Eosinophilic granuloma: resolution of maxillofacial bony lesions following minimal intervention. Report of three cases and a review of the literature

Langerhans cell histiocytosis in adults: literature review

Langerhans cells histiocytosis is a variant of malignant histiocytosis. The course and symptoms vary. patients with localized forms have a better prognosis, because local therapy is effective. patients with multifocal forms of histiocytosis receive systemic drug therapy, which cures some of the patients. This review provides up-to-date data about typical presentation of the organ involvement, diagnosis, course and therapy of various forms of Langerhans cells histiocytosis.

Spontaneous regression of an orbital Langerhans cell histiocytosis after biopsy: A case report. Spontaneous regression of an orbital Langerhans cell histiocytosis

Langerhans histiocytosis or Langerhans cell histiocytosis (LCH) is a rare benign pathology representing less than 1% of orbital tumors. It can cause either localized or generalized lesions, leading to the destruction of hard and soft tissues. Eosinophilic granuloma is the most benign form and the predominant clinical presentation of LCH. We report a case of eosinophilic granuloma with orbital involvement in an 18-year-old male patient. Orbital radiotherapy was initially planned, but finally it was not performed due to a spontaneous regression of the lesion after the incisional biopsy. The presented case supports an expectant attitude given the possibility of a spontaneous regression after the biopsy, especially in small lesions. However, long-term follow-up is essential given the risk of recurrence.

A case of langerhans cell histiocytosis of the mandible that spontaneously regressed after biopsy in a child

In younger patients of LCH, we should consider that the effectiveness of follow-up without aggressive treatment for SS-type LCH in the oral and maxillofacial bone. However, there are very rare case in which an SS-type LCH recurred after showing a healing tendency. Regular follow-up must be performed even after healing.

Unisystem Langerhans cell histiocytosis in maxillofacial region in pediatrics: comprehensive and systematic review

BACKGROUND

The study aimed to identify, enlist, and analyze cases of unisystem LCH in the maxillofacial pediatric population to understand the clinical presentation and encourage the consideration of this rare disease in the differential diagnosis. Langerhans cell histiocytosis (LCH) is an aggressive benign condition affecting mainly the pediatric population. It can be easily masked as periodontal disease in the maxillofacial region. Early diagnosis and a systemic evaluation are of utmost importance.

METHODOLOGY

We are presenting a complete review of literature in the pediatric population according to PRISMA guidelines for clinicopathologic, histopathological, immunohistochemistry, and treatment for unisystem LCH. The risk of bias assessment across studies was done using a Case series appraisal checklist by Guo et al. 53 RESULTS: Forty-nine articles (152 cases) were selected which met our inclusion and exclusion criteria to be included in our review. Most of the patients fall in 6-12 years of age with the involvement of the mandibular body region in 40.79% cases. This disease mainly presents as erythematous gingiva, pain, swelling, and mobile teeth. Management can range from minimal intervention to chemotherapy and surgery.

CONCLUSION AND PRACTICAL IMPLICATIONS

Although this is a rare condition, it should be considered especially in the pediatric population with periodontitis type lesions and floating teeth and comprehensive management should be followed. Early diagnosis of the disease is very important.

Desmoid-type fibromatosis of the lower extremity: A unique case of complete lesion resolution following core needle biopsy

Desmoid-type fibromatosis (DF) is a rare neoplasm characterized by fibroblastic and myofibroblastic proliferation. While characterized as a benign lesion that does not metastasize, desmoid-type fibromatosis exhibits a wide range of behavior from aggressive local tissue invasion and post-surgical recurrence to spontaneous regression. Tumor regression can occur following systemic medical therapy or rarely may occur in the absence of therapy. We present a case of a 50-year-old female with a left thigh vastus medialis intramuscular mass which underwent imaging work-up and subsequent core needle ultrasound-guided biopsy showing results of desmoid-type fibromatosis. Following biopsy, the tumor showed prompt, complete regression with complete MRI resolution 2 months following biopsy. The patient showed no evidence of disease recurrence out to one year on MRI surveillance. This case report will discuss desmoid-type fibromatosis imaging features, treatment strategies, spectrum of disease behavior, and atypical behavior such as the spontaneous tumor regression as seen in this case report. To our knowledge there have been no reported cases of DF spontaneous regression 2 months following a core needle biopsy. Understanding the variable behavior of desmoid-type fibromatosis can assist the radiologist in guiding management of these lesions with the goal of optimizing clinical outcomes and preventing unnecessary aggressive treatments for stable or regressing disease.

