Langerhans cell histiocytosis: Current concepts and treatments. Cancer Treat Rev. 2010;36:354-359. [PMID: 20188480 DOI: 10.1016/j.ctrv.2010.02.012]

Langerhans cell histiocytosis: 23 years’ paediatric experience highlights severe long-term sequelae

Purpose

To review the presentation and outcome of patients with Langerhans cell histiocytosis attending The Royal Hospital for Sick Children, Glasgow over a 23-year period.

Method

Thirty-one children were diagnosed with Langerhans cell histiocytosis between January 1990 and December 2012. Retrospective information from medical records was gathered on age at diagnosis, presenting symptoms, classification of disease, treatment and long-term outcome.

Results

There were 17 boys and 14 girls; median age at diagnosis 2 years 9 months (interquartile range: 1 year 6 months to 4 years 4 months). Eleven were below 2 years and two were below 6 months of age at diagnosis. Eighteen (58%) children had single system disease of which four were multifocal; 13 (42%) had multisystem disease. Seventeen children improved with conservative treatment. Fourteen required steroids and dual agent chemotherapy; three required further chemotherapy. One child died. Two children had successfully treated relapses. Ten developed diabetes insipidus, seven were growth hormone deficient, two suffered from hypothyroidism and one panhypopituitarism. Median follow-up of the cohort was 8 years 10 months (interquartile range: 5 years 5 months to 12 years 7 months).

Conclusion

Langerhans cell histiocytosis is a rare disease in infants and young children, with a variable course ranging from self-limiting to life threatening. In very young children (under 2 years of age), multisystem disease is more common, requiring intensive chemotherapy and lifelong follow-up. Lasting sequelae were identified in over a third of patients, including endocrine dysfunction, hearing difficulties, neurological and psychological problems.

Langerhans cell histiocytosis in acute leukemias of ambiguous or myeloid lineage in adult patients: support for a possible clonal relationship

Four patients presented with acute leukemia of ambiguous or myeloid lineage in association with Langerhans cell histiocytosis and provide evidence suggesting a common origin of the two neoplasms. One patient had a non-constitutional trisomy 21 in both the leukemic blasts and the Langerhans cells indicative of a clonal relationship. A second case expressed CD2, CD13, and CD117 on both the Langerhans cells and the blasts suggesting a possible clonal relationship. All four cases exhibited geographic intermingling of the Langerhans cell histiocytosis and acute leukemia and shared unique features including extramedullary leukemia involving lymph nodes in all cases with Langerhans cell histiocytosis only present in sites involved by acute leukemia. T-cell antigen expression was present in all cases with one meeting criteria for mixed phenotype acute leukemia, T/myeloid, not otherwise specified. These findings support the concept that coexistent Langerhans cell histiocytosis and acute leukemia is clonally related in some cases. Furthermore, these cases of acute myeloid or acute leukemia of ambiguous lineage with Langerhans cell histiocytosis share some unique features suggesting a common underlying neoplastic hematopoietic stem cell.

Comparison of magnetic resonance imaging with invasive histological findings of Langerhans cell histiocytosis

Due to the rarity of skull Langerhans cell histiocytosis (LCH), correlations between abnormalities on magnetic resonance imaging (MRI) and pathological findings have not been fully evaluated. Only a few reports have as yet compared MRI of LCH infiltration and histological diagnostic features. A 22-year-old man with an unremarkable past medical history presented with headache followed by a nodular mass in the right parietal area. Gadolinium (Gd)-enhanced T1-weighted images showed a "mushroom-shaped" extension, extending from the subcutaneous to the intracranial space. The galeal tissue, the dura mater, and the cranium adjacent to the lesion showed enhancement on Gd-enhanced T1-weighted MRI. Histologically, diagnosis was LCH, with immunohistochemical positivity for S-100, CD68, and CD1a, and showed a MIB-1 labeling index of 29.5%. By immunostaining, we confirmed LCH cells to be present in the galea with Gd enhancement and the skull without Gd enhancement on MRI. LCH cells might exist in the marginal cranium, if MRI shows only slight intensity change without Gd enhancement. Further evaluation to determine pathologically proven extent of LCH and its relation with neuroradiological diagnosis as well as clinical outcome is needed to understand heterogeneous response to surgical and/or nonsurgical treatment in LCH.

