Late Diagnosis of Langerhans Cell Histiocytosis by Skin Biopsy in a Lung Transplant Candidate Patient

We present the case of a lung transplant candidate under veno-venous membrane oxygenation assistance (VV ECMO) whose diagnosis of emphysema of undetermined etiology was redefined as Langerhans cell histiocytosis (LCH) due to a scalp skin biopsy performed years after the beginning of his respiratory symptoms. A 20-year-old patient started three years before his admission with progressive dyspnea leading to a diagnosis of bullous emphysema of undetermined cause, which evolved into respiratory failure and evaluation for bilateral lung transplant. Three years later, he developed bilateral pneumonia requiring mechanical ventilation. When refractory hypoxemia ensued, he had to be placed on VV ECMO. Under these conditions, he was transferred to our center and listed for a bilateral pulmonary transplantation. Forty-eight hours after admission, and due to intense polyuria, central diabetes insipidus was diagnosed. In this clinical context, the presence of cutaneous lesions on the scalp was reconsidered and biopsied under the presumption of possible LCH, with pathology analysis confirming the diagnosis. He continued to be assisted with VV ECMO for 66 more days as a bridge to transplantation, developing multi-organ failure and passing away before a donor organ was available. The diagnosis of LCH should be considered in any adult patient with bullous emphysema of undetermined cause. Given the possibility of early therapeutic interventions, the search for its clinical associations (e.g., diabetes insipidus and/or skin lesions) should be a systematic part of the etiologic workup. The availability of skin specimens to reach a diagnosis makes its thorough search an important part of the diagnostic approach.

Langerhans cell histiocytosis: current advances in molecular pathogenesis

Langerhans cell histiocytosis (LCH) is a rare and clinically heterogeneous hematological disease characterized by the accumulation of mononuclear phagocytes in various tissues and organs. LCH is often characterized by activating mutations of the mitogen-activated protein kinase (MAPK) pathway with BRAFV600E being the most recurrent mutation. Although this discovery has greatly helped in understanding the disease and in developing better investigational tools, the process of malignant transformation and the cell of origin are still not fully understood. In this review, we focus on the newest updates regarding the molecular pathogenesis of LCH and novel suggested pathways with treatment potential.

A rare imaging presentation with multisystemic clinicopathological features of Langerhans cell histiocytosis: Case report and literature review

RATIONALE

Langerhans cell histiocytosis (LCH) is a kind of rare disease in which dendritic cells proliferate abnormally. It often occurs in children and can involve any tissue and organ. The affected sites usually include bone, skin, pituitary gland, and lungs, while the thyroid gland and external auditory canal are rarely observed. The perineal and labial involvement of this disease has not been reported yet.

PATIENT CONCERNS

A 47-year-old female patient experienced a swelling of the anterior neck area without an obvious inducement. She noticed a quail egg-like mass on the left side, and the mass increased progressively within 3 months. The anterior neck area was found to be swollen, and some flaky red rashes were seen on the scalp and bilateral external auditory canals.

DIAGNOSES

Imaging examination showed enlarged thyroid and cervical lymph nodes, multiple low-density nodules in the liver, and reduced signal in the posterior pituitary gland. The biopsy pathological result of the increased left cervical lymph node indicated that LCH was detected.

INTERVENTIONS

VP regimen (vincristine, dexamethasone per os) and related supportive treatments were given as inducing chemotherapy for 6 weeks.

OUTCOMES

After the second chemotherapy, the rash on the scalp and external auditory canal improved, and the neck mass was significantly reduced. After the third chemotherapy, the rash was mostly disappeared, while the neck lumps increased during chemotherapy. Thus, clatribine chemotherapy was recommended as the follow-up.

LESSONS

Imaging examinations played an important role in the diagnosis and follow-up of the disease, especially 18F-FDG PET/CT, which could show multiple involving organs at the same time. When a patient suffering from diabetes insipidus, skin rash, or fever, has a high FDG uptake PET/CT result in multiple tissues and organs throughout the body, it is necessary to consider the possibility of LCH.

Pediatric diencephalic tumors: a constellation of entities and management modalities

The diencephalon is a complex midline structure consisting of the hypothalamus, neurohypophysis, subthalamus, thalamus, epithalamus, and pineal body. Tumors arising from each of these diencephalic components differ significantly in terms of biology and prognosis. The aim of this comprehensive review is to describe the epidemiology, clinical symptoms, imaging, histology, and molecular markers in the context of the 2021 WHO classification of central nervous system neoplasms. We will also discuss the current management of each of these tumors.

Orbital Langerhans Cell Histiocytosis: A Case Report

An eight-year-old boy presented with a one-month history of left eyelid swelling. The patient was diagnosed with periorbital cellulitis at another clinic and was treated with oral antibiotics. However, the swelling did not subside. On initial consultation, the patient had left upper eyelid swelling with erythema. His extraocular muscle motility was normal, and the results of blood tests were unremarkable. A computed tomographic scan demonstrated a mass in the superior orbit with destructive changes in the left frontal bone. Histopathological examinations revealed a dense infiltrate of histiocytic cells. Immunohistochemical staining of the tumors for CD1a and Langerin was positive. A pathological diagnosis of Langerhans cell histiocytosis was made. Since orbital Langerhans cell histiocytosis has a high risk for central nervous system involvement, chemotherapy was the treatment of choice for any residual lesion to prevent sequelae to the central nervous system. At the six-month follow-up, the lesion did not recur, and the patient did not experience any central nervous system sequela.

A Case of a Coexisting Carcinosarcoma Ex Pleomorphic Adenoma With Langerhans Cell Histiocytosis in the Parotid Gland

Carcinosarcoma ex pleomorphic adenoma is a rare malignant neoplasm, with most cases reported in the parotid gland. We herein report a case of a 75-year-old male referred to our hospital with a long-standing right parotid lesion that was treated in an outside hospital by a superficial parotidectomy. The patient reported a painful, rapidly enlarging mass following the excision. Histopathological examination showed the proliferation of malignant epithelial and mesenchymal elements with a solid sheet of Langerhans cells admixed with eosinophils. The Langerhans cells were reactive to CD1a and BRAF; hence, a diagnosis of carcinosarcoma ex pleomorphic adenoma with Langerhans cell histiocytosis was given. Complete clinical and radiographic workup showed no other organ involvement. The patient underwent total parotidectomy with adjuvant chemoradiation; however, the tumor progressed and showed lung metastasis. We herein report the first case of a concurrent Langerhans cell histiocytosis with associated carcinosarcoma ex pleomorphic adenoma.

Acute Bacterial Meningitis and Petrous Apicitis in a Child with Aplasia Cutis Congenita: A Case Report

Petrous apicitis and acute bacterial meningitis are uncommon in the present antibiotic era. The diagnosis of petrous apicitis is seldom considered unless there is cranial nerve palsy. A young child with aplasia cutis congenita presented with acute bacterial meningitis and an incidental opacified left mastoid in brain imaging. During the course, fever persisted, and high-resolution temporal bone imaging showed rapid progression to coalescent mastoiditis, petrous apicitis with erosions of tegmen tympani, and petrous apex. Other findings included bony dehiscences and thinning of left calvaria. Tympanomastoid exploration showed herniated brain and cerebrospinal fluid leak through tegmen tympani, which was closed with temporalis fascia graft. Herein, we report a rare presentation of petrous and tegmen erosion along with aplasia cutis congenita and discuss the challenges in diagnosis and management.

