Langerhans cell histiocytosis of the skin

MUM1/IRF4 immunolabeling of neoplastic Langerhans histiocytes in a putative case of canine Langerhans cell histiocytosis

Langerhans cell histiocytosis is a systemic histiocytic proliferative disease with cutaneous manifestations which is well described in human medical literature and has relatively recently been reclassified as a neoplastic disorder. The diagnosis of canine Langerhans cell histiocytosis has been proposed in the veterinary literature to refer to a histiocytic proliferative disease in the dog with clinical and histopathologic features that mirror the human disease. However, reports that invoke this diagnosis are rare and often lack complete diagnostic characterization. This case report presents an extensive diagnostic investigation of a putative case of Langerhans cell histiocytosis in a 3-year-old male castrated Golden Retriever dog, including gross, cytologic, histopathologic, and immunohistochemical findings. Furthermore, we document that canine LCH may have positive immunolabeling for the transcription factor multiple myeloma oncogene 1/interferon regulatory factor 4 (MUM1/IRF4), which is classically used for the diagnosis of canine plasma cell neoplasms.

Langerhans Cell Histiocytosis Evolving into Juvenile Xanthogranuloma: Two Linked Entities

BACKGROUND

Langerhans cell histiocytosis (LCH) represents a myeloid clonal proliferation that involves the skin and other organs. Occasionally, cases of LCH evolve into juvenile xanthogranuloma (JXG).

CASE PRESENTATION

A 7-month-old boy presented with an itchy, flaky rash resembling seborrheic dermatitis affecting the scalp and eyebrows. The lesions started at 2 months old. On physical examination, there were reddish/brown lesions on the trunk, denuded areas on the groin and neck, and a large lesion behind his bottom teeth. In addition, there were thick white plaques in his mouth and thick whitish material in both ears. A skin biopsy showed features of LCH. Radiologic examination demonstrated several osteolytic lesions. Chemotherapy produced marked improvement. A few months later, the patient developed lesions with clinical and histologic features of XG.

CONCLUSION

A possible association between LCH and XG is explained by lineage maturation development. Chemotherapy may play a role in modifying the production of cytokines that enhance the transformation or 'maturation' of Langerhans cells into multinucleated macrophages (Touton cells) characteristic of a more favorable proliferative inflammatory condition.

Pustular lesions in the neonate: Focused diagnostic approach based on clinical clues

Pustules in a neonate can be due to various causes. Though the majority of conditions causing pustules in a neonate are benign, it is essential to clearly differentiate these from serious ones. A systematic approach based on detailed history and clinical examination of the neonate along with basic laboratory evaluation narrows down diagnostic possibilities and aids in the correct diagnosis. This review outlines a step-by-step approach so as to avoid clinical dilemmas and unnecessary intervention.

Survivorship Issues in Adult Patients With Histiocytic Neoplasms

Adult-onset histiocytoses (AOH), primarily Rosai-Dorfman disease (RDD), Erdheim-Chester Disease (ECD), and adult Langerhans cell histiocytosis (ALCH), are a group of related histiocytic neoplastic disorders featuring multisystemic manifestations. The disorders are largely incurable, and are essentially chronic neoplastic diseases with a variable prognosis. Prompt diagnosis and treatment is important to prevent debilitating and even life-threatening complications. Survivorship issues abound in AOH, due to their multisystemic manifestations and the sometimes recalcitrant chronic inflammation, which can lead to other debilitating complications such as fatigue, weakness, and pain. Because these disorders are rare, few healthcare professionals are proficient in their management; therefore the aim of these guidelines is to offer guidance on how to manage patients, and how to create survivorship care plans through the efforts of an interdisciplinary team.

Langerhans cell histiocytosis in an adult patient

Aim: to present a clinical case of a rare dermatosis — Langerhans cell histiocytosis (LCH) in an adult patient.

Materials and methods. A clinical and laboratory examination of a 64-year-old woman who had complained of rashes on the skin of the scalp, neck, trunk and lower extremities accompanied by itching was carried out. A histological study of skin biopsy samples from the lesion area, as well as an immunohistochemical study of Langerhans cell markers — langerin and S-100 protein — were performed.

Results. Clinical manifestations of the disease, the presence of histiocytic infiltrate in the epidermis and dermis during the histological study and immunohistochemical detection of langerin infiltrate cells and S-100 protein were all consistent with the diagnosis of LCH. The therapy with methotrexate subcutaneously significantly improved the patient’s condition.

Conclusion. Verification of the LCH diagnosis requires a histological study of skin biopsy samples and an immunohistochemical study of Langerhans cell markers. The efficacy of methotrexate in the treatment of this disease has been confirmed.

Systemic Histiocytosis (Langerhans Cell Histiocytosis, Erdheim-Chester Disease, Destombes-Rosai-Dorfman Disease): from Oncogenic Mutations to Inflammatory Disorders

PURPOSE OF REVIEW

Provide an overview of recent progress in decoding the pathogenesis and treatment of systemic histiocytoses.