Clinical features and treatment outcomes of Langerhans cell histiocytosis: a nationwide survey from Korea histiocytosis working party

A nationwide survey was conducted to clarify the clinical features and outcomes of Korean children with Langerhans cell histiocytosis (LCH). Korea Histiocytosis Working Party analyzed the data of 603 patients who were diagnosed with LCH between 1986 and 2010 from 28 institutions in Korea. Median age at diagnosis was 65 months (range, 0 to 276 mo). Bone was the most frequently affected organ (79.6%) followed by skin (19.2%). Initially, 419 patients (69.5%) had single-system involvement (SS), 85 (14.1%) with multisystem (MS) disease without risk organ involvement (MS-RO), and 99 (16.4%) multisystem disease with risk organ involvement (MS-RO). The 5-year overall survival (OS) rates in the SS, MS-RO, and MS-RO groups were 99.8%, 98.4%, and 77.0%, respectively (P<0.001), and the 5-year reactivation rates were 17.9%, 33.5%, and 34.3%, respectively (P<0.001). The OS rate was lower in patients with RO involvement (P=0.025) and lack of response to initial treatment (P=0.001). MS involvement (P=0.036) was an independent risk factor for reactivation. Permanent consequences were documented in 99 patients (16.4%). Reactivation of disease, MS involvement, and age at diagnosis ≤ 2 years were associated with higher incidence of permanent consequences. This study emphasized that further efforts are required to improve survival of MS-RO patients and reduce reactivation in younger patients with MS involvement.

BRAF--a new player in hematological neoplasms

BRAF oncogenic kinase has become a target for specific therapy in oncology. Genetic characterization of a predominant V600E mutation in melanoma, thyroid cancer, and other tumors became a focus for developing specific inhibitors, such as vemurafenib or dabrafenib. Our knowledge regarding the role of mutated BRAF in hematological malignancies has grown quickly as a result of new genetic techniques such as next-generation sequencing. This review summarizes current knowledge regarding the role of BRAF in lymphoid and myeloid neoplasms, with a focus on hairy-cell leukemia, Langerhans cell histiocytosis, and Erdheim-Chester disease.

Blood dendritic cells: "canary in the coal mine" to predict chronic inflammatory disease?

The majority of risk factors for chronic inflammatory diseases are unknown. This makes personalized medicine for assessment, prognosis, and choice of therapy very difficult. It is becoming increasingly clear, however, that low-grade subclinical infections may be an underlying cause of many chronic inflammatory diseases and thus may contribute to secondary outcomes (e.g., cancer). Many diseases are now categorized as inflammatory-mediated diseases that stem from a dysregulation in host immunity. There is a growing need to study the links between low-grade infections, the immune responses they elicit, and how this impacts overall health. One such link explored in detail here is the extreme sensitivity of myeloid dendritic cells (mDCs) in peripheral blood to chronic low-grade infections and the role that these mDCs play in arbitrating the resulting immune responses. We find that emerging evidence supports a role for pathogen-induced mDCs in chronic inflammation leading to increased risk of secondary clinical disease. The mDCs that are elevated in the blood as a result of low-grade bacteremia often do not trigger a productive immune response, but can disseminate the pathogen throughout the host. This aberrant trafficking of mDCs can accelerate systemic inflammatory disease progression. Conversely, restoration of dendritic cell homeostasis may aid in pathogen elimination and minimize dissemination. Thus it would seem prudent when assessing chronic inflammatory disease risk to consider blood mDC numbers, and the microbial content (microbiome) and activation state of these mDCs. These may provide important clues (“the canary in the coal mine”) of high inflammatory disease risk. This will facilitate development of novel immunotherapies to eliminate such smoldering infections in atherosclerosis, cancer, rheumatoid arthritis, and pre-eclampsia.

Soft tissue Langerhans cell histiocytosis with secondary bone involvement in extremities: evolution of lesions in two patients

Langerhans cell histiocytosis (LCH) is an uncommon disorder of unknown etiology with a wide spectrum of biological behavior. The most common sites of involvement are bone, skin, and lung. While osseous LCH can result in secondary soft tissue involvement, primary soft tissue LCH in extremities with secondary bone involvement is rare, and little is known about its natural course. We report two adult patients with multi-organ system LCH who had primary soft tissue lesions with secondary involvement of adjoining bones in lower extremities, and illustrate the important role played by various imaging modalities in detection and monitoring of treatment response. We also document spontaneous clinical resolution of LCH lesions without therapy, and positive response of these lesions to chemotherapy.