Successful treatment of orbital Langerhans cell histiocytosis with stereotactic radiosurgery: A case report and literature review

Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasm arising from the proliferation of pathologic Langerhans cells. LCH has a spectrum of presentations predominantly affecting male pediatric patients. As LCH is a relatively uncommon diagnosis, there is no standard of care for treatment of the disease and treatment is based largely on clinical judgment, lesion characteristics, and symptoms at presentation. Here we present a case of unifocal, isolated orbital LCH in a 19-year-old young man treated initially with surgical resection. Follow-up imaging 2 months later demonstrated significant regrowth of the mass and no other sites of disease. The recurrent orbital disease was treated with stereotactic radiosurgery (SRS) to 7 Gy in one fraction. Near complete resolution of the mass was achieved with no recurrence after 1.5 years of follow-up. SRS for treatment of orbital LCH is a novel treatment not previously described in the literature which may provide benefit in select cases.

Pilot study to estimate the safety and effectiveness of hydroxyurea and methotrexate recurrent langerhans cell histiocytosis (LCH-HU-pilot)

This study was a non-blinded, multicenter, single-arm study. Recurrent (relapsed) LCH is defined as the appearance of new lesions or the enlargement of preexisting lesions due to LCH. In this study, all patients received hydroxyurea, and if the treatment response was unsatisfactory, methotrexate was added. The duration of treatment was 48 weeks. The primary endpoint was the rate of non-active disease achievement, which was 24 weeks after initiating hydroxyurea administration. No active disease is defined as the resolution of all the signs and symptoms related to LCH.

Diagnosis of Langerhans cell histiocytosis on cytological examination of cerebrospinal fluid: Report of the first case

Langerhans cell histiocytosis (LCH) is a disease of unknown etiology characterized by a proliferation of histiocytic cells resembling dendritic Langerhans cells. LCH can be unifocal or multifocal, with one- or many-organ involvement. The serous fluids are rarely involved. Cytological diagnosis of LCH is possible and relies on recognition of the typical cytomorphological features and subsequent immunocytochemical confirmation. Given the possibility of multisystem involvement, after diagnosing LCH it is necessary to carry out staging exams such as a bone survey, abdominal ultrasound, complete blood count, screening for diabetes insipidus and pulmonary function tests. We present the first case of LCH where the diagnosis was reached on cytological material from the cerebrospinal fluid. To the best of our knowledge, this is the first such case reported in the international literature to date. The morphological and immunocytochemical characteristics of our case are described, and the relevant literature is reviewed.

Secondary Acquired Cholesteatoma in Langerhans Cell Histiocytosis Patient

Langerhans cell histiocytosis (LCH) is a multi-faceted disease defined by the accumulation of dendritic cells in various organs with characteristics similar to the epidermal Langerhans cells and can affect any organ of the body. It is most commonly seen in young adults and children. Cholesteatoma is a congenital or acquired condition and is categorized into primary and secondary cholesteatomas. Only a few reported cases of primary or secondary cholesteatoma have been reported among patients treated for temporal bone LCH. We report a case of secondary acquired cholesteatoma in a six-year-old girl after five years of her LCH treatment. The patient initially presented with ear discharge and aural polyp which did not improve with medical management. A computed tomography scan of the mastoid showed a left middle ear cavity and temporal bone lesion with bony erosions and total obliteration of the left external auditory canal. The patient underwent multiple biopsies, and a histopathological evaluation confirmed the diagnosis of cholesteatoma. The diagnosis of LCH can be difficult due to variable clinical manifestations. Involvement of the ear as resemblance to other diseases such as mastoiditis and chronic otitis media are quite common. Computed tomography scan and biopsy are reliable tools for diagnosis. Cholesteatoma following LCH remains a rare entity, hence, critical examination at follow-up visits is needed. Surgery remains the treatment of choice for cholesteatoma patients.

Prevalence of the BRAF V600E mutation in Greek adults with Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasia with a broad spectrum of clinical manifestations. The activation of the MAP kinase pathway plays an integral role in its pathogenesis with genetic alterations found in the majority of cases that most frequently involve a somatic mutation of the oncogenic BRAF^V600E variant. In this study we investigated the prevalence of the BRAF^V600E mutation and its clinical relevance in adult Greek patients with LCH. Among 37 patients studied, the BRAF^V600E mutation was identified in 12 out of 31 (38.7%), whereas in six patients (19.3%) the results were in conclusive. The presence of the mutation did not correlate with age at diagnosis, organ involvement, disease extent, response to initial treatment, development of diabetes insipidus and relapse risk. In our series the prevalence of the BRAF^V600E mutation is at the lower range of the relative percentage found in children, but in line to that obtained in previous studies of adult patients with LCH that have found an up to 50% prevalence of the BRAF^V600E mutation in these patients. Further studies with a larger number of adults are needed to identify the exact prevalence of mutations in the RAS-RAF-MEK-ERK pathway and their role on clinical parameters and disease outcomes.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2022.2029988 .

An in-depth discussion of cholesteatoma, middle ear Inflammation, and langerhans cell histiocytosis of the temporal bone, based on diagnostic results

OBJECTIVE

This study aimed to conduct an in-depth investigation of the learning framework used for deriving diagnostic results of temporal bone diseases, including cholesteatoma and Langerhans cell histiocytosis (LCH). In addition, middle ear inflammation (MEI) was diagnosed by CT scanning of the temporal bone in pediatric patients.

DESIGN

A total of 119 patients were included in this retrospective study; among them, 40 patients had MEI, 38 patients had histology-proven cholesteatoma, and 41 patients had histology-proven LCH of the temporal bone. Each of the 119 patients was matched with one-third of the disease labels. The study included otologists and radiologists, and the reference criteria were histopathology results (70% of cases for training and 30% of cases for validation). A multilayer perceptron artificial neural network (VGG16_BN) was employed and classified, based on radiometrics. This framework structure was compared and analyzed by clinical experts according to CT images and performance.

RESULTS

The deep learning framework results vs. a physician's diagnosis, respectively, in multiclassification tasks, were as follows. Receiver operating characteristic (ROC) (cholesteatoma): (0.98 vs. 0.91), LCH (0.99 vs. 0.98), and MEI (0.99 vs. 0.85). Accuracy (cholesteatoma): (0.99 vs. 0.89), LCH (0.99 vs. 0.97), and MEI (0.99 vs. 0.89). Sensitivity (cholesteatoma): (0.96 vs. 0.97), LCH (0.99 vs. 0.98), and MEI (1 vs. 0.69). Specificity (cholesteatoma): (1 vs. 0.89), LCH (0.99 vs. 0.97), and MEI (0.99 vs. 0.89).

CONCLUSION

This article presents a research and learning framework for the diagnosis of cholesteatoma, MEI, and temporal bone LCH in children, based on CT scans. The research framework performed better than the clinical experts.

