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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a case of distant cutaneous metastases in a 68-year-old patient with malignant ameloblastoma of the mandible. The metastatic lesions were first noted approximately 31 years after resection of the primary tumor. Metastases to lung, pleura, bone, and brain had also occurred. Histochemical findings differ from those described in adamantinoid basal cell carcinoma. Cutaneous metastasis probably resulted from hematogenous dissemination. To our knowledge, this is the first report of such an occurrence in English language literature.
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PMID:Distant skin metastases in a long-term survivor of malignant ameloblastoma. 378 76

The extent of basement membrane confinement among 5 cases of ameloblastoma and a malignant counterpart were studied by immunohistochemistry. For these studies, antibodies to 2 basement membrane components, Type IV collagen and laminin, were studied by immunohistochemistry. Our results show that the tumor islands of ameloblastomas are circumferentially delineated by a linear staining to both antibasement membrane antibodies, and that these findings were consistent for all of the patterns of ameloblastoma investigated. These data suggest that ameloblastomas spread into tissue spaces by expanding their compartmental volumes rather than by secreting proteinases that disrupt their basement membranes compartmental barriers. In contrast, the single case of malignant ameloblastoma investigated was not delineated by circumferential linear basement membrane components. However, this tumor and all of its metastases did contain numerous focal areas of Type IV collagen and laminin immunoreactive materials. Collectively, these studies indicate that the use of specific antibodies to basement membrane components may help to differentiate ameloblastomas from malignant lesions.
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PMID:Basement membrane confinement of epithelial tumor islands in benign and malignant ameloblastomas. 392 73

The present report of a malignant metastasizing ameloblastoma and a critical review of literature was undertaken in an attempt to better understand the biological potential and behavior of this rare tumor and thus to facilitate its clinical management. Most of the 26 patients with a proven malignant ameloblastoma including the present case had developed multiple recurrences. The lung was the most frequent metastatic site (88%) followed by regional lymph nodes (27%). Furthermore metastases were observed in some cases in the bone, brain, kidney, small intestine and liver. The interval between diagnosis of tumor and manifestation of metastases was long with a median of 11.1 years. The average survival time was 13.1 years. By contrast, the interval between diagnosis of metastatic disease and death was relatively short (median: 2.6 years). The histologic and cytologic pattern of malignant ameloblastoma and of its metastases was not significantly different from that of non-metastatic ameloblastoma. Because of the lack of morphological criteria of malignancy the biological behavior of ameloblastomas cannot be predicted. It is difficult to be certain which factors are important in the delayed induction of metastases. It is suspected that ameloblastomas possess an inherent low grade malignancy which is stimulated by multiple recurrences. It is further assumed that the metastatic tumor cells have a slow growth rate resulting in late clinical manifestation of metastases. When lung metastases occur we recommend their surgical removal in order to prolong live expectancy or even to obtain a curative effect.
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PMID:Biology of metastasizing ameloblastoma. 408 Jun 38

Ameloblastoma is a locally invasive, histologically nonmalignant tumor that may on very rare occasions give rise to metastases. A patient with a mandibular ameloblastoma presenting typical histologic appearances developed a pulmonary metastasis confirmed by histology as arising from the primary tumor. Two groups of these extremely rare malignant ameloblastomas can be distinguished: those without histologic signs of degeneration that give rise to metastases identical to the primary lesion, and those with degenerative signs provoking metastases with the histologic appearance of undifferentiated carcinoma. No relation appears to exist between size of primary tumor, histologic type of ameloblastoma, or its course and tendency to produce metastases.
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PMID:[Malignant ameloblastoma. Apropos of a case]. 657 36

A case of metastatic ameloblastoma of the maxilla with secondary hypercalcemia in a 54-year-old man is presented. After treatment with surgery, chemotherapy, and radiotherapy, the patient was found to have multiple metastases and severe hypercalcemia associated with high levels of parathormone-like substance in the peripheral blood. At autopsy he was found to have widespread metastases and nephrocalcinosis.
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PMID:Ameloblastoma of the maxilla with distant metastases and hypercalcemia. 722 20

