Otologic manifestations of Langerhans' cell histiocytosis

Case report: Langerhans cell histiocytosis of the temporal bone in children: Challenging diagnosis of a rare disease with some pitfalls

A 4‐year‐old girl was admitted to hospital with disturbance of balance. After being questioned, parents remembered an otitis with effusion 3 months earlier. CT‐scans revealed destruction of both temporal bones. Initial biopsy showed granulomatous, necrotic inflammation, which led to comprehensive differential diagnoses. A second tissue sample confirmed Langerhans cell histiocytosis.

Otologic Manifestations of Langerhans Cell Histiocytosis: A Systematic Review

OBJECTIVE

To perform a systematic review to investigate common otologic manifestations of Langerhans cell histiocytosis, the incidence of these findings, methods for diagnosis, as well as medical and surgical management.

DATA SOURCES

PubMed/MEDLINE, Embase, and Cochrane Library.

REVIEW METHODS

A search of PubMed/MEDLINE, Embase, and Cochrane Library for all articles published between 1963 to 2020 was performed with variations and combinations of the following search terms: Langerhans cell histiocytosis, eosinophilic granuloma, Letterer-Siwe, Hand-Schüller-Christian, otitis, otologic, ear. A review of the references of all included articles was also conducted.

RESULTS

Sixty-two articles encompassing 631 patients met inclusion criteria. Otologic symptoms at presentation were found in 246 (39%) patients in the reported studies with 48% reporting bilaterality. The mean age was 14.8 years with a male predominance (64%). The most common otologic presenting symptom was otorrhea (46%). A majority had the multisystem variant (52%). The most common treatment modalities were chemotherapy (52%), followed by surgery (50%), systemic steroids (45%), and radiotherapy (31%). Surgery was performed in 75.8% with unisystem involvement and in 50.6% with multisystem involvement. The most effective treatments included radiotherapy (56% success rate, 17% of treated patients), systemic steroids (44% success, 20% treated), chemotherapy (41% success, 21% treated), and surgical modalities (36% success, 19% treated).

CONCLUSIONS

Otologic manifestations that occur with the multisystem variant or are at high risk for central nervous system involvement necessitate systemic treatment. For unifocal lesions, surgery is recommended. Lastly, radiotherapy should be reserved for extensive lesions involving vital structures or presenting in older patients.

Rare Diseases of the Middle Ear and Lateral Skull Base

Otalgia, otorrhea and hearing loss are the most common ear-related symptoms that lead to the consultation of an otolaryngologist. Furthermore, balance disorders and affections of the cranial nerve function may play a role in the consultation. In large academic centres, but also in primary care, the identification of rare diseases of the middle ear and the lateral skull base is essential, as these diseases often require interdisciplinary approaches to establish the correct diagnosis and to initiate safe and adequate treatments. This review provides an overview of rare bone, neoplastic, haematological, autoimmunological and infectious disorders as well as malformations that may manifest in the middle ear and the lateral skull base. Knowledge of rare disorders is an essential factor ensuring the quality of patient care, in particular surgical procedures. Notably, in untypical, complicated, and prolonged disease courses, rare differential diagnoses need to be considered.

Temporal Bone Langerhans Cell Histiocytosis: An Uncommon Bilateral Presentation

Langerhans cell histiocytosis (LCH) is a rare condition that presents clinically in various ways. The cause and subsequent development of LCH are idiopathic and not fully understood. This disease is mainly seen in childhood. It is rare to have bilateral temporal bone LCH as the initial presentation. LCH can affect many organs. However, the bilateral involvement of the temporal bone is very uncommon. Therefore, we believe documenting cases of this presentation can lead to a better understanding of the epidemiology and prevalence of the disease, which can contribute to its management planning.

A one-year-old boy was referred to a tertiary otolaryngology clinic with bilateral postauricular swelling, hearing loss, but no tenderness or ear discharge. During the patient evaluation, a CT scan was requested to further investigate the bilateral swelling, which showed bilateral bony destructive lesions in the temporal bone area. Next, the patient was scheduled for a biopsy of this lesion under general anesthesia. A biopsy of the right mastoid confirmed the diagnosis of LCH. The patient was started on LCH IV protocol for multifocal bone lesions (MFB) with special site induction. A follow-up fluorodeoxyglucose positron emission tomography/CT (FDG PET/CT) was performed on the whole body with the impression of mild interval improvement of the temporal bones’ masses bilaterally with stable bilateral cervical lymphadenopathy.

