下颌骨成釉细胞癌1例报告及文献复习

成釉细胞癌是一种罕见的恶性骨内肿瘤,目前文献报告例数较少,因而该疾病的流行病学、治疗方式以及预后仍不清楚。作者报告成釉细胞癌1例,采用病灶及病灶周围2cm颌骨、软组织扩大切除方式,病理检查证实为成釉细胞癌,术后未行放疗或化疗。目前患者正随访中,无复发及远处转移迹象。     

Ameloblastic carcinoma of the maxilla metastatic to the mandible. Case report

A case of maxillary ameloblastic carcinoma metastatic to the mandible is presented. Of 33 cases of ameloblastic carcinoma reported in the English literature 10 have occurred in the maxilla. Of these, none produced mandibular metastases. The authors review the literature, describing clinical presentation, histological appearance, and treatment of this rare lesion.     

Odontogenic carcinoma arising from ameloblastoma

A case of odontogenic carcinoma of the mandible is reported. Clinical and microscopic evaluations of the case are suggestive of a specific diagnosis of ameloblastic carcinoma. The case occurs at a lower age than previously reported for ameloblastic carcinoma. There has been no recurrence three years following treatment with a combination of surgery and radiotherapy.     

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.     

Ameloblastic carcinoma, secondary type: a case report

Malignant variants of ameloblastoma include metastasizing ameloblastoma, which microscopically appears benign but has metastasized and ameloblastic carcinoma that exhibits malignant histopathologic features. Ameloblastic carcinoma is classified into 2 types: a primary odontogenic malignancy and a secondary type resulting from malignant transformation of ameloblastoma. Most secondary ameloblastic carcinomas result from malignant transformation of a primary lesion after repeated postsurgical recurrences. Therefore it is rare to find an untreated secondary type presenting with histologic features of malignant transformation from an earlier benign lesion. We experienced a rare case of ameloblastic carcinoma, secondary type which might arise in an untreated ameloblastoma. The mechanism by which a preexisting benign ameloblastoma goes through a malignant transformation is also described.     

Ameloblastic carcinoma. Report of an aggressive case and review of the literature

Odontogenic carcinomas of the jaws are classified as malignant ameloblastoma, ameloblastic carcinoma or primary intraosseous carcinoma. Because these lesions are extremely rare, microscopic diagnosis is difficult. An aggressive case of ameloblastic carcinoma of the mandible is presented. In spite of radical surgery and radiotherapy, the patient expired eight months following initial diagnosis. - A review of the literature seems to indicate that so called simple ameloblastomas rarely can dedifferentiate and metastasize following multiple inadequate surgical procedures. Although radical surgery is not necessary, local excision should be thorough. - Ameloblastic carcinoma and primary intraosseous carcinomas may be histogenetically similar. They are highly malignant tumours which should be treated aggressively. Metastasis is common and prognosis is poor.     

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.     

RECK基因和基质金属蛋白酶-2在成釉细胞瘤的表达及相关性研究

目的探讨RECK和基质金属蛋白酶-2（MMP-2）的表达与成釉细胞瘤（AB）临床生物学行为的关系及相关性。方法应用免疫组化EliVision^TM plus法检测69例AB（原发45例,复发24例）、6例成釉细胞癌和16例牙源性角化囊性瘤（KCOT）中RECK、MMP-2蛋白的表达,同时采用RT-PCR方法检测22例AB（原发12例,复发10例）、2例成釉细胞癌和16例KCOT中RECK、MMP-2mRNA的表达水平。所有数据采用SPSS13．0统计软件包进行统计学分析。结果RECK蛋白的阳性表达率在KCOT、AB和成釉细胞癌中依次明显降低（P〈0．05）,且复发AB显著低于原发AB（P〈0．01）;AB和成釉细胞癌的MMP-2蛋白阳性表达率均显著高于KCOT（P〈0．05）：RECK蛋白与MMP-2蛋白在AB中的表达呈负相关（r=-0．431,P〈0．001）。RECKmRNA在AB、KCOT中均见表达,但在AB的表达较KCOT显著降低（P〈0．001）．成釉细胞癌中则无表达：MMP-2mRNA在KCOT、AB和成釉细胞癌中均见表达,但在AB的表达水平较KCOT显著增高（P〈0．001）,在成釉细胞癌中均呈高水平表达：复发AB的RECKmRNA表达水平较原发AB显著降低（P〈0．05）,但复发与原发AB的MMP-2mRNA表达之间差异无统计学意义：RECKmRNA与MMP-2mRNA在AB中的表达水平无相关性（P〉0．05）。结论RECK表达降低或缺失及MMP-2表达增高与AB的临床生物学行为密切相关。RECK可能通过转录后水平调控MMP-2参与AB的侵润、复发和恶性转化过程。     

