Prognostic Significance of a Polymerase Chain Reaction–Detectable Dominant T-Lymphocyte Clone in Cutaneous Lesions of Patients With Mycosis Fungoides

The utility and limitations of B- and T-cell gene rearrangement studies in evaluating lymphoproliferative disorders

A hallmark of lymphoid malignancies is the presence of a monoclonal lymphocyte population. Monoclonality of B- and T-cell populations can be established through immunoglobulin (IG) or T-cell receptor (TCR) gene rearrangement analysis, respectively. The biological rationale of IG and TCR gene rearrangement analysis is that due to the extensive combinatorial repertoire made possible by V(D)J recombination in lymphocytes, it is unlikely that any substantive lymphocyte population would share the same IG or TCR gene rearrangement pattern unless there is an underlying neoplastic or reactive origin. Modern IG and TCR gene rearrangement analysis is typically performed by polymerase chain reaction (PCR) using commercially available primer sets followed by gel capillary electrophoresis. This process is highly sensitive in the detection of nearly all lymphoid malignancies. Several pitfalls and limitations, both biological and technical, apply to IG/TCR gene rearrangement analysis, but these can be minimised with high quality controls, performance of assays in duplicate, and adherence to strict criteria for interpreting and reporting results. Next generation sequencing (NGS) will likely replace PCR based methods of IG/TCR gene rearrangement analysis but is not yet widespread due to the absence of standardised protocols and multicentre validation.

CD30 expression and proliferative fraction in nontransformed mycosis fungoides

The major differential diagnosis for a primary cutaneous T-cell lymphoproliferative disorder with CD30 (Ki-1) positivity includes primary cutaneous anaplastic large cell lymphoma, lymphomatoid papulosis, pagetoid reticulosis and transformed mycosis fungoides (MF). Little is known, however, about CD30 expression in nontransformed MF, whether it simply reflects the proliferative fraction and if either CD30 staining or the proliferative fraction are of prognostic significance. Therefore, 47 nontransformed MF biopsies were stained for CD30 and Ki-67. The proportions of positive cells were determined and correlated with each other as well as with age, stage at diagnosis, maximum stage and survival. All cases had at least rare dermal CD30-positive cells. Higher percentages of dermal CD30 and Ki-67-positive cells were associated with a higher stage at diagnosis, and together with epidermal CD30, associated with a higher maximum stage. The proportion of CD30 and Ki-67-positive cells did not correlate with each other. Survivals were shorter if the dermal CD30 or epidermal or dermal Ki-67% were greater than the median (4.7%, 14%, 13%) and in patients of greater than or equal to 60 years of age or with a high stage. Dermal Ki-67 as a continuous variable was an independent prognostic indicator (P<0.001), as were dermal Ki-67 (P=0.004) and dermal CD30 (P=0.027) when analyzed as dichotomous variables but not stage. Therefore, CD30 expression is not restricted to transformed MF but higher levels of dermal CD30 expression and, even more so, dermal Ki-67 levels are independent adverse prognostic indicators.

Clinicopathological features and T-cell receptor gene rearrangement findings of mycosis fungoides in patients younger than age 20 years

Mycosis fungoides (MF) is the most common form of cutaneous T-cell lymphoma that usually arises in middle-aged or older people. The incidence of childhood MF is low, but studies in childhood MF suggests that the incidence is rising. The number of studies in childhood MF are few and there are currently no studies about childhood MF in Asians. We investigated the clinicopathological features, T-cell receptor (TCR) gene rearrangement findings, treatment and follow up in childhood MF. The retrospective study was performed on a population consisting of 23 MF patients aged 4-19 years. The duration of the disease ranged from 1 month to 10 years (mean, 2.7 years). In Tumor-Node-Metastasis classifications, all cases were confined to stage IA or IB. Histopathological findings revealed epidermotropism and perivascular infiltrates, epidermotropism in the infundibulum, Pautrier's microabscess, haloed lymphocytes, epidermal lymphocytes larger than dermal lymphocytes, atypical cells with hyperchromatic nuclei and wiry bundles of collagen. TCRgamma gene rearrangement was performed except for four patients, and monoclonality was detected in 16 of 19 cases (84%). Treatment was done with psoralen and ultraviolet (UV)A, UVA1, narrow-band UVB, topical steroid, retinoic acid and calcipotriol. Most patients showed a good response. At a mean follow up of 90.4 months, no patient had either an exacerbation of the disease or extracutaneous involvement. Compared with adult-onset MF, MF in children may show a variety of clinical features. It is considered to have a good prognosis. Moreover, histopathological study and TCR gene rearrangement study can help in the diagnosis of MF in children.

T-Cell Receptor-G Gene Rearrangement Analysis in the Diagnosis of Patients with Erythroderma / Dijagnostički Značaj Analize Preuređenja Gena Gama Lanca T-Ćelijskog Receptora Kod Pacijenata Sa Eritrodermijom

The diagnosis of erythroderma is challenging, since clinical, histopathological and immunophenotypic findings are insufficient to differentiate between inflammatory and lymphomatous erythroderma. Thus, multiplex PCR was used for T-cell receptor-γ gene rearrangement analysis, in the skin and peripheral blood samples of 24 patients (20 men and 4 women) with erythroderma of varying origin, in order to estimate its diagnostic value. Cutaneous T-cell lymphoma was confirmed in 9, benign inflammatory dermatosis in 12, and idiopathic erythroderma and clonal dermatitis in 3 patients. In the group of patients with erythrodermic cutaneous T-cell lymphoma, the dominant clone was detected in the skin of 8/9, and in none of the patients with inflammatory dermatoses. A dominant clone was found in peripheral blood of 5/6 samples of patients with erythrodermic cutaneous T-cell lymphoma, and in 2/12 patients with inflammatory dermatosis. T-cell receptor-γ gene rearrangement analysis is valuable in differentiation between inflammatory and lymphomatous erythroderma, thus substantially improving the diagnosis of patients with erythroderma.

