Paediatric cutaneous lymphomas: a review and comparison with adult counterparts

Paediatric-onset lymphomatoid papulosis: results of a multicentre retrospective cohort study on behalf of the EORTC Cutaneous Lymphoma Tumours Group (CLTG)

BACKGROUND

Lymphomatoid papulosis (LyP) is a rare cutaneous T-cell lymphoproliferative disorder. Comprehensive data on LyP in the paediatric population are scarce.

OBJECTIVES

To characterize the epidemiological, clinical, histopathological and prognostic features of paediatric LyP.

METHODS

This was a retrospective multicentre international cohort study that included 87 children and adolescents with LyP diagnosed between 1998 and 2022. Patients aged ≤ 18 years at disease onset were included. LyP diagnosis was made in each centre, based on clinicopathological correlation.

RESULTS

Eighty-seven patients from 12 centres were included. Mean age at disease onset was 7.0 years (range 3 months-18 years) with a male to female ratio of 2 : 1. Mean time between the onset of the first cutaneous lesions and diagnosis was 1.3 years (range 0-14). Initial misdiagnosis concerned 26% of patients. LyP was most often misdiagnosed as pityriasis lichenoides et varioliformis acuta, insect bites or mollusca contagiosa. Erythematous papules or papulonodules were the most frequent clinical presentation. Pruritus was specifically mentioned in 21% of patients. The main histological subtype was type A in 55% of cases. When analysed, monoclonal T-cell receptor rearrangement was found in 77% of skin biopsies. The overall survival rate was 100%, with follow-up at 5 years available for 33 patients and at 15 years for 8 patients. Associated haematological malignancy (HM) occurred in 10% of cases (n = 7/73), including four patients with mycosis fungoides, one with primary cutaneous anaplastic large cell lymphoma (ALCL), one with systemic ALCL and one with acute myeloid leukaemia. If we compared incidence rates of cancer with the world population aged 0-19 years from 2001 to 2010, we estimated a significantly higher risk of associated malignancy in general, occurring before the age of 19 years (incidence rate ratio 87.49, 95% confidence interval 86.01-88.99).

CONCLUSIONS

We report epidemiological data from a large international cohort of children and adolescents with LyP. Overall, the disease prognosis is good, with excellent survival rates for all patients. Owing to an increased risk of associated HM, long-term follow-up should be recommended for patients with LyP.

Paediatric cutaneous lymphomas including rare subtypes: A 40-year experience at a tertiary referral centre

BACKGROUND

Primary cutaneous lymphomas are neoplasms of the immune system with a distinct tropism for the skin and an absence of extracutaneous manifestations at the time of diagnosis. Studies focusing on cutaneous lymphomas in children and adolescents remain scarce and often do not encompass the rare subtypes.

OBJECTIVES

To address this knowledge gap by describing the clinical, histological and molecular characteristics of a large group of paediatric patients affected by primary cutaneous lymphoma. We also provided the Paediatric Primary Cutaneous Lymphoma Atlas that illustrates the clinicopathological spectrum of observed presentations, in the hope of supporting other physicians in the diagnostic process.

METHODS

Retrospective chart review of paediatric patients diagnosed with primary cutaneous lymphomas between 1980 and 2022 at the Paediatric Dermatology Unit of Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.

RESULTS

A total of 101 patients (58 males, 43 females) met the inclusion criteria. The most common subtypes were lymphomatoid papulosis (n = 48) and mycosis fungoides (n = 31). These were followed by primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorders (n = 7), primary cutaneous anaplastic large-cell lymphomas (n = 5), primary cutaneous marginal zone B-cell lymphomas (n = 3), primary cutaneous follicle centre lymphomas (n = 2), subcutaneous panniculitis-like T-cell lymphomas (n = 2), primary cutaneous peripheral T-cell lymphoma not otherwise specified (n = 1), primary cutaneous precursor B-lymphoblastic lymphoma (n = 1) and Sézary syndrome (n = 1). Clinical follow-up data covering a median of 70.8 months (range 1-324) were available for 74 patients, of whom three died due to cutaneous lymphoma.

