Mycosis Fungoides Variants

Null T-cell phenotype mycosis fungoides with aberrant CD20 and CD56 expression: A diagnostic dilemma

Mycosis fungoides (MF) represents the most common type of primary cutaneous T-cell lymphoma. Recognition of MF variants with divergent immunophenotypes is important for accurate diagnosis and appropriate management, as they can be confused with other lymphoma subtypes. We present a case of a 49-year-old male previously diagnosed with a cutaneous lymphoproliferative disorder with an unusual NK/T-cell phenotype. He presented with a 10-year history of pelvic girdle rash involving the right hip and upper thigh. The lesions were characterized as atrophic patches concentrated in sun-protected areas and involving 10% of the body surface area. Shave biopsies revealed an atypical epidermotropic infiltrate composed of hyperchromatic small to medium-sized lymphocytes with perinuclear halos and "tagging" along the dermal-epidermal junction. The immunophenotype was unusual in that the neoplastic lymphocytes showed complete loss of pan T-cell antigens along with expression of CD56, cytotoxic markers, and weak CD20. All other B-cell markers were negative. The combination of clinical findings, in addition to the histopathologic and immunophenotypic profile, were diagnostic of null T-cell phenotype MF with aberrant expression of CD56 and CD20. Null T-cell phenotype MF is very uncommon, can be diagnostically challenging, and can mislead the diagnosis of aggressive lymphoma subtypes.

Interstitial mycosis fungoides: A rare presentation of mycosis fungoides with overlapping granulomatous and folliculotropic features

BACKGROUND

Interstitial mycosis fungoides (IMF) is a rare subtype of mycosis fungoides (MF) characterized by atypical lymphocytes infiltrating the reticular dermis between collagen bundles with limited epidermotropism and variable granulomatous features.

METHODS

Retrospective single institution review of 31 cases of IMF including clinical characteristics, disease course and pathological features.

RESULTS

Our cohort was predominately male (19; 61%, M:F 1.6:1) with a mean age at diagnosis of 43 years (range 11-85), mean signs/symptoms duration of 7 years prior to diagnosis, and 6 years mean follow-up duration. Clinically, patients often exhibited symmetric ill-defined patches/plaques involving intertriginous regions with tan-yellow hyperpigmentation and follicular-based papules, wrinkling, and alopecia. Lymphadenopathy was noted in seven patients. Fifteen (52%) patients were in near or complete clinical remission at the latest follow-up. T-cell receptor gene rearrangement was positive in 23/24 (96%) cases. Histopathologically, atypical cells were small-medium, CD4+ (29; 94%) or rarely CD4+/CD8+ (1; 3%) lymphocytes infiltrating the reticular dermis with thickened collagen bundles (27; 87%), multinucleated giant cells (12; 39%), and often tracing along adnexa with subtle folliculotropism (12/20; 60%).

CONCLUSIONS

Our study demonstrates IMF is an indolent subtype of MF with distinct features, including frequent granulomatous and subtle follicular involvement resulting in alopecia.

Report on a Rare Case of Limited CD4/CD8 Double-Positive Paget Reticulosis with Literature Review

Restricted pagetoid reticulosis, also known as Woringer-Kolopp disease, represents a rare cutaneous lymphoproliferative disorder categorized as an isolated variant of mycosis fungoides. This report presents a case involving limited pagetoid reticulosis affecting the right upper extremity in a 25-year-old female. The patient had been experiencing plaques on the right upper extremity for a decade. Dermatologic examination revealed well-defined scaly plaques on the right forearm, surrounded by hyperpigmented patches. Skin histopathology demonstrated atypical mononuclear cell infiltration in the lower part of the epidermis, forming nests. Immunohistochemistry indicated CD3+, CD4+, CD5+, CD7+, CD8+, CD30+, and Ki-67-positive staining. Additionally, CD20, CD79α, and PD-1 were negative. Monoclonal rearrangement of T-cells was identified in TCR β and TCR γ through clonality assessment. The diagnosis of limited paget-like reticulocyte hyperplasia was established, leading to surgical resection. A review of the literature affirmed the variable immunophenotype of pagetoid reticulosis, with atypical cells exhibiting four types: (1) CD3+, CD4+, CD8+-type; (2) CD3+, CD4-, CD8+-type; (3) CD3+, CD4-, CD8-type; and (4) CD3+, CD4+, CD8+-type-relatively uncommon in the restrictive type. This case report details the clinical features, histologic and morphologic characteristics, immunohistochemical phenotype, diagnosis, and differential diagnosis of a rare CD3+, CD4+, CD8+ limited pagetoid reticulosis. The lesion was surgically resected, and the patient underwent a 3-year follow-up to observe its prognosis.

