynamic therapy. Tazarotene and imiquimod show potential in the treatment of early CTCL. Patients with disease resistant to treatment or with advanced disease require more aggressive therapy in the form of total skin electron beam radiation, biologic response modifiers including interferon alpha, bexarotene, denileukin diftitox, extracorporeal photochemotherapy or combination therapy. The use of chemotherapy is used primarily for palliation. Allogeneic hematopoetic stem cell transplantation may represent a successful treatment for treatment resistant disease.

Phototherapy for cutaneous T-cell lymphoma

Phototherapy has been utilized for decades in the treatment of various dermatologic conditions, including cutaneous T-cell lymphoma (CTCL). Currently, a number of light sources are available, and selection of the specific modality is based on a number of factors, the most important of which is disease stage. The efficacy of broadband ultraviolet B (UVB) is limited to the patch stage, while psoralen and ultraviolet A (PUVA) is capable of clearing plaques and, sometimes, early tumors. Narrowband UVB is also effective for early stages and has practical advantages over PUVA, but more studies are needed to more fully evaluate its role in CTCL. Long-wave ultraviolet A (UVA1) has likewise shown efficacy, supported by findings of apoptosis induction in UVA1-treated cells. Long-term remissions have been reported for PUVA, but in the majority of cases, maintenance therapy was necessary. Although beneficial as monotherapy for early stages of the disease, phototherapy is also a useful adjunct to other modalities such as interferons, retinoids and electron beam therapy. Studies are ongoing to refine protocols for combination therapy, with the goal of improving efficacy, while minimizing adverse effects.

Leukoderma associated with Sézary syndrome: a rare presentation

We describe a patient with Sézary syndrome who was initially seen with the rare occurrence of both generalized erythroderma and extensive leukoderma of his lower limbs. Apart from the absence of melanocytes in the leukodermic skin, histopathologic features of both areas were identical, showing an infiltrate of atypical lymphocytes with epidermotropism. This form of Sézary syndrome-associated leukoderma is clinically distinguishable from hypopigmented mycosis fungoides in which hypopigmented lesions are the sole manifestation of the cutaneous T-cell lymphoma.

Vitiligo-like leucoderma during photochemotherapy for mycosis fungoides

We describe four patients with mycosis fungoides (MF) in whom depigmentation, and also leucotrichia in one, occurred following the resolution of the eruption during phototherapy (psoralen plus ultraviolet A treatment in three patients, climatotherapy in one). In all cases, the depigmentation was localized to the area of the pre-existing MF lesions. There was no clinically obvious phototoxicity. Biopsy study including S100 staining in all cases, and electron microscopy in one case, demonstrated the total absence of melanocytes, with no evidence of MF. It is suggested that the phototherapy may have activated a cell-mediated immunity leading to destruction of the melanocytes. We recommend that vitiligo-like leucoderma be added to the list of untoward effects of phototherapy in MF.

Leucoderma associated with flares of erythrodermic cutaneous T-cell lymphomas: four cases. The French Study Group of Cutaneous Lymphomas

We describe four patients with erythrodermic cutaneous T-cell lymphomas (two with erythrodermic mycosis fungoides, and two with Sézary syndrome) who presented with extensive hypopigmented lesions that occurred during flares of their cutaneous disease. These cases must be distinguished from previously described hypopigmented mycosis fungoides where hypopigmented lesions were the sole manifestation of the lymphoma. In two cases a biopsy was performed on hypopigmented skin, showing an infiltrate of atypical lymphocytes with epidermotropism and absence of melanocytes, as in vitiligo. It is suggested that the hypopigmentation could be due to the cytotoxicity of tumour or reactional lymphocytes directed against melanocytes.

Suplatast tosilate (IPD), a new immunoregulator, is effective in vitiligo treatment

The major type of vitiligo is considered to be an autoimmune disorder. Anti-melanocyte antibodies are frequently detected in sera of patients with this disease. Interleukin (IL)-4 released from Th2 cells is an important factor in stimulating autoantibody production by B-cells. In this study, seven patients with vitiligo treated with suplatast tosilate (IPD), three showed repigmentation and improvement of their lesions after administration of the drug. IPD halted the continuous spread of the lesions in three of the other patients, and, in two of them, also reduced microsome test and thyroid test titers. The efficacy of IPD in treating vitiligo was thought to be due to the suppressive effect of this drug on IL-4 production. No side effect was observed. Thus IPD may represent a new alternative in vitiligo treatment due to its inhibition of autoimmunity by the suppression of IL-4.