Outcome of Surgery as Sole Treatment of Eosinophilic Granuloma of Jaws

Langerhans cell histiocytosis (LCH) is characterized by the congregation of proliferating langerhans cells (LC). Langerhans cells are a part of dendritic cell system of primary immune response that is responsible for presenting antigen to lymphocytes. Being a rare disease, the total incidence of LCH is reported to be 1 in 2 million people. LCH mainly affects children and young adults, with a slight male predilection. LCH is clinically divided into three groups namely Letter-Siwe disease (multiple multi organ affecting LCH at very young age), Hand-Schuler-Christian disease (LCH of bone involvement exophthalmos and diabetes insipidus), and Eosinophilic granuloma (LCH of bone, solitary or multiple). The extent of involvement influences the treatment planning. In this retrospective study, we survey five patients with eosinophilic granuloma in jaws (bony LCH). The diagnosis was confirmed by tissue biopsy and histopathologic examination. Surgery and curettage of the lesions were carried out under general or local anesthesia. After surgery, the patients were examined clinically every 6 month in the first year and then once in a year. The overall outcome was excellent. According to the results, it can be concluded that surgical curettage of localized eosinophilic granuloma is an appropriate and sufficient treatment.

Langerhans cell histiocytosis of the jaw, a mimicker of osteomyelitis on CT and MR images: A retrospective analysis

Differential diagnosis of Langerhans Cell Histiocytosis (LCH) in the jaw is essential for early treatment including systemic therapy. Records of 17 patients (6 men and 11 women; mean age, 14 years) with histologically confirmed LCH were reviewed. All the lesions occurred in the mandible. Most of the cases (n=12) were intraosseous type LCH, only 5 patients had alveolar type LCH. Patients complained of facial swelling and pain most likely. In the 14 patients who underwent CT and/or MR imaging, all LCH lesions were osteolytic, with a mean size of 23 mm. LCH presented as expansile lesions with periosteal new bone formation, perilesional sclerosis, fluid attenuation/signal within the lesion, and inflammatory changes in adjacent soft tissues on CT/MR images. Considering the major symptoms of LCH were swelling and pain, the differential diagnosis of LCH from osteomyelitis might be more difficult. The differential diagnosis for osteolytic lesions of the jaw with surrounding inflammatory changes should include LCH, especially in young patients.

Intralesional Triamcinolone for Treating Mandibular Langerhans Cell Histiocytosis: A Case Report and Literature Review

Langerhans cell histiocytosis is a rare condition ranging in manifestation from a focal boney lesion to multisystem involvement. Several treatment modalities have been proposed including curettage, low-dose radiotherapy, chemotherapy and intralesional injection of corticosteroids. These treatment options can be used as a single or combined approach. Prognosis depends on the extent of systemic involvement, and solitary lesions respond favorable to treatment. Here, the authors report a case of a 10-year-old male patient with Langerhans cell histiocytosis affecting his right posterior mandible that was successfully treated with intralesional injection of triamcinolone in multiple sessions. Complete recovery was confirmed clinically and radiographically in 18 months from the time of diagnosis.

Multidisciplinary rehabilitation of eosinophilic granuloma with bone graft surgery and a modified implant-supported hybrid prosthesis: A case report with a 6-year follow-up

Eosinophilic granuloma is the most common form of Langerhans cell histiocytosis and corresponds with bone lesions characterized by pain, rapid growth, and high tendency of recurrence after inadequate curettage. It is a rare disease that is difficult to diagnose clinically and radiographically because it mimics other odontogenic cysts and tumors. In this report, the reconstruction of an osseous defect with an iliac graft and a modified implant-supported hybrid prosthesis after surgical excision of an eosinophilic granuloma in the mandible of a 27-year-old male patient was described. The patient was satisfied with the functional and esthetic results of the implant-supported restoration and a 6-year follow-up showed no sign of recurrence.