RECENT FINDINGS

Advances in molecular techniques over the last few years, enabling the identification of several MAPK mutations in lesion histiocytes, have revolutionized our understanding of histiocytosis that led to a revised classification and new treatments. Since the 2010 discovery of the BRAF^V600E mutation in 57% of Langerhans cell histiocytosis (LCH) lesions, several other kinase mutations have been found, mostly in the MAPK pathway, and also in other key signaling pathways, in LCH, Erdheim-Chester Disease (ECD) and, less frequently, Destombes-Rosai-Dorfman disease (RDD). Those revolutionary breakthroughs enhanced our understanding of the pathogenesis of histiocytosis and led to trials with targeted therapies that demonstrated notable efficacy.

Langerhans Cell Histiocytosis With Clinical and Histologic Features of Hidradenitis Suppurativa: Brief Report and Review

Langerhans cell histiocytosis (LCH) is an uncommon histiocytic disorder in adults. Clinically, this rare entity can mimic other dermatologic conditions, including hidradenitis suppurativa. A case of LCH is reported with clinical and histologic features of hidradenitis suppurativa, along with a review of these unusual findings. Clinical dermatologists and dermatopathologists benefit from awareness of this unique presentation, which may prompt earlier identification and diagnosis of adult patients with LCH.

Outpatient dermatology consultation impacts the diagnosis and management of pediatric oncology patients: A retrospective study

BACKGROUND

The impact of dermatology consultation on the care of children with oncologic conditions is unknown.

OBJECTIVE

To review outpatient dermatology visits and the resulting impact on diagnosis and management of pediatric oncology patients.

METHOD

Retrospective review of pediatric oncology patients with outpatient dermatology visits at a tertiary care center from 2008 to 2015.

RESULTS

The most common dermatologic diagnoses in 516 patients were skin infections (21.3%) and nonmalignant skin eruptions (33.4%). A diagnosis of significant impact (ie, malignancy, adverse cutaneous drug reaction, graft-versus-host disease, varicella-zoster virus, or herpes simplex virus infection), was made at the dermatology clinic in 14.7% of visits. Consultation resulted in a change in diagnosis in 59.8% of patients, change in dermatologic management in 72.4% of patients, and change in management of noncutaneous issues in 12.4% of patients.

LIMITATIONS

The use of electronic medical records, the nongeneralizable study population, and the retrospective design represent potential limitations.

CONCLUSION

Outpatient dermatology consultation can affect the care of pediatric oncology patients with respect to diagnosis and treatment of skin conditions and management of nondermatologic issues.

[Adult Langerhans cell histiocytosis]

Langerhans cell histiocytosis (LCH) is a rare disease affecting both genders and can occur at any age. It often evolves through successive flares, and its severity varies from benign forms that don't require treatment to life threatening disease. Some patients have important functional impairment with psychological and social consequences and prolonged disability. LCH may affect only one organ, with uni- or multifocal involvement or be multisystem disease involving multiple organs. The organs most frequently involved are bones, lung, skin and the endocrinal system. Pulmonary LCH is strongly related to smoking. Some patients have mixed histocytosis combining LCH and other histiocytic disorders. The diagnosis relies on the histological study of tissues samples, and shows tissue infiltration with large cell with pale cytoplasm and reniform nucleus, staining for CD1a and Langerin (CD207) on immunohistochemistry. The BRAF^V600E mutation is observed in tissue samples in approximately half of patients and the activation of the RAS-RAF-MEK-ERK pathway has been shown to be constantly activated in LCH lesions, regardless the BRAF status. These findings represent an important forward step in the understanding of the physiopathology of the disease. Treatment must be adapted to the severity of the disease and goes from conservative observation to systemic chemotherapy. Therapies targeting the RAS-RAF-MEK-ERK pathway are promising treatments for progressive disease.

Langerhans cell histiocytosis: a comprehensive review

Langerhans cell histiocytosis (LCH) is currently regarded as a myeloid neoplasm, with remarkably broad clinical spectrum, ranging from isolated skin or bone lesions to a disseminated disease that can involve nearly any organ. LCH is generally regarded as a sporadic disease that occurs predominantly in the paediatric population. The diagnosis of LCH is confirmed by immunohistochemistry (IHC) by demonstrating the presence of dendritic cell markers such as S100 protein, in addition to CD1a and langerin. Contrary to previous beliefs, recent literature reveals that the pathogenesis of LCH might involve a clonal process implicating BRAF c.1799T>A (p.Val600Glu) and other mutations [(600DLAT) B-RAF and (T599A) B-RAF, somatic MAP2K1 mutations].Through this review article, we have summarised the latest understanding of the biological and salient histological characteristics of LCH and its potential morphological mimics.

