Efficacy of Histologic Criteria for Diagnosing Early Mycosis Fungoides

Histology-based classifier to distinguish early mycosis fungoides from atopic dermatitis

BACKGROUND

Histopathological differentiation of early mycosis fungoides (MF) from benign chronic inflammatory dermatoses remains difficult and often impossible, despite the inclusion of all available diagnostic parameters.

OBJECTIVE

To identify the most impactful histological criteria for a predictive diagnostic model to discriminate MF from atopic dermatitis (AD).

METHODS

In this multicentre study, two cohorts of patients with either unequivocal AD or MF were evaluated by two independent dermatopathologists. Based on 32 histological attributes, a hypothesis-free prediction model was developed and validated on an independent patient's cohort.

RESULTS

A reduced set of two histological features (presence of atypical lymphocytes in either epidermis or dermis) was trained. In an independent validation cohort, this model showed high predictive power (95% sensitivity and 100% specificity) to differentiate MF from AD and robustness against inter-individual investigator differences.

LIMITATIONS

The study investigated a limited number of cases and the classifier is based on subjectively evaluated histological criteria.

CONCLUSION

Aiming at distinguishing early MF from AD, the proposed binary classifier performed well in an independent cohort and across observers. Combining this histological classifier with immunohistochemical and/or molecular techniques (such as clonality analysis or molecular classifiers) could further promote differentiation of early MF and AD.

Multidisciplinary Approach to the Diagnosis and Therapy of Mycosis Fungoides

Mycosis fungoides is the most common primary cutaneous T-cell lymphoma, characterized by skin-homing CD4+ T cells derivation, indolent course, and low-grade of malignancy. Mycosis fungoides's classic type typically onsets with cutaneous erythematous patches, plaque, and tumor. In WHO-EORTC classification, folliculotropic mycosis fungoides, pagetoid reticulosis, and granulomatous slack skin are recognized as distinct variants of mycosis fungoides, because of their clinical and histological features, behavior, and /or prognosis. Mycosis fungoides often shows diagnostic difficulties, due to its absence of specific features and lesional polymorphism. A patient's treatment requires staging. In about 10% of cases, mycosis fungoides can progress to lymph nodes and internal organs. Prognosis is poor at advanced stage and management needs a multidisciplinary team approach. Advanced stage disease including tumors, erythroderma, and nodal, visceral, or blood involvement needs skin directed therapy associated with systemic drugs. Skin directed therapy includes steroids, nitrogen mustard, bexarotene gel, phototherapy UVB, and photochemiotherapy, i.e., total skin electron radiotherapy. Systemic therapies include retinoids, bexarotene, interferon, histone deacetylase inhibitors, photopheresis, targeted immunotherapy, and cytotoxic chemotherapy. Complexity of mycosis fungoides associated with long-term chronic evolution and multiple therapy based on disease stage need a multidisciplinary team approach to be treated.

Subtlety of Granulomatous Mycosis Fungoides: A Retrospective Case Series Study and Proposal of Helpful Multimodal Diagnostic Approach With Literature Review

ABSTRACT

Granulomatous mycosis fungoides (GMF) harbors a worse prognosis compared with classic MF and remains a significant diagnostic dilemma. We analyzed clinicopathologic, immunophenotypic, and molecular characteristics of GMF to develop a diagnostic algorithm. Our methodology involved a retrospective case series study of patients with GMF from our database between 2014 and 2020. A total of 8 patients with 9 biopsies of GMF were identified. Skin manifestations had variable clinical phenotype. Histologically, all cases demonstrated atypical CD4+ T-cell infiltrate with scant in 50% (n = 4), focal 37.5% (n = 3), and absent 25% (n = 2) epidermotropism. Granuloma formation was seen in 77.8% biopsies (n = 7) with sarcoid-type granulomas in 57.1% (n = 4) and granuloma annulare-like type in 42.9% (n = 3). In 66.7% of biopsies (n = 6), the CD4:CD8 ratio was >4:1 and 66.6% (n = 6) of biopsies showed ≥50% loss of CD7 expression. T-cell receptor gene rearrangement studies performed on biopsy sections were positive in all biopsies (n = 6), whereas peripheral blood T-cell receptor gene rearrangement studies did not identify clonality. In conclusion, GMF has subtle or absent epidermotropism and variable granulomatous reaction; thus, the diagnosis requires a multimodal approach, and our proposed algorithm provides a framework to approach this diagnostic challenge.