Cutaneous Lymphomas

The skin is the most common site of extranodal non-Hodgkin lymphoma, with a yearly incidence approaching 1 per 100,000 individuals in the United States. Skin lymphomas are classified broadly into cutaneous T-cell lymphoma (CTCL) and cutaneous B-cell lymphoma (CBCL). Within these broad categories, multiple unique pathologic entities exist with a wide array of natural histories and treatment options. Radiotherapy plays an important role in the curative treatment of localized CTCL and CBCL and may be used to palliate cutaneous and visceral symptoms associated with advanced disease. This review highlights the role of radiotherapy in the multidisciplinary management of cutaneous lymphoma.

Molecular Analysis of T-Cell Receptor β Genes in Cutaneous T-Cell Lymphoma Reveals Jβ1 Bias

Molecular characterization of T-cell receptor junctional region sequences in cutaneous T-cell lymphoma had not been previously reported. We have examined in detail the features of the T-cell receptor beta (TCRB) gene rearrangements in 20 individuals with well-defined stages of cutaneous T-cell lymphoma (CTCL) comprising 10 cases with early-stage mycosis fungoides (MF) and 10 cases with late-stage MF or Sezary syndrome. Using BIOMED-2 PCR primers, we detected a high frequency of clonally rearranged TCR gamma and TCRB genes (17/20 and 15/20 cases, respectively). We carried out sequencing analysis of each complete clonal variable (V)beta-diversity (D)beta-joining(J)beta fingerprint generated by PCR amplification, and determined the primary structure of the Vbeta-Dbeta-Jbeta junctional regions. We observed considerable diversity in the T-cell receptor Vbeta gene usage and complementarity-determining region 3 loops. Although we found that TCRB gene usage in CTCL and normal individuals share common features, our analysis also revealed preferential usage of Jbeta1 genes in all cases with advanced stages of disease.

Clinicopathologic features and T-cell receptor gene rearrangement findings of mycosis fungoides palmaris et plantaris

BACKGROUND

Mycosis fungoides palmaris et plantaris (MFPP), characterized by hyperkeratotic patches or plaques confined to the palms and soles, is rare and easy to misdiagnose because of the clinical similarity to psoriasis, cutaneous inflammatory dermatoses, and dermatophytic infections. The literature about MFPP mostly consists of case reports with short-term follow-up.

OBJECTIVE

Our purpose was to evaluate the clinicopathologic features, T-cell receptor (TCR) gene rearrangement findings, and prognosis of MFPP.

PATIENTS AND METHODS

This retrospective study has been reviewed in the clinicopathologic, TCR gamma gene rearrangement findings and follow-up study of 12 patients with MFPP.

RESULTS

The duration of diseases ranged from 9 months to 25 years with a mean duration of 5.3 years. Clinically, hyperkeratotic patches and plaques were observed in all cases, with 6 cases having developed on the palms and soles and 6 cases on the palms only. In TNM classifications, all cases were confined to T1N0M0 (stage IA) showing an early stage of mycosis fungoides (MF). Histopathologic findings revealed marked hyperkeratosis, parakeratosis with plasma, epidermotropism, convoluted lymphocytes, haloed lymphocytes, dense infiltrate of lymphocytes in all 12 cases (100%), Pautrier's microabscess in 9 cases (75%), a wiry bundle of collagen in 11 cases (91.7%) and basilar epidermotropism in 3 cases (25%). TCR gamma gene rearrangement was performed except for one case and monoclonality was detected in 10 of 11 cases. In the comparison group with cutaneous inflammatory dermatoses, all cases showed polyclonality. Treatment was done with Re-PUVA (acitretin and PUVA), ultraviolet A1, as well as systemic acitretin and methotrexate. Most patients showed a good response. In the follow-up study of 9 cases for a mean period of 47.6 months, only one patient's skin lesions were extended to the trunk and face, but the other patients had no sign of extracutaneous involvement.

LIMITATIONS

These results were obtained from patients with MFPP in Korea. A cooperative study with other ethnic groups will be helpful.

CONCLUSIONS

If a patient has recalcitrant palmoplantar dermatosis, MFPP should be suspected and histopathologic studies with TCR gene rearrangement should be done for early diagnosis of MFPP.

Defining early mycosis fungoides

This editorial review summarizes the results of 5 meetings sponsored by the International Society for Cutaneous Lymphoma at which the clinicopathologic and ancillary features of early mycosis fungoides were critically examined. Based on this analysis, an algorithm was developed for the diagnosis of early mycosis fungoides involving a holistic integration of clinical, histopathologic, immunopathologic, and molecular biological characteristics. A novel aspect of this algorithm is that it relies on multiple types of criteria rather than just one, for example, histopathology. Before its finalization, the proposed diagnostic algorithm will require validation and possibly further refinement at multiple centers during the next several years. It is anticipated that a more standardized approach to the diagnosis of early mycosis fungoides will have a beneficial impact on the epidemiology, prognostication, treatment, and analysis of clinical trials pertaining to this most common type of cutaneous lymphoma.

