Odontogenic cysts, odontogenic tumors, fibroosseous, and giant cell lesions of the jaws

Small central odontogenic fibroma mimicking hyperplastic dental follicle and dentigerous cyst

Central odontogenic fibroma has been defined as a benign odontogenic tumor, representing the intraosseous counterpart of a peripheral odontogenic fibroma. The odontogenic fibroma is a rare tumor. Differential diagnosis of radiolucent lesions in the molar-premolar region of mandible which involve impacted tooth may include central odontogenic fibroma, hyperplastic dental follicle, dentigerous cyst, unicystic ameloblastoma, and keratocystic odontogenic tumor. We describe an example of a small central odontogenic fibroma mimicking hyperplastic dental follicle and dentigerous cyst, resulting in uneruption of a primary tooth.

Primary ciliary dyskinesia: Kartagener syndrome with central giant cell granuloma. A case report

This paper describes a clinical case of both giant cell granuloma and Kartagener syndrome in a 15-year-old male patient, with emphasis on the radiographic aspects of this extremely unusual pathology. To our knowledge, the presence of these 2 rare clinical conditions in the same patient has not been previously reported.

A comparative immunohistochemical analysis of COX-2, p53, and Ki-67 expression in keratocystic odontogenic tumors

OBJECTIVE

The aim of the present study was to investigate the association between the expression of cyclooxygenase-2 (COX-2) in keratocystic odontogenic tumors (KCOT) and more commonly used markers, such as p53 and Ki-67.

STUDY DESIGN

Expression of cyclooxygenase-2 (COX-2) in 20 biopsy specimens of keratocystic odontogenic tumors (KCOT) has been analyzed and compared with the expression of previously reported markers Ki-67 and p53. Formalin-fixed, paraffin-embedded blocks were sectioned and used for hematoxylin-eosin (H&E) staining and incubated with anti-cox-2, anti-ki-67, and anti-p53 monoclonal antibodies for immunohistochemical examination. Detection of the COX-2 antibody was performed with the EnVision kit. Cellular staining pattern was cytoplasmatic for COX-2 and nuclear for both Ki-67 and p-53. Molecular expressions were semiquantitatively evaluated as negative (-), mild (±) or strong (+).

RESULTS

Mild to strong expression of COX-2 was observed in 20 (100%) of the cases. Fifteen (75%) of the KCOTs stained positive for p53 and 18 (90%) stained positive for Ki-67. There was no statistically relevant difference between the expressions of COX - 2, Ki-67, and p53.

CONCLUSIONS

Although COX-2 has rarely been used to assess the biological activity of the KCOT, the results portrayed in the current study and the current knowledge of the overall role known to be played by COX-2 in tumorigenesis suggest that COX-2 may be an important marker involved in the biological behavior of the KCOT. Larger studies are required to improve our knowledge of the possible role of COX-2 in the pathogenic mechanism involved in KCOT.

Biopsied jaw lesions in Kuwait: a six-year retrospective analysis

OBJECTIVES

The aim of this study was to determine the relative frequency of jaw lesions in Kuwait.

MATERIALS AND METHODS

Biopsy records and microscopic sections of all jaw biopsies seen in the Department of Histopathology at Amiri Hospital, Kuwait, during the period January 2004 to December 2009 were reviewed. The biopsies were divided into three major groups: developmental/inflammatory/reactive lesions (group 1), cystic lesions (group 2), and tumors and tumor-like lesions (group 3). Groups 2 and 3 were subdivided into odontogenic and nonodontogenic.

RESULTS

Three hundred and eighty-five cases were reviewed. Of the 385 cases, 115 (29.9%) were in group 1, 178 (46.2%) in group 2, and 92 (23.9%) in group 3. Overall, radicular cysts (n = 95; 24.7%) were the most common biopsied jaw lesions, followed by chronic apical periodontitis (n = 59; 15.3%), dentigerous cysts (n = 51; 13.2%), and keratocystic odontogenic tumors (n = 30; 7.8%). In group 1, chronic apical periodontitis was the most frequent lesion (n = 59; 51.3%). In group 2, odontogenic cysts (n = 166; 93.3%) were more frequent than nonodontogenic cysts (n = 12; 6.7%), and radicular cysts (n = 95; 53.4%) were the most frequent lesions in this group. Odontogenic tumors (n = 61; 66.3%) were more frequent than nonodontogenic tumors (n = 31; 33.7%) in group 3. Keratocystic odontogenic tumors (n = 30; 32.6%) were the most frequent type of lesion in this group, followed by ameloblastoma (n = 17; 18.5%). Only 3 malignant lesions were found in this study.