CONCLUSIONS

Our findings shed light on the peculiar aspects and long-term outcomes of paediatric cutaneous lymphomas, particularly emphasizing their distinctive features in comparison to their adult counterparts and exploring the less common subtypes. Further larger-scale studies are warranted to better characterize these entities and to achieve a more rapid and accurate diagnosis.

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.

Primary Cutaneous Follicle Center Lymphoma Presenting as a Solitary Nodule on the Forearm of an Adolescent Girl: A Case Report and Literature Review

Primary cutaneous B-cell lymphomas (PCBCLs) are very rare to be seen in pediatric and adolescent age group, especially primary cutaneous follicle center lymphoma (PCFCL) which is considered the least occurring main subtype. Here, we describe a 16-year-old girl who developed a slowly growing solitary firm smooth surfaced erythematous nodule over her forearm. Histopathological examination showed a dense dermal nodular, periadnexal and perivascular lymphoid infiltrate extending deep to the subcutis. Immunohistochemical staining showed a B-cell population with positivity for CD20, variable staining for BCL6 and CD10 and uniquely staining for BCL2. Although a primary cutaneous marginal zone lymphoma (PCMZL) was considered but the presences of interfollicular BCL6 and CD10 positivity established the diagnosis of PCFCL. To our knowledge, only 12 cases of pediatric and adolescent PCFCL have been described in the literature.

Two Histologic Patterns of Lymphomatoid Papulosis Occurring in a Child: A Matter of Timing?

There are several histologic patterns seen in lymphomatoid papulosis, with the possibility of different subtypes occurring in the same patient. We report a case of lymphomatoid papulosis presenting with 2 histologic subtypes (types A and B) occurring concomitantly in a 10-year-old child, and postulate that the different subtypes occur dependent on the age of the lesion biopsied. Incidentally, one of the biopsies also shows a rarely seen pattern of pseudoepitheliomatous hyperplasia in a pediatric lymphomatoid papulosis patient.

Pediatric Cutaneous Hematologic Disorders: Cutaneous Lymphoma and Leukemia Cutis: Experience of a Tertiary-Care Pediatric Institution and Review of the Literature

BACKGROUND

Cutaneous hematologic malignancies are rare in children, and the literature about them is still sparse.

OBJECTIVE

The purpose of our study was to report our experience with pediatric cases of cutaneous hematologic disorders and describe their clinical and histological features.

METHODS

Data were retrospectively collected from the histopathologic database of the CHU Sainte-Justine, University of Montreal, Montreal, Canada. All patients up to 18 years of age with a diagnosis of a primary cutaneous lymphoma (including lymphomatoid papulosis), secondary cutaneous lymphoma or cutaneous manifestations of leukemia, followed from 1980 to 2019 at our center were reviewed.

RESULTS

Thirty-six patients were included. Age at presentation ranged from birth to 18 years of age (mean 7.83 ± 5.16; median 7.0). Ten different hematologic disorders were identified according to the WHO-EORTC classifications: lymphomatoid papulosis (10 cases), mycosis fungoides (6 cases), anaplastic large cell lymphoma (4 cases), pre-B acute lymphoid leukemia (5 cases), primary cutaneous marginal zone B-cell lymphoma (4 cases), primary cutaneous CD4⁺medium T-cell lymphoproliferative disorder (1 case), extranodal NK/T-cell lymphoma (1 case), hydroa vacciniforme-like lymphoproliferative disorder (1 case), B-cell lymphoblastic lymphoma (1 case) and acute myeloid leukemia (3 cases).

CONCLUSION

The most common subtype of cutaneous hematologic disease in our single institution study was lymphomatoid papulosis (type A and type C), followed by mycosis fungoides. Recognition of this large clinical and histological spectrum by dermatologists is important because diagnosis is often established by biopsy of skin lesions, even in secondary cutaneous cases. Moreover, the clinicopathological correlation is of utmost importance for the final diagnosis of those pathologies.

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.