Ichthyosiform mycosis fungoides: report of a case associated with IgA nephropathy

We report a case of ichthyosiform mycosis fungoides (MF) associated with IgA nephropathy. Histological examination showed a dense atypical lymphocytic infiltrate admixed with epithelioid cells and giant cells in the dermis associated with the features of epidermotropism and folliculotropism. Reported cases of ichthyosiform MF are reviewed and histopathological characters of ichthyosiform MF are summarized. We suggest a histiocyte/dendritic-cell-rich infiltrate, or granulomatous features of infiltrate may be another characteristic of ichthyosiform MF. This case was associated with IgA nephropathy, which is uncommon. Such a presentation has never been reported in the literature.

T-cell receptor γ gene rearrangement by multiplex polymerase chain reaction/heteroduplex analysis in patients with cutaneous T-cell lymphoma (mycosis fungoides/Sézary syndrome) and benign inflammatory disease: correlation with clinical, histological and i

BACKGROUND

A dominant T-cell clone can be detected by polymerase chain reaction (PCR) in 40-90% of cutaneous samples from patients with cutaneous T-cell lymphoma (CTCL).

MATERIALS AND METHODS

From 1996 to 2003 we analysed 547 cutaneous biopsies performed to exclude CTCL (mycosis fungoides, MF/Sézary syndrome, SS). The final diagnosis was benign inflammatory disease (BID) in 353 samples (64.5%) and CTCL in 194 (35.5%). T-cell receptor (TCR)-gamma gene rearrangement was studied by using a multiplex PCR/heteroduplex (HD) analysis. The PCR results were correlated with the clinical picture, the histological pattern and the presence of T-cell lineage antigen loss, using univariate and multivariate logistic regression analyses.

OBJECTIVE

To determine the sensitivity and specificity of the multiplex PCR/HD analysis and to identify which are the clinical, histopathological or immunophenotypical features significantly associated with a positive T-cell clonality.

RESULTS

A clonality was demonstrated in 83.5% of CTCL and in 2.3% of BID (P < 0.001). A significantly higher percentage of clonal cases was associated with the cutaneous T-score (71.4% in T1, 76.1% in T2 and 100% in nodular and erythrodermic MF samples) and with the presence of a T-cell lineage antigen loss (93.9% vs. 77.4%). Moreover, clonality was closely related to an increase in the histopathological score (51.3% in the samples with a score < 5, compared with 92% in the lesions with > or = 5). No significant difference in the percentage of clonal cases was found between T1/T2 and T3/T4 lesions with a histopathological score > or = 5. The multivariate logistic regression showed that the density and extent of the cell infiltrate, the degree of epidermotropism and the presence of cytological atypia share an independent predictive value for clonality in T1/T2 samples, even if the highest odds ratios (3.6) were associated with the density of the cell infiltrate. The disease course of T1/T2 patients was analysed according to the PCR findings. All the PCR-negative patients showed a long-standing stable disease course; on the other hand, a disease progression occurred in 12/87 (13.8%) positive patients.

CONCLUSIONS

The multiplex PCR/HD analysis is associated with a high diagnostic accuracy (92.7%) in CTCL patients. The finding of a clonal T-cell rearrangement is more closely associated with the histological pattern (in particular with the density and extent of the cell infiltrate) rather than with the MF cutaneous T-score or immunophenotype.

Long-term experience with low-dose interferon-alpha and PUVA in the management of early mycosis fungoides

OBJECTIVES

Combined high-dose Interferon-alpha and psoralen plus ultraviolet A irradiation (PUVA) have been reported to be effective in the treatment of early mycosis fungoides (MF); however, our study is the first controlled prospective study in the literature exploring the activity and tolerability of the combination with low dosages and evaluating further clinical outcome of early-MF patients.

METHODS

We carried out a multicentric prospective Phase II clinical study on 89 patients with early-stage IA to IIA MF treated for 14 months with low-dose IFN-alpha2b (6-18 MU/wk) and PUVA. Treatment success was analysed in terms of freedom from treatment failure.

RESULTS AND CONCLUSIONS

Complete remission (CR) was achieved in 84% and an overall response rate in 98% of cases: six-month CR was associated with a non-confluent skin infiltrate at histology (P = 0.044) and 14-month CR with high epidermal CD1a+ dendritic-cell density (P = 0.030). The combination protocol was successfully tolerated and the most common reason of 'failure' was related to relapse and not to toxicity. Sustained remissions were achieved in 20% of patients. High CD8+ lymphoid T-cell density was associated with a lower relapse rate (P = 0.002). We think that our combination therapy can be considered an alternative approach compared with other modalities. Good immunological host surveillance in the skin lesions seems to be an optimal basis for the therapeutic success.

Immunopathogenesis and therapy of cutaneous T cell lymphoma

Cutaneous T cell lymphomas (CTCLs) are a heterogenous group of lymphoproliferative disorders caused by clonally derived, skin-invasive T cells. Mycosis fungoides (MF) and Sezary syndrome (SS) are the most common types of CTCLs and are characterized by malignant CD4(+)/CLA(+)/CCR4(+) T cells that also lack the usual T cell surface markers CD7 and/or CD26. As MF/SS advances, the clonal dominance of the malignant cells results in the expression of predominantly Th2 cytokines, progressive immune dysregulation in patients, and further tumor cell growth. This review summarizes recent insights into the pathogenesis and immunobiology of MF/SS and how these have shaped current therapeutic approaches, in particular the growing emphasis on enhancement of host antitumor immune responses as the key to successful therapy.