CONCLUSIONS

Cystic and inflammatory lesions of the jaw are more common than tumors and tumor-like lesions of the jaw in Kuwait. The majority of inflammatory lesions that occurred in the jaw were related to periapical inflammation. Most cystic and tumorous jaw lesions were odontogenic in origin. Locally aggressive odontogenic tumors were relatively more common than nonaggressive ones. Malignant jaw tumors were relatively rare.

Neurofibromatosis type 1 associated with bilateral central giant cell granuloma of the mandible

Neurofibromatosis type 1, or von Recklinghausen disease, is one of the most common hereditary neurocutaneous disorders in humans. Clinically, Neurofibromatosis type 1 is characterized by café-au-lait spots, freckling, skin neurofibroma, plexiform neurofibroma, bony defects, Lisch nodules and tumors of the central nervous system. Central giant cell granuloma is a benign central lesion of bone, primarily involving the jaws, of variably aggressive nature characterized by aggregates of multinucleated giant cells in a background of cellular vascular fibrous connective tissue and spindle-shaped mononuclear stromal cells. The association between neurofibromatosis and central giant cell granuloma has been reported in the literature. A case of mandibular bilateral central giant cell granuloma in a patient with Neurofibromatosis type 1 was conservatively but successfully treated by adequate surgical curettage of mandibular bone lesions.

Overexpression of matrix metalloproteinase (MMP)-1 and -9 in central giant cell lesions of the jaws: implications for clinical behavior

OBJECTIVE

The aim of this study was to investigate the relationship between the immunohistochemical expression of MMP-1 and MMP-9 with the clinical behavior of central giant cell lesions (CGCLs) of the jaws.

STUDY DESIGN

Paraffin-embedded tissue from 30 aggressive and 12 nonaggressive CGCLs was assessed for the expression of MMP-1 and MMP-9 using immunohistochemistry.

RESULTS

Although cellular immunolocalization patterns of MMP-1 and MMP-9 were similar, mean values of expression estimation/SID scores of each protease were significantly higher in aggressive CGCLs in comparison with nonaggressive lesions. Moreover, linear regression analysis showed that there was a reasonably good correlation not only between the expression estimation but also among SID scores of the 2 proteolytic enzymes.

CONCLUSION

The findings of this study suggest a role for MMP-1 and MMP-9 in the resorptive activity of different cellular groups in CGCLs and indicate that differences in immunoreactivity of these 2 proteolytic enzymes may underlie the distinct clinical behavior.

Central giant cell granuloma of the jaws

Central giant cell granuloma was classified by the World Health Organization in 2005 as a rarely aggressive idiopathic benign intraosseous lesion that occurs almost exclusively in the jaws. It occurs most frequently in young women (aged <30 y). This osteolytic lesion histologically consists of proliferation of fibrous tissue, hemorrhagic focuses, hemosiderin deposits, osteoclast-like giant cells, and reactive bone formation. Differential diagnosis has to be made with other osteolytic neoformations of the jaws, both unicystic and multicystic (odontogenic tumors, fibrous dysplasia, cysts, etc). From 2002 to 2008, we surgically treated 8 cases of giant cell granuloma. Our article focuses on a 59-year-old woman who came to our department with a swelling on the right side of the face. Computed tomography examination showed an osteolytic and expansive neoformation spreading up from the lateral wall of the nose to the anterior wall of maxillary sinus and above up to the inferior margin of the eye socket. Besides, it was contiguous to the canine root apex, the first and second bicuspids. Intraoral incisional biopsy confirmed the histologic picture of central giant cell granuloma. After a few days, she underwent surgical excision of the neoformation, preserving the lateral wall of the nose, the anterior wall of maxillary sinus, the eye socket, and the dental elements, respectively. Results of the histopathologic examination confirmed the previous biopsy. A follow-up at 30 months excluded any relapse.

Glandular odontogenic cyst involving the posterior part of maxillary sinus, a rare entity

The Glandular Odontogenic Cyst (GOC) was first coined by Gardner et al. [2], in 1988 as an odontogenic origin, is a rare developmental lesion considered a distinct entity because of its uncommon clinical and histopathological characteristics. This lesion can involve either jaws, but the anterior region of the mandible is the most affected area. It strikes distinct age groups, with an average patient age of 50 years. Radiographically, GOC does not display specific or pathognomonic features. It may present as a multilocular or unilocular radiolucencies. The cyst has an aggressive nature and high tendency of recurrence, so long-term follow-up should be carried out. The treatment is controversial, varying from conservative methods to block excision. It is believed that the low prevalence of GOC in the literature is because of not only its rarity, but principally to the fact that its main characteristics are also found in other pathological entities, thereby generating controversial diagnoses. The aim of this paper is to present a rare case of Glandular Odontogenic Cyst (GOC), which is uncommon in the posterior maxilla, that mimicks the lateral odontogenic cyst/botroid odontogenic cyst/Central Muco-epidermoid carcinoma. Owing to its tendency to recur, the lesion needs careful and meticulous planning for its surgical removal.