Reconstruction of a severe mandibular pathological fracture caused by Langerhans cell histiocytosis using a free fibula osteocutaneous flap:a case report

Langerhans cell histiocytosis (LCH) is a rare disease in which Langerhans cells, which are bone marrow-derived antigen-presenting cells, proliferate in single or multiple organs. We successfully treated a patient with unifocal LCH of the mandible with malocclusion due to a severe pathological fracture, using reconstruction with a vascularised free bone.

Spontaneous remission of eosinophilic granuloma of the maxilla after incisional biopsy: a case report

Background

Langerhans cell histiocytosis (LCH), previously known as Histiocytosis X, is an infrequent disease that congregates a wide spectrum of clinical presentations with variable systemic involvement. Unification of these diseases under only one category is based on the almost identical histopathologic features of the lesions, but the etiology and proper approach for each presentation remains controversial. The localized alternative of Langerhans cell histiocytosis (LLCH), known as Eosinophilic Granuloma (EG) of bone, is the predominant clinical presentation of LCH. The maxilla is involved in 1 % of the head and neck region cases, representing an uncommon condition in this area.

Case Presentation

In this clinical case report, it is described a case of a 16-year-old male patient with an asymptomatic osteolytic lesion at first upper left molar apical level, a finding detected on control radiographic images was reported as “Monostotic Eosinophilic granuloma of the maxillary bone”, which was later confirmed through an incisional biopsy. A surgical excision was initially planned, but finally it was not performed due to a spontaneous healing of the lesion after the incisional biopsy.

Conclusions

The presented case supports a conservative approach in the management of solitary EG of maxillary and mandibular bone lesions and even supports an expectant attitude in the course of treatment given the possibility of a spontaneous regression after the biopsy, especially in small lesions.

Eosinophilic Granuloma of the Mandible: Is a Conservative Treatment Sufficient for Local Disease Control?

Eosinophilic granuloma is the most benign and common form of the Langerhans cell histiocytosis, a rare proliferative disease that can affect single or multiple organs. In the quite common head and neck manifestation these lesions can be confused in the beginning, with other bone diseases such as odontogenic cysts, periodontal disease, or malignancies. Treatment varies depending on the size, number, localization of the lesions, and patient's general conditions. The authors describe here a patient of a single lesion of eosinophilic granuloma localized in the posterior mandible region treated with a very conservative surgical approach in a patient with poor socio-economic conditions. The authors performed teeth extractions, an excisional biopsy and open curettage and after a follow-up of 24 months without partial mandible resection and reconstruction time the lesion had healed. The clinical situation confirmed that, in carefully selective patients, a conservative approach could be a useful therapeutic opportunity.

Spontaneous resolution of an eosinophilic granuloma of the mandible following open biopsy

Langerhans cell histiocytosis X is a clonal proliferation of dendritic cells of the immune system, which can affect multiple organ systems and range in behavior from a benign inflammatory process to a much more aggressive process. Only few isolated cases have been reported in the jaws. This case represents an example of Langerhans cell histiocytosis X in the mandible, which resolved following incisional biopsy without any further surgical intervention.

Isolated Langerhans Cell Histiocytosis Bone Lesion in Pediatric Patients: Systematic Review and Treatment Algorithm

OBJECTIVE

The present study reviewed all cases reported of isolated Langerhans cell histiocytosis bone lesions in the head and neck of pediatric patients. The objective was to create a treatment algorithm to facilitate the diagnosis and management of these lesions.

DATA SOURCES

Eligible articles were identified through a comprehensive search of the following electronic databases: PubMed, Ovid Medline, Embase, and Cochrane Library.

REVIEW METHODS

Two authors independently reviewed the titles and abstracts retrieved by the electronic search concordant with the criteria for study eligibility. The lists of articles from each author were jointly reviewed and a common list created. All relevant articles were reviewed in hard copies and as full texts to justify inclusion.

RESULTS

A total of 201 patients (67% male, mean age: 8.1 ± 4.3 years) were included from 45 studies. Clinical presentations included swelling (64%), pain (9%), or both (18%). The skull (61%) and the orbit (24%) were the most common location for isolated bone lesions in the head and neck. The most frequently documented management option was resection, followed by observation, chemotherapy, and intralesional steroid injection.

