Fine-needle aspiration biopsy of ameloblastic carcinoma of the mandible: a case report

The use of fine-needle aspiration biopsy (FNAB) in the diagnosis of odontogenic tumors seems to have attracted little attention. The presence of a firm preoperative diagnosis helps preventing suboptimal surgery, contributing to avoid recurrence of these tumors. A case of ameloblastic carcinoma of the mandible diagnosed by FNAB is presented in this report, illustrating its effectiveness for preoperative diagnosis of odontogenic tumors. A 74-year-old female presented with a painless swelling in the right mandibular angle. A panoramic radiograph revealed a radiolucent lesion in the body of the mandible. Cytological smears from FNAB in the area revealed basaloid cells with a palisade arrangement and presence of stellate-shaped cells. These cytological features lead to the diagnosis of ameloblastoma. However, when there are atypical cells and atypical mitoses, as in the present case, diagnosis of ameloblastic carcinoma may be established. The patient underwent chemotherapy, showing remission of the lesion after treatment. FNAB is a minimally invasive, safe, fast and inexpensive method for diagnosing benign and malignant ameloblastomas, which ensures that patients have a proper treatment without the need of performing an incisional biopsy, especially in neoplastic cases.     

Squamous-cell carcinoma arising from an odontogenic cyst--the importance of computed tomography in the diagnosis of malignancy

Primary intraosseous carcinoma of the mandible is rare, and when it occurs often arises within or closely associated with an odontogenic cyst. The purpose of this article is to show the role of computed tomography (CT) in the early detection of carcinomatous changes, because of its specificity in establishing the nature of the lesion. An unusual case of a squamous cell carcinoma that arose in an odontogenic cyst is described. The appearance on the panoramic radiograph was suggestive of a benign cystic lesion in the left side of the mandible, but when a CT scan was performed, the appearance of the lesion was compatible with malignancy. Histopathological analysis confirmed the suspicion of a squamous cell carcinoma, but without CT investigation it would be impossible to demonstrate that carcinomatous change had developed from a cystic lesion.     

Maxillary ameloblastic fibroma: a case report

Ameloblastic fibroma is a relatively rare benign odontogenic tumor in which both the epithelial and ectomesenchymal components are neoplastic. An 8-year-old Caucasian boy was referred to the dentist for evaluation of failed eruption of the maxillary left first molar. The panoramic radiograph showed a well-circumscribed unilocular radiolucency involving an unerupted maxillary left first permanent molar. The lesion was enucleated and the material was sent for histopathologic examination. Microscopically, it was composed by cords and islands of odontogenic epithelium in a myxoid cell-rich stroma that closely resemble the dental papilla with histopathological diagnosis of ameloblastic fibroma. After 24 months of follow-up no recurrence was observed and the maxillary left first molar erupted spontaneously through the buccal mucosa and was aligned with a fixed orthodontic appliance. This case emphasized the importance of careful differential diagnosis of intraosseous oral lesions and reported a rarity of the lesion and its atypical location.     

Ameloblastic fibro-odontoma arising in the mandible: three case reports

Ameloblastic fibro-odontoma is a rare mixed odontogenic tumor. Here, we describe three cases of ameloblastic fibro-odontoma. We present both conventional radiography and computed tomography (CT) images from two cases and conventional radiography from one case. Given the CT values of the tumor’s radiopaque components, CT was very useful for the diagnosis of ameloblastic fibro-odontoma.     

Ameloblastic Carcinoma

Ameloblastic carcinoma (AC) is a rare aggressive malignant epithelial odontogenic tumor of the maxillofacial skeleton with a distinct predilection in the mandible. It may appear de novo or originate from a pre-existing ameloblastoma or odontogenic cyst. It exhibits cytological features of ameloblastoma and carcinoma. It may present as a cystic lesion with benign clinical features or as a large tissue mass with ulceration, significant bone resorption and tooth mobility. The clinical course of ameloblastic carcinoma is typically aggressive, with extensive local destruction. Direct extension of the tumour, lymph node involvement and metastasis to various sites has been reported. Wide local excision is the treatment of choice. Regional lymph node dissection should be considered and performed selectively. Radiotherapy and chemotherapy have limited role in the treatment of ameloblastic carcinomas. Close periodic reassessment of the patient is mandatory.     