Characterization and management of the keratocystic odontogenic tumor in relation to its histopathological and biological features

Keratocystic odontogenic tumor (KCOT), formerly referred to as odontogenic keratocyst, is a benign neoplasm of odontogenic origin which may present an aggressive and infiltrative behavior leading to high recurrence rates. A review of the various treatment modalities, ranging from simple enucleation to radical surgery is portrayed in relation to clinical, radiological, histopathological and molecular features. Although prognostic factors based on clinico-pathologic and immunohistochemical findings for determining the potential for recurrence of KCOT still remains unclear, its use for determining the potential for recurrence of KCOT after surgical treatment may become important to successfully manage this neoplasm's aggressive behavior. The key element for future management of KCOTs will probably be based on thorough knowledge of the biological basis of this tumor, thereby enabling a more tailored treatment approach.

Central odontogenic fibroma of the mandible: a case report

Central odontogenic fibroma (COF) is a rare tumor that accounts for 0.1% of all odontogenic tumors. It has been defined as a benign neoplasm, which appears in the jaw. Clinically, the lesion grows slowly and leads to cortical expansion. Radiologically, the most common finding is multilocular radiolucency. In some cases, it may be associated with root resorption or displacement. Histologically, the lesion is characterized by mature collagen fibers and numerous fibroblasts. COF responds well to surgical enucleation with no tendency for malignancy or recurrence. Here, a case of central odontogenic fibroma of the mandible in a 71-year-old man is described. The lesion was an asymptomatic mass with well-defined borders covered by normal mucosa. The lesion presented as a multilocular radiolucency in relation to the root of the canine. The lesion was surgically removed and analyzed histopathologically. There were no postoperative complications.

Central giant cell granuloma of the jaws: clinical and radiological evaluation of 22 cases

OBJECTIVE

The objective was to investigate the clinical and radiological characteristics of central giant cell granulomas (CGCGs) of the jaws.

METHODS

A retrospective analysis of a 20-year database was performed regarding both clinical and radiological features of 22 patients affected with CGCGs of the jaws.

RESULTS

Fourteen women and 8 men were included with the age range of 7-81 years (mean 31.7 years). Among the 22 lesions, 16 were located in the mandible and 6 in the maxilla. Painless swelling was the most common clinical feature in 18 of all cases. Limited mouth opening was noted in 2 patients where the lesions involved the condyle. Radiographically, 13 lesions were homogeneously osteolytic and 9 lesions were trabeculated. Fifteen lesions were unilocular and 14 lesions presented with well-defined but not sclerotic margins. CT images in 5 patients clearly showed the trabeculation within the lesions. The follow-up ranged from 1.5 to 11 years with a mean period of 5 years. Three out of 9 aggressive and 1 out of 13 nonaggressive lesions developed recurrence.

CONCLUSIONS

Diagnosis of CGCGs of the jaws depends on both correct interpretation of clinical, radiographic and pathological data. Differentiation between aggressive and nonaggressive CGCGs should be considered to improve individual treatment planning.

Actual Proliferating Index and p53 protein expression as prognostic marker in odontogenic cysts

BACKGROUND

The purpose of this study was to evaluate the biological aggressiveness of odontogenic keratocyst/keratocystic odontogenic tumour (KCOT), radicular cyst (RC) and dentigerous cyst (DC) by observing the actual proliferative activity of epithelium, and p53 protein expression.

METHODS

The actual proliferative activity was measured by Ki-67 Labelling Index and argyrophilic nucleolar organizing regions (AgNOR) count per nucleus. The p53 protein expression was also evaluated.

RESULTS

Ki-67 positive cells were observed higher in suprabasal cell layers of KCOT with uniform distribution, a few of them were predominantly observed in basal cell layer in RC and DC. The AgNOR count was significantly higher in suprabasal cell layers of KCOT. The actual proliferative activity was noted to be higher in suprabasal cell layers of KCOT. The p53 immunolabelling was dense and scattered in basal and suprabasal cell layers in KCOT. The weakly stained p53 positive cells were observed diffusely distributed in KCOT, whereas they were mainly seen in basal cell layer of RC and DC.