Ameloblastic carcinoma: case report and literature review

Ameloblastic carcinoma is a rare malignant lesion with characteristic histologic features and behaviour that dictates a more aggressive surgical approach than that of a simple ameloblastoma. However, reliable evidence of its biologic activity is currently unavailable due to the scarcity of well-documented cases. It occurs primarily in the mandible in a wide range of age groups; no sex or race predilection has been noted. 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. Because the lesion is usually found unexpectedly after an incisional biopsy or the removal of a cyst, a guide to differential diagnosis is not usually useful. The identifying features of ameloblastic carcinoma must be known and recognized by dental practitioners. Our understanding of the histologic features of ameloblastic carcinoma is somewhat vague. The tumour cells resemble the cells seen in ameloblastoma, but they show cytologic atypia. Moreover, they lack the characteristic arrangement seen in ameloblastoma. 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 (frequently the lung) have been reported. Wide local excision is the treatment of choice. Regional lymph node dissection should be considered and performed selectively. Radiotherapy and chemotherapy seem to be of limited value for the treatment of ameloblastic carcinomas. At the moment, there are too few reported cases to make a definite recommendation regarding treatment. Close periodic reassessment of the patient is mandatory.     

Ameloblastic carcinoma of the mandible resembling odontogenic cyst in a panoramic radiograph

Ameloblastic carcinoma is a rare odontogenic tumor exhibiting histologic evidence of malignancy in the primary or recurrent tumor, regardless of whether it has metastasized or not. Most ameloblastic carcinomas are presumed to have arisen de novo, with few cases of malignant transformation of ameloblastoma being apparent. A case is reported of a 21-year-old caucasian female with ameloblastic carcinoma in the left angulus area of the mandible resembling an odontogenic cyst in the panoramic radiograph. In addition to the panoramic radiograph, computerized tomography (CT) and magnetic resonance (MR) images were taken preoperatively. This report demonstrates that CT or MR examinations may be crucial in differentiating odontogenic tumors from cysts.     

Ameloblastic carcinoma: case report and review

The histologic classification for odontogenic carcinomas is still under revision; thus, the differentiation between the terms "malignant ameloblastoma" and "ameloblastic carcinoma" has not been definitely stated. Nevertheless, it is recommended to reserve the former for those lesions that, in spite of an apparently innocuous histology, have given origin to metastatic growths, and to apply the latter for those ameloblastomas in which there is histologic evidence of malignancy in the primary, recurrent or metastatic lesions. A case of an ameloblastic carcinoma in the mandible is presented. Histologically, it was characterized by areas with features of a typical ameloblastoma and areas with anaplastic appearances.     

RECK在成釉细胞瘤中的表达及其与基质金属蛋白酶-2的关系

目的:研究RECK(reversion-inducing cysteine rich protein with Kazal motifs)和基质金属蛋白酶-2(matrixmetalloproteinase-2,MMP-2)在成釉细胞瘤(ameloblastoma,AB)中的表达及其相关性,探讨两者与成釉细胞瘤临床生物学行为的关系.方法:应用免疫组化EliVisionTM plus法,检测69例成釉细胞瘤(原发AB 45例,复发AB 24例)、6例成釉细胞癌和16例牙源性角化囊性瘤(keratocystic odontogenic tumor,KCOT)中RECK、MMP-2蛋白的表达,采用SPSS13.0软件包对数据进行统计学分析.结果:RECK在KCOT、AB和成釉细胞癌中的阳性表达率依次降低,组间比较差异均有统计学意义(P<0.05),且复发AB的RECK表达显著低于原发AB(P<0.01).MMP-2在AB和成釉细胞癌中的阳性表达率均显著高于KCOT(P<0.05),且MMP-2的表达在AB与成釉细胞癌以及原发AB与复发AB间均无显著性差异(P>0.05).RECK与MMP-2在AB中的表达呈负相关(r=-0.431,P<0.001).结论:RECK与AB的临床生物学行为密切相关,可能通过调控MMP-2参与AB的浸润、复发和恶性转化过程.     