LCH is a rare pathology that requires comprehensive effort from various medical and surgical teams to reach the right diagnoses and start the patient on the best available treatment plan.

Pediatric Langerhans cell histiocytosis of the lateral skull base

OBJECTIVE

Describe the presentation, imaging characteristics, management, and outcomes of pediatric patients with Langerhans cell histiocytosis (LCH) of the temporal bone.

METHODS

A retrospective chart review was performed between 2000 and 2014 at a single tertiary care children's hospital. Fourteen patients were identified with a diagnosis of LCH and involvement of the temporal bone.

RESULTS

Ten patients were female and ten were Caucasian. Mean age at diagnosis was 3 years (range 0.3-9.6 years). The most common presenting symptoms were scalp lesions, postauricular lesions, otalgia, and persistent ear infections. Three patients had documented hearing loss. Four cases had otic capsule invasion. Computed tomography demonstrated a lytic temporal bone lesion within the following subsites: mastoid, squamous temporal bone, external auditory canal, middle ear, and petrous apex. Four patients had intracranial disease. Extent and location of disease prompted all patients to be initially managed with chemotherapy. Surgical excision was limited to one case of localized recurrence. After a mean follow-up of 85.2 months (SD 42.4 months) there were no deaths but eight patients had a recurrence. Two patients developed long-term otologic sequelae requiring surgery. One patient developed labyrinthitis ossificans.

CONCLUSION

LCH has a varied presentation, age distribution, and treatment algorithm. This series of 14 pediatric patients with temporal bone involvement supports a limited role for surgical resection. Long-term follow-up is critical for detection of local and disseminated disease, and for monitoring of otologic complications.

A rare case of extensive cranial Langerhans cell histiocytosis, synchronously presenting as otitis externa and giant cell arteritis

Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder of unpredictable clinical course and varied modes of presentation. The spectrum of presentation is wide, ranging from isolated eosinophilic granulomas to multiple lesions and diffuse systemic involvement. We present the case of a 52-year-old man, who presented with an 8-week history of worsening otalgia and superficial temporal tenderness attributed to otitis externa within the community and subsequently giant cell arteritis. Computed tomography and magnetic resonance imaging were undertaken due to atypical features, which demonstrated bony destruction within the right greater wing of the sphenoid, squamous part of temporal and mastoid bone, with middle cranial fossa communication. Intra-orbital extension was noted with abutment of the lateral rectus muscle. Mastoid biopsies demonstrated a mixture of lymphocytes, eosinophils and monomorphic epithelial cells with pale cytoplasm and focal areas of granulation tissue/necrosis. The features were consistent with a diagnosis of LCH, and the patient was subsequently transferred to a tertiary centre for definitive treatment.

[Adult Langerhans cell histiocytosis]

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

Langerhans Cell Histiocytosis of the Temporal Bone with Otic Capsule Involvement

INTRODUCTION

This study is conducted to demonstrate that destructive lesions of the otic capsule by Langerhans cell histiocytosis (LCH) causing both radiographic and audiologic findings can be completely reversed with adequate treatment. Retrospective case review and analysis of clinical and imaging data were obtained as part of the diagnosis and treatment of patients with LCH of the temporal bone.

METHODS

With Institutional Review Board (IRB) approval, cases of LCH involving the temporal bone were searched for within the institutional databases. Criteria for inclusion was histologic diagnosis of LCH and pretreatment computed tomography (CT) demonstrating temporal bone and/or otic capsule involvement and posttreatment follow-up CT/magnetic resonance imaging (MRI) scans obtained at least 6 months after starting treatment.

RESULTS

We report eight cases of LCH of the temporal bone with three demonstrating otic capsule involvement radiographically and/or clinically. Review of posttreatment imaging revealed all three patients had complete restoration of the bony labyrinthine architecture and near or complete restoration of their hearing.

CONCLUSIONS

Though LCH of the temporal bone is a common site within the spectrum of the disease, involvement of the otic capsule remains rare. Here, we report the largest series of otic capsule involvement by LCH and investigate whether both architecture and hearing are recovered with appropriate treatment. Lastly, restoration of the bony architecture of the labyrinth suggests the mechanism of LCH is demineralization and not ablative.