Primary cutaneous T-cell lymphomas in childhood and adolescence

Primary cutaneous lymphomas are extranodal non-Hodgkin lymphomas of T- or B- cell origin, that predominantly affect older patients but have been reported in all age groups and as early as in the first years of life. Diagnosis of cutaneous lymphomas is challenging and requires high clinical suspicion and close collaboration between dermatologists, pediatric oncologists and pathologists. Skin involvement of non-Hodgkin lymphomas in children or adolescents can either be primary cutaneous or secondary due to an underlying nodal lymphoma. The most common primary cutaneous lymphomas encountered in children are of T-cell origin, with mycosis fungoides being the most prevalent cutaneous T-cell lymphoma, followed by CD30⁺ lymphoproliferative disorders. While cutaneous lymphomas share clinicopathologic characteristics between juvenile and adult forms, there are important differences in terms of clinical presentation, diagnosis and treatment. The hypopigmented variant of mycosis fungoides seems to be overrepresented in the pediatric age group. Prognosis and treatment of mycosis fungoides are stage dependent. The majority of children present with early-stage disease and respond well to topical corticosteroids and phototherapy.

Primary Cutaneous B-Cell Lymphomas in Children and Adolescents: A SEER Population-Based Study

BACKGROUND

Although primary cutaneous B-cell lymphomas (PCBCL) comprise 25% of all cutaneous lymphomas, their incidence in the pediatric population is unknown, and the information on pediatric PCBCL has mostly been gathered from individual case reports or series from single centers.

PATIENTS AND METHODS

This was a population-based, retrospective cohort study of patients in 18 cancer registries in the United States diagnosed between 2000 to 2016 through the Surveillance, Epidemiology, and End Results (SEER) program. Age-adjusted incidence rates were calculated for PCBCL in pediatric (<20 years) and adult (≥20 years) populations. Demographic, clinical, and pathological characteristics of PCBCL were compared between the two groups.

RESULTS

A total of 48 pediatric and 5128 adult PCBCL cases were included. Median age at diagnosis was 16.5 years and 65 years in the two groups, respectively. The major histologic subtypes of pediatric cases were marginal zone lymphoma (77.1%), followed by diffuse large B-cell lymphoma (12.5%) and follicle center lymphoma (10.4%), which were equally distributed in adults. The age-adjusted pediatric PCBCL incidence rate (per 1,000,000 person-years) was 0.12 (95% CI 0.09-0.16). The incidence in the adult population was approximately 40-fold higher than the one observed in the pediatric group (IRR 41.4, 95% CI 31.2-56.2). All 48 pediatric cases were alive during a median follow-up time of 48 months.

CONCLUSIONS

Pediatric PCBCL is a very rare disease affecting mostly adolescents of both sexes. The major histologic subtype is marginal zone lymphoma, and the prognosis is favorable.

Clinical characteristics and long-term outcome of 223 patients with mycosis fungoides at a single tertiary center in Korea: A 29-year review

BACKGROUND

Data regarding Asian patients with mycosis fungoides (MF) are limited.

OBJECTIVE

We aimed to investigate the clinical profile and long-term outcomes of patients with MF in Korea.

METHODS

A retrospective review of 223 patients with MF who were followed up for more than 6 months or died of MF within 6 months of diagnosis was performed.

RESULTS

Approximately 96.4% and 3.6% of the patients had an early stage and advanced stage, respectively. The mean age at diagnosis was 44.8 years. The mean duration of symptoms before diagnosis was 47.0 months. Various subtypes were noted, including mycosis fungoides palmaris et plantaris (21.5%), folliculotropic (8.5%), pityriasis lichenoides-like (6.7%), ichthyosiform (4.0%), lichenoid purpura-like (2.7%), and hypopigmented (2.2%) MF. Juvenile patients accounted for 16.6%. The higher the skin T stage, the poorer the response to treatment. The 10-year overall survival was 96.8% in early-stage patients and 25.0% in advanced-stage patients. General prognosis was favorable, while recurrence and subtype switching were seen in 29.4% and 2.7% of patients, respectively.

LIMITATIONS

Our patients may not represent all Korean patients with MF.