Management of adult Langerhans cell histiocytosis based on the characteristic clinical features

To find out the most appropriate management, clinical features of 18 cases of adult multisystem langerhans cell histiocytosis (LCH) have been analyzed. The patients comprising of 9 males and 9 females were median age of 36 years, ranging from 18-53 years at diagnosis. Regarding the initial symptoms, 7 patients (2 males and 5 females) showed central diabetes insipidus (CDI) and other endocrine symptoms with thickened pituitary stalk or a mass at the hypothalamic region. Additional 2 patients initiated the disease with CDI with no immediate diagnosis. In the remaining patients, the disease begun with single (n = 3) or multiple (n = 1) spinal bone lesion(s) in 4 patients (all males), with multiple bone lesions in 3 patients (1 male and 2 females), with single skull lesion in one female patient and with ambiguous symptoms including hypothyroidism in the remaining one male patient. We also recognized the correlation between pregnancy/childbirth and LCH in 4 patients. In terms of treatment, 9 patients received systemic immuno-chemotherapy alone, of which the majority received vinblastine-based chemotherapy while 4 received 2-chlorodeoxyadenosine. Five had a combination of immuno-chemotherapy with surgical resection or radiotherapy, 2 had immunotherapy alone, 2 had surgical resection followed by observation alone to date. Three patients received hematopoietic stem cell transplantation after extensive chemotherapy. In terms of outcome, 15 patients are alive (9 with active disease, 6 without active disease), with a median of 66 mo (range 17-166 mo), two died of disease while the remaining 1 lost to follow-up. Based on these results, we think that early diagnosis and rapid introduction of appropriate treatment are essential, in order to overcome the problems relevant to adult LCH.

Cancer risk in children and adolescents with birth defects: a population-based cohort study

Objective

Birth defects are an increasing health priority worldwide, and the subject of a major 2010 World Health Assembly Resolution. Excess cancer risk may be an added burden in this vulnerable group of children, but studies to date have provided inconsistent findings. This study assessed the risk for cancer in children and young adolescents with major birth defects.

Methods and Findings

This retrospective, statewide, population-based, cohort study was conducted in three US states (Utah, Arizona, Iowa). A cohort of 44,151 children and young adolescents (0 through 14 years of age) with selected major, non-chromosomal birth defects or chromosomal anomalies was compared to a reference cohort of 147,940 children without birth defects randomly sampled from each state’s births and frequency matched by year of birth. The primary outcome was rate of cancer prior to age 15 years, by type of cancer and type of birth defect. The incidence of cancer was increased 2.9-fold (95% CI, 2.3 to 3.7) in children with birth defects (123 cases of cancer) compared to the reference cohort; the incidence rates were 33.8 and 11.7 per 100,000 person-years, respectively. However, the excess risk varied markedly by type of birth defect. Increased risks were seen in children with microcephaly, cleft palate, and selected eye, cardiac, and renal defects. Cancer risk was not increased with many common birth defects, including hypospadias, cleft lip with or without cleft palate, or hydrocephalus.

Conclusion

Children with some structural, non-chromosomal birth defects, but not others, have a moderately increased risk for childhood cancer. Information on such selective risk can promote more effective clinical evaluation, counseling, and research.

A Rare Disease in Adult: Langerhans Cell Histiocytosis

Langerhans cell histiocytosis is a rare histiocytic disorder and has been diagnosed in all age groups, but is most common in children. This disease is very rare in adults. We presented a patient who was 62 years old man diagnosed langerhans cell histiocytosis.

Multisystem Langerhans cell histiocytosis presenting as an oral lesion

Langerhans cell histiocytosis (LCH) is a rare proliferative disorder in which the pathologic Langerhans cells infiltrate and destroy the tissues. Patients with LCH present varied clinical manifestations. Cutaneous lesions in LCH manifest as vesiculopapular eruptions that often mimic various infectious diseases particularly in infants. We present a case of a female infant with an ulcerative lesion intraorally. The baby was asymptomatic otherwise. A detailed history revealed the presence of cutaneous lesions that was overlooked by her parents.

CONCLUSION

This report tries to briefly discuss the current concepts regarding the etiology of LCH. An attempt has been made to emphasis the need for a through systemic examination. The protocol of investigative procedures to be adopted in LCH is also discussed.