Erdheim Chester Disease - Unusual Presentation with Isolated Skeletal Lytic Lesions

Introduction

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis (LCH) of unknown origin that was first described in 1930. Since then, almost 600 cases have been reported worldwide. Even though this disease primarily affects the bone, it has a varied clinical spectrum of presentation ranging from asymptomatic bone lesions to multisystem involvement. Owing to its protean manifestations ECD is often misdiagnosed or diagnosed late.

Case Report

We present a 48-year-old female with a long long-standing history of recurrent bone lesion of the tibia and multiple trivial trauma fractures of long bones. Recently, she also developed a persistent headache and painful swelling of the right shoulder and left hip joint. Radiographs revealed multiple lytic and lytic sclerotic lesions. With the probable diagnosis of LCH, she underwent biopsy which revealed features characteristic of ECD.

Conclusion

This case highlights the fact that histopathological confirmation is the key to distinguish various types of histiocytic neoplasms. Overlapping clinical and radiological features with atypical manifestations can occur in both LCH and ECD and does not rule out either of them.

Histopathology of intestinal villi in neonatal and paediatric age: main features with clinical correlation - Part II

In this paper, we will continue the description of histological findings of infantile and paediatric small bowel alterations with the main clinical pictures and differential diagnosis. We emphasise once again the need to evaluate the biopsies in an adequate clinical contest and with a systematic approach, including epithelial alterations, lamina propria changes, mucosal architecture, and the distribution of inflammation, together with other morphological signs more specific of certain diseases. We describe the histological findings of coeliac and Crohn’s disease, gastrointestinal food allergic diseases, Langerhans cell histiocytosis, nutritional deficiencies and infections. Finally, we suggest the principal issues in the drafting the pathological report for appropriate interpretation and usefulness in clinical practice.

Pseudomalignancies in Children: Histological Clues, and Pitfalls to Be Avoided

The term “pseudomalignancy” covers a large, heterogenous group of diseases characterized by a benign cellular proliferation, hyperplasia, or infiltrate that resembles a true malignancy clinically or histologically. Here, we (i) provide a non-exhaustive review of several inflammatory skin diseases and benign skin proliferations that can mimic a malignant neoplasm in children, (ii) give pathologists some helpful clues to guide their diagnosis, and (iii) highlight pitfalls to be avoided. The observation of clinical–pathological correlations is often important in this situation and can sometimes be the only means (along with careful monitoring of the disease’s clinical course) of reaching a firm diagnosis.

Long-term outcome, clinical course and treatment approaches of paediatric langerhans cell histiocytosis: A greek reference centre report

AIM

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia with diverse clinical behaviour. In this article, we studied the clinical course, management and long-term outcomes of a paediatric cohort treated by our reference centre.

METHODS

We retrospectively studied 66 children with LCH, consecutively diagnosed by a Greek reference centre from 1974 to 2020.

RESULTS

The patients had a median age of 3.9 (range 0.0-15.9) years, 39 and 6 patients were diagnosed with unifocal or multifocal single system disease and 14 and 7 had multisystem disease with or without risk organ involvement. No late occurrence of clinical neurodegenerative disease or diabetes insipidus were observed at a median follow-up period of 4.1 (range 0.5-27.7) years. The 10-year event-free survival and overall survival were 65.0% and 90.3% and improved significantly over a 45-year period. Survival was superior in single system than multisystem cases. BRAF V600E mutation was found in 8/14 tested patients. Reactivation occurred in 12/66 patients (18.2%); 11 achieved remission and one patient died after a second relapse.

CONCLUSION

LCH survival rates significantly increased in our cohort over time. Reactivation occurred in 18.2% patients, but no late neurodegeneration was found. The prognostic value of single system disease status vs. multisystem LCH was confirmed.

Findings encountered in percutaneous cholangiography in a case of post-transplant recurrence of hepatic Langerhans cell histiocytosis with biliary involvement

This case report describes a four-year-old boy who presented with the diagnosis of LCH with liver involvement. This required a living-related liver transplant one year later. The primary disease recurred in the transplanted liver 6 months post-transplant and led to progressive biliary dilatation. A percutaneous trans-hepatic cholangiogram was performed five years after transplant, showing a pattern of multifocal biliary duct strictures mimicking the pattern of primary sclerosing cholangitis and a stenosis of the biliary-enteric anastomosis. Despite management with an internal-external biliary drain, the stenosis of the biliary-enteric anastomosis evolved to an occlusion one year after drain removal. This was associated with progression of the changes in the biliary tree, this time associated with significant saccular dilatations secondary to the multiple areas of stenosis. Due to these findings and progressive deterioration of the function of the graft, the patient required re-transplantation. This report illustrates the findings in imaging of the biliary tree secondary to the recurrence of LCH after liver transplantation, which may help to recognize this complication to physicians facing a similar clinical scenario.

Adult Langerhans Cell Histiocytosis Diagnosed by Biopsy of the Skull Tumor Generated after Craniotomy

Langerhans cell histiocytosis (LCH) is a disease characterized by the proliferation of Langerhans cells. Most cases of LCH occur in children, although it can be seen in adults as well. We encountered an adult case of LCH. A 44-year-old woman who was diagnosed as diabetes insipidus underwent a magnetic resonance imaging (MRI) of the head which revealed sellar and suprasellar gadolinium-enhanced mass. Prolactin level was high and cabergoline was prescribed. The size of this mass had reduced, so we supposed the tumor was prolactinoma. However, after 4 years of observation, it had increased once again. The biopsy of pituitary stalk lesion was performed via transcranial approach. The histological diagnosis was initially gangliocytoma. The patient complained of back pain after surgery. Three months after the biopsy, a computed tomography (CT) scan revealed multiple osteolytic lesions throughout the entire body. One of the osteolytic lesions of the skull was removed to determine the diagnosis. The pathological examination of the skull led to a diagnosis of LCH. We concluded retrospectively that the lesion of the pituitary stalk was LCH mimicking gangliocytoma though classical pathological findings were not obtained. In conclusion, LCH should be considered as a differential diagnosis in adult cases of diabetes insipidus with hypothalamic-pituitary lesion.

Langerhans Cell Histiocytosis of the Orbit: Spectrum of Clinical and Imaging Findings

OBJECTIVE

To evaluate the clinical and imaging characteristics of orbital lesions of pediatric Langerhans cell histiocytosis (LCH).

STUDY DESIGN

A retrospective analysis of clinical data and central review of magnetic resonance imaging scans in patients with LCH, enrolled into one of the consecutive international trials LCH I-III, or submitted for a second opinion between 1994 and 2015.

RESULTS

Data from 31 children (34 involved orbits) were analyzed. Orbital LCH was the only disease manifestation in 15, part of a multifocal skeletal in 5, or a multisystem LCH in 11 patients. Orbital LCH was part of the initial disease presentation in 23 or developed at relapse in 8 cases. Orbital involvement was unilateral in 28 and bilateral in 3 patients (34 affected orbits). Proptosis was present in 9 patients. Frontal and zygomatic bone were most commonly affected. All orbital lesions were extraconal. Associated extraorbital imaging findings were dural tail sign in 19, neurodegeneration in 8, and hypothalamic-pituitary mass in 3 patients. Sixteen patients (52%) had at least 1 documented disease relapse. Permanent consequences were prominent proptosis in 1, diabetes insipidus in 8, growth hormone deficiency in 2, radiologic neurodegeneration in 8, and clinical neurodegeneration in 3 patients.