CONCLUSIONS

Due to its rarity and variability in presentation and severity, treatment of these lesions has yet to be standardized. Based on the review, a diagnosis and treatment algorithm was created for head and neck surgeons when encountering these types of lesions.

Treatment of mouth and jaw diseases with intralesional steroid injection

Many lesions of the oral region are treated with surgical methods such as curettage and resection. Chemotherapy and radiation therapy with or without surgical intervention can be used as an adjunct in some cases. Intralesional steroid injection is a conservative procedure which is already used in various regions of the body and joints. This technique is used also for a number of mouth and jaw lesions. Localized langerhans cell histiocytosis, central giant cell granuloma, oral submucous fibrosis, oral lichen planus, lichen sclerosus of the oral mucosa, lymphatic malformations and orofacial granulomatosis can be considered among these diseases. The purpose of this review is to investigate the effects of intralesional steroid injections in the treatment of oral diseases.

A rare occurrence of Langerhans cell histiocytosis in an adult

Langerhans Cell Histiocytosis (LCH) is a disease process characterized by accumulation and infiltration of cells, showing ultrastructural and immunohistochemical similarities to Langerhans’ cell, in the affected tissues. It exhibits extreme clinical heterogeneity. LCH was historically divided into 3 clinical entities based on extent of tissue involvement and severity of presentation. These 3 entities were eosinophilic granuloma, Hand-Schuler-Christian disease, Letterer-Siwe disease. Owing to similarities of their histologic appearance, they were grouped together under the term histiocytosis X. It was recently changed to LCH, emphasizing the primary cell involved in the disease process. LCH is a rare disease with an incidenceestimated to be 4.0 to 5.4 per million population. Males are affected twice as frequently as females. The disease may occur at any age with peak incidence in children aged 1 to 3 years. We describe an unusual case of a 65-year-old man who presented with painless swelling in anterior region of mandible.

Successful treatment of pediatric histiocytic sarcoma using abbreviated high-risk leukemia chemotherapy

Histiocytic sarcoma (HS) is a malignant tumor composed of proliferating cells of histiocytic origin. True HS is exceedingly rare, particularly in pediatric patients. These tumors are frequently aggressive, and outcome for patients with HS has traditionally been poor. There is currently no consensus on the optimal management of these tumors, with the literature consisting largely of case reports and small case series utilizing a wide variety of therapies. We describe a case of HS in an 8-year-old female who was successfully treated with an abbreviated leukemia chemotherapy regimen.

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

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

Canine Oral Eosinophilic Granuloma Treated with Electrochemotherapy

A case of a canine oral eosinophilic granuloma in a 14-year-old female crossbred is described. The dog was presented with a history of ptyalism, halitosis, local pain, decreased appetite, and blood staining noted on food and water bowls. Clinical, hematologic, and biochemical examinations, abdominal ultrasonography, and 3-view chest radiographs were performed, and no metastases were found. Histopathologic examination of two 6 mm punch biopsies from the oral lesion revealed the presence of eosinophilic granulomatous lesions in the submucosa. After treatment with corticosteroids and wide spectrum antibiotics no significant changes in clinical signs and lesion size were observed. Electrochemotherapy (ECT), a novel tumor treatment routinely used for cutaneous and subcutaneous tumors in human patients in the European Union since 2006, was used to treat the eosinophilic granuloma. The procedure was performed under general anesthesia, followed by intravenous administration of bleomycin. Six weeks after treatment a complete response with disappearance of the mass and improvement of clinical signs were observed.

Eosinophilic granuloma in the anterior mandible mimicking radicular cyst

Eosinophilic granuloma is a common expression of Langerhans cell histiocytosis and corresponds with typical bone lesions. The radiographic appearance of eosinophilic granuloma in the jaw is variable and not specific. It may resemble periodontitis, radicular cyst, or malignancies. The purpose of this report is to describe the characteristic radiographic features of eosinophilic granuloma of a 39-year-old male. The lesion in the anterior mandible was first diagnosed as radicular cyst because the radiographic findings were ovoid radiolucent lesion with well-defined border. However, careful interpretation revealed a non-corticated border and floating tooth appearance that were the characteristic radiographic features for the differential diagnosis. Early clinical signs of eosinophilic granuloma can occur in the jaw and a bony destructive lesion might be mistaken for periodontitis or an odontogenic cystic lesion; therefore, careful interpretation of radiographs should be emphasized.