CONCLUSION

The quantitative and qualitative differences of the proliferative activity and the p53 protein expression in sporadic KCOT may be associated with intrinsic growth potential that could play a role in its development and explain locally aggressive biological behaviour. AgNOR count and p53 protein detection in odontogenic lesions can be of great consequence to predict the biological behaviour and prognosis.

Glandular odontogenic cyst: report of two cases and review of literature

Glandular odontogenic cyst (GOC) is an uncommon jaw bone cyst of odontogenic origin described in 1987 by Gardner et al. It is a cyst having an unpredictable and potentially aggressive behaviour. It also has the propensity to grow to a large size and tendency to recur with only 111 cases having been reported thus far. The first case occurred in a 42-year-old female and presented as a localized swelling extending from 19 to 29 regions. There was a history of traumatic injury at the site. There was evidence of bicortical expansion and radiographs revealed a multilocular radiolucency. The second case occurred in a 21-year-old male, as a large swelling in the mandible and radiograph revealed radiolucency in the region. On histopathological examination, these lesions were diagnosed as GOC. It was concluded that, two cases submitted by us correlate with the existing literature that GOC's affect more commonly in the middle age group, having predilection for mandible and that trauma could be a precipitating factor for its occurrence. The increased recurrence rates can be due to its intrinsic biological behavior, multilocularity of the cyst, and incomplete removal of the lining following conservative treatment.

Immunoexpression of keratins in the calcifying cystic odontogenic tumor epithelium

Ameloblastomatous epithelium containing clusters of ghost cells is the typical histopathology of calcifying cystic odontogenic tumor (CCOT). This paper aimed to assess keratins AE1-AE3, K7, K10/13, K14, K18, K19, vimentin, laminin, and collagen IV in 08 CCOTs to discuss their histopathogenesis. Similarity to the immunoprofile of the stratified squamous epithelium was seen in the with the basal layer expressing K14 and the upper cells expressing K10/13. When compared to the immunoprofile of the normal odontogenic epithelium, of odontogenic tumor epithelia and of the ghost cells described in the literature, it was possible to suggest that the CCOT epithelium differentiates towards squamous type.

Hybrid central odontogenic fibroma with giant cell granuloma-like component: case report and review of literature

Central odontogenic fibroma (COF) is a rare benign ectomesenchymal tumor of the jaws. Only 12 cases of COF with giant cell granuloma (GCG)-like lesion have been reported in the English literature. Here, we present a new case of COF epithelium rich type with a GCG-like component. Radiographically, this lesion presented as a well defined unilocular radiolucency in the body of the mandible. Histologically, the lesion showed a unique confluence of odontogenic epithelial rests with multinucleated giant cells (MNGCs) in a highly cellular fibrous connective tissue stroma, with osteoid and cementoid deposits. A distinct area showed the typical histological picture of each component separately. Immunohistochemical staining with pancytokeratin (CK) highlighted the odontogenic epithelial component merging with the GCG component throughout most of the lesion. The significance of GCG-like areas within COF is the reported increased risk of recurrence following curettage, possibly necessitating more aggressive therapy.

Rare nasosinusal tumors: case series and literature review

Tumors of the nasal cavity and paranasal sinuses are unusual pathologies found in clinical practice. Approximately 0.8% of all human cancers are located in this area. Despite being rare, nasosinusal neoplasms usually manifest through nonspecific symptoms that are common to numerous inflammatory pathologies. The aim of this study is to describe a series of rare nasosinusal tumors, including esthesioneuroblastomas, central giant cell granulomas, extramedullary plasmocytomas, nasosinusal hemangiopericytomas, neurofibromas and cemento-ossifying fibromas, diagnosed at the Fortaleza General Hospital. We, hereby, briefly review each of the aforementioned pathologies, stressing the need for a precise histological diagnosis for proper treatment in each case.

Clinical Practice: Giant Cell Tumour of the Jaw Mimicking Bone Malignancy on Three-Dimensional Computed Tomography (3D CT) Reconstruction

A wide range of diseases may present with radiographic features of osteolysis. Periapical inflammation, cysts and benign tumours, bone malignancies, all of these conditions may show bone resorption on radiograph. Features of the surrounding bone, margins of the lesion, and biological behaviour including tendency to infiltration and root resorption, may represent important criteria for distinguishing benign tumours from their malign counterpart, although the radiographic aspect of the lesion is not always predictive. Therefore a critical differential diagnosis has to be reached to choose the best management. Here, we report a case of giant cell tumour (GCT) whose radiological features by computed tomography (CT) suggested the presence of bone malignancy, whereas the evaluation of a routine OPT scan comforted us about the benign nature of the lesion. A brief review of the literature on such a benign but locally aggressive neoplasm is also provided.

