1/78. ameloblastoma with basal cell carcinoma-like feature emerging as a nasal polyp.A case of a 63-year-old man with ameloblastoma with basal cell carcinoma (BCC)-like features clinically emerging as a nasal polyp is reported. The left nasal cavity was filled with a solid mass, which seemed to be a sinusitis-associated nasal polyp. The polyp was covered by parakeratotic squamous epithelium which was directly connected to the BCC-like tumor nest. The BCC-like features gradually changed to adamantinoid features. The polyp was connected with a huge mass filling the maxillary sinus and the molar area, which consisted of conventional ameloblastoma features. Although the tumor was finally diagnosed as an ameloblastoma of the maxilla, the biopsy specimen forced us to face the problem of differential diagnosis, ameloblastoma with BCC-like features or adamantinoid basal cell carcinoma (BCC). Immunohistochemical examination revealed that tumor cells of the ameloblastoma reacted with anticytokeratin antibody KL-1 but not with antiepithelial antibody Ber-EP4, and these reaction patterns were completely contrary to those of BCC. It is emphasized that immunohistochemical examination using anticytokeratin antibody KL-1 and antiepithelial antibody Ber-EP4 is a good tool for distinguishing ameloblastoma with BCC-like features from adamantinoid BCC.- - - - - - - - - - ranking = 1keywords = carcinoma (Clic here for more details about this article) |
2/78. Cytology of recurrent ameloblastoma with malignant change. A case report.BACKGROUND: ameloblastoma is a rare tumor of the jaw that arises from the odontogenic epithelium. Ameloblastomas have a propensity for local recurrence and, rarely, for metastasis. The term malignant ameloblastoma is reserved for those metastasizing tumors that retain the typical morphology of ameloblastoma. Fine needle aspiration (FNA) reports on ameloblastomas are scant, and those on malignant ameloblastomas are still more so. CASE: In a case of malignant ameloblastoma diagnosed by FNA cytology, the clinical presentation was that of a malignant neoplasm. FNA smears were highly cellular and showed isolated, scattered cells and small groups of basaloid cells and polygonal squamous epithelial cells. Stellate and spindle-shaped cells were also seen in the background. The cytologic diagnosis was subsequently confirmed on histopathology. CONCLUSION: The characteristic combination of cells in FNA smears facilitated the diagnosis of ameloblastoma. Since the biologic behavior of the tumor was that of a malignant neoplasm, the slides were reviewed. The cytologic smears did not exhibit sufficient features of malignancy to label the lesion malignant.- - - - - - - - - - ranking = 0.0078360023942346keywords = neoplasm (Clic here for more details about this article) |
3/78. Intraosseous squamous cell carcinoma arising in association with a squamous odontogenic tumour of the mandible.We report a rare occurrence of intraosseous squamous cell carcinoma (SCC) arising in association with a squamous odontogenic tumour (SOT), which had not previously been documented in the literature. A 53-year-old man had, for 5 years, a well-demarcated radiolucency attached to the impacted third molar of the mandible. The enucleated specimen had a characteristic pattern of SOT, but in which a few epithelial islands showed atypical features suggestive of SCC. Intense p53-, proliferating cell nuclear antigen- and Ki-67-positive cells were detected in carcinoma areas. Within 2 months, aggressive bone destruction showing typical findings of intraosseous SCC appeared. The present tumour is presumably a malignant variant of SOT.- - - - - - - - - - ranking = 1keywords = carcinoma (Clic here for more details about this article) |
4/78. 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 = 0.16666666666667keywords = carcinoma (Clic here for more details about this article) |
5/78. 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.- - - - - - - - - - ranking = 1.1705846678638keywords = carcinoma, neoplasm (Clic here for more details about this article) |
6/78. Extra copies of chromosomes 7, 8, 12, 19, and 21 are recurrent in adamantinoma.adamantinoma of long bones is a rare neoplasm predominantly involving the tibia. Cytogenetic studies of adamantinoma are few. Cytogenetic or molecular cytogenetic analysis of four adamantinomas, and a review of eleven cases in the literature reveals extra copies of chromosomes 7, 8, 12, 19, and 21 as recurrent in this neoplasm. adamantinoma may be confused with a variety of primary and metastatic epithelial and mesenchymal neoplasms. observation of these aneuploidies may be useful in establishing the diagnosis of adamantinoma.- - - - - - - - - - ranking = 0.011754003591352keywords = neoplasm (Clic here for more details about this article) |
