T-cell receptor-gamma gene analysis in evolving to advancing cutaneous T-cell lymphoma

The diagnosis of cutaneous T-cell lymphoma is often a challenge for the dermatopathologist. Early stages can mimic inflammatory dermatoses. Our aim was to explore the applicability of a standard T-cell receptor-gamma polymerase chain reaction in various subtypes of cutaneous T-cell lymphomas. Ninety-six biopsy specimens from 38 patients were selected. These included 72 specimens of mycosis fungoides, 12 specimens of non-mycosis fungoides T-cell lymphomas, and 12 specimens in which histology was non-specific or equivocal in patients who were later diagnosed to have lymphoma. T-cell clones were detected in 53 of 72 specimens of mycosis fungoides and eight of 12 specimens of non-mycosis fungoides lymphomas. Of the 72 specimens of mycosis fungoides, T-cell clones were detected in eight of 10 specimens of mycosis fungoides-associated follicular mucinosis and pigmented purpura-like mycosis fungoides. Four specimens from the 12 prediagnostic for cutaneous T-cell lymphomas showed presence of T-cell clones, identical to subsequent clones detected when lymphoma was fully established. In specimens where histology is not diagnostic and T-cell receptor-gamma gene analysis is positive, patients should be followed up closely. T-cell receptor-gamma gene analysis is a useful adjunct to histological diagnosis of early stage and variant types of mycosis fungoides.     

Characterization of skin infiltrating cells in adult T-cell leukaemia/lymphoma (ATLL): clinical, histological and immunohistochemical studies on eight cases

Eight cases of adult T-cell leukaemia/lymphoma (ATLL) with cutaneous involvement were studied. The clinical and histological features of these cases were recorded and immunohistochemistry carried out using a panel of monoclonal antibodies to T-cell differentiation antigens. Patients with ATLL showed distinct differences from patients with mycosis fungoides (MF) and Sézary syndrome (SS). Patients tended to have papulonodular and purpuric skin eruptions with pleomorphic lymphoid infiltrates, and often a degree of vasculitis. There was a high level of expression of activated T-cell antigens, CD25, CD30, CD38, T9 and Leu 8.     

The expression of the Hodgkin's disease-associated antigen Ki-1 in cutaneous infiltrates

Reactivity for Ki-1 antibody was studied in 145 patients with a large variety of cutaneous disorders. The antigen was consistently expressed and by a high proportion of tumour cells in infiltrates in which atypical cells revealed a 'histiocytic' appearance, i.e. lymphomatoid papulosis (LP), T-immunoblastic lymphoma with the characteristic of true histiocytic lymphoma, Hodgkin's disease, T-blast cell proliferation with giant multivesicular bodies, concurrent LP and mycosis fungoides (MF), and two cases of MF. Ki-1+ cells with the usual morphology of atypical T-cells formed a major component in 2 other cases of MF, and a minor component in 7 other cases of MF. A possible non-neoplastic counterpart was found in small to medium-sized Ki-1+ cells, including blast cells, which occurred occasionally in the T-cell infiltrates of eczema, actinic reticuloid, lichen planus and pityriasis lichenoides. Small Ki-1+ cells which were observed in the reactive B/T cell component of lymphocytoma cutis but also in similar components occurring occasionally in non-epidermotropic cutaneous T-cell lymphoma, and malignant B-cell lymphomas, might be analogous to the Ki-1+ cells in normal lymphoid tissue.     

T-cell receptor variable region gene expression in cutaneous T-cell lymphomas

The cutaneus T-cell lymphomas (CTCL) arc a group of diseases characterized by malignant proliferations of CD4 positive T-cells having monoclonally rearranged T-cell receptor (TCR) genes. A recent study using monoclonal antibodies to two TCR β-chain variable (V) region gene products showed preferential expression of the Vβ8 gene product in these tumors. The finding of predominant usage of a single Vβ gene would imply that selection by antigen is important in the etiology of these tumors. We have studied eight cases of cutaneous T-cell lymphoma and one cell line derived from a patient with mycosis fungoides/Sezary syndrome, using an extended panel of antibodies to V region gene products. Contrary to the previous report, in our study expression of the Vβ8 gene product by tumor cells was not observed in any of the cases of CTCL or in the tumor cell line studied; preferential use of any of the variable region genes recognized by the antibodies in the panel was not observed.     