CONCLUSIONS

Predominantly unilateral orbital LCH can be the only disease manifestation or part of a disseminated disease. Orbital lesions in LCH are exclusively extraconal, typically located at the roof and the lateral wall of the orbit. The optimal treatment approach of unifocal LCH of the orbit remains controversial and warrants a prospective evaluation.

[Recurrent vulvar rashes in a girl aged 22 months for more than half a year]

A girl, aged 22 months, attended the hospital due to recurrent vulvar rashes for more than half a year. Skin biopsy showed Langerhans cell histiocytosis, and evaluation of systemic conditions showed no systemic involvement. Therefore, the girl was diagnosed with Langerhans cell histiocytosis (skin type). In conclusion, for rashes on the vulva alone, if there are no specific clinical manifestations, the possibility of Langerhans cell histiocytosis should be considered after molluscum contagiosum, sexually transmitted diseases, and Fordyce disease are excluded.

Case Report: Two Infant Cases of Langerhans Cell Histiocytosis Involving the Digestive Tract

Langerhans cell histiocytosis (LCH) is a rare disease with uncertain etiology. Langerhans cell histiocytosis with involvement of the gastrointestinal tract is rare and is typically identified in pediatric patients with systemic disease. The present study reports two infantile cases of LCH who initially presented with diarrhea, hematochezia, and rash and were histologically missed on the original examination of the colonic biopsy sections. The diagnosis of LCH was later verified through immunohistochemistry. By combining our experience and previous reports, the multiple hemorrhagic spots of the colorectal mucosa and narrowness and erosion of the distal duodenum might be suggestive manifestations of gastrointestinal involvement in LCH on endoscopic examination. This might be helpful for the early recognition of the disease.

Concurrent Langerhans Cell Histiocytosis and Autoimmune Hepatitis: A Case and Review of the Literature

Autoimmune hepatitis (AIH) and Langerhans cell histiocytosis (LCH) are two independently rare disease processes that can have similar presentations. We present a unique, complex case that required a multidisciplinary approach to ultimately diagnose and treat the patient. A 20-year-old male with no significant history presented with worsening jaundice, diffuse, pruritic rash, and abdominal pain over one month. On admission, the patient's labs showed significantly elevated liver function tests (LFTs), eosinophilia, and anemia. The exam was notable for diffuse lymphadenopathy (LAD), hepatosplenomegaly, and a diffuse, non-blanching, morbilliform rash. Interdisciplinary workup was notable for positive anti-smooth muscle antibody (ASMA) and anti-neutrophilic antibody (ANA). A liver biopsy showed severe inflammation with interface activity, consistent with AIH. A lymph node (LN) biopsy showed findings consistent with LCH, including histiocyte clusters. He was started on high-dose steroids with LAD/LFT improvement; yet, his course was complicated by a gastrointestinal (GI) bleed requiring a hemicolectomy. The patient was transferred to a larger referral center where he continued to improve with steroids and was ultimately discharged. This case was notable for an LN biopsy showing histiocyte clusters with reniform nuclei, nuclear grooves, and eosinophils with immunohistochemical stains positive for S-100, CD1a, fascin, langerin, CD45, and CD68, consistent with LCH. The resected colon showed atypical histiocyte proliferation positive for fascin, CD4, and CD68. Other findings, including elevated LFTs, ASMA, and a liver biopsy showing inflammation with interface activity, eosinophils, plasma cells, and characteristic fibrosis, supported a diagnosis of AIH. In either case, steroids were indicated.

Delayed Diagnosis of Langerhans Cell Histiocytosis Presenting With Thyroid Involvement and Respiratory Failure: A Pediatric Case Report

Langerhans cell histiocytosis (LCH) is a rare disease with localized to disseminated clinical features. Thyroid involvement in LCH is rare and presenting as either a single-organ or multisystem disease, it is usually misinterpreted as another thyroid disorder. Therefore, the LCH diagnosis is often delayed. We report a pediatric case of LCH with thyroid involvement as the initial clinical manifestation progressing to respiratory failure. Clinicians should note insidious extrathyroidal laboratory abnormalities and consider infiltrative thyroid diseases, such as LCH. Systematic clinical and laboratory investigations are needed to prevent delayed diagnosis because the classic features of LCH may become evident only over time.

BRAF V600E-Positive Congenital Multisite Langerhans Cell Histiocytosis

Congenital Langerhans cell histiocytosis (LCH) usually manifests as a disease limited to the skin, with self-healing characteristics; however, in some cases, it may be a more severe entity, with multisystemic expression and poor prognosis. We present the case of a patient diagnosed with multisystemic congenital LCH, with the presence of the BRAF V600E mutation, with a severe form of the disease, with risk organ compromise, and manifestations of resistance to chemotherapy. This case is a challenge due to the disease's biologically aggressive behavior in this patient. It presents unique treatment difficulties as a result of inherent resistance to conventional therapy and uncertain response to BRAF inhibitors.

Isolated Cutaneous Langerhans Cell Histiocytosis Presenting in an Adult Male

Langerhans cell histiocytosis (LCH) is an infrequent clonal proliferative disorder of myeloid dendritic cells. It has a wide variety of cutaneous manifestations and retains the possibility of systemic implications. Because LCH is predominantly a disease of childhood, there are well-established clinical definitions, as well as guidelines regarding workup and treatment, in the context of pediatric disease. Here we present a case of isolated cutaneous LCH in an adult male, followed by a discussion of our diagnostic plan and treatment course. The patient exhibited a small, excoriated, yellow papule on his inferior forehead during a skin examination. The specimen underwent tangential shave biopsy; histopathologic evaluation with appropriate immunohistochemical staining confirmed a diagnosis of cutaneous LCH. After thorough investigation via serologic and imaging diagnostics, we confirmed isolated cutaneous disease. The patient underwent wide local excision (WLE) with no evidence of recurrence. It is crucial to appropriately screen all patients diagnosed with cutaneous LCH for internal organ involvement. The authors aim to highlight the need for further investigations to ultimately dictate standardized management and treatment for isolated cutaneous LCH in the adult population.

Intra-Lesional Medicaments for the Management of Intra-Osseous Lesions of Maxilla and Mandible - Systematic Review

Aims and Objectives:

This study aimed to review the success or remission of intralesional medicaments in the management of intraosseous lesions in the oral cavity.

Materials and Methods:

A comprehensive search was performed in two databases (PubMed and Scopus). Research articles, case reports, case series, and clinical trials were included. Review articles, lesions not involving the bone, incomplete reporting, any other treatment other than intralesional medicaments to treat intraosseous bone lesions, publications without any treatment, and letter to editor were excluded. Data on remission (complete, partial, or no remission), details and regimen of the intervention, number of participants, and follow-up in months were recorded.

Results:

A total of 653 publications were available for title and abstract screening after the removal of duplicates. Seven articles were excluded, which were not in English. After title and abstract screening, a total of 88 publications were available for full-text screening. Fifty-five articles were included in qualitative synthesis. A total of 168 patients from 55 publications were evaluated. Minimum follow-up was 1 month and maximum was 264 months. More than two-third (n = 38) of the publications were case reports on single patient. More than two-third (n = 38) of the publications had complete remission.