Immunohistochemical detection of uPA, uPAR, PAI-1, and maspin in ameloblastic tumors

BACKGROUND: To evaluate the roles of extracellular matrix (ECM)-degrading serine proteinase in progression of odontogenic tumors, expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), and maspin was analyzed in ameloblastic tumors as well as in tooth germs. METHODS: Tissue specimens of 10 tooth germs, 45 ameloblastomas, and 5 malignant ameloblastic tumors were examined immunohistochemically with the use of antibodies against uPA, uPAR, PAI-1, and maspin. RESULTS: Immunohistochemical reactivity for uPA, uPAR, PAI-1, and maspin was detected in normal and neoplastic odontogenic tissues: uPA was recognized predominantly in mesenchymal cells, uPAR was evident in epithelial cells, PAI-1 was found in both epithelial and mesenchymal cells, and maspin was expressed only in epithelial cells. The levels of uPA and uPAR immunoreactivity in ameloblastic tumors were slightly higher than the levels in tooth germs, while PAI-1 reactivity in ameloblastomas tended to be lower than that in tooth germs. The level of maspin immunoreactivity in ameloblastomas was significantly higher than that in tooth germs, and ameloblastic carcinoma showed decreased maspin reactivity. CONCLUSION: Expression of uPA, uPAR, PAI-1, and maspin in tooth germs and ameloblastic tumors suggests that interactions among these molecules contribute to ECM degradation and cell migration during tooth development and tumor progression. Altered expression of the serine proteinase and its associated molecules in ameloblastic tumors may be involved in oncogenesis of odontogenic epithelium.     

Ameloblastic carcinoma ex ameloblastoma of the mandible with malignancy-associated hypercalcemia

Ameloblastoma is a rare, locally destructive, benign neoplasm of the jawbones, which arises from epithelium derived from the epithelial components of the developing tooth. Ameloblastic carcinoma is the term used to designate any ameloblastoma in which there is histologic evidence of malignancy in the primary tumor, regardless of whether it has metastasized. Most ameloblastic carcinomas are presumed to have arisen de novo, with few cases of malignant transformation of ameloblastoma being apparent. Hypercalcemia is the most common metabolic complication of malignancy. Although malignancy-associated hypercalcemia is often reported in association with other malignancies, it is exceedingly unusual in association with ameloblastoma, malignant ameloblastoma, or ameloblastic carcinoma. We describe a patient with multiple recurrences of ameloblastoma, with subsequent malignant transformation presenting with malignancy-associated hypercalcemia.     

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.     

Huge ameloblastic carcinoma of the mandible with metastases treated in several different ways

Ameloblastic carcinoma is an extremely rare, aggressive, malignant tumour that is most common in the mandible. Because of its rarity there is no general approach to treatment. We present a rare case of an ameloblastic carcinoma with multiple metastases in a 63-year-old Japanese man that was treated in several different ways, including chemoradiotherapy and immunotherapy.     

The use of Gamma Knife stereotactic radiosurgery in the treatment of ameloblastic carcinoma

A case of recurrent maxillary ameloblastic carcinoma treated with Gamma Knife stereotactic radiosurgery is reported. This case demonstrates an alternative treatment modality that has not been described previously for this rare and often difficult to treat odontogenic malignancy.     

Ameloblastic Carcinoma of the mandible

Odontogenic carcinomas are rare lesions arising from dental embryogenic residues and have been designated by a variety of terms like malignant ameloblastoma, ameloblastic carcinoma, metastatic ameloblastoma or primary intra-alveolar epidermoid carcinoma. Ameloblastic carcinoma combines the histological features of ameloblastoma with cytological atypia, even in the absence of metastasis. The lesion has been reported to arise either from the odontogenic cyst or the ameloblastoma. Majority originate de novo and the remaining are malignant transformation of an ameloblastoma.     

Odontogenic lesions in opercula of permanent molars delayed in eruption

Opercula of permanent first and second molars delayed in eruption were investigated histologically to detect possible causes of eruption failure. The material comprised operation specimens from exposure of 74 non-erupted molars in 63 young individuals (34 boys, 29 girls). Eighteen of the 74 specimens (or 24.3%) were diagnosed as "classical" odontogenic tumors belonging to the following entities: ameloblastic fibroma (seven), ameloblastic fibrodentinoma (six), ameloblastic fibro-odontoma (four) and complex odontoma (one). Twenty-two specimens (or 29.7%) showed a hitherto unrecognized odontogenic lesion of hamartomatous character, termed odontogenic giant cell fibromatosis (OGCF). Thus, 54.1% of the specimens could be diagnosed as odontogenic tumors or hamartomas. Histomorphologic changes could not be detected in the remaining 34 specimens (45.9%). Odontogenic tumors were associated with unerupted first molars much more frequently than with second molars (ratio 8:1). The OGCF had a strong association with unerupted mandibular molars. Further, opercula of mandibular first molars frequently revealed odontogenic lesions whereas tissue overlying the crown of unerupted maxillary second molars often was reported as normal operculum.