Cellular coincidence of clonal T cell receptor rearrangements and complex clonal chromosomal aberrations-a hallmark of malignancy in cutaneous T cell lymphoma

Detection of a clonal T cell receptor (TCR) gene rearrangement is used in the diagnosis of primary cutaneous T cell lymphomas (CTCL) whereas chromosomal aberrations serve as a diagnostic tool for leukaemias and nodal lymphomas. To what extent both approaches specify the same cell population remains unknown. We investigated the coincidence of TCR clonality with complex clonal chromosomal aberrations, indicating qualitative alteration of the affected cells, in 17 CTCL patients. Out of 41 skin, blood, and lymph node samples studied, 34 gave results in chromosome and TCR analyses. With 88%, most specimens revealed corresponding results by both techniques (27 of 34 clonal, three of 34 non-clonal). In two patients, analysis of micro-dissected cells demonstrated that neoplastic T cells bear both a dominant TCR rearrangement and a complex chromosomal aberration. The cutaneous clone was found in blood samples of 11 of 12 patients (including early stages), and investigation of follow-up skin and blood samples indicated persistence of the T cell clone in 11 of 14 cases. In conclusion, we show that dominant TCR clones and chromosomal clones converge in all stages of CTCL. These clones disseminate into blood and skin at early disease stages and persist despite therapy. The coexistence of a dominant TCR clone and a clonal chromosomal aberration can thus be used as a hallmark of malignancy.

Fréquence des cancers associés dans les lymphomes cutanés

INTRODUCTION

The initial staging and follow-up of cutaneous lymphomas is far from being standardized. In this retrospective study, we describe the results of systematic laboratory investigations dedicated to a better definition of the TNM stage for the detection of associated malignancies.

PATIENTS AND METHODS

This was a retrospective, descriptive, single centre study, including all cases of cutaneous lymphomas seen in the department of dermatology, university hospital of Reims, between 1987 and 2001. Data systematically recorded for each patient included clinical, biological, histological and molecular (cutaneous or circulating T or B clone) findings, imaging (thoracic and abdominal computed tomography scan; or chest X-ray and abdominal ultrasound tomography) and bone marrow histology (for B-cell cutaneous lymphomas only).

RESULTS

In cutaneous T-cell lymphomas (n=63 including 47 mycosis fongoides), imaging revealed deep lymph nodes in 4 cases, a carcinoma of the kidney in one case, and a benign tumour in 6 cases. A T-cell clone was detected in the skin in 19/33 cases and in peripheral blood in 17/31 cases. In cutaneous B-cell lymphomas (n=23), imaging showed splenomegaly in 2 cases, a B-cell clone was detected in 3/12 cases in the skin, and bone marrow histology was normal in 21/22 cases. Among patients with cutaneous T-cell lymphomas, 14/63 (22 p. 100) had an associated malignancy. In 8/14 cases, the diagnosis of the associated malignancy was made prior to that of the cutaneous T-cell lymphoma. In 4 cases, the interval between the previous malignancy and the diagnosis of lymphoma was <or=2 Years, and in 2 other cases the malignancy was discovered on the occasion of the staging of the T-cell cutaneous lymphoma.

CONCLUSION

Laboratory investigations in cutaneous lymphomas are necessary to research deep lymph nodes, especially in case of high stage T-cell lymphomas. In exceptional cases they can reveal an associated malignancy, which is usually detected by clinical examination. In cutaneous B-cell lymphoma, bone marrow histology or cytology is generally normal hence may not be justified in low grade or localized cutaneous B-cell lymphomas.

Sezary Syndrome Cells Unlike Normal Circulating T Lymphocytes Fail to Migrate Following Engagement of NT1 Receptor

Circulating malignant Sezary cells are a clonal proliferation of CD4+CD45RO+ T lymphocytes primarily involving the skin. To study the biology of these malignant T lymphocytes, we tested their ability to migrate in chemotaxis assays. Previously, we had shown that the neuropeptide neurotensin (NT) binds to freshly isolated Sezary malignant cells and induces through NT1 receptors the cell migration of the cutaneous T cell lymphoma cell line Cou-L. Here, we report that peripheral blood Sezary cells as well as the Sezary cell line Pno fail to migrate in response to neurotensin although they are capable of migrating to the chemokine stromal-cell-derived factor 1 alpha. This is in contrast with normal circulating CD4+ or CD8+ lymphocytes, which respond to both types of chemoattractants except after ex vivo short-time anti-CD3 monoclonal antibody activation, which abrogates the neurotensin-induced lymphocyte migration. Furthermore, we demonstrate that neurotensin-responsive T lymphocytes express the functional NT1 receptor responsible for chemotaxis. In these cells, but not in Sezary cells, neurotensin induces recruitment of phosphatidylinositol-3 kinase, and redistribution of phosphorylated cytoplasmic tyrosine kinase focal adhesion kinase and filamentous actin. Taken together, these results, which show functional distinctions between normal circulating lymphocytes and Sezary syndrome cells, contribute to further understanding of the physiopathology of these atypical cells.

Diagnosis, staging, and monitoring of cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma includes mycosis fungoides and its leukemic variant, the Sézary syndrome. This review discusses the clinical, histopathologic, immunophenotypic and immunogenotypic features of cutaneous T-cell lymphoma as they apply to the diagnosis, staging and monitoring of this disease.

