Monoclonal T-cell dyscrasia of undetermined significance associated with recalcitrant erythroderma

Cutaneous T-cell lymphomas: 2023 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or the blood involvement are generally approached with systemic therapies, including biologic-response modifiers, histone deacetylase inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

Cutaneous T-cell lymphomas: 2021 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multi-disciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with systemic therapies, including biologic-response modifiers, histone deacetylase inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

Skin colonization by circulating neoplastic clones in cutaneous T-cell lymphoma

Mycosis fungoides (MF) is a mature T-cell lymphoma currently thought to develop primarily in the skin by a clonal expansion of a transformed, resident memory T cell. However, this concept does not explain the key characteristics of MF, such as the debut with multiple, widespread skin lesions or inability of skin-directed therapies to provide cure. The testable inference of the mature T-cell theory is the clonality of MF with respect to all rearranged T-cell receptor (TCR) genes. Here, we used a whole-exome sequencing approach to detect and quantify TCR-α, β, and γ clonotypes in tumor cell clusters microdissected from MF lesions. This method allowed us to calculate the tumor cell fraction of the sample and therefore an unequivocal identification of the TCR clonotypes as neoplastic. Analysis of TCR sequences from 29 patients with MF stage I to IV proved the existence of multiple T-cell clones within the tumor cell fraction, with a considerable variation between patients and between lesions from the same patient (median, 11 clones; range, 2-80 clones/sample). We have also detected multiple neoplastic clones in the peripheral blood in all examined patients. Based on these findings, we propose that circulating neoplastic T-cell clones continuously replenish the lesions of MF, thus increasing their heterogeneity by a mechanism analogous to the consecutive tumor seeding. We hypothesize that circulating neoplastic clones might be a promising target for therapy and could be exploited as a potential biomarker in MF.

Mycosis fungoides and Sézary syndrome: 2019 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas (CTCL) are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis fungoides (MF) or Sézary syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multi-disciplinary approach to treatment. For patients with disease limited to the skin, skin-directed therapies are preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with systemic therapies. These include biologic-response modifiers, histone deacetylase (HDAC) inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

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

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multi-disciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with biologic-response modifiers or histone deacetylase inhibitors prior to escalating therapy to include systemic, single-agent chemotherapy. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

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

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral, or blood involvement are generally approached with biologic-response modifiers or histone deacetylase inhibitors before escalating therapy to include systemic, single-agent chemotherapy. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.

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

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

TNMB (tumor, node, metastasis, and blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or blood involvement are generally approached with biologic-response modifiers or histone deacetylase inhibitors prior to escalating therapy to include systemic, single-agent chemotherapy. Multiagent chemotherapy (e.g., CHOP) may be employed for those patients with extensive visceral involvement requiring rapid disease control. In highly selected patients, allogeneic stem-cell transplantation may be considered.

Lymphoproliferative disorders associated with hypereosinophilia

Hypereosinophilia, defined as peripheral blood eosinophil counts > 1,500/μL, may complicate the course of various lymphoproliferative disorders. Among these, Hodgkin lymphoma (HL) and certain peripheral T-cell lymphomas (PTCLs) derived from CD4 cells, including Sezary syndrome (SS), adult T-cell leukemia/lymphoma (ATLL), and angioimmunoblastic T-cell lymphoma (AITL), are most commonly associated with increased reactive eosinophilopoiesis. Rarely, marked hypereosinophilia (HE) may occur in the setting of acute B-cell lymphoblastic leukemia, with a substantial impact on disease course. The mechanisms leading to blood and tissue eosinophilia in the setting of lymphoproliferative disorders, as well as the clinical complications and prognostic implications of hypereosinophilia, are discussed in this review.

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

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis fungoides (MF) or Sézary syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

Tumor, node, metastasis, and blood (TNMB) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral, or blood involvement are generally approached with biologic-response modifiers, denileukin diftitox, and histone deacetylase inhibitors before escalating therapy to include systemic, single-agent chemotherapy. Multiagent chemotherapy may be used for those patients with extensive visceral involvement requiring rapid disease control. In highly-selected patients with disease refractory to standard treatments, allogeneic stem-cell transplantation may be considered.