Otic langerhans' cell histiocytosis in an adult: a case report and review of the literature

Objective. To present a case of otic Langerhans' cell histiocytosis in an adult. Also included the diagnosis and management of the condition and a review of the relevant literature. Case Report. We report a case of a 41-year-old man with a history of persistent unilateral ear discharge associated with an aural polyp. Radiological imaging showed bony lesions of the skull and a soft-tissue mass within the middle ear. Histological analysis of the polyp demonstrated Langerhans' cell histiocytosis. His otological symptoms were completely resolved with the systemic therapy. Conclusions. Otic Langerhans' cell histiocytosis can present in adults. Persistent ear symptoms along with evidence of soft-tissue masses within the ear and bony lesions of the skull or elsewhere should prompt the otolaryngologists to include Langerhans' cell histiocytosis in their differential diagnosis. Management should be with systemic therapy rather than local surgical treatment.

Histiocytosis of the temporal bone

Histiocytosis is a rare disease of unknown aetiology which commonly affects the head and neck region. In the ear it can closely mimic acute and chronic ear disease leading to a confusion in diagnosis. It can be easily misdiagnosed unless a high index of clinical suspicion is maintained. We present a case of Letterer Siwe disease of the temporal bone which presented with bilateral mastoid abscesses.

Multifocal langerhans' cell histiocytosis involving bilateral temporal bones, lungs, and hypothalamus in an adult

Multifocal Langerhans' cell histocytosis is a rare condition in adults. We present the case of a 31-year-old female who initially presented with a clinical appearance of acute mastoiditis. The patient ultimately had involvement of bilateral temporal bones, lungs, and hypothalamus. Treatment with methotrexate, steroids, and desmopressin acetate (DDAVP) resulted in initial clinical improvement though not resolution. The patient also underwent radiation therapy to the hypothalamic lesion. The literature is reviewed, focusing on the diagnostic challenge of this disease process in adults. The additional morbidity of surgery, specifically mastoidectomy, in the setting of Langerhan's cell histiocytosis is discussed.

Cerebrospinal fluid otorrhoea: a rare presentation of Langerhans' cell histiocytosis of the temporal bone

Objective:

To report a case of Langerhans cell histiocytosis of the temporal bone presenting with cerebrospinal fluid fistula.

Patient:

A Caucasian woman presented to a tertiary care centre in Quebec, Canada, with a new onset of cerebrospinal fluid fistula. She had a significant destructive lesion of the temporal bone, and was diagnosed with Langerhans cell histiocytosis on biopsy.

Interventions:

The patient underwent surgical resection with reconstruction of the posterior fossa and tegmen. She suffered a relapse less than one year after surgery, and was finally treated with chemotherapy.

Main outcome and results:

The patient was free of disease at three-year follow up. No recurrence of the cerebrospinal fluid leak was observed after treatment.

Conclusion:

Langerhans cell histiocytosis of the temporal bone with intra-cranial involvement is rare in adults, with only two cases previously reported. Eleven paediatric cases have been reported. To our knowledge, this patient represents the first report of cerebrospinal fluid fistula as the initial presentation of the disease.

Prognostic indicators for sensorineural hearing loss in temporal bone histiocytosis

OBJECTIVE

Our review aims: (1) to highlight the suspicion of sensorineural hearing loss (SNHL) in temporal bone Langerhans' cell histiocytosis (LCH); (2) to assess the evolution of SNHL in this pathology; (3) to identify radiologic findings of the otic capsule invasion by LCH; (4) to determine prognostic factors for SNHL in temporal bone LCH.

METHODS

We performed a literature review through MEDLINE for SNHL in temporal bone LCH related articles that were published between 1954 and 2008. We identified 12 related studies of which 18 patients were noted. We also added our case to this series. The information from the reports was analyzed to characterize the clinical and demographic data and to focus on the sensorineural hearing aspect of the disease and on the damage of the semicircular canals (SCC) and the cochlea.

RESULTS

Ten percent of patients with temporal bone LCH presented SNHL. The mean age of patients is 3.5 years among children and 35.5 years among adults. Male to female ratio is 1:1.14. There were 13 unilateral cases, 6 bilateral cases and 1 case of multisystemic histiocytosis. Cochlea and SSCs were involved in 4 and 20 temporal bones, respectively. The lateral SCC is the most frequently eroded canal. In 23 ears hearing level was reported: 15 ears had a SNHL and the remaining was a mixed or a conductive hearing loss type. 10 ears suffered from a profound hearing loss and none of them improved after treatment regardless otic capsule affected structures. In all cases of normal hearing, moderate hearing loss and severe hearing loss before treatment cochlea have not been affected. However a single or two semicircular canals invasions have been noted. Where it is reported (15 out of 25 temporal bone) there was a radiological healing of the otic capsule lesion after treatment. Remineralization occurs 6 months after treatment.