Peripheral blood T-cell clonality in mycosis fungoides and nonlymphoma controls

In mycosis fungoides (MF), T-cell clonality is reported in about 90% of skin and 40% of blood samples. However, identity of blood and cutaneous T-cell clone and prognostic relevance of blood T-cell clonality remain controversial. By PCR/fluorescence fragment analysis with estimation of clonal fragment lengths and relative peak heights, we objectively identified T-cell clonality unrelated to malignant lymphoproliferation in healthy donors (5/38), autoimmune dermatoses (3/8), and nonlymphoma skin cancer (9/39). This T-cell expansion of undetermined significance (TEXUS) was also found in 8/64 MF patients. Dissemination of neoplastic cells into blood, as identified by identical clonal fragment lengths in blood and skin, was detected in 23/64 MF patients. When monitoring for progression at TNM stage for a mean of 45.7 months, univariate analysis identified age of >60 years and detection of a related blood T-cell clone to be of prognostic relevance, whereas detection of TEXUS, sex, TNM stage at initial diagnosis, and detection of a cutaneous T-cell clone were irrelevant. Although multivariate analysis was not possible, further stratification clearly indicated an age of >60 years to be the predominating prognostic factor. In conclusion, investigation of T-cell clonality in skin and blood samples at the initial diagnosis cannot predict the clinical course of MF and the occurrence of TEXUS should be considered when assessing blood T-cell clonality.

Correlations between clinical, histologic, blood, and skin polymerase chain reaction outcome in patients treated for mycosis fungoides

Little information is currently available regarding post-treatment outcome of TCR-targeted PCR in skin and/or peripheral blood in patients with Mycosis Fungoides (MF) when a dominant gene rearrangement is present at time of diagnosis. To address this matter, a study evaluating the correlations between post-treatment clinical, histological, blood and skin PCR data was conducted in MF patients. Twenty-seven MF patients with dominant gene rearrangement in skin lesions at time of diagnosis were selected. Peripheral blood samples were investigated as well before treatment and post treatment molecular data in skin and blood were compared with clinical and histological outcome. A dominant gene rearrangement was detected before treatment in blood of 16/25 patients. The dominant gene rearrangement disappeared from cutaneous lesions in 8/13 patients displaying complete clinical and histological response whereas skin PCR remained positive in all 10 patients with histologically persistent disease. A dominant gene rearrangement was still present in blood in 10/16 patients after treatment and blood data were not correlated with skin molecular response. This study confirms frequent detection of a dominant gene rearrangement in peripheral blood in MF patients and shows that PCR may remain positive in lesional sites even when skin lesions are successfully treated.

Minimal residual disease in mycosis fungoides follow-up can be assessed by polymerase chain reaction

BACKGROUND

T-cell receptor (TCR) gene rearrangement analysis, i.e. T-cell clonality, using polymerase chain reaction (PCR) is a routine method used to assess the presence of a cutaneous dominant T-cell clone in mycosis fungoides (MF).

OBJECTIVES

To compare the outcome of cutaneous lesions of MF after treatment with the fate of the cutaneous T-cell clonality, and to determine whether minimal residual disease can be detected in patients in clinical complete remission.

METHODS

Fifty-one patients histologically diagnosed as having MF (17 stage IA, 21 stage IB and 13 stage III) were included in this retrospective study. T-cell clonality was analysed by GC-clamp multiplex PCRgamma-denaturing gradient gel electrophoresis. Every patient had two cutaneous biopsies at least 3 months apart. The second biopsy was performed at the site of a treated lesion.

RESULTS

The presence or absence of a dominant T-cell clone in the skin remained identical in 26 of the 31 (84%) patients with persistent disease. Thirteen patients with a detectable dominant T-cell clone at diagnosis went into complete clinical remission. In nine of these 13 (69%) patients, the T-cell clone was no longer detectable after treatment. The remaining four (31%) patients had an unchanged T-cell clonality.

CONCLUSIONS

The TCR gene rearrangement imprint is a stable and reliable tumour marker of MF disease. One-third of patients in complete clinical remission had a cutaneous molecular residual disease, the prognostic value of which will be analysed in an ongoing prospective study.

Isolation of a CD8alphaalpha+ CD4- tumour T-cell clone with cytotoxic activity from a CD4+ CD8- cutaneous T-cell lymphoma

BACKGROUND

We have previously established tumour T-cell lines, both from the skin and from the blood of patients with a cutaneous T-cell lymphoma (CTCL). In one patient, the tumour cells and the derived cell lines had a CD3+ CD4+ CD8- phenotype and a trisomy of chromosome 7. They expressed three T-cell receptor (TCR) beta-chain transcripts, but only one was productively rearranged and expressed at the cell membrane.

OBJECTIVES

In the present study, we tried to isolate a fast-growing new tumour T-cell line from the same patient.

PATIENTS/METHODS

We performed direct cell cloning of the skin tumour lymphocyte population, which led to the isolation of an interleukin-2-dependent highly proliferative T-cell subclone, named Cou-L3, with a CD3+ TCR-Vbeta13+ CD4- CD8alphaalpha+ phenotype.

RESULTS

We demonstrated that Cou-L3 was identical to the original clonal tumour CD3+ Vbeta13+ CD4+ CD8- cells, as it expressed the same rearranged TCR-Vbeta13 chain. We further studied the functional activity of these CD8alphaalpha+ Vbeta13+ Cou-L3 cells. We found that these cells exhibited CD3-redirected cytotoxic activity.