Langerhans cell histiocytosis of the parietal bone with epidural and extracranial expansion - case report and a review of the literature

Langerhans cell histiocytosis is a rare neoplasm that belongs to the histiocytic and dendritic cell neoplasm group according to the 2008 WHO classification. It has been defined as neoplastic proliferation of Langerhans cells that express CD1a and S-100 proteins and have Birbeck granules on the ultrastructural examination. Clinical presentation and behaviour are heterogeneous and can range from a solitary lytic bone lesion with a favourable course to a fatal disseminated leukaemia-like form, with a wide spectrum of intermediate clinical presentations between these two extremes. Here, we present a case report of a solitary calvarial lesion in an adolescent boy along with a review of the literature. Presenting features, initial diagnostic evaluation and treatment protocol of a unifocal monosystemic calvarial location of LCH are presented.

Treatment of localized Langerhans' cell histiocytosis of the mandible with intralesional steroid injection: report of a case

Localized Langerhans cell histiocytosis (LLCH), formerly known as eosinophilic granuloma, mainly affects the skull, mandible, vertebrae, and ribs in children and the long bones of adults. Symptoms range from none to pain, swelling, and tenderness over the site of the lesion. General malaise and fever occasionally are present. Radiographically, lesions appear as radiolucent areas with well demarcated borders. LLCH may resolve spontaneously after biopsy in a period of months to years. However, if features include continuous pain, decrease of function, pathologic fractures, migration and resorption of teeth, or rapid progression, then active treatment needs to be considered. Treatment approaches include surgery, radiotherapy, chemotherapy, and intralesional injection of corticosteroids. In children with mandibular LLCH, 1 dose of methyprednisolone succinate injection has proven to be adequate. However, injections have not been performed in cases involving pathologic fracture. We report a new case of LLCH of the mandible that caused a pathologic fracture in an adult patient. Repeated intralesional corticosteroid injections resulted in fracture line disappearance within 14 months and lesion healing by the end of the 36-month follow-up.

Intralesional corticosteroid therapy for mandibular Langerhans cell histiocytosis preserving the intralesional tooth germ

BACKGROUND

Langerhans cell histiocytosis (LCH, histiocytosis X, ICD-O 9751/1) refers to a neoplastic proliferation of Langerhans cells. The course of the disease determines the treatment and prognosis. Solitary forms (eosinophilic granuloma) and limited multilocational lesions may be treated successfully with local surgical intervention and intralesional corticosteroid injection.

PURPOSE

Presentation of our own case will review LCH, a very rare disease entity in oral-facial surgery and will document that intralesional corticosteroid injection is a less invasive alternative to the classical surgical curettage and local radiation therapy.

CASE REPORT

In a 10-year-old boy, a progressive, pressure-sensitive swelling had developed within 1 week in the left paramandibular and submandibular area. Dental status was good. Diagnostic imaging demonstrated a diffusely contoured osteolysis caudal to tooth germ 37 with infiltration of the adjacent chewing muscles. Histological evaluation of the intraoral biopsy sample established an LCH. Having excluded a multifocal form of LCH, treatment with intralesional injection of methylprednisolone 200 mg was chosen. Symptoms of pain were quickly relieved and the swelling receded. Follow-up visits 6 weeks, 3 months, and 6 months after corticosteroid injection revealed continuous regression of mandibular osteolysis. OPG and MRI after 17 months demonstrated a good osseous consolidation in the left mandibular angle area, but a still discernible bone marrow edema. Development of the intralesional tooth germ 37 appeared normal.

CONCLUSION

Local surgical interventions continue to be central to the range of accepted therapeutic measures. However, the increasing numbers of reports on the successful treatment of solitary LCH by intralesional corticosteroid injection suggest that this treatment option should be considered especially in children to preserve tooth germs.

[Mandibular Langerhans cell histiocytosis]

INTRODUCTION

Langerhan's cell histiocytosis is defined as an abnormal proliferation of Langerhans cells in various organs and tissues (bone, skin, lymph nodes...). Among facial locations, mandibular involvement is the most frequent and occurs in young people less than 20 years. The aim of this report is to review the characteristic features of this disease, the current means of diagnosis and treatment through two case reports.

