Decoding Early Mycosis Fungoides: Histopathologic and Immunohistochemical Clues

INTRODUCTION

Primary cutaneous lymphomas, notably mycosis fungoides (MF), present diagnostic challenges in recognizing early mycosis fungoides (eMF) due to their diverse clinical and histopathologic manifestations. The aim of our study was to use adjunctive histopathologic and immunohistochemical methods in eMF cases to make an early diagnosis and to facilitate differentiation from other dermatoses.

METHODS

This retrospective study analyzed 35 cases of eMF diagnosed at a single center. Demographic and clinicopathologic data were collected, and histopathologic features were assessed. Comparative analyses were conducted with conditions mimicking eMF, including large plaque parapsoriasis (LPP), psoriasis, and chronic dermatitis. Immunohistochemistry for T-cell markers (CD3, CD4, CD8, CD2, CD7) was performed.

RESULTS

With the scoring we applied in our study, a sensitivity of 91.43% (95% CI; 76.94% to 98.20%) and specificity of 85.71% (95% CI; 69.74% to 95.19%) for distinguishing eMF from LPP. Epidermotropism emerged as a crucial histopathologic marker, with a notable absence in most cases of cutaneous dermatitis (81.6% and 80% for CD and psoriasis, respectively) (P < 0.001). Immunohistochemistry revealed a T-helper phenotype (CD4+/CD8-) in the majority of eMF cases (78.1%), while CD4+/CD8+ and CD8+/CD4- patterns were less common (28.5% and 8.5%, respectively).

CONCLUSION

This study underscores the complexities in distinguishing eMF from inflammatory skin diseases, advocating for a comprehensive diagnostic approach.

Folliculotropic mycosis fungoides associated with follicular mucinosis: A case report and mini review

Key Clinical Message

F-MF is a rare non-classic variant of MF. In the case of hair loss, this should be a diagnostic consideration. The essence of the diagnosis of F-MF is a careful medical history, physical examination, and a combination of immunohistological and molecular analyses (Cureus. 2022; 14:e21231, Ann Saudi Med. 2012; 32:283, Oman Med J. 2012; 27:134, Int J Dermatol. 2016; 55:1396, Saudi Med J. 2018; 39:994 and Case Rep Oncol. 2018; 11:436).

Abstract

Mycosis fungoides (MF) is a primary cutaneous T-cell lymphoma with multiple subtypes. Follicular MF (F-MF) is a non-classic variant of MF. Histological features entail folliculotropism and damage of the epithelium lining of the hair follicles with or without mucin deposition. A 52-year-old male patient complained of recurrent skin lesions on the scalp over 8 months. The lesions appeared suddenly, enlarged over time, and became itchy. A skin punch biopsy was performed. Histological features included mucin deposits in the epithelium of the hair follicles and dense, predominantly perifollicular atypical lymphocytes infiltrating the follicular epithelium. The lymphoid cells were composed of CD3-positive T cells (CD4/CD8-positive T cells) with a shift in favor of the former. The case was diagnosed as F-MF on an immunohistological basis. The diagnosis of F-MF is often difficult for dermatologists and dermatopathologists alike. Not only clinicopathological correlations but also immunohistochemical and molecular analysis are required.

Follicular mycosis fungoides: Clinicohistopathologic features and outcomes in a series of 12 Chinese cases

Background Follicular mycosis fungoides is a distinct variant of mycosis fungoides with a broad clinical spectrum. Recently, many studies have indicated that follicular mycosis fungoides should be divided into different subtypes with disparate prognoses. Objective To define the clinicohistopathologic features and outcomes of follicular mycosis fungoides and to identify risk factors that may be related to the prognosis of Chinese patients with follicular mycosis fungoides. Materials and methods We conducted a single-centre retrospective study and reviewed the clinical, histopathologic and immunophenotypic data of 12 patients diagnosed with follicular mycosis fungoides between 2009 and 2020 in the Department of Dermatology of West China Hospital of Sichuan university. Results A total of 12 patients (seven males and five females) with a mean age of 30 ± 14 years (age range 16-55 years) were included. Scalp and face were the most common involved sites (100%). Follicular papules, acneiform lesions, plaques, and nodules, were the main clinical presentations. Histopathological findings were consistent with the classic manifestations of follicular mycosis fungoides, including folliculotropism, perifollicular and intrafollicular lymphocytic infiltrates and mucinous degeneration. Interferon α-1b was the most common treatment. Four patients died of follicular mycosis fungoides in three years. Notably, immunohistochemical analysis revealed a decreased number of CD20+ cells in the deceased patients. Limitations This is a retrospective evaluation with a small number of cases; further prospective studies are warranted to support our inferences. Conclusion Our patients were much younger than in previous studies. The observed difference in this cohort may be explained by race, in addition to the limited number of cases. A decreased number of B cells might be associated with a poor prognosis, and more studies are necessary to discover the role of B cells in follicular mycosis fungoides as well as in mycosis fungoides.