CONCLUSIONS

An immunophenotypic shift, with a change from a CD4+ to a CD8+ phenotype, has been already reported in association with disease progression in CTCL. However, in these cases, there has been no demonstration that the phenotypic change involved the same T-cell clone. The present study is the first report of the phenotypic heterogeneity of the tumour clonal cell population in CTCL.

Clonal heterogeneity in mycosis fungoides and its relationship to clinical course

Mycosis fungoides (MF) is a cutaneous T-cell lymphoma characterized by multifocal disease and protracted clinical course. The few studies that have assessed T-cell receptor (TCR) gene rearrangements (GRs) present at different anatomic sites in MF have generally reported a common clone. We used a previously validated 4-color polymerase chain reaction (PCR) assay to assess the size and V-family usage of TCR-gamma GRs in 102 concurrent and/or sequential morphologically involved biopsy specimens (91 skin and 11 lymph nodes) from 39 MF patients. This assay detected TCR-gamma clonal GRs in 89 samples (87%) from 36 patients (92%). In 24 patients (77%), an identical clonal GR was present in at least 2 skin samples. However, in one third of these patients, additional different clonal GRs were also noted. Four patients (13%) had clonal GRs that were distinct in different skin samples. In 3 patients (10%), no GR was detected in any sample. In a comparison of lymph node and skin samples, 8 patients had the identical clonal GRs at both sites, 2 patients had different clonal GRs, and 1 patient had no GR identified at either site. Independent of clinical stage, patients who had the same GR detected in multiple concurrent biopsy specimens at the time of diagnosis were more likely to have progressive disease than those who had different GRs (P =.04). Four-color TCR-gamma PCR analysis can uncover multiple distinct clonal GRs in different samples consistent with multiclonal or oligoclonal disease in a significant proportion of MF patients. Demonstration of identical clonal GRs in multiple biopsy specimens at the time of diagnosis may provide prognostic information related to disease progression.

Peripheral T-cell lymphoma

Peripheral (post-thymic) T-cell lymphoma consists of a wide spectrum of disorders with marked differences in biology and behavior. Proper classification is pivotal for evaluating treatment results, and most studies performed a decade ago lump together different disease entities and cannot be interpreted. With improved use of immunophenotyping and molecular methods for these disorders, their exact nature is better defined in the Revised European-American Lymphoma and subsequent World Health Organization (WHO) classifications. The WHO classification of post- thymic T/natural killer (NK)-cell lymphoma consists of 15 entities, including about 30% that are unclassified cases. A wide range in incidence exists between different populations, but it is likely to be lower than previously estimated. Certain entities, like nasal/nasal-type T/NK-cell lymphoma and human T-cell leukemia/lymphoma virus 1, are much more prevalent in certain racial groups and show exquisite viral association. In these entities as a group, prognosis and treatment seem inferior to those of their B-cell counterparts, but treatment must be tailored to the exact pathologic diagnosis and prognostic index. Aggressive combination chemotherapy appears to be curative for certain entities (eg, anaplastic lymphoma kinase-positive), whereas purine analogues may be useful for low-grade entities. The role of autologous and allogeneic stem cell transplantation is still poorly defined. Specific antibody-based therapy is also on the horizon.

Engagement of ILT2/CD85j in Sézary syndrome cells inhibits their CD3/TCR signaling

Extensive phenotype analysis of cutaneous T-cell lymphoma (CTCL) malignant cell lines revealed surface expression of receptors usually not detected on normal circulating CD4(+)CD45RO(+) lymphocytes. We previously found that CTCL malignant cells express the killer cell immunoglobulinlike receptor (KIR) KIR3DL2/CD158k, whereas they fail to express the other KIRs. In the present study, we report for the first time that the CD85j/immunoglobulin (Ig)-like transcript 2 (ILT2) receptor is found on Sézary cell lines and on circulating Sézary malignant CD4(+) cells, while it is hardly detectable on circulating CD4(+) lymphocytes from healthy individuals. We demonstrate that ILT2 is functional on CTCL cells, as its triggering leads to the recruitment of Src homology 2 domain-containing tyrosine phosphatase (SHP-1) and to the specific inhibition of CTCL malignant cell proliferation induced by CD3/T-cell receptor (TCR) stimulation. Interestingly, we found that separated CD4(+)ILT2(+) circulating malignant Sézary cells are less susceptible to anti-CD3 monoclonal antibody (mAb)-induced cell death than autologous CD4(+)ILT2(-) lymphocytes. Therefore, the resistance to apoptosis of Sézary cells may result from distinct mechanisms including cytokine-induced high levels of bcl-2 and specific expression of inhibitory receptors involved in lymphocyte survival.

Evidence that an identical T cell clone in skin and peripheral blood lymphocytes is an independent prognostic factor in primary cutaneous T cell lymphomas

The monoclonality of the T cell receptor gamma-chain gene was analyzed by polymerase chain reaction in skin and blood specimens of 85 patients with cutaneous T cell lymphomas including 67 mycosis fungoides, seven Sézary syndromes, and 11 CD30- nonepidermotropic cutaneous T cell lymphomas. A cutaneous T cell clone was detected in 69% of mycosis fungoides and 100% of Sézary syndromes. This frequency varied according to the clinical stage: 57% in early stages (Ia-IIa) to 96% in advanced stages (IIb-IV, Sézary syndrome). A peripheral blood T cell clone was detected in 42% of early stages and in 74% of late stages but was identical to the cutaneous one in 15% and in 63%, respectively. A significant association between initial clinical stage and T cell monoclonality was observed. In nonepidermotropic cutaneous T cell lymphomas, T cell monoclonality was detected in 55% of skin and 36% of blood samples. Univariate and multivariate analyses showed that, besides the initial clinical stage, an identical cutaneous and blood T cell clone was an independent prognostic factor for disease progression of mycosis fungoides/Sézary syndrome (hazard ratio 3.4, 95% confidence interval 1.4-9.9). Parallel polymerase chain reaction study of skin and blood specimens may therefore provide an initial prognostic marker that could help to monitor therapeutic strategies. A fully prospective study, with simultaneous therapeutic trials, needs to be done to confirm our findings and to include treatment variables in the statistical analysis.