Conclusion:

Intralesional medications have shown variable success rates. Extensive lesions may undergo intralesional medications followed by surgical management.

Spinal epidural involvement in adult Langerhans cell histiocytosis (LCH): A case report

RATIONALE

Spinal involvement in adult Langerhans cell histiocytosis (LCH) is rare, and epidural involvement is unusual. LCH is mostly indistinguishable from other spinal lesions such as infection, lymphoma, and metastasis. So, it could be easily misdiagnosed without suspicion.

PATIENT CONCERNS

We report a case of a 33-year-old man who complained of gait disturbance with weakness in both legs and severe back pain.

DIAGNOSES

A continuous enhancing epidural lesion with cord compression from the T7 to L1 level was detected in magnetic resonance imaging. Laboratory analysis indicated the possibility of spinal infectious disease. We assumed that the lesion could be tuberculous spondylitis.

INTERVENTIONS AND OUTCOMES

The patient underwent posterior laminectomy with marginal excision of the epidural mass to relieve cord compression. Pathological examination confirmed the diagnosis of LCH. The 12-month follow-up evaluation revealed that the patient was neurologically intact and had no gait disturbance.

LESSONS

This case report presents a patient with epidural LCH of the thoracic spinal cord, which can mimic spinal infections such as tuberculous spondylitis with abscess formation. Therefore, LCH could be considered as a possible diagnosis when a patient presents with features of infectious spondylitis with vertebral involvement.

Clinical Characteristics of Pediatric Patients With Sellar and Suprasellar Lesions Who Initially Present With Central Diabetes Insipidus: A Retrospective Study of 55 Cases From a Large Pituitary Center in China

Purpose: To increase knowledge for the early differential diagnosis and accurate therapeutic strategies for pediatric patients with sellar or suprasellar region (SSR) lesions who initially present with central diabetes insipidus (CDI). Methods: This is a retrospective review of 55 pediatric patients (≤14 years old) with identified lesions in the SSR who initially presented with CDI at a large pituitary center between 2012 and 2018. The following data were summarized: demographic, clinical, endocrine, and neuroimaging data, intraoperative findings, histopathological findings, treatments, and prognosis. Results: In our group, the etiologies of the SSR lesions included germ cell tumors (GCTs, 74.5%), Langerhans cell histiocytosis (LCH, 18.2%), and craniopharyngioma (CP, 7.3%). Almost all patients (50/55, 90.9%) showed anterior pituitary dysfunction [multiple axes dysfunction (38), and isolated axis dysfunction (14)], while the GH/IGF-I axis was the most affected. Most GCT patients presented with various clinical manifestations besides CDI and had elevated β-HCG, whereas LCH and CP patients mostly presented few non-specific symptoms besides CDI and most had normal level tumor markers. Sellar MRI demonstrated that posterior pituitary bright spot disappearance occurred in all patients, and pituitary stalk thickening was observed in 96.7% of patients. Treatment varied due to the different etiologies of the SSR lesions. After follow-up for 35.4 ± 20.2 months, the proportions of patients who needed AVP (arginine vasopressin) for GCT, LCH, and CP were 86.5, 100, and 75%, respectively, and the proportions of patients who needed HRT were 89.2, 50, and 75%, respectively. Conclusion: For pediatric SSR lesions that first manifest as CDI, we should comprehensively consider clinical characteristics and imaging features to aid in their early differential diagnosis. Tumor markers and surgical histopathology are also great complements for the differential diagnosis. Additionally, various treatment strategies should be adopted according to different causes to improve the child's prognosis and quality of life.

Congenital self-healing langerhans cell histiocytosis: clinical and pathological characteristics

INTRODUCTION

Congenital Self-Healing Langerhans Cell Histiocytosis (CSHLCH) is rare, characterized by cutaneous lesions at birth or in the neonatal period, and absence of systemic lesions.

MATERIALS AND METHODS

Skin biopsy was performed and the histologic examination of the skin section, routinely stained with hematoxylin-eosin. Paraffin sections were stained by immunohistochemical study which were carried out according to the manufacturer's protocols.

RESULT

Seven cases of CSHLCH were recruited. 28.6% (2/7) of the cutaneous lesions were multiple, 71.4% (5/7) were solitary. Skin biopsy was performed and the histologic examination of the skin section, routinely stained with hematoxylin-eosin. Microscopically, in the dermis, a dense infiltrate of histiocytic cells mixed with numerous eosinophils. These histiocytes were immunohistochemically positive for CD1a and S-100. All of the cutaneous lesions regress spontaneously, and lack of systemic involvement, the final diagnosis of Congenital Self-Healing Langerhans Cell Histiocytosis were made. No recurrence had been observed.

CONCLUSION

The cutaneous lesions of CSHLCH may regress spontaneously. Spontaneous resolution of cutaneous lesions and lack of systemic involvement are essential for the diagnosis of CSHLCH. It needs long-term follow-up.

Cervical langerhans cell histiocytosis mimicking cervical tuberculosis: A Case report

RATIONALE

Langerhans cell histiocytosis (LCH) involving adult cervical vertebrae is relatively rare clinically.

PATIENT CONCERNS

An 18-year-old male patient exhibited a 1-month history of neck pain, restricted neck mobility, and numbness and weakness of both upper limbs. The patient reported no pain at other sites, exhibited no fever or night sweats, and was unable to recall any recent injury.

DIAGNOSES

On the basis of the radiological features of the lesion and laboratory tests, there was a high possibility that the patient had a tuberculosis lesion. Postoperative GeneXpert and Mycobacterium tuberculosis (MTB) culture results showed MTB negative. Postoperative pathological results showed: (Cervical 4 vertebrae) LCH.

INTERVENTIONS

Our department did an anterior approach operation. The patient was treated with prednisone combined with vincristine after operation.

OUTCOMES

The patient was discharged from the hospital with complete remission of cervical pain and rapid relief of neurological symptoms.

LESSONS

Computed tomography-guided biopsy of lesion tissue must be performed when a suspected infection occurs in young patients. If possible, the lesion tissue obtained during the operation should be cultured and pathologically examined for early diagnosis.

[Langerhans cell histiocytosis involving the oral and maxillofacial region: an analysis of 12 cases]

OBJECTIVE

To study the clinical features of Langerhans cell histiocytosis (LCH) involving the oral and maxillofacial region in children.

METHODS

A retrospective analysis was performed for the clinical data of 12 children with LCH involving the oral and maxillofacial region who were hospitalized and treated from September 2012 to September 2017, including clinical manifestations, pathological features, treatment and prognosis.

RESULTS

Of the 12 children, 8 (67%) had multiple system involvement and 7 (58%) had the involvement of organs at risk. Bone was the most common affected site (11 children, 92%), among whom 7 children had the involvement of the mandible. Oral soft tissue involvement manifested as gingival ulcer or hyperplasia in 4 children, loose teeth in 5 children, oral mucosal lesions in 2 children, and nodular lesions in 1 child. Pathological examination showed positive CDla in 11 children and positive CD207, CD68, S-100, and LCA in 12 children. Surgery combined with chemotherapy was the major treatment method, and surgical resection alone was performed for focal lesions. After treatment, 11 children were cured or improved and 1 gave up treatment and was lost to follow-up. No recurrence was observed.