CONCLUSION

MF in Korea has a high proportion of variants, a younger age at onset, and favorable prognosis. A high index of suspicion and skin biopsy are needed for early diagnosis.

Primary cutaneous follicle center lymphoma in a 16-year-old girl

In the pediatric and adolescent age group, primary cutaneous lymphomas are rare, especially cutaneous B-cell lymphomas. According to the World Health Organization, the three main subtypes of primary cutaneous B-cell lymphomas are primary cutaneous marginal zone B-cell lymphoma (PCMZL), primary cutaneous follicle center lymphoma (PCFCL), and primary cutaneous diffuse large B-cell lymphoma, leg type. We present an extraordinary case of PCFCL arising in a 16-year-old female, only the sixth case of PCFCL to be reported in the literature in a patient less than 20 years old. Although PCMZL was considered in this case, the finding of lambda light chain restriction in the BCL-6 and CD10 positive population of lymphocytes established the diagnosis of primary cutaneous follicle center lymphoma. Not many data currently exist on the prognosis of PCFCL in young individuals, but adult PCFCL has a good prognosis with an indolent course and 5-year survival rates over 95%. Because of its uncommon manifestation in young patients, the diagnosis of PCFCL is often delayed or missed. This case is presented to raise awareness of PCFCL in the pediatric/ adolescent population and to contribute to the ongoing research of this condition.

Primär kutane T‐Zell‐Lymphome im Kindes‐ und Jugendalter

Primär kutane Lymphome sind extranodale T- oder B-Zell-Non-Hodgkin-Lymphome, die vorwiegend ältere Patienten betreffen, aber in allen Altersgruppen einschließlich der ersten Lebensjahre auftreten können. Die Diagnose kutaner Lymphome ist eine Herausforderung und erfordert einen hohen klinischen Verdacht sowie enge Zusammenarbeit zwischen Dermatologen, pädiatrischen Onkologen und Pathologen. Generell müssen primär kutane Lymphome von sekundär kutanen Lymphomen, welche meist von nodalen oder extranodalen Lymphomen ausgehen, unterschieden werden. Die häufigsten primär kutanen Lymphome im Kindesalter sind T-Zell Lymphome, wobei Mycosis fungoides das häufigste kutane T-Zell-Lymphom darstellt, gefolgt von CD30+ lymphoproliferativen Erkrankungen. Während klinisch-pathologische Merkmale kutaner Lymphome bei Jugendlichen und Erwachsenen ähnlich sind, gibt es wichtige Unterschiede bezüglich klinischer Präsentation, Diagnose und Behandlung. Die hypopigmentierte Variante der Mycosis fungoides scheint in der pädiatrischen Altersgruppe überrepräsentiert zu sein. Prognose und Behandlung der Mycosis fungoides sind stadienabhängig. Die Mehrheit der Kinder weist ein frühes Krankheitsstadium auf und spricht gut auf topische Kortikosteroide und Phototherapie an.

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.

Chronic Ulcers and Malnutrition in an African Patient

An 11-year-old girl with a congenitally malformed left hand, sickle cell trait, asthma, and history of appendicitis was transferred from Zambia for evaluation and treatment of widespread suppurative and ulcerative skin lesions that typically appeared after trauma to her skin. The ulcers first presented 3 years earlier but had markedly worsened in the 9 months before transfer, spreading circumferentially on her extremities and abdomen at the site of an appendectomy. They were painful and did not resolve with multiple courses of intravenous antibiotics and close management by a pediatric infectious disease specialist working for a nongovernmental organization (NGO) in her home country. Per NGO records, she had previously been  average weight-for-age. On presentation after international transfer, she was severely malnourished, with lesions covering ∼35% of her body. In initial workup, leukocytosis of 21 × 103 cells per μL (79% neutrophils), hemoglobin of 6.1 g/dL, and mean corpuscular volume of 66 fL were found. Iron studies revealed an iron level of 18 μg/dL, ferritin level of 55 ng/mL, total iron binding capacity of 222 μg/dL, and transferrin saturation of 8%. Inflammatory markers were elevated, C-reactive protein was 20.1 mg/dL, and the erythrocyte sedimentation rate was 131 mm/h. A chest computed tomography scan revealed bilateral pulmonary nodules, the largest in her left upper lobe measuring 2.4 × 2.0 × 1.9 cm. Our panel of experts reviews the evaluation and treatment of this patient with extensive suppurative and ulcerative skin lesions and the factors considered in offering charity care to international patients.