Tumores nasossinusais raros: série de casos e revisão de literatura

Os tumores nasossinusais são patologias pouco freqüentes na prática clínica. Aproximadamente 0,8% de todos os cânceres humanos localizam-se nessa região. Apesar de rara, a neoplasia nasossinusal manifesta-se habitualmente através de sintomas inespecíficos e comuns a inúmeras patologias inflamatórias. Este estudo se propõe a descrever uma série de casos de tumores nasossinusais não-epiteliais raros, incluindo estesioneuroblastoma, granuloma central de células gigantes, plasmocitoma extramedular, hemangiopericitoma sinonasal, neurofibroma e fibroma cemento-ossificante, diagnosticados no Hospital Geral de Fortaleza, SESA/SUS. Faz-se uma breve revisão de literatura de cada patologia, salientando-se a necessidade do diagnóstico anatomopatológico preciso para condução adequada de cada caso.

Tumor cell proliferation and microsatellite alterations in human ameloblastoma

Ameloblastoma is the most common odontogenic tumor. It can exhibit a variety of histological patterns, a great infiltrative potential and a high recurrence rate. Mutations in microsatellite sequences are a hallmark of neoplastic transformation but little is known about their role in ameloblastoma development. In this study DNA was extracted from laser-microdissected samples of 24 ameloblastomas and was analyzed for the status of 22 microsatellite loci. The occurrence and the pattern of microsatellite alterations, in form of loss or length variation, was evaluated and correlated with the Ki67 labeling index and with other clinicopathologic parameters. The prognostic significance of these alterations was also evaluated. High Ki67 expression was significantly associated with a shorter disease-free survival (p=0.003 by log-rank test). Alterations of at least one of the selected loci was observed in all (100%) the ameloblastomas analyzed with a mean of 4 altered microsatellites for each tumor. The microsatellites most frequently altered were D9S747 and D11S488 (42%). All the other loci analyzed were altered in less than 40% of cases and some of them (D3S1312, D3S1300, IFNA, D9S164, D13S176 and TP53) did not show alterations in any of the ameloblastomas analyzed. No relationship was observed between the occurrence of microsatellite alterations and other parameters, such as patients age and gender, tumor size, localization and histotype. The occurrence of microsatellite alterations was more frequent in tumors displaying a high Ki67 labeling index (p=0.03) and in a univariate analysis was predictor of an increased risk of disease recurrence (p=0.039 by log-rank test). These findings demonstrate that microsatellite alterations are frequent event in ameloblastomas. They also suggest that evaluation of tumor cells proliferative activity and microsatellite alterations may be helpful to stratify ameloblastomas prognostically and to predict the clinical behavior of these tumors.

Demographic profile of odontogenic and selected nonodontogenic cysts in a Brazilian population

OBJECTIVE

To determine the demographic profile of all histologically diagnosed odontogenic cysts (OC) and nonodontogenic cysts (nOC) over a 51-year period in the Brazilian population.

STUDY DESIGN

Case records of patients with OC and nOC from the files of the Oral Pathology Service, School of Dentistry, Federal University of Minas Gerais, Belo Horizonte, Brazil, during the period of 1953-2003 were evaluated.

RESULTS

Among 19,064 oral biopsies, 2,905 (15.2%) presented criteria of OC and nOC. Of these, 2,812 specimens (14.7%) were diagnosed as OC and 93 (0.5%) represented nOC. The 3 most frequent OC diagnosed were radicular cyst (61.0%), dentigerous cyst (25.3%), and odontogenic keratocyst (7.2%). The most frequent nOC was the nasopalatine duct cyst (2.2%).

CONCLUSION

Our results demonstrate that there is a wide range of OC and nOC, with some cysts having a predilection for age, gender, and localization. We also showed demographic aspects and clinical characteristics of these cysts. These could be used as baseline data to obtain more epidemiologic information about the OC and the nOC especially in the Brazilian population.

Localized gingival enlargement associated with alveolar process expansion: peripheral ossifying fibroma coincident with central odontogenic fibroma

BACKGROUND

Despite the common occurrence of localized gingival enlargements, which often represent reactive lesions, the temporal and spatial association of such a lesion with a central jaw lesion has not been reported. The purpose of this case report is to present the exceptional combination of a peripheral ossifying fibroma and a central odontogenic fibroma. The differential diagnosis and management of each lesion is reviewed.

METHODS

A 45-year-old black female presented with a chief complaint of a painless protuberance in the left mandible of 1-year duration. Clinical and radiographic examination revealed a gingival enlargement localized between teeth #21 and #23 and a multilocular radiolucent lesion with radiopaque foci in the same area. Excisional biopsy of the gingival lesion and incisional biopsy of the central lesion were performed, and specimens were submitted for histopathological analysis.