Langerhans cell histiocytosis in non-twin siblings

Langerhans cell histiocytosis (LCH), which has unknown pathogenesis, can manifest as many kinds of signs and symptoms at any age. Although its genetic background has not been exactly identified, the familial clustering of this disease has been described in some reports. It is very uncommon, however, in siblings who are not monozygotic or dizygotic twins. Reported herein is a case of LCH in non-twin siblings (younger sister and elder brother) who were diagnosed at 3.3 and 14.5 years of age, respectively, and successfully treated with chemotherapy, with BRAF V600E mutation status, and a brief review of the literature.

Langerhans cell histiocytosis of the orbit

PURPOSE

The management of Langerhans cell histiocytosis is controversial. This study evaluated our clinical experience and therapeutic results in orbital Langerhans cell histiocytosis.

METHODS

This is a retrospective, noncomparative interventional case series involving 17 consecutive patients with biopsy-proven orbital Langerhans cell histiocytosis. Response to surgery and chemotherapy and development of diabetes insipidus were the main outcome measures.

RESULTS

Thirteen (76.5%) of the patients were male and the mean age at diagnosis was 10.7 years (range 2-39 years). The most frequent presenting sign was proptosis (8 patients) and upper eyelid edema (4 patients). Pain was present in 5 cases and periocular redness in 6. No patient reported a history of trauma. The frontal bone was involved in 16 patients followed by the zygomatic in 9 cases. Five patients also had lesions in the calvarium, femur, facial, temporal, and parietal bones. No patients had systemic disease. Ten patients were managed with vinblastine (0.2 mg/kg, 6-12 months) chemotherapy because of major residual tumor burden (5 cases) and multi-bone involvement (5 cases). Four patients were observed following macroscopically complete tumor removal. Three patients with limited anterior orbital soft tissue tumors and single bone involvement received systemic corticosteroids (40 mg/m2/d, 6-10 weeks). No patients developed diabetes insipidus after a median follow-up of 46 months.

CONCLUSIONS

Macroscopically complete excision of the unifocal tumors may not necessitate any further treatment. Vinblastine chemotherapy following incomplete tumor removal and in patients with multifocal bone disease resulted in recurrence-free survival at 3 years in 90% of patients.

Langerhans cell histiocytosis of the orbit: five clinicopathologic cases and review of the literature

Langerhans cell histiocytosis (LCH) is a proliferation of Langerhans cells intermixed with inflammatory cells, in particular eosinophils, that may manifest as unisystem (unifocal or multifocal) or multisystem disease. Orbital involvement typically manifests as a solitary lesion that carries a favorable prognosis. We describe the clinical and histologic spectrum of LCH of the orbit in our five cases. One patient exhibited multifocal unisystem disease; the other four had a localized process. Typical histologic features included numerous histiocytes with varying degrees of giant cell formation and scattered eosinophilic granulocytes. The presence of Langerhans cells was confirmed by CD1a and S100 immunohistochemistry. Transmission electron microscopy demonstrated characteristic intracytoplasmic Birbeck granules. We review the different ophthalmic manifestations of LCH and treatment strategies. As LCH may solely involve the orbit, treatment is based on the degree of organ involvement. LCH should included in the differential diagnosis in tumors of the ocular adnexae, especially in young children.

Infantile juvenile xanthogranuloma of the chest wall mimicking mesenchymal hamartoma: report of a case

Juvenile xanthogranuloma (JXG) is essentially a benign neoplasm arising from any site on the body; however, there has so far been only one report of JXG located on the chest wall involving a rib. This report presents a rare case finally diagnosed as JXG based on histopathological and immunohistochemical examinations.

Use of the JL1 epitope, which encompasses the nonglycosylation site of CD43, as a marker of immature/neoplastic Langerhans cells

Langerhans cell histiocytosis (LCH) is the collective designation for a group of proliferative disorders of antigen-presenting cells in the epidermis. Over the past several decades, the etiology of LCH has been a controversial issue, particularly with respect to the pathologic process, that is, whether it is a neoplastic or inflammatory process. Recently, it was reported that the JL1 epitope, which encompasses the nonglycosylation site of CD43, is only exposed in the precursor stages of hematopoietic cells or in neoplastic conditions. We sought to investigate the possible utility of the JL1 monoclonal antibody as a diagnostic marker of LCH. In this study, we compared the staining characteristics of antibodies against the JL1 epitope with those of langerin and CD1a, which are widely used for the diagnosis of LCH. We found substantial differences in the staining patterns of these markers. The JL1 epitope could be bound by antibodies in cases of LCH and Langerhans cell (LC) sarcoma. In non-neoplastic lesions, JL1-positive LCs were found only in dermatitis, reflecting the immaturity of LCs in inflamed skin. However, anti-langerin antibodies were able to identify any form of LC, including those in normal skin, dermatitis, dermatopathic lymphadenopathy, and LCH. On the basis of these findings, we propose that the anti-JL1 antibody is a specific marker of immaturity, a feature that is shared in neoplastic LCs, and can be useful in the diagnosis of LCH.