CONCLUSIONS

LCH children with oral and maxillofacial involvement often have the involvement of multiple systems and organs at risk, with the mandible as the most common affected site. These children may also have the involvement of gingiva, oral mucosa and teeth. Surgery combined with chemotherapy is the major treatment method, and the patients generally have a good prognosis without recurrence.

Characteristic Reconstitution of the Spinal Langerhans Cell Histiocytosis in Young Children

BACKGROUND

Pediatric Langerhans cell histiocytosis (LCH) often results in vertebral compression fracture. However, few reports have reported vertebral remodeling during the course of LCH. We aimed to investigate the longitudinal reconstitution and transformation of the affected vertebrae and the adjacent structures in young children with spinal LCH.

METHODS

We recruited 13 patients, including 16 affected vertebrae, diagnosed with LCH via biopsy. The average age at first visit was 3.6 years. The average follow-up period was 10.2 years. Vertebral lesions involved L2 in 3 cases; T12, L1, or L5 in 2 cases; and C4, C5, C7, T5, T8, T9, or L3 in 1 case. We measured the ratios of the height of the affected vertebra and 1 vertebra above the affected one to that of the second vertebra above the affected one, local kyphotic angles, and the ratio of the height of the center of the adjacent disk to that of one disk above it.

RESULTS

The collapse of the affected vertebra was most severe after 1 year of disease onset. The rate of reconstitution accelerated at 2 years or later of disease onset. The recovery speed of the anterior wall was faster than that of the center height. While the height of the affected vertebrae was restored, the thickness of the adjacent disk also increased. Further, the height of the adjacent vertebrae increased in a similar manner. The average local kyphosis angle shifted to lordosis within the first 3 years.

CONCLUSIONS

The heights of not only the disk but also the adjacent vertebra increased during the vertebral collapse phase in pediatric spinal LCH patients. These transformations may affect the realignment of the sagittal spinal balance at the earlier stage of the disease. During the collapse phase, the heights of the adjacent vertebrae and disks increase but after the affected vertebrae reconstituted, the augmentation of adjacent vertebrae and disks diminished.

LEVEL OF EVIDENCE

Level IV.

Infiltrating the Heart and Kidney: A Rare Pediatric Case of Multisystem Langerhans Cell Histiocytosis from Pakistan

Langerhans cell histiocytosis (LCH) is a rare, clonal disease of the monocyte-macrophage system, varying in its clinical presentation from mere self-healing skin and bone lesions to life-threatening multi-system disease. In descending order of frequency, the disease is known to involve the skeleton, skin, lymph nodes and lesser often, the liver, spleen, lungs, hematopoietic and central nervous systems. Here, we present a pediatric case of multi-system LCH in a five-year-old child, unique in its evident cardiac and renal involvement alongside other organ systems and important in how the diagnosis was aided by a fine needle aspiration cytology instead of the costlier histopathological procedures, in a setting with limited resources.

Langerhans cell histiocytosis complicated with hemophagocytic lymphohistiocytosis in a boy with a novel XIAP mutation: A case report

RATIONALE

X-linked lymphoproliferative syndromes (XLPs) are rare, yet often fatal primary immunodeficiency diseases, which rarely manifest as Langerhans cell histiocytosis (LCH) complicated with hemophagocytic lymphohistiocytosis (HLH). Clinical data of a case of XLP-2 manifesting as LCH complicated with HLH was retrospectively analyzed to determine the etiology and causal gene.

PATIENT CONCERNS AND DIAGNOSIS

The diagnosis of multisystem LCH was confirmed by skin biopsy and other examinations in a 13-month boy with recurrent ear discharge, fever and hemorrhagic papules for 3 months. A good therapeutic response to LCH-III protocol-directed induction chemotherapy was achieved but unremitting HLH developed 6 weeks after the initiation of induction chemotherapy. To identify possible underlying genetic causes, gene mutation analysis was undertaken. A novel XIAP gene mutation (c.99delT, p.F33fsX37) was documented.

INTERVENTIONS

After the diagnosis of HLH had been confirmed, HLH-2004-directed chemotherapy was instituted.

OUTCOMES

The clinical condition of the patient had become progressively deteriorating after 8-week chemotherapy of HLH-2004 protocol, requiring frequent infusions of RBC suspensions and apheresis platelets. His parents decided to receive no further therapy, and the patient died soon after discharge.

LESSONS

Meticulous laboratory investigations including genetic studies should be undertaken in young children with LCH complicated with HLH and poor therapeutic response.

A novel fusion gene PLEKHA6-NTRK3 in langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is the most common histiocytosis with constitutive activation of the RAS–RAF–MEK–ERK (MAPKinase) cell signaling pathway. We analyzed 89 cases of BRAF and MAP2K1 mutations by Sanger sequencing, of which 18 cases showed that these two gene mutations are negative. Whole genome sequencing of suitable specimens in these negative cases revealed a translocation from the 3 intron of PLEKHA6 to the 13 intron of NTRK3 in one case. We identified that this translocation could cause a novel fusion mutation, PLEKHA6‐NTRK3. Overexpression of the PLEKHA6‐NTRK3 mutant in NIH 3T3 cells enhanced MAPKinase pathway activation, promote cell growth. Our result suggested that a new mutation need be included in LCH molecular screening panel to better define its prevalence in LCH.

What's new?

Langerhans cell histiocytosis (LCH) is a rare immune and neoplastic disorder. While it is known as the most common histiocytosis with constitutive activation of the RAS‐RAF‐MEK‐ERK (MAPKinase) cell signaling pathway, its pathogenesis remains obscure. Here, whole‐genome sequencing of BRAF V600E‐negative and MAP2K1‐negative LCH cases revealed a translocation from the intron 3 of PLEKHA6 to the intron 13 of NTRK3 in one patient, identifying a novel fusion mutation. Overexpression of PLEKHA6‐NTRK3 in vitro enhanced MAPKinase pathway activation, promoting cell growth. The results support the inclusion of the fusion mutation in LCH molecular screening panel to better define its prevalence in patients.

[BRAF-V600E mutation and its clinical significance in children with Langerhans cell histiocytosis]

OBJECTIVE

To investigate the clinical significance of BRAF-V600E mutation in children with Langerhans cell histiocytosis (LCH).

METHODS

Real-time fluorescence quantitative PCR was used to detect BRAF-V600E mutation in paraffin-embedded tissue samples from 26 children with LCH. A retrospective analysis was performed for the association of BRAF-V600E mutation with clinical features and prognosis of children with LCH.

RESULTS

Of the 26 children, 25 received standard chemotherapy, with a 2-year overall survival (OS) rate of 100% and a 2-year event-free survival (EFS) rate of 88%. Of the 26 pathological samples, 18 (70%) came from bone tissue, and the positive rate of BRAF-V600E mutation reached 50% (13/26). The positive rate of BRAF-V600E gene mutation was not associated with age, sex, affected organ, clinical classification, early treatment response, recurrence, and 2-year OS and EFS rates of the children with LCH (P>0.05), but it was associated with clinical grouping of LCH (P<0.05).