How I Diagnose Primary Cutaneous Marginal Zone Lymphoma

OBJECTIVES

Primary cutaneous marginal zone lymphoma (PCMZL) is 1 of the 3 major subtypes of primary cutaneous B-cell lymphoma. The diagnosis of PCMZL may be challenging, as the differential diagnosis includes benign cutaneous lymphoproliferations as well as other primary or secondary cutaneous B-cell or T-cell lymphomas. This review describes our approach to the diagnosis of PCMZL.

METHODS

Two cases are presented that illustrate how we diagnose each of the 2 subtypes of PCMZL. The clinicopathologic features of PCMZL and the ways in which these cases can be distinguished from both benign and other neoplastic entities are emphasized.

RESULTS

A definitive diagnosis of PCMZL requires the incorporation of histologic and immunophenotypic features, molecular genetic studies in some cases, and just as importantly, clinical findings. Emerging data suggest that the heavy chain class-switched cases may be more like a clonal chronic lymphoproliferative disorder.

CONCLUSIONS

The 2 subtypes of PCMZL create different diagnostic challenges and require the use of a multiparameter approach. Although very indolent, it is important to distinguish PCMZLs from reactive proliferations, because they frequently recur and may require antineoplastic therapies. It is also critical to distinguish PCMZLs from other B- or T-cell lymphomas so that patients are properly evaluated and not overtreated.

A Systematic Approach to the Cutaneous Lymphoid Infiltrates: A Clinical, Morphologic, and Immunophenotypic Evaluation

CONTEXT.—

The evaluation of cutaneous lymphoid infiltrates, both neoplastic and inflammatory, occurs very frequently in routine dermatopathologic examination and consultation practices. The "tough" cutaneous lymphoid infiltrate is feared by many pathologists; skin biopsies are relatively small, whereas diagnostic possibilities are relatively broad. It is true that cutaneous lymphomas can be difficult to diagnose and that in many circumstances multiple biopsies are required to establish a correct diagnostic interpretation. As a reminder, one should understand that low-grade cutaneous lymphomas are indolent disorders that usually linger for decades and that therapy does not result in disease cure. It is also important to remember that in most circumstances, those patients will die from another process that is completely unrelated to a diagnosis of skin lymphoma (even in the absence of specific therapy).

OBJECTIVE.—

To use a clinicopathologic, immunophenotypic, and molecular approach in the evaluation of common lymphocytic infiltrates.

DATA SOURCES.—

An in-depth analysis of updated literature in the field of cutaneous lymphomas was done, with particular emphasis on updated terminology from the most recent World Health Organization classification of skin and hematologic tumors.

CONCLUSIONS.—

A diagnosis of cutaneous lymphoid infiltrates can be adequately approached using a systematic scheme following the proposed ABCDE system. Overall, cutaneous T- and B-cell lymphomas are rare and "reactive" infiltrates are more common. Evaluation of lymphoid proliferations should start with a good sense of knowledge of the clinical presentation of the lesions, the clinical differential considerations, and a conscientious and appropriate use of immunohistochemistry and molecular tools.

Photo-photochemotherapy in Juvenile-onset Mycosis Fungoides: A Retrospective Study on 9 Patients

Mycosis fungoides (MF) is a rare disease and is considered the most common form of cutaneous T-cell lymphoma. Given the infrequent incidence of MF in patients under the age of 20, there are no established guidelines for the treatment of these patients; the overwhelming majority have an early-stage disease and progression to more advanced stages is very rare. This study presents the safety and effectiveness of photo-photochemotherapy as a first-line approach in the treatment of an early-stage MF even in young patients.