Langerhans cell histiocytosis of the cranial base: is low-dose radiotherapy effective?

Introduction. Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology with different clinical features. A standardised treatment has not been established so far. Case Report. We report a case of a 28-year-old patient who initially presented with hypesthesia of the fifth cranial nerve and pain of the left ear. Diagnosis showed a tumour localised in the cranial base with a maximum diameter of 4.1 cm. The diagnosis of LCH was confirmed histologically by biopsy. Diagnostic workup verified the cranial lesion as the sole manifestation of LCH. A total dose of 9 Gy (single dose 1.8 Gy) was delivered. The symptoms dissolved completely within 6 months after radiation; repeated CT and MRI scans revealed a reduction in size of the lesion and a remineralisation of the bone. After a followup of 13 years the patient remains free of symptoms without relapse or any side effects from therapy. Discussion. Due to the indolent course of the disease with a high rate of spontaneous remissions the choice of treatment strongly depends on the individual clinical situation. In the presented case low-dose radiotherapy was sufficient to obtain long-term local control in a region with critical structures and tissues.

The usefulness of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in patients with Langerhans cell histiocytosis

OBJECTIVE

Langerhans cell histiocytosis (LCH) has a wide spectrum of clinical manifestations, ranging from spontaneous resolution to rapid progression or death, with the risk of permanent consequences. F-18 FDG PET/CT has been used for assessment of LCH patients. However, its clinical implication has not been well elucidated, mainly due to very low incidence of LCH. The aim of this study was to evaluate the clinical usefulness of F-18 FDG PET/CT in LCH patients.

METHODS

A database of 12 patients (mean age 17.8 ± 17.9 years; 7 children, 5 adults) who were diagnosed histopathologically as LCH was retrospectively reviewed. Two patients underwent F-18 FDG PET/CT before and after therapy, 6 patients underwent only before therapy and 4 patients underwent only after therapy.

RESULTS

Nine (75.0%) and 3 patients (25.0%) had single-system (single site and multiple sites) and multisystem involvements, respectively. Pretreatment SUV(max) of patients with multisystem or multiple site involvement of a single-system was significantly higher than that of patients with single site involvement of a single-system (3.29 ± 2.52 vs. 1.63 ± 0.52, p = 0.025). One patient showed multisystem risk organs (lung and bone marrow) involvement. In 2 patients, F-18 FDG PET/CT detected additional active LCH lesions not identified on conventional imaging modalities. In follow-up F-18 FDG PET/CT scans, complete resolution was identified in 2 patients and reactivation in another 2 patients.

CONCLUSIONS

Results of this study suggest that F-18 FDG PET/CT is useful for identification of active lesions, stratification of disease stages, monitoring of therapeutic response, and detection of reactivation in LCH patients.

Immunohistochemical and molecular cytogenetic evaluation of potential targets for tyrosine kinase inhibitors in Langerhans cell histiocytosis

Langerhans cell histiocytosis is a rare disorder of Langerhans cells, a component of the dendritic cell system, with an unknown pathogenesis. Conventional therapy for patients with Langerhans cell histiocytosis is usually effective, but some patients are refractory to treatment or develop toxicity. Thus, there is a need for innovative therapies. Recently, some cases of Langerhans cell histiocytosis were reported to express platelet-derived growth factor receptors α and β or c-KIT by immunohistochemistry, and some of these patients had a clinical response to imatinib mesylate. Other hematologic disorders with PDGFRα or PDGFRβ gene rearrangements also have responded to imatinib mesylate. The aim of this study was to evaluate immunohistochemical and molecular markers in Langerhans cell histiocytosis that would identify cases for possible treatment with tyrosine kinase inhibitors. We investigated formalin-fixed, paraffin-embedded tissue sections from 14 cases of Langerhans cell histiocytosis. As controls, we included cases of inflammatory dermatitis (n = 5) and dermatopathic lymphadenitis (n = 7). We performed immunohistochemistry for S100, CD1a, c-KIT, and platelet-derived growth factor receptors α and β. Fluorescence in situ hybridization analysis to detect rearrangements of the PDGFRα or PDGFRβ genes was also performed. Four (28.5%) of 14 cases of Langerhans cell histiocytosis were positive for platelet-derived growth factor receptor α, whereas absent/weak expression was seen in 10 cases and all controls. All cases were negative for platelet-derived growth factor receptor β and c-KIT. The fluorescence in situ hybridization studies were also negative in all 8 cases with adequate quality DNA. Our findings suggest that a subset of cases of Langerhans cell histiocytosis may be treated with tyrosine kinase inhibitors due to the expression of platelet-derived growth factor receptor α. Clinical trials that evaluate the use of tyrosine kinase inhibitors in Langerhans cell histiocytosis seem warranted and should evaluate these markers.