Topical Bimiralisib Shows Meaningful Cutaneous Drug Levels in Healthy Volunteers and Mycosis Fungoides Patients but No Clinical Activity in a First-in-Human, Randomized Controlled Trial

Mycosis fungoides (MF) is a subtype of CTCL with a low incidence and high medical need for novel treatments. The objective of this randomized, placebo-controlled, double-blinded, first-in-human study was to evaluate safety, efficacy, cutaneous and systemic pharmacokinetics (PK) of topical bimiralisib in healthy volunteers (HVs) and MF patients. In this trial, a total of 6 HVs and 19 early-stage MF patients were treated with 2.0% bimiralisib gel and/or placebo. Drug efficacy was assessed by the Composite Assessment of Index Lesion Severity (CAILS) score, supported by objective measuring methods to quantify lesion severity. PK blood samples were collected frequently and cutaneous PK was investigated in skin punch biopsies on the last day of treatment. Local distribution of bimiralisib in HVs showed a mean exposure of 2.54 µg/g in the epidermis. A systemic concentration was observed after application of a target dose of 2 mg/cm2 on 400 cm2, with a mean Cavg of 0.96 ng/mL. Systemic exposure of bimiralisib was reached in all treated MF patients, and normalized plasma concentrations showed a 144% increased exposure compared to HVs, with an observed mean Cavg of 4.49 ng/mL and a mean cutaneous concentration of 5.3 µg/g. No difference in CAILS or objective lesion severity quantification upon 42 days of once-daily treatment was observed in the MF patient group. In general, the treatment was well tolerated in terms of local reactions as well as systemic adverse events. In conclusion, we showed that topical bimiralisib treatment leads to (i) meaningful cutaneous drug levels and (ii) well-tolerated systemic drug exposure in MF patients and (iii) a lack of clinical efficacy, in need of further exploration due to numerous unknown factors, before depreciation of topical bimiralisib as a novel therapeutic drug for CTCLs.

Stellenwert diagnostischer Verfahren und Risiko von Zweittumoren bei primär kutanen Lymphomen

HINTERGRUND

Primär kutane Lymphome (PCL) unterscheiden sich oft stark im klinischen Verhalten und in der Prognose von systemischen Lymphomen des gleichen histopathologischen Typs. Ziel der Studie war es, die Verteilung der PCL-Subtypen, die Zeitspanne von der Krankheitsmanifestation bis zur Diagnosestellung, den Stellenwert diagnostischer Verfahren, das Auftreten von Zweittumoren und die verschiedenen Behandlungsmodalitäten im Rahmen des Krankheitsverlaufs zu untersuchen.

PATIENTEN UND METHODIK

Retrospektive Analyse von 152 Patienten mit PCL, die von 2010-2012 an der Universitäts-Hautklinik Tübingen behandelt wurden.

ERGEBNISSE

105 Patienten mit primär kutanem T-Zell-Lymphom (CTCL) (69,1 %) und 47 Patienten mit primär kutanem B-Zell-Lymphom (CBCL) (30,9 %) wurden eingeschlossen. Die Zeitspanne von der Krankheitsmanifestation bis zur Diagnose betrug durchschnittlich vier Jahre. Mycosis fungoides (MF) (47,4 %) wurde am häufigsten diagnostiziert. Die First-Line-Therapien umfassten hier entweder eine alleinige Phototherapie (PUVA, n = 48; UVB 311 nm, n = 7) oder Kombinationstherapien (PUVA mit systemischen Retinoiden, n = 18). Häufigste Second-Line-Therapie war Interferon (INF)-α plus PUVA (n = 15). Der Behandlungsverlauf war insgesamt günstig (45,2 % Remission, 28,6 % stabile Erkrankung, 22,6 % Progress). Maligne Komorbiditäten wurden im Vergleich zu einer gesunden Vergleichsgruppe häufiger beobachtet.

SCHLUSSFOLGERUNGEN

Bis zur Diagnosestellung der PCL dauert es oft mehrere Jahre. Der Wert der Staging-Verfahren ist gering. Die Behandlungsmodalitäten in früheren MF-Stadien basieren hauptsächlich auf der Phototherapie.

Importance of diagnostics and risk of secondary malignancies in primary cutaneous lymphomas

BACKGROUND AND OBJECTIVES

Primary cutaneous lymphomas (PCL) often strongly differ in clinical behavior and prognosis from systemic lymphomas of the same histopathologic type. The aim of the study was to investigate the distribution of PCL subtypes, the average time from disease manifestation to diagnosis, the importance of diagnostic procedures, the occurrence of secondary malignancies and the different treatment modalities.

PATIENTS AND METHODS

Retrospective analysis of 152 patients with PCL examined at the Department of Dermatology of the University Hospital Tübingen from 2010-2012.

RESULTS

105 patients with CTCL (69.1 %) and 47 patients with CBCL (30.9 %) were included. The average time from disease manifestation to diagnosis was four years. The most common diagnosed lymphoma was mycosis fungoides (MF) (47.4 %). First-line therapies here include phototherapy only (psoralen-UV-A [PUVA], n = 48; UVB 311 nm, n = 7) or combination therapies primarily phototherapy with systemic retinoids (n = 18). Most frequent second-line therapy was interferon (INF)-α plus PUVA (n = 15). The outcome was favorable (45.2 % remission, 28.6 % stable disease, 22.6 % progressive disease). Malignant comorbidities were observed more frequently compared to a healthy control group.

CONCLUSIONS

The diagnosis of lymphoma often takes several years. The value of staging procedures is still low and the treatment modalities for MF in earlier stages are mainly based on phototherapy.