Radiotherapy for Langerhans Cell Histiocytosis of Bilateral Eyelids

Langerhans cell histiocytosis (LCH) is a rare disorder with numerous clinicopathological variants with differing clinical courses, treatment methods, and prognoses. We report one patient with atypical LCH of the bilateral lower eyelids and subsequent successful treatment with local radiation therapy.

A different cause for respiratory disorder in children: cases with pulmonary Langerhans cell histiocytosis

BACKGROUND AND AIMS

In children, complaints of a respiratory disorder are very frequent. Etiology of respiratory illness is a broad spectrum that varies from a simple viral infection to a malignant disorder. Pulmonary Langerhans cell histiocytosis (PLCH) is one of these entities and it is truly rare in children. The aim of this study is to evaluate our patients with PLCH.

METHODS

Patients who had been diagnosed with PLCH were retrospectively evaluated. Features of medical history, onset of the complaints, date of the diagnosis, chest X-Ray and computed tomography (CT) findings, histopathology and other laboratory investigations were considered.

RESULTS

There were four cases with PLCH. All of them were male, ages were between 5 months and 16 years. In three cases, major complaints were chronic respiratory problems whereas in one of them there was acute respiratory distress beginning with cough and leading to pneumothorax. In all of the cases, multisystemic involvement was prominent. The diagnosis was proven by histopathology in all of the cases. In two children with smaller age, skin involvement was detected. Time from complaint to diagnosis was minimum 3 months and maximum 3 years.

CONCLUSION

PLCH is a rare disorder in children. Pulmonary involvement is generally a component of systemic involvement but in many cases it might have been detected with early respiratory complaints. So, children with chronic respiratory problems should be carefully evaluated and should be followed up for rare entities like PLCH.

A review of histiocytic diseases of dogs and cats

Histiocytic proliferative disorders are commonly observed in dogs and less often cats. Histiocytic disorders occur in most of the dendritic cell (DC) lineages. Canine cutaneous histiocytoma originates from Langerhans cells (LCs) indicated by expression of CD1a, CD11c/CD18, and E-cadherin. When histiocytomas occur as multiple lesions in skin with optional metastasis to lymph nodes and internal organs, the disease resembles cutaneous Langerhans cell histiocytosis of humans. Langerhans cell disorders do not occur in feline skin. Feline pulmonary LCH has been recognized as a cause of respiratory failure due to diffuse pulmonary infiltration by histiocytes, which express CD18 and E-cadherin and contain Birbeck's granules. In dogs and cats, histiocytic sarcomas (HS) arise from interstitial DCs that occur in most tissues of the body. Histiocytic sarcomas begin as localized lesions, which rapidly disseminate to many organs. Primary sites include spleen, lung, skin, brain (meninges), lymph node, bone marrow, and synovial tissues of limbs. An indolent form of localized HS, progressive histiocytosis, originates in the skin of cats. Hemophagocytic HS originates in splenic red pulp and bone marrow macrophages in dogs and cats. In dogs, histiocytes in hemophagocytic HS express CD11d/CD18, which is a leuko-integrin highly expressed by macrophages in splenic red pulp and bone marrow. Canine reactive histiocytic diseases, systemic histiocytosis (SH) and cutaneous histiocytosis, are complex inflammatory diseases with underlying immune dysregulation. The lesions are dominated by activated interstitial DCs and lymphocytes, which invade vessel walls and extend as vasocentric infiltrates in skin, lymph nodes, and internal organs (SH).

Neonatal leukaemia cutis

Neonatal leukaemia cutis is a significant neoplasm that may represent a cutaneous manifestation of systemic leukaemia, usually of myeloblastic type. Rarely, it may be or appear to be limited to skin, in which case it is called neonatal aleukaemic leukaemia cutis. By definition, it presents within the first 4 weeks of life and often has a 'blueberry muffin baby' appearance of magenta coloured nodules affecting almost any area of the skin, usually sparing mucous membranes, palms and soles. This clinical pattern is more commonly associated with neonatal infections such rubella and toxoplasmosis, and may be evident with other neonatal neoplasms such as neuroblastoma. Due to the morbidity associated with chemotherapy and reported cases of spontaneous remission without systemic progression in those with neonatal aleukaemic leukaemia cutis without 11q23 translocation, the authors not treating the child with chemotherapy, but to simply monitor for fading of the violaceous nodules, and watch for possible signs of systemic leukaemia.

