Mycosis fungoides in pediatric patients: Clinical features, diagnostic challenges, and advances in therapeutic management

Mimicry unveiled: The challenging diagnosis of pigmented purpura-like mycosis fungoides initially misdiagnosed as pigmented purpura

Key Clinical Message

Unlike most cases, the lesions were localized to the dorsum of the hand, lacked pruritus (itching), and did not exhibit "sperm-like blood vessels," which are typically pathognomonic to classical MF.

Abstract

The study presents a rare case involving a 44-year-old woman who developed a skin condition on the base of her left thumb. Initially misdiagnosed as pigmented purpura, the need for further investigation arose to determine the nature of the condition accurately. The medical evaluation encompassed a comprehensive analysis of the patient's skin ailment. A series of diagnostic examinations were conducted to ascertain the underlying cause. Although routine blood tests yielded unremarkable results, the distinct characteristics of the rash prompted a more thorough investigation. Subsequent assessment revealed that the skin condition was not pigmented purpura, as initially presumed, but rather a manifestation of cutaneous T-cell lymphoma (CTCL) known as mycosis fungoides (MF). MF is an infrequent lymphoma predominantly affecting individuals aged 45-65, exhibiting a male-to-female sex ratio of 2:1. The annual incidence of MF ranges from 0.3 to 0.96 cases per 100,000 individuals. The woman's skin exhibited discrete patches adorned with colored dots, progressively thickening and pigmentation. Notably, the absence of pruritus did not dispel suspicion. This case underscores the significance of accurately diagnosing uncommon dermatological disorders to facilitate appropriate medical intervention. The unique appearance of the rash and its distinctive features, despite normal blood results, enabled the identification of MF. The patient's treatment encompassed a combination of steroids and narrowband UV therapy. Vigilance, continued research, and heightened awareness are paramount for early intervention and improved patient outcomes. Such efforts contribute to an enhanced understanding of the complexities of this condition.

Five paediatric patients with mycosis fungoides and our approach to provide age-appropriate information and psychological support

Cutaneous lymphoproliferative diseases in childhood are rare and they are clinically and pathologically heterogeneous, which makes their diagnosis challenging. Although there is limited long-term data and guidance on management, evidence suggests these to be different conditions from cutaneous lymphoma in adults, highlighting the need for age-appropriate patient information. We present clinical outcomes for our paediatric cohort of five patients with mycosis fungoides, emphasizing that despite diagnostic delays, mycosis fungoides in this age group tends to yield a good prognosis. It remains uncommon to provide clinical expertise together with psychological support in a dermatology paediatric service. Here, we provide our experience in offering this combined service. In conjunction with these patients, we have co-produced an accessible patient information leaflet targeted at a younger audience for support and to clarify potential misconceptions from a diagnosis of cutaneous lymphoma.

Paediatric Mycosis Fungoides: Clinical Variants, Treatment Modalities and Response to Therapy

Mycosis fungoides is a rare cutaneous lymphoma in the paediatric population. The aim of this study was to examine the epidemiological, clinical, and histological characteristics, as well as the treatment modalities and response to therapy of paediatric patients with mycosis fungoides. This retrospective cohort study reviewed the records of 37 paediatric patients treated at Rambam Medical Center, Israel, between 2013 and 2021. Extracted data included epidemiology, clinical presentation, histological reports, infiltrate clonality status, treatment modalities and response to therapy. The mean follow-up period was 60 months. All patients were diagnosed with stage IA or IB disease. Folliculotropic mycosis fungoides was the most prevalent variant (49%). Most patients were treated with phototherapy (90%), with a response rate of 85%, and a complete response rate of 55% after the first course. There were no significant differences in response to phototherapy between the folliculotropic or other variants (p = 0.072). Similarly, delayed diagnosis, atopic diathesis, clonality, phototherapy type or number of treatments, were not associated with response to therapy, while protracted phototherapy was associated with prolonged remission. In conclusion, mycosis fungoides in the paediatric population is an indolent disease with a favourable prognosis and potentially prolonged response to phototherapy.