Thickening of the basement membrane as a diagnostic sign of mycosis fungoides

The epidermal basement membrane (BM) is readily identified on skin biopsy specimens stained with periodic acid-Schiff (PAS) and PAS with diastase (PAS-D). Thickening of BM can be evidenced in several inflammatory and tumoral conditions. We noticed that most of our biopsy specimens of mycosis fungoides (MF) showed thickening of the BM. We decided to retrospectively study BM thickness in 27 biopsy specimens of MF and compare them with 27 cutaneous biopsy specimens of inflammatory diseases. We studied PAS and PAS-D stains in all cases and we measured BM thickness with an ocular micrometer. Cases were scored in a four-tiered system: 0: no detectable staining; 1+ (mild: < 5 μm); 2+ (moderate: 5-9 μm); and 3+ (prominent: >9 μm). The difference between both groups (MF vs controls) was highly significant for BM thickness values by both one- and two-tailed t tests (P < 0.0006). While only 3 biopsy specimens from the controls (11.11%) showed areas of 3+ thickening, 12 biopsy specimens of MF (44.44%) showed areas of 3+ thickening, and most cases showed diffuse, at least 2+ thickening, while the controls showed more segmental, mostly 1 or 2+ staining. We conclude that thickening of BM can be useful in the differential diagnosis with inflammatory conditions.

Evaluation of the polymerase chain reaction-based T-cell receptor β clonality test in the diagnosis of early mycosis fungoides

BACKGROUND

T-cell receptor (TCR) clonality may help establish a diagnosis of mycosis fungoides (MF). Routine clonality analysis is performed by using a polymerase chain reaction TCR- gamma assay, yet with this method, 10% to 50% of T-cell lymphomas escape detection. TCR- beta gene rearrangement is an additional assay. Data about its efficacy are controversial.

OBJECTIVE

To evaluate the role of TCR-β assay in the diagnosis of early MF.

METHODS

A retrospective study of 61 skin biopsies, 20 from patients with MF, 30 from patients suspected to have early MF, and 11 from patients with chronic inflammatory skin disease.

RESULTS

Monoclonality was detected in 16 of 20 (80%) MF cases: 15 (75%) with TCR-β and 12 (60%) with TCR-γ assay. Of the 30 suspected cases of early MF, 14 showed monoclonality with TCR-β, and only 5 of 14 showed monoclonality with TCR-γ assay. None of the chronic inflammatory condition samples showed monoclonality. Therefore, TCR-β clonality assay was more sensitive than TCR-γ in early MF (83% vs 43%; P = .002).

LIMITATIONS

This was a retrospective, relatively small study.

CONCLUSION

TCR-β showed a higher sensitivity rate compared with TCR-γ in early-stage MF. The combined use of the TCR-β and TCR-γ clonality tests can significantly improve the diagnosis rate of early-stage MF.

Validation of an algorithm based on clinical, histopathological and immunohistochemical data for the diagnosis of early-stage mycosis fungoides

Background

Diagnosis of mycosis fungoides is challenging due to the non-specificity of clinical and histopathological findings. The literature indicates an average delay of 4–6 years for a conclusive diagnosis. Refinement of the histopathological criteria for the diagnosis of patients in early stages of the disease is considered of interest.

Objectives

To study the histopathological aspects of early-stage mycosis fungoides and the applicability, in a retrospective form, of the diagnostic algorithm proposed by Pimpinelli et al.

Methods

Observational, retrospective, transversal study based on revision of histopathological exams of patients with suspected mycosis fungoides. Medical records were reviewed, and complementary immunohistochemistry performed.

Results

Sixty-seven patients were included. The most frequent histopathological features were superficial perivascular lymphoid infiltrate (71.6%), epidermotropism (68.7%), lymphocytic atypia (63.8%), hyperkeratosis (62.7%) and acanthosis (62.7%). Forty-three patients scored 4 points at the algorithm, by clinical and histological evaluation. Immunohistochemistry was performed on 23 of the 24 patients with less than 4 points. Of those 23, 22 scored 1 point, allowing a total of 61 patients (91%) with the diagnosis of early-stage mycosis fungoides.

Study limitations

Its retrospective character, reduced sample size and incomplete application of the algorithm.

Conclusions

Application of the Pimpinelli et al. algorithm, even in an incomplete form, increased the percentage of cases diagnosed as mycosis fungoides. Routine application of the algorithm may contribute to earlier and specific management and improvement of the patients’ outcome.

Mycosis Fungoides: A Clinicopathological Study of 60 Cases from a Tertiary Care Center

Background:

Mycosis fungoides (MF) is the most common primary cutaneous lymphoma. It affects usually the covered areas of the body in elderly males in 6^th and 7^th decades of life. Atypical dermal lymphoid infiltrate is seen along with epidermotropism. Nuclei of neoplastic cells are convoluted. The neoplastic cells demonstrate positivity for CD3 (Pan T) immunohistochemical stain. Majority show increased CD4 to CD8 ratio. The present study was done to study the clinicopathological features, which might be of help in reaching a correct diagnosis in these cases.