Clinicopathologic characteristics and outcomes of histiocytic and dendritic cell neoplasms: the moffitt cancer center experience over the last twenty five years

Neoplasms of histiocytic and dendritic cells are rare disorders of the lymph node and soft tissues. Because of this rarity, the corresponding biology, prognosis and terminologies are still being better defined and hence historically, these disorders pose clinical and diagnostic challenges. These disorders include Langerhans cell histiocytosis (LCH), histiocytic sarcoma (HS), follicular dendritic cell sarcoma (FDCS), interdigtating cell sarcoma (IDCS), indeterminate cell sarcoma (INDCS), and fibroblastic reticular cell tumors (FRCT). In order to gain a better understanding of the biology, diagnosis, and treatment in these rare disorders we reviewed our cases of these neoplasms over the last twenty five years and the pertinent literature in each of these rare neoplasms. Cases of histiocytic and dendritic cell neoplasms diagnosed between 1989–2014 were identified using our institutional database. Thirty two cases were included in this analysis and were comprised of the following: Langerhans cell histiocytosis (20/32), histiocytic sarcoma (6/32), follicular dendritic cell sarcoma (2/32), interdigitating dendritic cell sarcoma (2/32), indeterminate dendritic cell sarcoma (1/32), and fibroblastic reticular cell tumor (1/32). Median overall survival was not reached in cases with LCH and showed 52 months in cases with HS, 12 months in cases with FDCS, 58 months in cases with IDCS, 13 months in the case of INDCS, and 51 months in the case of FRCT. The majority of patients had surgical resection as initial treatment (n = 18). Five patients had recurrent disease. We conclude that histiocytic and dendritic cell neoplasms are very rare and perplexing disorders that should be diagnosed with a combination of judicious morphology review and a battery of immunohistochemistry to rule out mimics such as carcinoma, lymphoma, neuroendocrine tumors and to better sub-classify these difficult to diagnose lesions. The mainstay of treatment for localized disease remains surgical resection and the role of adjuvant therapy is unclear. In patients with multiple areas of involvement, treatment at tertiary care centers with multimodality treatment is likely needed. Accurate subset diagnosis will contribute to better data as well as treatment outcomes analysis of these rare disorders of adult patients in the future.

Differentiating skin-limited and multisystem Langerhans cell histiocytosis

OBJECTIVE

To identify features associated with multisystem involvement and therapeutic failure in patients with skin Langerhans cell histiocytosis (LCH).

STUDY DESIGN

We reviewed medical records of 71 consecutive patients with LCH with skin involvement evaluated at Texas Children's Hospital and analyzed clinical features, laboratory results, and the presence of circulating cells with the BRAF-V600E mutation with respect to initial staging and clinical outcomes.

RESULTS

Skin disease in patients older than 18 months of age at diagnosis was associated with the presence of multisystem disease (OR, 9.65; 95% CI, 1.17-79.4). Forty percent of patients referred for presumed skin-limited LCH had underlying multisystem involvement, one-half of these with risk-organ involvement. Patients with skin-limited LCH had a 3-year progression-free survival of 89% after initial therapy, and none developed multisystem disease. Patients with skin/multisystem involvement had a 3-year progression-free survival of 44% with vinblastine/prednisone therapy, and risk-organ involvement did not correlate with failure to achieve nonactive disease. Circulating cells with BRAF-V600E were detected at higher frequency in patients with multisystem involvement (8 of 11 skin/multisystem vs 1 of 13 skin-limited; P = .002).

CONCLUSION

Skin-limited LCH necessitates infrequent therapeutic intervention and has a lower risk of progression relative to skin plus multisystem LCH. The less-aggressive clinical course and lack of circulating cells with the BRAF-V600E mutation in skin-limited LCH suggest a different mechanism of disease origin compared with multisystem or risk-organ disease.

Consensus guidelines for the diagnosis and clinical management of Erdheim-Chester disease

Erdheim-Chester disease (ECD) is a rare, non-Langerhans histiocytosis. Recent findings suggest that ECD is a clonal disorder, marked by recurrent BRAFV600E mutations in >50% of patients, in which chronic uncontrolled inflammation is an important mediator of disease pathogenesis. Although ∼500 to 550 cases have been described in the literature to date, increased physician awareness has driven a dramatic increase in ECD diagnoses over the last decade. ECD frequently involves multiple organ systems and has historically lacked effective therapies. Given the protean clinical manifestations and the lack of a consensus-derived approach for the management of ECD, we provide here the first multidisciplinary consensus guidelines for the clinical management of ECD. These recommendations were outlined at the First International Medical Symposium for ECD, comprised of a comprehensive group of international academicians with expertise in the pathophysiology and therapy of ECD. Detailed recommendations on the initial clinical, laboratory, and radiographic assessment of ECD patients are presented in addition to treatment recommendations based on critical appraisal of the literature and clinical experience. These formalized consensus descriptions will hopefully facilitate ongoing and future research efforts in this disorder.

Cutaneous Langerhans cell histiocytosis: study of Asian children shows good overall prognosis

AIM

To describe an Asian population with isolated cutaneous Langerhans cell histiocytosis (LCH), presenting a review on previous studies on this subgroup of patients and comparing our cohort with other studies of cutaneous LCH with systemic involvement.