Genotypic analysis of cutaneous T-cell lymphomas

The gene encoding the beta-chain of the T-cell antigen receptor (TCR) has been analyzed for evidence of rearrangement in skin, blood, and lymph node specimens from 23 cases of known or suspected cutaneous T-cell lymphoma (CTCL). Two cutaneous large cell lymphomas, 4 cases of Sézary syndrome, and 5 cases of advanced (tumor) stages of mycosis fungoides showed clonal rearrangement of the TCR beta-chain gene in all samples, including lymph nodes in which histologic examination revealed only dermatopathic lymphadenitis. These results indicate that DNA analysis provides a valuable means for improving the diagnosis of extracutaneous disease in advanced stages of CTCL. In contrast, the gene was in a germline configuration in all samples from 12 patients with plaque stages of mycosis fungoides or suspected early CTCL, suggesting that in these 2 conditions the T-cell proliferation is either polyclonal or contains very few monoclonal (i.e., neoplastic) cells.     

Expression of bcl-2 protein and Ki-67 nuclear proliferation antigen in benign and malignant cutaneous T-cell infiltrates

The bcl-2 protein prolongs cell life by inhibiting apoptosis. Its expression has been studied in a variety of normal tissues and lymphomas but there is minimal information available concerning bcl-2 expression by benign and malignant cutaneous T-cells. Therefore, we investigated bcl-2 expression in a wide variety of cutaneous T-cell infiltrates using one- and two-color immunohistologic techniques, bcl-2 was expressed by the majority of lesional CD3⁺ T-cells in most cases. This included 22Departments of 26 cases of mycosis fungoides (MF), 3/3 cases of non-MF cutaneous T-cell lymphoma, 5/5 cases of lymphomatoid papulosis, 4/4 cases of T-cell rich cutaneous lymphoid hyperplasia, 2/3 cases of bullous pemphigoid, 2/2 cases of discoid lupus erythematosus and 1/1 case of lichen planus. Titration experiments and comparative studies of tonsil section positive controls revealed that, relative to mantle zone B-cells, there was over- expression of bcl-2 by a variable subset of T-cells in most cases. Assessment of multiple biopsies in a subset of MF cases showed stable expression of bcl-2 over intervals of up to two years. In contrast to the widespread expression of bcl-2 in both early and advanced MF skin lesions, abundant expression of the nuclear proliferation antigen, Ki-67, was skewed toward advanced MF skin lesions. Ten percnt or more Ki-67⁺ cells were present in 5% of patients with patches/thin plaques, 38% with moderate plaques, 64% with thick plaques and 100% with tumor nodules. Two-color immunohistologic analysis combined with molecular biologic analysis of clonality in the cases of T-cell rich cutaneous lymphoid hyperplasia indicated that bcl-2 expression was both a polyclonal and multi-lineage phenomenon, suggesting that it occurred by a physiologic rather than mutational mechanism. We conclude that bcl-2 expression is a common feature of cutaneous T-cell infiltrates that has minimal differential diagnostic value for distinguishing lymphomas from reactive T-cell infiltrates. In early MF lesions, abundant expression of bcl-2 and sparse expression of Ki-67 suggested that the accumulation of tumor cells during the initial progression of MF may be facilitated by prolonged clonal survival in conjunction with low-grade clonal proliferation.     

Treatment of cutaneous T-cell lymphomas with TP-5. Evaluation of the clinical effect in 8 patients

Eight patients with cutaneous T-cell lymphomas (6 patients with mycosis fungoides, 1 patient with Sézary's syndrome, 1 patient with low-grade malignant lymphoma, unclassified) were treated with TP-5, a synthetic pentapeptide having the same biologic activity as the thymic hormone thymopoietin. TP-5 was administered three times weekly at a dosage of 50 mg subcutaneously in 6 patients, 50 mg intravenously in 1 patient, and 100 mg subcutaneously in 1 patient. Clinical evaluation at the end of the trial disclosed improvement in 4 patients (2 patients with mycosis fungoides, 1 patient with Sézary's syndrome, 1 patient with low-grade malignant lymphoma, unclassified), deterioration in 3 patients with mycosis fungoides and no change in 1 patient with mycosis fungoides. As TP-5 evidently exerts some effect on cutaneous T-cell lymphomas, further investigations of its therapeutic potential in this group of diseases seem worthwhile.     

Lymphomas.

The diagnosis of lymphoma currently relies on a combination of clinical, routine histopathologic, and immunohistochemical studies, sometimes supplemented by other special techniques such as flow cytometry, DNA analysis, and gene rearrangement study. This review considers the practical diagnosis of cutaneous lymphoma, with particular emphasis on three areas: Hodgkin's disease, non-Hodgkin's lymphomas and their differentiation from lymphocytoma cutis, and mycosis fungoides and other T-cell lymphomas.     