Materials and Methods:

A retrospective descriptive study was conducted on 60 reported cases of MF. The retrieved slides were reviewed for clinical and histopathological features and immunohistochemical profile.

Results:

The ages ranged from 20–84 years, mean age was 47 years. Majority (75%) of patients were male. Trunk and extremities were the sites most commonly affected. There was significant inverse correlation between epidermal thickness and tumor stage (P = 0.02). Thickened epidermis was seen in patch stage and thickness reduced with progressing stage. The intensity of dermal infiltrate and cell size was also statistically significantly linked to stage progression (P < 0.001 each). In addition, proliferation index also correlated significantly with tumor stage (P = 0.002).

Conclusion:

Clinical information and histological features are equally important in the accurate diagnosis of MF. Papillary dermal fibrosis is a useful diagnostic clue. CD4:CD8 ratio is not increased in all cases; it may be decreased or remain unchanged.

Systematic review and proposal of an in vivo reflectance confocal microscopy assessment tool for cutaneous lymphoma

BACKGROUND

Reflectance confocal microscopy (RCM) is a non-invasive imaging technique that provides dynamic information and allows in vivo monitoring, with excellent histologic correlation. In the last decade, the use of RCM for cutaneous T-cell lymphomas (CTCL) has been reported. CTCL may require multiple biopsies for diagnosis due to its equivocal clinical presentation. RCM was described as a possible tool to help determine the best site for skin biopsy. This study aims to systematically review all RCM features reported in literature for CTCL.

METHOD

A systematic literature search concerning CTCL evaluated by RCM was performed in eight electronic databases until May 2019 following PRISMA-DTA quality assessment.

RESULTS

Eighteen RCM features were described in patients with CTCL. The most frequent were: interface dermatitis (89%), epidermal lymphocytes (82%), epidermal architectural disarray (81%), and vesicle-like structure (Pautrier microabscess) (51%).

CONCLUSION

In order to establish comparable parameters among the studies identified, we proposed descriptors for CTCL features and a grading system to quantify them. This will facilitate to define the role of RCM in the diagnosis and monitoring of CTCL patients.

[Current possibilities of the differential diagnosis of plaque parapsoriasis and the early stages of mycosis fungoides]

Mycosis fungoides (MF) is the most common primary cutaneous epidermotropic T-cell lymphoma (80%). The accurate diagnosis of MF confirmed only by clinical, histological and immunohistochemical signs amounts to 50-75%.

OBJECTIVE

To investigate genetic markers (FOXP3, STAT4, IL-12B) for the early diagnosis of MF, to estimate the informative value of used diagnostic techniques (histology, immunophenotyping), and to determine clonality by the T-cell receptor γ-chain genes.

MATERIAL AND METHODS

Fifty patients with MF and plaque parapsoriasis (PP) who had been treated at the V.A. Rakhmanov Clinic of Skin and Venereal Diseases and at the National Medical Research Center for Hematology were followed up. A MF group consisted of 27 patients; a PP group included 23 patients, and a control group comprised 10 healthy individuals. The expression of the FOXP3, STAT4, and IL-12B genes was analyzed by TaqMan real time-PCR. The objectives of the study were affected skin portions from patients with MF or PP and healthy individuals.

RESULTS

The investigation revealed a increase in the expression level of STAT4 mRNA transcripts by 9 times in patients with MF compared with those with PP and by 553 times in healthy individuals. There was also a statistically significant predominance of the expression level of STAT4 mRNA transcripts in patients with spotted and plaque stages of MF (180; 318) compared with those with PP and healthy individuals, as well as a sharp decrease in those with erythrodermic MF, which was statistically significant.

CONCLUSION

MF cannot be diagnosed without comprehensively assessing the clinical, anamnestic, histological, immunophenotypic, and molecular genetic data. The expression level of STAT4 mRNA transcripts is of great importance for the early diagnosis of MF. Inclusion of the level of STAT4 expression in the list of diagnostic signs increases the accuracy of differential diagnosis of MF and PP from 59.1 to 81.8%, respectively.

Perplexing Rash: Challenges to Diagnosis and Management of Mycosis Fungoides

Mycosis fungoides is the most ubiquitous form of cutaneous T-cell lymphoma. Diagnosis is arduous, as early phases often resemble common inflammatory dermatoses. The principal histologic features of MF include medium to large-sized cerebriform mononuclear cells in single or small clusters in the epidermis. Treatment modalities are prodigious and relapses are common. The authors present a case of a 69-year-old man with mycosis fungoides, followed by a review of diagnostic modalities and phototherapeutic interventions for patients with this condition. According to literature reports, monochromatic excimer light therapy is the most advantageous and well-tolerated phototherapy modality for patients with early patch stage mycosis fungoides.