RESULTS

Biopsy of the gingival lesion revealed stratified squamous epithelium and highly cellular fibroblastic component presenting central areas of calcification, features consistent with a diagnosis of peripheral ossifying fibroma. The central lesion was characterized by cellular fibrous tissue admixed with rests of odontogenic epithelium and few calcification areas, features consistent with a diagnosis of central odontogenic fibroma/World Health Organization type. Subsequently, the central lesion was enucleated. After 1-year follow-up, no recurrence has been observed.

CONCLUSIONS

The combination of a rare central lesion with a common gingival lesion may present unique diagnostic and therapeutic challenges. Clinician awareness regarding the possibility of such a combined presentation and its implications will help to ensure optimal treatment outcomes.

Aspectos radiológicos e epidemiológicos do granuloma central de células gigantes

OBJETIVO: Este estudo teve como objetivo avaliar os principais aspectos radiográficos e epidemiológicos das lesões de células gigantes (granulomas centrais de células gigantes e tumores marrons do hiperparatireoidismo). MATERIAIS E MÉTODOS: A amostra consistiu de 26 lesões de células gigantes diagnosticadas em 22 pacientes divididos em dois grupos, um deles composto por 17 pacientes que não tinham hiperparatireoidismo (grupo A) e o outro formado por cinco pacientes portadores de tal distúrbio (grupo B). RESULTADOS: O sexo feminino (72,7%) foi o mais acometido. As lesões ocorreram mais freqüentemente na segunda década de vida, com média de idade de 27 anos. A mandíbula (61,5%) foi o arco mais envolvido. Radiograficamente, 57,7% das lesões eram multiloculares e 42,3% eram uniloculares com limites definidos. Todas as 26 lesões provocaram expansão óssea, 15,4% produziram reabsorção radicular, 50% causaram deslocamento dentário e 11,5% produziram dor. Na mandíbula, 18,7% das lesões cruzavam a linha média. O grupo A apresentou 66,7% das lesões na mandíbula e o grupo B mostrou igualdade na distribuição das lesões entre os arcos. O grupo A apresentou 66,7% das lesões multiloculares e 33,3%, uniloculares. O grupo B apresentou 62,5% das lesões uniloculares e 37,5%, multiloculares. CONCLUSÃO: As lesões de células gigantes podem manifestar-se, radiograficamente, com um amplo espectro, desde pequenas lesões uniloculares de crescimento lento até extensas lesões multiloculares. Elas apresentam características de benignidade, embora algumas lesões possam demonstrar um comportamento localmente agressivo.

Cystic variant of calcifying epithelial odontogenic tumor

Calcifying epithelial odontogenic tumor (CEOT) is a benign, locally aggressive odontogenic neoplasm characterized by sheets and nests of epithelial cells with deeply eosinophilic or occasionally clear cytoplasm, calcifications, and eosinophilic amorphous material that stains positive for amyloid. Although many cases of CEOT are associated with impacted teeth and occasionally appear radiographically as dentigerous cysts, a true cystic variant has not been previously reported. We report a 15-year-old white male with a large cystic maxillary lesion that filled most of the left maxillary sinus. It deformed the medial wall, the inferior orbital floor, and caused narrowing of the left inferior meatus. Histologically, the cystic lining showed characteristics of CEOT. An intraluminal component that featured histologic characteristics of CEOT was identified during surgery. The lesion was enucleated and the postsurgical course of the patient was uneventful. Because follow-up has been for less than 1 year, a meaningful long-term prognosis cannot be determined at present. However, the patient has not reported any symptoms or signs of recurrence during the follow-up period.

Zentrales Riesenzellgranulom des Unterkiefers

The synopsis of radiographic examination (uni- or multilocular radiolucency), histologic findings (giant cells throughout a benign fibroblastic matrix), blood chemistry analysis (normal serum parathyroid hormone) and clinical features provides the definitive diagnosis of giant cell granuloma, allowing the clearly defined surgical management of this lesion. The case history of a 48-year-old female patient who presented with a giant cell granuloma in the right mandible is used to illustrate this controversially discussed intra-osseous lesion. The potential therapeutic change from radical operative treatment, including functional maintenance, to conservative procedures is emphasized.