Detection of clonal T cell receptor gamma gene rearrangements in cutaneous T cell lymphoma by LightCycler-polymerase chain reaction

Cutaneous T cell lymphoma is thought to be characterized by a monoclonal T cell infiltrate in the skin that can be detected by polymerase chain reaction-based amplification of T cell receptor gamma gene rearrangements. We sought to establish a new, simple, and fast LightCycler-based real-time polymerase chain reaction assay for the detection of monoclonality in cutaneous T cell lymphoma, which was suitable for routine laboratory application. Monoclonal T cell receptor gamma gene rearrangements were detected by polymerase chain reaction with consensus primers using: (i) a thermocycler followed by polyacrylamide gel electrophoresis; (ii) a Light Cycler followed by melting curve analysis; and (iii) a LightCycler and subsequent polyacrylamide gel electrophoresis. The detection limit of monoclonal Jurkat T cells diluted in polyclonal peripheral blood mononuclear cells was: (i) 1--3% by thermocycler--polymerase chain reaction and polyacrylamide gel electrophoresis; (ii) 10% by LightCycler--polymerase chain reaction and melting curve analysis; and (iii) 1% by LightCycler--polymerase chain reaction and polyacrylamide gel electrophoresis. In skin biopsies of 22 cutaneous T cell lymphoma patients, a monoclonal or biclonal T cell infiltrate was detected in: (i) 15 of 22 (68%) by thermocycler--polymerase chain reaction and polyacrylamide gel electrophoresis; (ii) 13 of 22 (59%) by LightCycler--polymerase chain reaction and melting curve analysis; and (iii) 16 of 22 (72%) by LightCycler--polymerase chain reaction and polyacrylamide gel electrophoresis. All three techniques revealed negative results in skin biopsies from 26 patients with benign dermatitis. In conclusion, LightCycler--polymerase chain reaction and melting curve analysis is a fast, simple and specific method to detect monoclonal T cell infiltrates in cutaneous T cell lymphoma. Sensitivity of LightCycler--polymerase chain reaction and polyacrylamide gel electrophoresis is slightly higher compared with sensitivity of thermocycler--polymerase chain reaction and polyacrylamide gel electrophoresis. Melting curve analysis, however, is less sensitive compared with polyacrylamide gel electrophoresis, and in case of negative results of the melting curve analysis, it is recommended to resolve LightCycler--polymerase chain reaction samples by gel electrophoresis.

The value of clonality in the diagnosis and follow-up of patients with cutaneous T-cell infiltrates

The diagnosis of early stages of cutaneous T-cell lymphoma (CTCL) is often difficult, especially for lesions that are at the borderline between reactive and neoplastic skin T-cell infiltrates. T-cell monoclonality in these lesions is considered by some to be an important prognostic factor of neoplastic evolution, whereas others claim that clonality can also be found in benign skin infiltrates and is therefore of limited diagnostic value. To address this controversy, the authors analyzed retrospectively eight patients with lymphocytic skin lesions who progressed to CTCL, and three patients with recurrent T-cell lymphocytic infiltrates who had not developed CTCL. From a total of 65 biopsies of eight progressing patients, 32 were diagnosed as histologically malignant and 33 were diagnosed as benign or borderline. The authors found clonality by either polymerase chain reaction or Southern blot analysis in 88% of malignant and in 79% of nonmalignant lesions. None of the 37 biopsies of non-progressing patients was clonal. These results indicate strongly that the presence of monoclonality in T-cell skin infiltrates is related closely to the risk of developing CTCL. The value of clonality as a marker of malignancy is supported by the absence of T-cell clonal populations in all infiltrates from patients who had not progressed to lymphoma.

Erythrodermic cutaneous T-cell lymphoma with disseminated pustulosis. Production of high levels of interleukin-8 by tumour cells

Interleukin (IL) -8 is a neutrophil chemoattractant cytokine with proinflammatory and growth-promoting activities, which is involved in the pathogenesis of several inflammatory diseases. It is found in high amounts in lesional biopsies of pustular diseases such as psoriasis and palmoplantar pustulosis. We report a 50-year-old woman with a 10-year history of erythroderma with disseminated pustulosis. Skin biopsies showed an epidermotropic infiltrate composed of atypical CD4+ CD8+ lymphocytes with numerous admixed neutrophils. Peripheral blood flow cytometric analysis revealed a major clonal subset of CD3+ CD4+ CD8+ T-cell receptor Vbeta22+ atypical lymphocytes. Bone marrow biopsy, lymph node biopsy and computed thoracoabdominal tomography were normal. Serologies for human T-cell lymphotropic virus type I and human immunodeficiency virus were negative. Our patient's status deteriorated despite topical (nitrogen mustard, psoralen plus ultraviolet A) and systemic (interferon, methotrexate, multiagent chemotherapy) treatments, and she finally died. We showed that our patient's peripheral blood lymphocytes (PBL) spontaneously produced high amounts of IL-8. In contrast, PBL of patients with classical Sézary syndrome produced lower amounts of IL-8. The production of IL-8 by tumour T cells could explain this unusual clinical and histopathological presentation of cutaneous T-cell lymphoma as disseminated pustulosis.