Expression of HECA-452 in Parapsoriasis and Mycosis Fungoides

We have investigated the HECA-452 expression in large plaque parapsoriasis (PP) and mycosis fungoides (MF) patients, evaluating the potential role of this biomarker in both cutaneous disorders. Skin specimens from 72 PP and 61 MF patients were selected in this study. We compared their actual histological diagnosis with their previous diagnosis and we found that all 72 PP patients had the same diagnosis as before (stable PP), while 26 out of 61 MF have a previous PP histological diagnosis (evolving PP). Our results show an increased expression of HECA-452 in MF compared to PP (p<0.01). Furthermore, evolving PP showed a significantly higher level of HECA-452 than stable PP (p< 0.05). We conclude that HECA-452 expression increases during the natural history of Mycosis Fungoides. HECA-452 could be used as a biomarker for MF and predict which PP evolves to MF.

Clinically defined subgroups of mycosis fungoides display differing histopathological features at initial biopsy

Most patients with mycosis fungoides (MF) remain in early disease stages but some progress to tumor stage. The individual course of the disease cannot be predicted. We wanted to assess the clinical and histological characteristics of the first available biopsy. An end-of-spectrum approach with two groups was used, comparing MF remaining long-term stable in T1a ('MF stable') and MF with later tumor development or present T3 stage ('MF tumor'). The clinical and histomorphological features of the initial skin biopsy were compared. Patients in the 'MF tumor' group presented initially with higher disease stages. The first biopsies of 'MF tumor' patients showed significantly higher infiltrate density and depth, more large cells and a higher proliferative index. In summary, long-term stable MF seems to differ in clinical and histopathological parameters from MF with T3 evolution/presence already at the time point of the initial biopsy. Our findings might indicate a predetermined biologic behavior.

Defining the mimics and clinico-histological diagnosis criteria for mycosis fungoides to minimize misdiagnosis

Background

Mycosis fungoides (MF) is a significant diagnostic challenge; it has various differential diagnosis especially at an early stage. Our aim was to describe mimics of MF clinically and histologically, and to define significant diagnostic criteria of the disease.

Methods

This was a retro-prospective cohort of 370 patients in whom the diagnosis of MF was suspected clinically.

Results

MF was histologically confirmed in 15.4% of cases and rejected in 84.5%. Other identified histologically diagnosis were eczema, psoriasis; nonspecific dermatitis, lichen, lupus; pseudolymphoma, parapsoriasis and toxidermia. 4 patients with palmoplantar MF were wrongly treated as eczema, and 10 patients with psoriasiform MF were initially treated as psoriasis. We also described the clinical, histological and immunohistochemistry diagnostic criteria for distinguishing MF from benign dermatosis.

Conclusions

Misdiagnosis of MF was a real problem for this study, because it shared common clinical and histological characteristics with other inflammatory diseases like eczema and psoriasis. Therefore, defining significant clinico-histological diagnosis criteria of MF would be of great help and would increase the accuracy of the diagnosis.

Syringotropic mycosis fungoides responding well to VELP chemotherapy: A case report

Mycosis fungoides (MF), a low-malignant lymphoproliferative disorder, is the most common type of cutaneous T-cell lymphoma. The current study reported a case of syringotropic MF, a rare variant of MF, which presented with reactive B cell proliferation, lymphoid follicle formation, hair loss and lymphadenopathy. The clinical manifestations of the patient were MF-like lumps. Immunohistochemical staining of AE1/AE3 showed that there were abundant infiltrated lymphocytes surrounding the syringocystadenoma. In addition, the direction of the lymphocyte arrangement was consistent with the meandering direction of syringocystadenoma. The patient did not respond to 1-month narrowband (311-nm) ultraviolet therapy; however, a good response was obtained subsequent to one cycle of chemotherapy with vincristine sulfate, etoposide, L-asparaginase and prednisone acetate (know as the VELP regimen). After 7 days of VELP chemotherapy, the skin lesions were ameliorated, hair loss was improved and lymphadenopathy disappeared. No lymphadenopathy or new skin lesions were observed during 6 months of follow-up.

T-cell clonality assessment by next-generation sequencing improves detection sensitivity in mycosis fungoides

BACKGROUND

T-cell receptor (TCR) clonality assessment is a principal diagnostic test in the management of mycosis fungoides (MF). However, current polymerase chain reaction-based methods may produce ambiguous results, often because of low abundance of clonal T lymphocytes, resulting in weak clonal peaks that cannot be size-resolved by contemporary capillary electrophoresis (CE).

OBJECTIVE

We sought to determine if next-generation sequencing (NGS)-based detection has increased sensitivity for T-cell clonality over CE-based detection in MF.

METHODS

Clonality was determined by an NGS-based method in which the TCR-γ variable region was polymerase chain reaction amplified and the products sequenced to establish the identity of rearranged variable and joining regions.

RESULTS

Of the 35 MF cases tested, 29 (85%) showed a clonal T-cell rearrangement by NGS, compared with 15 (44%) by standard CE detection. Three patients with MF had follow-up testing that showed identical, clonal TCR sequences in subsequent skin biopsy specimens.