Cutaneous Hematolymphoid and Histiocytic Proliferations in Children

This article focuses on cutaneous hematopoietic neoplasms that are more likely to be encountered in the pediatric age-group and includes both lymphoproliferative and histiocytic disorders. The cutaneous hematologic disorders in children have a different epidemiologic profile to what is seen during adulthood. Although mycosis fungoides is the most frequent form of cutaneous lymphoma in adults, it is very rare in children. Because lymphoblastic leukemias and lymphomas are more frequent in the pediatric setting, cutaneous leukemic infiltrates are relatively common in this age-group. Similarly, histiocytic disorders are more common in children, particularly Langerhans cell histiocytosis and juvenile xanthogranuloma. Notably, the histiocytic disorders have undergone significant modifications on their nomenclature in the basis of the molecular characteristics that are present in them. A summary of the most frequent cutaneous hematopoietic disorders in children will be discussed further in this review.

Primary Cutaneous B-cell Lymphomas

B-cell lymphomas represent approximately 20% to 25% of primary cutaneous lymphomas. Within this group, most cases (>99%) are encompassed by 3 diagnostic entities: primary cutaneous marginal zone lymphoma, primary cutaneous follicle center lymphoma, and primary cutaneous diffuse large B-cell lymphoma, leg type. In this article, the authors present clinical, histopathologic, immunophenotypic, and molecular features of each of these entities and briefly discuss the rarer intravascular large B-cell lymphoma.

T-cell Lymphoma Epidemiology: the Known and Unknown

T-cell lymphoma, a collection of subtypes of Non-Hodgkin lymphoma, is a rare malignancy. The low prevalence of this disease has made it challenging to identify subtype-specific risk factors. Potential risk factors could enable us to identify high-risk patients and predict patient outcomes. Here, we report on the current epidemiologic and prognostic factors data associated with the individual subtypes both of peripheral T-cell lymphoma (PTCL) and cutaneous T-cell lymphoma (CTCL) found in large cohort and case studies. Additionally, with recent findings, as well as updates in the new World Health Organization (WHO) classification of lymphoid neoplasms, we consider what this could do to change our approach to this group of diseases.

Clinical Outcome and Prognosis of Young Patients with Mycosis Fungoides

BACKGROUND/OBJECTIVES

Mycosis fungoides (MF) in young patients is rare and may have atypical presentations. There are limited data in these patients. The objective was to determine the clinical outcome and prognosis of young patients with MF.

METHODS

A search of our institutional cancer registry database was conducted for patients diagnosed with MF at younger than 30 years of age.

RESULTS

Our study included 74 patients (median age at diagnosis 25.5 yrs). Sixty-five (88%) presented with early stage disease and variants of MF (n = 44 [59%]), leading to a median delay in diagnosis of 2.5 years. Hypopigmented MF (n = 27 [36.5%]) was the most common variant, affecting predominantly African American (44.4% vs 19%; p = 0.02) and younger (20 vs 26 yrs; p < 0.001) patients. All patients with hypopigmented MF presented with early stage disease and were less likely to develop progressive disease (PD) than those with other variants (11% vs 34%; p = 0.03). Nineteen patients (26%) developed PD during a median follow-up of 3.5 years, which was associated with advanced-stage disease (89% vs 17%; p < 0.001), older age (>20 yrs) (31% vs 13%; p = 0.08), African American race (52.6% vs 20%; p = 0.009), and poikilodermatous presentation (p < 0.01). Overall survival was good (97.2% at 5 yrs, 95.9% at 10 yrs) despite the delay in diagnosis and atypical presentation.

CONCLUSIONS

Progressive disease is associated with older age, African American race, the poikilodermatous variant, and advanced-stage disease. The hypopigmented variant is a common presentation in young patients and has an indolent disease course. Our study confirms an overall favorable prognosis in young patients with MF.