Three-dimens?onal cone-beam computed tomography for diagnos?s of keratocystic odontogenic tumours; Evaluation of four cases

The keratocystic odontogenic tumour (KCOT), formerly known as the odontogenic keratocyst (OKC) is a benign intraosseous lesion that derives from remnants of the dental lamina. Due to its characteristics, clinical and histopathological features and various treatment approaches, this pathology is different comparing with other odontogenic cysts. Radiographically the KCOT appears as well-defined unilocular or multilocular radiolucency with thin radiopaque borders. In most cases, conventional radiographic imaging, such as panoramic views and intraoral periapical films, are adequate to determine the location and estimate the size of an KCOT. However, the clinical use for cone-beam computed tomography (CBCT) in oral and maxillofacial surgery increases and provides additional information about the contents and borders of the large lesions. In the present cases, the diagnostic performances of CBCT versus panoramic radiograph for four KCOTs were evaluated. It was concluded that appearance of lesions in the maxillofacial region could be better documented in the correct dimensions by CBCT versus panoramic radiograph. Key words:Odontogenic keratocyst, cone-beam computed tomography, three dimensional, panoramic radiograph.     

Stafne bone cavity--magnetic resonance imaging

A case of Stafne bone cavity (SBC) affecting the body of the mandible of a 51-year-old female is reported. The imaging modalities included panoramic radiograph, computed tomography (CT) and magnetic resonance (MR) imaging. Panoramic radiograph and CT were able to determine the outline of the cavity and its three dimensional shape, but failed to precisely diagnose the soft tissue content of the cavity. MR imaging demonstrated that the bony cavity is filled with soft tissue that is continuous and identical in signal with that of the submandibular salivary gland. Based on the MR imaging a diagnosis of SBC was made and no further studies or surgical treatment were initiated. MR imaging should be considered the diagnostic technique in cases where SBC is suspected. Recognition of the lesion should preclude any further treatment or surgical exploration.     

Hybrid odontogenic tumor of calcifying odontogenic cyst and ameloblastic fibroma

Odontogenic tumors composed of 2 distinct types of lesions are unusual. We report an odontogenic tumor that was composed of calcifying odontogenic cyst and ameloblastic fibroma that occurred in the right posterior maxilla of a 22-year-old Korean woman. The tumor had a cystic component with an ameloblastic epithelial lining and conglomerates of so-called ghost cells, and there were deposits of dentinoid material adjacent to the cyst. These are features characteristic of calcifying odontogenic cyst. Enamel organ-like epithelial islands were observed within a dental papilla-like stroma of the cyst wall. Additionally, a solid portion of the tumor had characteristic features of ameloblastic fibroma, i.e., a myxoid cellular stroma with numerous elongated islands of ameloblastic epithelium. Ghost cell masses were found in the area of ameloblastic fibroma as well. The distribution of the ghost cells suggests that this is a hybrid lesion rather than a collision tumor.     

Peripheral ameloblastic fibroma of the maxilla: report of a case and review of the literature

Peripheral odontogenic lesions are considered to be rare within the classification of odontogenic tumors. Also referred to as extraosseous or soft tissue odontogenic tumors, peripheral odontogenic tumors share the same histopathologic characteristics of their central or intraosseous counterparts. Ameloblastic fibroma is a rare odontogenic tumor that arises from both odontogenic epithelium and connective tissue. Only 2 cases of peripheral ameloblastic fibroma have been reported in the English-language literature, one of which did not show the classic features of an ameloblastic fibroma. In this report, we describe a rare case of a peripheral ameloblastic fibroma in the maxilla of a 3-year-old girl.     

Ameloblastic carcinoma: a case report with radiological features of computed tomography and magnetic resonance imaging and positron emission tomography

Ameloblastic carcinoma is a rare malignant odontogenic carcinoma that has metastatic potential, and because of its rare incidence, there are few reports focusing on its radiologic imaging. If it shows aggressive appearances, it can be diagnosed as malignant tumor. But in case of negative appearance, it is difficult to distinguish ameloblastic carcinoma from ameloblastoma. We report a case of ameloblastic carcinoma of the maxilla in a 76-year-old female patient with radiologic images and pathologic features.     

Limitation of panoramic radiography in diagnosing adenomatoid odontogenic tumors

Adenomatoid odontogenic tumor is frequently not diagnosed preoperatively even when radiographs are available. This study evaluates radiographic findings with special emphasis on the characteristic radiopacities of adenomatoid odontogenic tumor. In correlating radiologic findings with pathologic findings, differences in diagnostic accuracy between intraoral periapical and panoramic radiographs were found. The intraoral periapical radiograph allows perception of the radiopacities in adenomatoid odontogenic tumor as discrete foci having a flocculent pattern within radiolucency even with minimal calcified deposits. Panoramic radiography was often unable to demonstrate radiopacities in adenomatoid odontogenic tumor when the calcification was minimal. The result indicates that intraoral radiographs may be essential for correct radiographic interpretation of an adenomatoid odontogenic tumor in the presence of minimal quantities of calcified deposits.     