The spectrum of cutaneous lymphomas in patients less than 20 years of age

Cutaneous lymphomas are rare in young patients and are mostly represented by mycosis fungoides and its variants and CD30+ lymphoproliferative disorders (lymphomatoid papulosis [LYP] and anaplastic large T-cell lymphoma). We report our observations in a series of 69 patients less than 20 years of age who presented either with primary cutaneous lymphoma (n = 62) or with secondary manifestations of extracutaneous disease (n = 7). Clinicopathologic features permitted classification of the cases into the following diagnostic categories: mycosis fungoides (n = 24, all primary cutaneous), anaplastic large T-cell lymphoma (n = 13, all primary cutaneous), LYP (n = 11, all primary cutaneous), subcutaneous "panniculitis-like" T-cell lymphoma (n = 1, primary cutaneous), small-medium pleomorphic T-cell lymphoma (n = 2, all primary cutaneous), natural killer (NK)/T-cell lymphoma, nasal-type (n = 1, secondary cutaneous), follicle center cell lymphoma (n = 1, primary cutaneous), marginal zone B-cell lymphoma (n = 7, all primary cutaneous), B-lymphoblastic lymphomas (n = 6, 3 primary and 3 secondary cutaneous), specific cutaneous manifestations of Hodgkin disease (n = 1, secondary cutaneous), and acute myeloid leukemia (n = 2, both secondary cutaneous). Cutaneous lymphoma in children should be differentiated from benign skin disorders that may simulate them. In particular, mycosis fungoides and LYP in this age group may present with clinicopathologic features reminiscent of inflammatory disorders such as pityriasis alba, vitiligo, pityriasis rosea, and pityriasis lichenoides et varioliformis acuta. Even in secondary cutaneous lymphomas, skin manifestations may be the first sign of the systemic disease, and a diagnosis may be achieved on examination of histopathologic specimens of a cutaneous lesion. Our study illustrates the wide spectrum of cutaneous lymphomas and leukemias in patients less than 20 years of age and underlines the need for proper interpretation of these lesions by dermatologists and dermatopathologists.     

Immunophenotyping of cutaneous lymphoid infiltrates in frozen and paraffin-embedded tissue sections: a comparative study

A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections was compared with a panel of antibodies reactive in frozen sections for the immunophenotyping of cutaneous lymphoproliferative disorders. Three T cell-associated markers (UCHL1, MT-1, MT-2, six B cell-associated markers (MB-1, MB-2, LN-1, LN-2, L-26, 4KB5), immunoglobulin heavy and light chains, anti-LCA antibody, two markers for Reed-Sternberg cells (Ber-H2, Leu-M1), one marker for macrophages (Mac-387) and anti-S-100 protein antibody were tested on normal skin, inflammatory skin diseases, and cutaneous lymphomas and pseudolymphomas. On the basis of the results in frozen sections, 12 inflammatory T cell diseases, 14 T cell lymphomas and pseudolymphomas, and 10 B cell lymphomas and pseudolymphomas were identified. In addition, two cases of specific skin infiltrates of Hodgkin's disease have been examined. Among T cell markers, the greatest sensitivity was exhibited by UCHL1, which stained all but one specimen of T cell infiltrate; it was negative in one specimen of mycosis fungoides that progressed into a T-immunoblastic lymphoma. The combined use of MB-2, LN-2, and 4KB5 identified all B cell proliferations. LN-1 marked germinal centers in all cases of follicular lymphoma and pseudolymphoma. Ber-H2 stained the Reed-Sternberg cells in both cases of Hodgkin's disease and the large cells in the histiocytic type of lymphomatoid papulosis. Mac-387 and anti-S-100 protein antibody recognized macrophages and T-zone histiocytes (Langerhans cells and interdigitating cells), respectively. A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections is proposed that facilitates the identification of most B and T cell infiltrates in the skin.     

Coexistence of CD30-positive anaplastic large cell lymphoma and mycosis fungoides

Primary cutaneous T-cell lymphomas, including lymphomatoid papulosis, mycosis fungoides and CD30+ anaplastic large cell lymphoma (ALCL) overlap clinicopathologically and form part of a spectrum of lymphoproliferative disorders. There have been several case reports of these diseases coexisting. We describe a 59-year-old Korean man who presented with a recurrent, solitary CD30+ ALCL of 25 years' duration as well as patch stage mycosis fungoides of 11 years' duration. Such occurrences may represent different clinical manifestations of the same clonal T-cell abnormality, and provide further insight into the pathogenesis of these related disorders.     