CASES

Two male patients aged 10 and 55 years respectively presented with single mandibular location of Langerhans cell histiocytosis. The diagnosis was confirmed by histological examination of the biopsy specimen. The first patient underwent surgical resection of the tumor. No recurrence was observed. In the second patient, the postoperative course was marked by the appearance of an inflammatory phenomenon in the adjacent skin and mucosa, successfully treated by intralesional corticosteroid therapy.

DISCUSSION

Langerhan's cell histiocytosis is a rare disease. The mandibular location has variable clinical expressions which can vary from dental mobility to tumor development in the gingiva. The radiological appearance is also variable; histological proof is required for diagnosis. Treatment depends on the number and locations of the lesions. In case of a single location, the treatment options may vary from a "wait and see" attitude to a non aggressive surgery, with a possible local corticosteroid therapy or radiothe-rapy. For multiples locations, chemotherapy is indicated.

Eosinophilic granuloma of the jaws: an analysis of clinical and radiographic presentation

Eosinophilic granuloma (EG) is the localized and mildest form of histiocytosis-X group of diseases. In this study, 22 patients of pathologically proven EG involving the jaws were retrospectively studied concerning the clinical and radiographic presentation. The clinical and radiographic presentation of the 22 cases was quite varied, and the accuracy of clinical and radiographic diagnosis was low. However, the clinical and radiographic presentation correlated with the lesion site, and accordingly all the jaw lesions could be divided into three types (Alveolar Type, Intraosseous Type, and Mixed Type). Our classification based on the lesion sites reveals the correlation between the clinical and radiographic presentation of EG and the lesion sites, and may be useful in the identification of lesions of EG in the jaws.

Langerhans cell histiocytosis: current insights in a molecular age with emphasis on clinical oral and maxillofacial pathology practice

Langerhans cell histiocytosis (LCH) commonly involves the oral and maxillofacial region, and comes to the attention of dental practitioners when a patient presents with orofacial pain and a bony or soft tissue lesion. This is a relatively rare entity, which has made it difficult to investigate the clinical, biologic, and molecular aspects of the disease. Treatment protocols are not well defined, particularly in adults. During the past decade, the Histiocyte Society has formulated various LCH categories, based on risk stratification, and treatment protocols for the pediatric population. Adult trials are currently available through the Histiocyte Society. Although there has been considerable controversy, the neoplastic nature of LCH has been established by demonstrating clonality. LCH symptoms and the development and persistence of LCH lesions have been ascribed to a "chemokine/cytokine storm" due to autocrine and paracrine mechanisms. Discovery of biologic, cytogenetic, and molecular abnormalities in LCH have already affected treatment by providing novel therapeutic targets.

Langerhans' cell histiocytosis: pathology, imaging and treatment of skeletal involvement

Langerhans' cell histiocytosis (LCH) is manifested in a variety of ways, the most common being the eosinophilic granuloma, a localized, often solitary bone lesion that occurs predominantly in the pediatric age group. The hallmark of LCH is the proliferation and accumulation of a specific histiocyte: the Langerhans' cell. In bone this may cause pain and adjacent soft-tissue swelling, but some lesions are asymptomatic. LCH can involve any bone, but most lesions occur in the skull (especially the calvarium and temporal bones), the pelvis, spine, mandible, ribs, and tubular bones. Imaging diagnosis of the disease in bone is first based on the plain radiographic appearance, which is usually a central destructive, aggressive-looking lesion. In the skull, the lesions develop in the diploic space, are lytic, and their edges may be beveled, scalloped or confluent (geographic), or show a "button sequestrum." Vertebral body involvement usually causes collapse, resulting in vertebra plana. With significant recent improvements in the quality of gamma cameras, imaging techniques, and in studying children, bone scintigraphy at diagnosis and on follow-up usually reveals the sites of active disease, especially when the involvement is polyostotic. CT and MR imaging are very useful in providing detailed cross-sectional anatomic detail of the involved bone, including the bone marrow and the adjacent soft tissues. CT is better suited for demonstrating bone detail and MR imaging for bone marrow and soft-tissue involvement.