Central giant cell granuloma of the jaws: A clinical, radiologic, and histopathologic study of 26 cases

The clinical behavior of central giant cell granuloma (CGCG) of the jaws is variable and difficult to predict. Clinical data and follow-up information of 26 patients with CGCG were analyzed. Histologic features were correlated with the clinical course of the disease. In 16 patients the CGCGs were asymptomatic; 10 lesions presented with aggressive growth, pain, massive swelling, root resorption, cortical perforation, and/or recurrence. These patients were younger and the lesions were larger than in the nonaggressive group. The histomorphometric analysis proved a significant increase in large giant cells, fractional surface area, and mitotic activity in aggressive CGCG lesions. Immunohistologic investigation (Ki-67 and p53 stain) revealed no significant differences. After surgical treatment, 3 patients with aggressive lesions developed a recurrence. The data show that clinical and histomorphometric features may be reliable indicators for the differentiation between aggressive and nonaggressive CGCG. This should be accounted for to improve the individual planning of the treatment and follow-up.

Does HPV play a role in the etiopathogenesis of ameloblastoma? An immunohistochemical, in situ hybridization and polymerase chain reaction study of 18 cases using laser capture microdissection

Ameloblastomas are epithelial tumors of odontogenic origin, biologically characterized by local recurrence. Among different etiologic factors, HPV infection has been recently postulated to be somehow involved in ameloblastoma etiopathogenesis. To address this issue, we studied 18 ameloblastomas by means of immunohistochemistry, in situ hybridization (conventional and amplified), polymerase chain reaction and nested-polymerase chain reaction analyses using laser capture microdissection in order to detect the occurrence of HPV in this setting. No evidence of HPV infection was detected by morphological examination, immunohistochemistry, in situ hybridization and conventional polymerase chain reaction, while nested-polymerase chain reaction showed a weak positive band in two cases. However, the subsequent restriction enzyme analysis carried out from the nested-polymerase chain reaction amplification products of these two samples excluded the presence of HPV subtypes 16, 18, 31, 33, 35, 52, and 58. The search for HPV 6 and 11 in the same specimens was also negative. In conclusion, our data do not support an etiopathogenetic evidence for HPV in ameloblastoma.

Malignant odontogenic tumors: a 22-year experience

OBJECTIVES/HYPOTHESIS

Malignant odontogenic tumors are exceedingly rare and arise from odontogenic epithelial residues and odontogenic cysts in the jaw bones. Odontogenic malignancies have various origins. Some develop directly from the remnants of odontogenic epithelium left after completion of dental development; others may result from malignant transformation of a benign odontogenic cyst or ameloblastoma. These lesions are usually locally aggressive with radical surgery being the primary mode of treatment. Because of their rarity, much of the existing information about malignant odontogenic tumors with regard to their origin, clinicopathological features, biological behavior, and therapeutics is derived from case reports or small series. The study represents one of the largest series of malignant odontogenic tumors compiled in a single institution.

STUDY DESIGN

Retrospective 22-year review from an Academic Medical Center.

METHODS

Twenty cases of reported malignant odontogenic tumors were diagnosed in the authors' institution between 1981 and 2002. All pathological slides were reviewed to reconfirm diagnosis. Malignancy was confirmed based on the following criteria: histological findings of infiltrative growth, atypical cytological features, and focal necrosis or clear evidence of distant metastatic spread. Patient age, race, sex, treatment and outcome were recorded on chart review.

RESULTS

Of the twenty reported cases, only nine were actually found to be malignant tumors on re-evaluation. These consisted of four cases of malignant ameloblastomas, two cases of ameloblastic carcinoma, one case of malignant Pindborg tumor (calcifying epithelial odontogenic tumor), one case of odontogenic ghost cell carcinoma, and one case of squamous cell carcinoma arising in an odontogenic keratocyst. The racial demographics were six Caucasian patients, one African American patient, and two Asian patients; seven men and two women represented the gender distribution. Tumors of six cases were located in the mandible, and of three cases, in the maxilla. All cases were treated with radical surgical excision. Two patients died of their disease, three patients were alive and free of disease, and four patients were lost to follow-up.

CONCLUSION

Malignant odontogenic tumors are rare. They require a multidisciplinary team to determine proper treatment. Long-term surveillance is mandatory and is accomplished by routine physical examinations, along with serial radiographic imaging.

Free Fibula Flap Mandible Reconstruction in Benign Mandibular Lesions

The mandible may be affected by a variety of pathological conditions such as ameloblastomas, odontogenic keratocysts, central giant cell granulomas, fibro-osseous lesions, and osteomas. They generally are benign, and conservative treatment can be enough in most of the cases. However, they can be clinically aggressive, and especially ameloblastomas, odontogenic keratocysts, and fibro-osseous lesions are prone to recur. The method of treatment remains a matter of controversy in these cases. The aim of this analysis was to study 100 patients who had been treated for benign mandibular lesions, and to emphasize the importance of free fibula flap in the treatment of such lesions.