Epidemiology and prognostic factors of 114 patients with mycosis fungoides in a Moroccan cohort: a 29-year review

Limited data regarding survival of Moroccan patients with mycosis fungoides (MF). To evaluate the clinical profile and long-term outcomes of these patients. A retrospective review of 114 MF cases diagnosed from 1993 to 2022 who were followed up for more than 6 months of diagnosis was performed. Of 114 patients, 71.9% were male and the median age at diagnosis was 56 years. Approximately 64 and 36% of the patients had an early stage and advanced stage, respectively. Median follow-up duration was 56 months, and median duration of symptoms before diagnosis was 31 months. Various subtypes were observed, including mycosis fungoides folliculotropic (12.3%), poikilodermatous (11.4%), and palmaris et plantaris MF (5.3%). The 10-year overall survival was 89% in early-stage patients and 48.8% in advanced-stage patients. Complete response to treatment occurred in 45.6%, stable disease in 16.7% and disease progression in 7.9% of patients. Older age of > 60 years, higher T-stage (T3/T4) and advanced-stage MF were statistically significant in predicting poorer outcomes in MF. Despite delay in diagnosis, most cases of MF in Morocco were diagnosed in early stages. We observed a high proportion of classic MF and favorable prognosis.

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

Primary cutaneous T-cell lymphoma: a review of the most common entities with focus on recent updates

Cutaneous T-cell lymphomas are an heterogeneous group of uncommon lymphoid neoplasms that are challenging to diagnose and require close collaboration between dermatologists, pathologists and hematologists/oncologists. This article reviews the most common cutaneous T-cell lymphomas: mycosis fungoides (both classic and variant forms) as well as its leukemic counterpart Sézary syndrome, CD30+ T-cell lymphoproliferative disorders including the ever-expanding group of lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma, and primary cutaneous CD4+ small/medium lymphoproliferative disorder. We discuss the classic clinical and histopathologic features of these lymphomas and review how they can be distinguished from reactive entities. In particularly, updates to these diagnostic categories and current controversies in classification are highlighted. Moreover, we review the prognosis and treatment for each entity. These lymphomas exhibit variable prognosis, and therefore it is important to correctly classify atypical cutaneous T-cell infiltrates for appropriate patient treatment and prognosis. Cutaneous T-cell lymphomas are at the interface of several medical specialties; this review seeks to summarize key features of these lymphomas and highlight new and emerging insights into these lymphomas.

Read the clonotype: Next-generation sequencing-based lymphocyte clonality analysis and perspectives for application in pathology

Clonality assessment using the unique rearrangements of immunoglobulin (IG) and T-cell receptor (TR) genes in lymphocytes is a widely applied supplementary test for the diagnosis of B-cell and T-cell lymphoma. To enable a more sensitive detection and a more precise comparison of clones compared with conventional clonality analysis based on fragment analysis, the EuroClonality NGS Working Group developed and validated a next-generation sequencing (NGS)-based clonality assay for detection of the IG heavy and kappa light chain and TR gene rearrangements for formalin-fixed and paraffin-embedded tissues. We outline the features and advantages of NGS-based clonality detection and discuss potential applications for NGS-based clonality testing in pathology, including site specific lymphoproliferations, immunodeficiency and autoimmune disease and primary and relapsed lymphomas. Also, we briefly discuss the role of T-cell repertoire of reactive lymphocytic infiltrations in solid tumors and B-lymphoma.

Mycosis fungoides and Sézary syndrome: clinical presentation, diagnosis, staging, and therapeutic management

Mycosis fungoides (MF) and Sézary syndrome (SS) are cutaneous T-cell lymphomas. MF is the most common cutaneous lymphoma, and it is classified into classic Alibert-Bazin MF, folliculotropic MF, pagetoid reticulosis, and granulomatous slack skin, each with characteristic clinical presentation, histopathological findings, and distinct clinical behaviors. SS is an aggressive leukemic variant of cutaneous lymphoma, and it is characterized by erythroderma, lymphadenopathy, and peripheral blood involvement by malignant cells. There is a wide range of dermatological manifestations of MF/SS, and prompt recognition is essential for early diagnosis. Skin biopsy for histopathology and immunohistochemical analysis is imperative to confirm the diagnosis of MF/SS. Histopathology may also provide information that may influence prognosis and treatment. Staging follows the TNMB system. Besides advanced stage, other factors associated with poorer prognosis are advanced age, male gender, folliculotropism in histopathology of patients with infiltrated plaques and tumors in the head and neck region, large cell transformation, and elevated lactate dehydrogenase. Treatment is divided into skin-directed therapies (topical treatments, phototherapy, radiotherapy), and systemic therapies (biological response modifiers, targeted therapies, chemotherapy). Allogeneic bone marrow transplantation and extracorporeal photopheresis are other treatment modalities used in selected cases. This review discusses the main clinical characteristics, the histopathological/immunohistochemical findings, the staging system, and the therapeutic management of MF/SS.