LIMITATIONS

Clonal T-cell populations have been described in benign conditions; evidence of clonality alone, by any method, is not sufficient for diagnosis.

CONCLUSION

TCR clonality assessment by NGS has superior sensitivity compared with CE-based detection. Further, NGS enables tracking of specific clones across multiple time points for more accurate identification of recurrent MF.

Selected Inflammatory Imitators of Mycosis Fungoides: Histologic Features and Utility of Ancillary Studies

Mycosis fungoides is the most common primary cutaneous lymphoma; however, it remains a significant diagnostic challenge, in part because of the overlap with several inflammatory dermatoses. Despite advances in immunohistochemistry and molecular diagnostics, false-positive, false-negative, and indeterminate diagnoses are not uncommon. In most cases, the overall balance of morphologic, immunophenotypic, and genetic features must be considered carefully because there are few sensitive and specific clues to the diagnosis. Moreover, an appropriate clinical presentation is essential to the diagnosis and helps to favor or exclude inflammatory/reactive processes. Herein, we discuss 3 important inflammatory dermatoses that may closely simulate mycosis fungoides, and we review the use of ancillary studies in these challenging cases.

A review of survival in mycosis fungoides

OBJECTIVES

The objectives of this study are to review prior publications of survival for patients with mycosis fungoides (MF), to perform some analyses on the consolidated data, and then to consider the implications of the results.

METHODS

The data for this study comprise 18 survival curves derived from seven prior publications of long-term survival in relatively large series of patients with MF. Altogether, the study uses results from over 5,000 patients. To examine fatality, the study uses hazard functions derived from the survival curves.

RESULTS

The analyses demonstrate significant variability in survival between different groups who have studied MF, and the results document that for most patients the diagnosis of MF has little impact on fatality.

CONCLUSIONS

Although MF is considered a cutaneous lymphoma, that is, a malignancy, it may be time to reconsider low stages of MF as precursors to malignancy analogous to the precursors to malignancies of other types or organs.

[Mycosis fungoides or inflammatory dermatitis: differential diagnosis between early lymphoma and inflammation in skin biopsies]

Mycosis fungoides is a cutaneous T-cell lymphoma with protracted clinical course and progression in different stages with increasing aggressiveness. The clinical picture as well as the histopathology of mycosis fungoides within the early patch and plaque phase is difficult to delineate from some inflammatory skin diseases. Thus, the diagnosis of these early stages of the lymphoma is only possible when clinical, histopathological, and molecular features are integrated into the diagnosis, especially as none of the individual disease criteria is specific. Important clues towards the diagnosis of mycosis fungoides are cytologically abnormal epidermotropic CD4-positive T-cells causing only minor epidermal alterations, the formation of Pautrier-abscesses and basal alignment of the epidermotropic T-cells. The findings of an aberrant T-cell immunophenotype of the intraepidermal lymphoid component as well as the molecular proof of T-cell clonality are important further features. In the differential diagnosis between early stage mycosis fungoides and parapsoriasis, there remains nevertheless a diagnostic and maybe also a true biological grey zone.

The Histological Spectrum of Early Mycosis Fungoides: A Study of 58 Saudi Arab patients

OBJECTIVES

The histopathological diagnosis of Mycosis Fungoides (MF) is challenging in its early stages and can easily be confused with inflammatory dermatoses. This study aims to; (i) assess the frequency and significance of different histopathological parameters in early MF, seen in Saudi patients, and (ii) to study the utility of these parameters in differentiating between early MF and inflammatory dermatoses.

METHODS

This is a five years study of 66 skin biopsies generated from 58 patients with clinically suspicious MF lesions or early patch stage MF. These cases were retrieved from the archives of the Department of Pathology, King Khalid University Hospital, Riyadh from the year 2002 to 2006. Histological criteria were assessed and graded semi-quantitatively on a four-point scale by a dermatopathologist and two pathologists independently.

RESULTS

The histological parameters suggesting the diagnosis in early stages MF include epidermotropism, dermal fibrosis, Pautrier's micro abscesses, Basal alignment of neoplastic lymphocytes, hyperconvoluted dermal and epidermal lymphocytes and grandiosity sign (size of lymphocytes becoming larger as they migrate towards granular layer of epidermis). These parameters on univariate analysis achieved statistical significance (p<0.05) in differentiating MF from non-MF cases. In addition, hyperconvoluted dermal and epidermal lymphocytes proved to be highly reliable with high specificity and sensitivity.

CONCLUSION

The histopathological diagnosis of early MF lesions and their discrimination from inflammatory simulators can be achieved by carefully observing the hyperconvoluted dermal and epidermal lymphocytes along with the constellation of the other parameters.