Ameloblastoma in the Hong Kong Chinese. Part 1: systematic review and clinical presentation

OBJECTIVES

The aim of Part 1 of this study was to determine the clinical presentation of central ameloblastomas in the Hong Kong Chinese and to compare them with other reported series by a systematic review (SR).

METHODS

The study had two elements, that of a complete series of all ameloblastomas presenting at a major Chinese maxillofacial surgical unit as well as a SR. The files of the Department of Oral and Maxillofacial Surgery of the University of Hong Kong between 1989 and 2000 were reviewed for ameloblastoma cases. The relevant literature was identified by electronic databases, review of citation lists and hand searching of key journals. The principal selection criterion was that the study should represent a complete collection of cases.

RESULTS

Fifty-three published series of cases were included in the SR. They generally reported little more than sex, mean age and range, and affected jaw. Only 16 studies considered recurrence. Sixty-one cases of ameloblastoma were identified in the present study. There were 30 males and 31 females, contrary to the predilection for males in other reports. Eighty-four percent of cases were found in the mandible, agreeing with the SR. The mean age at first presentation was 30.5 years, lower than that of the SR; only a Korean report and a small Bangladeshi report showed younger presentation. The present report had the shortest period between first becoming aware of the lesion and seeking treatment; this period was significantly shorter for younger patients. Although the present study was in agreement with the SR with regard to swelling, this study reported a significantly higher proportion of patients presenting with pain.

CONCLUSION

Although the presentation of ameloblastoma within this Chinese community was broadly similar to that observed in other populations, it differed in a number of important respects. It had a younger age at first presentation than many other communities, including other Orientals; it was associated with a shorter period between first becoming aware of the lesion and seeking treatment, particularly in the young; and it was more frequently associated with pain than in the SR.

Familial ossifying fibromas: report of two cases

Ossifying fibroma is a benign fibro-osseous lesion of the jaw containing varying amounts of calcified deposits such as bone, cementum or both. This type of lesion is referred to as dysplastic or neoplastic in nature. In 2000, a 52-year-old male patient was referred to our clinic complaining of a giant swelling in the mandibular premolar-molar region. A histopathological diagnosis of ossifying fibroma was made. Three months later, his daughter was admitted with a swelling on her mandible. Following biopsy, this patient was also diagnosed as having ossifying fibroma. The present report describes these two cases of familial and multiple ossifying fibromas.

Two unusual lesions in the nasal cavity of infants--a nasal chondromesenchymal hamartoma and an aneurysmal bone cyst like lesion. More closely related than we think?

Benign reparative lesions in the head and neck region in infants are rare and often difficult to classify on histology. Discussed herein are two rare lesions in infants occurring at identical locations in the nasal cavity with striking histologic similarity but different histologic labels. One was a case of nasal chondromesenchymal hamartoma (NCMH) occurring in a 1-year-old child and the other an aneurysmal bone cyst (ABC) like lesion affecting a 4-month infant. Both these lesions were locally destructive and had nearly similar clinical presentation. Both on immunohistochemistry showed myofibroblastic nature and had similar histology except that the ABC like lesion lacked the cartilage component of the former. In view of great similarity in the two lesions, it was thought that the second lesion might also represent a reparative, non-cartilage-containing counterpart of the former.

Molecular Analysis to Demonstrate That Odontogenic Keratocysts Are Neoplastic

Context.—Odontogenic keratocysts (OKCs) are unique odontogenic lesions that have the potential to behave aggressively, that can recur, and that can be associated with the nevoid basal cell carcinoma syndrome. Whether they are developmental or neoplastic continues to be debated.

Objectives.—To identify loss of heterozygosity of tumor suppressor genes in OKCs and to suggest a pathogenetic origin for these lesions.

Design.—We examined 10 OKCs for loss of heterozygosity of tumor suppressor genes, using a microdissection and semiquantitative genotyping analysis. The genes analyzed included 10 common tumor suppressor genes, as well as the PTCH gene, which is mutated in nevoid basal cell carcinoma syndrome.

Results.—Loss of heterozygosity was seen in 7 of 10 cases, with a frequency between 11% and 80% of the genes studied. The genes that exhibited the most frequent allelic losses were p16, p53, PTCH, and MCC (75%, 66%, 60%, and 60%, respectively). Daughter cysts were associated with a higher frequency of allelic loss (P = .02), but epithelial budding was not.

Conclusions.—Our study indicates that a significant number of OKCs show clonal loss of heterozygosity of common tumor suppressor genes. The finding of clonal deletion mutations of genomic DNA in these cysts supports the hypothesis that they are neoplastic rather than developmental in origin.