Detection of T-cell receptor-gamma gene rearrangement in lymphoproliferative disorders by temperature gradient gel electrophoresis

OBJECTIVE

Polymerase chain reaction amplification of DNA for T-cell receptor (TCR) gene rearrangement analysis is helpful in the evaluation of T-cell lymphoproliferative disorders. Detection of polymerase chain reaction products is limited by the poor resolution of bands analyzed by agarose or polyacrylamide gel electrophoresis. To improve the detection of a clonal T-cell population, we used temperature gradient gel electrophoresis (TGGE) as an alternative method for analysis of TCR gene rearrangement.

DESIGN

One hundred eighteen archival DNA samples were randomly selected based on previous Southern blot analysis results. Samples included 58 T-cell neoplasms with positivity for TCR beta gene rearrangement, 22 cases of reactive hyperplasia with germline pattern for both TCR beta and J(H), and 38 patients with B-cell lymphoma. MOLT-16, a T-cell lymphoblastic cell line, was used for the sensitivity assay. Polymerase chain reaction was performed using GC-clamped multiplex primers to amplify the TCR gamma locus and was analyzed by TGGE. The range of temperature gradients was empirically determined for optimal resolution of bands.

RESULTS

The sensitivity of TGGE was 0.1% when DNA from the MOLT-16 cell line was serially diluted with DNA from reactive lymphoid tissue. Fifty-four (93%) of 58 T-cell neoplasms with TCR beta gene rearrangements showed rearrangement patterns by TCR gamma TGGE, and only 1 of 60 samples (reactive or B-cell lymphomas) showed evidence of gene rearrangement by TGGE. Patients with T-cell neoplasm and involvement of multiple sites showed an identical migration pattern by TGGE analysis.

CONCLUSION

We demonstrate that TGGE is an effective method for analysis of TCR gene rearrangement in the evaluation of nodal and extranodal lymphoid lesions.

Diagnostic value of dominant T-cell clones in peripheral blood in 363 patients presenting consecutively with a clinical suspicion of cutaneous lymphoma

It is now widely accepted that polymerase chain reaction (PCR) analysis of cutaneous T-cell clonality is of diagnostic value in cutaneous T-cell lymphomas (CTCLs) and most helpful in the diagnosis of mycosis fungoides (MF). However, the diagnostic and prognostic value of circulating clonal T cells remains unclear. We studied T-cell clonality in the peripheral blood (PB) and the cutaneous lesion, sampled at the same time, in 363 consecutively seen patients with a clinical suspicion of cutaneous lymphoma. Using a PCR technique providing a specific imprint of T-cell clones (PCRγ–denaturing gradient gel electrophoresis), we found that detection of identical circulating and cutaneous T-cell clones was associated with the diagnosis of CTCL (P &lt; .001). Detection of circulating tumor cells in patients with MF was infrequent (12.5%), except in those with erythrodermic MF (42%; P = .003). Moreover, among the 46 patients who had identical circulating and cutaneous T-cell clones, 25 (56%) had erythroderma. The finding of a dominant clone in the PB but not in the skin was frequent, regardless of the clinicohistologic classification; it occurred in 30% of patients with CTCL, 41% with non-CTCL malignant infiltrates, and 34% with benign infiltrates. This pattern was significantly more frequent in patients over 60 years of age (P &lt; .002), even in the CTCL group (P &lt; .01). In conclusion, dominant T-cell clones detected in the PB of patients with MF by using a routine PCR technique are rarely tumoral and are more often related to age. A multicenter prospective study is under way to establish the prognostic value of circulating tumor cells.

Detection of a peripheral blood T cell clone is an independent prognostic marker in mycosis fungoides

T cell receptor gene analysis is a sensitive method for assessment of peripheral blood involvement in mycosis fungoides. This study uses polymerase chain reaction/single-strand conformational polymorphism (PCR/SSCP) analysis of the T cell receptor gamma gene and relates the results to skin stage and outcome in mycosis fungoides. Seventy-five peripheral blood samples from 66 patients were obtained from 1990 onwards and subjected to PCR/SSCP. Both Southern blot analysis and PCR/SSCP analysis were performed on 63 samples from 56 patients. Fourteen patients had T1 disease (12 IA, two IIA), 20 T2 (14 IB, five IIA, one IVA), 29 T3 (24 IIB, two IVA, three IVB, two patients tested at both T2 and T3), and five T4 (all III). The percentage of positive samples was higher with PCR/SSCP than with Southern blot analysis (29 of 63 vs eight of 63 samples, p < 0.001), and the percentage of positive samples increased with each stage (21% at T1, 35% at T2, 58% at T3, and 71% at T4). Proportional hazards analysis corrected for age, skin, and lymph node stage showed that the presence of a peripheral blood clone is associated with a worse outcome (p = 0.03, CI 1.1-6.03). These results indicate that the presence of a peripheral blood clone is an independent prognostic variable in patients with mycosis fungoides after correcting for age, skin, and lymph node stage, and that peripheral blood involvement is present in a large proportion of patients with early stage mycosis fungoides.

KEYWORDS

polymerase chain reaction/single-strand conformational polymorphism/T cell receptor gene rearrangement. J Invest Dermatol 114:117-121, 2000