METHODS

All patients diagnosed as LCH with cutaneous involvement presenting to a tertiary paediatric hospital (KK Women's & Children's Hospital) between January 2001 and December 2011 were reviewed. Information recorded included clinical presentation, investigation results, treatment and outcome.

RESULTS

We identified 10 patients with cutaneous manifestations of LCH. Six had isolated cutaneous LCH with no visceral or bony involvement, while four had cutaneous lesions with involvement of other organ systems. Of the patients with isolated skin involvement, three were treated with surgical excision, one with topical corticosteroids and two with multi-agent chemotherapy. The four patients with concomitant systemic involvement were treated with multi-agent chemotherapy. None of our patients with isolated cutaneous LCH progressed to multisystem disease during the follow-up period.

CONCLUSION

Cutaneous LCH, with or without other organ involvement at diagnosis has a good overall prognosis. However, long-term follow-up is recommended in view of possible recurrence.

Langerhans cell histiocytosis: a retrospective analysis in a Korean tertiary hospital from 2003 to 2012

Epidemiological study of Langerhans cell histiocytosis (LCH) has been limited due to its rarity and multisystemic involvement. The aim of this study was to investigate the epidemiological features of LCH via the clinical data warehouse (CDW). Clinical data of 30 LCH patients from the all departments of a tertiary referral hospital between 2003 and 2012 were analyzed retrospectively by searching the CDW. The male-to-female ratio was 2.8:1. The age of onset ranged 7 days to 57 years with a median of 13 years. Of the patients, 36.7% presented initial symptoms before the age of 10 years. The involved organs at diagnosis were: bone (66.7%), skin (16.7%), lungs (13.3%) and lymph node (3.3%). For all of the 30 cases, there were 31 disease sites because of a single case of multisystemic disease involving both skin and bone. Of the 96.7% of patients with single-system disease, 69.0% had bony involvement. This study elucidated the clinical features of LCH from all the departments of a tertiary hospital via the CDW, which suggests a potential role of the CDW as a new epidemiological approach for rare diseases.

Langerhans cell histiocytosis first presenting in the skin in adults: frequent association with a second haematological malignancy

BACKGROUND

Langerhans cell histiocytosis (LCH) in adults first presenting in the skin is rare. Guidelines for staging, treatment and follow-up are lacking.

OBJECTIVES

To better define staging procedures, treatment results and clinical course in adult patients with LCH first presenting in the skin.

METHODS

Eighteen adult patients with LCH first presenting in the skin were collected from five centres collaborating in the Dutch Cutaneous Lymphoma Group. Clinical records and (skin) biopsy specimens were reviewed and follow-up data were obtained. A literature search on adult patients with LCH presenting in the skin was performed.

RESULTS

Staging procedures showed extracutaneous disease in three of 16 patients who were adequately staged. One patient had a histologically confirmed lytic LCH bone lesion, while two patients had a myelodysplastic syndrome. During follow-up two of 18 patients developed extracutaneous localizations of LCH. Five patients developed a second haematological malignancy, including (myelo)monocytic leukaemia (two cases), histiocytic sarcoma (one case), diffuse large B-cell lymphoma (one case) and peripheral T-cell lymphoma (one case). Review of the literature revealed six other adult patients with a second haematological malignancy preceding or following a diagnosis of LCH.

CONCLUSIONS

The results of the present study suggest an increased risk of a second haematological malignancy in adult patients with LCH presenting in the skin. Extensive staging at presentation and long-term follow-up are therefore warranted in such patients.

Congenital self healing reticulohistiocytosis in a newborn (Hashimoto Pritzker)

Congenital self-healing reticulohistiocytosis is the benign spectrum of Langerhans Cell Histiocytosis, characterized by cutaneous lesions at birth or in the neonatal period, absence of systemic manifestations and spontaneous resolution of clinical status. Despite the benign and often self-resolving course in most patients, studies show that in some cases there may be metastasis or recurrence of the disease, emphasizing that the clinical course is variable, requiring long-term follow-up. The monitoring of the patient for a long period is important to detect possible systemic involvement, as there is a report of recurrence involving the skin, mucosa, bone and pituitary gland.

Topical nitrogen mustard therapy in patients with Langerhans cell histiocytosis

BACKGROUND

Langerhans cell histiocytosis (LCH) is characterized by abnormal proliferation and infiltration of Langerhans cells in different organs. The skin is frequently involved either as unisystem or multisystem disease.

OBJECTIVES

To review the clinical response and side-effects of nitrogen mustard therapy in LCH in children and adults with unisystem or multisystem disease.

PATIENTS AND METHODS

This retrospective study includes 10 children and four adults with LCH, treated with nitrogen mustard from 1975 to 2010. The median extent of skin involvement was 46% (range 5-100%).