Folliculotropic T-cell lymphocytosis as a distinct form of pilotropic T-cell dyscrasia

Cutaneous T-cell dyscrasia represents a heterogeneous group of persistent clonal and usually epitheliotropic T-cell infiltrates with a seemingly low risk for progression to mycosis fungoides (MF). Mucin-poor folliculotropic T-cell lymphocytosis is the least well characterized with only a few anecdotal case reports. Cases of folliculotropic lymphocytosis were retrieved via a natural language search from 2 dermatopathology databases. Comprehensive light microscopic, phenotypic, and molecular studies were conducted. There were 12 females and 12 males, with mean age of 41 years. There were 2 main clinical presentations: facial erythematous infiltrative papules and/or nodules vs extremity and truncal solitary, large, scaly plaques. The mean duration of the lesions was 3 years. Progression to follicular MF was noted in 1 case. Migration of small lymphocytes into the superficial portions of the hair follicle unaccompanied by other inflammatory cells or mucin was observed; lymphocytes with a cerebriform appearance could be seen. The CD4/CD8 ratio was more than 5:1 with significant reductions in the expression of CD62L and CD7. Of 20 cases tested, 5 showed monoclonality. Folliculotropic T-cell lymphocytosis is a form of pilotropic T-cell dyscrasia distinct from MF and alopecia mucinosa; the course seems indolent in most cases.

Flow cytometric detection of peripheral blood involvement by mycosis fungoides and Sézary syndrome using T-cell receptor Vbeta chain antibodies and its application in blood staging

Peripheral blood involvement has been recognized as an adverse prognostic factor in patients with mycosis fungoides and Sézary syndrome. However, accurate identification and enumeration of the neoplastic cells in these diseases can be challenging. We assessed the clinical utility of flow cytometric immunophenotypic analysis of T-cell receptor Vbeta expression in 82 mycosis fungoides and 6 Sézary syndrome patients, with an atypical T-cell immunophenotype, or abnormal CD4:CD8 ratio, identified from peripheral blood specimens of 723 patients submitted for routine mycosis fungoides/Sézary syndrome blood staging. To improve detection sensitivity, Vbeta expression was analyzed on gated CD3+CD4+ T cells or T cells with an aberrant immunophenotype, if present. The flow cytometric results were compared with traditional morphologic assessment (n=88) and molecular methods to assess the T-cell receptor gamma or beta genes (n=41 tested in parallel). Flow cytometric immunophenotyping yielded a clonal Vbeta pattern in 60/82 mycosis fungoides and 6/6 Sézary syndrome patients. By contrast, flow cytometric Vbeta was negative in all 10 healthy donors and 18 control patients, showing a specificity of 100% and concordance with molecular testing of 86%. Using flow cytometric Vbeta results instead of morphologic assessment, 12 patients were upstaged from B1 to B2, and 20 patients from B0 to B1 (P<0.0001). The 12 upstaged B2 patients had no morphologic evidence of involvement, but had an aggressive clinical course similar to those staged by traditional morphologic assessment (median survival 27 vs 41 months, log-rank P=0.701). In 30/44 patients with a tumor-associated Vbeta expression, a single Vbeta tube was used to monitor treatment response. In conclusion, flow cytometric Vbeta analysis is rapid and convenient, can assess T-cell clonality and tumor quantity simultaneously, and is useful both in initial blood staging and monitoring tumor burden during therapy in patients with mycosis fungoides or Sézary syndrome.

Clonal lymphocytic populations in Philadelphia-negative chronic myeloproliferative disorders: is the T-cell clonality of 'undetermined' significance (TCUS) linked to a worse clinical outcome?

This study examined the clonality of B- and T-cells by PCR in 83 patients with Philadelphia-negative myeloproliferative disorders (Ph-MPD), to investigate its clinical and morphological correlates. Clonal lymphocytic populations were found in 23% of patients (T: n = 20, B: n = 3), with no frequency differences between ET, CIMF and PV. At the presentation, patients with clonal bands were older (58.1+/-13.8 vs 47.5+/-14.6, p = 0.0039), but did not differ in other clinical parameters. After the median follow-up of 21 months they were less likely to be asymptomatic (11.8% vs 41.1%, p = 0.029). The T-cell clonality was the strongest predictor of the symptomatic last follow-up by discriminant function analysis, surpassing the patient's age. This surprising negative prognostic impact of lymphocyte clonality in Ph-MPD may result from this phenomenon to be a better measure of the 'hematopoietic biologic age' than the metrical age itself.

T-cell dyscrasias in dermatopathology

Recently, the term "T-cell dyscrasia" has been introduced into the literature of dermatology and dermatopathology. We review the historical background of the term dyscrasia and assess its definition and usage of it in hematopathology and dermatopathology. We learned that the term dyscrasia in the past was associated with meanings very different from one another and that no clear definition and no lucid concept of dyscrasia can be found anywhere in the literature of dermatology and dermatopathology. We conclude that the term dyscrasia in dermatopathology is used mainly to evade problems in interpretation of laboratory findings of a dominant T-cell clone, especially in the circumstance in which a treating physician fails to integrate molecular pathologic data with clinical features and histopathologic findings. Therefore, we suggest that the term lymphomatoid dyscrasia should be abandoned.