1/14. Odontoameloblastoma: report of a case.Odontoameloblastoma is a very rare odontogenic tumour that is similar to ameloblastoma in its locally aggressive behaviour. Its clinical presentation, however, often mimics the more innocuous odontoma, and hence the recognition of its aggressive nature is commonly only ascertained after its histopathologic diagnosis following enucleation. This paper presents a case of odontoameloblastoma. Some of the difficulties that may be encountered in the diagnosis and treatment planning of odontoameloblastomas are discussed.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
2/14. ameloblastoma of the jaws.ameloblastoma is a histologically benign tumor derived from odontogenic apparatus. The tumor can infiltrate into surrounding tissues. Although it is benign, it presents symptoms of a malignant tumor, such as infiltration into the lungs, pleura, regional and distant metastases, orbit, base of skull, brain and has resulted in death. It also has a high incidence of recurrences, the existence of regional or distant metastasis, showing a microscopic pattern of ameloblastic carcinoma with cytologic features of an increasing nuclear/cytoplastic ratio, nuclear hyperchromatism, and the presence of mitosis. We report a study of 12 patients of ameloblastoma of the jaws between January 1992 and December 1996 consisting of 8 affected in the mandible and 4 in the maxilla. One patient with a tumor in the maxilla was excluded from this study, due to a different histological and clinical behaviour of the ameloblastoma.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
3/14. Unusual jaw lesions in the paediatric and adolescent patient: a management challenge.While major maxillofacial pathology in the young patient is relatively uncommon, non-malignant conditions may pose a significant treatment dilemma due to their aggressive or unpredictable behaviour. Several such diseases managed by the Oral and Maxillofacial Surgery Unit at the Royal Children's Hospital of Melbourne have been selected for review. Illustrative case reports to highlight the principles of management are presented.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
4/14. Genetic portrait of malignant granular cell odontogenic tumour.Odontogenic tumours are rare neoplasms whose classification is sometime controversial. Among these entities, granular cell odontogenic tumour (GCOT) is extremely rare and usually has a benign clinical behaviour. While the histogenesis of GCOT remains to be clarified, we documented the existence of a malignant counterpart of this neoplasm and proposed the name of malignant GCOT. Expression profiling by cDNA microarrays is a molecular technology that enables a global gene expression analysis. By using cDNA microarrays, we identified in malignant GCOT several genes with significantly differentially regulated genes when compared to non neoplastic tissues. These cancer specific genes include a range of functional activities: (1) transcription, (2) signaling transduction, (3) cell-cycle regulation, (4) apoptosis, (5) differentiation and (6) angiogenesis. In conclusion, we show that cDNA microarrays is a useful approach to investigate the biology of tumours. Moreover, this technology might lead to identification of gene targets for cancer therapy and to molecular classification of odontogenic tumours.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
5/14. Central granular cell odontogenic tumour: report of the first malignant case and review of the literature.Granular cell odontogenic tumours (GCOT) are rare neoplasms that usually manifest a benign clinical behaviour. We document the first case of GCOT exhibiting clinico-pathological features of malignancy that occurred in the maxilla of a 40-year-old male. The lesion appeared as an intra-oral polypoid mass and, at CT scan, as a poorly demarcated radiolucency eroding the cortical plate. Histologically, the tumour consisted of clusters of granular cells, exhibiting nuclear pleomorphism, prominent nucleoli and mitotic figures, and spindle cells in a collagenous stroma containing cementicles and strands of odontogenic epithelium. Morphologic transition from fibroblast-like to granular cells was frequently detected. The tumour cells extensively invaded the oral and respiratory mucosae and the adjacent soft tissues and exhibited vimentin and CD 68 immunoreactivity and high (21%) Ki 67 immunolabeling but not cytokeratins, E.M.A. actin, desmin, myosin or S-100 protein positivity. The patient experienced tumour recurrence 16 months after radical surgery. While the histogenesis of GCOT remains to be clarified, we document the existence of a malignant counterpart of this tumour and propose the name of malignant GCOT or granular cell odontogenic sarcoma for such entity.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
6/14. Peripheral myxoma of maxilla. A case report.The intra-oral soft tissue myxoma or peripheral myxoma is a rare, slowly growing, benign mesenchymal tumor. Pathologically, it may be difficult to differentiate from other tumors with myoxid stroma and is occasionally misinterpreted as malignant. Though its counterpart, central odontogenic myxoma shows aggressive local behaviour and high recurrence rate following conservative excision, no much detail is available regarding peripheral myxoma of the oral cavity in the published English literature. In this paper, a rare case of peripheral myxoma of maxilla in a 35 years old female is presented with emphasis on review of relevant literature, histological aspects in differential diagnosis and 'semi-radical approach' in its management.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
7/14. 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.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
8/14. Calcifying and keratinizing ameloblastoma of the maxilla.A case is described of ameloblastoma of maxilla presenting with numerous calcified keratin pearls. The significance of cellular variation in relation to the behavioural potential of the ameloblastoma in general is briefly discussed.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
9/14. Aggressive calcifying odontogenic cyst--a possible variant of ameloblastoma.A case of an aggressive calcifying odontogenic cyst of the maxilla is presented. It recurred twice after surgical excision over the course of a year and was subsequently treated by maxillectomy followed by radiotherapy. The current histological criteria for the diagnosis of calcifying odontogenic cyst were satisfied but it is argued that they are drawn too widely. Since the majority of calcifying odontogenic cysts are benign in behaviour the presence of cytological indicators of local destruction and invasiveness alongside the usual features of calcifying odontogenic cysts (presence of dentinoid, epithelial ghost-cell degeneration) should be the over-riding prognostic considerations and should thus be reflected in the diagnostic title. Such tumours are best regarded as variants of ameloblastoma rather than as unusually aggressive forms of calcifying odontogenic cyst and an appropriate name would be 'dentinogenic ghost-cell ameloblastoma'.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
10/14. Combined calcifying epithelial odontogenic tumor and adenomatoid odontogenic tumor.A case of combined epithelial odontogenic tumor associated with an unerupted maxillary canine tooth is described. The relative proportion of adenomatoid odontogenic tumor tissue and calcifying epithelial odontogenic tumor areas in a given tumor in determining the behaviour and growth potential of this entity is discussed.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
| | Next -> |