RESULTS

Overall, 13 patients had complete or partial response. Although eight patients achieved a complete response with a median time of 12·3months (range 36 days to 1·9 years), six of these patients ultimately relapsed. One patient, who had unisystem disease limited to the skin, initially showed progression of her cutaneous lesions with nitrogen mustard treatment. Although subsequently the cutaneous lesions completely regressed, concomitant systemic involvement was noted. Four other patients similarly experienced improvement of their skin lesions with treatment, but also exhibited progression of the LCH systemically. The patients were treated with other therapies prior and adjunctive to nitrogen mustard. However, five patients had progression to other organs, despite regression of skin lesions, which supports that the treatment effect in the skin is related to topical nitrogen mustard. Six patients developed contact dermatitis to nitrogen mustard.

CONCLUSIONS

Topical nitrogen mustard can be an effective and safe therapy in both children and adults with cutaneous LCH, although relapses are common.

Langerhans cell histiocytosis preceding the development of juvenile xanthogranuloma: a case and review of recent developments

Langerhans cell histiocytosis (LCH) and juvenile xanthogranuloma (JXG) both belong to the histiocytosis group of disorders, which have varied prognostic and clinical significance. Their normal cellular counterparts share a common CD34-positive hematopoietic stem cell precursor that matures along CD14-negative or -positive pathways. Rare cases of LCH and JXG show overlapping findings, suggesting that this divergent maturation is not irreversible. We report a case of an infant diagnosed with cutaneous LCH shortly after birth. Two years after diagnosis, a recurrent lesion in his external auditory canal contained lipidized cells with CD68 and factor XIIIa expression and lacked Birbeck granules and CD1a, consistent with JXG. Our case and previous reports of this phenomenon raise the question of a histogenic relationship between LCH and JXG, and we speculate that the lesional cells of origin are subjected to therapy-induced modulation that results in a varied differentiation.

Langerhans cell histiocytosis of the optic chiasm: case report

BACKGROUND AND IMPORTANCE

Langerhans cell histiocytosis (LCH) is an uncommon disease, usually affecting the cranium and peripheral bones. We present a rare case of isolated optic chiasm involvement by LCH to highlight the importance of considering LCH in the differential diagnosis of optic chiasm lesions.

CLINICAL PRESENTATION

A 71-year-old woman presented with a 6-week history of worsening peripheral vision, headaches, weakness, cold sensitivity, and fatigue. She was found to have dense bitemporal hemianopsia. Magnetic resonance imaging revealed a 2-cm lesion, contrast enhancing on T1 and bright on T2 signal, involving the optic chiasm but not the pituitary gland. Preoperative considerations included optic nerve glioma, choristoma of the stalk, sarcoid, hypothalamic glioma, and Langerhans cell histiocytosis. The patient underwent a right subfrontal craniotomy for biopsy of the lesion. The optic chiasm was grossly enlarged with no tissue external to the chiasm. A midline incision was made in the lamina terminalis, and multiple biopsies were taken of firm fibrous material. Histologically, the tumor was characteristic for LCH and included a mixture of histiocytes with features of Langerhans cells, eosinophils, small lymphocytes, macrophages, neutrophils, and plasma cells.

CONCLUSION

LCH is a rare disease, generally affecting bone, skin, lymph nodes, and in more severe cases, visceral organs. LCH involving the optic pathways is a rare condition that should be included in the differential for adults with mass lesions involving the orbit, eye, optic nerve, or chiasm. Future clinical and basic science research is needed to better understand LCH, its molecular origin, and its growth pattern.

Cutaneous manifestations of malignancy

PURPOSE OF REVIEW

Many types of cancer can cause lesions to appear on the skin. Cutaneous manifestations may be primary or secondary to an underlying malignancy. Skin lesions may appear prior to the onset of systemic malignancy or they may occur concurrently or following an established diagnosis. The purpose of this review is to educate medical providers about several types of pediatric malignancies that can present with cutaneous findings. The primary focus of this review will be cutaneous features of leukemias, lymphomas, neuroblastoma, some sarcomas, and Langerhans cell histiocytosis.

RECENT FINDINGS

A wide range of cutaneous manifestations have been reported in systemic malignancies of children. In addition to providing a description of more typical features of skin lesions associated with these conditions, this review will summarize a few recent case reports of pediatric malignancies with unusual cutaneous presentations.

SUMMARY

Systemic malignancy can present with a variety of cutaneous manifestations. Given that accurate, prompt diagnosis of malignancy can have tremendous prognostic significance, it is imperative that clinicians are familiar with features of skin lesions that may be seen in this setting.

Langerhans cell histiocytosis: old disease new treatment

Langerhans cell histiocytosis (LCH) has been previously thought of as a rare illness, but is now increasingly diagnosed as a result of the more intensive investigations of patients with cystic pulmonary disease. In recent years, treatments developed from our new understanding of the molecular biology of malignant disease have been applied to patients with LCH, and responses seen. In this review, we describe the origins, presentation and modern treatment of LCH, showing that there is new hope for patients with this condition.