Simplified flow cytometric assessment in mycosis fungoides and Sézary syndrome

By using flow cytometry with markers for CD3, CD4, CD26, and CD7, we examined the blood samples of 109 patients for abnormal T cells: 69 patients with mycosis fungoides (MF)/Sézary syndrome (SS), 31 hospitalized control subjects, and 9 patients with inflammatory skin disease. T cells were identified as quantitatively abnormal (>15% CD26- or CD7- T cells) or phenotypically abnormal (CD26- or CD7- T cells with bright or dim CD3 or CD4 or bright CD7). Patients were followed for a median of 82 months, and abnormal T cells were correlated with diagnosis, clinical outcome, and other laboratory parameters. Abnormal T-cell populations were identified in 46% of patients with MF/SS (32/69) and correlated with disease extent. Quantitative abnormalities were more frequent than phenotypic abnormalities, and CD4+/CD26- T cells were more frequent than CD4+/CD7- T cells. CD26- T cells correlated better with disease extent than did CD7 -. Increasing numbers of abnormal T cells were associated with worsening disease. Flow cytometry provides valuable information for diagnosis, prognosis, and therapeutic efficacy in MF/SS.

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.

Current approaches to diagnostics of mycosis fungoides

The authors describe strong and weak sides of current methods for diagnostics of mycosis fungoides. Diagnostics of mycosis fungoides is mainly based on the clinical presentation of this disease, which is a significant problem for a dermatovenerologist, especially at early stages of the disease when rashes are of different types. Laboratory methods used to confirm the diagnosis are microscopic examination and immunophenotypic analysis of skin biopsy samples from the affected region as well as determination of clonality of T-lymphocytes in the skin using the PCR method.

Matrix metalloproteinase-2 promoter genotype as a marker of cutaneous T-cell lymphoma early stage

The aim of the study was to investigate the DNA polymorphic genotype in MMP-2 promoter gene as a potential candidate region for the development of the cutaneous T-cell lymphoma (CTCL) and/or its progression. A total of 89 Czech patients with CTCL (including 23 patients with large plaque parapsoriasis) were compared to 198 controls of similar age and sex distribution, without personal or family history of chronic skin diseases and without personal history of malignancy. The three selected polymorphisms in the promoter of MMP-2 gene (−1575G/A, −1306C/T, and −790T/G) were determined using the PCR-based methodology with RFLP. In our cohort, the associated GGCCTT MMP-2 promoter genotype was highly significantly more frequent in CTCL-Ia stage patients compared to patients with parapsoriasis, the tests having high sensitivity and specificity (78%, 83%, resp.). To conclude, use of associated MMP-2 promoter genotype as a DNA marker might make it possible to distinguish between the patients with parapsoriasis and those with CTCL stage Ia, which could substantially improve possibilities of clinical diagnostics, therapy design, and prognosis of this serious condition in the early stages.

Primary cutaneous T-cell lymphoproliferative disorder of donor origin after allogeneic haematopoietic stem-cell transplantation

A 56-year-old male patient had a history of mantle-cell lymphoma, which was treated with polychemotherapy and reduced-intensity conditioning allogeneic haematopoietic stem cell transplantation (ASCT) from his healthy sister with an identical human leucocyte antigen profile. Six years after transplantation, the patient developed asymptomatic eczema-like cutaneous lesions. Histologically the lesions contained a dense superficial lichenoid infiltrate, mainly consisting of CD4+ atypical medium to large lymphocytes showing indented hyperchromatic nuclei. In situ hybridization for Epstein-Barr virus was negative. PCR amplification of the T-cell receptor-gamma chain gene from several lesions revealed a monoclonal rearrangement without clonal variation. Two-colour fluorescence in situ hybridization (X and Y chromosomes) and microsatellite genotyping were used to compare samples from the patient (transplant recipient), his sister (donor) and the skin biopsy sample, which confirmed that the origin of the neoplastic cells was the donor graft. To our knowledge, this is the first case of post-transplant primary cutaneous T-cell lymphoproliferative disorder after ASCT.

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.

Regarding the algorithm for the diagnosis of early mycosis fungoides proposed by the International Society for Cutaneous Lymphomas: suggestions from routine histopathology practice

BACKGROUND

Routine clinicopathologic practice is expected to refine/validate the scoring system proposed in 2005 by the International Society for Cutaneous Lymphomas (ISCL) for the diagnosing early mycosis fungoides (eMF), classical type.

METHODS

An evaluation of 72 cases of erythematous and scaling dermatoses was employed with a partial implementation of the ISCL algorithm.

RESULTS

The selected cases fulfilled the clinical criteria proposed by the ISCL; routine histopathology allowed to reach the ISCL minimum score for a diagnosis of eMF in 45 cases. A clonal T-cell population was found in 4 out of 12 cases tested with the polymerase chain reaction, three of which with an already established clinicopathologic diagnosis of eMF. An aberrant immunophenotype was found in 11 cases, all of which already labeled as eMF on the basis of clinical and histopathologic features. 6 out of 27 patients with inconclusive clinicopathologic data underwent a new skin biopsy, which allowed to reach a diagnosis of eMF in two cases.

CONCLUSIONS

The diagnosis of eMF still rests upon clinical features and conventional histology; a new skin biopsy is recommended for cases with no clear-cut diagnostic features.