Eyelid involvement of primary cutaneous lymphomas: A clinical perspective

Eyelids may be affected in systemic, ocular adnexal and primary cutaneous lymphomas (PCLs). The frequency of eyelid involvement in PCLs is still not well known and it is not a predilection site for any type. While primary cutaneous T-cell lymphomas (CTCLs) are more commonly seen than primary cutaneous B-cell lymphomas (CBCLs), especially mycosis fungoides (MF) as by far the most frequent type, B cell lymphomas are reported to be the commonest type in eyelid localization on the contrary. PCLs may be located on the eyelids, as the sole manifestation or in association with the involvement of other parts of the eye and elsewhere of the body. MF may present with a rich spectrum of clinical features on the eyelids mostly seen in folliculotropic subtype and advanced-stage disease. Erythematous scaly patches or plaques representing the most commonly encountered eyelid MF lesions may mimic many other dermatological conditions. Diffuse thickening, oedema, poikilodermic changes, atrophy and wrinkling are other suggestive findings of eyelid MF. Milia-like papules, madarosis and ectropion are also seen in the folliculotropic variant of MF, as ectropion is more typical for Sezary syndrome. Eyelids are also a typical location for tumoural MF which has been suggested as a poor prognostic indicator in MF. Papulonodular lesions, large tumours, ulceration, diffuse infiltration, oedema and subcutaneous atrophy on the eyelids may also be seen in other types of PCLs. Keep in mind, the rich clinical spectrum of PCLs on the eyelids may be crucial in early diagnosis in this special localization.

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.

Cicatricial Alopecia Related to Folliculotropic Mycosis Fungoides

Folliculotropic mycosis fungoides (FMF) is a particular subtype of mycosis fungoides (MF), characterized by an infiltration of neoplastic CD4+ T cells in the epidermis which can spread to all follicular structures, sebaceous glands, sweat glands and hair follicles. Clinically, FMF can exhibit various cutaneous symptoms. However, these symptoms often occur on the scalp, face and neck, which are rarely affected by conventional MF. We report cicatricial alopecia in a patient with FMF as alopecia lymphomatica. This peculiar symptom should be kept in mind as a critical differential diagnosis of scarring alopecia, leading to further investigation. Thus, an early diagnosis of FMF may be obtained.

Folliculotropic mycosis fungoides: Clinical characteristics, treatments, and long-term outcomes of 53 patients in a tertiary hospital

Folliculotropic mycosis fungoides (FMF) is characterized by a broad clinical spectrum and worse prognosis compared to classical MF. This study aimed to evaluate the clinical characteristics, treatment modalities and long-term outcome and risk factors for progression and survival of FMF patients. We conducted a single-center retrospective study and reviewed 53 patients diagnosed with FMF between 1990 to 2019 in a referral center at Ankara University, Turkey. Regarding to stage at diagnosis, 24 patients (45.3%) had advanced-stage disease (≥IIB). Follicular papules was observed in 66% and alopecia in 49.1% of the cases. Forty-three patients (81.1%) suffered from pruritus. The majority of the patients (92.4%) had at least one systemic therapy. Complete remission was achieved in 24.5% of the patients. The median time of overall survival (OS) was 50 months (range 9-324 months) and 5-year and 10-year OS was 83% and 69%, respectively. Twenty-eight (52.3%) patients progressed to more advanced stages and seven (13.2%) patients died due to MF during the follow-up period. FMF is associated with a progressive course and in most patients, skin-directed therapies were found to be inefficient to control the disease and multiple systemic therapeutic agents were required to control the disease.