CONCLUSION

In LCH, hearing loss level before treatment can be considered as a prognostic indicator for hearing in response to treatment. Even though bone mineralization is essential for a hearing improvement, radiological healing is not a prognostic factor for better hearing level after treatment.

Cholesteatoma secondary to temporal bone involvement by Langerhans cell histiocytosis: a complication amenable to curative surgery

OBJECTIVES

To describe secondary acquired cholesteatoma in patients previously treated for Langerhans cell histiocytosis (LCH). To focus on misleading symptoms suggesting LCH relapse.

PATIENTS

This study involved 3 patients aged 12, 20, and 58 months whose conditions were diagnosed with LCH. All 3 had involvement of the mastoid and of the skin of the external ear canal (EAC) at diagnosis. They were treated with steroids and vinblastine.

INTERVENTIONS

Serial computed tomographic (CT) scans and clinical follow-up.

MAIN OUTCOME MEASURE

Exploratory surgery of the mastoid.

RESULTS

Otorrhea recurred in all 3 patients at 24, 17, and 26 months, respectively, with difficulties to clinically identify a hole in the posterior part of the EAC. The otorrhea was considered a sign of a new occurrence of LCH, leading to systemic chemotherapy in 2 cases. A CT scan showed a defect in the posterior wall of the EAC and suggested cholesteatomatous invasion of the mastoid (2 true cholesteatomas and 1 precholesteatomatous case).Surgery (canal wall up mastoidectomies) successfully removed the cholesteatoma (bilateral in 2 cases) and reconstructed the bony defect using cartilage. Biopsies ruled out LCH recurrence.

CONCLUSION

Secondary acquired cholesteatoma (through a bony defect of the EAC) may occur in patients previously treated for LCH. Recurrence of symptoms and bone destruction on CT may wrongly suggest LCH recurrence. Surgery allows removal of the cholesteatoma as well as EAC reconstruction and control biopsy.

Langerhans' cell histiocytosis of the temporal bone: successful treatment of sensorineural hearing loss with low-dose radiotherapy

Objective:

To present the successful treatment of sensorineural hearing loss secondary to Langerhans' cell histiocytosis with low-dose radiotherapy, and also the disparity between radiological resolution of Langerhans' cell histiocytosis lesions and lack of sensorineural hearing loss improvement, accompanied by a review of the literature on otolaryngological manifestations and management of Langerhans' cell histiocytosis.

Case report:

Langerhans' cell histiocytosis is a multisystem disease which frequently causes osseous lesions in the temporal bones. Hearing loss is usually conductive but may be sensorineural with lesions of the petrous temporal bone. We present a case of sensorineural hearing loss secondary to Langerhans' cell histiocytosis affecting the labyrinth and internal auditory meatus, which resolved following radiotherapy. Contralateral sensorineural hearing loss in the same patient, previously treated with chemotherapy, did not resolve despite radiological resolution of the temporal bone lesions.

Conclusion:

We suggest that timely radiotherapy for treatment of sensorineural hearing loss secondary to Langerhans' cell histiocytosis is an appropriate treatment option.

Langerhans' cell histiocytosis of the temporal bone in children

OBJECTIVE

Langerhans' cell histiocytosis (LCH) is a rare pathology that implies an abnormal proliferation of these kinds of cells associated with a granular infiltration that affects different structures of the human body, including the temporal bone. The authors present their series of LCH of the temporal bone in children at the Sainte-Justine university hospital. The twofold objective of this study is to illustrate the clinical presentation, management and prognosis of this disease, and to compare these results with previously reported series.

METHODS

A retrospective study was conducted between 1984 and 2007 with patients diagnosed and treated for a LCH of the temporal bone at the Sainte-Justine university hospital, a paediatric tertiary care center. A chart review was performed to obtain demographic, clinical, paraclinical, and therapeutic data. They were analysed and compared to other published series. Through a MEDLINE query, we found that since 1966, 50 articles dealing with a LCH of the temporal bone have been published.