CONCLUSIONS

Children with LCH tend to have a high OS rate and a high incidence rate of BRAF-V600E mutation. BRAF-V600E mutation is associated with clinical grouping of LCH.

Langerhans cell histiocytosis with hemorrhagic uveitis and exudative retinal detachment

Bilateral intraocular involvement in Langerhans cell histiocytosis (LCH) is uncommon. A 15-year-old boy presented with painless decreased vision in right and painful left red eye of 2 weeks duration. Visual acuity was 20/500 and 20/200, respectively. A fixed dilated pupil with exudative retinal detachment was present in the right eye and hemorrhagic iris nodules with hyphema and hypopyon were seen in the left eye. Intraocular pressure was 12 and 31 mmHg, respectively, in each eye. Ocular symptoms were preceded by fever with multiple skin rashes, subcutaneous nodules, and lymph node enlargement. The histopathological examination of skin and lymph node showed histiocytes positive for histiocytic S 100. He was treated with topical steroids and antiglaucoma eye drops along with intravenous vinblastine 6 mg and oral prednisolone (1 mg/kg). Hyphema and hypopyon were resolved, vision improved to 20/320 and 20/80, and intraocular pressure was under control. However, as multisystemic LCH has a poor prognosis, we were unable to save him. Hence, fatal conditions like LCH should also be considered in the differential diagnosis of any hemorrhagic uveitis.

Eosinophilic Granuloma in Jaw Bone: A Pare Pediatric Case Report

Background

Eosinophilic granuloma (EG), one of the three clinical forms of Langerhans cell histiocytosis (LCH), is a benign inflammatory reaction to an unknown etiologic agent. It most commonly occurs in children and young adults. The most frequently involved bones are the skull, the ribs and the femurs. Alongside the cranium, the maxilla and mandible can also be affected.

Case Details

Herein, we report a case of eosinophilic granuloma in a ten years old boy involving posterior quadrants upper and lower jaws as a destructive lesion involving gingiva, periodontium and alveolar bone. Involvement of other bones is ruled out by nucleotide imaging study.

Conclusion

EG should be considered as a differential diagnosis whenever there is a bony destructive lesion involving alveolar bone of the Jaws. Early diagnosis and surgical intervention will resolve the lesion.

Extensive nail changes in a toddler with multisystemic Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a multisystem disorder involving various organs. Nail changes in LCH are extremely rare. We present this case report of extensive nail changes in an 18-month-old child with multisystem LCH.

Langerhans cell histiocytosis of the thyroid complicated by papillary thyroid carcinoma: A case report and brief literature review

RATIONALE

Langerhans cell histiocytosis (LCH) involves mainly the skin and bone and rarely the thyroid. Meanwhile, papillary thyroid carcinoma (PTC) is the most common subtype of thyroid cancer. Both LCH and PTC could make the thyroid enlarged and hypermetabolic. The coincidence of these 2 events in a patient is rare, and this paper aimed to report such case.

PATIENT CONCERNS

A 40-year-old man presented with polyuria and polydipsia for 5 years. The symptoms had been relieved well by drug therapy for >4 years, until the drugs could not control the symptoms anymore and an extensively enlarged thyroid gland was noticed.

DIAGNOSES

Thyroid ultrasound showed a nodule with microcalcification in the upper right lobe, positron emission tomography/computer tomography scan demonstrated thyroid hypermetabolism, and fine needle aspiration (FNA) revealed PTC. Right lobectomy of the thyroid and cervical lymph node biopsy verified the diagnosis "LCH of the thyroid complicated by PTC."

INTERVENTIONS

The ultrasound-guided FNA biopsy was performed prior to right lobectomy of the thyroid and cervical lymph node biopsy. Postoperative histopathological examination confirmed the diagnosis, after which the patient received adjuvant chemotherapy.

OUTCOMES

After 5 cycles of adjuvant chemotherapy, the patient had been followed up for 2 years. LCH was controlled satisfactorily and there was no significant sign of recurrence or metastasis of PTC.

LESSONS

LCH of the thyroid complicated by PTC is rare. Thyroid involvement should always be considered in the differential diagnosis of LCH patients. Surgery for PTC followed by chemotherapy for LCH may be the suitable treatment.

[Clinical features and prognosis of Langerhans cell histiocytosis in children: an analysis of 34 cases]

OBJECTIVE

To investigate the clinical features and prognosis of children with Langerhans cell histiocytosis (LCH).

METHODS

A retrospective analysis was performed for the clinical data of 34 children with newly diagnosed LCH.

RESULTS

The 34 children had a median age of 14.5 months (range: 22 d to 60 months). Of all 34 children, 23 were aged 0-2 years and 11 were aged >2 years. There were 17 children in the high-risk group and 17 in the low-risk group. Thirty children received chemotherapy, and the 6-week and 12-month overall response rates were 67% (20/30) and 87% (26/30), respectively. The 3-year overall survival (OS) rate was 86%±6% and the 3-year event-free survival (EFS) rate was 64%±9%. Compared with the low-risk group, the high-risk group had significantly lower 6-week chemotherapy response rate (47% vs 87%; P<0.05), 3-year OS rate (72%±12% vs 100%; P<0.05), and 3-year EFS rate (46%±13% vs 82%±9%; P<0.05). There was no significant difference in the 12-month chemotherapy response rate between the high-risk and low-risk groups (80% vs 93; P>0.05). The high-risk group had a recurrence rate of 27% and a mortality rate of 27%. There were no recurrence or deaths in the low-risk group.

CONCLUSIONS

Children with LCH have a high overall survival rate, but the high-risk patient has a low 6-week response rate of induction chemotherapy and poor long-term prognosis.

Langerhans cell histiocytosis associated with lymphoma: an incidental finding that is not associated with BRAF or MAP2K1 mutations

Langerhans cell histiocytosis is characterized by a localized or systemic proliferation of Langerhans cells. BRAF mutations have been reported in 40-70% of cases and MAP2K1 mutations have been found in BRAF-negative cases, supporting that Langerhans cell histiocytosis is a true neoplasm, at least in mutated cases. In a small subset of patients, Langerhans cell histiocytosis is detected incidentally in a biopsy involved by lymphoma. These lesions are usually minute and rarely have been assessed for mutations. We assessed for BRAF and MAP2K1 mutations in seven cases of Langerhans cell histiocytosis detected incidentally in biopsies involved by lymphoma. We performed immunohistochemical analysis for phosphorylated (p)-ERK. There were four men and three women (median age, 54 years; range, 28-84). The biopsies included lymph nodes (n=6) and chest wall (n=1). The lymphomas included five classical Hodgkin lymphoma, one mantle cell lymphoma, and one angioimmunoblastic T-cell lymphoma. All cases were negative for BRAF V600E and MAP2K1 mutations. Nevertheless, three of seven cases showed ERK activation as shown by expression of p-ERK. We performed mutation analysis using a panel of 134 commonly mutated genes (including BRAF and MAP2K1) by next-generation sequencing on three cases, including two cases positive for p-ERK by immunohistochemistry. No mutations were detected in any of the three cases assessed. Six patients received therapy appropriate for their lymphoma. With a median follow-up of 21 months (range, 6-89), no patients developed disseminated or recurrent Langerhans cell histiocytosis. We conclude that lymphoma-associated Langerhans cell histiocytosis is a clinically benign process that is not associated with BRAF V600E or MAP2K1 mutations and, as suggested by others, the designation Langerhans cell hyperplasia may be more appropriate. Nevertheless, the expression of p-ERK in three cases suggests that the RAS-RAF-MAP2K-ERK pathway is activated, perhaps by non-mutational mechanisms induced by the presence of lymphoma or lymphoma-microenvironment interactions.