Treatment of vitiligo with oral 5-methoxypsoralen

Thirty-six patients with vitiligo were treated with oral 5-methoxypsoralen (5-MOP) and subsequently exposed to UVA irradiation. The patients were treated once or twice weekly over a period of 2-10 months, taking 40-60 mg of 5-MOP 2 hours before exposure to UVA light. The amount of exposure to UVA light was slowly increased according to the patient's tolerance. Eleven (31%) patients showed remarkable repigmentation of the areas of vitiligo within six months. Overall, 78% of the patients showed effective repigmentation. Areas of vitiligo on the face and trunk were more responsive to treatment than those on the distal part of limbs. Adverse effects due to the drug included 2 patients with nausea and 1 patient with headache. It is suggested that treatment with systemic 5-MOP is effective, safe, and useful in selected cases of vitiligo.

Leukoderma punctata

Thirteen patients with vitiligo (1 segmental, 4 focal, 8 generalized) aged 7 to 38, most of them female children, developed numerous punctate hypopigmented and achromic spots. The spots measured 0.5 to 1.5 mm and were located primarily on the sun-exposed areas of the extremities; they appeared following treatment with PUVASOL. Two of these patients experienced a reduction of this leukodermic defect, whereas the remaining patients showed a stable clinical course. Dopa and Fontana stains disclosed, in most cases, decreased but not absent functional melanocytes and a marked reduction of melanin. Ultrastructural studies demonstrated slight to severe damage of keratinocytes and melanocytes similar to that previously reported in vitiligo patients. The phototoxic effect of PUVASOL therapy is suggested as a possible etiologic factor in these patients. A probable relationship among idiopathic guttate hypomelanosis, leukoderma punctata, and vitiligo is discussed.

Psoralen photochemotherapy

Psoralens and sunlight have been used by the Egyptians and Indians for hundreds of years for the treatment of vitiligo. The combination of oral psoralens and artificial ultraviolet A (PUVA) therapy was approved for the management of severe psoriasis by the Food and Drug Administration in 1982. Since then PUVA therapy has been found to be an effective modality in the treatment of many cutaneous conditions. When properly administered, the major short-term side effects are minimal. The long-term side effects may include an increased risk of squamous cell carcinoma, atypical cutaneous pigmentation, accelerated skin aging, and ophthalmologic abnormalities. By careful patient selection and limiting the cumulative UVA dosage and frequency by using combinations or alternative therapies, these side effects may be reduced. Continued reporting of carefully carried out long-term prospective studies will provide us with more knowledge of the long-term side effects of PUVA. In the meantime, for each patient on PUVA therapy the risk/benefit ratio should be carefully considered.

Generalized vitiligo following Sézary syndrome

A patient with Sézary syndrome is reported in whom generalized vitiligo occurred. This is, to our knowledge, the first patient reported with vitiligo following T cell cutaneous lymphoma.

On the pathogenesis of idiopathic guttate hypomelanosis

Idiopathic guttate hypomelanosis is a common leukodermic dermatosis of obscure origin, consisting of small 2- to 5-mm achromic or hypopigmented macules, mainly affecting the exposed upper and lower extremities. In a group of 400 consecutive dermatologic patients, idiopathic guttate hypomelanosis was much more prevalent in women than in men. However, in both sexes this prevalence became more common with advancing age. In another group of fifteen patients with idiopathic guttate hypomelanosis and fifteen normal controls matched by age, sex, and skin type, the following was found: A cause-effect relationship between chronic actinic exposure and the development of idiopathic guttate hypomelanosis could not be established by statistical studies. A family aggregation survey disclosed a higher prevalence of idiopathic guttate hypomelanosis in the family of patients with idiopathic guttate hypomelanosis than in the control group. Epithelial atrophy, patchy absence of melanocytes and melanin, flattening of the rete pegs, and basket weave hyperkeratosis were the most prominent histologic findings of idiopathic guttate hypomelanosis. Minigrafts of normal skin implanted in idiopathic guttate hypomelanosis lesions did not modify the achromic defects, whereas intralesional triamcinolone with or without grafts improved the appearance of these lesions.

PUVA-induced melanocytic atypia: is it confined to PUVA lentigines?

Widespread lentigines in fourteen patients following long-term therapy with psoralens and ultraviolet A (PUVA) for psoriasis were documented by biopsy of a representative lesion in a non-sun-exposed site. Chronically PUVA-exposed nonlesional skin was examined in ten of the fourteen patients. Melanocytic atypia consisting of large or angular hyperchromatic nuclei was observed in 57% of PUVA lentigines and 70% of the nonlesional PUVA-exposed skin. Comparison with twenty-four specimens of lentigo simplex or solar lentigines revealed melanocytic nuclear atypia in only two cases. Binucleated melanocytes suggesting disturbed cellular kinetics were seen in all types of lesions examined but most commonly in PUVA lentigines. The presence of giant melanosomes was also a frequent nonspecific finding. Our findings of melanocytic atypia in chronically PUVA-exposed skin, as well as in PUVA lentigines, suggest that both sites are at risk for potential complications of repeated melanocytic stimulation. Whether melanocytic atypia will prove to be a precursor of melanocytic dysplasia or malignancy following PUVA therapy requires long-term evaluation.