RESULTS

Fifty-nine cases of LCH were diagnosed and among them, 10 children had temporal bone involvement. They were four females and six males with a mean age of 3.28 years. The two most frequent clinical manifestations were the presence of a mass in the temporal region (70%) and otitis (60%). Two of our patients had a unifocal lesion of the temporal bone implicated. Eight patients had a multisystem involvement among which, two showed evidence of organ dysfunction. In 80% of cases, the diagnosis was made by immunohistochemical findings of the S-100 protein and/or the CD1 antigen. The common radiological finding on a skull CT scan is a lytic lesion in the temporal bone. Seven patients were treated by chemotherapy, two were treated by radiotherapy as a primary treatment, and one received radiotherapy for a recurrence on the pituitary gland. Finally, one patient was treated with local steroid injections. Two patients had a recurrence. All our patients were in total remission on a mean average of 1.6 years after the diagnosis. Our results concord with other studies in which the prognosis of unifocal bone disease is excellent and children with a multifocal disease have a survival rate of 65-100%.

CONCLUSION

LCH is a rare disease. A high-index suspicion should be raised in the context of a temporal mass, chronic otitis, and otorrhea. A biopsy is recommended in the presence of a temporal bone lytic lesion. Chemotherapy is the preferred therapeutic modality.

Mondini dysplasia and recurrent bacterial meningitis in a girl with relapsing Langerhans cell histiocytosis

We report a case of a girl with Langerhans cell histiocytosis (LCH) of multifocal bone disease, who developed recurrent bacterial meningitis and unilateral sensorineural hearing loss during the relapsing course of the disease. Mondini dysplasia, a congenital inner ear anomaly, was suspected by high resolution computed tomographic scan and the dysplasia with cerebrospinal fluid leakage was confirmed by surgery in the ipsilateral ear showing hearing loss. Although rare, congenital inner ear anomalies such as Mondini dysplasia should be kept in mind in pediatric patients with hearing impairment and/or recurrent bacterial meningitis during chemotherapy for various types of neoplasms including LCH.

Adult onset Langerhans cell histiocytosis of the orbit--a case report

PURPOSE

To report an interesting case of adult onset Langerhans cell histiocytosis in a 41-year-old male with clinicopathological correlation.

DESIGN

Interventional case report.

MATERIALS AND METHODS

A 41-year-old male presented with an ill-defined mass occupying the temporal quadrant of the left orbit. Computerized tomography revealed an ill-defined extraconal mass involving the superolateral aspect of the left orbit with areas of osteolysis involving the lateral and superior orbital walls. The mass excised at orbitotomy showed microscopic features consistent with Langerhans cell histiocytosis. Immunohistochemistry with CD-68 macrophage marker and S-100 was positive, confirming the diagnosis. Treatment included oral steroids and radiotherapy. At 6 months follow-up, he developed a punched-out lytic lesion in the left parietal calvarium. He again received external beam radiotherapy. At 14 months follow-up, he is doing well with no recurrences.

CONCLUSIONS

Adult onset Langerhans cell histiocytosis, though rare, should be included in the differential diagnosis of lytic lesions of the lateral orbital wall in an adult patient.

Langerhans’ Cell Histiocytosis: Current Trends and the Role of the Head and Neck Surgeon

Langerhans’ cell histiocytosis (LCH)—once called histiocytosis X— is a complex reticuloendothelial disease that often involves the head and neck. We discuss the current nomenclature of this disease and review its pathologic and clinical characteristics, with particular emphasis on the role of the head and neck surgeon. LCH can be challenging to diagnose, and the otolaryngologist must be familiar with its varied presentations. Because LCH usually responds well to medical therapy and extensive resection can easily cause more morbidity than the disease itself, a minimalist approach to treatment usually provides the best outcome. We also discuss the case of a 9-month-old girl with LCH who presented with aggressive head and neck disease.

Langerhans' Cell Histiocytosis of the Labyrinth in Adults

OBJECTIVE

To describe and analyze three unusual cases of Langerhans' cell histiocytosis of the temporal bone in adults.

STUDY DESIGN

Retrospective case review.

SETTING

A tertiary referral center.

PATIENTS

Three adult patients with progressive sensorineural or mixed hearing loss, vertigo, and tinnitus as presenting symptoms of Langerhans' cell histiocytosis of the temporal bone.