Pagetoid reticulosis

Pagetoid reticulosis (PR) is a rare type of mycosis fungoides. Clinical symptoms of PR can mimic other skin diseases of papulosquamous, neoplastic, and infectious origin that hampers PR diagnostics. The main histopathologic feature of PR is dense intraepidermal infiltration by medium to large-size lymphocytes through the epidermis leading to pagetoid plaque formation. There are three common immunophenotypes of PR: CD4-positive T-helper phenotype (CD3+, CD4+, CD8); T-cytotoxic/suppressor (CD3+, CD4, CD8+); and double negative phenotype (CD3+, CD4, CD8). The clinical case of PR with rare immunophenotype (CD2+, CD3+, CD8+ lymphoid infiltrate) is presented. The careful analysis of the symptoms, pathomorphological and immunohistochemical data is necessary for accurate PR diagnostics.

A Comprehensive Update of the Atypical, Rare and Mimicking Presentations of Mycosis Fungoides

Introduction

Mycosis fungoides (MF) is the most frequent subtype of primary cutaneous T cell lymphomas (pCTCL). The diagnosis may be particularly difficult in the early stages as well as in atypical and rare clinical presentations. Furthermore, MF may simulate a large variety of common dermatologic disorders and patterns, both histopathologically and clinically.

Methods

A literature search was performed to provide a comprehensive update on the rare and atypical MF manifestations as well as the dermatoses and dermatological patterns that could be imitated by MF.

Results

A total of 114 publications were found describing a series of different dermatoses and dermatological patterns mimicked by MF, as well as some particular localizations of MF lesions and dermatoses that occur in preexisting MF lesions.

Conclusions

The number of dermatoses that can be imitated by MF is ever-increasing. Patients with common dermatologic conditions that prove to be treatment refractory should be biopsied without delay, and sequentially as necessary, to prevent delay in diagnosis and progression of disease. Clinicopathologic correlation is the best way of diagnosis.

Updated review on prognostic factors in mycosis fungoides and new skin lymphoma trials

BACKGROUND

Ten-year survival rates in mycosis fungoides (MF) broadly varies, however, there is no standardized prognostic index available. This is presumably due to low prevalence, heterogeneity, and diagnostic challenges in MF. Recent studies have focused on identifying objective prognostic indices by using different parameters for survival determinants. The Cutaneous Lymphoma International Prognostic Index (CLIPI) and the Prospective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) represent prototypical studies that identify prognostic factors, seeking to improve management and outcomes in early-stage MF. Detecting these factors and stratifying MF patients according to their disease progression risk may help to manage these patients more efficiently.

AIMS

Review the current literature to determine the risk factors determining prognosis in MF.

METHODOLOGY

A Comprehensive literature search was performed using electronic online databases "PubMed" and "Google Scholar" using key words 'prognostic factor', 'prognostic indicator', 'mycosis fungoides', 'Sezary syndrome', 'Skin Lymphoma', 'Cutaneous Lymphoma'. Articles published in English language were considered for the review.

RESULTS

The strongest prognostic factor in MF patients is the stage of the disease. T stage and the presence of extracutaneous disease are the most important factors for survival. Other factors that are associated with worse prognosis are male gender, age >60, presence of plaques, folliculotropism, eosinophilia and lymph node stage above N1/Nx. Elevated LDH was associated with later tumor stages and large cell phenotype at diagnosis had a better prognosis. KIR3DL2 was associated with malignant transformation.

CONCLUSION

The PROCLIPI study has assessed risk factors collected in MF patients from different countries and across different ethnicities following a rigorous clinicopathologic process. The findings presented here illustrated that disease prognosis in early stages depends on many contributing factors. Detection and stratification of such factors may allow a personalized approach to management of these patients.

Characteristics and outcomes of 727 patients with mycosis fungoides and Sézary syndrome from a Brazilian cohort

BACKGROUND

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most prevalent cutaneous lymphomas. They were not described in a large Brazilian cohort yet. We aimed, with this single-center, retrospective cohort analysis, to describe the characteristics and outcomes of MF/SS in a tertiary public health service in Brazil.