Adult T-Cell Leukemia/Lymphoma and Cutaneous T-Cell Lymphoma Are They Related?

Comparative studies were performed on clinical and laboratory features of four patients with different types of T-cell lymphoma of the skin; adult T-cell leukemia/lymphoma (ATLL), Sézary syndrome, mycosis fungoides, and Ki-1-positive lymphoma. All neoplastic cells studied showed a helper-inducer T-cell phenotype. A Ki-1-positive lymphoma is distinct from other types of cutaneous lymphomas because of unique morphologic and phenotypic features. Clonal proliferation of lymphocytes infected by human T-cell lymphotrophic virus (HTLV)-1 distinguishes ATLL from other T-cell lymphomas of the skin, especially in the endemic area of ATLL. From the pathogenic point of view, ATLL should not be included in a group with mycosis fungoides and Sézary syndrome.     

Mycosis fungoides and chronic lymphocytic leukaemia--composite T-cell and B-cell lymphomas presenting in the skin

Composite lymphomas involving cutaneous B-cell and T-cell lymphomas are very uncommon. We report here the unique circumstance of a patient with mycosis fungoides (primary cutaneous T-cell lymphoma) who later developed chronic lymphocytic leukaemia (B-cell lymphoproliferation, B-CLL), which presented in the skin (leukaemia cutis) as a composite lymphoma affecting an earlobe. The presence of both lymphoproliferative disorders was confirmed with immunophenotyping and the finding of both immunoglobulin gene rearrangements and T-cell receptor gene rearrangements in the ear and the same T-cell receptor gene rearrangement in a plaque lesion of mycosis fungoides on the arm.     

Cutaneous lymphomas other than mycosis fungoides in Singapore: a clinicopathological analysis using recent classification systems

BACKGROUND: Cutaneous lymphomas other than mycosis fungoides (MF) are a heterogeneous group with wide variations in clinical presentation, biological behaviour and prognosis. New classification systems have been designed or proposed in recent years, with well-defined disease entities and emphasis on the importance of site. OBJECTIVES: This study aims to analyse a series of non-MF lymphomas in an institution-based dermatological setting in Singapore, based on the European Organization for Research and Treatment of Cancer (EORTC) classification and the World Health Organization (WHO) classification. A secondary objective is to highlight the clinical utility of both classification systems. PATIENTS AND METHODS: Forty cases diagnosed over a 12-year period were examined by immunohistochemistry with antibodies targeting CD3, CD4, CD5, CD8, CD20, CD30, CD43, CD45RO, CD56 and CD68 in paraffin-embedded specimens. The immunohistological diagnosis was correlated with the clinical presentation and staging investigations for the final diagnosis and the course of disease recorded. RESULTS: Non-MF T-cell lymphomas presenting in the skin comprised 31 cases (78%) and were 3(1/2) times more common than B-cell lymphomas, which comprised nine cases (22%). The common subtypes were lymphomatoid papulosis, CD30+ large cell cutaneous T-cell lymphoma and subcutaneous panniculitis-like T-cell lymphoma. The commonly ascribed B-cell pattern with infiltrates in the mid and deep dermis and perivascular spaces was seen in 60% of T-cell lymphomas. Overall, there were equal numbers of primary cutaneous T-cell lymphomas and those due to concurrent or secondary cutaneous lymphoma. Five of six cases of subcutaneous panniculitis-like T-cell lymphoma had concurrent cutaneous and systemic involvement and their median survival was 7 months. CONCLUSIONS: The predominance of cutaneous T-cell lymphomas in this case series closely matched that reported from east Asia; cutaneous B-cell lymphomas are much less common than in Europe. The EORTC classification, which is designed only for primary cutaneous lymphomas, should be used in conjunction with the WHO classification because of the high prevalence of cutaneous lymphomas as the secondary site of disease from systemic lymphoma. In addition, subcutaneous panniculitis-like T-cell lymphoma is a primary cutaneous lymphoma where systemic involvement is common at initial presentation. We propose full immunophenotyping and complete clinical evaluation with staging investigations for all patients presenting with cutaneous lymphomas other than MF.     