INTERVENTION

Patients were evaluated by means of computed tomography and magnetic resonance imaging. All patients underwent complete surgical excision of the lesion via a transmastoid approach, extended to a translabyrinthine approach in one case. One patient with a multifocal disease underwent excision of a mandibular lesion 1 year later, followed-up by chemotherapy.

RESULTS

The Langerhans' cell histiocytosis was located adjacent to or within the area of the endolymphatic sac region in all cases. The middle ear was spared. Hearing function was preserved in the two patients who had serviceable hearing preoperatively. No complication occurred.

CONCLUSION

Langerhans' cell histiocytosis of the temporal bone is centered on or adjacent to the endolymphatic sac. The fact that the endolymphatic sac plays an immunologic role in the inner ear suggests that the infiltration of the Langerhans' cell may derive from it.

Langerhans' cell histiocytosis with bilateral temporal bone involvement

BACKGROUND

Langerhans' cell histiocytosis (LCH) is a rare disease with variable clinical appearance. The etiology of LCH remains unclear to date. It is currently believed that clonal accumulation and proliferation of CD1a-positive Langerhans' cells are causative.

METHODS

A 2-year-old boy presented with hypacusis and disturbance of balance. Auditory brainstem-evoked responses (ABRs) revealed severe bilateral labyrinthine hearing loss. Magnetic resonance imaging (MRI) showed inflammatory changes with bone erosion in both temporal bones including labyrinthine systems and mastoid processes.

RESULTS

During bilateral surgical exploration, fragile slightly yellowish tissue with necrotic areas was found that turned out to be LCH on histology. Chemotherapy with vinblastine and prednisone was subsequently initiated, leading to continuing complete remission.

CONCLUSIONS

The initial presentation of LCH with bilateral temporal bone involvement is a very rare condition. The signs and symptoms of otologic histiocytosis can mimic those of acute and chronic infectious ear disease. Only a surgically obtained biopsy leads to definitive diagnosis and appropriate therapy.

Langerhans' cell histiocytosis: report of a case with temporal localization

The authors report a case of Langerhans' cell histiocytosis (LCH) with temporal localization and rapidly evolving initial clinical presentation in a 12-year-old boy. This disease of currently unknown etiology is actually considered a proliferative entity of cells with phenotypic characteristics of normal Langerhans' cells. An immunoregulation defect leading to abnormal maturation and migration of Langerhans' cells might be the basis for LCH. According to the Hystiocyte Society diagnostic criteria, ATPase, S 100 and D-mannoxidase positivity in addition to typical hystopathologic findings are sufficient for diagnosis of LCH. Head and neck localization of LCH occurs in about 70% of cases; males are more frequently affected than females, age at presentation varies from a few months to 15 years. Presenting features, initial diagnostic evaluation, differential diagnosis and treatment protocol of a unifocal monosystemic temporal bone localization of LCH are presented.

Langerhans histiocytosis of temporal bone: role of magnetic resonance imaging

Langerhans cell histiocytosis (LCH) may involve nearly every organ of the body. In children, head and neck involvement has been reported in as many as 82% of patients. Sites of head and neck involvement include skull, temporal bone, orbit, mandible, maxilla and cervical nodes. In addition, patients may have coexisting central nervous system (CNS) involvement adjacent to, or remote from, osseous lesions. Magnetic resonance imaging (MRI) of the temporal bone in patients with LCH is ideal for evaluating the extracranial extent of the soft-tissue mass and is complementary to computed tomography (CT) in the assessment of osseous erosion. MRI is superb in the evaluation of intracranial extension, usually into the middle cranial fossa, and of patency of adjacent vascular structures. It is the imaging modality of choice to evaluate patients with suspected CNS involvement of LCH, which includes lesions of the infundibulum, cerebrum, cerebellum, and extra-axial spaces.

Ear involvement in childhood Langerhans' cell histiocytosis

BACKGROUND

Ear involvement (EI) in Langerhans' cell histiocytosis (LCH) occurs quite often. We reviewed the Italian pediatric population of 251 children with LCH diagnosed between 1982 and 1995, focusing on EI, to highlight the prevalence, the clinical presentation, the outcome during follow-up, and the prognostic impact of otologic LCH.

METHODS

EI was defined by chronic otorrhea and/or mastoid infiltration, external auditory meatus lesions, and middle/internal EI. The age at diagnosis, sex, system involved, organ dysfunction, treatment, disease control, and outcome were recorded.