METHODS

MF/SS patients evaluated at the University of São Paulo Medical School between 1989 and 2018 were included. Data were collected at diagnosis. Demographic, clinical, histopathological, immunopathological, molecular, laboratory, and follow-up data were analyzed.

RESULTS

Among 727 patients, 92.6% (673) were diagnosed with MF, 7.4% (54) with SS. There were 51.2% (372) of males, 48.8% (355) of females. The median age was 51.8 years; it was higher in erythrodermic MF (60.2) and SS (60.9). Among MF, 41.8% (281) had classic MF, 4.9% (33) folliculotropic MF, 1.8% (12) granulomatous slack skin, and 0.3% (2) pagetoid reticulosis. Common subtypes included erythrodermic (14.1%, 95), hypopigmented (10.8%, 73), and poikilodermatous MF (10.8%, 73). Extracutaneous involvement was rare. Five, 10, 20, and 30-year overall survival rates were 97.3%, 92.4%, 82.6%, and 82.6% for early-stage, and 58.6%, 42.7%, 20.8%, and 15.4% for advanced-stage disease, respectively. After multivariate analysis, SS diagnosis, folliculotropic MF, erythrodermic MF, clinical stage, age (≥60 years), increased lactate dehydrogenase, and large cell transformation conferred poorer prognosis.

CONCLUSIONS

We observed a higher percentage of hypopigmented MF compared to the literature, and demographic (older age) and prognostic (poorer prognosis) similarities between erythrodermic MF and SS, suggesting a possible relationship between these erythrodermic lymphomas. Factors associated with a poorer prognosis were compatible with the literature.

Is it mycosis fungoides? A comprehensive guide to reaching the diagnosis and avoiding common pitfalls

Mycosis Fungoides (MF) is known as 'the great mimicker' due to its capacity to emulate several dermatoses, both in the clinic and on histology. This often leads to the diagnosis being missed or delayed, which consequently leads to poorer prognosis. For a timely diagnosis, it is crucial that the physician is aware of the various clinical and histological presentations of MF, as well as the proper diagnostic protocols. In the current review, we concisely encapsulate all the variants of MF as well has the conditions it mimics clinically and histologically. Through this, we aim to provide clinicians with a holistic picture of MF and help them determine when to suspect this disease and steps to take in order to nail the diagnosis.

Reflectance confocal microscopy may be included as part of the diagnostic algorithm of early-stage mycosis fungoides

INTRODUCTION

Reflectance confocal microscopy (RCM), a noninvasive, real-time technique of computed tomography, has been widely used for pigmentary, inflammatory, and tumor diseases of the skin.

AIM

Our main purpose was to analyze the consistency between pathological and RCM characteristics of early-stage mycosis fungoides (MF) and the utility of RCM in the diagnosis of early-stage MF.

METHODS

According to the RCM features of MF in the early stage, the biopsy sites of 40 cases of suspected MF and 20 cases of chronic inflammatory skin diseases clinically were preliminarily located. Histopathologic and immunohistochemical examinations were performed to make a diagnosis based on the diagnostic algorithm proposed by the International Society for Cutaneous Lymphomas.

RESULTS

Among the 60 patients observed, there were 12 confirming cases of MF, 14 suspecting cases, 6 not completely excluding cases, and 28 eliminating cases according to the diagnostic algorithm, as well as characteristics of RCM were typical in 8 cases, suspected in 16 cases, not excluded in 3 cases, and excluded in 33 cases. The kappa value was 0.769 (P < .01), which means there is a strong consistency between the classification by RCM and the diagnosis algorithm. MF in patch stage and plaque stage (IA to IIB) has typical characteristics of RCM, respectively.

CONCLUSIONS

RCM can be used as an objective and convenient auxiliary means to diagnose early-stage MF and may be included as part of the diagnostic algorithm of early-stage MF.

Acquired disorders with hypopigmentation: A clinical approach to diagnosis and treatment

Acquired hypopigmented skin changes are commonly encountered by dermatologists. Although hypopigmentation is often asymptomatic and benign, occasional serious and disabling conditions present with cutaneous hypopigmentation. A thorough history and physical examination, centered on disease distribution and morphologic findings, can aid in delineating the causes of acquired hypopigmented disorders. The second article in this 2-part continuing medical education series focuses on conditions with a hypopigmented phenotype. Early diagnosis and appropriate management of these disorders can improve a patient's quality of life, halt disease progression, and prevent irreversible disability.