Diagnosis and management of cutaneous lymphomas and lymphoid proliferations in children, adolescents and young adults (CAYA)

Cutaneous lymphomas and lymphoid proliferations (LPD) in children, adolescents, and young adults (CAYA) are a heterogeneous group of lymphoid neoplasms that present formidable diagnostic challenges to clinicians and pathologists alike. Although rare overall, cutaneous lymphomas/LPD occur in real-world settings and awareness of the differential diagnosis, potential complications, and various therapeutic approaches will help ensure the optimal diagnostic work-up and clinical management. Lymphomas/LPD involving the skin can occur as primary cutaneous disease in a patient that characteristically has lymphoma/LPD confined to the skin, or as secondary involvement in patients with systemic disease. This review will comprehensively summarize both primary cutaneous lymphomas/LPD that occur in the CAYA population as well as those CAYA systemic lymphomas/LPD with propensity for secondary cutaneous involvement. Focus on the most common primary entities occurring in CAYA will include lymphomatoid papulosis, primary cutaneous anaplastic large cell lymphoma, mycosis fungoides, subcutaneous panniculitis-like T-cell lymphoma, and hydroa vacciniforme lymphoproliferative disorder.

Suggested Guidelines for the Treatment of Mycosis Fungoides in Countries with Limited Resources

The treatment options for mycosis fungoides (MF) have been expanding but unfortunately many of the currently used treatment modalities are unavailable in Egypt and other African/Arab countries. In addition, there is a lack of consensus on the treatment of hypopigmented MF (HMF), which is a frequently encountered variant in our population. We aimed to develop regional treatment guidelines based on the international guidelines but modified to encompass the restricted treatment availability and our institutional experience. Special attention was also given to studies conducted on patients with skin phototype (III-IV). Treatment algorithm was formulated at Ain-Shams cutaneous lymphoma clinic through the collaboration of dermatologists, haematologists, and oncologists. Level of evidence is specified for each treatment option. For HMF, phototherapy is recommended as a first line treatment, while low-dose methotrexate is considered a second line. For early classical MF, we recommend Psoralen-ultraviolet A (PUVA), which is a well-tolerated treatment option in dark phenotype. Addition of either retinoic acid receptor (RAR) agonist and/or methotrexate is recommended as a second line. Total skin electron beam (TSEB) is considered a third-line option. For advanced stage, PUVA plus RAR agonist and/or methotrexate is recommended as first line, TSEB or monochemotherapy is considered a second line option. Polychemotherapy is regarded as a final option. All patients with complete response (CR) enter a maintenance and follow-up schedule. We suggest a practical algorithm for the treatment of MF for patients with dark phenotype living in countries with limited resources.

Mycosis fungoides in pediatric population: comprehensive review on epidemiology, clinical presentation, and management

Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma. However, it is rare in pediatric population. Most of the cases of pediatric MF present with hypopigmented patches and/or various other forms, which may often mimic common childhood dermatoses, thereby causing a delay in the diagnosis. There are no established treatment guidelines for pediatric MF. As the progression of childhood MF is extremely rare and it has an indolent course, it is usually diagnosed at an early stage (IA, IB, IIA), and hence phototherapy with a response rate of >80% is a well-established effective treatment in children. However, as recurrences are frequently seen on stopping the therapies, a maintenance regimen and long-term follow-up is equally important. This article reviews the epidemiological factors, clinical presentations, diagnosis, and various treatment modalities used in pediatric MF. We analyzed and compared the data of almost 616 childhood MF cases from various studies undertaken from 1988 to 2021.

Double CD4/CD8-Positive, Nonpoikilodermic Mycosis Fungoides Expressing CD56 in a Young Man

ABSTRACT

We report a case of mycosis fungoides (MF) in an 18-year-old man whose neoplastic T cells expressed CD4, CD8, and CD56, with no evidence of TCR-delta or Epstein-Barr virus (EBER) expression. Clinically, neither hypopigmentation nor hyperpigmentation nor poikilodermatous skin lesions were present, and the lesions subsided with oral corticoids and retinoids and environmental solar ultraviolet exposure. Our case represents the oldest patient reported so far with nonpoikilodermatous, CD8/CD56 MF and adds to the phenotypic diversity of MF in the pediatric population. This distinct phenotype does not seem to be linked to a more aggressive course than the classic CD-4 positive one.