Feline inductive odontogenic tumor (inductive fibroameloblastoma) – a tumor unique to cats

The inductive fibroameloblastoma is a rare odontogenic tumor that occurs in young cats of either sex, predominantly in the anterior maxilla. This article critically reviews the previously published examples with emphasis on microscopic features, relationship to ameloblastic fibroma, and biologic behavior; an additional example is described. This tumor differs microscopically from human ameloblastic fibromas in that it is not well-circumscribed but rather originates multifocally within the supporting connective tissue as characteristic, spherical condensations of fibroblastic connective tissue (ectomesenchyme) associated with islands of odontogenic epithelium. Its biologic behavior requires further study but the tumor apparently is unique to cats and is distinct from human ameloblastic fibroma. Consequently, feline inductive odontogenic tumor is suggested as being a more appropriate designation than inductive fibroameloblastoma.     

Revision der WHO-Klassifikation odontogener Tumoren von 1992

The WHO classification of odontogenic tumors (1992, OT) was revised. The following main changes were proposed: (1) OT are not only "related to" odontogenic tissues but are derived from these; (2) the stroma of the epithelial tumor group (1.1.1) is of a fibrous nature and does not contain any ectomesenchymal component; (3) subtypes of ameloblastomas have to be differentiated (intra-, extraosseous, desmoplastic, unicystic); (4) eponyms are no longer used in the revised classification; (5) the AOT is reclassified as an epithelial OT; (6) a neoplastic and non-neoplastic line of the ameloblastic fibroma and ameloblastic fibrodentinoma is proposed; (7) the calcifying ghost cell odontogenic tumor is included in the classification; (8) the simple and the WHO type of odontogenic fibroma are included in the classification; (9) the classification of malignant OT is adapted from Eversole (1999) with a few changes. In particular, ameloblastic carcinoma is differentiated from malignant (metastasizing) ameloblastoma; (10) the term carcinoma in intraosseous (peripheral) ameloblastoma is introduced. Also, the malignant epithelial odontogenic ghost cell tumor is termed calcifying ghost cell odontogenic carcinoma; (11) the clear cell odontogenic tumor is termed clear cell odontogenic carcinoma; (12) the so-called pseudocysts are termed "cavities" (aneurysmal bone cavity, simple bone cavity, lingual and buccal mandibular bone cavity, focal marrow-containing jaw cavity).     

A large ameloblastic fibro-odontoma of the right mandible

The ameloblastic fibro-odontoma is a rare mixed odontogenic tumor. It occurs predominantly in children and young adults with no sex predilection and locates most often in the posterior segment of the mandible. A painless swelling is the most common clinical sign. Radiologically, ameloblastic fibro-odontoma shows a circumscribed radiolucency, which contains radio-opaque foci of various sizes and shapes. Histological examination reveals a fibrous soft tissue, islands of odontogenic epithelium and a disordered mixture of dental tissues. The tumor produces enamel or enamel matrix, dentin and cementum. The treatment of ameloblastic fibro-odontomas usually consists of enucleation or surgical curettage, which is possible due to their benign biological behaviour.     

Ameloblastic carcinoma: a clinicopathologic study and assessment of eight cases

The term ameloblastic carcinoma is differentiated from the term malignant ameloblastoma and is defined as an ameloblastoma in which there is histologic evidence of malignancy in the primary tumor or the recurrent tumor (or metastasis), regardless of whether it has metastasized. Eight cases of ameloblastic carcinoma from the Armed Forces Institute of Pathology (AFIP) are reported. The mean age of patients was 30.1 years, with no sex predilection noted. Seven cases involved the mandible and one involved the maxilla, with the posterior regions favored. The most common sign was swelling, although pain, rapid growth, trismus, and dysphonia also occurred. Lesions characteristically were evident as ill-defined destructive radiolucencies, with occasional radiopacities noted. Histologic features generally resembled those of conventional ameloblastoma but with cytologic features of epithelial malignant disease. The clinical course was uniformly aggressive with extensive local destruction and spread, frequent recurrences, and one case of neck node metastasis. The nomenclature and classification of odontogenic carcinomas are discussed, as well as entities that should be included in the differential diagnosis. Further reporting of ameloblastic carcinoma is encouraged.     