[Case for diagnosis. Langerhans cell histiocytosis]

Langerhans cell histiocytosis is a rare disease of unknown cause, characterized by the proliferation of histiocytic cells (Langerhans cells). Its diagnosis is especially difficult due to its wide clinical spectrum, ranging from a single lesion to a multisystemic disorder. Diagnosis may be confirmed by means of an immunohistochemical study. Treatment depends upon the severity of the disease, and systemic chemotherapy may be needed.

Langerhans cell histiocytosis: Current concepts and treatments

Langerhans cell histiocytosis (LCH) is a rare proliferative disorder of cells with the phenotype of activated Langerhans cells. The diagnosis of LCH is often delayed or missed. Many questions about LCH remain to be answered, including whether it is caused by a malignancy or by immune dysregulation. Data from the early 1990s showed that LCH consisted of an accumulation of monoclonal LCH cells, suggesting a neoplastic disorder. However, further investigations with current sophisticated techniques have not shown consistent genomic aberrations. Recent data which suggests a role for an IL-17A dependant pathway of dendritic cell fusion in LCH remains to be proven. The most recent data taken together swing the pendulum towards an immunologic aberration. The clinical course of LCH is highly variable, ranging from a self-healing solitary bone lesion to widely disseminated life-threatening disease. Patients with multisystem (MS) disease with organ dysfunction, particularly those refractory to front line therapy, and those with multiple reactivations of disease associated with significant permanent sequelae represent the greatest challenge. Early switch of refractory patients to salvage therapies has contributed to the improvement in survival of MS-LCH patients. Due to the rarity of LCH in children and adults, patients must be enrolled on multi-national clinical trials, whenever possible, to advance our knowledge of the optimal therapeutic strategies and long-term outcomes.

Histiocytosis disorders in Northeast Egypt: epidemiology and survival studies (a 5-year study)

Histiocytosis disorders include a wide group of disorders characterized by monocytes, macrophages and dendritic cell infiltration of different tissues. There are few clinico-epidemiologic studies of such disease. Our study was designed to look at the clinico-epidemiological features and outcome of patients with histiocytosis disorders in Northeast Egypt. Twenty-seven cases with histiocytosis disorders accrued over a 5-year period were analyzed and classified as having unifocal, multifocal, or multisystem disease. They were 14 males and 13 females. Twenty-two patients representing 81.5% of cases were more than two years of age while 5 patients (18.5%) were less than 2 years. Lymphadenopathy was the commonest presentation (55.55%) followed by bone lesions (44.44%). Involvement was unifocal in 12, multifocal in 10, and multisystem in 5 cases. The histological features were relatively uniform regardless of the clinical severity, and consisted of Langerhans cells, eosinophils, histiocytes, plasma cells, giant cells and fibrosis. The treatment consisted of a combination of surgery, chemotherapy, and/or radiotherapy. Lymphadenopathy was the most common clinical presentation in our locality. Response to treatment was poor in patients with multisystem disease. Patients with age less than 2 years were more likely to have increased risk of morbidity and mortality, due to widespread disease.

Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a poorly understood proliferative disease, with different patterns of clinical presentation. Currently it is classified according to the number and type of system involved and the degree of organ dysfunction. The aetiology of the disease remains uncertain, and in some cases the disease is polyclonal, suggesting a reactive condition. Many cytokines have been implicated in the pathogenesis of LCH. Different therapeutic approaches can be considered depending on the affected organ, including surgery, radiotherapy and chemotherapy. Long-term organ dysfunction may remain, despite disease control and/or eradication, making indefinite supportive treatment mandatory. Here we present a literature review on all of the aspects of the disease, treatment approaches and existing protocols, and finally an adult clinical case.

Langerhans cell histiocytosis

The clinical manifestations of Langerhans cell histiocytosis have been recognized for more than a century. For most of that time, physicians have viewed the disease from different perspectives, interpreting portions of its clinical spectrum as if they were distinct and unrelated entities. More recently, Langerhans cell histiocytosis has been unified into a single concept, though the disease continues to defy traditional classification. By most accounts, Langerhans cell histiocytosis appears to be a morphologically benign proliferation of inflammatory cells that escapes regulatory control mechanisms. Studies from patients with all stages of the disease, however, document clonal proliferation of immune processing cells (i.e., Langerhans cells), suggesting a malignant disease process. The most common ophthalmic manifestation of Langerhans cell histiocytosis is a solitary lesion of orbital bone, which typically responds to minimally invasive therapy. The best management of solitary orbital Langerhans cell histiocytosis is debatable and has been complicated by its recent designation as a risk factor for central nervous system disease. This article summarizes recent developments in understanding the biology of Langerhans cell histiocytosis, reviews its ophthalmic manifestations, prognosis, and the controversy surrounding treatment of isolated orbital disease.