Primary cutaneous B-cell lymphomas with large cell predominance-primary cutaneous follicle center lymphoma, diffuse large B-cell lymphoma, leg type and intravascular large B-cell lymphoma

In this review, we present clinical features and detailed histopathologic, immunologic, and molecular information regarding primary cutaneous follicle center lymphoma and primary cutaneous diffuse large B-cell lymphoma, leg type which together represent two of the three most common types of primary cutaneous B-cell lymphoma recognized in the current WHO classification system.^1,2 Overall, B-cell lymphomas represent 19-27% of primary cutaneous lymphomas in most large European and American studies^3-6 and together, primary cutaneous follicle center lymphoma and primary cutaneous diffuse large B-cell lymphoma, leg type account for approximately 2/3 to ¾ of these cases.^5,7-11 Both subtypes can contain a high content of large B-lymphocytes, although most cases of primary cutaneous follicle center lymphomas exhibit a range in cell size and cytology. Intravascular large B-cell lymphoma, a less commonly-encountered EBV-negative primary cutaneous B-cell lymphoma composed of large cells, will be more briefly discussed in this report as well.

Primary Cutaneous Lymphomas in Children and Adolescents

Primary cutaneous lymphomas are rare in children and mostly represented by mycosis fungoides and CD30(+) lymphoproliferative disorders. Most pediatric cutaneous lymphomas have similar clinical/pathological features as their adult counterparts, particularly the T-cell subtypes. With regard to outcome, adult cutaneous mature T-cell lymphomas have a tendency to progression, while this appears to be relatively infrequent in children. The outcome of cutaneous B-cell lymphomas depends on subtype, with the B-lymphoblastic entity being associated with similar outcomes to precursor B acute lymphoblastic leukemia, while there are insufficient data on other entities. The diagnosis and treatment of these patients require a close collaboration between experienced pediatric pathologists, dermatologists, and oncologists. Prospective collection of longitudinal clinical and biological data from children with these rare lymphomas is needed to better understand their biological and clinical behavior and to ultimately discover the best therapeutic strategies.

Sézary Syndrome in a 17-Year-Old Boy: Clinicopathologic Features and Genomic Profile

We describe the case of a 17-year-old Hispanic boy who had had erythroderma and diffuse lymphadenopathy for approximately 6 months. A diagnosis of Sézary syndrome was made on the basis of the histologic features of the skin; the presence of the same T-cell clone on the skin, blood, and bone marrow; and the high CD4(+) lymphocyte count with an aberrant phenotype in peripheral blood; bone marrow involvement was also present. The patient was treated with systemic gemcitabine and achieved partial remission.

Lymphomatoid Papulosis in Children and Adolescents: A Systematic Review

BACKGROUND

Lymphomatoid papulosis (LyP) is a lymphoproliferative disorder that is rare among adults and even rarer among children. In adults, LyP is associated with an increased risk of secondary lymphomas.

OBJECTIVE

The aim of this systematic review was to describe the clinical and histopathological features of LyP in children, to assess the risk of associated lymphomas, and to compare the disease to the adult form.

METHODS

A systematic review was conducted using the MEDLINE (PubMed), EMBASE, Scopus, and Cochrane databases from inception to June 2015. Articles were included if data were extractable from studies, case series, and single reports of pediatric LyP patients.

RESULTS

A total of 251 children and adolescents with LyP were identified, with the mean age at diagnosis being 9.3 ± 4.6 years (n = 187). The female to male ratio was 1:1.4, and the majority of children reported on were Caucasian (n = 74, 85.1 %). The predominant histologic subtype was type A (n = 106, 79.1 %). Clinically, LyP lesions presented as erythematous papules or nodules, appearing preferentially on the extremities and the trunk. LyP has to be differentiated from pityriasis lichenoides (PL) and primary cutaneous anaplastic large cell lymphoma (ALCL). PL and associated lymphomas were diagnosed before, with, and after LyP in 19 and 14 cases, respectively. Of the 14 subjects with associated lymphomas, two children developed systemic ALCL.

CONCLUSION

LyP has to be differentiated from ALCL to avoid erroneous treatments. Due to the increased risk of development of non-Hodgkin lymphomas, lifelong follow-up and proper patient counseling are warranted.