In vivo reflectance confocal microscopy of mycosis fungoides: A preliminary study

BACKGROUND

Mycosis fungoides (MF) is a diagnostic challenge, frequently needing multiple and sequential biopsies to establish the diagnosis.

OBJECTIVE

Our aim was to evaluate lesions suggestive of MF using in vivo reflectance confocal microscopy (RCM) and to correlate confocal features with histopathologic findings.

METHODS

A total of 8 lesions from 7 patients either with a history of biopsy-proven MF or with lesions clinically suggestive of MF were imaged with RCM followed by a skin punch biopsy. These 8 lesions were confirmed to be MF by histopathology: patch type (n = 3), plaque type (n = 4), and tumor type (n = 1).

RESULTS

Under RCM, epidermal findings in patch lesions were subtle, as on histopathology, while the most prominent changes were observed in plaque type MF. At the level of the epidermis, weakly refractile oval to round structures within the spinous layer were observed in all MF lesions, but were difficult to distinguish from surrounding keratinocytes; these structures corresponded to epidermotropic lymphocytes on histopathology. In plaque-type lesions, vesicle-like dark spaces filled with collections of monomorphous weakly refractile oval to round cells were clearly elucidated by RCM; these structures corresponded to Pautrier's microabscesses on histopathology. RCM was also able to demonstrate spongiosis in the MF lesions, with findings of epidermal architectural disarray, areas with thickened and blurred intercellular demarcations, and epidermal cells with elongated nuclei. At the dermoepidermal junction, the basal cells surrounding the dermal papillae appeared as only faintly refractile rings on RCM. This feature corresponded with histopathologic findings of basal layer infiltration by tumor cells with permeation of rete ridges, thus, obscuring the dermoepidermal interface. Examination of the dermis under RCM for all the MF lesions showed weakly refractile structures, but was limited by loss of detail and contrast below the dermoepidermal junction.

LIMITATIONS

Because of limited imaging depth, RCM did not visualize dermal infiltration by tumor cells in tumor-type MF. Epidermotropic lymphocytes appeared weakly refractile under RCM and were difficult to distinguish from surrounding keratinocytes as a result of minimal difference in contrast. Other limitations on RCM include some similarity in findings with spongiotic and lichenoid dermatitides, and an inability to distinguish specific cell types. Moreover, this study did not address the inherent heterogeneity of MF lesions, but was primarily focused on correlating RCM and hematoxylin-eosin histopathology of the included cases.

CONCLUSION

Features correlating well to histopathology are observed on RCM of MF lesions; however, the specificity of these findings needs to be assessed.

T-cell/NK-cell lymphomas: A review

T-cell neoplasms are a group of heterogeneous neoplasms that present a challenge in management. Accurate diagnosis and classification are necessary for proper treatment. This dilemma is exemplified by continuous upgrading of classification systems in an effort to better understand these diseases. The spectrum of management varies from observation and monitoring to prompt aggressive multimodality treatment to achieve optimal outcomes. Allogeneic transplant has been successful in a minority of cases with the possibility of cure; however this approach is still largely experimental. Molecular studies such as gene expression profiling are expected to offer exciting insight into the biology of these diseases. Novel therapeutic approaches continue to be explored, however will probably require larger clinical trials to establish their utility over the current standard.

Histopathologic-molecular correlation in early mycosis fungoides using T-cell receptor gamma gene rearrangement by polymerase chain reaction with laser capture microdissection

BACKGROUND/PURPOSE

Early mycosis fungoides (MF) is difficult to distinguish from other benign inflammatory dermatoses. We evaluated clonal T-cell receptor (TCR) gamma gene rearrangement by polymerase chain reaction (PCR) as a surrogate to histologic diagnosis in early MF.

METHODS

Twenty paraffin-embedded skin biopsies from nine patients diagnosed with MF were included. Two multiplex PCR encompassing various Vgamma and Jgamma regions were used to detect TCRgamma gene rearrangements. Histologic diagnoses were categorized as "diagnostic", "consistent", "suggestive", or "nondiagnostic". We compared TCRgamma PCR results with histologic parameters to determine the differences between PCR-positive and PCR-negative groups.

RESULTS

TCRgamma PCR was positive in 53% (8/15) of the patch stage, in 100% (2/2) of the plaque stage, and in 100% (3/3) of the tumor stage. TCRgamma PCR was positive in 50% (4/8) of the specimens in both the diagnostic and consistent of MF groups, 71% (5/7) in the suggestive of MF group. We found that inflammation was more severe in PCR-negative specimens. Papillary dermal fibrosis was common, and differed significantly between PCR-positive and PCR-negative groups (p = 0.01). T-cell monoclonality was detected in one nondiagnostic lesion in a patient with psoriasis and MF.

CONCLUSION

TCRgamma PCR allows the diagnosis of MF in patients with lymphocyte-poor lesions, suggestive of MF pathologically. TCRgamma PCR is more likely to be negative with moderate to severe inflammation, particularly with papillary dermal fibrosis. We suggest that the ratio of malignant clonal to reactive T-cells is critical for MF diagnosis.