7/78. Clear-cell odontogenic carcinoma with pulmonary metastases resembling pulmonary meningothelial-like nodules.Clear-cell odontogenic carcinoma (CCOC) is a rare neoplasm with malignant potential and unknown cytogenetic alterations. We describe the case of a 43-year-old woman who presented with an unusual odontogenic epithelial tumor. Histologically, the tumor was composed of clear-cell areas and exhibited a squamous pattern with little nuclear pleomorphism similar to benign squamous odontogenic tumor. Multiple small pulmonary nodules occurring 3 years after primary surgical treatment histologically closely resembled benign minute pulmonary meningothelial-like nodules (MPMN) with clear-cell features. comparative genomic hybridization (CGH) and immunohistochemistry, performed as diagnostic adjuncts, revealed in the odontogenic tumor and the pulmonary lesions a very similar pattern of chromosomal aberrations (loss of 9, gains of 14q, 19 and 20 in both, and additional loss of 6 in the odontogenic tumor) and the same pattern of expression (positive for cytokeratin 5, 6, 8, 19 and negative for cytokeratin 18, epithelial membrane antigen, and vimentin), differing from that of MPMN. These findings confirmed the final diagnosis of metastasizing CCOC with partial squamous differentiation, substantiated the unfavorable prognosis of the clear-cell component, and highlighted the diagnostic impact of CGH and immunohistochemistry for classification of these morphologically peculiar pulmonary CCOC metastases.- - - - - - - - - - ranking = 0.83725133453045keywords = carcinoma, neoplasm (Clic here for more details about this article) |
8/78. Aggressive osteoblastoma of the mandible closely simulating calcifying epithelial odontogenic tumor. Report of two cases with unusual histopathologic findings.Aggressive osteoblastoma is a rare bone-forming neoplasm composed of prominent epithelioid cells that demonstrate locally invasive growth with a high rate of recurrence but no metastatic potential. Clinical, radiographic and pathologic features of mandibular aggressive osteoblastoma in a 21-year-old African-American male and a 12-year-old Caucasian female are presented. Both tumors were resected with wide surgical margins and neither patient had adjuvant radiation or chemotherapy. The patients showed no evidence of local recurrence or distant spread either clinically or radiographically after two years of follow-up. These tumors were composed of solid sheets of pleomorphic epithelioid cells, eosinophilic amorphous osteoid with foci of calcification, which closely simulated amyloid. Differentiation of this tumor from histologically similar calcifying epithelial odontogenic tumor and low-grade osteosarcoma proved difficult. Immunohistochemical study with osteocalcin confirmed the osteoblastic nature of these epithelioid cells.- - - - - - - - - - ranking = 0.0039180011971173keywords = neoplasm (Clic here for more details about this article) |
9/78. Malignant ameloblastoma: classification, diagnostic, and therapeutic challenges.ameloblastoma is a benign odontogenic neoplasm of the mandible and maxilla that rarely exhibits malignant behavior. We report the case of an aggressive malignant ameloblastoma of the mandible that presented with an unusual multiphasic, histologic pattern. Initial fine needle aspiration and radiographic findings showed features consistent with a benign, fibro-osseous lesion. However, aggressive growth and the association of enlarged submandibular lymph nodes suggested a more malignant potential. Treatment consisted of an angle-to-angle composite mandibular resection, right modified neck dissection, left functional supraomohyoid neck dissection, and anterior chin skin resection with iliac crest osteocutaneous free flap reconstruction. Microscopic evaluation showed primarily malignant ameloblastoma without cellular atypia and extensive fields of fibro-osseous tissue with smaller fields of clear cell odontogenic tumor. This multiphasic, histologic arrangement may explain the perplexing preoperative microscopic diagnosis, suggesting a benign fibro-osseous lesion. Of the lymph nodes analyzed, one from the right submandibular triangle exhibited metastatic, benign-appearing ameloblastoma without fibro-osseous or clear cell features. The absence of cellular features of malignancy in the tumor mass and lymph node metastasis suggest that the lesion should be classified as malignant ameloblastoma rather than ameloblastic carcinoma or odontogenic carcinoma. A malignant ameloblastoma with all 3 of the aforementioned microscopic features has not been previously reported. We review the classification of epithelial odontogenic malignancies. Lesions showing multiphasic patterns can create diagnostic dilemmas and may require extensive surgical sampling and/or removal to establish an accurate diagnosis.- - - - - - - - - - ranking = 0.33725133453045keywords = carcinoma, neoplasm (Clic here for more details about this article) |
10/78. Papilliferous keratoameloblastoma of mandible: a papillary ameloblastic carcinoma: report of a case with a 6-year follow-up and review of the literature.We report a fourth case of papilliferous keratoameloblastoma, with a 6-year follow-up. A 62-year-old man underwent resection of a right mandibular neoplasm infiltrating bone and soft tissues. Microscopically, there were cysts lined by papillary projections and containing necrotic debris. Cribriform, solid, and tubular patterns were also present. No regional or distant metastases were found. A local recurrence, developed 3 years later, showed a predominance of the lesser differentiated patterns and focal granular cell ameloblastomatous features. The patient died soon after surgery of unrelated causes, with a further local relapse. The tumor coexpressed cytokeratins and vimentin, and S100 protein (the latter focally in the relapse). It was instead unreactive for alcian blue, actin, maspin, and GFAP. We suggest that papilliferous keratoameloblastoma be renamed "papillary ameloblastic carcinoma."- - - - - - - - - - ranking = 0.83725133453045keywords = carcinoma, neoplasm (Clic here for more details about this article) |
| | Next -> |