Discoid (nummular) eczema in the paediatric setting - An Australian/New Zealand narrative

Discoid (nummular) eczema is a common and distinctive eczema variant, which has not been studied in depth. Although the principles of management are similar to that of classic atopic dermatitis, distinctions are made due to its unique presentation and persistent clinical course in children. Australian and New Zealand dermatologists with an interest in paediatric eczema developed a consensus narrative to assist clinicians in diagnosing and treating this subtype of eczema. Identifying triggers, potent topical corticosteroids under occlusion, skin barrier support and management of pruritus are first-line therapies, however, many eventually require systemic immunomodulatory agents.

Mycosis Fungoides Preceding Pityriasis Lichenoides et Varioliformis Acuta by Twelve Years in a Pediatric Patient

ABSTRACT

A 15-year-old boy presented to the pediatric dermatology department with long-standing patch stage CD8+ mycosis fungoides and subsequent development of recurrent pityriasis lichenoides et varioliformis acuta eruptions. There have been rare reports of patients with chronic, recalcitrant pityriasis lichenoides developing mycosis fungoides, but we believe this to be the second case of mycosis fungoides preceding a diagnosis of pityriasis lichenoides, and the first case reported in the pediatric population.

Primary cutaneous lymphomas in children: A prospective study from the Spanish Academy of Dermatology and Venereology (AEDV) Primary Cutaneous Lymphoma Registry

BACKGROUND/OBJECTIVES

Primary cutaneous lymphomas are rare in pediatric patients. The clinical and histopathological manifestations may differ from those in adults. Due to their low frequency and the insidious clinical picture, the diagnosis is usually delayed. The Spanish Primary Cutaneous Lymphoma Registry was initiated in 2016 as a multicenter registry that would allow better insight into the epidemiological, clinical, histopathological, and treatment response characteristics of patients with primary cutaneous lymphomas.

METHODS

We conducted a prospective observational cohort study of primary cutaneous lymphomas in pediatric patients participating in the Spanish Academy of Dermatology and Venereology (AEDV) Primary Cutaneous Lymphoma Registry.

RESULTS

At the time of the analysis, 10 patients under 18 years of age out of 799 all-age cases (1.25%) had been included in the registry (7 males, 3 females). The mean age at diagnosis was 9.7 years (SD: 4.8). Seven (70%) had mycosis fungoides, 2 of them had the folliculotropic variant; and 3 (30%) had primary cutaneous marginal zone B-cell lymphoma.

CONCLUSIONS

Primary cutaneous lymphomas are extremely rare in pediatric patients and usually have a good prognosis. Therefore, a high level of suspicion is necessary for the diagnosis. We suggest management by experienced physicians and follow-up into adulthood.

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.

Trends in pediatric skin cancer

PURPOSE OF REVIEW

To inform pediatric providers of the clinical characteristics, underlying genetic drivers, and therapeutic options for skin cancer arising in childhood and adolescence.

RECENT FINDINGS

The incidence of melanoma in pediatric patients has been declining in the past decades. Pediatric-specific diagnostic criteria should be utilized when assessing lesions concerning for melanoma to better account for the different presentations seen in pediatric disease compared with adults, such as an increased prevalence of amelanotic melanoma or frequent mimic of benign pediatric lesions. Pediatric melanoma often presents with a higher histopathologic stage and a higher Breslow depth as compared with adult melanoma. Pediatric nonmelanoma skin cancer including basal cell carcinoma and squamous cell carcinoma are associated with genetic conditions and immunosuppression, both iatrogenic and inherited.

SUMMARY

Melanoma in pediatric patients often presents differently from conventional adult melanoma, including Spitz melanoma and melanoma associated with congenital melanocytic nevi. Pediatric patients with nonmelanoma skin cancers should be evaluated for predisposing risk factors. More research on therapeutic options for pediatric skin cancer is vital to understanding the tolerance and response of our pediatric patients to therapies that are more frequently utilized in adult disease.