RESULTS

EI was noted at presentation in 34 children (13. 5%). They had a younger age at diagnosis (p=.0013) and near totality of multisystem disease (93.8% of patients with EI). Among patients with multisystem disease, children with EI seemed to have a higher risk of poor response and a higher percentage of second line treatment (p=.003).

CONCLUSIONS

EI seems to identify patients with a particular disease behavior, which requires a more accurate evaluation at diagnosis, staging and treatment, and a strict follow-up, considering the possibility of an unfavorable outcome.

Labyrinthine involvement in Langerhans' cell histiocytosis

BACKGROUND

Langerhans' cell histiocytosis, a rare condition caused by the proliferation of abnormal Langerhans' cells ('LCH cells') and an accompanying granulomatous infiltrate, can affect several organs including the ear. External and middle ear involvement are common with a reported incidence as high as 61%. The bony labyrinth is resistant to erosion by the granulation tissue, thereby protecting the cochlea and vestibular structures. Probably for this reason, involvement of the inner ear is rare, with few case reports in the literature.

PATIENTS

We report two girls, one with bilateral and the other with unilateral mastoid involvement, in whom there was invasion of the labyrinth. The first girl had 'single system' LCH affecting only bone and developed an acute hearing loss due to invasion of the cochlea, while the second had both bone and skin involvement and labyrinthine involvement was diagnosed on imaging prior to the onset of labyrinthine symptoms.

CONCLUSION

Inner ear involvement can lead to permanent deafness, which may be prevented by early institution of treatment. Threatened inner ear involvement requires urgent systemic medical therapy with steroids, possibly combined with chemotherapy.

Eosinophilic granuloma of the clivus: case report, follow-up of two previously reported cases, and review of the literature on cranial base eosinophilic granuloma

OBJECTIVE AND IMPORTANCE

To our knowledge, this is the first reported case of the use of stereotactic radiotherapy for an eosinophilic granuloma (EG) of the clivus. We report follow-up information on two previously reported cases and suggest a management plan for this rare lesion.

CLINICAL PRESENTATION

We report the case of a 4.5-year-old boy who presented with a complete abducens palsy on the right with an associated head turn. A computed tomographic scan of his head revealed a lytic lesion on that side, and magnetic resonance imaging showed the mass to be of low intensity on T1-weighted images and of high intensity on T2-weighted images with heterogeneous enhancement.

INTERVENTION

A transnasal stereotactic biopsy was performed, revealing an EG. The patient was treated with stereotactic radiotherapy, and he became symptom-free with radiographic resolution of his lesion. Reviewing the literature, we found 13 series with 87 cases of EG in the petrous portion of the temporal bone. EG in the cranial base occurring outside of the temporal bone or in the temporal bone and extending intracranially is, however, quite rare, with only nine other cases reported, two of them clival.

CONCLUSION

These findings suggest a classification schema in which cranial base EG lesions be grouped with either the more common extracranial petrous temporal bone lesions or the very rare intracranial lesions. Although there are few cases in the literature, treatment results indicate that clival EG, and perhaps all intracranial cranial base EGs, be treated by a biopsy alone, followed by surgery or stereotactic radiotherapy if there is an incomplete resolution of the symptoms or if there is a recurrence.

Head and neck Langerhans cell histiocytosis

Among the potential sites of involvement by Langerhans cell histiocytosis (LCH), the head and neck region is the most commonly cited. Though principally a pediatric disease, LCH can affect any age group. It can be unifocal (skeletal) or multifocal (skeletal and/or visceral); it appears as though the presence of visceral lesions is more common in the youngest patients, and may be associated in some with a rapidly progressive course resulting in death. Head and neck manifestations may mimic such varied entities as eczema, otitis media, osteomyelitis, and cholesteatoma. Current approaches to therapy are less aggressive than they were in the past, and are particularly intended to monitor for and treat any complicating secondary infections (which may develop in the youngest patients with multifocal disease including visceral involvement). The prognosis is very good for unifocal skeletal system disease, and poor for multifocal disease with involvement of tissues other than bone.

Eosinophilic granuloma of the head and neck: CT and MRI features in three cases

We report the radiological findings and more specifically the MRI features in three typical cases of Langerhans' cell histiocytosis of the head and neck. All three cases were of solitary eosinophilic granuloma of bone: two mandibular and one temporal bone lesion. Reports on the MRI features of head and neck eosinophilic granulomas are rare.