An ultrastructural morphometric and immunohistochemical analysis of cutaneous lymphomas and benign lymphocytic infiltrates of skin. Useful criteria for diagnosis

Our combined ultrastructural, immunohistochemical, histologic, and clinical studies over the past five years have allowed us to compile diagnostic criteria useful in the evaluation of cutaneous lymphomas. As a group, mycosis fungoides (MF) patients could be distinguished from those with benign disorders of skin using ultrastructural morphometry (mean form factor and perimeter values), but with some overlap between groups. Another approach, the ultrastructural histogram method, however, clearly separated MF patients from patients with chronic dermatitis. Immunohistochemistry was useful in distinguishing cases of cutaneous peripheral T-cell lymphoma from MF cases on the basis of the occurrence of "novel phenotypes." Neoplastic T-cell infiltrates of skin can usually be distinguished from benign polyclonal T-cell infiltrates by the presence of one T-cell subset to the exclusion of others. Patients with convoluted B-cell lymphomas could also be distinguished from MF patients using ultrastructural morphometric dual parameter analysis. The diagnostic complexity of several cutaneous T-cell lymphoma cases is illustrated. We have emphasized in this study the strength of combining quantitative electron microscopy, immunohistochemistry, and histology in the diagnostic workup of cutaneous lymphomas. This integrative approach may be necessary to assure a definitive diagnosis in difficult cases.     

Demonstration of clonal disease in early mycosis fungoides.

Cutaneous T-cell lymphomas (CTCLs) are known to show monoclonal T-cell infiltrates late in the course of the disease. However, detection of monoclonal T-cell proliferation in early stages is difficult. To investigate the possibility that clones might appear only as minor subpopulations, we analyzed the proliferative activity of T cells expression certain variable (V) regions of the T-cell receptor (TCR). In biopsy specimens from 27 patients with CTCLs, all T cells expressing the V regions V alpha 2, V beta 5a, V beta 5b, V beta 6, V beta 8 and V beta 12 accounted for less than 5% of the total infiltrate. In the vast majority of the cases, less than 3% of the cells expression one TCR V region proliferated. In one case of mycosis fungoides, however, an epidermotropic clone expressing V beta 8 was detected. This clone was present in two distinct lesions from different anatomic sites and was found in an early relapse 1 year after complete remission following PUVA therapy. The case described here documents the possibility of clonal disease early in the course of mycosis fungoides.     

Granulomatous slack skin: a distinct disorder or a variant of mycosis fungoides?

About 75% of cutaneous lymphomas belong to the group of T-cell lymphomas. Mycosis fungoides is the most common entity in this group. Granulomatous slack skin is a rare form of cutaneous T-cell lymphoma closely related to mycosis fungoides. We present here a patient with areas of lax skin for several years who developed a generalized erythroderma with associated immunoactivation and a deterioration in his general condition. This report discusses clinically and histologically the differential diagnoses, namely granulomatous slack skin and granulomatous mycosis fungoides, and suggests that these 2 disorders are only variants in the broad spectrum of a single disease.     

Non-Hodgkin lymphoma of the skin excluding mycosis fungoides and cutaneous involvement of adult T-cell leukemia/lymphoma*

Forty-nine cases of cutaneous malignant lymphoma were reviewed in order to analyze the clinicopathological features of these neoplasms. Excluding 13 cases of mycosis fungoides and 4 cases of cutaneous involvement of proven adult T-cell lymphoma/leukemia, the remaining 32 cases were further classified according to their pathological and clinical features. There were 12 primary cutaneous lymphomas, 15 cases of secondary cutaneous involvement of systemic lymphoma, and 5 cases of concurrent skin and lymph node involvement. Histologically, large cell lymphoma predominated in both primary and secondary cutaneous lymphomas. Immunohistochemical study using monoclonal antibodies reactive with B- and T-cells in paraffin sections revealed the cellular lineage in 30 cases. Nineteen cases were of T-cell origin and 11 cases were of B-cell derivation. The prognosis of these patients was rather poor; 25 patients died within 5 years. The predominance of T-cell lymphoma contrasts with a higher frequency of cutaneous B-cell lymphoma in Western countries. As the clinicopathological features of cutaneous lymphomas are diverse, it is suggested that cutaneous lymphomas should be classified and studied in a similar way to their nodal counterparts.     

Kutane Lymphome

Cutaneous lymphomas are a heterogeneous group of clonal proliferations of T and B lymphocytes with various clinical manifestations and prognosis. The new EORTC WHO classification of cutaneous T- and B-cell lymphomas provides a uniform nomenclature based on clinical, histologic, cytologic and molecular biological features. Accurate classification is a prerequisite for uniform therapeutic concepts. For office-based dermatologist, more than 50% of the therapies deal with classic forms of cutaneous T-cell lymphomas, type mycosis fungoides. In recent years the paradigm for the therapy of cutaneous T-cell lymphomas has changed. Since early aggressive treatment with cytostatic agents does not increase the response rate or overall survival, a commonly accepted stage-adapted therapy is recommended. In this review the current status of the therapy of cutaneous lymphoma is described in detail.