Ossifying Fibroma of Non-odontogenic Origin: A Fibro-osseous Lesion in the Craniofacial Skeleton to be (Re-)considered

In the cranio-facial skeleton, a heterogeneous group of well characterized fibro-osseous lesions can be distinguished. Whereas fibrous dysplasia can affect any skeletal bone, ossifying fibroma and cemento-osseous dysplasia exclusively develop in the cranio-facial region, with most subtypes restricted to the tooth bearing areas of the jaws. Herein we present a series of 20 fibro-osseous lesions that developed mostly in the frontal bone and in the mandible, presenting as expansile intramedullary tumors with a unique histologic appearance and an indolent clinical course. We provide evidence that these tumors are distinct from the categories included in the WHO classification and are therefore currently unclassifiable. The definition of cemento-ossifying fibroma as an odontogenic neoplasm developing only in close proximity to teeth should be re-considered and incorporate also extragnathic lesions as shown here

Oral acantholytic squamous cell carcinoma shares clinical and histological features with angiosarcoma

<p>Abstract</p> <p>Background</p> <p>acantholytic squamous cell carcinomas (ASCC) and intraoral angiosarcoma share similar histopathological features. Aim of this study was to find marker for a clear distinction.</p> <p>Methods</p> <p>Four oral acantholytic squamous cell carcinomas and one intraoral angiosarcoma are used to compare the eruptive intraoral growth-pattern, age-peak, unfavourable prognosis and slit-like intratumorous spaces in common histological staining as identical clinical and histopathological features. Immunohistochemical staining for pancytokeratin, cytokeratin, collagen type IV, γ2-chain of laminin-5, endothelial differentiation marker CD31 and CD34, F VIII-associated antigen, Ki 67-antigen, β-catenin, E-cadherin, α-smooth-muscle-actin and Fli-1 were done.</p> <p>Results</p> <p>Cytokeratin-immunoreactive cells can be identified in both lesions. The large vascularization of ASCC complicates the interpretation of vascular differential markers being characteristic for angiosarcoma. Loss of cell-cell-adhesion, monitored by loss of E-cadherin and β-catenin membrane-staining, are indetified as reasons for massive expression of invasion-factor ln-5 in ASCC and considered responsible for unfavourable prognosis of ASCC. Expression of Fli-1 in angiosarcoma and cellular immunoreaction for ln-5 in ASCC are worked out as distinguishing features of both entities.</p> <p>Conclusion</p> <p>Fli-1 in angiosarcoma and ln-5 in ASCC are distinguishing features.</p

Primary Extracranial Meningiomas: An Analysis of 146 Cases

Primary extracranial meningiomas are rare neoplasms, frequently misdiagnosed, resulting in inappropriate clinical management. To date, a large clinicopathologic study has not been reported. One hundred and forty-six cases diagnosed between 1970 and 1999 were retrieved from the files of the Armed Forces Institute of Pathology. Histologic features were reviewed, immunohistochemistry analysis was performed (n = 85), and patient follow-up was obtained (n = 110). The patients included 74 (50.7%) females and 72 (49.3%) males. Tumors of the skin were much more common in males than females (1.7:1). There was an overall mean age at presentation of 42.4 years, with a range of 0.3–88 years. The overall mean age at presentation was significantly younger for skin primaries (36.2 years) than for ear (50.1 years) and nasal cavity (47.1 years) primaries. Symptoms were in general non-specific and reflected the anatomic site of involvement, affecting the following areas in order of frequency: scalp skin (40.4%), ear and temporal bone (26%), and sinonasal tract (24%). The tumors ranged in size from 0.5 up to 8 cm, with a mean size of 2.3 cm. Histologically, the majority of tumors were meningothelial (77.4%), followed by atypical (7.5%), psammomatous (4.1%) and anaplastic (2.7%). Psammoma bodies were present in 45 tumors (30.8%), and bone invasion in 31 (21.2%) of tumors. The vast majority were WHO Grade I tumors (87.7%), followed by Grade II (9.6%) and Grade III (2.7%) tumors. Immunohistochemically, the tumor cells labeled for EMA (76%; 61/80), S-100 protein (19%; 15/78), CK 7 (22%; 12/55), and while there was ki-67 labeling in 27% (21/78), <3% of cells were positive. The differential diagnosis included a number of mesenchymal and epithelial tumors (paraganglioma, schwannoma, carcinoma, melanoma, neuroendocrine adenoma of the middle ear), depending on the anatomic site of involvement. Treatment and follow-up was available in 110 patients: Biopsy, local excision, or wide excision was employed. Follow-up time ranged from 1 month to 32 years, with an average of 14.5 years. Recurrences were noted in 26 (23.6%) patients, who were further managed by additional surgery. At last follow-up, recurrent disease was persistent in 15 patients (mean, 7.7 years): 13 patients were dead (died with disease) and two were alive; the remaining patients were disease free (alive 60, mean 19.0 years, dead 35, mean 9.6 years). There is no statistically significant difference in 5-year survival rates by site: ear and temporal bone: 83.3%; nasal cavity: 81.8%; scalp skin: 78.5%; other sites: 65.5% (P = 0.155). Meningiomas can present in a wide variety of sites, especially within the head and neck region. They behave as slow-growing neoplasms with a good prognosis, with longest survival associated with younger age, and complete resection. Awareness of this diagnosis in an unexpected location will help to avoid potential difficulties associated with the diagnosis and management of these tumors