Langerhans's cell histiocytosis in old subjects: two rare case reports and review of the literature

BACKGROUND

Langerhans cell histiocytosis (LCH) is a proliferative disease of histiocyte-like cells that generally affects children; LCH onset is rare in adults; immunohistochemistry is essential to obtain the correct diagnosis, and treatment protocols are controversial.

OBJECTIVE

To describe two new cases of adult onset oral LCH.

CASE REPORTS

Case 1: a 71-year-old woman, complaining of diffuse oral pain, presented with erythematous mucosal lesions; the panoramic radiograph and CT scan showed multiple mandible radiolucent areas. Immunohistochemical assay for S-100, CD1a and langerin test was essential in reaching the correct diagnosis. Case 2: a 77-year-old female patient presented with a non-painful, non-bleeding, slightly elevated erythematous palatal lesion of 6 months duration, together with a genital vulvar lesion of uncertain nature. The pathology confirmed the diagnosis of LCH. Many therapies (etoposid, radiotherapy) could induce only a clinical partial remission; Cladribine induced a complete recovery.

CONCLUSION

The first case was difficult to diagnose: the clinical presentation and course of the disease (LCH) in the elderly are multiple and unpredictable. An immunohistochemistry study is often essential to obtain the correct diagnosis. The second case required several therapeutic interventions: even though some cases regress spontaneously, others require systemic chemotherapy.

Splenomegaly unresponsive to standard and salvage chemotherapy in Langerhans cell histiocytosis: a case of extramedullary hematopoiesis

Langerhans cell histiocytosis (LCH) is a proliferative disorder of dendritic cells which has evaded efforts to clearly define pathogenesis, diagnostic criteria, and therapeutic response markers. Strides have been made at classification with the recent development of a quantified score of disease severity. Splenic involvement is an indicator of poor prognosis, with spleen size its surrogate marker in evaluation and scoring. We describe a case of pediatric LCH with progressive splenomegaly despite treatment, which when examined at splenectomy revealed no LCH involvement but extramedullary hematopoiesis. These findings thus challenge our understanding of splenomegaly as a marker of disease.

Does adjunctive chemotherapy reduce remission rates compared to cortisone alone in unifocal or multifocal histiocytosis of bone?

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare disorder that can affect almost any organ, including bone. Treatment options include local corticosteroid infiltration in isolated bone lesions and oral corticosteroids and chemotherapy in multifocal bone lesions. Several studies show local corticosteroid injection in unifocal bone lesions heal in more than 75% of patients with minimal side effects. Therefore, it is unclear whether chemotherapy adds materially to the healing rate.

QUESTIONS/PURPOSES

We therefore compared overall survival, remission rate, and recurrence rate in patients with bone LCH treated with chemotherapy and corticosteroids or corticosteroids alone.

METHODS

We retrospectively reviewed the records of 198 patients with LCH since 1950. Median age at diagnosis was 5 years, male-to-female ratio was 1.33, and the most frequent symptom was local pain (95%). We recorded the disease presentation, demographics, treatment, and clinical evolution of each patient. Minimum followup was 4 months (median, 24 months; range, 4-360 months).

RESULTS

The survival rate of the systemic disease group was 76.5% (65 of 85) while the survival rate in the unifocal and multifocal bone involvement groups was 100% at a median 5-year followup. All patients with unifocal bone involvement and 40 of 43 (93%) with multifocal bone involvement had complete remission. One of 30 patients with multifocal bone involvement treated with chemotherapy and oral corticosteroids did not achieve remission whereas two of six receiving only corticosteroids did not achieve remission.