Adamantinoma of long bones is a rare malignant tumor composed of cells with epithelial characteristics in various differentiation patterns surrounded by fibrous cells. Evidence as to whether this neoplasm should be designated as an epithelial bone tumor or a biphasic sarcoma with both epithelial and mesenchymal features is lacking. In this study the nature of the mesenchymal and epithelial components of adamantinoma was investigated by DNA flow cytometry, DNA image cytometry, p53 immunohistochemistry, and polymerase chain reaction-based loss of heterozygosity detection at the p53 locus. Specimens from 6 of 15 patients (40%) analyzed by flow cytometry had an aneuploid DNA index. Image cytometry analysis of Feulgen-stained paraffin sections of 6 aneuploid and 2 diploid tumors revealed that aneuploid nuclei were detected in cells with an epithelial phenotype only, whereas all fibrous cells were diploid. Immunohistochemistry for p53 on specimens from 25 patients revealed moderate or strong immunoreactivity in 12 tumors (48%) restricted to the epithelial cells. Loss of heterozygosity at the p53 locus could be confirmed in the epithelial component of an immunohistochemically p53-positive tumor. Additionally, sections of 7 lung metastases were studied histologically. Only keratin-positive epithelial cells, predominantly in the spindle cell pattern, were present in these metastases, whereas the osteofibrous tissue present in the primary tumors was not detected. These results suggest that either adamantinoma consists of a malignant epithelial part with a reactive osteofibrous stroma or that the malignant epithelial cells develop next to a proliferating benign fibrous component. Additional analysis of common genetic abnormalities in the fibrous and epithelial cells of adamantinoma is therefore indicated.
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PMID:DNA aberrations in the epithelial cell component of adamantinoma of long bones. 749 1

Ameloblastic carcinoma is an unusual tumour. There have been a total of 34 cases of ameloblastic carcinoma in the English literature to date. Of these only 11 cases have occurred in the maxilla. The authors report the 12th such case. The histological classification for odontogenic carcinoma has been debated for many years and recently revised, thus differentiating between malignant ameloblastoma and ameloblastic carcinoma. The authors review the current literature regarding diagnosis and treatment of this unusual lesion, and support the use of the term malignant ameloblastoma for the tumours that metastasize in spite of their benign histological appearance, whereas, the ameloblastic carcinoma is referred to as the primary tumour with malignant transformation, regardless of its metastatic potential.
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PMID:Ameloblastic carcinoma of the maxilla. 749 39

This article describes the acanthomatous epulis in dogs, a quite common lesion that appears to be the counterpart of human ameloblastoma. Histologically, it resembles closely the acanthomatous pattern of human ameloblastoma and, like ameloblastomas in human beings, it infiltrates cancellous bone; moreover, it has no tendency to metastasize. Veterinarians have sometimes treated the acanthomatous epulis with therapeutic irradiation, providing one example when this tumor served as an animal model for human ameloblastoma. Although this treatment has cured some animals, others have developed postirradiation malignancies.
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PMID:Canine acanthomatous epulis. The only common spontaneous ameloblastoma in animals. 760 Feb 26

Adamantinomas are slow-growing, invasive malignant tumors. Although the majority of cases have arisen in the tibia, these aggressive tumors have been reported in most of the long bones. This is the first known report of a patient with adamantinoma of the olecranon, an unusual site for this lesion. However, the patient not only had a novel site of appearance of the tumor and local recurrence of the disease, but also had a series of distant, isolated, bony tissue metastases before a fatal metastasis to the lung within a 9-year period. Although metastasis to other bony sites has been reported, a series of metastases to bony and soft tissues is unusual.
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PMID:Adamantinoma of the olecranon. A report of a case with serial metastasizing lesions. 764 38

A case of a malignant ameloblastoma in a 49-year old Sri Lankan woman with widespread pulmonary metastases is presented, the diagnosis confirmed by needle biopsy. The current histological classification of odontogenic carcinomas and the management of metastatic pulmonary deposits are discussed.
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PMID:Malignant ameloblastoma revisited. 771 30


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