Langerhans cell histiocytosis: a review of the current recommendations of the Histiocyte Society

Langerhans cell histiocytosis is a rare proliferative disorder where pathologic Langerhans cells accumulate in a variety of organs. Historically, the nomenclature regarding this entity has been confusing because the disease had been subcategorized simply based upon the different clinical manifestations. In the following article, we summarize the current recommendation of the Histiocyte Society regarding the classification, evaluation, prognosis, and treatment of Langerhans cell histiocytosis.

Langerhans cell histiocytosis: update for the pediatrician

PURPOSE OF REVIEW

Langerhans cell histiocytosis is the commonest of the histiocytic disorders. Owing to the relative rarity of the condition, it remains a disease in which the diagnosis is often delayed or missed and in which many questions remain unanswered, ranging from etiology and pathogenesis to therapy. The management is often frustrating for care-givers and parents/patients. The purpose of the review is therefore to raise awareness of the disease and to highlight the clinical findings that should make the pediatrician or primary care-giver suspect the diagnosis, as well as current thinking regarding management of the various and diverse manifestations of this disease.

RECENT FINDINGS

We discuss new and interesting insights into the biology of Langerhans cell histiocytosis that raise the possibility of future targeted therapy. Important points in the diagnosis, investigation and management of the various forms of the disease are also discussed.

SUMMARY

We present a review of childhood Langerhans cell histiocytosis, highlighting new insights into pathogenesis and management of the various forms of this complex disease.

Systemic and endocrine manifestations of Langerhans' cell histiocytosis: current concepts in diagnosis and management

Langerhans' cell histiocytosis (LCH) is a rare disease of unknown etiology and variable biologic behavior and course. Almost every organ can be affected; however, it frequently involves the bones, lungs, skin and lymph nodes. LCH exhibits a particular predilection for involvement of the hypothalamo-pituitary axis resulting in diabetes insipidus and/or other anterior pituitary deficiencies. Although LCH can sometimes resolve spontaneously, it usually follows a chronic course and systemic treatment is mandatory for the management of multisystem disease. However, a significant number of patients will develop at least one permanent sequela as a consequence of the disease, with diabetes insipidus being the most common. A multidisciplinary approach is always needed in diagnosis, treatment and follow-up of all patients with LCH.

Pure cutaneous Langerhans cell histiocytosis resembling varicella

A 5-month-old boy presented with multiple, pinkish-yellow, umblicated, varicelliform vesicles on his trunk. The lesions first appeared on his scalp 2 months earlier. There was also an erythematous, moist and erosive eruption on both axillae, inguinal regions and intergluteal sulcus. He had been treated with topical antibacterial and antiviral therapies. Histopathological investigation of the lesions revealed the diagnosis of Langerhans cell histiocytosis. Systemic involvement was not detected, although detailed investigation was performed. We present our case because he had a varicelliform and intertriginous eruption but did not have internal organ and haematological involvement.

Langerhans cell histiocytosis of vulva in adolescent

Langerhans cell histiocytosis (LCH) affecting child vulva alone is a very rare disease. Only 13 cases of primary vulvar LCH have been previously reported in the medical literature. We describe an additional case in which the LCH was confined to the vulva, with review of the literature. A 16.5-year-old girl presented with papulous and ulcerative lesions on her labia majora and minora. The biopsy revealed a typical histopathologic finding consistent with LCH. A metastatic work-up did not reveal any evidence of the disease except on the vulva. Treatment was carried out according to LCH II protocol. The patient was diagnosed with a recurrent disorder in the vulva 8 months after the completion of primary chemotherapy. For this reason, she underwent second line treatment with 2-chlorodeoxyadenosine. Eighteen months after the second line chemotherapy, the patient has no signs of a local or systemic recurrence. Primary LCH of vulva is very unusual, but we have to keep in mind this possibility when an adolescent girl presents with an atypical chronic lesion on the vulva. This patient appears to be the first case of adolescent 16.5 year old having a solely cutaneous lesion of the vulva

Multiple Eyelid Defects in Cutaneous Langerhans Cell Histiocytosis

Langerhans cell histiocytosis is a disorder characterized by the proliferation of histiocytes of the mononuclear phagocyte system. Cutaneous Langerhans cell histiocytosis can develop as a solitary lesion or more frequently as part of a multisystem disease. This report describes a case of cutaneous Langerhans cell histiocytosis affecting the eyelids, resulting in a coloboma-like defect. The clinical features and management are discussed.

Adult Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a proliferative histiocytic disorder of unknown cause originating from dendritic cells. The clinical presentation of LCH is highly variable. Although the features of this disease have been well described in children, they remain poorly defined in adults. Here, we review the current knowledge about adult LCH, focussing on clinical presentation, diagnosis, treatment, and prognosis.