Severe sclerosing cholangitis after Langerhans cell histiocytosis treated by liver transplantation: An adult case report

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare hematopoietic disorder of unknown pathogenesis. LCH diseases may occur in a single organ or multisystem organ. The patients with multisystem involvement usually have a poor prognosis. Liver involvement in multisystem LCH results in severe complications, such as obvious sclerosing cholangitis (SC) with jaundice.

METHODS

We reported a 31-year-old man developed severe SC due to multisystem LCH and was successfully treated by liver transplantation (LT). In addition, we firstly used tacrolimus and mycofenolate mofetil as immunosuppressants to treat LCH after LT.

RESULTS

We performed the immunosuppressants to deal with the LCH after LT, now the patient is currently well with normal liver function and no evidence of recurrence of LCH for 4 and a half years follow-up.

CONCLUSION

LT should be recommended as an effective treatment for these adults with severe SC due to multisystem LCH. Finally, using tacrolimus and mycofenolate mofetil as immunosuppressants to treat LCH might be favorable to prevent LCH recurrence.

Evaluation of pituitary uptake incidentally identified on 18F-FDG PET/CT scan

The clinical significance of pituitary uptake on routine whole body ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computer tomography (PET/CT) is not completely characterized. We seek to assess the potential differential diagnosis/underlying etiology of pituitary FDG uptake incidentally identified on routine PET/CT scans. A total of 24,007 PET/CT whole body scans in recent 5 years were retrospectively reviewed. Patients with maximum standardized uptake value (SUVmax) > 4.1 in the pituitary glands were identified. Cases with a known history of pituitary disorders were excluded. Nineteen cases were identified with incidental pituitary FDG uptake which all had a final pathological diagnosis/clinical follow up. Among them, there were 9 primary pituitary tumors, with SUVmax ranging from 4.7 to 29.3 (13.6 ± 9.8); 3 metastatic malignancy with SUVmax ranging from 7.3 to 32.3 (16.0 ± 10.6); 3 Langerhans cell histiocytosis (LCH) with SUVmax ranging from 6.0 to 26.0 (15.0 ± 10.2); 1 pituitary lymphocytic hypophysitis with SUVmax of 4.7. Of note, 3 cases with SUVmax of 7.5,7.9 and 9.6 showed no relevant clinical symptoms with negative results on subsequent magnetic resonance (MR) and were counted as benign physiologic uptake. The most common differential diagnosis of incidental pituitary uptake on routine whole body PET/CT scans was primary pituitary tumors, followed by metastatic malignancy, Langerhans cell histiocytosis, and inflammatory lymphocytic hypophysitis. Of note, benign physiologic uptake without corresponding lesions could also occur in our population.

Langerhans cell histiocytosis: therapeutic strategy and outcome in a 30-year nationwide cohort of 1478 patients under 18 years of age

The French national cohort of children with Langerhans cell histiocytosis (LCH) has included 1478 patients since it was established in 1983. LCH therapeutic strategies substantially changed in 1998, so we have divided the cohort into two 15-year periods. Starting in 1998, therapy duration increased from 6 to 12 months, repeated induction therapy was performed in cases showing a poor response to the first induction with vinblastine and steroids, and refractory disease in a risk organ (RO+) was treated with cladribine and cytarabine. A total of 483 (33%) patients were enrolled before 1998, and 995 (67%) after 1998. Five-year survival was 96·6% (95% confidence interval: 95·4-97·5%) overall, improving from 92% pre-1998 to 99% post-1998 (P < 0·001 adjusted to disease extent). This change was supported by an increase in 5-year survival from 60% to 92% in the RO+ group. Survival was particularly associated with cladribine and cytarabine among refractory RO+ patients. Disease reactivation was slightly less frequent after 1998, due to better enrolment of single-system patients, extended therapy duration, and more efficient second-line therapy. The crude rates of endocrine and neurological sequelae (the most frequent sequelae) appeared to improve over time, but this difference was not observed when the analysis was stratified by disease extent.

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.

Ethnicity, race, and socioeconomic status influence incidence of Langerhans cell histiocytosis

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare disease, and its etiology is not well understood. Population-based studies may contribute to etiologic research by defining incidence patterns. This study was designed to evaluate the descriptive epidemiology of disseminated LCH in the United States, using data from population-based cancer registries.

PROCEDURE

We analyzed the incidence and survival of disseminated LCH in children and adolescents (0-19 years) from 18 SEER registries during 2000-2009. Age-standardized incidence rates (ASIR) per million and rate ratios (RR) were calculated by gender, race, ethnicity, age, and socioeconomic variables (crowding, rural/urban, education, and poverty) using the SEER*Stat software 8.0.1. Relative survival (RS) estimates were calculated using Ederer II method.

RESULTS

One hundred forty-five cases of disseminated LCH were recorded; ASIR was 0.70/million per year. Lower ASIR was observed for blacks (vs. whites) (RR = 0.41, 95% CI 0.18-0.81), while higher ASIR was noted for Hispanics (vs. non-Hispanics) (RR = 1.63, 95% CI 1.15-2.29). Risk of LCH was higher in crowded counties (RR = 1.84, 95% CI 1.31-2.58) and also in areas with low educational level (RR = 1.49, 95% CI 1.02-2.22). Five-year relative survival was 90.0% (95% CI 83.0-94.2). Important differences in survival were noted according to gender (male: RS = 96.0 vs. female: RS = 83.4%, P = 0.029) and age (<1 year: RS = 78.5, 1-4 years: RS = 95.6%, 5-19 years: RS = 100%, P = 0.004).

CONCLUSIONS

This population-based study shows significant variations in the incidence of disseminated LCH by race and ethnic group, as well as the influence of socioeconomic factors. These data may provide clues to causation and point toward the need for analytical epidemiologic studies.

Management of diabetes insipidus and adipsia in the child

Central diabetes insipidus (CDI) is a complex and heterogeneous clinical syndrome affecting the hypothalamic-neurohypophyseal network and water balance. A recent national surveillance in Denmark showed a prevalence rate of twenty-three CDI patients per 100,000 inhabitants in five years. The differential diagnosis between several presenting conditions with polyuria and polydipsia is puzzling, and the etiological diagnosis of CDI remains a challenge before the identification of an underlying cause. For clinical practice, a timely diagnosis for initiating specific treatment in order to avoid central nervous system damage, additional pituitary defects and the risk of dissemination of germ cell tumor is advisable. Proper etiological diagnosis can be achieved via a series of steps that start with careful clinical observation of several signs and endocrine symptoms and then progress to more sophisticated imaging tools. This review summarizes the best practice and approach for the diagnosis and treatment of patients with CDI.