CONCLUSIONS

Our observations suggest intralesional corticosteroid injection without adjunctive chemotherapy achieves remission in unifocal bone LCH but may not do so in multifocal single-system bone involvement. Larger series would be required to confirm this observation.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

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 - a case report

A 17-year-old male presented for dermatologic consultation with slightly elevated reddish papules covered by yellowish scales in the scalp for the last two years and reddish and indurated ulcers in the perineum lasting six months. Additional complaints included polyuria, polydipsia, delay in the development of secondary sexual characteristics and hearing loss of the right ear secondary to a medium otitis. Lesions from scalp and perineum were sampled for histopathologic examination and revealed a dense cellular infiltrate made up of mononuclear cells with conspicuous eosinophilic cytoplasm and large cleaved vesicular nucleus, some of them with shapes resembling the format of a kidney and others reminiscent of coffee beans. Numerous intermingling eosinophils were present. The diagnosis of Langerhans cell histiocytosis was then rendered and confirmed by positive immunostaining of neo-plastic cells for anti-CD1a and anti-S100 protein antibodies. The work-up revealed diabetes insipidus, hypogonadotropic hypogonadism, hiperprolactenemia, growing-hormone deficiency and thickness of the pituitary stalk. The patient was treated with prednisone and vinblastin based chemotherapy regimen for six months with complete remission, but presented recurrence of some lesions in the scalp, which were handled with topical mustard and corticosteroids. After chemotherapy, the endocrinologic disturbances were corrected with hormonal replacement therapy. The patient is currently in good health with a follow-up of five years.

A rare cause of goiter: Langerhans cell histiocytosis of the thyroid

Goiter is a very common clinical problem; however, Langerhans cell histiocytosis (LCH) with thyroid involvement that presents as a goiter is very rare. In this article, we report one case of thyroid LCH. An 18-year-old male patient presented with goiter, polyuria, polydipsia, and lymphadenectasis of the neck, and LCH was confirmed by a lymph node biopsy and pathological investigation. Without a thyroidectomy, the goiter shrank after nine cycles of chemotherapy. In addition, we summarize the reported thyroid LCH cases in the literature from the last 10 years. LCH usually involves other organs, such as the lungs, bones, skin, pituitary gland, and lymph nodes. Thyroid LCH is more common in adults than in children, and it may coexist with a thyroid carcinoma. Without any unique thyroid manifestations, either clinically or by imaging, it is difficult to distinguish thyroid LCH from other thyroid diseases. Pathology is the gold standard for the diagnosis of LCH. A fine needle aspiration biopsy (FNAB) may help to diagnosis LCH, although sometimes it leads to misdiagnosis. Chemotherapy is recommended for multi-system LCH. Younger patients with widespread disease or who are non-responsive to chemotherapy have poor outcomes.

Radiologic findings of adult pelvis and appendicular skeletal Langerhans cell histiocytosis in nine patients

OBJECTIVE

The purpose of this article was to evaluate the radiologic findings of adult pelvis and appendicular skeletal Langerhans cell histiocytosis (LCH), emphasizing the CT and MR findings.

MATERIALS AND METHODS

The images of nine patients with pathologically proven LCH (five men and four women; mean age, 37.11 years) were retrospectively reviewed. Imaging analysis was confined to the long and flat bones. CT scans were performed in five patients and MR imaging was performed in eight. Images were assessed for the following features on CT and MRI: the location and number of lesions; the presence of cortical destruction, endosteal scalloping, and a periosteal reaction on CT or MRI; the margin of soft tissue masses, the presence of bone marrow edema, and a "budding" appearance on MRI; and the presence of sclerotic margins or septations on CT.

RESULTS

The involved skeletal sites were the pelvis (seven), femurs (five), humeri (two), tibias (two), fibula (one), clavicle (one), scapula (one), and sternum (one). Endosteal scalloping, a periosteal reaction, and a budding appearance were common on MRI or CT images. Although cortical destruction and the soft tissue lesion formation were rare, soft tissue masses had well-defined margins.

CONCLUSIONS

Endosteal scalloping and a budding appearance with a periosteal reaction on CT and MRI may be helpful signs for differentiation of LCH from malignant tumors in adults.

