Oral perineurioma: clinicopathologic features from two cases and review of literature.

The present study reports two cases of oral perineuriomas, including a clinicopathologic review of the 39 published cases (17 intraneural and 22 extraneural perineuriomas) in the English language literature. In the first case, the tumor occurred in an 84-year-old male as a painless, asymptomatic, 20-mm submucosal nodule on the right lower mucobuccal fold near to the premolar area. In the second case, a 46-year-old female presented with a painless, 25-mm, slow-growing, fibrous, pedunculated nodule on the right buccal mucosa. In the first case, the tumor was composed of spindle cells arranged in a storiform pattern, classified as intraneural perineurioma; and in the second, it was an extraneural perineurioma, showing a whorled myxoid stroma. Immunohistochemical analysis confirmed the diagnosis by showing positivity for vimentin, EMA, and Glut-1 in case 1 and EMA, Glut-1, Claudin-1, and CD34 (focally) in case 2. Complete surgical removal was performed for both tumors, and there was no evidence of local recurrence after a long-term follow-up.

Clinicopathologic analysis and syndecan-1 and Ki-67 expression in calcifying cystic odontogenic tumors, dentinogenic ghost cell tumor, and ghost cell odontogenic carcinoma.

OBJECTIVE: Benign and malignant tumor cells can express altered adhesion properties, and these features can be associated with their proliferative and invasive characteristics. This study aimed to evaluate syndecan-1 and Ki-67 expression in ghost cell-containing odontogenic tumors. STUDY DESIGN: Clinical data were retrieved from laboratory records, and hematoxylin-eosin-stained slides and sections, labeled with monoclonal antibodies anti-syndecan-1 and anti-Ki-67 using the immunoperoxidase technique, were evaluated. RESULTS: Included were 21 central calcifying cystic odontogenic tumors (CCOTs) (4 associated with odontoma), 2 peripheral CCOTs, 1 dentinogenic ghost cell tumor, and 1 ghost cell odontogenic carcinoma (GCOC). Syndecan-1 was mainly expressed in cells resembling stellate reticulum and in stromal cells from the fibrous capsule. The mean Ki-67 labeling index was 4.1% (49.3% for GCOC), but it was not associated with syndecan-1 expression. CONCLUSIONS: Syndecan-1 is variably expressed in cells resembling the stellate reticulum, stromal cells, and basal cells and might be associated with the biology of these tumors.