Case report of intra-osseous fibroma: a study on odontogenic and desmoplastic fibromas with a review of the literature

Intra-osseous fibromas of the jaw are classified by origin. Intra-osseous odontogenic fibromas have odontogenic epithelia, while desmoplastic fibromas do not. However, it is often difficult to determine the odontogenic origin for central fibromas. Three subjects with a diagnosis of intra-osseous fibroma were examined. Case 1 was a 35-year-old man found to have a panoramic radiograph from the right premolar to the mandibular ramus in the mandible that exhibited multilocular radiolucency. Within the radiolucency, small-radioopaque bodies were observed. Case 2 was a 13-year-old female, in whom a panoramic radiograph from the left premolar to the molar in the mandible showed multilocular radiolucency. Case 3 was a 51-year-old female who exhibited a heart-shaped radiolucency in the panoramic radiograph of the left first molar area in the mandible. We also reviewed the literature for previously reported cases of intra-osseous odontogenic and desmoplastic fibroma. In 64 cases of intra-osseous odontogenic fibroma and 68 cases of desmoplastic fibroma we extracted data on age, sex, location, and radiographic findings. Based on the analysis of the reported literature cases, re-evaluation of the patients in our study revealed that case 1 could be classified as desmoplastic fibroma, while cases 2 and 3 were intra-osseous odontogenic fibromas.     

Genetic expression profiling of six odontogenic tumors

Odontogenic tumors are rare neoplasms arising from the odontogenic apparatus. We aimed to identify molecular characteristics associated with odontogenic tumorigenesis and malignancy. To this end, we investigated the expression level of human genes by using, for the first time in odontogenic tumors, the technique of expression profiling. Gene expression alterations common to all six odontogenic tumors were identified by the use of cDNA microarrays containing 19,000 human cDNAs. Statistical analysis on a subset of 4974 cDNAs present in the biopsies identified 506 distinct genes associated with the tumors (p-value < 0.01). Gene ontology analysis of the cellular processes which were differentially regulated in odontogenic tumors was accomplished by the use of a subset of 1409 annotated genes. Finally, 43 cDNAs differentiated the three malignant odontogenic tumors (ameloblastic carcinoma, clear cell odontogenic tumor, granular cell odontogenic tumor) from the three benign ameloblastoma biopsies (p < 0.01). The identified genes might help us better classify borderline odontogenic tumors.     

牙源性肿瘤的印片细胞学与组织学比较的探讨

本文对35例牙源性肿瘤的印片细胞学及组织学图像进行了比较性探讨。体会到印片细胞学不仅方便、快捷，可以鉴别组织类型。并且牙源性肿瘤为颌骨内肿瘤，不方便做术前活检；肿瘤内含有骨小梁及钙化物，又不能做冰冻切片。而在手术中取材用印片细胞学进行快速诊断，指导制订治疗计划，有其特殊的，不可替代的优点，值得向同道们介绍推广。     

CEA immunoreactivity in odontogenic tumors and keratocysts

Forty-five oral tumors and cysts were stained immunohistochemically for the presence of carcinoembryonic antigen (CEA). CEA, or a CEA-like antigen that is not nonspecific cross-reacting antigen (NCA), was demonstrated in the majority of aggressive or malignant tumors showing squamous differentiation, including cases of ameloblastoma, odontogenic carcinoma, and squamous carcinoma. CEA immunoreactivity was also found in cases of odontogenic keratocyst and focally in squamous odontogenic tumors but was not found in any of the ameloblastic fibromas, myxofibromas, odontogenic adenomatoid tumors, malignant melanomas, or apical cysts.     

Ameloblastic fibro-odontoma: a case report

The clinical case of an unusual ameloblastic fibro-odontoma (AFO) was reported. The patient's clinical chart as well as preoperative and postoperative radiographs and histological findings of a 20-year old man that addressed Dental Clinic at University of L'Aquila were thoroughly reviewed. The patient showed a swelling in the oral cavity and radiographic feature of a radiolucent lesion at left second premolar maxillary site. Histologic examination made diagnosis of AFO. AFO is a rare mixed odontogenic tumor with similarities to the ameloblastic fibroma (AF) and ameloblastic dentinoma. The nature and the relationships between mixed odontogenic tumours and related lesions are still controversial. Moreover is not clear if these lesions are separate pathologies or if they are different development stages of the same pathology.