Multisystem Langerhans cell histiocytosis with liver dysfunction as the first presentation: A case report

Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology characterized by oligoclonal proliferation of Langerhans cells. The diagnosis of LCH is complicated by the fact that it may involve multiple organ systems and its clinical presentation and course varies, ranging from an isolated to a multisystem disease. We report a 35-year-old male with LCH involving multiple systems, including the bones, lungs, spleen, liver and bile ducts, whose first clinical presentation was liver dysfunction. The patient was diagnosed following a skull biopsy that revealed infiltration of Langerhans cells. However, a liver biopsy revealed sclerosing cholangitis (SC) with no signs of Langerhans cell infiltration, and the clinical manifestations of the involved organs were atypical, leading to a delayed diagnosis. The patient was in partial remission following chemotherapy. In conclusion, findings of this case may aid our understanding of the pathophysiology of LCH and in improving its diagnosis and treatment.

Treatment of patients with hypothalamic-pituitary lesions as adult-onset Langerhans cell histiocytosis

We report four cases of adult-onset Langerhans cell histiocytosis (LCH) with central nervous system (CNS) lesions in the hypothalamic-pituitary region. The first clinical symptoms were diabetes insipidus (two patients), hypothyroidism (one patient), and decreased libido/erectile dysfunction (one patient). Diagnosis was delayed as the CNS lesion was not initially suspected to be secondary to LCH, with a median time from symptom onset to treatment of 3.0 (range <1-5.3) years. In three patients, the tumor mass was effectively reduced by chemotherapy; however, all patients continue to exhibit hypopituitarism. Early diagnosis and initiation of treatment are required to improve the outcome of CNS-LCH in adult patients.

Multisystem Langerhans cell histiocytosis in children: current treatment and future directions

Langerhans cell histiocytosis (LCH) is a rare (about 3-5 cases per million children aged 0-14 years), non-malignant disease characterized by proliferation and accumulation of clonal dendritic cells, extreme clinical heterogeneity, and an unpredictable course. Three large-scale, international, prospective therapeutic studies (LCH-I to III) for multisystem LCH (MS-LCH) have been conducted by the Histiocyte Society since 1991. The cumulative lessons from these studies are summarized in this review. Patients with MS-LCH represent a heterogeneous group with respect to disease severity and outcome, therefore treatment stratification and risk-tailored treatment are mandatory. The risk for mortality can be predicted based on involvement of 'risk organs' (e.g. hematopoietic system, liver, and/or spleen) at diagnosis and on response to initial therapy (assessed after 6-12 weeks of treatment). Thus, patients without involvement of risk organs (low-risk group) are not at risk for mortality but need systemic therapy in order to control the disease activity and avoid reactivations and permanent consequences. Patients with risk organ involvement (risk group) are at risk for mortality, and lack of therapy response defines a subgroup with a particularly dismal prognosis (high-risk group). Those patients in the risk group who respond to therapy and survive are at risk for reactivations and permanent consequences. The LCH-I study compared the efficacy of vinblastine and etoposide, and concluded that they are equivalent single-agent treatments for children with MS-LCH. However, the results of this trial were inferior with respect to response rate at week 6, disease reactivation rate, and sequelae, when compared with historical trials using more intensive regimens. The combination of prednisolone and vinblastine was established as a standard first-line treatment through the LCH-II and LCH-III studies. The regimen consists of one to two 6-week courses (continuous oral corticosteroids 40 mg/m2/day for 4 weeks, tapered over 2 weeks plus weekly vinblastine intravenous push) of initial therapy, followed by a continuation phase (three weekly pulses of oral prednisolone 40 mg/m2/day for 5 days plus a vinblastine injection). The addition of a third drug to the standard combination (etoposide in LCH-II and methotrexate in LCH-III) failed to significantly improve survival in the risk group. The remaining mortality in the risk group is about 20%, and up to 40% in the high-risk group. Concerning low-risk MS-LCH, comparison of results of the LCH-II study with historical data suggested that the remaining reactivation rate of about 50% (and possibly permanent consequences) could be reduced by prolongation of the total treatment duration. To study this hypothesis, in the low-risk group of the LCH-III study standard maintenance therapy was randomly given for a total treatment duration of 6 and 12 months. Unpublished preliminary data from this recently closed trial suggested that prolongation of the treatment duration may significantly improve reactivation-free survival. In summary, several studies have shown that systemic therapy is indicated for all patients with MS-LCH. A standard two-drug regimen consisting of an initial 'intensive' phase for 6-12 weeks, followed by a less intensive 'maintenance phase' for a total treatment duration of at least 12 months is recommended for patients treated outside of clinical trials. Non-responders, particularly those with progressive disease in risk organs, are eligible for experimental salvage approaches. Remaining questions will be addressed in the upcoming LCH-IV trial, which is in the process of intensive preparation.